Sample records for eocene primate teilhardina

  1. New fossils of the oldest North American euprimate Teilhardina brandti (Omomyidae) from the paleocene-eocene thermal maximum. (United States)

    Rose, Kenneth D; Chester, Stephen G B; Dunn, Rachel H; Boyer, Doug M; Bloch, Jonathan I


    More than 25 new specimens of Teilhardina brandti, one of the oldest known euprimates, are reported from earliest Eocene strata of the southern Bighorn Basin, Wyoming. The new fossils include the first upper dentitions, a dentary showing the lower dental formula for the first time, and the first postcrania ascribed to T. brandti (tarsals and terminal phalanges). The elongated navicular and long talar neck suggest that T. brandti was an active arboreal quadruped, and the terminal phalanges constitute the oldest evidence for nails in Euprimates. Phylogenetic analysis incorporating the new data indicates that T. brandti is more derived than T. belgica but less so than T. americana. The hypothesis that Teilhardina originated in Asia (T. asiatica) and dispersed westward to Europe (T. belgica) and then to North America (T. brandti and T. magnoliana) during the earliest Eocene Paleocene-Eocene Thermal Maximum is most consistent with available evidence, including the relative age of fossil samples and their stage of evolution. Copyright © 2011 Wiley-Liss, Inc.

  2. Recent advances on the knowledge of the Eocene primates from the Pyrenean Basins (NE Spain) (United States)

    Minwer-Barakat, Raef; Marigó, Judit; Femenias-Gual, Joan; Moyà-Solà, Salvador


    The Eocene was one of the warmest epochs of the Cenozoic and documented the first occurrence of several orders of modern mammals. Among them, Euprimates underwent a very important radiation favored by the development of dense forests throughout the Northern Hemisphere. Two main groups reached a great abundance and diversity during the Eocene, Adapiformes and Omomyiformes, which are related to the main clades of living primates (strepsirrhines and haplorhines, respectively). In the Iberian Peninsula, Eocene primates have been known since the 1960s, when several fossil sites containing prosimian remains were discovered. Nevertheless, it was not until 2010 that the research on Eocene primates from Spain has increased strikingly, and the results achieved in this last stage have surpassed those of the whole past century in terms of number of publications. Besides some interesting findings in the Ebro, Almazán and Miranda-Trebiño basins, the Pyrenees have yielded the most abundant record of Eocene primates from the Iberian Peninsula, constituting therefore an excellent region for evaluating the evolution of primates through this epoch. In the early Eocene continental deposits of the Àger area, adapiforms are well represented, with three species of the genus Agerinia. Besides, the only record of Plesiadapiformes (archaic primates) from Spain has been documented in this zone. The middle Eocene is particularly well represented in the Eastern Pyrenees. In the section of Sant Jaume de Frontanyà, three primate species have been described in the last years. The adapiform Anchomomys frontanyensis and the omomyiform Pseudoloris pyrenaicus, found in the oldest levels of the section, and the omomyiform Necrolemur anadoni, identified in the youngest levels, have allowed reconstructing the relationships of these taxa with their correlatives found in other parts of Europe. Late Eocene deposits with mammal remains crop out in the area of La Pobla de Segur. The most relevant fossil

  3. A new primate assemblage from La Verrerie de Roches (Middle Eocene, Switzerland). (United States)

    Minwer-Barakat, Raef; Marigó, Judit; Becker, Damien; Costeur, Loïc


    Primates reached a great abundance and diversity during the Eocene, favored by warm temperatures and by the development of dense forests throughout the Northern Hemisphere. Here we describe new primate material from La Verrerie de Roches, a Middle Eocene karstic infill situated in the Jura Region (Switzerland), consisting of more than 80 dental remains. The primate assemblage from La Verrerie de Roches includes five different taxa. The best represented primate is Necrolemur aff. anadoni, similar in size and overall morphology to Necrolemur anadoni but resembling in some features the younger species Necrolemur antiquus. Microchoerines are also represented by two species of Pseudoloris, P. pyrenaicus and Pseudoloris parvulus, constituting the unique joint record of these two species known up to now. Remains of Adapiformes are limited to one isolated tooth of a large anchomomyin and another tooth belonging to the small adapine Microadapis cf. sciureus. The studied primate association allows assigning La Verrerie de Roches to the Robiacian Land Mammal Age. More specifically, this site can be confidently situated between the MP15 and MP16 reference levels, although the primate assemblage probably indicates some degree of temporal mixing. This is the first record of P. pyrenaicus and a form closely related to N. anadoni out of the Iberian Peninsula. The identification of these microchoerines in Switzerland gives further support to the connection of NE Spain and Central Europe during the Middle Eocene. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Eocene primates of South America and the African origins of New World monkeys (United States)

    Bond, Mariano; Tejedor, Marcelo F.; Campbell, Kenneth E.; Chornogubsky, Laura; Novo, Nelson; Goin, Francisco


    The platyrrhine primates, or New World monkeys, are immigrant mammals whose fossil record comes from Tertiary and Quaternary sediments of South America and the Caribbean Greater Antilles. The time and place of platyrrhine origins are some of the most controversial issues in primate palaeontology, although an African Palaeogene ancestry has been presumed by most primatologists. Until now, the oldest fossil records of New World monkeys have come from Salla, Bolivia, and date to approximately 26 million years ago, or the Late Oligocene epoch. Here we report the discovery of new primates from the ?Late Eocene epoch of Amazonian Peru, which extends the fossil record of primates in South America back approximately 10 million years. The new specimens are important for understanding the origin and early evolution of modern platyrrhine primates because they bear little resemblance to any extinct or living South American primate, but they do bear striking resemblances to Eocene African anthropoids, and our phylogenetic analysis suggests a relationship with African taxa. The discovery of these new primates brings the first appearance datum of caviomorph rodents and primates in South America back into close correspondence, but raises new questions about the timing and means of arrival of these two mammalian groups.

  5. Djebelemur, a tiny pre-tooth-combed primate from the Eocene of Tunisia: a glimpse into the origin of crown strepsirhines.

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    Laurent Marivaux

    Full Text Available BACKGROUND: Molecular clock estimates of crown strepsirhine origins generally advocate an ancient antiquity for Malagasy lemuriforms and Afro-Asian lorisiforms, near the onset of the Tertiary but most often extending back to the Late Cretaceous. Despite their inferred early origin, the subsequent evolutionary histories of both groups (except for the Malagasy aye-aye lineage exhibit a vacuum of lineage diversification during most part of the Eocene, followed by a relative acceleration in diversification from the late Middle Eocene. This early evolutionary stasis was tentatively explained by the possibility of unrecorded lineage extinctions during the early Tertiary. However, this prevailing molecular view regarding the ancient origin and early diversification of crown strepsirhines must be viewed with skepticism due to the new but still scarce paleontological evidence gathered in recent years. METHODOLOGICAL/PRINCIPAL FINDINGS: Here, we describe new fossils attributable to Djebelemur martinezi, a≈50 Ma primate from Tunisia (Djebel Chambi. This taxon was originally interpreted as a cercamoniine adapiform based on limited information from its lower dentition. The new fossils provide anatomical evidence demonstrating that Djebelemur was not an adapiform but clearly a distant relative of lemurs, lorises and galagos. Cranial, dental and postcranial remains indicate that this diminutive primate was likely nocturnal, predatory (primarily insectivorous, and engaged in a form of generalized arboreal quadrupedalism with frequent horizontal leaping. Djebelemur did not have an anterior lower dentition as specialized as that characterizing most crown strepsirhines (i.e., tooth-comb, but it clearly exhibited a transformed antemolar pattern representing an early stage of a crown strepsirhine-like adaptation ("pre-tooth-comb". CONCLUSIONS/SIGNIFICANCE: These new fossil data suggest that the differentiation of the tooth-comb must postdate the djebelemurid

  6. Hands of early primates. (United States)

    Boyer, Doug M; Yapuncich, Gabriel S; Chester, Stephen G B; Bloch, Jonathan I; Godinot, Marc


    Questions surrounding the origin and early evolution of primates continue to be the subject of debate. Though anatomy of the skull and inferred dietary shifts are often the focus, detailed studies of postcrania and inferred locomotor capabilities can also provide crucial data that advance understanding of transitions in early primate evolution. In particular, the hand skeleton includes characteristics thought to reflect foraging, locomotion, and posture. Here we review what is known about the early evolution of primate hands from a comparative perspective that incorporates data from the fossil record. Additionally, we provide new comparative data and documentation of skeletal morphology for Paleogene plesiadapiforms, notharctines, cercamoniines, adapines, and omomyiforms. Finally, we discuss implications of these data for understanding locomotor transitions during the origin and early evolutionary history of primates. Known plesiadapiform species cannot be differentiated from extant primates based on either intrinsic hand proportions or hand-to-body size proportions. Nonetheless, the presence of claws and a different metacarpophalangeal [corrected] joint form in plesiadapiforms indicate different grasping mechanics. Notharctines and cercamoniines have intrinsic hand proportions with extremely elongated proximal phalanges and digit rays relative to metacarpals, resembling tarsiers and galagos. But their hand-to-body size proportions are typical of many extant primates (unlike those of tarsiers, and possibly Teilhardina, which have extremely large hands). Non-adapine adapiforms and omomyids exhibit additional carpal features suggesting more limited dorsiflexion, greater ulnar deviation, and a more habitually divergent pollex than observed plesiadapiforms. Together, features differentiating adapiforms and omomyiforms from plesiadapiforms indicate increased reliance on vertical prehensile-clinging and grasp-leaping, possibly in combination with predatory behaviors in

  7. Middle Eocene rodents from Peruvian Amazonia reveal the pattern and timing of caviomorph origins and biogeography (United States)

    Antoine, Pierre-Olivier; Marivaux, Laurent; Croft, Darin A.; Billet, Guillaume; Ganerød, Morgan; Jaramillo, Carlos; Martin, Thomas; Orliac, Maëva J.; Tejada, Julia; Altamirano, Ali J.; Duranthon, Francis; Fanjat, Grégory; Rousse, Sonia; Gismondi, Rodolfo Salas


    The long-term isolation of South America during most of the Cenozoic produced a highly peculiar terrestrial vertebrate biota, with a wide array of mammal groups, among which caviomorph rodents and platyrrhine primates are Mid-Cenozoic immigrants. In the absence of indisputable pre-Oligocene South American rodents or primates, the mode, timing and biogeography of these extraordinary dispersals remained debated. Here, we describe South America's oldest known rodents, based on a new diverse caviomorph assemblage from the late Middle Eocene (approx. 41 Ma) of Peru, including five small rodents with three stem caviomorphs. Instead of being tied to the Eocene/Oligocene global cooling and drying episode (approx. 34 Ma), as previously considered, the arrival of caviomorphs and their initial radiation in South America probably occurred under much warmer and wetter conditions, around the Mid-Eocene Climatic Optimum. Our phylogenetic results reaffirm the African origin of South American rodents and support a trans-Atlantic dispersal of these mammals during Middle Eocene times. This discovery further extends the gap (approx. 15 Myr) between first appearances of rodents and primates in South America. PMID:21993503

  8. Seasonal variability in Arctic temperatures during the early Eocene (United States)

    Eberle, J. J.; Fricke, H. C.; Humphrey, J.; Hackett, L.; Newbrey, M.; Hutchison, H.


    As a deep time analog for today’s rapidly warming Arctic region, early Eocene (~53 Ma) rocks on Ellesmere Island, Arctic Canada (~79° N.) preserve evidence of lush swamp forests inhabited by turtles, alligators, primates, tapirs, and hippo-like Coryphodon. Although the rich flora and fauna of the early Eocene Arctic imply warmer, wetter conditions that at present, quantitative estimates of Eocene Arctic climate are rare. By analyzing oxygen isotope ratios of biogenic phosphate from mammal, fish, and turtle fossils from a single locality on central Ellesmere Island, we provide estimates of early Eocene Arctic temperature, including mean annual temperature (MAT) of ~ 8° C, mean annual range in temperature (MART) of ~ 16.5° C, warm month mean temperature (WMMT) of 16 - 19° C, and cold month mean temperature (CMMT) of 0 - 1° C. Our seasonal range in temperature is similar to the range in estimated MAT obtained using different proxies. In particular, unusually high estimates of early Eocene Arctic MAT and sea surface temperature (SST) by others that are based upon the distribution of branched glycerol dialkyl glycerol tetraether (GDGT) membrane lipids in terrestrial soil bacteria and marine Crenarchaeota fall within our range of WMMT, suggesting a bias towards summer values. Consequently, caution should be taken when using these methods to infer MAT and SST that, in turn, are used to constrain climate models. From a paleontologic perspective, our temperature estimates verify that alligators and tortoises, by way of nearest living relative-based climatic inference, are viable paleoclimate proxies for mild, above-freezing year-round temperatures. Although in both of these reptiles, past temperature tolerances were greater than in their living descendants.

  9. First middle Miocene sivaladapid primate from Thailand

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    Chaimanee, Y.; Yamee, C.; Tian, P.; Chavasseau, O.; Jaeger, J.J. [Bureau for Paleontology & Museum, Bangkok (Thailand). Dept. for Mineral Resources


    Sivaladapids are a group of Asian adapiform primates that were previously documented from deposits dating to the middle Eocene through the late Miocene in Pakistan, India, Myanmar, Thailand, and China. The group is notable for the persistence of three genera, Sivaladapis, Indraloris and Sinoadapis, into the late Miocene. In Thailand, sivaladapids were previously documented only from late Eocene deposits of the Krabi mine. Here, we describe the first Southeast Asian Miocene sivaladapid, Siamoadapis maemohensis gen. et sp. nov. from a 13.3 to 13.1 Ma lignite layer from the Mae Moh coal mine, Thailand. It differs from other Miocene sivaladapids by its distinctly smaller size and in features of the dentition. This discovery enhances the paleoecological diversity of the middle Miocene primate fauna of Thailand, which now includes sivaladapids, a loris, tarsiids, and hominoids. In this respect, the fossil primate community from the middle Miocene of Thailand is similar in its composition to roughly contemporaneous assemblages from southern China, India, and Pakistan. However, the Thai fossils represent a distinct genus, suggesting a different biogeographic province with distinctive paleoenvironments.

  10. Phalangeal morphology of Shanghuang fossil primates. (United States)

    Gebo, Daniel L; Dagosto, Marian; Ni, Xijun; Beard, K Christopher


    Here, we describe hundreds of isolated phalanges attributed to middle Eocene fossil primates from the Shanghuang fissure-fillings from southern Jiangsu Province, China. Extending knowledge based on previous descriptions of postcranial material from Shanghuang, this sample of primate finger and toe bones includes proximal phalanges, middle phalanges, and over three hundred nail-bearing distal phalanges. Most of the isolated proximal and middle phalanges fall within the range of small-bodied individuals, suggesting an allocation to the smaller haplorhine primates identified at Shanghuang, including eosimiids. In contrast to the proximal and middle phalanges from Shanghuang, there are a variety of shapes, sizes, and possible taxonomic allocations for the distal phalanges. Two distal phalangeal morphologies are numerically predominant at Shanghuang. The sample of larger bodied specimens is best allocated to the medium-sized adapiform Adapoides while the smaller ones are allocated to eosimiids on the basis of the commonality of dental and tarsal remains of these taxa at Shanghuang. The digit morphology of Adapoides is similar morphologically to that of notharctines and cercamoniines, while eosimiid digit morphology is unlike living anthropoids. Other primate distal phalangeal morphologies at Shanghuang include grooming "claws" as well as specimens attributable to tarsiids, tarsiiforms, the genus Macrotarsius, and a variety of adapiforms. One group of distal phalanges at Shanghuang is morphologically indistinguishable from those of living anthropoids. All of the phalanges suggest long fingers and toes for the fossil primates of Shanghaung, and their digit morphology implies arboreality with well-developed digital flexion and strong, grasping hands and feet. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Property in Nonhuman Primates (United States)

    Brosnan, Sarah F.


    Property is rare in most nonhuman primates, most likely because their lifestyles are not conducive to it. Nonetheless, just because these species do not frequently maintain property does not mean that they lack the propensity to do so. Primates show respect for possession, as well as behaviors related to property, such as irrational decision…

  12. Raptors and primate evolution. (United States)

    McGraw, W Scott; Berger, Lee R


    Most scholars agree that avoiding predators is a central concern of lemurs, monkeys, and apes. However, given uncertainties about the frequency with which primates actually become prey, the selective importance of predation in primate evolution continues to be debated. Some argue that primates are often killed by predators, while others maintain that such events are relatively rare. Some authors have contended that predation's influence on primate sociality has been trivial; others counter that predation need not occur often to be a powerful selective force. Given the challenges of documenting events that can be ephemeral and irregular, we are unlikely ever to amass the volume of systematic, comparative data we have on such topics as feeding, social dynamics, or locomotor behavior. Nevertheless, a steady accumulation of field observations, insight gained from natural experiments, and novel taphonomic analyses have enhanced understanding of how primates interact with several predators, especially raptors, the subject of this review. Copyright © 2013 Wiley Periodicals, Inc.

  13. Eocene squalomorph sharks (Chondrichthyes, Elasmobranchii) from Antarctica (United States)

    Engelbrecht, Andrea; Mörs, Thomas; Reguero, Marcelo A.; Kriwet, Jürgen


    Rare remains of predominantly deep-water sharks of the families Hexanchidae, Squalidae, Dalatiidae, Centrophoridae, and Squatinidae are described from the Eocene La Meseta Formation, Seymour Island, Antarctic Peninsula, which has yielded the most abundant chondrichthyan assemblage from the Southern Hemisphere to date. Previously described representatives of Hexanchus sp., Squalus weltoni, Squalus woodburnei, Centrophorus sp., and Squatina sp. are confirmed and dental variations are documented. Although the teeth of Squatina sp. differ from other Palaeogene squatinid species, we refrain from introducing a new species. A new dalatiid taxon, Eodalatias austrinalis gen. et sp. nov. is described. This new material not only increases the diversity of Eocene Antarctic elasmobranchs but also allows assuming that favourable deep-water habitats were available in the Eocene Antarctic Ocean off Antarctica in the Eocene. The occurrences of deep-water inhabitants in shallow, near-coastal waters of the Antarctic Peninsula agrees well with extant distribution patterns.

  14. Understanding primate brain evolution


    Dunbar, R.I.M; Shultz, Susanne


    We present a detailed reanalysis of the comparative brain data for primates, and develop a model using path analysis that seeks to present the coevolution of primate brain (neocortex) and sociality within a broader ecological and life-history framework. We show that body size, basal metabolic rate and life history act as constraints on brain evolution and through this influence the coevolution of neocortex size and group size. However, they do not determine either of these variables, which ap...

  15. Macroevolutionary dynamics and historical biogeography of primate diversification inferred from a species supermatrix.

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    Mark S Springer

    Full Text Available Phylogenetic relationships, divergence times, and patterns of biogeographic descent among primate species are both complex and contentious. Here, we generate a robust molecular phylogeny for 70 primate genera and 367 primate species based on a concatenation of 69 nuclear gene segments and ten mitochondrial gene sequences, most of which were extracted from GenBank. Relaxed clock analyses of divergence times with 14 fossil-calibrated nodes suggest that living Primates last shared a common ancestor 71-63 Ma, and that divergences within both Strepsirrhini and Haplorhini are entirely post-Cretaceous. These results are consistent with the hypothesis that the Cretaceous-Paleogene mass extinction of non-avian dinosaurs played an important role in the diversification of placental mammals. Previous queries into primate historical biogeography have suggested Africa, Asia, Europe, or North America as the ancestral area of crown primates, but were based on methods that were coopted from phylogeny reconstruction. By contrast, we analyzed our molecular phylogeny with two methods that were developed explicitly for ancestral area reconstruction, and find support for the hypothesis that the most recent common ancestor of living Primates resided in Asia. Analyses of primate macroevolutionary dynamics provide support for a diversification rate increase in the late Miocene, possibly in response to elevated global mean temperatures, and are consistent with the fossil record. By contrast, diversification analyses failed to detect evidence for rate-shift changes near the Eocene-Oligocene boundary even though the fossil record provides clear evidence for a major turnover event ("Grande Coupure" at this time. Our results highlight the power and limitations of inferring diversification dynamics from molecular phylogenies, as well as the sensitivity of diversification analyses to different species concepts.

  16. Strong Equatorial Seasonality during Early Eocene greenhouse (United States)

    Samanta, Arpita; Sarkar, Anindya


    A warm greenhouse climate, punctuated by a series of rapid warming events (known as hyperthermals), is characteristic of the Late Paleocene to Early Eocene period. Rapid addition of 13C depleted carbon to the exogenic carbon cycle, in an otherwise overall higher atmospheric CO2 level, is thought to set off the hyperthermal events. For understanding the fate of ongoing global warming and response of the climate system and biota, researchers for past few decades are paying more attention to comprehend this climatic enigma. Existing proxies from the most distinct hyperthermal event i.e., PETM indicate that the mean annual sea surface temperature (MASST) was comparatively higher (by ˜8 ˚ C) at high latitude and to a lesser extent towards the equator. Apart from the prominent hyperthermal events the rest of the Early Eocene was significantly warmer and thought to be more equable compare to present. Terrestrial proxy records from the mid-latitude regions indicated that the Mean Annual Temperature (MAT) and Minimum Winter Temperature (MWT) was high, thus reducing the seasonality or difference between MWT and Maximum Summer Temperature (MST). In absence of proxy data from the low latitude region, a ≥40 ˚ C summer temperature was predicted assuming a mild Eocene temperature gradient of ˜0.4 ˚ C/ ˚ latitude and mid-latitude temperature data. Even question was raised about the existence of the tropical rain forest in such climatic extreme. Recent pollen census data, on contrary, suggest proliferation of the tropical rain forest during this climatic extreme. Important in this context is that there is a very few direct evidence of Late Paleocene-Early Eocene MAT and seasonality data from the low latitude/equatorial regions. To resolve this issue, oxygen and carbon isotope ratios of larger benthic foraminifera (Nummulites burdigalensis) were measured in laser based carbonate device attached with the Delta V advantage continuous flow stable isotope ratio mass spectrometer

  17. Early Eocene rodents (Mammalia) from the Subathu Formation of ...

    Indian Academy of Sciences (India)

    Permanent link: Keywords. Mammalia; Rodentia; Chapattimyidae; Eocene; Subathu Formation; India. Abstract. Based on isolated upper cheek teeth, two new early Eocene rodents (Subathumys solanorius gen. et sp. nov. and Subathumys globulus gen. et sp. nov.) ...

  18. Early Eocene birds from La Borie, southern France

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    Bourdon, Estelle; Mourer-Chauviré, Cécile; Laurent, Yves


    The Early Eocene locality of La Borie is located in the village of Saint-Papoul, in southern France. These Eocene fluvio-lacustrine clay deposits have yielded numerous vertebrate remains. Mammalian taxa found in the fossiliferous levels indicate an age near the reference level MP 8–9, which...

  19. Evidence for a grooming claw in a North American adapiform primate: implications for anthropoid origins.

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    Stephanie Maiolino

    Full Text Available Among fossil primates, the Eocene adapiforms have been suggested as the closest relatives of living anthropoids (monkeys, apes, and humans. Central to this argument is the form of the second pedal digit. Extant strepsirrhines and tarsiers possess a grooming claw on this digit, while most anthropoids have a nail. While controversial, the possible presence of a nail in certain European adapiforms has been considered evidence for anthropoid affinities. Skeletons preserved well enough to test this idea have been lacking for North American adapiforms. Here, we document and quantitatively analyze, for the first time, a dentally associated skeleton of Notharctus tenebrosus from the early Eocene of Wyoming that preserves the complete bones of digit II in semi-articulation. Utilizing twelve shape variables, we compare the distal phalanges of Notharctus tenebrosus to those of extant primates that bear nails (n = 21, tegulae (n = 4, and grooming claws (n = 10, and those of non-primates that bear claws (n = 7. Quantitative analyses demonstrate that Notharctus tenebrosus possessed a grooming claw with a surprisingly well-developed apical tuft on its second pedal digit. The presence of a wide apical tuft on the pedal digit II of Notharctus tenebrosus may reflect intermediate morphology between a typical grooming claw and a nail, which is consistent with the recent hypothesis that loss of a grooming claw occurred in a clade containing adapiforms (e.g. Darwinius masillae and anthropoids. However, a cladistic analysis including newly documented morphologies and thorough representation of characters acknowledged to have states constituting strepsirrhine, haplorhine, and anthropoid synapomorphies groups Notharctus tenebrosus and Darwinius masillae with extant strepsirrhines rather than haplorhines suggesting that the form of pedal digit II reflects substantial homoplasy during the course of early primate evolution.

  20. Evidence for a grooming claw in a North American adapiform primate: implications for anthropoid origins. (United States)

    Maiolino, Stephanie; Boyer, Doug M; Bloch, Jonathan I; Gilbert, Christopher C; Groenke, Joseph


    Among fossil primates, the Eocene adapiforms have been suggested as the closest relatives of living anthropoids (monkeys, apes, and humans). Central to this argument is the form of the second pedal digit. Extant strepsirrhines and tarsiers possess a grooming claw on this digit, while most anthropoids have a nail. While controversial, the possible presence of a nail in certain European adapiforms has been considered evidence for anthropoid affinities. Skeletons preserved well enough to test this idea have been lacking for North American adapiforms. Here, we document and quantitatively analyze, for the first time, a dentally associated skeleton of Notharctus tenebrosus from the early Eocene of Wyoming that preserves the complete bones of digit II in semi-articulation. Utilizing twelve shape variables, we compare the distal phalanges of Notharctus tenebrosus to those of extant primates that bear nails (n = 21), tegulae (n = 4), and grooming claws (n = 10), and those of non-primates that bear claws (n = 7). Quantitative analyses demonstrate that Notharctus tenebrosus possessed a grooming claw with a surprisingly well-developed apical tuft on its second pedal digit. The presence of a wide apical tuft on the pedal digit II of Notharctus tenebrosus may reflect intermediate morphology between a typical grooming claw and a nail, which is consistent with the recent hypothesis that loss of a grooming claw occurred in a clade containing adapiforms (e.g. Darwinius masillae) and anthropoids. However, a cladistic analysis including newly documented morphologies and thorough representation of characters acknowledged to have states constituting strepsirrhine, haplorhine, and anthropoid synapomorphies groups Notharctus tenebrosus and Darwinius masillae with extant strepsirrhines rather than haplorhines suggesting that the form of pedal digit II reflects substantial homoplasy during the course of early primate evolution.

  1. Early Eocene birds from La Borie, southern France

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    Estelle Bourdon


    Full Text Available The early Eocene locality of La Borie is located in the village of Saint-Papoul, in southern France. These Eocene flu-vio-lacustrine clay deposits have yielded numerous vertebrate remains. Mammalian taxa found in the fossiliferous levels indicate an age near the reference level MP 8–9, which corresponds to the middle Ypresian, early Eocene. Here we provide a detailed description of the avian remains that were preliminarily reported in a recent study of the vertebrate fauna from La Borie. A maxilla, a quadrate, cervical vertebrae, a femur and two tibiotarsi are assigned to the giant ground bird Gastornis parisiensis (Gastornithidae. These new avian remains add to the fossil record of Gastornis, which is known from the late Paleocene to middle Eocene of Europe, early Eocene of Asia and early Eocene of North America. Gastornis parisiensis differs from the North American Gastornis giganteus in several features, including the more ventral position of the narial openings and the slender orbital process of quadrate. Two tibiotarsi and one tarsometatarsus are assigned to a new genus and species of Geranoididae, Galligeranoides boriensis gen. et sp. nov. So far, this family was known only from the early and middle Eocene of North America. The fossils from La Borie constitute the first record of the Geranoididae in Europe. We show that Gastornis coexisted with the Geranoididae in the early Eocene of both Europe (La Borie and North America (Willwood Formation. The presence of Geranoididae and the large flightless bird Gastornis on either side of the present-day North Atlantic provides further evidence that a high-latitude land connection existed between Europe and North America in the early Eocene.

  2. A new conservation strategy for China-A model starting with primates. (United States)

    Pan, Ruliang; Oxnard, Charles; Grueter, Cyril C; Li, Baoguo; Qi, Xiaoguang; He, Gang; Guo, Songtao; Garber, Paul A


    Although the evolutionary history of primates in China dates to the Eocene, and includes major radiations of lorisids, hominoids, cercopithecines, and colobines during the Miocene, Pliocene, and Pleistocene, extensive human-induced habitat change and deforestation over the past few centuries has resulted in 22 of 25 extant species listed as threatened or endangered, and two species of gibbons extirpated in the last few years. This commentary briefly reviews factors that have contributed to the decline of primates in China over the past 400 years, and in particular how major social events and economic development in modern China have resulted in unsustainable environmental change. In response, we describe our efforts to develop a strategic scientific, educational and conservation partnership in China, focusing on primates, in which GIS technology will be used to integrate geographical profiles, climatic information, and changes in land use patterns and human and nonhuman primate distributions to highlight issues of immediate concern and to develop priority-based conservation solutions. Our goal is to evaluate how human-induced environmental change has impacted primates over time and to predict the likelihood of primate population extinctions in the near future. This model represents an early warning system that will be widely available to the Chinese government, public, educational institutions, researchers, and NGOs through social media and educational videos in order to arouse public awareness and promote wildlife conservation. We encourage colleagues across a broad range of academic disciplines, political ideologies, and the public to help move this strategy into reality, the sooner the better. Am. J. Primatol. 78:1137-1148, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  3. Early Eocene deep-sea benthic foraminiferal faunas: Recovery from the Paleocene Eocene Thermal Maximum extinction in a greenhouse world (United States)

    Thomas, Ellen; D’haenens, Simon; Speijer, Robert P.; Alegret, Laia


    The early Eocene greenhouse world was marked by multiple transient hyperthermal events. The most extreme was the Paleocene-Eocene Thermal Maximum (PETM, ~56 Ma), linked to the extinction of the globally recognised deep-sea benthic foraminiferal Velasco fauna, which led to the development of early Eocene assemblages. This turnover has been studied at high resolution, but faunal development into the later early Eocene is poorly documented. There is no widely accepted early Eocene equivalent of the Late Cretaceous-Paleocene Velasco fauna, mainly due to the use of different taxonomic concepts. We compiled Ypresian benthic foraminiferal data from 17 middle bathyal-lower abyssal ocean drilling sites in the Pacific, Atlantic and Indian Oceans, in order to characterise early Eocene deep-sea faunas by comparing assemblages across space, paleodepth and time. Nuttallides truempyi, Oridorsalis umbonatus, Bulimina trinitatensis, the Bulimina simplex group, the Anomalinoides spissiformis group, pleurostomellids, uniserial lagenids, stilostomellids and lenticulinids were ubiquitous during the early Eocene (lower-middle Ypresian). Aragonia aragonensis, the Globocassidulina subglobosa group, the Cibicidoides eocaenus group and polymorphinids became ubiquitous during the middle Ypresian. The most abundant early Ypresian taxa were tolerant to stressed or disturbed environments, either by opportunistic behavior (Quadrimorphina profunda, Tappanina selmensis, Siphogenerinoides brevispinosa) and/or the ability to calcify in carbonate-corrosive waters (N. truempyi). Nuttallides truempyi, T. selmensis and other buliminids (Bolivinoides cf. decoratus group, Bulimina virginiana) were markedly abundant during the middle Ypresian. Contrary to the long-lived, highly diverse and equitable Velasco fauna, common and abundant taxa reflect highly perturbed assemblages through the earliest Ypresian, with lower diversity and equitability following the PETM extinction. In contrast, the middle Ypresian

  4. A multilocus phylogeny reveals deep lineages within African galagids (Primates: Galagidae) (United States)


    Background Bushbabies (Galagidae) are among the most morphologically cryptic of all primates and their diversity and relationships are some of the most longstanding problems in primatology. Our knowledge of galagid evolutionary history has been limited by a lack of appropriate molecular data and a paucity of fossils. Most phylogenetic studies have produced conflicting results for many clades, and even the relationships among genera remain uncertain. To clarify galagid evolutionary history, we assembled the largest molecular dataset for galagos to date by sequencing 27 independent loci. We inferred phylogenetic relationships using concatenated maximum-likelihood and Bayesian analyses, and also coalescent-based species tree methods to account for gene tree heterogeneity due to incomplete lineage sorting. Results The genus Euoticus was identified as sister taxon to the rest of the galagids and the genus Galagoides was not recovered as monophyletic, suggesting that a new generic name for the Zanzibar complex is required. Despite the amount of genetic data collected in this study, the monophyly of the family Lorisidae remained poorly supported, probably due to the short internode between the Lorisidae/Galagidae split and the origin of the African and Asian lorisid clades. One major result was the relatively old origin for the most recent common ancestor of all living galagids soon after the Eocene-Oligocene boundary. Conclusions Using a multilocus approach, our results suggest an early origin for the crown Galagidae, soon after the Eocene-Oligocene boundary, making Euoticus one of the oldest lineages within extant Primates. This result also implies that one – or possibly more – stem radiations diverged in the Late Eocene and persisted for several million years alongside members of the crown group. PMID:24694188

  5. New early Eocene vertebrate assemblage from western India reveals a mixed fauna of European and Gondwana affinities

    Directory of Open Access Journals (Sweden)

    Thierry Smith


    Full Text Available The Ypresian Cambay Shale Formation at Vastan and Mangrol lignite mines in Gujarat, western India, has yielded a rich vertebrate fauna with numerous taxa of European affinities. Here we report a new, approximately contemporary vertebrate assemblage from two fossiliferous layers in the nearby mine of Tadkeshwar. These layers have yielded a similar mammal fauna with the co-occurrence of the perissodactyl-like cambaytheriid Cambaytherium thewissi, the adapoid primates Marcgodinotius indicus and cf. Asiadapis cambayensis, and the hyaenodontid Indohyaenodon raoi. The presence of these species in both Vastan and Tadkeshwar mines and at different levels suggests that the deposits between the two major lignite seams represent a single land mammal age. Apart from the aforementioned species there is a new, smaller species of Cambaytherium, and a new genus and species of esthonychid tillodont. This fauna also contains the first large early Eocene vertebrates from India, including an unidentified Coryphodon-like pantodont, a dyrosaurid crocodyliform and a new giant madtsoiid snake. Among the Tadkeshwar vertebrates several taxa are of Gondwana affinities, such as Pelomedusoides turtles, dyrosaurids, and large madtsoiids, attesting that the early Eocene was a crucial period in India during which Laurasian taxa of European affinities co-existed with relict taxa from Gondwana before the India-Asia collision. Our results suggest that terrestrial faunas could have dispersed to or from Europe during episodes of contact between the Indian subcontinent and different island blocks along the northern margin of the Neotethys, such as the Kohistan–Ladakh island-arc system. Gondwana taxa might represent remnants of ghost lineages shared with Madagascar, which reached the Indian subcontinent during the late Cretaceous; alternatively they might have come from North Africa and passed along the southern margin of the Neotethys to reach the Indian subcontinent. These

  6. A molecular phylogeny of living primates.

    Directory of Open Access Journals (Sweden)

    Polina Perelman


    Full Text Available Comparative genomic analyses of primates offer considerable potential to define and understand the processes that mold, shape, and transform the human genome. However, primate taxonomy is both complex and controversial, with marginal unifying consensus of the evolutionary hierarchy of extant primate species. Here we provide new genomic sequence (~8 Mb from 186 primates representing 61 (~90% of the described genera, and we include outgroup species from Dermoptera, Scandentia, and Lagomorpha. The resultant phylogeny is exceptionally robust and illuminates events in primate evolution from ancient to recent, clarifying numerous taxonomic controversies and providing new data on human evolution. Ongoing speciation, reticulate evolution, ancient relic lineages, unequal rates of evolution, and disparate distributions of insertions/deletions among the reconstructed primate lineages are uncovered. Our resolution of the primate phylogeny provides an essential evolutionary framework with far-reaching applications including: human selection and adaptation, global emergence of zoonotic diseases, mammalian comparative genomics, primate taxonomy, and conservation of endangered species.

  7. A molecular phylogeny of living primates. (United States)

    Perelman, Polina; Johnson, Warren E; Roos, Christian; Seuánez, Hector N; Horvath, Julie E; Moreira, Miguel A M; Kessing, Bailey; Pontius, Joan; Roelke, Melody; Rumpler, Yves; Schneider, Maria Paula C; Silva, Artur; O'Brien, Stephen J; Pecon-Slattery, Jill


    Comparative genomic analyses of primates offer considerable potential to define and understand the processes that mold, shape, and transform the human genome. However, primate taxonomy is both complex and controversial, with marginal unifying consensus of the evolutionary hierarchy of extant primate species. Here we provide new genomic sequence (~8 Mb) from 186 primates representing 61 (~90%) of the described genera, and we include outgroup species from Dermoptera, Scandentia, and Lagomorpha. The resultant phylogeny is exceptionally robust and illuminates events in primate evolution from ancient to recent, clarifying numerous taxonomic controversies and providing new data on human evolution. Ongoing speciation, reticulate evolution, ancient relic lineages, unequal rates of evolution, and disparate distributions of insertions/deletions among the reconstructed primate lineages are uncovered. Our resolution of the primate phylogeny provides an essential evolutionary framework with far-reaching applications including: human selection and adaptation, global emergence of zoonotic diseases, mammalian comparative genomics, primate taxonomy, and conservation of endangered species.

  8. Cranial anatomy of Paleogene Micromomyidae and implications for early primate evolution. (United States)

    Bloch, Jonathan I; Chester, Stephen G B; Silcox, Mary T


    Paleogene micromomyids are small (∼10-40 g) euarchontan mammals with primate-like molars and postcrania suggestive of committed claw-climbing positional behaviors, similar to those of the extant arboreal treeshrew, Ptilocercus. Based primarily on evidence derived from dental and postcranial morphology, micromomyids have alternately been allied with plesiadapiforms, Dermoptera (colugos), or Primatomorpha (Primates + Dermoptera) within Euarchonta. Partial crania described here of Paleocene Dryomomys szalayi and Eocene Tinimomys graybulliensis from the Clarks Fork Basin of Wyoming are the first known for the family Micromomyidae. The cranium of D. szalayi exhibits a distinct, small groove near the lateral extreme of the promontorium, just medial to the fenestra vestibuli, the size of which suggests that the internal carotid artery was non-functional, as has been inferred for paromomyid and plesiadapid plesiadapiforms, but not for Eocene euprimates, carpolestids, and microsyopids. On the other hand, D. szalayi is similar to fossil euprimates and plesiadapoids in having a bullar morphology consistent with an origin that is at least partially petrosal, unlike that of paromomyids and microsyopids, although this interpretation will always be tentative in fossils that lack exhaustive ontogenetic data. Micromomyids differ from all other known plesiadapiforms in having an inflated cochlear part of the bony labyrinth and a highly pneumatized squamosal and mastoid region with associated septa. Cladistic analyses that include new cranial data, regardless of how bullar composition is coded in plesiadapiforms, fail to support either Primatomorpha or a close relationship between micromomyids and dermopterans, instead suggesting that micromomyids are among the most primitive known primates. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Lygistorrhinidae (Diptera: Bibionomorpha: Sciaroidea in early Eocene Cambay amber

    Directory of Open Access Journals (Sweden)

    Frauke Stebner


    Full Text Available One new genus and three new species of Lygistorrhinidae in early Eocene Cambay amber from India are described, which significantly increases our knowledge about this group in the Eocene. Lygistorrhina indica n. sp. is the oldest fossil known from this extant genus. Indorrhina sahnii n. gen. et sp. shows morphological similarities to each of the two extant genera Lygistorrhina and Asiorrhina. Palaeognoriste orientale is the third species known from a group that has only been recorded from Eocene Baltic amber before. The latter finding reveals faunal links between Cambay amber and the probably slightly younger Baltic amber, adding further evidence that faunal exchange between Europe/Asia and India took place before the formation of Cambay amber.

  10. Large amplitude variations in carbon cycling and terrestrial weathering during the latest Paleocene and earliest Eocene

    NARCIS (Netherlands)

    Slotnick, B.S.; Dickens, G.R.; Nicolo, M.J.; Hollis, C.J.; Crampton, J.S.; Strong, C.P.; Zachos, J.C.; Sluijs, A.; Lourens, L.; Lauretano, V.


    Global temperatures rose ~6°C from the late Paleocene ca. 58 Ma to the Early Eocene Climatic Optimum (EECO) ca. 52–50 Ma. Superimposed, were certainly two geologically brief (< 200 kyr) intervals of extreme warming, the Paleocene-Eocene thermal maximum (PETM) and Eocene thermal maximum 2 (ETM-2

  11. A diverse Eocene fish scale assemblage from Seymour Island, Antarctica

    Czech Academy of Sciences Publication Activity Database

    Přikryl, Tomáš; Vodrážka, R.


    Roč. 34, č. 4 (2012), s. 895-908 ISSN 1280-9659 Institutional research plan: CEZ:AV0Z30130516 Institutional support: RVO:67985831 Keywords : Teleostei * scales * lepidology * Eocene * La Meseta Formation Subject RIV: DB - Geology ; Mineralogy Impact factor: 0.927, year: 2012

  12. Molecular composition and paleobotanical origin of Eocene resin ...

    Indian Academy of Sciences (India)

    characteristic of warm tropical climate suggesting the prevalence of such climate during early Eocene in northeast India. 1. Introduction ... family (Dutta et al. 2009, 2011b). These are also known as dammar resins and have been classified as Class II resins (Anderson et al. 1992; Dutta et al. 2009). These have been reported ...

  13. Multiple states in the late Eocene ocean circulation

    NARCIS (Netherlands)

    M.L.J. Baatsen; A.S. von der Heydt; M. Kliphuis; J.P. Viebahn (Jan); H.A. Dijkstra


    htmlabstractThe Eocene-Oligocene Transition (EOT) marks a major step within the Cenozoic climate in going from a greenhouse into an icehouse state, with the formation of a continental-scale Antarctic ice sheet. The roles of steadily decreasing CO2 concentrations versus changes in ocean

  14. High bat (Chiroptera) diversity in the Early Eocene of India (United States)

    Smith, Thierry; Rana, Rajendra S.; Missiaen, Pieter; Rose, Kenneth D.; Sahni, Ashok; Singh, Hukam; Singh, Lachham


    The geographic origin of bats is still unknown, and fossils of earliest bats are rare and poorly diversified, with, maybe, the exception of Europe. The earliest bats are recorded from the Early Eocene of North America, Europe, North Africa and Australia where they seem to appear suddenly and simultaneously. Until now, the oldest record in Asia was from the Middle Eocene. In this paper, we report the discovery of the oldest bat fauna of Asia dating from the Early Eocene of the Cambay Formation at Vastan Lignite Mine in Western India. The fossil taxa are described on the basis of well-preserved fragments of dentaries and lower teeth. The fauna is highly diversified and is represented by seven species belonging to seven genera and at least four families. Two genera and five species are new. Three species exhibit very primitive dental characters, whereas four others indicate more advanced states. Unexpectedly, this fauna presents strong affinities with the European faunas from the French Paris Basin and the German Messel locality. This could result from the limited fossil record of bats in Asia, but could also suggest new palaeobiogeographic scenarios involving the relative position of India during the Early Eocene.

  15. Late Paleocene–early Eocene carbon isotope stratigraphy from a ...

    Indian Academy of Sciences (India)

    ) witnessed a series of short-lived hyperthermal events (Paleocene–Eocene thermal maximum (PETM), H1/ETM2/ELMO, H2, I1, and I2), superimposed on the long-term global warming trend (Cramer et al. 2003; Nicolo et al. 2007; Zachos et al.

  16. Maastrichtian Paleocene and Eocene pollen and spores from Nigeria

    NARCIS (Netherlands)

    Hoeken-Klinkenberg, van P.M.J.


    In order to continue the investigation of the Nigerian Maastrichtian pollenflora (van Hoeken-Klinkenberg, 1964) with Lower Tertiary material, a study has been made of some boreholesamples of the Maastrichtian, Paleocene and Eocene in Nigeria. A comparison is made with the South American pollen and

  17. Scaled biotic disruption during early Eocene global warming events

    Directory of Open Access Journals (Sweden)

    S. J. Gibbs


    Full Text Available Late Paleocene and early Eocene hyperthermals are transient warming events associated with massive perturbations of the global carbon cycle, and are considered partial analogues for current anthropogenic climate change. Because the magnitude of carbon release varied between the events, they are natural experiments ideal for exploring the relationship between carbon cycle perturbations, climate change and biotic response. Here we quantify marine biotic variability through three million years of the early Eocene that include five hyperthermals, utilizing a method that allows us to integrate the records of different plankton groups through scenarios ranging from background to major extinction events. Our long time-series calcareous nannoplankton record indicates a scaling of biotic disruption to climate change associated with the amount of carbon released during the various hyperthermals. Critically, only the three largest hyperthermals, the Paleocene–Eocene Thermal Maximum (PETM, Eocene Thermal Maximum 2 (ETM2 and the I1 event, show above-background variance, suggesting that the magnitude of carbon input and associated climate change needs to surpass a threshold value to cause significant biotic disruption.

  18. Towards a robust and consistent middle Eocene astronomical timescale (United States)

    Boulila, Slah; Vahlenkamp, Maximilian; De Vleeschouwer, David; Laskar, Jacques; Yamamoto, Yuhji; Pälike, Heiko; Kirtland Turner, Sandra; Sexton, Philip F.; Westerhold, Thomas; Röhl, Ursula


    Until now, the middle Eocene has remained a poorly constrained interval of efforts to produce an astrochronological timescale for the entire Cenozoic. This has given rise to a so-called "Eocene astronomical timescale gap" (Vandenberghe et al., 2012). A high-resolution astrochronological calibration for this interval has proven to be difficult to realize, mainly because carbonate-rich deep-marine sequences of this age are scarce. In this paper, we present records from middle Eocene carbonate-rich sequences from the North Atlantic Southeast Newfoundland Ridge (IODP Exp. 342, Sites U1408 and U1410), of which the cyclical sedimentary patterns allow for an orbital calibration of the geologic timescale between ∼38 and ∼48 Ma. These carbonate-rich cyclic sediments at Sites U1408 and U1410 were deposited as drift deposits and exhibit prominent lithological alternations (couplets) between greenish nannofossil-rich clay and white nannofossil ooze. The principal lithological couplet is driven by the obliquity of Earth's axial tilt, and the intensity of their expression is modulated by a cyclicity of about 173 kyr. This cyclicity corresponds to the interference of secular frequencies s3 and s6 (related to the precession of nodes of the Earth and Saturn, respectively). This 173-kyr obliquity amplitude modulation cycle is exceptionally well recorded in the XRF (X-ray fluorescence)-derived Ca/Fe ratio. In this work, we first demonstrate the stability of the (s3-s6) cycles using the latest astronomical solutions. Results show that this orbital component is stable back to at least 50 Ma, and can thus serve as a powerful geochronometer in the mid-Eocene portion of the Cenozoic timescale. We then exploit this potential by calibrating the geochronology of the recovered middle Eocene timescale between magnetic polarity Chrons C18n.1n and C21n. Comparison with previous timescales shows similarities, but also notable differences in durations of certain magnetic polarity chrons. We

  19. Cellular scaling rules for primate brains


    Herculano-Houzel, Suzana; Collins, Christine E.; Wong, Peiyan; Kaas, Jon H.


    Primates are usually found to have richer behavioral repertoires and better cognitive abilities than rodents of similar brain size. This finding raises the possibility that primate brains differ from rodent brains in their cellular composition. Here we examine the cellular scaling rules for primate brains and show that brain size increases approximately isometrically as a function of cell numbers, such that an 11× larger brain is built with 10× more neurons and ≈12× more nonneuronal cells of ...

  20. Eocene cooling linked to early flow across the Tasmanian Gateway. (United States)

    Bijl, Peter K; Bendle, James A P; Bohaty, Steven M; Pross, Jörg; Schouten, Stefan; Tauxe, Lisa; Stickley, Catherine E; McKay, Robert M; Röhl, Ursula; Olney, Matthew; Sluijs, Appy; Escutia, Carlota; Brinkhuis, Henk


    The warmest global temperatures of the past 85 million years occurred during a prolonged greenhouse episode known as the Early Eocene Climatic Optimum (52-50 Ma). The Early Eocene Climatic Optimum terminated with a long-term cooling trend that culminated in continental-scale glaciation of Antarctica from 34 Ma onward. Whereas early studies attributed the Eocene transition from greenhouse to icehouse climates to the tectonic opening of Southern Ocean gateways, more recent investigations invoked a dominant role of declining atmospheric greenhouse gas concentrations (e.g., CO2). However, the scarcity of field data has prevented empirical evaluation of these hypotheses. We present marine microfossil and organic geochemical records spanning the early-to-middle Eocene transition from the Wilkes Land Margin, East Antarctica. Dinoflagellate biogeography and sea surface temperature paleothermometry reveal that the earliest throughflow of a westbound Antarctic Counter Current began ~49-50 Ma through a southern opening of the Tasmanian Gateway. This early opening occurs in conjunction with the simultaneous onset of regional surface water and continental cooling (2-4 °C), evidenced by biomarker- and pollen-based paleothermometry. We interpret that the westbound flowing current flow across the Tasmanian Gateway resulted in cooling of Antarctic surface waters and coasts, which was conveyed to global intermediate waters through invigorated deep convection in southern high latitudes. Although atmospheric CO2 forcing alone would provide a more uniform middle Eocene cooling, the opening of the Tasmanian Gateway better explains Southern Ocean surface water and global deep ocean cooling in the apparent absence of (sub-) equatorial cooling.

  1. Eocene cooling linked to early flow across the Tasmanian Gateway (United States)

    Bijl, Peter K.; Bendle, James A. P.; Bohaty, Steven M.; Pross, Jörg; Schouten, Stefan; Tauxe, Lisa; Stickley, Catherine E.; McKay, Robert M.; Röhl, Ursula; Olney, Matthew; Sluijs, Appy; Escutia, Carlota; Brinkhuis, Henk; Klaus, Adam; Fehr, Annick; Williams, Trevor; Carr, Stephanie A.; Dunbar, Robert B.; Gonzàlez, Jhon J.; Hayden, Travis G.; Iwai, Masao; Jimenez-Espejo, Francisco J.; Katsuki, Kota; Kong, Gee Soo; Nakai, Mutsumi; Passchier, Sandra; Pekar, Stephen F.; Riesselman, Christina; Sakai, Toyosaburo; Shrivastava, Prakash K.; Sugisaki, Saiko; Tuo, Shouting; van de Flierdt, Tina; Welsh, Kevin; Yamane, Masako


    The warmest global temperatures of the past 85 million years occurred during a prolonged greenhouse episode known as the Early Eocene Climatic Optimum (52–50 Ma). The Early Eocene Climatic Optimum terminated with a long-term cooling trend that culminated in continental-scale glaciation of Antarctica from 34 Ma onward. Whereas early studies attributed the Eocene transition from greenhouse to icehouse climates to the tectonic opening of Southern Ocean gateways, more recent investigations invoked a dominant role of declining atmospheric greenhouse gas concentrations (e.g., CO2). However, the scarcity of field data has prevented empirical evaluation of these hypotheses. We present marine microfossil and organic geochemical records spanning the early-to-middle Eocene transition from the Wilkes Land Margin, East Antarctica. Dinoflagellate biogeography and sea surface temperature paleothermometry reveal that the earliest throughflow of a westbound Antarctic Counter Current began ∼49–50 Ma through a southern opening of the Tasmanian Gateway. This early opening occurs in conjunction with the simultaneous onset of regional surface water and continental cooling (2–4 °C), evidenced by biomarker- and pollen-based paleothermometry. We interpret that the westbound flowing current flow across the Tasmanian Gateway resulted in cooling of Antarctic surface waters and coasts, which was conveyed to global intermediate waters through invigorated deep convection in southern high latitudes. Although atmospheric CO2 forcing alone would provide a more uniform middle Eocene cooling, the opening of the Tasmanian Gateway better explains Southern Ocean surface water and global deep ocean cooling in the apparent absence of (sub-) equatorial cooling. PMID:23720311

  2. A terrestrial Eocene stack: tying terrestrial lake ecology to marine carbon cycling through the Early Eocene Climatic Optimum (United States)

    Grogan, D. S.; Whiteside, J. H.; Musher, D.; Rosengard, S. Z.; Vankeuren, M. A.; Pancost, R. D.


    The lacustrine Green River Formation is known to span ≥15 million years through the early-middle Eocene, and recent work on radioisotopic dating has provided a framework on which to build ties to the orbitally-tuned marine Eocene record. Here we present a spliced stack of Fischer assay data from drilled cores of the Green River Formation that span both an East-West and a North-South transect of the Uinta Basin of Utah. Detailed work on two cores demonstrate that Fischer assay measurements covary with total organic carbon and bulk carbon isotopes, allowing us to use Fisher assay results as a representative carbon cycling proxy throughout the stack. We provide an age model for this core record by combining radioisotopic dates of tuff layers with frequency analysis of Fischer assay measurements. Identification of orbital frequencies tied directly to magnetochrons through radioisotopic dates allows for a direct comparison of the terrestrial to the marine Eocene record. Our analysis indicates that the marker beds used to correlate the stack cores represent periods of enhanced lake productivity and extreme carbon burial; however, unlike the hyperthermal events that are clearly marked in the marine Eocene record, the hydrocarbon-rich "Mahogany Bed" period of burial does not correspond to a clear carbon isotope excursion. This suggests that the terrestrial realm may have experienced extreme ecological responses to relatively small perturbations in the carbon cycle during the Early Eocene Climatic Optimum. To investigate the ecological responses to carbon cycle perturbations through the hydrocarbon rich beds, we analyzed a suite of microbial biomarkers, finding evidence for cyanobacteria, dinoflagellates, and potentially green sulfur bacteria. These taxa indicate fluctuating oxic/anoxic conditions in the lake during abrupt intervals of carbon burial, suggesting a lake biogeochemical regime with no modern analogues.

  3. Bion 11 mission: primate experiments (United States)

    Ilyin, E. A.; Korolkov, V. I.; Skidmore, M. G.; Viso, M.; Kozlovskaya, I. B.; Grindeland, R. E.; Lapin, B. A.; Gordeev, Y. V.; Krotov, V. P.; Fanton, J. W.; hide


    A summary is provided of the major operations required to conduct the wide range of primate experiments on the Bion 11 mission, which flew for 14 days beginning December 24, 1996. Information is given on preflight preparations, including flight candidate selection and training; attachment and implantation of bioinstrumentation; flight and ground experiment designs; onboard life support and test systems; ground and flight health monitoring; flight monkey selection and transport to the launch site; inflight procedures and data collection; postflight examinations and experiments; and assessment of results.

  4. Paleocene-Eocene Thermal Maximum (PETM) and its Effects on Continental Biotas: Evidence from Polecat Bench in Northwestern Wyoming (United States)

    Gingerich, P. D.


    Many important environmental events in the geological past were first recognized by their effects on the associated biota, and this is true for the Paleocene-Eocene Thermal Maximum or PETM global greenhouse warming event, which happened 55 million years before present. In the Southern Ocean, PETM carbon and oxygen isotope anomalies were found to coincide with a major terminal-Paleocene disappearance or extinction of benthic foraminiferans. On North America the PETM carbon isotope excursion (CIE) was found to coincide with mammalian dwarfing and a major initial-Eocene appearance or origination event of continental mammals. Linking the two records, marine and continental, resolved a long-standing disagreement over competing definitions of the Paleocene-Eocene epoch boundary, and more importantly indicated that the PETM greenhouse warming event was global. Dwarfing of herbivorous mammals can be interpreted as a response to elevated atmospheric CO2. The origin of modern orders of mammals including Artiodactyla, Perissodactyla, and Primates ('APP' taxa) is more complicated and difficult to explain but the origin of these orders may also be a response, directly or indirectly, to PETM warming. We now know from Polecat Bench and elsewhere in North America that the biotic response to PETM greenhouse warming involved the appearance of at least two new mammalian faunas distinct from previously known Clarkforkian mammals of the upper or late Paleocene and previously known Wasatchian mammals of the lower or early Eocene. Three stages and ages of the former are known (Cf-1 to Cf-3) and seven stages and ages of the latter are known (Wa-1 to Wa-7), each occupying about a hundred meters of strata representing a half-million years or so of time. Between the standard Clarkforkian and Wasatchian faunal zones is an initial 'Wa-M' faunal zone of only five or so meters in thickness and something on the order of 20 thousand years of geological time. The Wa-M fauna includes the first

  5. Asian Eocene monsoons as revealed by leaf architectural signatures (United States)

    Spicer, Robert A.; Yang, Jian; Herman, Alexei B.; Kodrul, Tatiana; Maslova, Natalia; Spicer, Teresa E. V.; Aleksandrova, Galina; Jin, Jianhua


    The onset and development of the Asian monsoon systems is a topic that has attracted considerable research effort but proxy data limitations, coupled with a diversity of definitions and metrics characterizing monsoon phenomena, have generated much debate. Failure of geological proxies to yield metrics capable of distinguishing between rainfall seasonality induced by migrations of the Inter-tropical Convergence Zone (ITCZ) from that attributable to topographically modified seasonal pressure reversals has frustrated attempts to understand mechanisms underpinning monsoon development and dynamics. Here we circumvent the use of such single climate parameter metrics in favor of detecting directly the distinctive attributes of different monsoon regimes encoded in leaf fossils. Leaf form adapts to the prevailing climate, particularly under the extreme seasonal stresses imposed by monsoons, so it is likely that fossil leaves carry a unique signature of past monsoon regimes. Leaf form trait spectra obtained from fossils from Eocene basins in southern China were compared with those seen in modern leaves growing under known climate regimes. The fossil leaf trait spectra, including those derived from previously published fossil floras from northwestern India, were most similar to those found in vegetation exposed to the modern Indonesia-Australia Monsoon (I-AM), which is largely a product of seasonal migrations of the ITCZ. The presence of this distinctive leaf physiognomic signature suggests that although a monsoon climate existed in Eocene time across southern Asia the characteristics of the modern topographically-enhanced South Asia Monsoon had yet to develop. By the Eocene leaves in South Asia had become well adapted to an I-AM type regime across many taxa and points to the existence of a pervasive monsoon climate prior to the Eocene. No fossil trait spectra typical of exposure to the modern East Asia monsoon were seen, suggesting the effects of this system in southern

  6. Eocene Hyperthermal Climate Sensitivity to Greenhouse Gas and Aerosol Forcing (United States)

    Winguth, A. M. E.; Hughlett, T. M.; Brown, M.; Rothstein, M.; Shields, C. A.; Winguth, C.


    A series of DeepMIP climate sensitivity experiments have been carried out with the Community Earth System Model CESM1.2 to evaluate how changes in the radiative forcing could have contributed to explain Eocene hyperthermal events. A rise in Eocene greenhouse gas forcing could have been linked to an increase in volcanism and associated destabilization of marine carbon reservoirs by dissociation of clathrathes, reorganization of the marine microbial loop, or terrestrial sources from e.g. wetlands. Such environmental changes could potentially have led to additional biophysical feedbacks altering the cloud aerosol optical depth for example by alteration of marine plankton productivity and DMS emissions to the atmosphere. The analysis of our simulations suggests a substantial warming from 3x to 12x CO2 PAL, reaching moderate temperatures of up to 20 °C over Antarctica and in the Article realm in the most extreme scenario, consistent to proxy estimates in a high CO2 world. The lower equator-to-pole temperature gradient compared to present-day is due to the lack of an ice sheet, an increase in greenhouse gases, and a lower cloud optical depth. The climate simulations suggest an intensified hydrological cycle with higher precipitation in the tropics, particularly over the Indian Eocene continent, and in mid-latitudes, whereas mega-droughts are prominent in the subtropics, particularly in Africa and South America. The Eocene geography (the closure of the Drake Passage and the more southern location of Australia) and a lower-than-present meridional temperature gradient contribute to a much weaker surface ocean circulation near the Antarctic continent as compared to the current pronounced Antarctic Circumpolar Current.

  7. Multiple states in the late Eocene ocean circulation (United States)

    Baatsen, M. L. J.; von der Heydt, A. S.; Kliphuis, M.; Viebahn, J.; Dijkstra, H. A.


    The Eocene-Oligocene Transition (EOT) marks a major step within the Cenozoic climate in going from a greenhouse into an icehouse state, with the formation of a continental-scale Antarctic ice sheet. The roles of steadily decreasing CO2 concentrations versus changes in ocean circulation at the EOT are still debated and the threshold for Antarctic glaciation is obscured by uncertainties in global geometry. Here, a detailed study of the late Eocene ocean circulation is carried out using an ocean general circulation model under two slightly different geography reconstructions of the middle-to-late Eocene (38 Ma). Using the same atmospheric forcing, both geographies give a profoundly different equilibrium ocean circulation state. The underlying reason for this sensitivity is the presence of multiple equilibria characterised by either North or South Pacific deep water formation. A possible shift from a southern towards a northern overturning circulation would result in significant changes in the global heat distribution and consequently make the Southern Hemisphere climate more susceptible for significant cooling and ice sheet formation on Antarctica.

  8. Passifloraceae seeds from the late Eocene of Colombia. (United States)

    Martínez, Camila


    The plant fossil record for the neotropics is still sparse and temporally discontinuous. The location and description of new fossil material are fundamental for understanding evolutionary and biogeographic patterns of lineages. A new fossil record of Passifloraceae from the late Eocene of Colombia is described in this study. Plant fossils were collected from a new locality from the Eocene Esmeraldas Formation. Eighteen fossil seeds were selected, described, and compared with fossil and extant angiosperm seeds based on the literature and herbarium collections. Taxonomic affinities of the fossil seeds within Passifloraceae s.l. were evaluated by comparing morphological characters of the seeds in a phylogenetic context. Stratigraphic information associated with the fossil locality was used to interpret the environment and taphonomic processes associated with fossil deposition. A new seed fossil genus and species, Passifloroidesperma sogamosense gen. and sp. nov., is described and associated with the subfamily Passifloroideae based on the presence of a foveolate seed surface, ruminate endosperm, and a seed coat with prismatic palisade cells. The depositional environment of the locality is described as a floodplain associated with river channels. A detailed review of the Passifloraceae fossil record indicates that P. sogamosense is the oldest confirmed record of Passifloraceae. Its late Eocene age provides a minimum age that can be used as a calibration point for the crown Passifloroideae node in future dating analyses that together with its neotropical geographic location can shed light on the origin and diversification of the subfamily. © 2017 Botanical Society of America.

  9. Eocene diversification of crown group rails (Aves: Gruiformes: Rallidae.

    Directory of Open Access Journals (Sweden)

    Juan C García-R

    Full Text Available Central to our understanding of the timing of bird evolution is debate about an apparent conflict between fossil and molecular data. A deep age for higher level taxa within Neoaves is evident from molecular analyses but much remains to be learned about the age of diversification in modern bird families and their evolutionary ecology. In order to better understand the timing and pattern of diversification within the family Rallidae we used a relaxed molecular clock, fossil calibrations, and complete mitochondrial genomes from a range of rallid species analysed in a Bayesian framework. The estimated time of origin of Rallidae is Eocene, about 40.5 Mya, with evidence of intrafamiliar diversification from the Late Eocene to the Miocene. This timing is older than previously suggested for crown group Rallidae, but fossil calibrations, extent of taxon sampling and substantial sequence data give it credence. We note that fossils of Eocene age tentatively assigned to Rallidae are consistent with our findings. Compared to available studies of other bird lineages, the rail clade is old and supports an inference of deep ancestry of ground-dwelling habits among Neoaves.

  10. Life history of the most complete fossil primate skeleton: exploring growth models for Darwinius (United States)

    López-Torres, Sergi; Schillaci, Michael A.; Silcox, Mary T.


    Darwinius is an adapoid primate from the Eocene of Germany, and its only known specimen represents the most complete fossil primate ever found. Its describers hypothesized a close relationship to Anthropoidea, and using a Saimiri model estimated its age at death. This study reconstructs the ancestral permanent dental eruption sequences for basal Euprimates, Haplorhini, Anthropoidea, and stem and crown Strepsirrhini. The results show that the ancestral sequences for the basal euprimate, haplorhine and stem strepsirrhine are identical, and similar to that of Darwinius. However, Darwinius differs from anthropoids by exhibiting early development of the lower third molars relative to the lower third and fourth premolars. The eruption of the lower second premolar marks the point of interruption of the sequence in Darwinius. The anthropoid Saimiri as a model is therefore problematic because it exhibits a delayed eruption of P2. Here, an alternative strepsirrhine model based on Eulemur and Varecia is presented. Our proposed model shows an older age at death than previously suggested (1.05–1.14 years), while the range for adult weight is entirely below the range proposed previously. This alternative model is more consistent with hypotheses supporting a stronger relationship between adapoids and strepsirrhines. PMID:26473056

  11. Modern Mammals dispersion linked to the Paleocene Eocene thermal maximum (PETM) and early Eocene climatic optimum, new insights from India (United States)

    Khozyem, H. M.; Adatte, T.; Keller, G.; Spangenberg, J.; Bajpai, S.; Samant, B.


    The Paleocene Eocene Thermal Maximum (PETM, 55.9Ma)) is globally related with the extinction of deep benthic foraminifera, the diversification of both planktic foraminifera and modern mammals. In India, the tempo and timing of modern mammal dispersion, their association with the PETM or EECO (Early Eocene Climatic Optimum) and the India-Asia collision remain uncertain. Four Indian sections (Giral, Bhavnagar, Vastan and Tadkeshware lignite mines) have been studied using sedimentology, micropaleontology, mineralogy (bulk and clay mineralogy) and geochemistry (stable isotopes, major and trace elements, organic matter). Both PETM and ETM2 (second Eocene Thermal Maximum, 53.7Ma), a short-lived warming episode that followed the PETM, are globally marked by a pronounced δ13Ccarb and δ13Corg negative excursion. Both isotopic excursions have been recognized in the Vastan and Tarkeswhar lignite mines (Cambay basin, Gujarat) associated with the main mammal bearing level. The lower shift is located above the first lignite seam and corresponds to the transition from continental to shallow marine conditions. The upper excursion appears to be linked to the ETM2 and corresponds to a second marine incursion containing bivalves, benthic (Nummulites burdigalensis) and planktic foraminifera located below the second lignite seam. A very pronounced δ13Corg peak has been detected in the Giral lignite mine (Barmer, Rajhastan) around 6m above the vertebrate bearing level and may correspond to the PETM. This correlation is confirmed by palynological data and more particularly by a dinoflagellate acme that globally characterizes the PETM interval. Our micropaleontological data combined with stable carbone isotopes indicate the presence of both PETM and ETM2 events and constrain the age of the early mammals in northwestern India in between these two thermal events in the early Eocene. These new data will significantly improve the ongoing debate on whether mammals originated in or out of

  12. Comparing primate crania: The importance of fossils. (United States)

    Fleagle, John G; Gilbert, Christopher C; Baden, Andrea L


    Extant primate crania represent a small subset of primate crania that have existed. The main objective here is to examine how the inclusion of fossil crania changes our understanding of primate cranial diversity relative to analyses of extant primates. We hypothesize that fossil taxa will change the major axes of cranial shape, occupy new areas of morphospace, change the relative diversity of major primate clades, and fill in notable gaps separating major primate taxa/clades. Eighteen 3D landmarks were collected on 157 extant and fossil crania representing 90 genera. Data were subjected to a Generalized Procrustes Analysis then principal components analysis. Relative diversity between clades was assessed using an F-statistic. Fossil taxa do not significantly alter major axes of cranial shape, but they do occupy unique areas of morphospace, change the relative diversity between clades, and fill in notable gaps in primate cranial evolution. Strepsirrhines remain significantly less diverse than anthropoids. Fossil hominins fill the gap in cranial morphospace between extant great apes and modern humans. The morphospace outlined by living primates largely includes that occupied by fossil taxa, suggesting that the cranial diversity of living primates generally encompasses the total diversity that has evolved in this Order. The evolution of the anthropoid cranium was a significant event allowing anthropoids to achieve significantly greater cranial diversity compared to strepsirrhines. Fossil taxa fill in notable gaps within and between clades, highlighting their transitional nature and eliminating the appearance of large morphological distances between extant taxa, particularly in the case of extant hominids. © 2016 Wiley Periodicals, Inc.

  13. Jean-Jacques Petter. Primates

    Directory of Open Access Journals (Sweden)

    Bruno Simmen


    Full Text Available Voici un magnifique ouvrage grand format sur les Primates dont l’auteur principal est le regretté Jean Jacques Petter, l’un des spécialistes historiques des prosimiens de Madagascar. Ce livre, publié à titre posthume, a une histoire que nous découvrons dans la préface d’Yves Coppens. A l’origine pensé et rédigé par Jean-Jacques Petter, qui a été professeur au Muséum National d’Histoire Naturelle, l’ouvrage interrompu à sa mort en 2002 a été remis en chantier sous l’impulsion de sa femme Arlet...

  14. Phylogeny, paleontology, and primates: do incomplete fossils bias the tree of life? (United States)

    Pattinson, David J; Thompson, Richard S; Piotrowski, Aleks K; Asher, Robert J


    Paleontological systematics relies heavily on morphological data that have undergone decay and fossilization. Here, we apply a heuristic means to assess how a fossil's incompleteness detracts from inferring its phylogenetic relationships. We compiled a phylogenetic matrix for primates and simulated the extinction of living species by deleting an extant taxon's molecular data and keeping only those morphological characters present in actual fossils. The choice of characters present in a given living taxon (the subject) was defined by those present in a given fossil (the template). By measuring congruence between a well-corroborated phylogeny to those incorporating artificial fossils, and by comparing real vs. random character distributions and states, we tested the information content of paleontological datasets and determined if extinction of a living species leads to bias in phylogeny reconstruction. We found a positive correlation between fossil completeness and topological congruence. Real fossil templates sampled for 36 or more of the 360 available morphological characters (including dental) performed significantly better than similarly complete templates with random states. Templates dominated by only one partition performed worse than templates with randomly sampled characters across partitions. The template based on the Eocene primate Darwinius masillae performs better than most other templates with a similar number of sampled characters, likely due to preservation of data across multiple partitions. Our results support the interpretation that Darwinius is strepsirhine, not haplorhine, and suggest that paleontological datasets are reliable in primate phylogeny reconstruction. © The Author(s) 2014. Published by Oxford University Press, on behalf of the Society of Systematic Biologists. All rights reserved. For Permissions, please email:

  15. Deep Hierarchies in the Primate Visual Cortex

    DEFF Research Database (Denmark)

    Krüger, Norbert; Jannsen, Per; Kalkan, S.


    of the processing hierarchies present in the primate visual system considering recent discoveries in neurophysiology. The hierarchal processing in the primate visual system is characterized by a sequence of different levels of processing (in the order of ten) that constitute a deep hierarchy in contrast to the flat...... vision architectures predominantly used in today's mainstream computer vision. We hope that the functional description of the deep hierarchies realized in the primate visual system provides valuable insights for the design of computer vision algorithms, fostering increasingly productive interaction......Computational modeling of the primate visual system yields insights of potential relevance to some of the challenges that computer vision is facing, such as object recognition and categorization, motion detection and activity recognition or vision-based navigation and manipulation. This article...

  16. Personality, social hierarchy and hormones in primates


    KONEČNÁ, Martina


    This thesis deals with two main issues: personality (stable individual differences in behavior) and behavioral endocrinology (or socioendocrinology) in nonhuman primates. The first part of the thesis comprises of two primate personality studies of two species: Hanuman langurs and Barbary macaques. Two basic methods of animal personality research (behavioral coding and trait rating) were compared. Stability of personality assessments has been demonstrated. Social rank of individuals was used t...

  17. Profundal sideritic mudstone from an Eocene lake in Alaska

    International Nuclear Information System (INIS)

    Dickinson, K.A.


    Sideritic lacustrine mudstone was found in drill core from a uranium deposit in the Death Valley area in the eastern part of the Seward Peninsula, Alaska. The precursor sediments for this rock were deposited in an unusual iron-meromictic Eocene lake, herein named Lake Tubutulik, which occupied part of the Boulder Creek basin, a graben that is probably a southern extension of the larger Death Valley basin. The Boulder Creek basin is bounded on the west by granite of the Upper Cretaceous Darby pluton and on the east by Precambrian to Paleozoic metasedimentary rocks. The lake basin was formed by basaltic flows that dammed the valley of the ancestral Tubutulik River in early Eocene time. The lake sediments included a nearshore facies of fine-grained organic mud and an offshore facies of laminated sideritic mud. The offshore (profundal) laminated mudstone consists of alternating layers of authigenic siderite and detrital grains, mostly quartz and clay minerals. Both lacustrine facies contain turbidites. The lacustrine rocks graded laterally into an onshore facies of colluvial and fluvial sandstone, paludal mudstone, and coal. The ancient lake occupied a small, deep basin in a tectonically active area of high relief. Meromixis was apparently stabilized by reduced iron and bicarbonate dissolved in the monimolimnion. The intensity of meromixis decreased as the lake became shallower from sediment filling. The source of the dissolved iron in the monoimolimnion was probably the Eocene basalt. Carbon isotope analysis of the siderite suggests that the dissolved bicarbonate in the profundal facies was largely inorganic. Sideritic carbon in one sample from the onshore paludal facies has an isotopic signature (δ 13 C = +16.9) consistent with residual carbonate formed during methanogenic fermentation

  18. Orbital forcing of the Paleocene and Eocene carbon cycle (United States)

    Zeebe, Richard E.; Westerhold, Thomas; Littler, Kate; Zachos, James C.


    Multimillion-year proxy records across the Paleocene and Eocene show prominent variations on orbital time scales. The cycles, which have been identified at various sites across the globe, preferentially concentrate spectral power at eccentricity and precessional frequencies. It is evident that these cycles are an expression of changes in global climate and carbon cycling paced by astronomical forcing. However, little is currently known about the link between orbital forcing and the carbon cycle-climate system and the amplitude of associated atmospheric CO2 variations. Here we use simple and complex carbon cycle models to explore the basic effect of different orbital forcing schemes and noise on the carbon cycle. Our primary modeling target is the high-resolution, ˜7.7 Myr long, benthic isotope record at Ocean Drilling Program Site 1262 in the South Atlantic. For direct insolation forcing (as opposed to artificial eccentricity-tilt-precession), one major challenge is understanding how the system transfers spectral power from high to low frequencies. We discuss feasible solutions, including insolation transformations analogous to electronic AC-DC conversion (DC'ing). Regarding mechanisms, we focus on tropical insolation and a long-term carbon imbalance in terrestrial organic burial/oxidation but do not rule out other scenarios. Our analysis shows that high-latitude mechanisms are unlikely drivers of orbitally paced changes in the late Paleocene-early Eocene (LPEE) Earth system. Furthermore, we provide constraints on the origin and isotopic composition of a possible LPEE cyclic carbon imbalance/source responding to astronomical forcing. Our simulations also reveal a mechanism for the large δ13C-eccentricity lag at the 400 kyr period observed in Paleocene, Oligocene, and Miocene sections. We present the first estimates of orbital-scale variations in atmospheric CO2 during the late Paleocene and early Eocene.

  19. Connecting America and Russia: Eocene erosion across the Arctic (United States)

    Spiegel, Cornelia; Lisker, Frank; Piepjohn, Karsten; Estrada, Solveig; Lorenz, Henning


    The structural evolution of the Arctic Ocean and its surrounding continental areas is still poorly constrained, due to ice coverage and inaccessibility. The only scientific coring campaign within the central Arctic Ocean (the ACEX project) was positioned on the Lomonosov Ridge. This is a pronounced geomorphic structure of presumably continental origin, which stretches across the entire Arctic Ocean between the northernmost margin of the North American continent (Ellesmere Island) and the Siberian Shelf, bordering the New Siberian Islands. Geophysical data suggest that the Lomonosov Ridge may be continuous with the Siberian and Ellesmerian continental margins (e.g., Poselov et al., 2011). Rather unexpectedly, the ACEX project revealed that the Lomonosov Ridge was in very shallow water or even exposed to erosion between 44 and 18 Ma. As an explanation, it was suggested that the Lomonosov Ridge experienced compressional tectonics at that time, which may have affected the entire central Arctic Ocean, propagating from North America towards the Siberian shelf (ÓRegan et al., 2008). Here we present the first low-temperature thermochronological data from northern Ellesmere Island and from the New Siberian Islands, recording the erosion and exhumation history of these areas. Our apatite (U-Th)/He data show that while southern and central Ellesmere Island was characterized by very slow erosion during the Cenozoic, northern Ellesmere Island bordering the Arctic Ocean experienced km-scale erosion during the Eocene, contemporaneously with the stalled subsidence / uplift period of the Lomonosov Ridge. The thermochronology data from the New Siberian Islands reflect a complex erosion history: the eastern part of the North Siberian Islands, the DeLong Island Group, experienced rather limited erosion during the Cenozoic and most of the Mesozoic. By contrast, data from the western New Siberian Islands - the Lyakhov Island Group - in direct continuation of the Lomonosov Ridge are

  20. A new burmagomphid dragonfly from the Eocene of Patagonia, Argentina

    Directory of Open Access Journals (Sweden)

    Julián F. Petrulevičius


    Full Text Available A new burmagomphid anisopteran, Satelitala soberana gen. et sp. nov. is described from the lower Eocene of Laguna del Hunco, Patagonia, Argentina. The new genus is characterised by hindwing characters such as the subdiscoidal triangle not elongated; anal loop divided longitudinally; paranal cell divided longitudinally; five terminal cells between RP and MA; five terminal cells between MP and CuA; and obtuse angle between PsA and CuP+AA. Burmagomphid dragonflies were represented so far only by one specimen from the middle Cretaceous of Southeast Asia. This new record extends the distribution to Patagonia, to the Cenozoic, and also to paleolake deposits.

  1. Natural product terpenoids in Eocene and Miocene conifer fossils. (United States)

    Otto, Angelika; White, James D; Simoneit, Bernd R T


    Numerous saturated and aromatic hydrocarbons, but not polar compounds, originating from plants and microorganisms (biomarkers) have been reported in sediments, coals, and petroleum. Here we describe natural product terpenoids found in two fossil conifers, Taxodium balticum (Eocene) and Glyptostrobus oregonensis (Miocene). A similar terpenoid pattern is also observed in extant Taxodium distichum. The preservation of characteristic terpenoids (unaltered natural products) in the fossil conifers supports their systematic assignment to the Cypress family (Cupressaceae sensu lato). The results also show that fossil conifers can contain polar terpenoids, which are valuable markers for (paleo)chemosystematics and phylogeny.

  2. Aridification in continental Asia after the Middle Eocene Climatic Optimum (MECO)

    NARCIS (Netherlands)

    Bosboom, R.E.|info:eu-repo/dai/nl/322947359; Abels, H.A.|info:eu-repo/dai/nl/304848018; Hoorn, C.; van den Berg, B.C.J.; Guo, Z.; Dupont-Nivet, G.|info:eu-repo/dai/nl/313092559


    Global climate cooling from greenhouse to icehouse conditions occurred across an enigmatic transitional interval during the Eocene epoch characterized by incipient polar ice-sheet formation as well as short-lived warming events, of which the Middle Eocene Climatic Optimum (MECO) is most noticeable.

  3. Earliest record of the fossil snake Palaeophis from the Paleocene/Eocene boundary in Denmark

    DEFF Research Database (Denmark)

    Kristensen, Hans Viborg; Cuny, Gilles; Redsted Rasmussen, Arne


    Abstract. – The earliest record of Palaeophis ever found in Denmark is here based on vertebrae described from the Paleocene/Eocene Stolleklint Clay of the Isle of Mors (northern Denmark). Although much smaller, they appear quite similar to the Eocene vertebra described from the Fur Formation in t...

  4. Pronounced zonal heterogeneity in Eocene southern high-latitude sea surface temperatures

    NARCIS (Netherlands)

    Douglas, P.M.J.; Affek, H.P.; Ivany, L.C.; Houben, A.J.P.; Sijp, W.P.; Sluijs, A.; Schouten, S.; Pagani, M.


    Paleoclimate studies suggest that increased global warmth during the Eocene epoch was greatly amplified at high latitudes, a state that climate models cannot fully reproduce. However, proxy estimates of Eocene near-Antarctic sea surface temperatures (SSTs) have produced widely divergent results at

  5. Warm and wet conditions in the Arctic region during Eocene Thermal Maximum 2

    NARCIS (Netherlands)

    Sluijs, A.; Schouten, S.; Donders, T.H.; Schoon, P.L.; Röhl, U.; Reichart, G.-J.; Sangiorgi, F.; Kim, J.-H.; Sinninghe Damsté, J.S.; Brinkhuis, H.


    Several episodes of abrupt and transient warming, each lasting between 50,000 and 200,000 years, punctuated the long-term warming during the Late Palaeocene and Early Eocene (58 to 51 Myr ago) epochs1,2. These hyperthermal events, such as the Eocene Thermal Maximum 2 (EMT2) that took place about

  6. Paleoceanographic, and paleoclimatic constraints on the global Eocene diatom and silicoflagellate record (United States)

    Barron, John A.; Stickley, Catherine E.; Bukry, David


    Eocene diatom and silicoflagellate biostratigraphy are summarized and correlated with the most recent geologic time scale as well as with the global oxygen isotope and eustatic sea level curves. The global distribution of Eocene diatom/silicoflagellate-bearing sediments varies considerably, reflecting changing oceanic gateways and paleoceanography with changing patterns that are punctuated by four major depositional events.

  7. Diversity of Scydmaeninae (Coleoptera: Staphylinidae) in Upper Eocene Rovno amber. (United States)

    Jałoszyński, Paweł; Perkovsky, Evgeny


    Among nearly 1270 inclusions of Coleoptera found in Upper Eocene Rovno amber, 69 were identified as ant-like stone beetles (Scydmaeninae); 34 were possible to unambiguously determine to the tribal level and were studied in detail. Rovnoleptochromus ableptonoides gen. & sp. n. (Mastigitae: Clidicini), Vertheia quadrisetosa gen. & sp. n. (Cephenniitae: Eutheiini), Cephennomicrus giganteus sp. n. (Cephenniitae: Cephenniini), Glaesoconnus unicus gen. & sp. n. (Scydmaenitae: Glandulariini), Rovnoscydmus frontalis gen. & sp. n. (Scydmaenitae: Glandulariini; type species of Rovnoscydmus), Rovnoscydmus microscopicus sp. n., Euconnus (incertae sedis, near Cladoconnus) palaeogenus sp. n. (Scydmaenitae: Glandulariini), and Stenichnus (s. str.) proavus sp. n. (Scydmaenitae: Glandulariini) are described. Additionally, specimens representing one undescribed species of Vertheia, one of Cephennodes, five of Cephennomicrus, one of Euconnus, one of Microscydmus are recorded, and nine specimens representing an unknown number of species of Rovnoscydmus (and two putative Rovnoscydmus), one Euconnus (and one putative Euconnus), two putative Microscydmus and one putative Scydmoraphes were found in the studied material. The composition of Scydmaeninae fauna in Rovno amber is discussed in the context of ecological preferences and distribution of extant taxa. It is concluded that subtropical and tropical taxa were present in the region where Rovno amber has formed, most notably the second genus and species of the extant tribe Clidicini known from the Eocene of Europe, and six species of the extant genus Cephennomicrus, for the first time found in the fossil record. An annotated catalog of nominal species of Scydmaeninae known in the fossil record is given.

  8. Three-dimensional primate molar enamel thickness. (United States)

    Olejniczak, Anthony J; Tafforeau, Paul; Feeney, Robin N M; Martin, Lawrence B


    Molar enamel thickness has played an important role in the taxonomic, phylogenetic, and dietary assessments of fossil primate teeth for nearly 90 years. Despite the frequency with which enamel thickness is discussed in paleoanthropological discourse, methods used to attain information about enamel thickness are destructive and record information from only a single plane of section. Such semidestructive planar methods limit sample sizes and ignore dimensional data that may be culled from the entire length of a tooth. In light of recently developed techniques to investigate enamel thickness in 3D and the frequent use of enamel thickness in dietary and phylogenetic interpretations of living and fossil primates, the study presented here aims to produce and make available to other researchers a database of 3D enamel thickness measurements of primate molars (n=182 molars). The 3D enamel thickness measurements reported here generally agree with 2D studies. Hominoids show a broad range of relative enamel thicknesses, and cercopithecoids have relatively thicker enamel than ceboids, which in turn have relatively thicker enamel than strepsirrhine primates, on average. Past studies performed using 2D sections appear to have accurately diagnosed the 3D relative enamel thickness condition in great apes and humans: Gorilla has the relatively thinnest enamel, Pan has relatively thinner enamel than Pongo, and Homo has the relatively thickest enamel. Although the data set presented here has some taxonomic gaps, it may serve as a useful reference for researchers investigating enamel thickness in fossil taxa and studies of primate gnathic biology.

  9. Convergent evolution in primates and an insectivore

    Energy Technology Data Exchange (ETDEWEB)

    Boffelli, Dario; Cheng, Jan-Fang; Rubin, Edward M.


    The cardiovascular risk factor apolipoprotein(a) (apo(a)) has a puzzling distribution among mammals, its presence being limited to a subset of primates and a member of the insectivore lineage, the hedgehog. To explore the evolutionary history of apo(a), we performed extensive genomic sequence comparisons of multiple species with and without an apo(a) gene product, such as human, baboon, hedgehog, lemurand mouse. This analysis indicated that apo(a) arose independently in a subset of primates, including baboon and human, and an insectivore, the hedgehog, and was not simply lost by species lacking it. The similar structural domains shared by the hedgehog and primate apo(a) indicate that they were formed by a unique molecular mechanism involving the convergent evolution of paralogous genes in these distantspecies.

  10. First record of eocene bony fishes and crocodyliforms from Canada's Western Arctic.

    Directory of Open Access Journals (Sweden)

    Jaelyn J Eberle

    Full Text Available BACKGROUND: Discovery of Eocene non-marine vertebrates, including crocodylians, turtles, bony fishes, and mammals in Canada's High Arctic was a critical paleontological contribution of the last century because it indicated that this region of the Arctic had been mild, temperate, and ice-free during the early - middle Eocene (∼53-50 Ma, despite being well above the Arctic Circle. To date, these discoveries have been restricted to Canada's easternmost Arctic - Ellesmere and Axel Heiberg Islands (Nunavut. Although temporally correlative strata crop out over 1,000 km west, on Canada's westernmost Arctic Island - Banks Island, Northwest Territories - they have been interpreted as predominantly marine. We document the first Eocene bony fish and crocodyliform fossils from Banks Island. PRINCIPAL FINDINGS: We describe fossils of bony fishes, including lepisosteid (Atractosteus, esocid (pike, and amiid, and a crocodyliform, from lower - middle Eocene strata of the Cyclic Member, Eureka Sound Formation within Aulavik National Park (∼76°N. paleolat.. Palynology suggests the sediments are late early to middle Eocene in age, and likely spanned the Early Eocene Climatic Optimum (EECO. CONCLUSIONS/SIGNIFICANCE: These fossils extend the geographic range of Eocene Arctic lepisosteids, esocids, amiids, and crocodyliforms west by approximately 40° of longitude or ∼1100 km. The low diversity bony fish fauna, at least at the family level, is essentially identical on Ellesmere and Banks Islands, suggesting a pan-High Arctic bony fish fauna of relatively basal groups around the margin of the Eocene Arctic Ocean. From a paleoclimatic perspective, presence of a crocodyliform, gar and amiid fishes on northern Banks provides further evidence that mild, year-round temperatures extended across the Canadian Arctic during early - middle Eocene time. Additionally, the Banks Island crocodyliform is consistent with the phylogenetic hypothesis of a Paleogene divergence

  11. First record of eocene bony fishes and crocodyliforms from Canada's Western Arctic. (United States)

    Eberle, Jaelyn J; Gottfried, Michael D; Hutchison, J Howard; Brochu, Christopher A


    Discovery of Eocene non-marine vertebrates, including crocodylians, turtles, bony fishes, and mammals in Canada's High Arctic was a critical paleontological contribution of the last century because it indicated that this region of the Arctic had been mild, temperate, and ice-free during the early - middle Eocene (∼53-50 Ma), despite being well above the Arctic Circle. To date, these discoveries have been restricted to Canada's easternmost Arctic - Ellesmere and Axel Heiberg Islands (Nunavut). Although temporally correlative strata crop out over 1,000 km west, on Canada's westernmost Arctic Island - Banks Island, Northwest Territories - they have been interpreted as predominantly marine. We document the first Eocene bony fish and crocodyliform fossils from Banks Island. We describe fossils of bony fishes, including lepisosteid (Atractosteus), esocid (pike), and amiid, and a crocodyliform, from lower - middle Eocene strata of the Cyclic Member, Eureka Sound Formation within Aulavik National Park (∼76°N. paleolat.). Palynology suggests the sediments are late early to middle Eocene in age, and likely spanned the Early Eocene Climatic Optimum (EECO). These fossils extend the geographic range of Eocene Arctic lepisosteids, esocids, amiids, and crocodyliforms west by approximately 40° of longitude or ∼1100 km. The low diversity bony fish fauna, at least at the family level, is essentially identical on Ellesmere and Banks Islands, suggesting a pan-High Arctic bony fish fauna of relatively basal groups around the margin of the Eocene Arctic Ocean. From a paleoclimatic perspective, presence of a crocodyliform, gar and amiid fishes on northern Banks provides further evidence that mild, year-round temperatures extended across the Canadian Arctic during early - middle Eocene time. Additionally, the Banks Island crocodyliform is consistent with the phylogenetic hypothesis of a Paleogene divergence time between the two extant alligatorid lineages Alligator

  12. Recent advances in primate nutritional ecology. (United States)

    Righini, Nicoletta


    Nutritional ecology seeks to explain, in an ecological and evolutionary context, how individuals choose, acquire, and process food to satisfy their nutritional requirements. Historically, studies of primate feeding ecology have focused on characterizing diets in terms of the botanical composition of the plants consumed. Further, dietary studies have demonstrated how patch and food choice in relation to time spent foraging and feeding are influenced by the spatial and temporal distribution of resources and by social factors such as feeding competition, dominance, or partner preferences. From a nutritional perspective, several theories including energy and protein-to-fiber maximization, nutrient mixing, and toxin avoidance, have been proposed to explain the food choices of non-human primates. However, more recently, analytical frameworks such as nutritional geometry have been incorporated into primatology to explore, using a multivariate approach, the synergistic effects of multiple nutrients, secondary metabolites, and energy requirements on primate food choice. Dietary strategies associated with nutrient balancing highlight the tradeoffs that primates face in bypassing or selecting particular feeding sites and food items. In this Special Issue, the authors bring together a set of studies focusing on the nutritional ecology of a diverse set of primate taxa characterized by marked differences in dietary emphasis. The authors present, compare, and discuss the diversity of strategies used by primates in diet selection, and how species differences in ecology, physiology, anatomy, and phylogeny can affect patterns of nutrient choice and nutrient balancing. The use of a nutritionally explicit analytical framework is fundamental to identify the nutritional requirements of different individuals of a given species, and through its application, direct conservation efforts can be applied to regenerate and protect specific foods and food patches that offer the opportunity of a

  13. Learning about primates' learning, language, and cognition (United States)

    Rumbaugh, Duane M.


    Results are presented of many years of research on the methods of teaching primates the language and cognitive skills which were long considered to be unteachable to particular species of primates. It was found that chimpanzee subjects could not only learn a number of 'stock sentences' but to use them in variations and several combinations for the purpose of solving various problems. Apes placed in different rooms could be taught to communicate via computer, and collaborate with each other on doing specific tasks. Contrary to expectations, young rhesus monkeys proved to be able to learn as much as the chimpanzee species.

  14. Scaling of rotational inertia of primate mandibles. (United States)

    Ross, Callum F; Iriarte-Diaz, Jose; Platts, Ellen; Walsh, Treva; Heins, Liam; Gerstner, Geoffrey E; Taylor, Andrea B


    The relative importance of pendulum mechanics and muscle mechanics in chewing dynamics has implications for understanding the optimality criteria driving the evolution of primate feeding systems. The Spring Model (Ross et al., 2009b), which modeled the primate chewing system as a forced mass-spring system, predicted that chew cycle time would increase faster than was actually observed. We hypothesized that if mandibular momentum plays an important role in chewing dynamics, more accurate estimates of the rotational inertia of the mandible would improve the accuracy with which the Spring Model predicts the scaling of primate chew cycle period. However, if mass-related momentum effects are of negligible importance in the scaling of primate chew cycle period, this hypothesis would be falsified. We also predicted that greater "robusticity" of anthropoid mandibles compared with prosimians would be associated with higher moments of inertia. From computed tomography scans, we estimated the scaling of the moment of inertia (I j ) of the mandibles of thirty-one species of primates, including 22 anthropoid and nine prosimian species, separating I j into the moment about a transverse axis through the center of mass (I xx ) and the moment of the center of mass about plausible axes of rotation. We found that across primates I j increases with positive allometry relative to jaw length, primarily due to positive allometry of jaw mass and I xx , and that anthropoid mandibles have greater rotational inertia compared with prosimian mandibles of similar length. Positive allometry of I j of primate mandibles actually lowers the predictive ability of the Spring Model, suggesting that scaling of primate chew cycle period, and chewing dynamics in general, are more strongly influenced by factors other than scaling of inertial properties of the mandible, such as the dynamic properties of the jaw muscles and neural control. Differences in cycle period scaling between chewing and locomotion

  15. Disproportional representation of primates in the ecological literature. (United States)

    Heymann, Eckhard W; Zinner, Dietmar; Ganzhorn, Jörg U


    We address the question why papers dealing with the ecology of primates are so sparsely represented in the general ecological literature. A literature analyses based on entries in Web of Science and PrimateLit reveals that despite a large number of papers published on primates in general and on the ecology of primates, only a very small fraction of these papers is published in high-ranking international ecological journals. We discuss a number of potential reasons for the disproportion and highlight the problems associated with experimental research on wild primates and constraints on sample size as major issues.

  16. A late Eocene palynological record of climate change and Tibetan Plateau uplift (Xining Basin, China)

    NARCIS (Netherlands)

    Abels, H.A.; Xu, Y.; Utescher, T.; Dupont-Nivet, G.


    Climate models suggest that Asian paleoenvironments, monsoons and continental aridification were primarily governed by tectonic uplift and sea retreat since the Eocene with potential contribution of global climate changes. However, the cause and timing of these paleoenvironmental changes remain

  17. Tracing the Eocene-Oligocene transition: A case study from North Bohemia

    Czech Academy of Sciences Publication Activity Database

    Kvaček, Z.; Teodoridis, V.; Mach, K.; Přikryl, Tomáš; Dvořák, Z.


    Roč. 89, č. 1 (2014), s. 21-66 ISSN 1214-1119 Keywords : boundary * climate * Early Oligocene * fauna * flora * Late Eocene * vegetation Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.515, year: 2014

  18. Differing Eocene floral histories in southeastern North America and Western Europe: influence of paleogeography (United States)

    Frederiksen, N.O.


    Pollen data show that in southeastern North America, the Eocene angiosperm flora attained its maximum relative diversity some 8 m.y. after the late early Eocene to earliest middle Eocene to earliest middle Eocene climatic maximum. Increasing diversity resulted in part from the flora's position on a large continent which allowed easy migration. In western Europe, the floral diversity began decreasing even before the climatic maximum. Paleogeography played large roles in this diversity decrease. In western Europe, terrestrial floras were on islands and peninsulas in the sea, so that the floras underwent increasing isolation and partial local extermination. Temperate plants generally did not migrate to western Europe, because of a lack of nearby uplands, lack of northern terrestrial source areas for these plants, and presence of the Turgai Straights barrier. -from Authors

  19. Primate Innovation: Sex, Age and Social Rank

    NARCIS (Netherlands)

    Reader, S.M.; Laland, K.N.


    Analysis of an exhaustive survey of primate behavior collated from the published literature revealed significant variation in rates of innovation among individuals of different sex, age and social rank. We searched approximately 1,000 articles in four primatology journals, together with other

  20. Primacy and recency effects in nonhuman primates. (United States)

    Castro, C A; Larsen, T


    The reports of primacy and recency memory effects in nonhuman primates have been criticized because they have all used an initiating response. That is, the presentation of the to-be-remembered list of items was always contingent on a response being initiated by the nonhuman primate. It has been argued that this initiating response improves performance for early items in the list, resulting in the occurrence of the primacy effect, independent of any memory processing mechanism. This criticism was addressed in the present study by not using an initiating response prior to the presentation of the list. Nevertheless, both a primacy and a recency effect were observed in all 6 rhesus monkeys evaluated using a serial probe recognition task. Thus, the results are similar to those for humans, in that both primacy and recency effects can be obtained in nonhuman primates. A brief literature review is included, and it is proposed that the primacy and recency effects observed in humans, nonhuman primates, and infraprimates can be explained within the context of the configural-association theory.

  1. Homeostasis in primates in hyperacceleration fields (United States)

    Fuller, C. A.


    Various homeostatic responses of a nonhuman primate, the squirrel monkey (Saimiri sciureus) to acute changes in the acceleration environment were examined. When these animals were exposed to a hyperdynamic field the body temperature was consistently depressed and the animals showed behavioral indications of increased drowsiness. Further, time of day played a significant role in influencing these responses.

  2. Nonhuman primate models in translational regenerative medicine. (United States)

    Daadi, Marcel M; Barberi, Tiziano; Shi, Qiang; Lanford, Robert E


    Humans and nonhuman primates (NHPs) are similar in size, behavior, physiology, biochemistry, structure and function of organs, and complexity of the immune system. Research on NHPs generates complementary data that bridge translational research from small animal models to humans. NHP models of human disease offer unique opportunities to develop stem cell-based therapeutic interventions that directly address relevant and challenging translational aspects of cell transplantation therapy. These include the use of autologous induced pluripotent stem cell-derived cellular products, issues related to the immune response in autologous and allogeneic setting, pros and cons of delivery techniques in a clinical setting, as well as the safety and efficacy of candidate cell lines. The NHP model allows the assessment of complex physiological, biochemical, behavioral, and imaging end points, with direct relevance to human conditions. At the same time, the value of using primates in scientific research must be carefully evaluated and timed due to expense and the necessity for specialized equipment and highly trained personnel. Often it is more efficient and useful to perform initial proof-of-concept studies for new therapeutics in rodents and/or other species before the pivotal studies in NHPs that may eventually lead to first-in-human trials. In this report, we present how the Southwest National Primate Research Center, one of seven NIH-funded National Primate Research Centers, may help the global community in translating promising technologies to the clinical arena.

  3. First Record of Eocene Bony Fishes and Crocodyliforms from Canada’s Western Arctic


    Eberle, Jaelyn J.; Gottfried, Michael D.; Hutchison, J. Howard; Brochu, Christopher A.


    BACKGROUND: Discovery of Eocene non-marine vertebrates, including crocodylians, turtles, bony fishes, and mammals in Canada's High Arctic was a critical paleontological contribution of the last century because it indicated that this region of the Arctic had been mild, temperate, and ice-free during the early - middle Eocene (∼53-50 Ma), despite being well above the Arctic Circle. To date, these discoveries have been restricted to Canada's easternmost Arctic - Ellesmere and Axel Heiberg Island...

  4. Eocene Antarctic seasonality inferred from high-resolution stable isotope profiles of fossil bivalves and driftwood (United States)

    Judd, E. J.; Ivany, L. C.; Miklus, N. M.; Uveges, B. T.; Junium, C. K.


    The Eocene Epoch was a time of large-scale global climate change, experiencing both the warmest temperatures of the Cenozoic and the onset of southern hemisphere glaciation. The record of average global temperatures throughout this transition is reasonably well constrained, however considerably less is known about the accompanying changes in seasonality. Seasonally resolved temperature data provide a wealth of information not readily available from mean annual temperature data alone. These data are particularly important in the climatically sensitive high latitudes, as they can elucidate the means by which climate changes and the conditions necessary for the growth of ice sheets. Several recent studies, however, have suggested the potential for monsoonal precipitation regimes in the early-middle Eocene high latitudes, which complicates interpretation of seasonally resolved oxygen isotope records in shallow nearshore marine settings. Seasonal precipitation and runoff could create a brackish, isotopically depleted lens in these environments, depleting summertime δ18Ocarb and thereby inflating the inferred mean and range of isotope-derived temperatures. Here, we assess intra-annual variations in temperature in shallow nearshore Antarctic waters during the middle and late Eocene, inferred from high-resolution oxygen isotope profiles from accretionary bivalves of the La Meseta Formation, Seymour Island, Antarctica. To address concerns related to precipitation and runoff, we also subsample exceptionally preserved fossil driftwood from within the formation and use seasonal differences in δ13Corg values to estimate the ratio of summertime to wintertime precipitation. Late Eocene oxygen isotope profiles exhibit strongly attenuated seasonal amplitudes and more enriched mean annual values in comparison with data from the middle Eocene. Preliminary fossil wood data are not indicative of a strongly seasonal precipitation regime, implying that intra-annual variation in oxygen

  5. Occurrence and distribution of Indian primates (United States)

    Karanth, K.K.; Nichols, J.D.; Hines, J.E.


    Global and regional species conservation efforts are hindered by poor distribution data and range maps. Many Indian primates face extinction, but assessments of population status are hindered by lack of reliable distribution data. We estimated the current occurrence and distribution of 15 Indian primates by applying occupancy models to field data from a country-wide survey of local experts. We modeled species occurrence in relation to ecological and social covariates (protected areas, landscape characteristics, and human influences), which we believe are critical to determining species occurrence in India. We found evidence that protected areas positively influence occurrence of seven species and for some species are their only refuge. We found evergreen forests to be more critical for some primates along with temperate and deciduous forests. Elevation negatively influenced occurrence of three species. Lower human population density was positively associated with occurrence of five species, and higher cultural tolerance was positively associated with occurrence of three species. We find that 11 primates occupy less than 15% of the total land area of India. Vulnerable primates with restricted ranges are Golden langur, Arunachal macaque, Pig-tailed macaque, stump-tailed macaque, Phayre's leaf monkey, Nilgiri langur and Lion-tailed macaque. Only Hanuman langur and rhesus macaque are widely distributed. We find occupancy modeling to be useful in determining species ranges, and in agreement with current species ranking and IUCN status. In landscapes where monitoring efforts require optimizing cost, effort and time, we used ecological and social covariates to reliably estimate species occurrence and focus species conservation efforts. ?? Elsevier Ltd.

  6. Functional morphology of cercopithecoid primate metacarpals. (United States)

    Patel, Biren A


    The primate fossil record suggests that terrestriality was more common in the past than it is today, particularly among cercopithecoid primates. Whether or not a fossil primate habitually preferred terrestrial substrates has typically been inferred from its forelimb anatomy. Because extant large-bodied terrestrial cercopithecine monkeys utilize digitigrade hand postures during locomotion, being able to identify if a fossil primate habitually adopted digitigrade postures would be particularly revealing of terrestriality in this group. This paper examines the functional morphology of metacarpals in order to identify osteological correlates of digitigrade versus palmigrade hand postures. Linear measurements were obtained from 324 individuals belonging to digitigrade and palmigrade cercopithecoid species and comparisons were made between hand posture groups. Digitigrade taxa have shorter metacarpals, relative to both body mass and humerus length, than palmigrade taxa. Also, digitigrade taxa tend to have metacarpals with smaller dorsoventral diameters, relative to the product of body mass and metacarpal length, compared to palmigrade taxa. The size and shape of the metacarpal heads do not significantly differ between hand posture groups. Multivariate analyses suggest that metacarpal shape can only weakly discriminate between hand posture groups. In general, while there are some morphological differences in the metacarpals between hand posture groups, similarities also exist that are likely related to the fact that even digitigrade cercopithecoids can adopt palmigrade hand postures in different situations (e.g., terrestrial running, arboreal locomotion), and/or that the functional demands of different hand postures are not reflected in all aspects of metacarpal morphology. Therefore, the lack of identifiable adaptations for specific hand postures in extant cercopithecoids makes it difficult to determine a preference for specific habitats from fossil primate hand bones

  7. Development of the Philippine Mobile Belt in northern Luzon from Eocene to Pliocene (United States)

    Suzuki, Shigeyuki; Peña, Rolando E.; Tam, Tomas A.; Yumul, Graciano P.; Dimalanta, Carla B.; Usui, Mayumi; Ishida, Keisuke


    The origin of the Philippine Archipelago is characterized by the combination of the oceanic Philippine Mobile Belt (PMB) and the Palawan Continental Block (PCB). This paper is focused on the geologic evolution of the PMB in northern Luzon from Eocene to Pliocene. The study areas (northern Luzon) are situated in the central part of the PMB which is occupied by its typical components made up of a pre-Paleocene ophiolitic complex, Eocene successions, Eocene to Oligocene igneous complex and late Oligocene to Pliocene successions. Facies analysis of the middle Eocene and late Oligocene to early Pliocene successions was carried out to understand the depositional environment of their basins. Modal sandstone compositions, which reflect the basement geology of the source area, were analyzed. Major element geochemistry of sediments was considered to reconstruct the tectonic settings. The following brief history of the PMB is deduced. During the middle Eocene, the PMB was covered by mafic volcanic rocks and was a primitive island arc. In late Eocene to late Oligocene time, the intermediate igneous complex was added to the mafic PMB crust. By late Oligocene to early Miocene time, the PMB had evolved into a volcanic island arc setting. Contributions from alkalic rocks are detected from the rock fragments in the sandstones and chemical composition of the Zigzag Formation. During the middle Miocene to Pliocene, the tectonic setting of the PMB remained as a mafic volcanic island arc.

  8. An ailuravine rodent from the lower Eocene Cambay Formation at Vastan, western India, and its palaeobiogeographic implications

    Energy Technology Data Exchange (ETDEWEB)

    Rana, R.S.; Kumar, K.; Escarguel, G.; Sahni, A.; Rose, K.D.; Smith, T.; Singh, H.; Singh, L. [Wadia Institute of Himalayan Geology, Dehra Dun (India)


    A new ailuravine rodent, Meldimys musak sp. nov. (Mammalia: Rodentia, Ischyromyidae), is recorded from the lower Eocene lignites of western India. It is the oldest record of Rodentia from India. M. musak is more derived than the earliest Eocene ailuravine Euromys cardosoi from Portugal and more generalized than late early Eocene E. inexpectatus and Ailuravus michauxi from France. Its dental morphology closely corresponds to the middle early Eocene species M. louisi, which lived about 52 Ma in Western Europe. Meldimys was previously known only from Europe, and ailuravines were previously reported only from Europe and North America. Its occurrence in India allows the first direct correlation between the early Eocene land mammal horizons of Europe and India, and raises the possibility of a terrestrial faunal exchange between India and Eurasia close to the Palaeocene-Eocene transition.

  9. Taxonomy and conservation of Vietnam's primates: a review. (United States)

    Blair, Mary E; Sterling, Eleanor J; Hurley, Martha M


    Vietnam has the highest number of primate taxa overall (24-27) and the highest number of globally threatened primate taxa (minimum 20) in Mainland Southeast Asia. Conservation management of these species depends in part on resolving taxonomic uncertainties, which remain numerous among the Asian primates. Recent research on genetic, morphological, and acoustic diversity in Vietnam's primates has clarified some of these uncertainties, although a number of significant classification issues still remain. Herein, we summarize and compare the major current taxonomic classifications of Vietnam's primates, discuss recent advances in the context of these taxonomies, and suggest key areas for additional research to best inform conservation efforts in a region crucial to global primate diversity. Among the most important next steps for the conservation of Vietnam's primates is a new consensus list of Asian primates that resolves current differences between major taxonomies, incorporates recent research advances, and recognizes units of diversity at scales below the species-level, whether termed populations, morphs, or subspecies. Priority should be placed on recognizing distinct populations, regardless of the species concept in use, in order to foster the evolutionary processes necessary for primate populations to cope with inevitable environmental changes. The long-term conservation of Vietnam's primates depends not only on an accepted and accurate taxonomy but also on funding for on-the-ground conservation activities, including training, and the continued dedication and leadership of Vietnamese researchers and managers. © 2011 Wiley Periodicals, Inc.

  10. Seawater calcium isotope ratios across the Eocene-Oligocene transition (United States)

    Griffith, E.M.; Paytan, A.; Eisenhauer, A.; Bullen, T.D.; Thomas, E.


    During the Eocene-Oligocene transition (EOT, ca. 34 Ma), Earth's climate cooled significantly from a greenhouse to an icehouse climate, while the calcite (CaCO3) compensation depth (CCD) in the Pacific Ocean increased rapidly. Fluctuations in the CCD could result from various processes that create an imbalance between calcium (Ca) sources to, and sinks from, the ocean (e.g., weathering and CaCO3 deposition), with different effects on the isotopic composition of dissolved Ca in the oceans due to differences in the Ca isotopic composition of various inputs and outputs. We used Ca isotope ratios (??44/40Ca) of coeval pelagic marine barite and bulk carbonate to evaluate changes in the marine Ca cycle across the EOT. We show that the permanent deepening of the CCD was not accompanied by a pronounced change in seawater ??44/40Ca, whereas time intervals in the Neogene with smaller carbonate depositional changes are characterized by seawater ??44/40Ca shifts. This suggests that the response of seawater ??44/40Ca to changes in weathering fluxes and to imbalances in the oceanic alkalinity budget depends on the chemical composition of seawater. A minor and transient fluctuation in the Ca isotope ratio of bulk carbonate may reflect a change in isotopic fractionation associated with CaCO3 precipitation from seawater due to a combination of factors, including changes in temperature and/or in the assemblages of calcifying organisms. ?? 2011 Geological Society of America.

  11. A new Acartophthalmites Hennig from Eocene Baltic amber (Diptera, Acalyptratae

    Directory of Open Access Journals (Sweden)

    Ricardo Pérez-de la Fuente


    Full Text Available A new fossil fly species, Acartophthalmites willii sp. n. (Diptera: Acalyptratae: Opomyzoidea from Baltic amber (Eocene, 56−33.9 Ma, is described based on a male originally assigned by Hennig (1969 to A. tertiaria Hennig, 1965, who erroneously also referred to it in the same work as “A. electrica Hennig” (unavailable name. The new species, representing the third named species of the extinct genus with unclear familial relationships Acartophthalmites Hennig, 1965, is herein described and illustrated in detail, and its systematic implications and relationships are discussed. From the morphological standpoint, the new species represents an intermediate form between the two formerly described species within the genus, therefore expanding the character combination diversity in this lineage of acalyptrate flies. The genus Acartophthalmites is considered to be most closely related to Clusiidae and, therefore, it is herein tentatively classified within the superfamily Opomyzoidea. The current work takes part of an effort to review the Acartophthalmites diversity in order to gain knowledge on the morphological data from the specimens described within the genus and ultimately enable a reliable analysis of its phylogenetic relationships with other acalyptrates.

  12. A new brontothere from the Eocene of South China

    Directory of Open Access Journals (Sweden)

    Alexander Averianov


    Full Text Available The upper Eocene Youganwo Formation in Maoming Province, Guangdong Province, China, produced abundant remains of turtles and crocodiles, but mammalian remains are rare. The previously found mammals from Youganwo Formation include a nimravid carnivore and an amynodontid perissodactyl. Here we report on a new brontotheriid perissodactyl from the Youganwo Formation. Maobrontops paganus gen. et sp. nov. is described based on a maxillary fragment with P4 and M1–2 (SYSU-M-4. Maobrontops paganus gen. et sp. nov. is characterized by the combination of a simple P4 without a hypocone with derived molars having large molar fossae and large anterolingual cingular cusp. A parsimony implied weighting character analysis places Maobrontops gen. nov. in the clade Embolotheriita as a sister taxon to the terminal subclade containing Nasamplus, Protembolotherium, and Embolotherium. Maobrontops paganus gen. et sp. nov. is one of the largest Asian brontotheres. The brontotheriid fauna of South China is endemic and includes at least three valid taxa: Dianotitan from Brontotheriita and Pygmaetitan and Maobrontops gen. nov. from Embolotheriita.

  13. Nonhuman primate models of polycystic ovary syndrome (United States)

    Abbott, David H; Nicol, Lindsey E; Levine, Jon E; Xu, Ning; Goodarzi, Mark O; Dumesic, Daniel A


    With close genomic and phenotypic similarity to humans, nonhuman primate models provide comprehensive epigenetic mimics of polycystic ovary syndrome (PCOS), suggesting early life targeting for prevention. Fetal exposure to testosterone (T), of all nonhuman primate emulations, provides the closest PCOS-like phenotypes, with early-to-mid gestation T-exposed female rhesus monkeys exhibiting adult reproductive, endocrinological and metabolic dysfunctional traits that are co-pathologies of PCOS. Late gestational T exposure, while inducing adult ovarian hyperandrogenism and menstrual abnormalities, has less dysfunctional metabolic accompaniment. Fetal exposures to dihydrotestosterone (DHT) or diethylstilbestrol (DES) suggest androgenic and estrogenic aspects of fetal programming. Neonatal exposure to T produces no PCOS-like outcome, while continuous T treatment of juvenile females causes precocious weight gain and early menarche (high T), or high LH and weight gain (moderate T). Acute T exposure of adult females generates polyfollicular ovaries, while chronic T exposure induces subtle menstrual irregularities without metabolic dysfunction. PMID:23370180

  14. Evolution of the hepcidin gene in primates

    Directory of Open Access Journals (Sweden)

    Tossi Alessandro


    Full Text Available Abstract Background Hepcidin/LEAP-1 is an iron regulatory hormone originally identified as an antimicrobial peptide. As part of a systematic analysis of the evolution of host defense peptides in primates, we have sequenced the orthologous gene from 14 species of non-human primates. Results The sequence of the mature peptide is highly conserved amongst all the analyzed species, being identical to the human one in great apes and gibbons, with a single residue conservative variation in Old-World monkeys and with few substitutions in New-World monkeys. Conclusion Our analysis indicates that hepcidin's role as a regulatory hormone, which involves interaction with a conserved receptor (ferroportin, may result in conservation over most of its sequence, with the exception of the stretch between residues 15 and 18, which in New-World monkeys (as well as in other mammals shows a significant variation, possibly indicating that this structural region is involved in other functions.

  15. [Ecotourism disturbances to non-human primates]. (United States)

    Fan, Peng-Lai; Xiang, Zuo-Fu


    In tandem with economic growth and rising living conditions, ecotourism has increasingly gained popularity among the Chinese public. Non-human primates, as charismatic animals and the closest relatives of human beings, have shown a strong affinity in attracting the general public and raising money, and for that reason a variety of monkey parks, valleys, and islands are becoming increasingly popular in China. Though successful in raising a substantial sum of money for the managing agency of a nature reserve, there may be negative impacts on monkey groups used in ecotourism. Here, to establish effective guards for non-human primates involved in ecotourism, we present a review on tourism disturbance and summarize the negative impacts on behavioral patterns, reproduction, and health condition of animals.

  16. Nonhuman primate dermatology: a literature review (United States)

    Bernstein, Joseph A.; Didier, Peter J.


    In general, veterinary dermatologists do not have extensive clinical experience of nonhuman primate (NHP) dermatoses. The bulk of the published literature does not provide an organized evidence-based approach to the NHP dermatologic case. The veterinary dermatologist is left to extract information from both human and veterinary dermatology, an approach that can be problematic as it forces the clinician to make diagnostic and therapeutic decisions based on two very disparate bodies of literature. A more cohesive approach to NHP dermatology – without relying on assumptions that NHP pathology most commonly behaves similarly to other veterinary and human disease – is required. This review of the dermatology of NHP species includes discussions of primary dermatoses, as well as diseases where dermatologic signs represent a significant secondary component, provides a first step towards encouraging the veterinary community to study and report the dermatologic diseases of nonhuman primates. PMID:19490576

  17. Immune evasion strategies of the primate lentiviruses. (United States)

    Evans, D T; Desrosiers, R C


    Individuals infected with human immunodeficiency virus (HIV) and macaques infected with simian immunodeficiency virus (SIV) make vigorous virus-specific antibody and cellular immune responses. Despite these responses, virus replication continues at all stages of infection and ultimately leads to immunological collapse, onset of opportunistic infections and death of infected hosts. Thus, the strategies by which HIV and SIV evade antiviral immune surveillance are fundamental to understanding lentiviral pathogenesis and crucial for our ability to develop effective strategies. It has become increasingly clear that the primate lentiviruses have evolved multiple and complementary mechanisms to circumvent host immune responses. Here we review these mechanisms of immune evasion considering contributions from both human and non-human primate systems.

  18. Late Eocene stable isotope stratigraphy of North Atlantic IODP Site U1411: Orbitally paced climatic heartbeat at the close of the Eocene greenhouse (United States)

    Coxall, Helen; Bohaty, Steve; Wilson, Paul; Liebrand, Diederik; Nyberg, Anna; Holmström, Max


    Integrated Ocean Drilling Program (IODP) Expedition 342 drilled sediment drifts on the Newfoundland margin to recover high-resolution records of North Atlantic ocean-climate history and track the evolution of the modern climate system through the Late Cretaceous and Early Cenozoic. An early Paleogene deep-sea benthic stable isotope composite record from multiple Exp. 342 sites is currently in development and will provide a key reference section for investigations of Atlantic and global climate dynamics. This study presents initial results for the late Eocene slice of the composite from Site U1411, located at mid depth (˜2850m Eocene paleodepth) on the Southeast Newfoundland Ridge. Stable oxygen (δ18O) and carbon (δ13C) isotope ratios were measured on 640 samples hosting exceptionally well-preserved epifaunal benthic foraminifera obtained from the microfossil-rich uppermost Eocene clays at 4cm spacing. Sedimentation rates average 2-3 cm/kyr through the late Eocene, such that our sampling resolution is sufficient to capture the dominant Milankovitch frequencies. Late Eocene Site U1411 benthic δ18O values (1.4 to 0.5‰ VPDB) are comparable to the Pacific and elsewhere in the Atlantic at similar depths; however, δ13C is lower by ˜0.5 ‰ with values intermediate between those of the Southern Labrador Sea to the north (-1 to 0) and mid latitude/South Atlantic (0.5 to 1.5) to the south, suggesting poorly ventilated bottom waters in the late Eocene North Atlantic and limited production of North Atlantic deep water. Applying the initial shipboard magneto-biostratigraphic age framework, the Site U1411 benthic δ13C and δ18O records display clear cyclicity on orbital timescales. Spectral analysis of the raw unfiltered datasets identifies eccentricity (400 and 100 kyr), obliquity (40 kyr) and precession (˜20 kyr) signals imprinted on our time series, revealing distinct climatic heart beats in the late Eocene prior to the transition into the 'ice house'.

  19. Pervasive adaptive evolution in primate seminal proteins.

    Directory of Open Access Journals (Sweden)

    Nathaniel L Clark


    Full Text Available Seminal fluid proteins show striking effects on reproduction, involving manipulation of female behavior and physiology, mechanisms of sperm competition, and pathogen defense. Strong adaptive pressures are expected for such manifestations of sexual selection and host defense, but the extent of positive selection in seminal fluid proteins from divergent taxa is unknown. We identified adaptive evolution in primate seminal proteins using genomic resources in a tissue-specific study. We found extensive signatures of positive selection when comparing 161 human seminal fluid proteins and 2,858 prostate-expressed genes to those in chimpanzee. Seven of eight outstanding genes yielded statistically significant evidence of positive selection when analyzed in divergent primates. Functional clues were gained through divergent analysis, including several cases of species-specific loss of function in copulatory plug genes, and statistically significant spatial clustering of positively selected sites near the active site of kallikrein 2. This study reveals previously unidentified positive selection in seven primate seminal proteins, and when considered with findings in Drosophila, indicates that extensive positive selection is found in seminal fluid across divergent taxonomic groups.

  20. Pervasive Adaptive Evolution in Primate Seminal Proteins.

    Directory of Open Access Journals (Sweden)


    Full Text Available Seminal fluid proteins show striking effects on reproduction, involving manipulation of female behavior and physiology, mechanisms of sperm competition, and pathogen defense. Strong adaptive pressures are expected for such manifestations of sexual selection and host defense, but the extent of positive selection in seminal fluid proteins from divergent taxa is unknown. We identified adaptive evolution in primate seminal proteins using genomic resources in a tissue-specific study. We found extensive signatures of positive selection when comparing 161 human seminal fluid proteins and 2,858 prostate-expressed genes to those in chimpanzee. Seven of eight outstanding genes yielded statistically significant evidence of positive selection when analyzed in divergent primates. Functional clues were gained through divergent analysis, including several cases of species-specific loss of function in copulatory plug genes, and statistically significant spatial clustering of positively selected sites near the active site of kallikrein 2. This study reveals previously unidentified positive selection in seven primate seminal proteins, and when considered with findings in Drosophila, indicates that extensive positive selection is found in seminal fluid across divergent taxonomic groups.

  1. Dietary quality and encephalization in platyrrhine primates (United States)

    Allen, Kari L.; Kay, Richard F.


    The high energetic costs of building and maintaining large brains are thought to constrain encephalization. The ‘expensive-tissue hypothesis’ (ETH) proposes that primates (especially humans) overcame this constraint through reduction of another metabolically expensive tissue, the gastrointestinal tract. Small guts characterize animals specializing on easily digestible diets. Thus, the hypothesis may be tested via the relationship between brain size and diet quality. Platyrrhine primates present an interesting test case, as they are more variably encephalized than other extant primate clades (excluding Hominoidea). We find a high degree of phylogenetic signal in the data for diet quality, endocranial volume and body size. Controlling for phylogenetic effects, we find no significant correlation between relative diet quality and relative endocranial volume. Thus, diet quality fails to account for differences in platyrrhine encephalization. One taxon, in particular, Brachyteles, violates predictions made by ETH in having a large brain and low-quality diet. Dietary reconstructions of stem platyrrhines further indicate that a relatively high-quality diet was probably in place prior to increases in encephalization. Therefore, it is unlikely that a shift in diet quality was a primary constraint release for encephalization in platyrrhines and, by extrapolation, humans. PMID:21831898

  2. The ecology of primate material culture. (United States)

    Koops, Kathelijne; Visalberghi, Elisabetta; van Schaik, Carel P


    Tool use in extant primates may inform our understanding of the conditions that favoured the expansion of hominin technology and material culture. The 'method of exclusion' has, arguably, confirmed the presence of culture in wild animal populations by excluding ecological and genetic explanations for geographical variation in behaviour. However, this method neglects ecological influences on culture, which, ironically, may be critical for understanding technology and thus material culture. We review all the current evidence for the role of ecology in shaping material culture in three habitual tool-using non-human primates: chimpanzees, orangutans and capuchin monkeys. We show that environmental opportunity, rather than necessity, is the main driver. We argue that a better understanding of primate technology requires explicit investigation of the role of ecological conditions. We propose a model in which three sets of factors, namely environment, sociality and cognition, influence invention, transmission and retention of material culture. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  3. Perinatal asphyxia in a nonhuman primate model. (United States)

    Jacobson Misbe, Elizabeth N; Richards, Todd L; McPherson, Ronald J; Burbacher, Thomas M; Juul, Sandra E


    Perinatal asphyxia is a leading cause of brain injury in neonates, occurring in 2-4 per 1,000 live births, and there are limited treatment options. Because of their similarity to humans, nonhuman primates are ideal for performing preclinical tests of safety and efficacy for neurotherapeutic interventions. We previously developed a primate model of acute perinatal asphyxia using 12-15 min of umbilical cord occlusion. Continuing this research, we have increased cord occlusion time from 15 to 18 min and extended neurodevelopmental follow-up to 9 months. The purpose of this report is to evaluate the increase in morbidity associated with 18 min of asphyxia by comparing indices obtained from colony controls, nonasphyxiated controls and asphyxiated animals. Pigtail macaques were delivered by hysterotomy after 0, 15 or 18 min of cord occlusion, then resuscitated. Over the ensuing 9 months, for each biochemical and physiologic parameters, behavioral and developmental evaluations, and structural and spectroscopic MRI were recorded. At birth, all asphyxiated animals required resuscitation with positive pressure ventilation and exhibited biochemical and clinical characteristics diagnostic of hypoxic-ischemic encephalopathy, including metabolic acidosis and attenuated brain activity. Compared with controls, asphyxiated animals developed long-term physical and cognitive deficits. This preliminary report characterizes the acute and chronic consequences of perinatal asphyxia in a nonhuman primate model, and describes diagnostic imaging tools for quantifying correlates of neonatal brain injury as well as neurodevelopmental tests for evaluating early motor and cognitive outcomes. Copyright © 2011 S. Karger AG, Basel.

  4. Adaptive evolution of facial colour patterns in Neotropical primates


    Santana, Sharlene E.; Lynch Alfaro, Jessica; Alfaro, Michael E.


    The rich diversity of primate faces has interested naturalists for over a century. Researchers have long proposed that social behaviours have shaped the evolution of primate facial diversity. However, the primate face constitutes a unique structure where the diverse and potentially competing functions of communication, ecology and physiology intersect, and the major determinants of facial diversity remain poorly understood. Here, we provide the first evidence for an adaptive role of facial co...

  5. Fossil plant stomata indicate decreasing atmospheric CO2 prior to the Eocene-Oligocene boundary (United States)

    Steinthorsdottir, Margret; Porter, Amanda S.; Holohan, Aidan; Kunzmann, Lutz; Collinson, Margaret; McElwain, Jennifer C.


    A unique stratigraphic sequence of fossil leaves of Eotrigonobalanus furcinervis (extinct trees of the beech family, Fagaceae) from central Germany has been used to derive an atmospheric pCO2 record with multiple data points spanning the late middle to late Eocene, two sampling levels which may be earliest Oligocene, and two samples from later in the Oligocene. Using the inverse relationship between the density of stomata and pCO2, we show that pCO2 decreased continuously from the late middle to late Eocene, reaching a relatively stable low value before the end of the Eocene. Based on the subsequent records, pCO2 in parts of the Oligocene was similar to latest Eocene values. These results suggest that a decrease in pCO2 preceded the large shift in marine oxygen isotope records that characterizes the Eocene-Oligocene transition and that when a certain threshold of pCO2 change was crossed, the cumulative effects of this and other factors resulted in rapid temperature decline, ice build up on Antarctica and hence a change of climate mode.

  6. Biostratigraphy of a Paleocene–Eocene Foreland Basin boundary in southern Tibet

    Directory of Open Access Journals (Sweden)

    Xiaoqiao Wan


    Full Text Available This study of the Paleocene–Eocene boundary within a foreland basin of southern Tibet, which was dominated by a carbonate ramp depositional environment, documents more complex environmental conditions than can be derived from studies of the deep oceanic environment. Extinction rates for larger foraminiferal species in the Zongpu-1 Section apply to up to 46% of the larger foraminiferal taxa. The extinction rate in southern Tibet is similar to rates elsewhere in the world, but it shows that the Paleocene fauna disappeared stepwise through the Late Paleocene, with Eocene taxa appearing abruptly above the boundary. A foraminifera turnover was identified between Members 3 and 4 of the Zongpu Formation—from the Miscellanea–Daviesina assemblage to an Orbitolites–Alveolina assemblage. The Paleocene and Eocene boundary is between the SBZ 4 and SBZ 5, where it is marked by the extinction of Miscellanea miscella and the first appearance of Alveolina ellipsodalis and a large number of Orbitolites. Chemostratigraphically, the δ13C values from both the Zongpu-1 and Zongpu-2 Sections show three negative excursions in the transitional strata, one in Late Paleocene, one at the boundary, and one in the early Eocene. The second negative excursion of δ13C, which is located at the P–E boundary, coincides with larger foraminifera overturn. These faunal changes and the observed δ13C negative excursions provide new evidence on environmental changes across the Paleocene–Eocene boundary in Tibet.

  7. Why is a landscape perspective important in studies of primates? (United States)

    Arroyo-Rodríguez, Víctor; Fahrig, Lenore


    With accelerated deforestation and fragmentation through the tropics, assessing the impact that landscape spatial changes may have on biodiversity is paramount, as this information is required to design and implement effective management and conservation plans. Primates are expected to be particularly dependent on the landscape context; yet, our understanding on this topic is limited as the majority of primate studies are at the local scale, meaning that landscape-scale inferences are not possible. To encourage primatologists to assess the impact of landscape changes on primates, and help future studies on the topic, we describe the meaning of a "landscape perspective" and evaluate important assumptions of using such a methodological approach. We also summarize a number of important, but unanswered, questions that can be addressed using a landscape-scale study design. For example, it is still unclear if habitat loss has larger consistent negative effects on primates than habitat fragmentation per se. Furthermore, interaction effects between habitat area and other landscape effects (e.g., fragmentation) are unknown for primates. We also do not know if primates are affected by synergistic interactions among factors at the landscape scale (e.g., habitat loss and diseases, habitat loss and climate change, hunting, and land-use change), or whether landscape complexity (or landscape heterogeneity) is important for primate conservation. Testing for patterns in the responses of primates to landscape change will facilitate the development of new guidelines and principles for improving primate conservation. © 2014 Wiley Periodicals, Inc.

  8. The adaptive value of primate color vision for predator detection. (United States)

    Pessoa, Daniel Marques Almeida; Maia, Rafael; de Albuquerque Ajuz, Rafael Cavalcanti; De Moraes, Pedro Zurvaino Palmeira Melo Rosa; Spyrides, Maria Helena Constantino; Pessoa, Valdir Filgueiras


    The complex evolution of primate color vision has puzzled biologists for decades. Primates are the only eutherian mammals that evolved an enhanced capacity for discriminating colors in the green-red part of the spectrum (trichromatism). However, while Old World primates present three types of cone pigments and are routinely trichromatic, most New World primates exhibit a color vision polymorphism, characterized by the occurrence of trichromatic and dichromatic females and obligatory dichromatic males. Even though this has stimulated a prolific line of inquiry, the selective forces and relative benefits influencing color vision evolution in primates are still under debate, with current explanations focusing almost exclusively at the advantages in finding food and detecting socio-sexual signals. Here, we evaluate a previously untested possibility, the adaptive value of primate color vision for predator detection. By combining color vision modeling data on New World and Old World primates, as well as behavioral information from human subjects, we demonstrate that primates exhibiting better color discrimination (trichromats) excel those displaying poorer color visions (dichromats) at detecting carnivoran predators against the green foliage background. The distribution of color vision found in extant anthropoid primates agrees with our results, and may be explained by the advantages of trichromats and dichromats in detecting predators and insects, respectively. © 2014 Wiley Periodicals, Inc.

  9. Carbon sources during the Paleocene-Eocene Thermal Maximum (United States)

    Frieling, Joost; Peterse, Francien; Lunt, Daniel; Bohaty, Steven; Sinninghe Damste, Jaap; Reichart, Gert-Jan; Sluijs, Appy


    The Paleocene-Eocene Thermal Maximum (PETM; 56 Ma) was a period of rapid 4-5°C global warming and a global negative carbon isotope excursion (CIE) of 3-4.5‰, signaling the input of at least 1500 Gt of δ13C-depleted carbon into the ocean-atmosphere system. Carbon cycle modeling has indicated that the shape and magnitude of this CIE are generally explained by a large and rapid initial pulse, followed by 50 kyr of 13C-depleted carbon injection. Crucially, some of suggested carbon sources, e.g. submarine methane hydrates and permafrost thawing, may respond to warming and act as positive carbon cycle feedbacks on millennial timescales. Previous analyses showed that warming started prior to the CIE at some high and mid-latitude sites, but is still unknown whether this is a global signal and timing and magnitude of such a warming remain poorly constrained. We generated a new high-resolution TEX86 and δ13C record from Ocean Drilling Program Site 959 in the eastern tropical Atlantic and find that initial warming preceded the PETM CIE by 10 kyr. Moreover, cross-correlation functions on these new and published temperature-δ13C data imply that substantial (2-3 °C) warming lead 13C-depleted carbon injection by an average of 2-3 kyr globally. Finally, a data compilation shows that global burial fluxes of non-detrital Ba approximately tripled across all depths of the ocean studied, which on PETM time scales can only be explained by significant Ba addition to the oceans. Submarine hydrates are Ba-rich and require warming to dissociate. The simplest explanation for the temperature lead and Ba addition to the ocean is that methane hydrates dissociated as a response to initial warming and acted as a positive carbon cycle feedback during the PETM. The attribution of the CIE to a carbon cycle feedback naturally leads to the question what caused the early warming. The absence of a 13C change during the early warming implies a 13C-neutral CO2 source, such as volcanism, is the most


    Directory of Open Access Journals (Sweden)

    Predrag Miščević


    Full Text Available The Eocene flysh in the region of Split (Dalmatia, Croatia is char¬acterized by the presence of layers with different characteristics. It mainly includes thin-layered marls, clayey marls, calcareous marls, clastic lay¬ered limestones, calcarenites and breccias. Those parts that can be de¬scribed as the soft rocks or hard clays by the mechanical means, exposed to weathering reduce the durability within "an engineering time scale". The paper deals with the factors that influence the weathering process. The analyzed weathering is a combination of processes acting simulta¬neously. Most of these processes depend on the change of the water con¬tent, thus the weathering process mainly develops when a material is subjected to the wetting-drying process, On the base of these results form of degradation process is modeled. The weathering process can be main¬ly described as physical weathering combined with chemical weathering on the free surfaces and on the cracks walls. Erosion as a result of weath¬ering, is the dominant geomorphic process on analyzed flysch terrain. According to the analysis, as the most appropriate due to the characteris¬tics the tests are chosen as index properties. Some of these tests are modified in order to adapt them to the determined characteristics of ma¬terials from flysch layers. The correlations between the measured values are used as the basis for the classification proposal of the analyzed mate¬rial, according to its resistance to weathering processes. Roughly, three main groups of samples are recognizable: the first one with carbonate content more then 90% is not weathered at the engineers time scale; the second group with carbonate content from 75% to 90% include samples susceptible to weathering in engineers time scale; the third group with carbonate content less then 75% include samples in which the weather¬ing occurs immediately after the exposition to the weathering factors.

  11. Warm arctic continents during the Palaeocene Eocene thermal maximum (United States)

    Weijers, Johan W. H.; Schouten, Stefan; Sluijs, Appy; Brinkhuis, Henk; Sinninghe Damsté, Jaap S.


    The Palaeocene-Eocene Thermal Maximum (PETM; ˜55.5 Ma) is a geologically relatively brief episode of extreme warmth. Both deep and surface ocean temperatures increased by up to 5 °C in equatorial waters and up to 8 °C in mid and high latitude waters. From the continents, the annual mean air temperature response during the PETM is still largely unknown, mainly due to a lack of quantitative temperature proxies and sufficient suitable, continuous high resolution records. Recently, a new proxy for continental temperature reconstructions has been proposed, based on the distribution of membrane lipids of bacteria in present-day soils [ J.W.H. Weijers, S. Schouten, J.C. van den Donker, E.C. Hopmans, J.S. Sinninghe Damsté (2007) Environmental controls on bacterial tetraether membrane lipid distribution in soils, Geochimica et Cosmochimica Acta 71, 703-713] and shown to reconstruct annual mean air temperature. In this study we applied this new proxy in an attempt to reconstruct the air temperature in high latitude continental areas during the PETM by analysis of a marine sedimentary sequence obtained from the Lomonosov Ridge in the central Arctic Ocean (Integrated Ocean Drilling Program Expedition 302, Site 004, Hole A). The results indicate a warming of ˜8 °C above background values of ˜17 °C. This warming is coincident with a similar rise in sea surface temperatures documented earlier. Our results thus further confirm the warm conditions in the Arctic, and point to a strongly reduced latitudinal temperature gradient during the PETM.

  12. Lepidological review on the fish fauna of the Kučlín locality (Upper Eocene, Czech Republic)

    Czech Academy of Sciences Publication Activity Database

    Přikryl, Tomáš


    Roč. 67, 3/4 (2011), s. 149-156 ISSN 0036-5343 Institutional research plan: CEZ:AV0Z30130516 Keywords : fossil fish fauna * Osteichthyes * scales * morphology * Paleogene * Upper Eocene * Upper Eocene (Czech Republic) Subject RIV: DB - Geology ; Mineralogy

  13. Primate malarias: Diversity, distribution and insights for zoonotic Plasmodium

    Directory of Open Access Journals (Sweden)

    Christina Faust


    Full Text Available Protozoans within the genus Plasmodium are well-known as the causative agents of malaria in humans. Numerous Plasmodium species parasites also infect a wide range of non-human primate hosts in tropical and sub-tropical regions worldwide. Studying this diversity can provide critical insight into our understanding of human malarias, as several human malaria species are a result of host switches from non-human primates. Current spillover of a monkey malaria, Plasmodium knowlesi, in Southeast Asia highlights the permeability of species barriers in Plasmodium. Also recently, surveys of apes in Africa uncovered a previously undescribed diversity of Plasmodium in chimpanzees and gorillas. Therefore, we carried out a meta-analysis to quantify the global distribution, host range, and diversity of known non-human primate malaria species. We used published records of Plasmodium parasites found in non-human primates to estimate the total diversity of non-human primate malarias globally. We estimate that at least three undescribed primate malaria species exist in sampled primates, and many more likely exist in unstudied species. The diversity of malaria parasites is especially uncertain in regions of low sampling such as Madagascar, and taxonomic groups such as African Old World Monkeys and gibbons. Presence–absence data of malaria across primates enables us to highlight the close association of forested regions and non-human primate malarias. This distribution potentially reflects a long coevolution of primates, forest-adapted mosquitoes, and malaria parasites. The diversity and distribution of primate malaria are an essential prerequisite to understanding the mechanisms and circumstances that allow Plasmodium to jump species barriers, both in the evolution of malaria parasites and current cases of spillover into humans.

  14. Pronounced zonal heterogeneity in Eocene southern high-latitude sea surface temperatures. (United States)

    Douglas, Peter M J; Affek, Hagit P; Ivany, Linda C; Houben, Alexander J P; Sijp, Willem P; Sluijs, Appy; Schouten, Stefan; Pagani, Mark


    Paleoclimate studies suggest that increased global warmth during the Eocene epoch was greatly amplified at high latitudes, a state that climate models cannot fully reproduce. However, proxy estimates of Eocene near-Antarctic sea surface temperatures (SSTs) have produced widely divergent results at similar latitudes, with SSTs above 20 °C in the southwest Pacific contrasting with SSTs between 5 and 15 °C in the South Atlantic. Validation of this zonal temperature difference has been impeded by uncertainties inherent to the individual paleotemperature proxies applied at these sites. Here, we present multiproxy data from Seymour Island, near the Antarctic Peninsula, that provides well-constrained evidence for annual SSTs of 10-17 °C (1σ SD) during the middle and late Eocene. Comparison of the same paleotemperature proxy at Seymour Island and at the East Tasman Plateau indicate the presence of a large and consistent middle-to-late Eocene SST gradient of ∼7 °C between these two sites located at similar paleolatitudes. Intermediate-complexity climate model simulations suggest that enhanced oceanic heat transport in the South Pacific, driven by deep-water formation in the Ross Sea, was largely responsible for the observed SST gradient. These results indicate that very warm SSTs, in excess of 18 °C, did not extend uniformly across the Eocene southern high latitudes, and suggest that thermohaline circulation may partially control the distribution of high-latitude ocean temperatures in greenhouse climates. The pronounced zonal SST heterogeneity evident in the Eocene cautions against inferring past meridional temperature gradients using spatially limited data within given latitudinal bands.

  15. Large-amplitude variations in carbon cycling and terrestrial weathering during the latest Paleocene and earliest Eocene: The record at Mead Stream, New Zealand

    NARCIS (Netherlands)

    Slotnick, B.S.; Dickens, G.R.; Nicolo, M.J.; Hollis, C.J.; Crampton, J.S.; Zachos, J.C.; Sluijs, A.

    The late Paleocene to early Eocene was marked by major changes in Earth surface temperature and carbon cycling. This included at least two, and probably more, geologically brief (<200-k.yr.) intervals of extreme warming, the Paleocene-Eocene thermal maximum (PETM) and the Eocene thermal maximum-2

  16. An eocene hystricognathous rodent from Texas: its significance in interpretations of continental drift. (United States)

    Wood, A E


    The earliest known representative of the fundamentally South American and African hystricognathous rodents has recently been found in the middle or late Eocene of southwestern Texas; this discovery supports the postulate of a northern and independent origin for the two southern groups and increases the evidence against mid-Tertiary trans-Atlantic migration of these rodents at a time when the South Atlantic was narrower than it is at present. The fossil seems to be related to the North American Eocene family Sciuravidae.

  17. Pulses of middle Eocene to earliest Oligocene climatic deterioration in southern California and the Gulf Coast (United States)

    Frederiksen, N.O.


    A general deterioration of terrestrial climate took place during middle Eocene to earliest Oligocene time in southern California and in the Gulf Coast. Pollen data, calibrated by calcareous nannofossil ages, indicate four events of rapid floral and/or vegetational change among angiosperms during this time interval. The events can be correlated between the two regions even though these regions lay within different floristic provinces, and each event of angiosperm change is interpreted to indicate a pulse of rapid climatic shift. The most distinct of these events is the Middle Eocene Diversity Decline, which resulted from a peak in last appearances (extinctions, emigrations) centered in the early Bartonian. -from Author

  18. Cellular Scaling Rules for Primate Spinal Cords


    Burish, Mark J.; Peebles, J. Klint; Baldwin, Mary K.; Tavares, Luciano; Kaas, Jon H.; Herculano-Houzel, Suzana


    The spinal cord can be considered a major sensorimotor interface between the body and the brain. How does the spinal cord scale with body and brain mass, and how are its numbers of neurons related to the number of neurons in the brain across species of different body and brain sizes? Here we determine the cellular composition of the spinal cord in eight primate species and find that its number of neurons varies as a linear function of cord length, and accompanies body mass raised to an expone...

  19. Two Influential Primate Classifications Logically Aligned. (United States)

    Franz, Nico M; Pier, Naomi M; Reeder, Deeann M; Chen, Mingmin; Yu, Shizhuo; Kianmajd, Parisa; Bowers, Shawn; Ludäscher, Bertram


    Classifications and phylogenies of perceived natural entities change in the light of new evidence. Taxonomic changes, translated into Code-compliant names, frequently lead to name:meaning dissociations across succeeding treatments. Classification standards such as the Mammal Species of the World (MSW) may experience significant levels of taxonomic change from one edition to the next, with potential costs to long-term, large-scale information integration. This circumstance challenges the biodiversity and phylogenetic data communities to express taxonomic congruence and incongruence in ways that both humans and machines can process, that is, to logically represent taxonomic alignments across multiple classifications. We demonstrate that such alignments are feasible for two classifications of primates corresponding to the second and third MSW editions. Our approach has three main components: (i) use of taxonomic concept labels, that is name sec. author (where sec. means according to), to assemble each concept hierarchy separately via parent/child relationships; (ii) articulation of select concepts across the two hierarchies with user-provided Region Connection Calculus (RCC-5) relationships; and (iii) the use of an Answer Set Programming toolkit to infer and visualize logically consistent alignments of these input constraints. Our use case entails the Primates sec. Groves (1993; MSW2-317 taxonomic concepts; 233 at the species level) and Primates sec. Groves (2005; MSW3-483 taxonomic concepts; 376 at the species level). Using 402 RCC-5 input articulations, the reasoning process yields a single, consistent alignment and 153,111 Maximally Informative Relations that constitute a comprehensive meaning resolution map for every concept pair in the Primates sec. MSW2/MSW3. The complete alignment, and various partitions thereof, facilitate quantitative analyses of name:meaning dissociation, revealing that nearly one in three taxonomic names are not reliable across treatments

  20. Primates, Provisioning and Plants: Impacts of Human Cultural Behaviours on Primate Ecological Functions.

    Directory of Open Access Journals (Sweden)

    Asmita Sengupta

    Full Text Available Human provisioning of wildlife with food is a widespread global practice that occurs in multiple socio-cultural circumstances. Provisioning may indirectly alter ecosystem functioning through changes in the eco-ethology of animals, but few studies have quantified this aspect. Provisioning of primates by humans is known to impact their activity budgets, diets and ranging patterns. Primates are also keystone species in tropical forests through their role as seed dispersers; yet there is no information on how provisioning might affect primate ecological functions. The rhesus macaque is a major human-commensal species but is also an important seed disperser in the wild. In this study, we investigated the potential impacts of provisioning on the role of rhesus macaques as seed dispersers in the Buxa Tiger Reserve, India. We studied a troop of macaques which were provisioned for a part of the year and were dependent on natural resources for the rest. We observed feeding behaviour, seed handling techniques and ranging patterns of the macaques and monitored availability of wild fruits. Irrespective of fruit availability, frugivory and seed dispersal activities decreased when the macaques were provisioned. Provisioned macaques also had shortened daily ranges implying shorter dispersal distances. Finally, during provisioning periods, seeds were deposited on tarmac roads that were unconducive for germination. Provisioning promotes human-primate conflict, as commensal primates are often involved in aggressive encounters with humans over resources, leading to negative consequences for both parties involved. Preventing or curbing provisioning is not an easy task as feeding wild animals is a socio-cultural tradition across much of South and South-East Asia, including India. We recommend the initiation of literacy programmes that educate lay citizens about the ill-effects of provisioning and strongly caution them against the practice.

  1. Multimedia in Anthropology: A Guide to the Nonhuman Primates. (United States)

    Burton, Frances D.

    This paper describes a primatology project using computer assisted learning and interactive multimedia to help students at the University of Toronto (Canada) learn about non-human primates. The purpose of the interactive program is to present the "natural history" of the majority of the 200-plus species of non-human primates in constant…

  2. A brief history of primate research: Global health improvements and ...

    African Journals Online (AJOL)

    Scientists rapidly realized the value of primates as research models – their evolutionary proximity to humans making them better predictors, or models, of human biology. Systematic studies using primates began in the last century and massive demand for research subjects almost caused the extinction of some important ...

  3. Ancient Fungal Life in North Pacific Eocene Oceanic Crust (United States)

    Schumann, G.; Manz, W.; Reitner, J.; Lustrino, M.


    Little is known about the manifold life forms of the deep biosphere although there is increasing scientific evidence that an extensive biosphere does exist in extreme environments such as the rocks below the seafloor. The ODP Leg 200 was devoted to the study of Eocene oceanic crust of the North Pacific Ocean. Within a massive tholeiitic lava flow unit, at depth of 51 mbsf underneath a water column of about 5000 m, we found unique filamentous structures. Based on morphological traits like branching, septa and central pores the filaments are interpreted as fungi. These filaments were found within carbonate-filled vesicles ranging in size from 0.5 to 3 mm in diameter. The net of fungal hyphae completely fills the whole pore space from the basalt-carbonate boundary towards the center of the pores. The cross section dimension of these filaments is about 5-10 micrometer and the length differ from 50 to several hundreds micrometer. Thereby the cell septa of the hyphae are clearly visible. The number of hyphae ranges from some tenth to some hundreds per particular pore. The presence of pyrite within the carbonate cements points out anaerobic conditions in this habitat. After removing the carbonate by etching the vesicles with diluted formic acid, the 3-dimensional structure of the fungus could be clearly visualized. Fine structure analysis of the hyphae obtained by field emission scanning electron microscopy (FE-SEM) revealed a network of tiny small fibers coating the surface of the hyphae. Semi-quantitative chemical analyses of the etched hyphae were conducted with an energy dispersive spectrometer system (EDS) coupled with the FE-SEM. The results evidence a chemical composition of the hyphae different from the surrounding carbonate matrix. Undisturbed filamentous growth through different calcite crystals within the vesicles and small open space between the fungi and matrix indicate endolithic fungal growth after the calcium carbonate filling of the vesicles. To the best

  4. Primate theory of mind: a state of the art review

    DEFF Research Database (Denmark)

    Byrnit, Jill


    Såvel mennesket som andre primater have store hjerner med store hjernebarker. Det er blevet foreslået, at primaters store hjerner skyldes de komplekse sociale krav, der kommer af at skulle leve i store grupper. Inden for de sidste 40 år er der blevet lavet meget forskning inden for primaters socio-cognitive...... evner og siden Premack & Woodruff (1978) for første gang introducerede begrebet "theory of mind", er der blevet foretaget mange laboratorie-forsøg om mennesker og andre primaters evne til at attribuere mentale tilstande til andre. I nærværende artikel er størstedelen af disse forsøg med andre primater...

  5. Predicting primate responses to "Stochastic" demographic events. (United States)

    Strier, K B


    Comparative approaches in contemporary primate behavioral ecology have tended to emphasize the deterministic properties of stochastic ecological variables. Yet, primate responses to ecological fluctuations may be mediated by the interactions among demographic processes at the levels of individuals, groups, and populations. In this paper I examine long-term data collected from June 1982-July 1998 on one expanding group of muriquis (Brachyteles arachnoides) at the Estação Biologica de Caratinga, Minas Gerais, Brazil to explore the demographic and life history correlates of reproductive seasonality and skewed infant sex ratios. Variation in the size of annual birth cohorts (≥2 infants) was positively related to variation in the annual distribution of births (r (s)=0.96,n=10,p<0.01), indicating the importance of considering the effects that the number of reproductive females may have on interpretations of reproductive seasonality. The female-biased infants sex ratio documented from 59 births was attributed exclusively to multiparous mothers. Primiparous mothers produced comparable numbers of sons (n=6) and daughters (n=7), and were increasingly likely to produce daughters with each subsequent reproductive event. Seven of the 11 females that have produced≥3 infants to date exhibited biases in favor of daughters whereas only 1 was biased in favor of sons. Variation in female sensitivity to local resource competition at different stages of their life histories may account for the female-biased infant sex ration in this population.

  6. Primate pelvic anatomy and implications for birth. (United States)

    Trevathan, Wenda


    The pelvis performs two major functions for terrestrial mammals. It provides somewhat rigid support for muscles engaged in locomotion and, for females, it serves as the birth canal. The result for many species, and especially for encephalized primates, is an 'obstetric dilemma' whereby the neonate often has to negotiate a tight squeeze in order to be born. On top of what was probably a baseline of challenging birth, locomotor changes in the evolution of bipedalism in the human lineage resulted in an even more complex birth process. Negotiation of the bipedal pelvis requires a series of rotations, the end of which has the infant emerging from the birth canal facing the opposite direction from the mother. This pattern, strikingly different from what is typically seen in monkeys and apes, places a premium on having assistance at delivery. Recently reported observations of births in monkeys and apes are used to compare the process in human and non-human primates, highlighting similarities and differences. These include presentation (face, occiput anterior or posterior), internal and external rotation, use of the hands by mothers and infants, reliance on assistance, and the developmental state of the neonate. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  7. The role of piloerection in primate thermoregulation. (United States)

    Chaplin, George; Jablonski, Nina G; Sussman, Robert W; Kelley, Elizabeth A


    The insulating properties of the primate integument are influenced by many factors, including piloerection, which raises the hair and insulates the body by creating motionless air near the skin's surface. The involuntary muscles that control piloerection, the musculi arrectores pilorum (MAP), are mostly absent except on the tail in most strepsirhines, and are entirely absent in tarsiers and some lorisids. The absence of piloerection and the reduced effectiveness of pilary insulation in preventing heat loss affected the evolution of behavior and metabolic thermoregulation in these animals. In lemurs, this situation contributed to the use of positional and social behaviors such as sunning and huddling that help maintain thermal homeostasis during day-night and seasonal temperature cycles. It also contributed in many lemurs and lorises to the evolution of a wide variety of activity patterns and energy-conserving metabolic patterns such as cathemerality, daily torpor, and hibernation. The absence of functional MAP in strepsirhines and tarsiers implies the absence of effective piloerection in early primates, and the reacquisition of whole-body MAP in ancestral anthropoids prior to the separation of platyrrhine and catarrhine lineages. © 2013 S. Karger AG, Basel.

  8. Primate pelvic anatomy and implications for birth (United States)

    Trevathan, Wenda


    The pelvis performs two major functions for terrestrial mammals. It provides somewhat rigid support for muscles engaged in locomotion and, for females, it serves as the birth canal. The result for many species, and especially for encephalized primates, is an ‘obstetric dilemma’ whereby the neonate often has to negotiate a tight squeeze in order to be born. On top of what was probably a baseline of challenging birth, locomotor changes in the evolution of bipedalism in the human lineage resulted in an even more complex birth process. Negotiation of the bipedal pelvis requires a series of rotations, the end of which has the infant emerging from the birth canal facing the opposite direction from the mother. This pattern, strikingly different from what is typically seen in monkeys and apes, places a premium on having assistance at delivery. Recently reported observations of births in monkeys and apes are used to compare the process in human and non-human primates, highlighting similarities and differences. These include presentation (face, occiput anterior or posterior), internal and external rotation, use of the hands by mothers and infants, reliance on assistance, and the developmental state of the neonate. PMID:25602069

  9. Postradiation regional cerebral blood flow in primates

    International Nuclear Information System (INIS)

    Cockerham, L.G.; Cerveny, T.J.; Hampton, J.D.


    Early transient incapacitation (ETI) is the complete cessation of performance during the first 30 min after radiation exposure and performance decrement (PD) is a reduction in performance at the same time. Supralethal doses of radiation have been shown to produce a marked decrease in regional cerebral blood flow in primates concurrent with hypotension and a dramatic release of mast cell histamine. In an attempt to elucidate mechanisms underlying the radiation-induced ETI/PD phenomenon and the postradiation decrease in cerebral blood flow, primates were exposed to 100 Gy (1 Gy = 100 rads), whole-body, gamma radiation. Pontine and cortical blood flows were measured by hydrogen clearance, before and after radiation exposure. Systemic blood pressures were determined simultaneously. Systemic arterial histamine levels were determined preradiation and postradiation. Data obtained indicated that radiated animals showed a decrease in blood flow of 63% in the motor cortex and 51% in the pons by 10 min postradiation. Regional cerebral blood flow of radiated animals showed a slight recovery 20 min postradiation, followed by a fall to the 10 min nadir by 60 min postradiation. Immediately, postradiation systemic blood pressure fell 67% and remained at that level for the remainder of the experiment. Histamine levels in the radiated animals increased a hundredfold 2 min postradiation. This study indicates that regional cerebral blood flow decreases postradiation with the development of hypotension and may be associated temporally with the postradiation release of histamine

  10. Identification of the Paleocene-Eocene boundary in coastal strata in the Otway Basin, Victoria, Australia

    NARCIS (Netherlands)

    Frieling, J.|info:eu-repo/dai/nl/338017909; Huurdeman, Emiel; Rem, Charlotte; Donders, T.H.|info:eu-repo/dai/nl/290469872; Pross, Jorg; Bohaty, Steven M.; Holdgate, Guy; Gallagher, Stephen; McGowran, Brian; Bijl, P.K.|info:eu-repo/dai/nl/314028110


    Detailed, stratigraphically well-constrained environmental reconstructions are available for Paleocene and Eocene strata at a range of sites in the southwest Pacific Ocean (New Zealand and East Tasman Plateau; ETP) and Integrated Ocean Discovery Program (IODP) Site U1356 in the south of the

  11. Justitia Holthuis, 1946 (Crustacea, Decapoda, Palinuridea) from the Middle Eocene of Verona and Vicenza (northern Italy)

    NARCIS (Netherlands)

    Garassino, Alessandro; Angeli, De Antonio


    Recently, Beschin et al. (2001) have described two specimens of palinurids, discovered at Chiampo (“Albanello” quarry, Vicenza, northern Italy). Preserved three dimensionally, these were collected from limestones of Lutetian (middle Eocene) age. The peculiar ornament of the dorsal carapace surface,

  12. Synchronizing terrestrial and marine records of environmental change across the Eocene-Oligocene transition

    NARCIS (Netherlands)

    Sahy, D.; Condon, D.J.; Terry, D.O., Jr.; Fischer, A.U.; Kuiper, K.F.


    Records of terrestrial environmental change indicate that continental cooling and/or aridification may have predated the greenhouse-icehouse climate shift at the Eocene-Oligocene transition (EOT) by ca. 600 kyr. In North America, marine-terrestrial environmental change asynchronicity is inferred

  13. Eocene relatives of cod icefishes (Perciformes: Notothenioidei) from Seymour Island, Antarctica

    DEFF Research Database (Denmark)

    Bieńkowska-Wasiluk, Małgorzata; Bonde, Niels Christensøn; Møller, Peter Rask


    to the perciform suborder Notothenioidei. This group is almost unknown as fossils. Similarities to the living, ‘primitive’ nototheniid Dissostichus eleginoides are indicated in the dentition. Gadiform evolution in the Paleocene-Eocene, and the possibility of a correlation between the origin and evolution...

  14. Some new Eocene elasmobranch reports from the outer Western Carpathians (Moravia, Czech Republic)

    Czech Academy of Sciences Publication Activity Database

    Přikryl, Tomáš; Skupien, P.


    Roč. 268, č. 1 (2013), s. 113-123 ISSN 0077-7749 Institutional research plan: CEZ:AV0Z30130516 Institutional support: RVO:67985831 Keywords : Elasmobranchii * Leidybatis jugossus * Centrophorus * Eocene * Western Carpathian Subject RIV: DB - Geology ; Mineralogy Impact factor: 0.541, year: 2013

  15. Palaeoceanographic and biotic response during early Eocene extreme global warming events. Geologica Ultraiectina (328)

    NARCIS (Netherlands)

    Stap, H.L.


    Studying past intervals of abrupt global warming and massive carbon release can improve our knowledge in ways relevant to understanding future climate change. Possible paleo-analogues for future climate change are the early Paleogene hyperthermal events, such as the Paleocene-Eocene Thermal Maximum

  16. Terrestrial Palynology of Paleocene and Eocene Sediments Above the Chicxulub Impact Crater (United States)

    Smith, V.; Warny, S.; Bralower, T. J.; Jones, H.; Lowery, C. M.; Smit, J.; Vajda, V.; Vellekoop, J.; 364 Scientists, E.


    International Ocean Discovery Program (IODP) Expedition 364, with support from the International Continental Scientific Drilling Program, cored through Paleocene and Eocene sediments and into the impact structure of the Chicxulub impact crater. Three palynological studies of the post-impact section are currently underway. The two other studies are investigating the dinoflagellate palynology and terrestrial palynology of the K/Pg boundary section, while this study focuses on the early Eocene terrestrial palynology of the IODP 364 core, which has yielded a diverse and well preserved pollen assemblage. A few samples from the Early Paleocene have also been examined but organic microfossil preservation is quite poor. Samples from this core are the oldest palynological record from the Yucatan peninsula. Sample preparation and detailed abundance counts of sixty samples throughout the post-impact section are in progress, with a particular focus on the Paleocene-Eocene Thermal Maximum (PETM) and the Early Eocene Climatic Optimum (EECO). Terrestrial palynomorph assemblages will be used to reconstruct paleoclimatological conditions throughout this time period. Floral response to hyperthermal events in the IODP 364 core will be compared with records from other Gulf of Mexico and Caribbean sections. In addition to the biological and paleoclimatological implications of this research, age control from foraminiferal and nannofossil biostratigraphy, paleomagnetism, and radiometric dating will provide a chronological framework for the terrestrial pollen biostratigraphy, with applications to hydrocarbon exploration in the Wilcox Formation and age equivalent sections in the Gulf of Mexico.

  17. Salinity of the Eocene Arctic Ocean from oxygen isotope analysis of fish bone carbonate (United States)

    Waddell, Lindsey M.; Moore, Theodore C.


    Stable isotope analysis was performed on the structural carbonate of fish bone apatite from early and early middle Eocene samples (˜55 to ˜45 Ma) recently recovered from the Lomonosov Ridge by Integrated Ocean Drilling Program Expedition 302 (the Arctic Coring Expedition). The δ18O values of the Eocene samples ranged from -6.84‰ to -2.96‰ Vienna Peedee belemnite, with a mean value of -4.89‰, compared to 2.77‰ for a Miocene sample in the overlying section. An average salinity of 21 to 25‰ was calculated for the Eocene Arctic, compared to 35‰ for the Miocene, with lower salinities during the Paleocene Eocene thermal maximum, the Azolla event at ˜48.7 Ma, and a third previously unidentified event at ˜47.6 Ma. At the Azolla event, where the organic carbon content of the sediment reaches a maximum, a positive δ13C excursion was observed, indicating unusually high productivity in the surface waters.

  18. Eocene rotation of Sardinia, and the paleogeography of the western Mediterranean region

    NARCIS (Netherlands)

    Advokaat, Eldert; van Hinsbergen, D.J.J.|info:eu-repo/dai/nl/269263624; Maffione, M.; Langereis, C.G.|info:eu-repo/dai/nl/073584223; Vissers, R.L.M.|info:eu-repo/dai/nl/068789203; Cherchi, A.; Schroeder, R.; Madani, H.; Columbu, S.


    Key to understanding the complex Mediterranean subduction history is the kinematic reconstruction of its paleogeography after Jurassic extension between Iberia, Eurasia, and Africa. While post-Eocene Liguro-Provençal back-arc extension, and associated Miocene ~50° counterclockwise (ccw) rotation of

  19. Early-middle Eocene birds from the Lillebaelt Clay Formation of Denmark

    DEFF Research Database (Denmark)

    Lindow, Bent Erik Kramer


    The marine Lillebaelt Clay Formation of central Denmark is of early-middle Eocene age (late Ypresian - middle Lutetian; microfossil zones NP 13-NP 15). Over 20 bird fossils collected by amateur palaeontologists have been acquired through the Danish national ‘Danekrae' fossil treasure trove...

  20. Astrochronology of extreme global warming events during the early Eocene greenhouse climate

    NARCIS (Netherlands)

    Lauretano, V.


    The early Eocene represents an ideal case study to analyse the impact of enhanced global warming on the ocean-atmosphere system and the relationship between carbon cycling and climate. During this time interval, the Earth’s surface experienced a long-term warming trend that culminated in a period of

  1. Palaeoecological and palaeoclimatological implications of the Eocene Northern Hemisphere Azolla phenomenon

    NARCIS (Netherlands)

    Barke, J.


    The high abundances and cyclic distribution of remains of the freshwater fern Azolla in early middle Eocene sediments from the Arctic Ocean have previously been related to episodic surface water freshening, which was speculated to be orbitally modulated. Our integrated palynological and

  2. Diatom and silicoflagellate biostratigraphy for the late Eocene: ODP 1090 (sub-Antarctic Atlantic) (United States)

    Barron, John A.; Bukry, David B.; Gersonde, Rainer


    Abundant and well-preserved diatoms and silicofl agellate assemblages are documented through a complete late Eocene sequence, ODP Hole 1090B, recovered from the southern Agulhas Ridge in the sub-Antarctic South Atlantic. A sequence of Cestodiscus (diatom) species occurrence events involving C. pulchellus var. novazealandica, C. fennerae, C. antarcticus, C. convexus, C. trochus, and C. robustus is tied with paleomagnetic stratigraphy and provides the basis of proposing a new diatom zonation for the latest middle Eocene to early Oligocene (~37.6–33.4 Ma) of the sub-Antarctic South Atlantic. Comparison with previously published diatom occurrence charts suggested this zonation should be applicable throughout the low latitude regions of the world’s oceans. Silicofl agellates belong to the Dictyocha hexacantha and the overlying Corbisema apiculata Zones. The late Eocene succession of silicofl agellate species is dominated by Naviculopsis (20–60%). Naviculopsis constricta and N. foliacea dominate the D. hexacantha Zone, followed by the N. constricta, then N. biapiculata in the C. apiculata Zone. Cold-water Distephanus is most abundant in the latest Eocene along with N. biapiculata. The tops of zonal guide fossils Dictyocha hexacantha and Hannaites quadria (both 36.6 Ma) and Dictyocha spinosa (37.1 Ma) are tied with paleomagnetic stratigraphy.

  3. Climate, carbon cycling and marine ecology during the Paleocene-Eocene Thermal Maximum

    NARCIS (Netherlands)

    Frieling, J.


    The Paleocene and Eocene are characterized by strong greenhouse climates. Atmospheric CO2 concentrations and global temperatures were much higher than today. The period from 60 to 50 million years ago (Ma) is marked by a gradual warming trend of ~8 ºC in the deep ocean. The interval from 56 to 50 Ma

  4. Frequency, magnitude and character of hyperthermal events at the onset of the Early Eocene Climatic Optimum

    NARCIS (Netherlands)

    Lauretano, V.; Littler, K.; Polling, M.; Zachos, J.C.; Lourens, L.J.


    Recent studies have shown that the Early Eocene Climatic Optimum (EECO) was preceded by a series of short-lived global warming events, known as hyperthermals. Here we present high-resolution benthic stable carbon and oxygen isotope records from ODP Sites 1262 and 1263 (Walvis Ridge, SE Atlantic)

  5. Triggers and consequences of glacial expansion across the Eocene - Oligocene Transition

    NARCIS (Netherlands)

    Houben, A.J.P.


    The results described in this thesis provide a rather complex picture of climatic, environmental and biotic changes preceding and arising from the onset of Antarctic glaciation. This period is commonly known as the greenhouse to icehouse transition across the Eocene-Oligocene Transition (EOT, 34-33

  6. Variability in the length of the sea ice season in the middle eocene arctic

    NARCIS (Netherlands)

    Stickley, C.E.; Koç, N.; Pearce, R.B.; Kemp, A.E.S.; Jordan, R.W.; Sangiorgi, F.; St. John, K.


    Finely laminated Middle Eocene sediments from the central Arctic contain high abundances of the delicate, sea ice–dwelling fossil diatoms Synedropsis spp. and sea ice–rafted debris (sea ice–IRD), establishing an offshore seasonal sea ice regime ca. 47 Ma. Synedropsis spp. co-occur with other

  7. Synchronous turnover of flora, fauna, and climate at the Eocene-Oligocene Boundary in Asia. (United States)

    Sun, Jimin; Ni, Xijun; Bi, Shundong; Wu, Wenyu; Ye, Jie; Meng, Jin; Windley, Brian F


    The Eocene-Oligocene Boundary (~34 million years ago) marks one of the largest extinctions of marine invertebrates in the world oceans and of mammalian fauna in Europe and Asia in the Cenozoic era. A shift to a cooler climate across this boundary has been suggested as the cause of this extinction in the marine environment, but there is no manifold evidence for a synchronous turnover of flora, fauna and climate at the Eocene-Oligocene Boundary in a single terrestrial site in Asia to support this hypothesis. Here we report new data of magnetostratigraphy, pollen and climatic proxies in the Asian interior across the Eocene-Oligocene Boundary; our results show that climate change forced a turnover of flora and fauna, suggesting there was a change from large-size perissodactyl-dominant fauna in forests under a warm-temperate climate to small rodent/lagomorph-dominant fauna in forest-steppe in a dry-temperate climate across the Eocene-Oligocene Boundary. These data provide a new terrestrial record for this significant Cenozoic environmental event.

  8. Changes in the hydrological cycle in tropical East Africa during the Paleocene-Eocene Thermal Maximum

    NARCIS (Netherlands)

    Handley, L.; O'Halloran, A.; Pearson, P.N.; Hawkins, E.; Nicholas, C.J.; Schouten, S.; McMillan, I.K.; Pancost, R.D.


    The Paleocene-Eocene Thermal Maximum (PETM), at ca. 55.8 Ma, is one of the most studied instances of past greenhouse gas-induced global warming. As such, it provides a rich opportunity to examine the impact of such global change on local climates. The effects of increased continental and sea surface

  9. Modelling the interactions between vegetation and climate from the Cretaceous to the Eocene (United States)

    Loptson, Claire; Lunt, Dan; Francis, Jane


    The climates during the Cretaceous (~144 to 66 Ma) and the early Eocene (~56 to 48 Ma) were much warmer than the present day. Atmospheric CO2 levels for these past climates have a large uncertainty associated with them, but were possibly as high as 2000 to 3000 ppm for the early Eocene (Beerling and Royer, 2011; Lowenstein and Demicco, 2006) and maximum values are thought to range from 800 to 1800 ppm during the Cretaceous (Royer et al., 2012). Current modelling efforts have had great difficulty in replicating the shallow latitudinal temperature gradient indicated by proxy data for these time periods (e.g. Heinemann et al., 2009; Winguth et al., 2010; Shellito et al., 2009). Mechanisms that can result in such a low temperature gradient have not been found (Winguth et al., 2010; Beerling et al., 2011; Sloan and Morrill, 1998), but a contributing factor could be that not all climate feedbacks are included in these models. Vegetation feedbacks have been shown to be especially important (e.g. Otto-Bliesner and Upchurch, 1997; Bonan, 2008) so by including a more accurate representation of vegetation in the climate model, the model-data discrepancies may be reduced. A fully coupled atmosphere-ocean GCM, HadCM3L, coupled to a dynamic global vegetation model (TRIFFID), was used to simulate the climate and the predicted vegetation distributions for and the early Eocene and 12 different time slices representing different ages throughout the Cretaceous at 4x pre-industrial CO2. The only difference in the way these simulations were set up are different boundary conditions that are specific to that time period, e.g. different solar constants and paleogeographies. This allows a direct comparison between the time slices. We present the changes in climate, and therefore vegetation, during the Cretaceous due to changes in these boundary conditions alone, with a focus on Antarctica. Additional Eocene simulations were also carried out with a) fixed globally-uniform vegetation and b

  10. Occurrence and distribution of bacterial tetraether lipids in the Eocene Canadian Arctic paleosols: paleoclimate implications (Invited) (United States)

    Mehay, S.; Jahren, A.; Schubert, B.; Eberle, J. J.; Summons, R. E.


    The Early to Middle Eocene (~56-45 Ma) was a “greenhouse” interval with average global temperatures warmer than any other time in the Cenozoic. This period was characterized by warm climates at high latitude leading to lush forests and the arrival of new mammal groups north of the Arctic Circle (>73°N). Glycerol dialkyl glycerol tetraethers (GDGTs) are membrane-spanning lipids characteristic of certain archaea and bacteria and it has been demonstrated that branched and cyclic GDGTs derived from soil bacteria vary in structure as a function of environmental factors. Proxies based on the relative abundances of methyl branched and cyclopentyl bacterial tetraethers are hypothesized to correlate with mean annual air temperature and soil pH. Here we present the occurrence and distribution of GDGTs in a range of paleosol and sediment samples from Axel Heiberg Island and Ellesmere Island, Nunavut (eastern Canadian Arctic) and Banks Island in the Northwest Territories (western Canadian Arctic). Preliminary results on 11 paleosol samples from the middle Eocene-aged Geodetic Hills Fossil Forest on Axel Heiberg Island indicate a mean annual air temperature of about 9°C. Earlier paleotemperature estimates for Axel Heiberg Island led to values ranging from 9°C to 15°C for the Middle Eocene. Recent temperature prediction for Ellesmere Island (Early Eocene) based upon oxygen isotope ratios of biogenic phosphate from mammal and fish fossils led to ~8°C. In contrast, GDGTs from a marine sedimentary sequence from Lomonosov Ridge in the central Arctic Ocean led to much higher Early Eocene temperature. Thus, the evaluation of the paleotemperature for the Early to Middle Eocene is still a subject of controversy. Ongoing GDGTs analysis of samples from Ellesmere and Banks Islands should give a more comprehensive paleoenvironmental description of the Eocene Arctic. Differences observed between the various paleotemperature estimates will also be discussed. GDGTs distributions are

  11. Identification of the Paleocene-Eocene boundary in coastal strata in the Otway Basin, Victoria, Australia (United States)

    Frieling, Joost; Huurdeman, Emiel P.; Rem, Charlotte C. M.; Donders, Timme H.; Pross, Jörg; Bohaty, Steven M.; Holdgate, Guy R.; Gallagher, Stephen J.; McGowran, Brian; Bijl, Peter K.


    Detailed, stratigraphically well-constrained environmental reconstructions are available for Paleocene and Eocene strata at a range of sites in the southwest Pacific Ocean (New Zealand and East Tasman Plateau; ETP) and Integrated Ocean Discovery Program (IODP) Site U1356 in the south of the Australo-Antarctic Gulf (AAG). These reconstructions have revealed a large discrepancy between temperature proxy data and climate models in this region, suggesting a crucial error in model, proxy data or both. To resolve the origin of this discrepancy, detailed reconstructions are needed from both sides of the Tasmanian Gateway. Paleocene-Eocene sedimentary archives from the west of the Tasmanian Gateway have unfortunately remained scarce (only IODP Site U1356), and no well-dated successions are available for the northern sector of the AAG. Here we present new stratigraphic data for upper Paleocene and lower Eocene strata from the Otway Basin, southeast Australia, on the (north)west side of the Tasmanian Gateway. We analyzed sediments recovered from exploration drilling (Latrobe-1 drill core) and outcrop sampling (Point Margaret) and performed high-resolution carbon isotope geochemistry of bulk organic matter and dinoflagellate cyst (dinocyst) and pollen biostratigraphy on sediments from the regional lithostratigraphic units, including the Pebble Point Formation, Pember Mudstone and Dilwyn Formation. Pollen and dinocyst assemblages are assigned to previously established Australian pollen and dinocyst zonations and tied to available zonations for the SW Pacific. Based on our dinocyst stratigraphy and previously published planktic foraminifer biostratigraphy, the Pebble Point Formation at Point Margaret is dated to the latest Paleocene. The globally synchronous negative carbon isotope excursion that marks the Paleocene-Eocene boundary is identified within the top part of the Pember Mudstone in the Latrobe-1 borehole and at Point Margaret. However, the high abundances of the

  12. Tectonic Reorganization and the Cause of Paleocene and Eocene pCO2 Anomalies (United States)

    Austermann, Jacqueline; Carter, Laura B.; Middleton, Jennifer; Stellmann, Jessica; Pyle, Lacey


    Oxygen isotope records reveal that deep-sea temperatures were relatively stable in the early and mid Paleocene before they rose by approx. 4°C to peak in the early Eocene. This Early Eocene Climate Optimum was followed by a 17 Myr cooling trend that led to the onset of Antarctic glaciation at the end of the Eocene. Several studies have examined the potential influence of perturbations to the sinks and sources of atmospheric carbon as mechanisms for the temperature drawdown over the Eocene. Examination of the changing magnitude of carbon sinks has focused on the importance of increased weathering associated with the uplift of the Tibetan plateau (Raymo and Ruddiman, 1992), the continental drift of basaltic provinces through the equatorial humid belt (Kent and Muttoni, 2013), or the emplacement of ophiolites during arc-continent collision in the face of a closing Tethys ocean (Jagoutz et al., 2016). With respect to carbon sources, the shutdown of Tethys subduction and related arc volcanism has been argued to significantly decrease carbon emissions and consequently global temperatures (Hoareau et al., 2015). In this study, we re-assess and quantify proposed atmospheric carbon sinks and sources to obtain an integrated picture of carbon flux changes over the Paleocene and Eocene and to estimate the relative importance of different mechanisms. To constrain carbon sources, we attempt to calculate the outgassing associated with large igneous provinces, mid-ocean ridges and volcanic arcs. We use plate reconstructions to track changes in length and divergence / convergence rates at plate boundaries as well as account for the onset and extinction of volcanic arcs. To constrain carbon sinks, we account for the sequestering of carbon due to silicate weathering and organic carbon burial. We again make use of plate reconstructions to trace highly weatherable arc systems and basaltic extrusions through the tropical humid belt and to assess the interplay between warmer Eocene

  13. Geochemistry and depositional environments of Paleocene-Eocene phosphorites: Metlaoui Group, Tunisia (United States)

    Garnit, Hechmi; Bouhlel, Salah; Jarvis, Ian


    The Late Paleocene-Early Eocene phosphorites of the Metlaoui Group in Tunisia are a world-class phosphate resource. We review the characteristics of phosphorites deposited in three areas: the Northern Basins; Eastern Basins; and Gafsa-Metlaoui Basin. Comprehensive new bulk rock elemental data are presented, together with complementary mineralogical and mineral chemical results. Carbonate fluorapatite (francolite) constitutes the dominant mineral phase in the deposits. Phosphorite samples are enriched in Cd, Sr, U, rare-earth elements and Y, together with environmentally diagnostic trace elements that provide detrital (Cr, Zr), productivity (Cu, Ni, Zn) and redox (Mo, V) proxies. Suboxic bottom-water conditions predominated, with suboxic to anoxic porewaters accompanying francolite precipitation. Phosphorite deposition occurred under increasingly arid climate conditions, accompanying global Paleocene-Eocene warming. The Northern Basins show the strongest Tethys Ocean influence, with surface seawater rare-earth element signatures consistently developed in the phosphorites. Bed-scale compositional variation indicates relatively unstable environmental conditions and episodes of sediment redeposition, with varying detrital supply and a relatively wet local climate. Glauconitic facies in the Northern Basins and the more isolated evaporite-associated phosphorites in the dryer Eastern Basins display the greatest diagenetic influences. The phosphorite - organic-rich marl - diatom-bearing porcelanite facies association in the Gafsa-Metlaoui Basin represents the classic coastal upwelling trinity. Modified Tethyan waters occurred within the Basin during phosphorite deposition, with decreasing marine productivity from NW to SE evidenced by systematically falling enrichment factors for Cu, Ni, Cd and Zn in the phosphorites. Productivity declined in concert with increasing basin isolation during the deposition of the commercial phosphorite beds in the latest Paleocene to earliest

  14. Analysis of Benthic Foraminiferal Size Change During the Eocene-Oligocene Transition (United States)

    Zachary, W.; Keating-Bitonti, C.


    The Eocene-Oligocene transition is a significant global cooling event with the first growth of continental ice on Antarctica. In the geologic record, the size of fossils can be used to indirectly observe how organisms respond to climate change. For example, organisms tend to be larger in cooler environments as a physiological response to temperature. This major global cooling event should influence organism physiology, resulting in significant size trends observed in the fossil record. Benthic foraminifera are protists and those that grow a carbonate shell are both well-preserved and abundant in marine sediments. Here, we used the foraminiferal fossil record to study the relationship between their size and global cooling. We hypothesize that cooler temperatures across the Eocene-Oligocene boundary promoted shell size increase. To test this hypothesis, we studied benthic foraminifera from 10 deep-sea cores drilled at Ocean Drilling Program Site 744, located in the southern Indian Ocean. We washed sediment samples over a 63-micron sieve and picked foraminifera from a 125-micron sieve. We studied the benthic foraminiferal genus Cibicidoides and its size change across this cooling event. Picked specimens were imaged and we measured the diameter of their shells using "imageJ". Overall, we find that Cibicidoides shows a general trend of increasing size during this transition. In particular, both the median and maximum sizes of Cibicidoides increase from the Eocene into the Oligocene. We also analyzed C. pachyderma and C. mundulus for size trends. Although both species increase in median size across the boundary, only C. pachyderma shows a consistent trend of increasing maximum, median, and minimum shell diameter. After the Eocene-Oligocene boundary, we observe that shell diameter decreases following peak cooling and that foraminiferal sizes remain stable into the early Oligocene. Therefore, the Eocene-Oligocene cooling event appears to have strong influence on shell size.

  15. Paleocene-Eocene magnetostratigraphy and climate-driven rock-magnetism from the Belluno Basin (Italy) (United States)

    Muttoni, G.; Dallanave, E.


    The magnetostratigraphy and rock-magnetism of the Paleocene-Eocene interval has been studied in the recent years in several Tethyan marine sections of the Belluno Basin of NE Italy (Possagno, Cicogna, South Ardo, Alano). The paleomagnetic results, integrated with calcareous nannofossil biostratigraphy, allowed the recovery of a virtually continuous ~27 Myr-long interval of time spanning from the K/Pg boundary (~65 Ma) at the South Ardo section up to the middle-late Eocene boundary (~38 Ma) at the Alano GSSP candidate, and bracketing some of the most extreme climate conditions of the Cenozoic such the Early Eocene climatic optimum (EECO) and the Paleocene-Eocene thermal maximum (PETM). The rock-magnetic data indicate that the magnetic mineralogy of the sediments generally consists of variable proportions of magnetite-maghemite-hematite, which are iron oxides characterized by different oxidation states and crystal structures. We reconstructed the rock-magnetic variability across the investigated interval, and placed it on a temporal reference frame using a CK95-based age-depth function for comparison with oxygen isotope data from the literature. The rock-magnetic data indicate that relatively warmer climate periods (i.e. the PETM and the early Eocene warming trend leading to EECO) are associated with high contents of detrital hematite relative to magnetite-maghemite, while relatively cooler climates (i.e. the Paleocene) are associated with a relative increase in magnetite-maghemite. We speculate that the increase of detrital hematite observed during warm periods is due to intensified chemical weathering rates of land silicates under warm and humid climates. We therefore show that rock-magnetic properties can be useful proxies to study the efficiency of the silicate weathering negative feedback mechanism to stabilize long-term Earth's surface temperatures.

  16. A Significant Warming Event in the Southern Ocean During the Late Middle Eocene (United States)

    Bohaty, S. M.; Zachos, J. C.


    The late middle-to-late Eocene (~45 to 34 Ma) is a critical period of Cenozoic climatic evolution, characterized by long-term cooling of deep waters and small-scale growth of ice sheets on Antarctica. This time interval, however, is poorly represented in deep-sea sediment archives, and high-resolution paleoceanographic records have not been developed for many of the sections that are available. Several Southern Ocean sites have adequate stratigraphic coverage through the middle-to-late Eocene and provide an opportunity to investigate regional paleoceanographic change through this time interval. In order to supplement the existing database, we have generated high-resolution stable isotope records from fine-fraction carbonates and foraminifera at Site 748, located on the southern Kerguelen Plateau. Integration of middle-to-late Eocene oxygen isotope records from Sites 748 and 738 (Kerguelen Plateau) and Site 689 (Maud Rise) reveals a prominent, short-term warming event at ~41.5 Ma, designated as the Middle Eocene Climatic Optimum (MECO). At Site 748, both surface-dwelling (Acarinina spp.) and benthic (Cibicidoides spp.) exhibit two δ 18O minima, indicating that this event is characterized by two brief intervals of peak warming in both surface and deep waters. Benthic foraminiferal δ 18O data further indicate that middle-bathyal waters warmed ~ 4°C on both the Kerguelen Plateau and Maud Rise during the MECO. Accordingly, this transient event (isotope excursion, as observed during the Paleocene-Eocene Thermal Maximum, suggests that this event was not triggered by methane dissociation. Instead, the MECO may possibly be linked to increased pCO2 associated with the Chron C20-19 plate reorganization. Possible sources of CO2 during this period of global tectonic change are metamorphic decarbonation in the Himalayan orogen and inter-plate volcanism.

  17. The Early Eocene equable climate problem: can perturbations of climate model parameters identify possible solutions? (United States)

    Sagoo, Navjit; Valdes, Paul; Flecker, Rachel; Gregoire, Lauren J


    Geological data for the Early Eocene (56-47.8 Ma) indicate extensive global warming, with very warm temperatures at both poles. However, despite numerous attempts to simulate this warmth, there are remarkable data-model differences in the prediction of these polar surface temperatures, resulting in the so-called 'equable climate problem'. In this paper, for the first time an ensemble with a perturbed climate-sensitive model parameters approach has been applied to modelling the Early Eocene climate. We performed more than 100 simulations with perturbed physics parameters, and identified two simulations that have an optimal fit with the proxy data. We have simulated the warmth of the Early Eocene at 560 ppmv CO2, which is a much lower CO2 level than many other models. We investigate the changes in atmospheric circulation, cloud properties and ocean circulation that are common to these simulations and how they differ from the remaining simulations in order to understand what mechanisms contribute to the polar warming. The parameter set from one of the optimal Early Eocene simulations also produces a favourable fit for the last glacial maximum boundary climate and outperforms the control parameter set for the present day. Although this does not 'prove' that this model is correct, it is very encouraging that there is a parameter set that creates a climate model able to simulate well very different palaeoclimates and the present-day climate. Interestingly, to achieve the great warmth of the Early Eocene this version of the model does not have a strong future climate change Charney climate sensitivity. It produces a Charney climate sensitivity of 2.7(°)C, whereas the mean value of the 18 models in the IPCC Fourth Assessment Report (AR4) is 3.26(°)C±0.69(°)C. Thus, this value is within the range and below the mean of the models included in the AR4.

  18. Atmospheric pCO2 reconstructed across five early Eocene global warming events (United States)

    Cui, Ying; Schubert, Brian A.


    Multiple short-lived global warming events, known as hyperthermals, occurred during the early Eocene (56-52 Ma). Five of these events - the Paleocene-Eocene Thermal Maximum (PETM or ETM1), H1 (or ETM2), H2, I1, and I2 - are marked by a carbon isotope excursion (CIE) within both marine and terrestrial sediments. The magnitude of CIE, which is a function of the amount and isotopic composition of carbon added to the ocean-atmosphere system, varies significantly between marine versus terrestrial substrates. Here we use the increase in carbon isotope fractionation by C3 land plants in response to increased pCO2 to reconcile this difference and reconstruct a range of background pCO2 and peak pCO2 for each CIE, provided two potential carbon sources: methane hydrate destabilization and permafrost-thawing/organic matter oxidation. Although the uncertainty on each pCO2 estimate using this approach is low (e.g., median uncertainty = + 23% / - 18%), this work highlights the potential for significant systematic bias in the pCO2 estimate resulting from sampling resolution, substrate type, diagenesis, and environmental change. Careful consideration of each of these factors is required especially when applying this approach to a single marine-terrestrial CIE pair. Given these limitations, we provide an upper estimate for background early Eocene pCO2 of 463 +248/-131 ppmv (methane hydrate scenario) to 806 +127/-104 ppmv (permafrost-thawing/organic matter oxidation scenario). These results, which represent the first pCO2 proxy estimates directly tied to the Eocene hyperthermals, demonstrate that early Eocene warmth was supported by background pCO2 less than ∼3.5× preindustrial levels and that pCO2 > 1000 ppmv may have occurred only briefly, during hyperthermal events.

  19. Characterization of circulating natural killer cells in neotropical primates.

    Directory of Open Access Journals (Sweden)

    Angela Carville

    Full Text Available Despite extensive use of nonhuman primates as models for infectious diseases and reproductive biology, imprecise phenotypic and functional definitions exist for natural killer (NK cells. This deficit is particularly significant in the burgeoning use of small, less expensive New World primate species. Using polychromatic flow cytometry, we identified peripheral blood NK cells as CD3-negative and expressing a cluster of cell surface molecules characteristic of NK cells (i.e., NKG2A, NKp46, NKp30 in three New World primate species - common marmosets, cotton-top tamarins, and squirrel monkeys. We then assessed subset distribution using the classical NK markers, CD56 and CD16. In all species, similar to Old World primates, only a minor subset of NK cells was CD56+, and the dominant subset was CD56-CD16+. Interestingly, CD56+ NK cells were primarily cytokine-secreting cells, whereas CD56-CD16+ NK cells expressed significantly greater levels of intracellular perforin, suggesting these cells might have greater potential for cytotoxicity. New World primate species, like Old World primates, also had a minor CD56-CD16- NK cell subset that has no obvious counterpart in humans. Herein we present phenotypic profiles of New World primate NK cell subpopulations that are generally analogous to those found in humans. This conservation among species should support the further use of these species for biomedical research.

  20. Comprehensive transcriptional map of primate brain development (United States)

    Bakken, Trygve E.; Miller, Jeremy A.; Ding, Song-Lin; Sunkin, Susan M.; Smith, Kimberly A.; Ng, Lydia; Szafer, Aaron; Dalley, Rachel A.; Royall, Joshua J.; Lemon, Tracy; Shapouri, Sheila; Aiona, Kaylynn; Arnold, James; Bennett, Jeffrey L.; Bertagnolli, Darren; Bickley, Kristopher; Boe, Andrew; Brouner, Krissy; Butler, Stephanie; Byrnes, Emi; Caldejon, Shiella; Carey, Anita; Cate, Shelby; Chapin, Mike; Chen, Jefferey; Dee, Nick; Desta, Tsega; Dolbeare, Tim A.; Dotson, Nadia; Ebbert, Amanda; Fulfs, Erich; Gee, Garrett; Gilbert, Terri L.; Goldy, Jeff; Gourley, Lindsey; Gregor, Ben; Gu, Guangyu; Hall, Jon; Haradon, Zeb; Haynor, David R.; Hejazinia, Nika; Hoerder-Suabedissen, Anna; Howard, Robert; Jochim, Jay; Kinnunen, Marty; Kriedberg, Ali; Kuan, Chihchau L.; Lau, Christopher; Lee, Chang-Kyu; Lee, Felix; Luong, Lon; Mastan, Naveed; May, Ryan; Melchor, Jose; Mosqueda, Nerick; Mott, Erika; Ngo, Kiet; Nyhus, Julie; Oldre, Aaron; Olson, Eric; Parente, Jody; Parker, Patrick D.; Parry, Sheana; Pendergraft, Julie; Potekhina, Lydia; Reding, Melissa; Riley, Zackery L.; Roberts, Tyson; Rogers, Brandon; Roll, Kate; Rosen, David; Sandman, David; Sarreal, Melaine; Shapovalova, Nadiya; Shi, Shu; Sjoquist, Nathan; Sodt, Andy J.; Townsend, Robbie; Velasquez, Lissette; Wagley, Udi; Wakeman, Wayne B.; White, Cassandra; Bennett, Crissa; Wu, Jennifer; Young, Rob; Youngstrom, Brian L.; Wohnoutka, Paul; Gibbs, Richard A.; Rogers, Jeffrey; Hohmann, John G.; Hawrylycz, Michael J.; Hevner, Robert F.; Molnár, Zoltán; Phillips, John W.; Dang, Chinh; Jones, Allan R.; Amaral, David G.; Bernard, Amy; Lein, Ed S.


    The transcriptional underpinnings of brain development remain poorly understood, particularly in humans and closely related non-human primates. We describe a high resolution transcriptional atlas of rhesus monkey brain development that combines dense temporal sampling of prenatal and postnatal periods with fine anatomical parcellation of cortical and subcortical regions associated with human neuropsychiatric disease. Gene expression changes more rapidly before birth, both in progenitor cells and maturing neurons, and cortical layers and areas acquire adult-like molecular profiles surprisingly late postnatally. Disparate cell populations exhibit distinct developmental timing but also unexpected synchrony of processes underlying neural circuit construction including cell projection and adhesion. Candidate risk genes for neurodevelopmental disorders including primary microcephaly, autism spectrum disorder, intellectual disability, and schizophrenia show disease-specific spatiotemporal enrichment within developing neocortex. Human developmental expression trajectories are more similar to monkey than rodent, and approximately 9% of genes show human-specific regulation with evidence for prolonged maturation or neoteny. PMID:27409810

  1. Neurogenetics of aggressive behavior: studies in primates. (United States)

    Barr, Christina S; Driscoll, Carlos


    Aggressive behavior can have adaptive value in certain environmental contexts, but when extreme or executed inappropriately, can also lead to maladaptive outcomes. Neurogenetic studies performed in nonhuman primates have shown that genetic variation that impacts reward sensitivity, impulsivity, and anxiety can contribute to individual differences in aggressive behavior. Genetic polymorphisms in the coding or promoter regions of the Mu-Opioid Receptor (OPRM1), Corticotropin Releasing Hormone (CRH), Monoamine Oxidase A (MAOA), Dopamine D4 Receptor (DRD4), and Serotonin Transporter (SLC6A4) genes have been shown to be functionally similar in humans and rhesus macaques and have been demonstrated to contribute to individual differences in aggression. This body of literature suggests mechanisms by which genetic variation that promotes aggressivity could simultaneously increase evolutionary success while making modern humans more vulnerable to psychopathology.

  2. IOP telemetry in the nonhuman primate. (United States)

    Downs, J Crawford


    This review is focused on continuous IOP monitoring using telemetry systems in the nonhuman primate (NHP), presented in the context that IOP fluctuations at various timescales may be involved in glaucoma pathogenesis and progression. We use glaucoma as the primary framework to discuss how the dynamic nature of IOP might change with age, racial heritage, and disease in the context of glaucoma susceptibility and progression. We focus on the limited work that has been published in IOP telemetry in NHPs, as well as the emerging data and approaches. We review the ongoing efforts to measure continuous IOP, and the strengths, weaknesses and general pitfalls of the various approaches. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Mediodorsal thalamus and cognition in nonhuman primates

    Directory of Open Access Journals (Sweden)

    Mark G Baxter


    Full Text Available Several recent studies in nonhuman primates have provided new insights into the role of the medial thalamus in different aspects of cognitive function. The mediodorsal nucleus of the thalamus (MD, by virtue of its connectivity with the frontal cortex, has been implicated in an array of cognitive functions. Rather than serving as an engine or relay for the prefrontal cortex, this area seems to be more specifically involved in regulating plasticity and flexibility of prefrontal-dependent cognitive functions. Focal damage to MD may also exacerbate the effects of damage to other subcortical relays. Thus a wide range of distributed circuits and cognitive functions may be disrupted from focal damage within the medial thalamus (for example as a consequence of stroke or brain injury. Conversely, this region may make an interesting target for neuromodulation of cognitive function via deep brain stimulation or related methods, in conditions associated with dysfunction of these neural circuits.

  4. The Evolution of Primate Communication and Metacommunication. (United States)

    Proust, Joëlle


    Against the prior view that primate communication is based only on signal decoding, comparative evidence suggests that primates are able, no less than humans, to intentionally perform or understand impulsive or habitual communicational actions with a structured evaluative nonconceptual content. These signals convey an affordance-sensing that immediately motivates conspecifics to act. Although humans have access to a strategic form of propositional communication adapted to teaching and persuasion, they share with nonhuman primates the capacity to communicate in impulsive or habitual ways. They are also similarly able to monitor fluency, informativeness and relevance of messages or signals through nonconceptual cues.

  5. Pathological rate matrices: from primates to pathogens

    Directory of Open Access Journals (Sweden)

    Knight Rob


    Full Text Available Abstract Background Continuous-time Markov models allow flexible, parametrically succinct descriptions of sequence divergence. Non-reversible forms of these models are more biologically realistic but are challenging to develop. The instantaneous rate matrices defined for these models are typically transformed into substitution probability matrices using a matrix exponentiation algorithm that employs eigendecomposition, but this algorithm has characteristic vulnerabilities that lead to significant errors when a rate matrix possesses certain 'pathological' properties. Here we tested whether pathological rate matrices exist in nature, and consider the suitability of different algorithms to their computation. Results We used concatenated protein coding gene alignments from microbial genomes, primate genomes and independent intron alignments from primate genomes. The Taylor series expansion and eigendecomposition matrix exponentiation algorithms were compared to the less widely employed, but more robust, Padé with scaling and squaring algorithm for nucleotide, dinucleotide, codon and trinucleotide rate matrices. Pathological dinucleotide and trinucleotide matrices were evident in the microbial data set, affecting the eigendecomposition and Taylor algorithms respectively. Even using a conservative estimate of matrix error (occurrence of an invalid probability, both Taylor and eigendecomposition algorithms exhibited substantial error rates: ~100% of all exonic trinucleotide matrices were pathological to the Taylor algorithm while ~10% of codon positions 1 and 2 dinucleotide matrices and intronic trinucleotide matrices, and ~30% of codon matrices were pathological to eigendecomposition. The majority of Taylor algorithm errors derived from occurrence of multiple unobserved states. A small number of negative probabilities were detected from the Pad�� algorithm on trinucleotide matrices that were attributable to machine precision. Although the Pad

  6. Early primate evolution in Afro-Arabia. (United States)

    Seiffert, Erik R


    The peculiar mammalian fauna that inhabited Afro-Arabia during the Paleogene first came to the attention of the scientific community in the early part of the twentieth century, when Andrews1 and Schlosser2 published their landmark descriptions of fossil mammals from the Fayum Depression in northern Egypt. Their studies revealed a highly endemic assemblage of land mammals that included the first known Paleogene records of hyraxes, proboscideans, and anthropoid primates, but which lacked ancestors of many iconic mammalian lineages that are found in Africa today, such as rhinos, zebras, bovids, giraffes, and cats. Over the course of the last century, the Afro-Arabian Paleogene has yielded fossil remains of several other endemic mammalian lineages,3 as well as a diversity of prosimian primates,4 but we are only just beginning to understand how the continent's faunal composition came to be, through ancient processes such as the movement of tectonic plates, changes in climate and sea level, and early phylogenetic splits among the major groups of placental mammals. These processes, in turn, made possible chance dispersal events that were critical in determining the competitive landscape--and, indeed, the survival--of our earliest anthropoid ancestors. Newly discovered fossils indicate that the persistence and later diversification of Anthropoidea was not an inevitable result of the clade's competitive isolation or adaptive superiority, as has often been assumed, but rather was as much due to the combined influences of serendipitous geographic conditions, global cooling, and competition with a group of distantly related extinct strepsirrhines with anthropoid-like adaptations known as adapiforms. Many of the important details of this story would not be known, and could never have been predicted, without the fossil evidence that has recently been unearthed by field paleontologists. Copyright © 2012 Wiley Periodicals, Inc.

  7. Social inequalities in health in nonhuman primates

    Directory of Open Access Journals (Sweden)

    Carol A. Shively


    Full Text Available Overall health has been linked to socioeconomic status, with the gap between social strata increasing each year. Studying the impact of social position on health and biological functioning in nonhuman primates has allowed researchers to model the human condition while avoiding ethical complexities or other difficulties characteristic of human studies. Using female cynomolgus macaques (Macaca fascicularis, our lab has examined the link between social status and stress for 30 years. Female nonhuman primates are especially sensitive to social stressors which can deleteriously affect reproductive health, leading to harmful consequences to their overall health. Subordinates have lower progesterone concentrations during the luteal phase of menstrual cycle, which is indicative of absence or impairment of ovulation. Subordinate animals receive more aggression, less affiliative attention, and are more likely to exhibit depressive behaviors. They also express higher stress-related biomarkers such as increased heart rates and lower mean cortisol. While no differences in body weight between dominant and subordinate animals are observed, subordinates have lower bone density and more visceral fat than their dominant counterparts. The latter increases risk for developing inflammatory diseases. Differences are also observed in neurological and autonomic function. A growing body of data suggests that diet composition may amplify or diminish physiological stress responses which have deleterious effects on health. More experimental investigation of the health effects of diet pattern is needed to further elucidate these differences in an ongoing search to find realistic and long-term solutions to the declining health of individuals living across the ever widening socioeconomic spectrum.

  8. Transgenic nonhuman primates for neurodegenerative diseases

    Directory of Open Access Journals (Sweden)

    Chan Anthony WS


    Full Text Available Abstract Animal models that represent human diseases constitute an important tool in understanding the pathogenesis of the diseases, and in developing effective therapies. Neurodegenerative diseases are complex disorders involving neuropathologic and psychiatric alterations. Although transgenic and knock-in mouse models of Alzheimer's disease, (AD, Parkinson's disease (PD and Huntington's disease (HD have been created, limited representation in clinical aspects has been recognized and the rodent models lack true neurodegeneration. Chemical induction of HD and PD in nonhuman primates (NHP has been reported, however, the role of intrinsic genetic factors in the development of the diseases is indeterminable. Nonhuman primates closely parallel humans with regard to genetic, neuroanatomic, and cognitive/behavioral characteristics. Accordingly, the development of NHP models for neurodegenerative diseases holds greater promise for success in the discovery of diagnoses, treatments, and cures than approaches using other animal species. Therefore, a transgenic NHP carrying a mutant gene similar to that of patients will help to clarify our understanding of disease onset and progression. Additionally, monitoring disease onset and development in the transgenic NHP by high resolution brain imaging technology such as MRI, and behavioral and cognitive testing can all be carried out simultaneously in the NHP but not in other animal models. Moreover, because of the similarity in motor repertoire between NHPs and humans, it will also be possible to compare the neurologic syndrome observed in the NHP model to that in patients. Understanding the correlation between genetic defects and physiologic changes (e.g. oxidative damage will lead to a better understanding of disease progression and the development of patient treatments, medications and preventive approaches for high risk individuals. The impact of the transgenic NHP model in understanding the role which

  9. Taste responsiveness to two steviol glycosides in three species of nonhuman primates


    Nicklasson, Sandra; Sjöström, Desirée; Amundin, Mats; Roth, Daniel; Hernandez Salazar, Laura Teresa; Laska, Matthias


    Primates have been found to differ widely in their taste perception and studies suggest that a co-evolution between plant species bearing a certain taste substance and primate species feeding on these plants may contribute to such between-species differences. Considering that only platyrrhine primates, but not catarrhine or prosimian primates, share an evolutionary history with the neotropical plant Stevia rebaudiana, we assessed whether members of these three primate taxa differ in their abi...

  10. Archiving and Databasing of Non-Human Primate Impact Data

    National Research Council Canada - National Science Library

    Dobie, Thomas


    The National Biodynamics Laboratory (NBDL) of the University of New Orleans has preserved recoverable indirect impact acceleration data from non-human primate subject tests performed by the former Naval Biodynamics Laboratory...

  11. Comparative Triceps Surae Morphology in Primates: A Review

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    Jandy B. Hanna


    Full Text Available Primate locomotor evolution, particularly the evolution of bipedalism, is often examined through morphological studies. Many of these studies have examined the uniqueness of the primate forelimb, and others have examined the primate hip and thigh. Few data exist, however, regarding the myology and function of the leg muscles, even though the ankle plantar flexors are highly important during human bipedalism. In this paper, we draw together data on the fiber type and muscle mass variation in the ankle plantar flexors of primates and make comparisons to other mammals. The data suggest that great apes, atelines, and lorisines exhibit similarity in the mass distribution of the triceps surae. We conclude that variation in triceps surae may be related to the shared locomotor mode exhibited by these groups and that triceps surae morphology, which approaches that of humans, may be related to frequent use of semiplantigrade locomotion and vertical climbing.

  12. A Model-Model and Data-Model Comparison for the Early Eocene Hydrological Cycle (United States)

    Carmichael, Matthew J.; Lunt, Daniel J.; Huber, Matthew; Heinemann, Malte; Kiehl, Jeffrey; LeGrande, Allegra; Loptson, Claire A.; Roberts, Chris D.; Sagoo, Navjit; Shields, Christine


    A range of proxy observations have recently provided constraints on how Earth's hydrological cycle responded to early Eocene climatic changes. However, comparisons of proxy data to general circulation model (GCM) simulated hydrology are limited and inter-model variability remains poorly characterised. In this work, we undertake an intercomparison of GCM-derived precipitation and P - E distributions within the extended EoMIP ensemble (Eocene Modelling Intercomparison Project; Lunt et al., 2012), which includes previously published early Eocene simulations performed using five GCMs differing in boundary conditions, model structure, and precipitation-relevant parameterisation schemes. We show that an intensified hydrological cycle, manifested in enhanced global precipitation and evaporation rates, is simulated for all Eocene simulations relative to the preindustrial conditions. This is primarily due to elevated atmospheric paleo-CO2, resulting in elevated temperatures, although the effects of differences in paleogeography and ice sheets are also important in some models. For a given CO2 level, globally averaged precipitation rates vary widely between models, largely arising from different simulated surface air temperatures. Models with a similar global sensitivity of precipitation rate to temperature (dP=dT ) display different regional precipitation responses for a given temperature change. Regions that are particularly sensitive to model choice include the South Pacific, tropical Africa, and the Peri-Tethys, which may represent targets for future proxy acquisition. A comparison of early and middle Eocene leaf-fossil-derived precipitation estimates with the GCM output illustrates that GCMs generally underestimate precipitation rates at high latitudes, although a possible seasonal bias of the proxies cannot be excluded. Models which warm these regions, either via elevated CO2 or by varying poorly constrained model parameter values, are most successful in simulating a

  13. A newly isolated Haloalkaliphilic bacterium from middle-late Eocene halite formed in salt lakes in China

    Czech Academy of Sciences Publication Activity Database

    Meng, F. W.; Wang, X.-Q.; Ni, P.; Kletetschka, Günther; Li, Y-P.; Yang, Ch.-H.


    Roč. 30, č. 3 (2015), s. 321-330 ISSN 0891-2556 Institutional support: RVO:67985831 Keywords : ancient microorganism * primary fluid inclusion * halite * Eocene Subject RIV: DB - Geology ; Mineralogy Impact factor: 0.440, year: 2015

  14. Molecular evolution of the primate antiviral restriction factor tetherin.

    Directory of Open Access Journals (Sweden)

    Jun Liu

    Full Text Available BACKGROUND: Tetherin is a recently identified antiviral restriction factor that restricts HIV-1 particle release in the absence of the HIV-1 viral protein U (Vpu. It is reminiscent of APOBEC3G and TRIM5a that also antagonize HIV. APOBEC3G and TRIM5a have been demonstrated to evolve under pervasive positive selection throughout primate evolution, supporting the red-queen hypothesis. Therefore, one naturally presumes that Tetherin also evolves under pervasive positive selection throughout primate evolution and supports the red-queen hypothesis. Here, we performed a detailed evolutionary analysis to address this presumption. METHODOLOGY/PRINCIPAL FINDINGS: Results of non-synonymous and synonymous substitution rates reveal that Tetherin as a whole experiences neutral evolution rather than pervasive positive selection throughout primate evolution, as well as in non-primate mammal evolution. Sliding-window analyses show that the regions of the primate Tetherin that interact with viral proteins are under positive selection or relaxed purifying selection. In particular, the sites identified under positive selection generally focus on these regions, indicating that the main selective pressure acting on the primate Tetherin comes from virus infection. The branch-site model detected positive selection acting on the ancestral branch of the New World Monkey lineage, suggesting an episodic adaptive evolution. The positive selection was also found in duplicated Tetherins in ruminants. Moreover, there is no bias in the alterations of amino acids in the evolution of the primate Tetherin, implying that the primate Tetherin may retain broad spectrum of antiviral activity by maintaining structure stability. CONCLUSIONS/SIGNIFICANCE: These results conclude that the molecular evolution of Tetherin may be attributed to the host-virus arms race, supporting the Red Queen hypothesis, and Tetherin may be in an intermediate stage in transition from neutral to pervasive

  15. Tolerance in Nonhuman Primates by Delayed Mixed Chimerism (United States)


    human primate model SA2: To investigate the effect of T memory cell inhibition and in-vivo T regulatory cell up regulation on the delayed induction of of the recipient to prevent rejection, remain significant areas in which improvement would enhance quality of life, improve the risk-benefit ratio...induction of mixed chimerism in a non- human primate (NHP) model. This approach, in contrast to protocols which have already reached clinical trials

  16. Male germline stem cells in non-human primates

    Directory of Open Access Journals (Sweden)

    S. Sharma


    Full Text Available Over the past few decades, several studies have attempted to decipher the biology of mammalian germline stem cells (GSCs. These studies provide evidence that regulatory mechanisms for germ cell specification and migration are evolutionarily conserved across species. The characteristics and functions of primate GSCs are highly distinct from rodent species; therefore the findings from rodent models cannot be extrapolated to primates. Due to limited availability of human embryonic and testicular samples for research purposes, two non-human primate models (marmoset and macaque monkeys are extensively employed to understand human germline development and differentiation. This review provides a broader introduction to the in vivo and in vitro germline stem cell terminology from primordial to differentiating germ cells. Primordial germ cells (PGCs are the most immature germ cells colonizing the gonad prior to sex differentiation into testes or ovaries. PGC specification and migratory patterns among different primate species are compared in the review. It also reports the distinctions and similarities in expression patterns of pluripotency markers (OCT4A, NANOG, SALL4 and LIN28 during embryonic developmental stages, among marmosets, macaques and humans. This review presents a comparative summary with immunohistochemical and molecular evidence of germ cell marker expression patterns during postnatal developmental stages, among humans and non-human primates. Furthermore, it reports findings from the recent literature investigating the plasticity behavior of germ cells and stem cells in other organs of humans and monkeys. The use of non-human primate models would enable bridging the knowledge gap in primate GSC research and understanding the mechanisms involved in germline development. Reported similarities in regulatory mechanisms and germ cell expression profile in primates demonstrate the preclinical significance of monkey models for development of

  17. The behavioral genetics of nonhuman primates: Status and prospects. (United States)

    Rogers, Jeffrey


    The complexity and diversity of primate behavior have long attracted the attention of ethologists, psychologists, behavioral ecologists, and neuroscientists. Recent studies have advanced our understanding of the nature of genetic influences on differences in behavior among individuals within species. A number of analyses have focused on the genetic analysis of behavioral reactions to specific experimental tests, providing estimates of the degree of genetic control over reactivity, and beginning to identify the genes involved. Substantial progress is also being made in identifying genetic factors that influence the structure and function of the primate brain. Most of the published studies on these topics have examined either cercopithecines or chimpanzees, though a few studies have addressed these questions in other primate species. One potentially important line of research is beginning to identify the epigenetic processes that influence primate behavior, thus revealing specific cellular and molecular mechanisms by which environmental experiences can influence gene expression or gene function relevant to behavior. This review summarizes many of these studies of non-human primate behavioral genetics. The primary focus is on analyses that address the nature of the genes and genetic processes that affect differences in behavior among individuals within non-human primate species. Analyses of between species differences and potential avenues for future research are also discussed. © 2018 American Association of Physical Anthropologists.

  18. The latest Paleocene to middle Eocene interval in the Bay of Biscay - preliminary results from calcareous nannofossils and planktic foraminifera (United States)

    Bornemann, A.


    Calcareous plankton (calcareous nannofossils, planktic foraminifera) is currently studied from DSDP Site 401 during the latest Paleocene to Middle Eocene greenhouse episode. This site is situated on the edge of a tilted fault block underlying the southern edge of the Meriadzek terrace on the North Biscay margin and comprises a 100-m-thick, nearly complete sedimentary record of Paleocene to middle Eocene sediments covering the Paleocene-Eocene Thermal Maximum as well as the Early Eocene Climatic Optimum. Detailed age control is achieved by calcareous nannofossil and planktic foraminiferal biostratigraphy suggesting that the study interval covers the NP9 to NP16 and P5 to E13 biozones, respectively, with a pronounced condensed interval across the Early to Middle Eocene boundary (NP13/NP14). Besides DSDP Site 550 this site represents one of the most northern locations which consists of Paleogene carbonates and will provide us a more complete picture by considering also long-term records from the northern hemisphere. Here we present first assemblage data from the two plankton groups which are accompanied by planktic and benthic foraminiferal oxygen and carbon isotope data in order to unravel the impact of the long-term climate change on the planktic ecosystem during the Eocene greenhouse.

  19. Functional Analysis of the Primate Shoulder. (United States)

    Preuschoft, Holger; Hohn, Bianca; Scherf, Heike; Schmidt, Manuela; Krause, Cornelia; Witzel, Ulrich


    Studies of the shoulder girdle are in most cases restricted to morphological comparisons and rarely aim at elucidating function in a strictly biomechanical sense. To fill this gap, we investigated the basic functional conditions that occur in the shoulder joint and shoulder girdle of primates by means of mechanics. Because most of nonhuman primate locomotion is essentially quadrupedal walking-although on very variable substrates-our analysis started with quadrupedal postures. We identified the mechanical situation at the beginning, middle, and end of the load-bearing stance phase by constructing force parallelograms in the shoulder joint and the scapulo-thoracal connection. The resulting postulates concerning muscle activities are in agreement with electromyographical data in the literature. We determined the magnitude and directions of the internal forces and explored mechanically optimal shapes of proximal humerus, scapula, and clavicula using the Finite Element Method. Next we considered mechanical functions other than quadrupedal walking, such as suspension and brachiation. Quadrupedal walking entails muscle activities and joint forces that require a long scapula, the cranial margin of which has about the same length as the axillary margin. Loading of the hand in positions above the head and suspensory behaviors lead to force flows along the axillary margin and so necessitate a scapula with an extended axillary and a shorter cranial margin. In all cases, the facies glenoidalis is nearly normal to the calculated joint forces. In anterior view, terrestrial monkeys chose a direction of the ground reaction force requiring (moderate) activity of the abductors of the shoulder joint, whereas more arboreal monkeys prefer postures that necessitate activity of the adductors of the forelimb even when walking along branches. The same adducting and retracting muscles are recruited in various forms of suspension. As a mechanical consequence, the scapula is in a more frontal

  20. Anthracobunids from the middle eocene of India and pakistan are stem perissodactyls. (United States)

    Cooper, Lisa Noelle; Seiffert, Erik R; Clementz, Mark; Madar, Sandra I; Bajpai, Sunil; Hussain, S Taseer; Thewissen, J G M


    Anthracobunidae is an Eocene family of large mammals from south Asia that is commonly considered to be part of the radiation that gave rise to elephants (proboscideans) and sea cows (sirenians). We describe a new collection of anthracobunid fossils from Middle Eocene rocks of Indo-Pakistan that more than doubles the number of known anthracobunid fossils and challenges their putative relationships, instead implying that they are stem perissodactyls. Cranial, dental, and postcranial elements allow a revision of species and the recognition of a new anthracobunid genus. Analyses of stable isotopes and long bone geometry together suggest that most anthracobunids fed on land, but spent a considerable amount of time near water. This new evidence expands our understanding of stem perissodactyl diversity and sheds new light on perissodactyl origins.

  1. Anthracobunids from the middle eocene of India and pakistan are stem perissodactyls.

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    Lisa Noelle Cooper

    Full Text Available Anthracobunidae is an Eocene family of large mammals from south Asia that is commonly considered to be part of the radiation that gave rise to elephants (proboscideans and sea cows (sirenians. We describe a new collection of anthracobunid fossils from Middle Eocene rocks of Indo-Pakistan that more than doubles the number of known anthracobunid fossils and challenges their putative relationships, instead implying that they are stem perissodactyls. Cranial, dental, and postcranial elements allow a revision of species and the recognition of a new anthracobunid genus. Analyses of stable isotopes and long bone geometry together suggest that most anthracobunids fed on land, but spent a considerable amount of time near water. This new evidence expands our understanding of stem perissodactyl diversity and sheds new light on perissodactyl origins.

  2. Strong Central Asian seasonality from Eocene oysters indicates early monsoons and aridification (United States)

    Bougeois, Laurie; de Rafélis, Marc; Tindall, Julia; Proust, Jean-Noël; Reichart, Gert-Jan; de Nooijer, Lennart; Guo, ZhaoJie; Ormukov, Cholponbek; Dupont-Nivet, Guillaume


    Climate models suggest that the onset of Asian monsoons and aridification have been governed by Tibetan plateau uplift, global climate changes and the retreat to the west of the vast epicontinental Proto-Paratethys sea during the warm Eocene greenhouse period (55-34 million years ago). However, the role of the Proto-Paratethys sea on climate remains to be quantified by accurate and precise reconstructions. By applying a novel intra-annual geochemical multi-proxy methodology on Eocene oyster shells of the Proto-Paratethys sea and comparing results to climate simulations and sedimentology analyses, we show that the Central Asian region was generally arid with a high seasonal contrast characterized by hot and arid summers and wetter winters. Hotter and more arid summers despite the presence of the Proto-Paratethys may be explained by warmer Eocene global conditions with a strong anticyclonic Hadley cell descending at Central Asian latitudes and a stronger Foehn effect from the emerging Tibetan Plateau to the south. This implies that the shallow sea did not have a strong dampening thermal effect on the monsoonal circulation in contrast to previous circulation models results but in agreement with recent evidence for Eocene summer monsoons. Enhanced winter precipitations, relative to modern, is linked to a westerly moisture source coming from the Proto-Paratethys sea at that time. Additional bulk sediment stable isotope data from marine limestones and pedogenic carbonates suggest a gradual decrease in this westerly moisture source, which is in line with the retreat of the Proto-Paratethys followed by the Oligo-Miocene orogeny of the Central Asian ranges (Tian Shan and Pamir) shielding the westerlies.

  3. Antarctic climate, Southern Ocean circulation patterns, and deep water formation during the Eocene (United States)

    Huck, Claire E.; van de Flierdt, Tina; Bohaty, Steven M.; Hammond, Samantha J.


    We assess early-to-middle Eocene seawater neodymium (Nd) isotope records from seven Southern Ocean deep-sea drill sites to evaluate the role of Southern Ocean circulation in long-term Cenozoic climate change. Our study sites are strategically located on either side of the Tasman Gateway and are positioned at a range of shallow (fish teeth at intermediate/deep Indian Ocean pelagic sites (Ocean Drilling Program (ODP) Sites 738 and 757 and Deep Sea Drilling Project (DSDP) Site 264), indicate a dominant Southern Ocean-sourced contribution to regional deep waters (ɛNd(t) = -9.3 ± 1.5). IODP Site U1356 off the coast of Adélie Land, a locus of modern-day Antarctic Bottom Water production, is identified as a site of persistent deep water formation from the early Eocene to the Oligocene. East of the Tasman Gateway an additional local source of intermediate/deep water formation is inferred at ODP Site 277 in the SW Pacific Ocean (ɛNd(t) = -8.7 ± 1.5). Antarctic-proximal shelf sites (ODP Site 1171 and Site U1356) reveal a pronounced erosional event between 49 and 48 Ma, manifested by 2 ɛNd unit negative excursions in seawater chemistry toward the composition of bulk sediments at these sites. This erosional event coincides with the termination of peak global warmth following the Early Eocene Climatic Optimum and is associated with documented cooling across the study region and increased export of Antarctic deep waters, highlighting the complexity and importance of Southern Ocean circulation in the greenhouse climate of the Eocene.

  4. Organic Geochemistry and Rock-Eval Pyrolysis of Eocene fine Sediments, East Ketungau Basin, West Kalimantan

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    M.H. Hermiyanto Zajuli


    Full Text Available DOI: 10.17014/ijog.v6i2.119Indonesia contains many Paleogene and Neogene basins which some of them have been proven to be a very prolific producer of oil and gas. A study on the result of Rock-Eval pyrolysis and biomarker undertaken on the Eocene Mandai Group was able to assess hydrocarbon potential of the Paleogene fine sediments in the frontier basin, especially West Kalimantan area. East Ketungau Basin is located in the western Kalimantan, bounded with Melawi Basin by the Semitau High in the south and West Ketungau Basin in the west. The Mandai Group was deposited in the East Ketungau Basin during Eocene, consisting of sandstone and mudstone facies. Mudstone facies comprises shale, claystone, and coal. Seven samples of Eocene fine sediments collected from East Ketungau Basin were analyzed by Rock-Eval pyrolisis and three samples for biomarker to evaluate their hydrocarbon potential. The Rock-Eval pyrolisis result of Mandai Group shows that TOC value of this facies ranges from 0.34 % to 5.16 %, Potential Yield (PY between 0.06 and 4.78 mg HC/g rock, and Hydrogen Index (HI from 12 to 89. Based on that result, the fine sediments of Mandai Group are included into a gas prone source rock potential with poor to fair categories. Moreover Tmax values vary from 426o C to 451o C. The Eocene fine sediments of Mandai Group fall under kerogen type III. Based on Tmax and biomarker analyses, the maturity of the sediments is situated within immature to mature level. The fine sediments of Mandai Group were deposited in a terrestrial to marine environment under anoxic to sub-oxic condition.

  5. Evidence for middle Eocene Arctic sea ice from diatoms and ice-rafted debris. (United States)

    Stickley, Catherine E; St John, Kristen; Koç, Nalân; Jordan, Richard W; Passchier, Sandra; Pearce, Richard B; Kearns, Lance E


    Oceanic sediments from long cores drilled on the Lomonosov ridge, in the central Arctic, contain ice-rafted debris (IRD) back to the middle Eocene epoch, prompting recent suggestions that ice appeared in the Arctic about 46 million years (Myr) ago. However, because IRD can be transported by icebergs (derived from land-based ice) and also by sea ice, IRD records are restricted to providing a history of general ice-rafting only. It is critical to differentiate sea ice from glacial (land-based) ice as climate feedback mechanisms vary and global impacts differ between these systems: sea ice directly affects ocean-atmosphere exchanges, whereas land-based ice affects sea level and consequently ocean acidity. An earlier report assumed that sea ice was prevalent in the middle Eocene Arctic on the basis of IRD, and although somewhat preliminary supportive evidence exists, these data are neither comprehensive nor quantified. Here we show the presence of middle Eocene Arctic sea ice from an extraordinary abundance of a group of sea-ice-dependent fossil diatoms (Synedropsis spp.). Analysis of quartz grain textural characteristics further supports sea ice as the dominant transporter of IRD at this time. Together with new information on cosmopolitan diatoms and existing IRD records, our data strongly suggest a two-phase establishment of sea ice: initial episodic formation in marginal shelf areas approximately 47.5 Myr ago, followed approximately 0.5 Myr later by the onset of seasonally paced sea-ice formation in offshore areas of the central Arctic. Our data establish a 2-Myr record of sea ice, documenting the transition from a warm, ice-free environment to one dominated by winter sea ice at the start of the middle Eocene climatic cooling phase.

  6. Palaeoceanographic and biotic response during early Eocene extreme global warming events. Geologica Ultraiectina (328)


    Stap, H.L.


    Studying past intervals of abrupt global warming and massive carbon release can improve our knowledge in ways relevant to understanding future climate change. Possible paleo-analogues for future climate change are the early Paleogene hyperthermal events, such as the Paleocene-Eocene Thermal Maximum (PETM; ~56 Ma), during which large amounts of carbon were released. More recently, another distinct period of global warming was discovered, similar in nature to the PETM, occurring approximately t...

  7. Goulds Belt, Interstellar Clouds, and the Eocene-Oligocene Helium-3 Spike (United States)

    Rubincam, David Parry


    Drag from hydrogen in the interstellar cloud which formed Gould's Belt may have sent small meteoroids with embedded helium to the Earth, perhaps explaining part or all of the (sup 3) He spike seen in the sedimentary record at the Eocene-Oligocene transition. Assuming the Solar System passed through part of the cloud, meteoroids in the asteroid belt up to centimeter size may have been dragged to the resonances, where their orbital eccentricities were pumped up into Earth-crossing orbits.

  8. Lower Paleogene Tectonostratigraphy of Balochistan: Evidence for Time-Transgressive Late Paleocene-Early Eocene Uplift

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    William C. Clyde


    Full Text Available Analysis of lithofacies, paleoflow directions, and sandstone petrography of upper Paleocene-lower Eocene paralic and continental sediments exposed along the transpressional suture zone of the western margin of the Indian plate indicate that the process of deformation and uplift of the carbonate shelf in this area had started by late Paleocene time. This tectonic uplift and deformation is documented by: (1 an overall shallowing upward synorogenic sequence of sediments, (2 proximal conglomerate facies (consisting of lower Paleocene and Mesozoic clasts dominating in the western part of the study area and distal facies of sandstone and shale dominating in the eastern part of the study area, (3 the existence of an unconformity of late Paleocene-early Eocene age in the Quetta and Kalat regions, (4 paleocurrent directions in deltaic and fluvial deposits indicating southeastward flowing sediment dispersal paths during late Paleocene-early Eocene time, which is opposite to that found in the late Cretaceous, suggesting a reversal in the depositional slope of the Cretaceous shelf, and (5 petrographic study of sandstones indicating a collision suture/fold thrust belt provenance. This episode of uplift and deformation could be the result of India-Arabian transpression with associated ophiolite obduction or, more likely, to represent the local response to initial India-Asia contact. The unroofing pattern and uplift geometry of the western Indian shelf suggests that this tectonism first started in the southern part of the study area (Kalat-Khuzdar area during the late Paleocene-early Eocene and proceeded northward in a time-transgressive fashion.

  9. Tarsal morphology of the pleuraspidotheriid mammal Hilalia from the middle Eocene of Turkey

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    Gregoire Metais


    Full Text Available Pleuraspidotheriids are a group of primitive ungulate mammals that, until recently, were thought to be restricted to the late Paleocene of Western Europe. It has been hypothesized that this family actually survived in Central Anatolia until at least the middle Eocene. However, these anachronistically young Anatolian “survivors”, including the genus Hilalia, were previously documented mainly by dental remains. Here, we describe the previously unknown astragalus of Hilalia saribeya, which confirms the pleuraspidotheriid affinities of the genus, and supports phylogenetic reconstructions that place Hilalia as the sister group of Pleuraspidotherium. The morphology of the astragalus suggests sub-cursorial plantigrade locomotion for H. saribeya, although its tarsal morphology remains generalized enough that scansorial capabilities cannot be ruled out. The evolution of Hilalia is addressed in the context of the apparent geographic isolation of Central Anatolia during the Eocene. The endemic character of the mammalian fauna of Central Anatolia during the middle Eocene emphasizes how the complex paleogeography of the northern margin of Neotethys impacted local biotas in a region situated at the crossroads of very distinctive biogeographic zones.

  10. Crown Group Lejeuneaceae and Pleurocarpous Mosses in Early Eocene (Ypresian Indian Amber.

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    Jochen Heinrichs

    Full Text Available Cambay amber originates from the warmest period of the Eocene, which is also well known for the appearance of early angiosperm-dominated megathermal forests. The humid climate of these forests may have triggered the evolution of epiphytic lineages of bryophytes; however, early Eocene fossils of bryophytes are rare. Here, we present evidence for lejeuneoid liverworts and pleurocarpous mosses in Cambay amber. The preserved morphology of the moss fossil is inconclusive for a detailed taxonomic treatment. The liverwort fossil is, however, distinctive; its zig-zagged stems, suberect complicate-bilobed leaves, large leaf lobules, and small, deeply bifid underleaves suggest a member of Lejeuneaceae subtribe Lejeuneinae (Harpalejeunea, Lejeunea, Microlejeunea. We tested alternative classification possibilities by conducting divergence time estimates based on DNA sequence variation of Lejeuneinae using the age of the fossil for corresponding age constraints. Consideration of the fossil as a stem group member of Microlejeunea or Lejeunea resulted in an Eocene to Late Cretaceous age of the Lejeuneinae crown group. This reconstruction is in good accordance with published divergence time estimates generated without the newly presented fossil evidence. Balancing available evidence, we describe the liverwort fossil as the extinct species Microlejeunea nyiahae, representing the oldest crown group fossil of Lejeuneaceae.

  11. Studies in neotropical paleobotany. XIV. A palynoflora from the middle Eocene Saramaguacan formation of Cuba (United States)

    Graham, A.; Cozadd, D.; Areces-Mallea, A.; Frederiksen, N.O.


    An assemblage of 46 fossil pollen and spore types is described from a core drilled through the middle Eocene Saramaguacan Formation, Camaguey Province, eastern Cuba. Many of the specimens represent unidentified or extinct taxa but several can be identified to family (Palmae, Bombacaceae, Gramineae, Moraceae, Myrtaceae) and some to genus (Pteris, Crudia, Lymingtonia?). The paleo-climate was warm-temperate to subtropical which is consistent with other floras in the region of comparable age and with the global paleotemperature curve. Older plate tectonic models show a variety of locations for proto-Cuba during Late Cretaceous and later times, including along the norther coast of South America. More recent models depict western and central Cuba as two separate parts until the Eocene, and eastern Cuba (joined to northern Hispaniola) docking to central Cuba also in the Eocene. All fragments are part of the North American Plate and none were directly connected with northern South America in late Mesozoic or Cenozoic time. The Saramaguacan flora supports this model because the assemblage is distinctly North American in affinities, with only one type (Retimonocolpites type 1) found elsewhere only in South America.

  12. Biogeographic and evolutionary implications of a diverse paleobiota in amber from the early Eocene of India (United States)

    Rust, Jes; Singh, Hukam; Rana, Rajendra S.; McCann, Tom; Singh, Lacham; Anderson, Ken; Sarkar, Nivedita; Nascimbene, Paul C.; Stebner, Frauke; Thomas, Jennifer C.; Solórzano Kraemer, Monica; Williams, Christopher J.; Engel, Michael S.; Sahni, Ashok; Grimaldi, David


    For nearly 100 million years, the India subcontinent drifted from Gondwana until its collision with Asia some 50 Ma, during which time the landmass presumably evolved a highly endemic biota. Recent excavations of rich outcrops of 50–52-million-year-old amber with diverse inclusions from the Cambay Shale of Gujarat, western India address this issue. Cambay amber occurs in lignitic and muddy sediments concentrated by near-shore chenier systems; its chemistry and the anatomy of associated fossil wood indicates a definitive source of Dipterocarpaceae. The amber is very partially polymerized and readily dissolves in organic solvents, thus allowing extraction of whole insects whose cuticle retains microscopic fidelity. Fourteen orders and more than 55 families and 100 species of arthropod inclusions have been discovered thus far, which have affinities to taxa from the Eocene of northern Europe, to the Recent of Australasia, and the Miocene to Recent of tropical America. Thus, India just prior to or immediately following contact shows little biological insularity. A significant diversity of eusocial insects are fossilized, including corbiculate bees, rhinotermitid termites, and modern subfamilies of ants (Formicidae), groups that apparently radiated during the contemporaneous Early Eocene Climatic Optimum or just prior to it during the Paleocene-Eocene Thermal Maximum. Cambay amber preserves a uniquely diverse and early biota of a modern-type of broad-leaf tropical forest, revealing 50 Ma of stasis and change in biological communities of the dipterocarp primary forests that dominate southeastern Asia today. PMID:20974929

  13. Sensitivity of the Palaeocene-Eocene Thermal Maximum climate to cloud properties. (United States)

    Kiehl, Jeffrey T; Shields, Christine A


    The Palaeocene-Eocene Thermal Maximum (PETM) was a significant global warming event in the Earth's history (approx. 55 Ma). The cause for this warming event has been linked to increases in greenhouse gases, specifically carbon dioxide and methane. This rapid warming took place in the presence of the existing Early Eocene warm climate. Given that projected business-as-usual levels of atmospheric carbon dioxide reach concentrations of 800-1100 ppmv by 2100, it is of interest to study past climates where atmospheric carbon dioxide was higher than present. This is especially the case given the difficulty of climate models in simulating past warm climates. This study explores the sensitivity of the simulated pre-PETM and PETM periods to change in cloud condensation nuclei (CCN) and microphysical properties of liquid water clouds. Assuming lower levels of CCN for both of these periods leads to significant warming, especially at high latitudes. The study indicates that past differences in cloud properties may be an important factor in accurately simulating past warm climates. Importantly, additional shortwave warming from such a mechanism would imply lower required atmospheric CO2 concentrations for simulated surface temperatures to be in reasonable agreement with proxy data for the Eocene.

  14. A Possible Late Paleocene-Early Eocene Ocean Acidification Event Recoded in the Adriatic Carbonate Platform (United States)

    Weiss, A.; Martindale, R. C.; Kosir, A.; Oefinger, J.


    The Paleocene-Eocene Thermal Maximum (PETM) event ( 56.3 Ma) was a period of massive carbon release into the Earth system, resulting in significant shifts in ocean chemistry. It has been proposed that ocean acidification - a decrease in the pH and carbonate saturation state of the water as a result of dissolved carbon dioxide in sea water - occurred in both the shallow and deep marine realms. Ocean acidification would have had a devastating impact on the benthic ecosystem, and has been proposed as the cause of decreased carbonate deposition in marine sections and coral reef collapse during the late Paleocene. To date, however, the only physical evidence of Paleocene-Eocene ocean acidification has been shown for offshore sites (i.e., a shallow carbonate compensation depth), but isotope analysis (i.e. B, I/Ca) suggests that acidification occurred in the shallow shelves as well. Several sites in the Kras region of Slovenia, has been found to contain apparent erosion surfaces coeval with the Paleocene-Eocene Boundary. We have investigated these potentially acidified horizons using petrography, stable carbon isotopes, cathodoluminescence, and elemental mapping. These datasets will inform whether the horizons formed by seafloor dissolution in an acidified ocean, or are due to subaerial exposure, or burial diagenesis (i.e. stylotization). Physical erosion and diagenesis can easily be ruled out based on field relationships and petrography, but the other potential causes must be analyzed more critically.

  15. Large temperature drop across the Eocene-Oligocene transition in central North America. (United States)

    Zanazzi, Alessandro; Kohn, Matthew J; MacFadden, Bruce J; Terry, Dennis O


    The Eocene-Oligocene transition towards a cool climate (approximately 33.5 million years ago) was one of the most pronounced climate events during the Cenozoic era. The marine record of this transition has been extensively studied. However, significantly less research has focused on continental climate change at the time, yielding partly inconsistent results on the magnitude and timing of the changes. Here we use a combination of in vivo stable isotope compositions of fossil tooth enamel with diagenetic stable isotope compositions of fossil bone to derive a high-resolution (about 40,000 years) continental temperature record for the Eocene-Oligocene transition. We find a large drop in mean annual temperature of 8.2 +/- 3.1 degrees C over about 400,000 years, the possibility of a small increase in temperature seasonality, and no resolvable change in aridity across the transition. The large change in mean annual temperature, exceeding changes in sea surface temperatures at comparable latitudes and possibly delayed in time with respect to marine changes by up to 400,000 years, explains the faunal turnover for gastropods, amphibians and reptiles, whereas most mammals in the region were unaffected. Our results are in agreement with modelling studies that attribute the climate cooling at the Eocene-Oligocene transition to a significant drop in atmospheric carbon dioxide concentrations.

  16. Eocene Loranthaceae pollen pushes back divergence ages for major splits in the family

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    Friðgeir Grímsson


    Full Text Available Background We revisit the palaeopalynological record of Loranthaceae, using pollen ornamentation to discriminate lineages and to test molecular dating estimates for the diversification of major lineages. Methods Fossil Loranthaceae pollen from the Eocene and Oligocene are analysed and documented using scanning-electron microscopy. These fossils were associated with molecular-defined clades and used as minimum age constraints for Bayesian node dating using different topological scenarios. Results The fossil Loranthaceae pollen document the presence of at least one extant root-parasitic lineage (Nuytsieae and two currently aerial parasitic lineages (Psittacanthinae and Loranthinae by the end of the Eocene in the Northern Hemisphere. Phases of increased lineage diversification (late Eocene, middle Miocene coincide with global warm phases. Discussion With the generation of molecular data becoming easier and less expensive every day, neontological research should re-focus on conserved morphologies that can be traced through the fossil record. The pollen, representing the male gametophytic generation of plants and often a taxonomic indicator, can be such a tracer. Analogously, palaeontological research should put more effort into diagnosing Cenozoic fossils with the aim of including them into modern systematic frameworks.

  17. Atmospheric CO2 variations on orbital time scale during the Paleocene and Eocene (United States)

    Zeebe, R. E.; Westerhold, T.; Littler, K.; Zachos, J. C.


    Multi-million-year proxy records (d13C, d18O, %CaCO3, Fe, etc.) show prominent variations on orbital time scale during the Paleocene and Eocene. The cycles have been identified at various sites across the globe and preferentially concentrate spectral power at eccentricity and precessional frequencies. It is almost certain that these cycles are an expression of changes in global climate and carbon cycling paced by orbital variations. However, little is currently known about (1) the driving mechanism linking orbital forcing to changes in climate and carbon cycling and (2) the amplitude of atmospheric CO2 variations associated with these cycles. We have used simple and complex carbon cycle models to explore the basic effect of different orbital forcing schemes and noise on the carbon cycle by forcing different carbon cycle parameters. For direct insolation forcing (opposed to eccentricity - tilt - precession), one major challenge is understanding how the system transfers spectral power from high to low frequencies. We will discuss feasible solutions to this problem, including insolation transformations analogous to electronic AC-DC conversion (DC'ing). Our results show that high-latitude mechanisms are unlikely drivers of orbitally paced changes in the Paleocene-Eocene Earth system. Based on a synthesis of modeling and proxy data analysis, we present the first estimates of orbital-scale variations in atmospheric CO2 during the Paleocene and Eocene.

  18. High resolution deep-sea stable isotopes: do Early Eocene hyperthermals share a common origin? (United States)

    Lauretano, Vittoria; Lourens, Lucas J.; Zachos, James C.; Sluijs, Appy


    During the Early Eocene, the Earth experienced a prolonged warming trend (55-50 Ma), punctuated by a series of short-lived global warming events known as "hyperthermals", of which the Paleocene-Eocene Thermal Maximum, (PETM) is the most extreme, followed by the ETM2 (Elmo) and the ETM3 ("X-event"). Along with these events, a number of less pronounced negative carbon isotope excursions, termed A to L by Cramer et al (2003), occurred throughout the Paleogene up to the Early Eocene Climatic Optimum (EECO). The drastic increase in temperature during the hyperthermals is associated with the release of large amounts of isotopically light carbon into the ocean-atmosphere system. Several hypotheses have been proposed to determine the sources and mechanisms of these carbon inputs, in particular the dissociation of marine gas hydrates. However, what still remains unclear is whether or not these events share a common source. To address this question we compare the quantitative relationship between high-resolution carbon and oxygen stable isotope records from benthic foraminiferal tests. A similar correspondence between changes in the carbon cycle and global temperature among the events, regardless of their magnitudes, would imply a similarity in their origins. Following Stap et al. 2010, we present the results of the comparison between our data and previously published data, using deep-sea material to extend the record to the I1-I2 events.

  19. Primate diversification inferred from phylogenies and fossils. (United States)

    Herrera, James P


    Biodiversity arises from the balance between speciation and extinction. Fossils record the origins and disappearance of organisms, and the branching patterns of molecular phylogenies allow estimation of speciation and extinction rates, but the patterns of diversification are frequently incongruent between these two data sources. I tested two hypotheses about the diversification of primates based on ∼600 fossil species and 90% complete phylogenies of living species: (1) diversification rates increased through time; (2) a significant extinction event occurred in the Oligocene. Consistent with the first hypothesis, analyses of phylogenies supported increasing speciation rates and negligible extinction rates. In contrast, fossils showed that while speciation rates increased, speciation and extinction rates tended to be nearly equal, resulting in zero net diversification. Partially supporting the second hypothesis, the fossil data recorded a clear pattern of diversity decline in the Oligocene, although diversification rates were near zero. The phylogeny supported increased extinction ∼34 Ma, but also elevated extinction ∼10 Ma, coinciding with diversity declines in some fossil clades. The results demonstrated that estimates of speciation and extinction ignoring fossils are insufficient to infer diversification and information on extinct lineages should be incorporated into phylogenetic analyses. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  20. Stereometrics In Primate Taxonomy And Phylogeny (United States)

    Creel, Norman


    Studies of the systematic relationships within the primate taxa Homo, Hylobatidae (lesser apes), Hominoidea (apes and man) and Colobinae (Asian and African leaf monkeys) are described. All are based in large part on multivariate statistical analyses of cranial morphology. Adequate quantification of the frequently complex and subtle differences in the morphology of the animals being compared, as well as the inclusion of statistically adequate samples of as many presumed species or other groups of interest as possible, are essential to the success of such analyses. Two methods of stereometric measurement have been developed to make this possible. In initial studies of the Hylobatidae and the Hominoidea, a simple mechanical device was designed which determines the tri-dimensional coordinates of an anatomical point by measuring an angle and two distances. An improved version was used in an investigation of Subsaharan human crania. In a taxonomic revision of the Colobinae now in progress, crania are photographed in several views with a pair of metric cameras; point coordinates are then measured in a modified stereoplotter and the views rotated mathematically into a single coordinate system. Although stereometrics is only one component in a complex system of analysis, it is an extremely important one. Taxonomic revisions of the described scope and depth could not be carried out with conventional methods of measurement without a much greater commitment of resources, if at all.

  1. No need to replace an "anomalous" primate (Primates) with an "anomalous" bear (Carnivora, Ursidae). (United States)

    Gutiérrez, Eliécer E; Pine, Ronald H


    By means of mitochondrial 12S rRNA sequencing of putative "yeti", "bigfoot", and other "anomalous primate" hair samples, a recent study concluded that two samples, presented as from the Himalayas, do not belong to an "anomalous primate", but to an unknown, anomalous type of ursid. That is, that they match 12S rRNA sequences of a fossil Polar Bear (Ursusmaritimus), but neither of modern Polar Bears, nor of Brown Bears (Ursusarctos), the closest relative of Polar Bears, and one that occurs today in the Himalayas. We have undertaken direct comparison of sequences; replication of the original comparative study; inference of phylogenetic relationships of the two samples with respect to those from all extant species of Ursidae (except for the Giant Panda, Ailuropodamelanoleuca) and two extinct Pleistocene species; and application of a non-tree-based population aggregation approach for species diagnosis and identification. Our results demonstrate that the very short fragment of the 12S rRNA gene sequenced by Sykes et al. is not sufficiently informative to support the hypotheses provided by these authors with respect to the taxonomic identity of the individuals from which these sequences were obtained. We have concluded that there is no reason to believe that the two samples came from anything other than Brown Bears. These analyses afforded an opportunity to test the monophyly of morphologically defined species and to comment on both their phylogenetic relationships and future efforts necessary to advance our understanding of ursid systematics.

  2. Integrated stratigraphy of a shallow marine Paleocene-Eocene boundary section, MCBR cores, Maryland (USA) (United States)

    Self-Trail, J. M.; Robinson, M. M.; Edwards, L. E.; Powars, D. S.; Wandless, G. A.; Willard, D. A.


    An exceptional Paleocene-Eocene boundary section occurs in a cluster of six short (Paleocene Aquia Formation and silty clay of the lower Eocene Marlboro Clay. Sediment samples were analyzed for carbon and oxygen isotopes, percent calcium carbonate, calcareous nannofossils, planktic and benthic foraminifera, dinoflagellates, pollen, and lithology. A well-defined carbon isotope excursion (CIE) documents a gradual negative shift in δ13C values that starts below the lithologic break between the Aquia Formation and the Marlboro Clay. A benthic foraminifer extinction event, reduction of calcareous nannofossil assemblages, and change in core color from gray to alternating gray and pink also occurs within the CIE transition. These alternating changes in color coincide with cyclic peaks in the carbon isotope and percent calcium carbonate curves, where gray color corresponds to a positive shift in carbon isotope values and to a corresponding increase in percent benthic and planktic foraminifera. The upper third of the Marlboro Clay is barren of all calcareous microfossil material, although the presence of foraminiferal molds and linings proves that deposition occurred in a marine environment. Co-occurrence of the dinoflagellates Apectodinium augustum and Phthanoperidinium crenulatum at the top of the Marlboro Clay suggests that the Marlboro Clay at Mattawoman Creek is truncated. This is corroborated by the absence in the Marlboro of specimens of the calcareous nannofossil Rhomboaster-Discoaster assemblage, which is restricted to early Eocene Zone NP9b. Based on planktic/benthic foraminifera ratios, deposition of sediments at Mattawoman Creek occurred predominantly in an inner neritic environment, at water depths between 25-50 m. Occasional deepening to approximately 75m (middle neritic environment) occurred in the early Eocene, as represented by the basal Marlboro Clay. The planktic/benthic ratio, however, could also be affected by surface productivity and/or river runoff

  3. Meaning, intention, and inference in primate vocal communication. (United States)

    Fischer, Julia; Price, Tabitha


    Two core questions in the study of speech evolution are whether nonhuman primate signals should be conceived as referential, and what the role of social cognition is in primate communication. Current evidence suggests that the structure of primate vocalizations is largely innate and related to the affective/motivational state of the caller, with a probabilistic and underdetermined relationship between specific events and calls. Moreover, nonhuman primates do not appear to express or comprehend communicative or informative intent, which is in line with a lack of mental state attribution to others. We argue that nonhuman primate vocalizations as well as gestures should be best conceived as goal-directed, where signallers are sensitive to the relation between their signalling and receivers' responses. Receivers in turn use signals to predict signaller behaviour. In combination with their ability to integrate information from multiple sources, this renders the system as a whole relatively powerful, despite the lack of higher-order intentionality on the side of sender or receiver. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  4. Functional comparison of innate immune signaling pathways in primates.

    Directory of Open Access Journals (Sweden)

    Luis B Barreiro


    Full Text Available Humans respond differently than other primates to a large number of infections. Differences in susceptibility to infectious agents between humans and other primates are probably due to inter-species differences in immune response to infection. Consistent with that notion, genes involved in immunity-related processes are strongly enriched among recent targets of positive selection in primates, suggesting that immune responses evolve rapidly, yet providing only indirect evidence for possible inter-species functional differences. To directly compare immune responses among primates, we stimulated primary monocytes from humans, chimpanzees, and rhesus macaques with lipopolysaccharide (LPS and studied the ensuing time-course regulatory responses. We find that, while the universal Toll-like receptor response is mostly conserved across primates, the regulatory response associated with viral infections is often lineage-specific, probably reflecting rapid host-virus mutual adaptation cycles. Additionally, human-specific immune responses are enriched for genes involved in apoptosis, as well as for genes associated with cancer and with susceptibility to infectious diseases or immune-related disorders. Finally, we find that chimpanzee-specific immune signaling pathways are enriched for HIV-interacting genes. Put together, our observations lend strong support to the notion that lineage-specific immune responses may help explain known inter-species differences in susceptibility to infectious diseases.

  5. Biology of primate relaxin: A paracrine signal in early pregnancy?

    Directory of Open Access Journals (Sweden)

    Hayes Eric S


    Full Text Available Abstract Relaxin is a peptide hormone that exerts numerous effects in a variety of tissues across a broad range of species. Although first identified more than 75 years ago interest in relaxin biology has waxed and waned over the years consistent with peaks and troughs of new experimental data on its wide-ranging biological effects and advances in relaxin enabling technologies. Recent insights into species-dependent differences in relaxin biology during pregnancy have once again stimulated a relative surge of interest in the study of relaxin's reproductive biology. Identification and pharmacological characterization of orphaned relaxin receptors and exploration of its paracrine effects on pregnancy using genomic and proteomic technologies have succeeded in fueling current interest in relaxin research. Primates and non-primate vertebrates exhibit very disparate profiles of relaxin genomics, proteomics and functional biology. Non-human primates appear to exhibit a very close similarity to humans with respect to relaxin reproductive biology but the similarities and subtle differences are only just beginning to be understood. We, and others, have shown that relaxin produces significant changes to the non-human primate endometrium during the peri-implantation period that are consistent with relaxin's long perceived role as a paracrine modulator of pregnancy. The purpose of this review is to summarize the reproductive biology of relaxin in non-human primates with a specific emphasis on the paracrine role of ovarian and endometrial relaxin during embryo implantation and early pregnancy.

  6. Primate Anatomy, Kinematics, and Principles for Humanoid Design (United States)

    Ambrose, Robert O.; Ambrose, Catherine G.


    The primate order of animals is investigated for clues in the design of Humanoid Robots. The pursuit is directed with a theory that kinematics, musculature, perception, and cognition can be optimized for specific tasks by varying the proportions of limbs, and in particular, the points of branching in kinematic trees such as the primate skeleton. Called the Bifurcated Chain Hypothesis, the theory is that the branching proportions found in humans may be superior to other animals and primates for the tasks of dexterous manipulation and other human specialties. The primate taxa are defined, contemporary primate evolution hypotheses are critiqued, and variations within the order are noted. The kinematic branching points of the torso, limbs and fingers are studied for differences in proportions across the order, and associated with family and genus capabilities and behaviors. The human configuration of a long waist, long neck, and short arms is graded using a kinematic workspace analysis and a set of design axioms for mobile manipulation robots. It scores well. The re emergence of the human waist, seen in early Prosimians and Monkeys for arboreal balance, but lost in the terrestrial Pongidae, is postulated as benefiting human dexterity. The human combination of an articulated waist and neck will be shown to enable the use of smaller arms, achieving greater regions of workspace dexterity than the larger limbs of Gorillas and other Hominoidea.

  7. PET imaging using parkinsonian primate model

    International Nuclear Information System (INIS)

    Nagai, Yuji


    Many animal models have been for studying neutrodegenerative diseases in humans. Among them, Parkinson's disease (PD) model in primates treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) is expected to be valid and useful in the field of regenerative medicine. MPTP-treated monkeys demonstrate parkinsonian syndrome, such as tremor, dyskinesia, rigidity, immobility, caused by the degeneration of dopamine neurons at the nigrostriatal pathway. In this model, investigation of cognitive impairment that is one of the important aspects of PD could be possible. We evaluated the degeneration process of nigrostriatal dopamine neurons with positron emission tomography (PET) using unanesthetized MPTP-treated two cynomolgus monkeys (Macaca fascicularis). The tracers used were [11C]PE2I, [11C]DOPA, [11C]raclopride for monitoring dopamine transporter (DAT) densities, dopamine (DA) turnover, dopamine D2-receptor (D2R) densities, respectively. The gross behavioral observation was also performed referring to the criteria of the PD symptoms. The motor dysfunction was not clearly observed up to the cumulative doses of 3 mg/kg MPTP. This period was called 'asymptomatic period'. As a result of PET scans in the asymptomatic period, DAT densities and DA turnover had already decreased greatly, but D2R densities had not changed clearly. These findings suggest that PET imaging can delineate the dopaminergic dysfunction in vivo even in the asymptomatic period. In human study of PD, it is reported that parkinsonism is shown after great loss of dopaminergic neutrons as well as pre-synaptic dysfunction. MPTP-treated monkeys demonstrate the parkinsonian syndrome with the similar mechanism as human PD. It can be expected that PET study with MPTP-monkeys would provide important clues relevant to the underlying cause of PD and be useful for preclinical study of regenerative medicine in this disease. (author)

  8. Convergence of complex cognitive abilities in cetaceans and primates. (United States)

    Marino, Lori


    What examples of convergence in higher-level complex cognitive characteristics exist in the animal kingdom? In this paper I will provide evidence that convergent intelligence has occurred in two distantly related mammalian taxa. One of these is the order Cetacea (dolphins, whales and porpoises) and the other is our own order Primates, and in particular the suborder anthropoid primates (monkeys, apes, and humans). Despite a deep evolutionary divergence, adaptation to physically dissimilar environments, and very different neuroanatomical organization, some primates and cetaceans show striking convergence in social behavior, artificial 'language' comprehension, and self-recognition ability. Taken together, these findings have important implications for understanding the generality and specificity of those processes that underlie cognition in different species and the nature of the evolution of intelligence. Copyright 2002 S. Karger AG, Basel

  9. Primate-specific evolution of an LDLR enhancer

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Qian-Fei; Prabhakar, Shyam; Wang, Qianben; Moses, Alan M.; Chanan, Sumita; Brown, Myles; Eisen, Michael B.; Cheng, Jan-Fang; Rubin,Edward M.; Boffelli, Dario


    Sequence changes in regulatory regions have often been invoked to explain phenotypic divergence among species, but molecular examples of this have been difficult to obtain. In this study we identified an anthropoid primate-specific sequence element that contributed to the regulatory evolution of the low-density lipoprotein receptor. Using a combination of close and distant species genomic sequence comparisons coupled with in vivo and in vitro studies, we found that a functional cholesterol-sensing sequence motif arose and was fixed within a pre-existing enhancer in the common ancestor of anthropoid primates. Our study demonstrates one molecular mechanism by which ancestral mammalian regulatory elements can evolve to perform new functions in the primate lineage leading to human.

  10. Primate brain size is predicted by diet but not sociality. (United States)

    DeCasien, Alex R; Williams, Scott A; Higham, James P


    The social brain hypothesis posits that social complexity is the primary driver of primate cognitive complexity, and that social pressures ultimately led to the evolution of the large human brain. Although this idea has been supported by studies indicating positive relationships between relative brain and/or neocortex size and group size, reported effects of different social and mating systems are highly conflicting. Here, we use a much larger sample of primates, more recent phylogenies, and updated statistical techniques, to show that brain size is predicted by diet, rather than multiple measures of sociality, after controlling for body size and phylogeny. Specifically, frugivores exhibit larger brains than folivores. Our results call into question the current emphasis on social rather than ecological explanations for the evolution of large brains in primates and evoke a range of ecological and developmental hypotheses centred on frugivory, including spatial information storage, extractive foraging and overcoming metabolic constraints.

  11. Primate vocalization, gesture, and the evolution of human language. (United States)

    Arbib, Michael A; Liebal, Katja; Pika, Simone


    The performance of language is multimodal, not confined to speech. Review of monkey and ape communication demonstrates greater flexibility in the use of hands and body than for vocalization. Nonetheless, the gestural repertoire of any group of nonhuman primates is small compared with the vocabulary of any human language and thus, presumably, of the transitional form called protolanguage. We argue that it was the coupling of gestural communication with enhanced capacities for imitation that made possible the emergence of protosign to provide essential scaffolding for protospeech in the evolution of protolanguage. Similarly, we argue against a direct evolutionary path from nonhuman primate vocalization to human speech. The analysis refines aspects of the mirror system hypothesis on the role of the primate brain's mirror system for manual action in evolution of the human language-ready brain.

  12. Analog VLSI-based modeling of the primate oculomotor system. (United States)

    Horiuchi, T K; Koch, C


    One way to understand a neurobiological system is by building a simulacrum that replicates its behavior in real time using similar constraints. Analog very large-scale integrated (VLSI) electronic circuit technology provides such an enabling technology. We here describe a neuromorphic system that is part of a long-term effort to understand the primate oculomotor system. It requires both fast sensory processing and fast motor control to interact with the world. A one-dimensional hardware model of the primate eye has been built that simulates the physical dynamics of the biological system. It is driven by two different analog VLSI chips, one mimicking cortical visual processing for target selection and tracking and another modeling brain stem circuits that drive the eye muscles. Our oculomotor plant demonstrates both smooth pursuit movements, driven by a retinal velocity error signal, and saccadic eye movements, controlled by retinal position error, and can reproduce several behavioral, stimulation, lesion, and adaptation experiments performed on primates.

  13. Importance of Achromatic Contrast in Short-Range Fruit Foraging of Primates


    Hiramatsu, Chihiro; Melin, Amanda D.; Aureli, Filippo; Schaffner, Colleen M.; Vorobyev, Misha; Matsumoto, Yoshifumi; Kawamura, Shoji


    Trichromatic primates have a 'red-green' chromatic channel in addition to luminance and 'blue-yellow' channels. It has been argued that the red-green channel evolved in primates as an adaptation for detecting reddish or yellowish objects, such as ripe fruits, against a background of foliage. However, foraging advantages to trichromatic primates remain unverified by behavioral observation of primates in their natural habitats. New World monkeys (platyrrhines) are an excellent model for this ev...

  14. Primate dental ecology: How teeth respond to the environment. (United States)

    Cuozzo, Frank P; Ungar, Peter S; Sauther, Michelle L


    Teeth are central for the study of ecology, as teeth are at the direct interface between an organism and its environment. Recent years have witnessed a rapid growth in the use of teeth to understand a broad range of topics in living and fossil primate biology. This in part reflects new techniques for assessing ways in which teeth respond to, and interact with, an organism's environment. Long-term studies of wild primate populations that integrate dental analyses have also provided a new context for understanding primate interactions with their environments. These new techniques and long-term field studies have allowed the development of a new perspective-dental ecology. We define dental ecology as the broad study of how teeth respond to, or interact with, the environment. This includes identifying patterns of dental pathology and tooth use-wear, as they reflect feeding ecology, behavior, and habitat variation, including areas impacted by anthropogenic disturbance, and how dental development can reflect environmental change and/or stress. The dental ecology approach, built on collaboration between dental experts and ecologists, holds the potential to provide an important theoretical and practical framework for inferring ecology and behavior of fossil forms, for assessing environmental change in living populations, and for understanding ways in which habitat impacts primate growth and development. This symposium issue brings together experts on dental morphology, growth and development, tooth wear and health, primate ecology, and paleontology, to explore the broad application of dental ecology to questions of how living and fossil primates interact with their environments. Copyright © 2012 Wiley Periodicals, Inc.

  15. Primate-Specific Evolution of an LDLR Enhancer

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Qian-fei; Prabhakar, Shyam; Wang, Qianben; Moses, Alan M.; Chanan, Sumita; Brown, Myles; Eisen, Michael B.; Cheng, Jan-Fang; Rubin,Edward M.; Boffelli, Dario


    Sequence changes in regulatory regions have often beeninvoked to explain phenotypic divergence among species, but molecularexamples of this have been difficult to obtain. In this study, weidentified an anthropoid primate specific sequence element thatcontributed to the regulatory evolution of the LDL receptor. Using acombination of close and distant species genomic sequence comparisonscoupled with in vivo and in vitro studies, we show that a functionalcholesterol-sensing sequence motif arose and was fixed within apre-existing enhancer in the common ancestor of anthropoid primates. Ourstudy demonstrates one molecular mechanism by which ancestral mammalianregulatory elements can evolve to perform new functions in the primatelineage leading to human.

  16. Middle Eocene Climatic Optimum linked to continental arc flare-up in Iran? (United States)

    van der Boon, A.; Kuiper, K.; van der Ploeg, R.; Cramwinckel, M.; Honarmand, M.; Sluijs, A.; Krijgsman, W.; Langereis, C. G.


    A 500 kyr episode of 3-5 °C gradual global climate warming, some 40 Myr ago, has been termed the Middle Eocene climatic optimum (MECO). It has been associated with a rise in atmospheric CO2 concentrations, but the source of this carbon remains enigmatic. We show, based on new Ar-Ar ages of volcanic rocks in Iran and Azerbaijan, that the time interval spanning the MECO was associated with a massive increase in continental arc volcanism. We also collected almost 300 Ar-Ar and U-Pb ages from literature. Typically, U-Pb ages from the Eocene are slightly younger, by 3 Myr, than Ar-Ar ages. We observed that U-Pb ages are obtained mostly from intrusive rocks and therefore must reflect an intrusive stage that post-dated extrusive volcanism. Combining all ages for extrusive rocks, we show that they cluster around 40.2 Ma, exactly within the time span of the MECO (40.5-40.0 Ma). We estimate volumes of volcanism based on a shapefile of outcrops and average thickness of the sequences. We calculate CO2 estimates using a relation volcanism-CO2 that was earlier used for the Deccan traps (Tobin et al., 2017). Our calculations indicate that the volume of the Iranian middle Eocene volcanic rocks (estimated at 37000 km3) is sufficient to explain the CO2 rise during the MECO. We conclude that continental arc flare-up in the Neotethys subduction zone is a plausible candidate for causing the MECO.

  17. Thermochronologic Evidence for Late Eocene Andean Mountain Building at 30°S (United States)

    Lossada, Ana C.; Giambiagi, Laura; Hoke, Gregory D.; Fitzgerald, Paul G.; Creixell, Christian; Murillo, Ismael; Mardonez, Diego; Velásquez, Ricardo; Suriano, Julieta


    The Andes between 28° and 30°S represent a transition between the Puna-Altiplano Plateau and the Frontal/Principal Cordillera fold-and-thrust belts to the south. While significant early Cenozoic deformation documented in the Andean Plateau, deciphering the early episodes of deformation during Andean mountain building in the transition area is largely unstudied. Apatite fission track (AFT) and (U-Th-Sm)/He (AHe) thermochronology from a vertical and a horizontal transect reveal the exhumation history of the High Andes at 30°S, an area at the heart of this major transition. Interpretation of the age-elevation profile, combined with inverse thermal modeling, indicates that the onset of rapid cooling was underway by 35 Ma, followed by a significant decrease in cooling rate at 30-25 Ma. AFT thermal models also reveal a second episode of rapid cooling in the early Miocene ( 18 Ma) related to rock exhumation to its present position. Low exhumation between the rapid cooling events allowed for the development of a partial annealing zone. We interpret the observed Eocene rapid exhumation as the product of a previously unrecognized compressive event in this part of the Andes that reflects a southern extension of Eocene orogenesis recognized in the Puna/Altiplano. Renewed early-Miocene exhumation indicates that the late Cenozoic compressional stresses responsible for the main phase of uplift of the South Central Andes also impacted the core of the range in this transitional sector. The major episode of Eocene exhumation suggests the creation of significant topographic relief in the High Andes earlier than previously thought.

  18. Frequency, magnitude and character of hyperthermal events at the onset of the Early Eocene Climatic Optimum (United States)

    Lauretano, V.; Littler, K.; Polling, M.; Zachos, J. C.; Lourens, L. J.


    Recent studies have shown that the Early Eocene Climatic Optimum (EECO) was preceded by a series of short-lived global warming events, known as hyperthermals. Here we present high-resolution benthic stable carbon and oxygen isotope records from ODP Sites 1262 and 1263 (Walvis Ridge, SE Atlantic) between ~ 54 and ~ 52 million years ago, tightly constraining the character, timing, and magnitude of six prominent hyperthermal events. These events, which include Eocene Thermal Maximum (ETM) 2 and 3, are studied in relation to orbital forcing and long-term trends. Our findings reveal an almost linear relationship between δ13C and δ18O for all these hyperthermals, indicating that the eccentricity-paced covariance between deep-sea temperature changes and extreme perturbations in the exogenic carbon pool persisted during these events towards the onset of the EECO, in accordance with previous observations for the Paleocene Eocene Thermal Maximum (PETM) and ETM2. The covariance of δ13C and δ18O during H2 and I2, which are the second pulses of the "paired" hyperthermal events ETM2-H2 and I1-I2, deviates with respect to the other events. We hypothesize that this could relate to a relatively higher contribution of an isotopically heavier source of carbon, such as peat or permafrost, and/or to climate feedbacks/local changes in circulation. Finally, the δ18O records of the two sites show a systematic offset with on average 0.2 ‰ heavier values for the shallower Site 1263, which we link to a slightly heavier isotopic composition of the intermediate water mass reaching the northeastern flank of the Walvis Ridge compared to that of the deeper northwestern water mass at Site 1262.

  19. Palaeocology of coal-bearing Eocene sediments in central Anatolia (Turkey) based on quantitative palynological data

    Energy Technology Data Exchange (ETDEWEB)

    Akkiraz, M.S.; Kayseri, M.S.; Akgun, F. [Dokuz Eylul University, Izmir (Turkey). Dept. of Geological Engineering


    In this study, the lignite-bearing Yoncali formation between Yozgat and Sorgun, in central Anatolia has been palynologically examined. Based on 37 outcrop samples, quantitative palynological studies recognized 64 genera and 136 palynoflora species in the palynological assemblage, which indicated a Middle-Late Eocene age. This paper also presents a quantitative palaeovegetation and palaeoclimate reconstruction for the Middle-Upper Eocene coal occurrences of Central Anatolia on the basis of palynomorph assemblages. The diversified floral and ecological characteristics of the pollen taxa indicates that the Middle-Upper Eocene formations in central Anatolia were characterized by the presence of a complex mangrove swamp with contributions by Nypa, Pelliciera, Avicennia, Diporites tszkaszentgydrgyi and dinoflagellate cysts which reflect warm climatic conditions. Lowland-riparian and montane elements are characterized by the dominance of Myricaceae, Symplocaceae, Icacinaceae, Quercus, Pinus and Castanea. Swamp-freshwater elements are represented by Sparganjaceae, Nymphaceae, Taxodjaceae, Cupressaceae and Nyssa as well as fern spores such as Osmundaceae and Gleicheniaceae. The calculations were performed with the help of the 'Coexistence Approach' method to climatically evaluate palynoflora from the Yozgat-Sorgun area. The obtained results have been compared to data derived from the application of the Coexistence Approach to other, already published Central Anatolian palynofloras of the same age. The results of the climatic inferences suggest that the palaeoclimatic conditions were in the megathermal zone, megatherm/mesotherm intermediate zone whereas mesothermic conditions prevailed in the montane region. Likewise, the results of mean annual range of temperatures indicate the influence of the Indian ocean, which enabled the development of the mangroves.

  20. Bichordites from the early Eocene of Cuba: significance in the evolutionary history of the spatangoids (United States)

    Villegas-Martín, Jorge; Netto, Renata Guimarães


    The trace fossil Bichordites monastiriensis is found in early Eocene turbiditic sandstones of the upper-slope deposits from the Capdevila Formation in Los Palacios Basin, Pinar del Río region, western Cuba. The potential tracemakers of B. monastiriensis include fossil spatangoids from the family Eupatagidae. The record of Bichordites in the deposits from Cuba allows to suppose that Eupatagidae echinoids were the oldest potential tracemakers of Bichordites isp. and reinforce the hypothesis that the ichnological record are relevant in envisaging the evolutionary history of the spatangoids.

  1. Coralgal facies of the Upper Eocene-Lower Oligocene limestones in Letca-Rastoci area

    Directory of Open Access Journals (Sweden)

    Ioana Prica


    Full Text Available In this paper are described the coralgal facies identified in the Upper Eocene-Lower Oligocene limestone succession (Cozla Formation outcropping in two quarries at Letca and Rastoci (Sălaj district, Romania. In the studied profiles the coral and algae limestones are interlayered with bioclastic limestones with foraminifera. On the top of relatively deep water deposits, coral and algae crusts and dendritic corals coated by algae were deposited. The environment registered a gradual deepening, the deposits being completely immersed, while bioclastic limestones with foraminifera were recurrently formed. This cycle is repeated, the whole succession being caracterized by several such “parasequences”.

  2. Mammal Dispersion linked to The Paleocene Eocene Thermal Maximum (PETM): New Insights from India. (United States)

    Khozyem, H.; Adatte, T.; Keller, G.; Spangenberg, J. E.; Bajpai, S.; Samant, B.; Mathur, S.


    The Paleocene Eocene Thermal Maximum (PETM, 55.5Ma) is globally related with the extinction of deep benthic foraminifera, the diversification of both plancktic foraminifera and mammals. In India, the tempo and timing of mammals dispersion, their association with the PETM or EECO (Early Eocene Climatic Optimum) and the India- Asia collision remain uncertain (Smith et al., 2006 Clementz, 2010). Three sections located in north and northwest India have been studied using sedimentology, micropaleontology, mineralogy (bulk and clay mineralogy) and geochemistry (stable isotopes, major and trace elements, organic matter). Both PETM and ETM2 (second Eocene Thermal Maximum, 53.7Ma), a short-lived warming episode that followed the PETM, are globally marked by a pronounced δ13Ccarb and org negative peak. Both isotopic excursions have been recognized in the Vastan and Tarkeswhar lignite mines (Cambay basin, Gujarat), above the main mammals bearing level. The lower shift is located above the first lignite seam (=lignite 2 of Sahni et al, 2004, 2009) and corresponds to the transition from continental to shallow marine conditions marked by benthic foraminifera and bivalves. The upper excursion appears to be linked to the ETM2 and corresponds to a second marine incursion containing bivalves, benthic (Nummulites burdigalensis) and planktic foraminifera located below the second lignite seam (lignite 1 of Sahni et al, 2004, 2009). A single but very pronounced δ13Corg peak has been detected in the Giral Lignite mine (Barmer, Rajhastan), around 6m above the vertebrates bearing level and may correspond to the PETM. This correlation is confirmed by palynological data (Tripathi et al., 2009, Sahni et al., 2004, 2009) and more particularly by an acme in the dinoflagellate Apectodinium that globally characterizes the PETM interval (Sluijs et al. 2007). Our micropaleontological data combined with stable carbone isotopes indicate the presence of both PETM and ETM2 events and constrain the

  3. New stalked and sessile cirripedes from the Eocene Mo Clay, northwest Jutland (Denmark)

    DEFF Research Database (Denmark)

    Carriol, René-Pierre; Bonde, Niels Christensøn; Jakobsen, Sten Lennart


    New taxa of thoracican cirripedes are recorded from the Eocene Mo Clay of northwest Jutland, Denmark, namely Stipilepas molerensis Carriol n. gen., n. sp., a scalpelliform gooseneck barnacle, and Plesiobrachylepas jutlandica Carriol n. gen., n. sp., a brachylepadomorph sessile form. This material...... is of importance in that the former not only represents the first extinct example of the tribe Ashinkailepadini, it also is the second fossil neolepadine, while the latter adds to the diversity of the family Brachylepadidae, which previously embraced only three genera. The geological context of these taxa...

  4. An exceptionally well-preserved Eocene dolichopodid fly eye: function and evolutionary significance (United States)

    Tanaka, Gengo; Parker, Andrew R.; Siveter, David J.; Maeda, Haruyoshi; Furutani, Masumi


    The exceptionally preserved eyes of an Eocene dolichopodid fly contained in Baltic amber show remarkable detail, including features at micrometre and submicrometre levels. Based on this material, we establish that it is likely that the neural superposition compound eye existed as far back as 45 Ma. The ommatidia have an open rhabdom with a trapezoidal arrangement of seven rhabdomeres. Such a structure is uniquely characteristic of the neural superposition compound eye of present-day flies. Optical analysis reveals that the fossil eyes had a sophisticated and efficient optical system. PMID:19129103

  5. Two new parrots (Psittaciformes) from the Lower Eocene Fur Formation of Denmark

    DEFF Research Database (Denmark)

    Waterhouse, David; Lindow, Bent Erik Kramer; Zelenkov, Nikita


    Two new fossil psittaciform birds from the Lower Eocene ‘Mo Clay' (Fur Formation) of Denmark (c. 54 Ma) are described. An unnamed specimen is assigned to the extinct avian family of stem-group parrots, Pseudasturidae (genus and species incertae sedis), while a second (Mopsitta tanta gen. et sp. nov.......) is the largest fossil parrot yet known. Both specimens are the first fossil records of these birds from Denmark. Although the phylogenetic position of Mopsitta is unclear (it is classified as family incertae sedis), this form is phylogenetically closer to Recent Psittacidae than to other known Palaeogene...

  6. Subfamily Limoniinae Speiser, 1909 (Diptera, Limoniidae) from Baltic amber (Eocene): the genus Helius Lepeletier & Serville, 1828. (United States)

    Kania, Iwona


    A revision of the genus Helius Lepeletier & Serville, 1828 (Diptera: Limoniidae) from Baltic amber (Eocene) is presented. Redescriptions of 5 species, Helius formosus Krzemiński, 1993, Helius linus Podenas, 2002, Helius minutus (Loew, 1850), Helius mutus Podenas, 2002, Helius pulcher (Loew, 1850) of this genus from Baltic amber are given and documented by photographs and drawings. Four new species of the genus Helius from Baltic amber are described: Helius gedanicus sp. nov., Helius hoffeinsorum sp. nov., Helius similis sp. nov., Helius fossilis sp. nov. A key to species of Helius from Baltic amber is provided. Patterns morphological evolution and the aspects evolutionary history of Helius are discussed.

  7. Tibetan garnet records early Eocene initiation of thickening in the Himalaya

    DEFF Research Database (Denmark)

    Smit, Matthijs Arjen; Hacker, Bradley; Lee, Jeffrey


    Tectonic reconstructions of the Himalayan orogeny depend on the age at which crustal thickening commenced. To investigate this age, we analyzed garnet from middle crustal rocks exposed in the north Himalayan Mabja and Kangmar gneiss domes of Tibet using Lu-Hf geochronology. Garnet yielded Lu-Hf a...... recrystallization during subsequent high-temperature ductile extension. The new Lu-Hf ages are the first to confirm that crustal thickening and contraction in the Tibetan Himalaya was broadly synchronous with the early Eocene collision between Greater India and the Eurasian plate...

  8. Climate, carbon cycling and marine ecology during the Paleocene-Eocene Thermal Maximum


    Frieling, J.


    The Paleocene and Eocene are characterized by strong greenhouse climates. Atmospheric CO2 concentrations and global temperatures were much higher than today. The period from 60 to 50 million years ago (Ma) is marked by a gradual warming trend of ~8 ºC in the deep ocean. The interval from 56 to 50 Ma is further characterized by several transient perturbations of the carbon cycle. Essentially, these perturbations, or “hyperthermal” events mark phases of rapid (103 – 104 years) warming, associat...

  9. Goulds Belt, Interstellar Clouds, and the Eocene Oligocene Helium-3 Enhancement (United States)

    Rubincam, David Parry


    Drag from hydrogen in the interstellar cloud which formed Gould's Belt may have sent interplanetary dust particle (IDPs) and small meteoroids with embedded helium to the Earth, perhaps explaining part the helium-3 flux increase seen in the sedimentary record near the Eocene-Oligocene transition. Assuming the Solar System passed through part of the cloud, IDPs in the inner Solar System may have been dragged to Earth, while dust and small meteoroids in the asteroid belt up to centimeter size may have been dragged to the resonances, where their orbital eccentricities were pumped up into Earth-crossing orbits; however, this hypotheses does not explain the Popigai and Chesapeake Bay impacts.

  10. Rectification of invalidly published new names for plants from the late Eocene of North Bohemia

    Directory of Open Access Journals (Sweden)

    Kvaček Zlatko


    Full Text Available Valid publication of new names of fossil plant taxa published since 1 January 1996 requires a diagnosis or description in English, besides other requirements included in the International Code of Nomenclature for algae, fungi, and plants (Melbourne Code adopted by the Eighteenth International Botanical Congress, Melbourne, Australia, July 2011 (McNeill et al. 2012. In order to validate names published from the late Eocene flora of the Staré Sedlo Formation, North Bohemia, diagnosed only in German (Knobloch et al. 1996, English translations are provided, including references to the type material and further relevant information.

  11. Fuenferrada 3, the first Eocene mammal locality in the depression of Montalbán (Teruel, Spain), with some remarks on the fauna of Olalla 4A

    NARCIS (Netherlands)

    Freudenthal, M.


    The rodent fauna of Fuenferrada contains two species of Theridomyidae and three species of Gliridae. It is compared with the Early Oligocene fauna of Olalla 4A, and with the Late Eocene fauna of Aguatón 2D. The absence of Cricetidae serves to determine its age as latest Eocene.

  12. Prolonged high relief in the northern Cordilleran orogenic front during middle and late Eocene extension based on stable isotope paleoaltimetry (United States)

    Fan, Majie; Constenius, Kurt N.; Dettman, David L.


    The paleoelevation and size of the North America Cordilleran orogen during the late Cretaceous-Paleogene contractional and subsequent extensional tectonics remain enigmatic. We present new estimates of paleorelief of the northern Cordilleran orogenic front during the middle and late Eocene using oxygen isotope compositions of unaltered molluscan fossils and paleosol carbonates in the Kishenehn basin. Bounded by several mountains ranges to the east, the Kishenehn basin was a half graben developed during middle Eocene to early Miocene collapse of the Cordilleran orogen. These mollusk taxa include three sympatric groups with affinities to wet tropical, semi-arid subtropical, and temperate environments. Our reconstructed surface water δ18O values vary between -19.8‰ and -6.3‰ (VSMOW) during the middle and late Eocene. The large differences in paleoenvironments and surface water δ18O values suggest that the catchment of the Kishenehn basin was at variable elevation. The estimated paleorelief between the basin and the surrounding mountains, based on both Rayleigh condensation model and predictions of Eocene precipitation isotope values using an isotope-enabled global climate model, is ∼4 km, and the basin floor was <1.5 km high. This high topography and high relief paleogeography suggest that the Cordilleran orogenic front reached an elevation of at least 4 km, and the crust thickness may have reached more than 55 km before Eocene gravitational collapse. We attribute the maintenance of high Eocene topography to the combination of an inherited thick crust, thermal uplift caused by mantle upwelling, and isostatic uplift caused by removing lower lithosphere or oceanic slab.

  13. Silicate weathering machine at work: Rock magnetic data from the late Paleocene-early Eocene Cicogna section, Italy (United States)

    Dallanave, Edoardo; Tauxe, Lisa; Muttoni, Giovanni; Rio, Domenico


    We describe a scenario of climate forcing on sedimentation recorded in the late Paleocene-early Eocene Cicogna marine section from the Belluno Basin (NE Italy). Previously published magneto-biostratigraphic data revealed that the ˜81 m Cicogna section extends from Chron C25r to Chron C23r spanning the NP7/NP8-NP12 nannofossil zones (˜52.2-56.6 Ma). Using previously published rock magnetic data, augmented by data from this study, we describe and thoroughly discuss a pronounced increase of hematite (relative to maghemite or magnetite) between ˜54.9 and 54.6 Ma immediately above the Paleocene-Eocene boundary, followed by a second, long-term increasing trend from ˜54 Ma up to ˜52.2 Ma in the early Eocene. This hematite is essentially of detrital origin, insofar as it is associated with a strong shallow bias of paleomagnetic inclinations, and is interpreted to have formed on land by the weathering of Fe-bearing silicates and other primary minerals. We speculate that the warm and humid climate typical of the Paleocene-Eocene thermal maximum (PETM, ˜54.9 Ma) as well as of the warming trend leading to the early Eocene climatic optimum (EECO; ˜52-50 Ma) enhanced continental weathering of silicate rocks with the consequent production, transport, and sedimentation of detrital hematite grains. This hypothesis is confirmed by a statistical correlation between the rock magnetic properties and global climate as revealed by a standard benthic oxygen isotope record from the literature. Our temporal coupling between oxidation state of sedimentary magnetic phases and global climate is therefore consistent with the existence in the Paleocene-Eocene of the silicate weathering negative feedback mechanism for the long-term stabilization of the Earth's surface temperature.

  14. Using non-human primates to benefit humans: research and organ transplantation. (United States)

    Shaw, David; Dondorp, Wybo; de Wert, Guido


    Emerging biotechnology may soon allow the creation of genetically human organs inside animals, with non-human primates (henceforth simply "primates") and pigs being the best candidate species. This prospect raises the question of whether creating organs in primates in order to then transplant them into humans would be more (or less) acceptable than using them for research. In this paper, we examine the validity of the purported moral distinction between primates and other animals, and analyze the ethical acceptability of using primates to create organs for human use.

  15. Modelling primate control of grasping for robotics applications

    CSIR Research Space (South Africa)

    Kleinhans, A


    Full Text Available -1 European Conference on Computer Vision (ECCV) Workshops, Zurich, Switzerland, 7 September 2014 Modelling primate control of grasping for robotics applications Ashley Kleinhans1, Serge Thill2, Benjamin Rosman1, Renaud Detry3 & Bryan Tripp4 1 CSIR...

  16. Locomotion and basicranial anatomy in primates and marsupials. (United States)

    Villamil, Catalina I


    There is ongoing debate in paleoanthropology about whether and how the anatomy of the cranium, and especially the cranial base, is evolving in response to locomotor and postural changes. However, the majority of studies focus on two-dimensional data, which fails to capture the complexity of cranial anatomy. This study tests whether three-dimensional cranial base anatomy is linked to locomotion or to other factors in primates (n = 473) and marsupials (n = 231). Results indicate that although there is a small effect of locomotion on cranial base anatomy in primates, this is not the case in marsupials. Instead, facial anatomy likely drives variation in cranial base anatomy in both primates and marsupials, with additional roles for body size and brain size. Although some changes to foramen magnum position and orientation are phylogenetically useful among the hominoids, they do not necessarily reflect locomotion or positional behavior. The interplay between locomotion, posture, and facial anatomy in primates requires further investigation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Serum Antibody Responses to Oral Microorganisms in Nonhuman Primates (United States)


    dentition. Nonhuman primates have a primary and permanent dentition which includes molars, premolars , canines and incisors. As has been described above, the...the last immunization. Silk sutures were ligated at the cementoenamel junction of all mandibular left second premolars and second molars to convert

  18. Molecular Evolution of the Glycosyltransferase 6 Gene Family in Primates

    Directory of Open Access Journals (Sweden)

    Eliane Evanovich


    Full Text Available Glycosyltransferase 6 gene family includes ABO, Ggta1, iGb3S, and GBGT1 genes and by three putative genes restricted to mammals, GT6m6, GTm6, and GT6m7, only the latter is found in primates. GT6 genes may encode functional and nonfunctional proteins. Ggta1 and GBGT1 genes, for instance, are pseudogenes in catarrhine primates, while iGb3S gene is only inactive in human, bonobo, and chimpanzee. Even inactivated, these genes tend to be conversed in primates. As some of the GT6 genes are related to the susceptibility or resistance to parasites, we investigated (i the selective pressure on the GT6 paralogs genes in primates; (ii the basis of the conservation of iGb3S in human, chimpanzee, and bonobo; and (iii the functional potential of the GBGT1 and GT6m7 in catarrhines. We observed that the purifying selection is prevalent and these genes have a low diversity, though ABO and Ggta1 genes have some sites under positive selection. GT6m7, a putative gene associated with aggressive periodontitis, may have regulatory function, but experimental studies are needed to assess its function. The evolutionary conservation of iGb3S in humans, chimpanzee, and bonobo seems to be the result of proximity to genes with important biological functions.

  19. As Threats of Violence Escalate, Primate Researchers Stand Firm. (United States)

    Schneider, Alison


    Scientists doing research on primates are increasingly being subjected to threats and acts of violence from animal rights groups. The intimidation has resulted in many laboratories taking extensive security measures. Some scientists claim, however, that there is no surrogate for animal research in understanding human diseases. There are fears that…

  20. Extensive diversity of intestinal trichomonads of non-human primates

    Czech Academy of Sciences Publication Activity Database

    Smejkalová, P.; Petrželková, Klára Judita; Pomajbíková, K.; Modrý, David; Čepička, I.


    Roč. 139, č. 1 (2012), s. 92-102 ISSN 0031-1820 R&D Projects: GA ČR GA206/09/0927 Institutional research plan: CEZ:AV0Z60930519; CEZ:AV0Z60220518 Keywords : trichomonads * Parabasalia * non-human primates * diversity * host specificity Subject RIV: EG - Zoology Impact factor: 2.355, year: 2012

  1. Distribution of the potto Perodictus potto (Primates: Lorisidae) in ...

    African Journals Online (AJOL)

    Journal of East African Natural History ... This paper (1) examines the Eastern Rift Valley as a major barrier to primate distribution in eastern Africa, (2) reviews the taxonomy of P. potto, (3) describes the distribution of the eastern potto P.p. ibeanus, (4) summarizes what is known about the body size, abundance, elevation ...

  2. Prosimian primates show ratio dependence in spontaneous quantity discriminations

    Directory of Open Access Journals (Sweden)

    Sarah Mychal Jones


    Full Text Available We directly tested the predictions of the approximate number system (ANS and the object file system in the spontaneous numerical judgments of prosimian primates. Prior work indicates that when human infants and a few species of nonhuman animals are given a single-trial choice between two sequentially baited buckets they choose the bucket with the greater amount of food but only when the quantities are small. This pattern of results has been interpreted as evidence that a limited capacity object-file system is used to track small numbers of objects and that the ANS is not invoked under these circumstances. Here we tested prosimian primates in food choice comparisons that were chosen to contrast predictions of the ANS and object-file systems. We found that prosimian primates consistently chose the larger of two sets when they differed by a 1:3 ratio regardless of whether both values were small (≤ 3, both values were large (> 3, or there was one small and one large value. Prosimians were not able to robustly discriminate quantities that differed by a 1:2 ratio for the same three conditions, nor did they show a preference for small quantities that differed by a 2:3 ratio. These results implicate the ANS in the spontaneous numerical discriminations of nonhuman primates.

  3. From Purgatorius ceratops to Homo sapiens - Primate Evolutionary ...

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 11; Issue 7. From Purgatorius ceratops to Homo sapiens - Primate Evolutionary History. Sindhu Radhakrishna. General Article Volume 11 Issue 7 July 2006 pp 51-60. Fulltext. Click here to view fulltext PDF. Permanent link:

  4. Human quadrupeds, primate quadrupedalism, and Uner Tan Syndrome.

    Directory of Open Access Journals (Sweden)

    Liza J Shapiro

    Full Text Available Since 2005, an extensive literature documents individuals from several families afflicted with "Uner Tan Syndrome (UTS," a condition that in its most extreme form is characterized by cerebellar hypoplasia, loss of balance and coordination, impaired cognitive abilities, and habitual quadrupedal gait on hands and feet. Some researchers have interpreted habitual use of quadrupedalism by these individuals from an evolutionary perspective, suggesting that it represents an atavistic expression of our quadrupedal primate ancestry or "devolution." In support of this idea, individuals with "UTS" are said to use diagonal sequence quadrupedalism, a type of quadrupedal gait that distinguishes primates from most other mammals. Although the use of primate-like quadrupedal gait in humans would not be sufficient to support the conclusion of evolutionary "reversal," no quantitative gait analyses were presented to support this claim. Using standard gait analysis of 518 quadrupedal strides from video sequences of individuals with "UTS", we found that these humans almost exclusively used lateral sequence-not diagonal sequence-quadrupedal gaits. The quadrupedal gait of these individuals has therefore been erroneously described as primate-like, further weakening the "devolution" hypothesis. In fact, the quadrupedalism exhibited by individuals with UTS resembles that of healthy adult humans asked to walk quadrupedally in an experimental setting. We conclude that quadrupedalism in healthy adults or those with a physical disability can be explained using biomechanical principles rather than evolutionary assumptions.

  5. A review of lateralization of spatial functioning in nonhuman primates

    NARCIS (Netherlands)

    Oleksiak, Anna; Postma, Albert; van der Ham, Ineke J. M.; Klink, P. Christiaan; van Wezel, Richard J. A.


    The majority of research on functional cerebral lateralization in primates revolves around vocal abilities, addressing the evolutionary origin of the human language faculty and its predominance in the left hemisphere of the brain. Right hemisphere specialization in spatial cognition is commonly

  6. A review of lateralization of spatial functioning in nonhuman primates

    NARCIS (Netherlands)

    Oleksiak, Anna; Postma, Albert; van der Ham, Ineke J.M.; Klink, P. Christiaan; van Wezel, Richard Jack Anton

    The majority of research on functional cerebral lateralization in primates revolves around vocal abilities, addressing the evolutionary origin of the human language faculty and its predominance in the left hemisphere of the brain. Right hemisphere specialization in spatial cognition is commonly

  7. The gateway to the brain: dissecting the primate eye. (United States)

    Burke, Mark; Zangenehpour, Shahin; Bouskila, Joseph; Boire, Denis; Ptito, Maurice


    The visual system in humans is considered the gateway to the world and plays a principal role in the plethora of sensory, perceptual and cognitive processes. It is therefore not surprising that quality of vision is tied to quality of life . Despite widespread clinical and basic research surrounding the causes of visual disorders, many forms of visual impairments, such as retinitis pigmentosa and macular degeneration, lack effective treatments. Non-human primates have the closest general features of eye development to that of humans. Not only do they have a similar vascular anatomy, but amongst other mammals, primates have the unique characteristic of having a region in the temporal retina specialized for high visual acuity, the fovea(1). Here we describe a general technique for dissecting the primate retina to provide tissue for retinal histology, immunohistochemistry, laser capture microdissection, as well as light and electron microscopy. With the extended use of the non-human primate as a translational model, our hope is that improved understanding of the retina will provide insights into effective approaches towards attenuating or reversing the negative impact of visual disorders on the quality of life of affected individuals.

  8. Adaptive evolution of facial colour patterns in Neotropical primates. (United States)

    Santana, Sharlene E; Lynch Alfaro, Jessica; Alfaro, Michael E


    The rich diversity of primate faces has interested naturalists for over a century. Researchers have long proposed that social behaviours have shaped the evolution of primate facial diversity. However, the primate face constitutes a unique structure where the diverse and potentially competing functions of communication, ecology and physiology intersect, and the major determinants of facial diversity remain poorly understood. Here, we provide the first evidence for an adaptive role of facial colour patterns and pigmentation within Neotropical primates. Consistent with the hypothesis that facial patterns function in communication and species recognition, we find that species living in smaller groups and in sympatry with a higher number of congener species have evolved more complex patterns of facial colour. The evolution of facial pigmentation and hair length is linked to ecological factors, and ecogeographical rules related to UV radiation and thermoregulation are met by some facial regions. Our results demonstrate the interaction of behavioural and ecological factors in shaping one of the most outstanding facial diversities of any mammalian lineage.

  9. Nonhuman Primate IFITM Proteins Are Potent Inhibitors of HIV and SIV.

    Directory of Open Access Journals (Sweden)

    Jordan Wilkins

    Full Text Available Interferon-induced transmembrane (IFITM proteins are potent antiviral factors shown to restrict the infection of many enveloped viruses, including HIV. Here we report cloning and characterization of a panel of nonhuman primate IFITMs. We show that, similar to human IFITM, nonhuman primate IFITM proteins inhibit HIV and other primate lentiviruses. While some nonhuman primate IFITM proteins are more potent than human counterparts to inhibit HIV-1, they are generally not effective against HIV-2 similar to that of human IFITMs. Notably, depending on SIV strains and also IFITM species tested, nonhuman primate IFITM proteins exhibit distinct activities against SIVs; no correlation was found to support the notion that IFITM proteins are most active in non-natural primate hosts. Consistent with our recent findings for human IFITMs, nonhuman primate IFITM proteins interact with HIV-1 Env and strongly act in viral producer cells to impair viral infectivity and block cell-to-cell transmission. Accordingly, knockdown of primate IFITM3 increases HIV-1 replication in nohuman primate cells. Interestingly, analysis of DNA sequences of human and nonhuman primate IFITMs suggest that IFITM proteins have been undergoing purifying selection, rather than positive selection typical for cellular restriction factors. Overall, our study reveals some new and unexpected features of IFITMs in restricting primate lentiviruses, which enhances our understanding of virus-host interaction and AIDS pathogenesis.

  10. Nonhuman Primate IFITM Proteins Are Potent Inhibitors of HIV and SIV. (United States)

    Wilkins, Jordan; Zheng, Yi-Min; Yu, Jingyou; Liang, Chen; Liu, Shan-Lu


    Interferon-induced transmembrane (IFITM) proteins are potent antiviral factors shown to restrict the infection of many enveloped viruses, including HIV. Here we report cloning and characterization of a panel of nonhuman primate IFITMs. We show that, similar to human IFITM, nonhuman primate IFITM proteins inhibit HIV and other primate lentiviruses. While some nonhuman primate IFITM proteins are more potent than human counterparts to inhibit HIV-1, they are generally not effective against HIV-2 similar to that of human IFITMs. Notably, depending on SIV strains and also IFITM species tested, nonhuman primate IFITM proteins exhibit distinct activities against SIVs; no correlation was found to support the notion that IFITM proteins are most active in non-natural primate hosts. Consistent with our recent findings for human IFITMs, nonhuman primate IFITM proteins interact with HIV-1 Env and strongly act in viral producer cells to impair viral infectivity and block cell-to-cell transmission. Accordingly, knockdown of primate IFITM3 increases HIV-1 replication in nohuman primate cells. Interestingly, analysis of DNA sequences of human and nonhuman primate IFITMs suggest that IFITM proteins have been undergoing purifying selection, rather than positive selection typical for cellular restriction factors. Overall, our study reveals some new and unexpected features of IFITMs in restricting primate lentiviruses, which enhances our understanding of virus-host interaction and AIDS pathogenesis.

  11. Quality management for the international transportation of non-human primates

    Directory of Open Access Journals (Sweden)

    David B. Elmore


    Full Text Available Safe and humane transportation of live animals requires dedicated, informed personnel who carefully plan and attend to the details of appropriate animal care and handling throughout the shipping process. Specifically, although transportation of non-human primates shares goals common to all live animal transport, it also poses unique challenges stemming from the nature of these animals. Some of these unique challenges of transporting non-human primates, include the impact of public perception of non-human primates as cargo, maintaining biosecurity of non-human primate cargo, safety of both the non-human primate and public contacts, meeting the vital husbandry needs of varying species of non-human primates and compliance with numerous regulatory agencies, which may have overlapping responsibilities. This discussion will focus on these important considerations, as they relate to the legal international transportation of non-human primates for scientific use.

  12. Reproductive/developmental toxicity and immunotoxicity assessment in the nonhuman primate model

    International Nuclear Information System (INIS)

    Buse, Eberhard; Habermann, Gunnar; Osterburg, Ingrid; Korte, Rainhart; Weinbauer, Gerhard F.


    Nonhuman primates are being used increasingly as a non-rodent animal model during preclinical toxicology and safety assessment on the basis of proven similarity and comparability between nonhuman primates and humans. The validity of the nonhuman primate models applies to many aspects of toxicological testing and holds particularly true for the evaluation of reproductive toxicology and developmental toxicology. More recently, the advent of humanized antibodies and vaccines imposed further demand on nonhuman primate models since many immunotherapeutics do not interact with rodent receptors but frequently only cross-react with primate tissue. In this paper we discuss the suitability of primate models for reproductive, developmental and immunotoxicology testing, and present our initial data on the development of lymphatic organs and immune system in a nonhuman primate model

  13. Anti-tetherin activities in Vpu-expressing primate lentiviruses

    Directory of Open Access Journals (Sweden)

    Haworth Kevin G


    Full Text Available Abstract Background The anti-viral activity of the cellular restriction factor, BST-2/tetherin, was first observed as an ability to block the release of Vpu-minus HIV-1 from the surface of infected cells. However, tetherin restriction is also counteracted by primate lentiviruses that do not express a Vpu protein, where anti-tetherin functions are provided by either the Env protein (HIV-2, SIVtan or the Nef protein (SIVsm/mac and SIVagm. Within the primate lentiviruses, Vpu is also present in the genomes of SIVcpz and certain SIVsyk viruses. We asked whether, in these viruses, anti-tetherin activity was always a property of Vpu, or if it had selectively evolved in HIV-1 to perform this function. Results We found that despite the close relatedness of HIV-1 and SIVcpz, the chimpanzee viruses use Nef instead of Vpu to counteract tetherin. Furthermore, SIVcpz Nef proteins had activity against chimpanzee but not human tetherin. This specificity mapped to a short sequence that is present in the cytoplasmic tail of primate but not human tetherins, and this also accounts for the specificity of SIVsm/mac Nef for primate but not human tetherins. In contrast, Vpu proteins from four diverse members of the SIVsyk lineage all displayed an anti-tetherin activity that was active against macaque tetherin. Interestingly, Vpu from a SIVgsn isolate was also found to have activity against human tetherin. Conclusions Primate lentiviruses show a high degree of flexibility in their use of anti-tetherin factors, indicating a strong selective pressure to counteract tetherin restriction. The identification of an activity against human tetherin in SIVgsn Vpu suggests that the presence of Vpu in the ancestral SIVmus/mon/gsn virus believed to have contributed the 3' half of the HIV-1 genome may have played a role in the evolution of viruses that could counteract human tetherin and infect humans.

  14. Evolutionary molecular cytogenetics of catarrhine primates: past, present and future. (United States)

    Stanyon, R; Rocchi, M; Bigoni, F; Archidiacono, N


    The catarrhine primates were the first group of species studied with comparative molecular cytogenetics. Many of the fundamental techniques and principles of analysis were initially applied to comparisons in these primates, including interspecific chromosome painting, reciprocal chromosome painting and the extensive use of cloned DNA probes for evolutionary analysis. The definition and importance of chromosome syntenies and associations for a correct cladistics analysis of phylogenomic relationships were first applied to catarrhines. These early chromosome painting studies vividly illustrated a striking conservation of the genome between humans and macaques. Contemporarily, it also revealed profound differences between humans and gibbons, a group of species more closely related to humans, making it clear that chromosome evolution did not follow a molecular clock. Chromosome painting has now been applied to more that 60 primate species and the translocation history has been mapped onto the major taxonomic divisions in the tree of primate evolution. In situ hybridization of cloned DNA probes, primarily BAC-FISH, also made it possible to more precisely map breakpoints with spanning and flanking BACs. These studies established marker order and disclosed intrachromosomal rearrangements. When applied comparatively to a range of primate species, they led to the discovery of evolutionary new centromeres as an important new category of chromosome evolution. BAC-FISH studies are intimately connected to genome sequencing, and probes can usually be assigned to a precise location in the genome assembly. This connection ties molecular cytogenetics securely to genome sequencing, assuring that molecular cytogenetics will continue to have a productive future in the multidisciplinary science of phylogenomics. Copyright © 2012 S. Karger AG, Basel.

  15. Longitudinal characterization of Escherichia coli in healthy captive nonhuman primates

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    Jonathan B Clayton


    Full Text Available The gastrointestinal (GI tracts of nonhuman primates are well known to harbor Escherichia coli, a known commensal of humans and animals. While E. coli is a normal inhabitant of the mammalian gut, it also exists in a number of pathogenic forms or pathotypes, including those with predisposition for the GI tract, as well the urogenital tract. Diarrhea in captive nonhuman primates (NHPs has long been a problem in both zoo settings and research colonies, including the Como Zoo. It is an animal welfare concern, as well as a public health concern. E. coli has not been extensively studied in correlation with diarrhea in captive primates; therefore, a study was performed during the summer of 2009 in collaboration with a zoo in Saint Paul, MN, which was experiencing an increased incidence and severity of diarrhea among their NHP collection. Fresh fecal samples were collected weekly from each member of the primate collection, between June and August of 2009, and E. coli were isolated. A total of 33 individuals were included in the study, representing eight species. E. coli isolates were examined for their genetic relatedness, phylogenetic relationships, plasmid replicon types, virulence gene profiles, and antimicrobial susceptibility profiles. A number of isolates were identified containing virulence genes commonly found in several different E. coli pathotypes, and there was evidence of clonal transmission of isolates between animals and over time. Overall, the manifestation of chronic diarrhea in the Como Zoo primate collection is a complex problem whose solution will require regular screening for microbial agents and consideration of environmental causes. This study provides some insight towards the sharing of enteric bacteria between such animals.

  16. Sequential palynostratigraphy of the Queen City and Weches formations (Middle Eocene Claiborne Group), southeast central Texas

    Energy Technology Data Exchange (ETDEWEB)

    Elsik, W.C. (MycoStrat Connection, Houston, TX (United States))


    Palynomorph sequences of several orders of magnitude were found in the Queen City and Weches formations respectively at Six Mile and Burleson bluffs on the Brazos River, Milam and Burleson counties, Texas. The long term development of the subtropical to tropical Claibornian palynoflora included Engelhardtia spp., Friedrichipollis claibornensis, Nudopollis terminalis, Pollenites laesius and Symplocoipollenites spp. Shorter term fluctuations in sea level were reflected by common herbaceous pollen in the Queen City, and common mangrove pollen in the Weches. Paleoenvironments were marginally to fully marine; dinocysts occurred throughout. The Wetzeliella group of dinocysts were present only in the Queen City at Six Mile Bluff. Late Paleocene to Early Eocene pollen, and Early Middle Eocene pollen with last effective occurrences near the Queen City and Weches boundary included Aesculiidites circumstriatus, Annona foveoreticulata and a new species of Platycarya. Five short term warmer-cooler couplet events were represented by successive abundance peaks of Juglandaceae followed by Ulmus; Alnus supports the three upper Ulmus peaks. One deep water event was recorded by an abundance of fresh water Pediastrum at the Queen City and Weches boundary. That boundary event was bracketed by two of the Alnus and Ulmus peaks.

  17. Characterization of petroleum reservoirs in the Eocene Green River Formation, Central Uinta Basin, Utah (United States)

    Morgan, C.D.; Bereskin, S.R.


    The oil-productive Eocene Green River Formation in the central Uinta Basin of northeastern Utah is divided into five distinct intervals. In stratigraphically ascending order these are: 1) Uteland Butte, 2) Castle Peak, 3) Travis, 4) Monument Butte, and 5) Beluga. The reservoir in the Uteland Butte interval is mainly lacustrine limestone with rare bar sandstone beds, whereas the reservoirs in the other four intervals are mainly channel and lacustrine sandstone beds. The changing depositional environments of Paleocene-Eocene Lake Uinta controlled the characteristics of each interval and the reservoir rock contained within. The Uteland Butte consists of carbonate and rare, thin, shallow-lacustrine sandstone bars deposited during the initial rise of the lake. The Castle Peak interval was deposited during a time of numerous and rapid lake-level fluctuations, which developed a simple drainage pattern across the exposed shallow and gentle shelf with each fall and rise cycle. The Travis interval records a time of active tectonism that created a steeper slope and a pronounced shelf break where thick cut-and-fill valleys developed during lake-level falls and rises. The Monument Butte interval represents a return to a gentle, shallow shelf where channel deposits are stacked in a lowstand delta plain and amalgamated into the most extensive reservoir in the central Uinta Basin. The Beluga interval represents a time of major lake expansion with fewer, less pronounced lake-level falls, resulting in isolated single-storied channel and shallow-bar sandstone deposits.

  18. Micro-halocline enabled nutrient recycling may explain extreme Azolla event in the Eocene Arctic Ocean. (United States)

    van Kempen, Monique M L; Smolders, Alfons J P; Lamers, Leon P M; Roelofs, Jan G M


    In order to understand the physicochemical mechanisms that could explain the massive growth of Azolla arctica in the Eocene Arctic Ocean, we carried out a laboratory experiment in which we studied the interacting effects of rain and wind on the development of salinity stratification, both in the presence and in the absence of a dense Azolla cover. Additionally, we carried out a mesocosm experiment to get a better understanding of the nutrient cycling within and beneath a dense Azolla cover in both freshwater and brackish water environments. Here we show that Azolla is able to create a windproof, small-scale salinity gradient in brackish waters, which allows for efficient recycling of nutrients. We suggest that this mechanism ensures the maintenance of a large standing biomass in which additional input of nutrients ultimately result in a further expansion of an Azolla cover. As such, it may not only explain the extent of the Azolla event during the Eocene, but also the absence of intact vegetative Azolla remains and the relatively low burial efficiency of organic carbon during this interval.

  19. Micro-halocline enabled nutrient recycling may explain extreme Azolla event in the Eocene Arctic Ocean.

    Directory of Open Access Journals (Sweden)

    Monique M L van Kempen

    Full Text Available In order to understand the physicochemical mechanisms that could explain the massive growth of Azolla arctica in the Eocene Arctic Ocean, we carried out a laboratory experiment in which we studied the interacting effects of rain and wind on the development of salinity stratification, both in the presence and in the absence of a dense Azolla cover. Additionally, we carried out a mesocosm experiment to get a better understanding of the nutrient cycling within and beneath a dense Azolla cover in both freshwater and brackish water environments. Here we show that Azolla is able to create a windproof, small-scale salinity gradient in brackish waters, which allows for efficient recycling of nutrients. We suggest that this mechanism ensures the maintenance of a large standing biomass in which additional input of nutrients ultimately result in a further expansion of an Azolla cover. As such, it may not only explain the extent of the Azolla event during the Eocene, but also the absence of intact vegetative Azolla remains and the relatively low burial efficiency of organic carbon during this interval.

  20. Antarctic glaciation caused ocean circulation changes at the Eocene-Oligocene transition. (United States)

    Goldner, A; Herold, N; Huber, M


    Two main hypotheses compete to explain global cooling and the abrupt growth of the Antarctic ice sheet across the Eocene-Oligocene transition about 34 million years ago: thermal isolation of Antarctica due to southern ocean gateway opening, and declining atmospheric CO2 (refs 5, 6). Increases in ocean thermal stratification and circulation in proxies across the Eocene-Oligocene transition have been interpreted as a unique signature of gateway opening, but at present both mechanisms remain possible. Here, using a coupled ocean-atmosphere model, we show that the rise of Antarctic glaciation, rather than altered palaeogeography, is best able to explain the observed oceanographic changes. We find that growth of the Antarctic ice sheet caused enhanced northward transport of Antarctic intermediate water and invigorated the formation of Antarctic bottom water, fundamentally reorganizing ocean circulation. Conversely, gateway openings had much less impact on ocean thermal stratification and circulation. Our results support available evidence that CO2 drawdown--not gateway opening--caused Antarctic ice sheet growth, and further show that these feedbacks in turn altered ocean circulation. The precise timing and rate of glaciation, and thus its impacts on ocean circulation, reflect the balance between potentially positive feedbacks (increases in sea ice extent and enhanced primary productivity) and negative feedbacks (stronger southward heat transport and localized high-latitude warming). The Antarctic ice sheet had a complex, dynamic role in ocean circulation and heat fluxes during its initiation, and these processes are likely to operate in the future.


    Directory of Open Access Journals (Sweden)



    Full Text Available Penguins have peculiar modifications in their skeletal anatomy as a consequence of their extremely specialized diving habit. Morphological specialization is particularly evident in the forelimb. However, the kinematics of the pectoral girdle appears to be key to the locomotion of penguins. Penguin scapulae have an unusual morphology among birds. Modern penguins have a very large (especially broad scapula, whereas this bone is long but narrower in basal fossil species. The recent finding of an incomplete scapula with a singular acromion in the Upper Eocene Submeseta Allomember of the La Meseta Formation in the Antarctic Peninsula reveals a scapula proportionally narrower than those of modern penguins but similar to that of Waimanu and possibly other Eocene species. Osteological comparisons and muscular dissections of modern penguins show that the most striking feature is the curvature of the acromion, and the consequent enlargement of the facies articularis clavicularis. The configuration of the acromion and the corpus scapula reflects a lack of functional optimization in terms of the resistance to forces transverse to the body axis. The scapula´s general morphology suggests it belonged to a medium to large-sized penguin species with no so specialized diving skills. 

  2. Mineralogy and geochemistry of xenoliths in the Eocene volcanic rocks from southwest of Jandaq

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    Samineh Rajabi


    Full Text Available The Eocene volcanic rocks from the southwest of the Jandaq (Kuh-e-Godar-e-Siah, Central-East Iran micro-continent are andesitic basalt and andesite in composition. These rocks contain xenoliths with granulitic mineralogy. Mineral assemblage of these xenoliths is plagioclase + phlogopite + corundum + sillimanite + chlorite + phengite with granublastic, poiklioblastic and foliated textures in the pick metamorphic condition. Thermometry of phlogopite in these xenoliths suggests the average temperature 782oC. The characteristics of the xenoliths are consistent with the granolitic facies metamorphism of the Al-saturated Si-undersaturated crustal sediments at the lower crust condition. Melting of these granulites forms the magma which crystallized the S-type granitoids. Differentiation and crystallization of this magma causes the S-type granite formation. Therefore, the S-type granites in the study area are probably generated from melting of the granulites parts of which brought to the surface as xenoliths by Eocene magmatism in south of the Jandaq (Kuh-e-Godar-e-Siah. S-type granites in the study area are located along the Doruneh, Chupanan and Aeirakan faults in the Aeirakan area and Jandaq ophiolite. These granites are the source of uranium, thorium and uranium ore in southwest of the Aeirakan mountain.

  3. Eocene spiculites and spongolites in southwestern Australia: Not deep, not polar, but shallow and warm (United States)

    Gammon, Paul R.; James, Noel P.; Pisera, Andrjez


    Siliceous spongolite and spiculite are generally interpreted as deep- and/or cold-water deposits, largely because modern analogs are found mostly in cold- and/or deep-water environments. However, extensive shallow-water, biosiliceous accumulations are present in late Eocene age deposits of southern Western Australia. The attributes and paleoenvironmental setting of these accumulations frame the specific climatic and/or oceanographic constraints that allow such shallow neritic sediments to form. The generally fine grained siliciclastic-biosiliceous sediments accumulated in a nearshore, shallow-water setting, around numerous islands, and offshore from a warm-temperate, rainforest-covered upland. Sponges compose a lithistid-hexactinellid assemblage of Mesozoic Tethyan affinity, confined to deep water in the modern ocean, that migrated into neritic paleoenvironments during late Eocene time. Lithistids dominated shoreface environments and were reworked into sponge-conglomerate beaches, while hexactinellids flourished offshore in muddy subshoreface environments. These deposits also contain common soft demosponge spicules, and a rare but otherwise normal marine calcareous biota. The biosiliceous sediments grade offshore into bryozoan-rich marls and limestones. Sponges outcompeted the calcareous benthos in these inner shelf environments because of elevated amounts of land-derived nutrients that included high dissolved silica and a calm hydrodynamic setting. These deposits suggest that neither temperature nor water depth are critical factors for prolific sponge colonization. The rarity of such deposits in the rock record likely reflects the necessity for the coincidence of all of these factors, or they are misinterpreted.

  4. Analysis of systematic fracturing in Eocene flsch of the Slovenian coastal region

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    Marko Vrabec


    Full Text Available We analyse systematic fractures occurring in sandstone beds in Eocene flsch of the Slovenian coastal area. Two nearly perpendicular fracture sets were identifid: fractures F1 are generally NW-SE oriented, wellexpressed and predominately planar, whereas fractures F2 are NE-SW-striking, shorter, more irregular in shape, and terminate against the F1 set. The average orientation of both sets does not change signifiantly in a coastal transect crossing all principal structural domains of the area. We analysed fracture spacing with respect to layer thickness and determined fracture spacing index for both fracture sets. We interpret both fracture sets as tensional (Mode I joints originating in two distinct extensional episodes. Set F1 is older and formed in NE-SW directed tension which we correlate with the well-documented regional post-Dinaric orogen-perpendicular extension of presumably mid-Miocene age. Set F2 formed in NW-SE oriented tension, which is compatible with previously documented NE-SW-striking normal faults occurring in the area, but was so far not documented elsewhere. We interpret that F1 fractures predate folding and thrusting in the coastal belt. Earlier, Eocene-Oligocene Dinaric thrusting therefore did not signifiantly affect the coastal area, whereas post-F1 shortening, associated with northward indentation and underthrusting of the Adria microplate, did not commence before late Miocene.

  5. Anatomically preserved seeds of Nuphar (Nymphaeaceae) from the Early Eocene of Wutu, Shandong Province, China. (United States)

    Chen, Iju; Manchester, Steven R; Chen, Zhiduan


    Well-preserved seeds from the early Eocene of Wutu, Shandong, China are assigned to the genus Nuphar (Nymphaeaceae) based on morphology and anatomy. The seeds of Nuphar wutuensis sp. nov. are ellipsoidal to ovoid, 4-5 mm long with a clearly visible raphe ridge, and a truncate apex capped by a circular operculum ca. 1 mm in diameter bearing a central micropylar protrusion. These features, along with the testa composed of a uniseriate outer layer of equiaxial pentagonal to hexagonal surface cells and a middle layer 4-6 cells thick composed of thick-walled, periclinally elongate sclereids, correspond to the morphology and anatomy of extant Nuphar and distinguish this fossil species from all other extant and extinct genera of Nymphaeales. These seeds provide the oldest record for the genus in Asia and are supplemented by a similar well-preserved specimen from the Paleocene of North Dakota, USA. These data, together with the prior recognition of Brasenia (Cabombaceae) in the middle Eocene, indicate that the families Nymphaeaceae and Cabombaceae had differentiated by the early Tertiary.

  6. Early Eocene Molluscan biostratigraphy, Mount Pinos-Lockwood Valley area, northern Ventura County, southern California

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    Squires, R.L.; Wilson, M.


    A 600-m thick unnamed marine, predominantly transition-zone siltstone unit along the south flank of the Mount Pinos uplift, in the northern Lockwood Valley area, previously has been suggested to be early Eocene (Capay Stage) in age at its base. This present study shows the entire unit to be this age. Unconformably overlying the pre-Tertiary granite basement is 30 m of unfossiliferous muddy siltstone that grades upward into 50 m of very fine sandstone with rarely fossiliferous lenses of medium to coarse sandstone. Gradationally above the sandstone is 100 m of muddy siltstone with less rarely fossiliferous lenses of conglomeratic sandstone. Macrofossil collections made at 10 localities in these lower 180 m yielded a sparse fauna of subtropical shallow-marine gastropods and bivalves, as well as rare specimens of discocyclinid foraminifera. from 180 to 500 m above the base of the section is unfossiliferous siltstone with local occurrences of lower shoreface, alternating laminated and bioturbated very fine sandstone. The uppermost 100 m of the section is siltstone with rarely fossiliferous lenses of fine to medium sandstone. Collections made at five localities yielded subtropical shallow-marine mollusks. Evidence of a West Coast provincial molluscan Capay Stage (early Eocene) age for all the fossiliferous beds of the siltstone unit is the presence of Turritella andersoni, a species diagnostic of this stage. Commonly associated mollusks are Cryptoconus cooperi, Cylichnina tantilla, Ectinochilus (Macilentos) macilentus, and Turritella buwaldana. Unconformably overlying the unit is the Oligocene-lower Miocene nonmarine Plush Ranch Formation.

  7. Description of a Well Preserved Fetus of the European Eocene Equoid Eurohippus messelensis.

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    Jens Lorenz Franzen

    Full Text Available The early Middle Eocene locality of Grube Messel, near Darmstadt (Germany, is famous for its complete vertebrate skeletons. The degree of preservation of soft tissues, such as body silhouettes, internal organs and gut contents, is frequently remarkable. The present specimen was analyzed for remnants of the reproductive system. Classic anatomy and osteology and high-resolution micro-x-ray were applied to describe the fetus of the European Eocene equoid Eurohippus messelensis. Scanning electronic microscopy (SEM was used for determination of soft tissue remnants. The fetus is the earliest and best-preserved fossil specimen of its kind. The postcranial fetal skeleton is almost complete and largely articulated, allowing the conclusion that the pregnant mare was in late gestation. The apparent intrauterine position of the fetus is normal for the phase of pregnancy. Death of mare and fetus were probably not related to problems associated with parturition. Soft tissue interpreted as the uteroplacenta and a broad uterine ligament are preserved due to bacterial activity and allow considerations on the evolutionary development of the structures.

  8. Subtropical Arctic Ocean temperatures during the Palaeocene/Eocene thermal maximum (United States)

    Sluijs, A.; Schouten, S.; Pagani, M.; Woltering, M.; Brinkhuis, H.; Damste, J.S.S.; Dickens, G.R.; Huber, M.; Reichart, G.-J.; Stein, R.; Matthiessen, J.; Lourens, L.J.; Pedentchouk, N.; Backman, J.; Moran, K.; Clemens, S.; Cronin, T.; Eynaud, F.; Gattacceca, J.; Jakobsson, M.; Jordan, R.; Kaminski, M.; King, J.; Koc, N.; Martinez, N.C.; McInroy, D.; Moore, T.C.; O'Regan, M.; Onodera, J.; Palike, H.; Rea, B.; Rio, D.; Sakamoto, T.; Smith, D.C.; St John, K.E.K.; Suto, I.; Suzuki, N.; Takahashi, K.; Watanabe, M. E.; Yamamoto, M.


    The Palaeocene/Eocene thermal maximum, ???55 million years ago, was a brief period of widespread, extreme climatic warming, that was associated with massive atmospheric greenhouse gas input. Although aspects of the resulting environmental changes are well documented at low latitudes, no data were available to quantify simultaneous changes in the Arctic region. Here we identify the Palaeocene/Eocene thermal maximum in a marine sedimentary sequence obtained during the Arctic Coring Expedition. We show that sea surface temperatures near the North Pole increased from ???18??C to over 23??C during this event. Such warm values imply the absence of ice and thus exclude the influence of ice-albedo feedbacks on this Arctic warming. At the same time, sea level rose while anoxic and euxinic conditions developed in the ocean's bottom waters and photic zone, respectively. Increasing temperature and sea level match expectations based on palaeoclimate model simulations, but the absolute polar temperatures that we derive before, during and after the event are more than 10??C warmer than those model-predicted. This suggests that higher-than-modern greenhouse gas concentrations must have operated in conjunction with other feedback mechanisms-perhaps polar stratospheric clouds or hurricane-induced ocean mixing-to amplify early Palaeogene polar temperatures. ?? 2006 Nature Publishing Group.

  9. Paleoelevation reconstruction of the Paleocene-Eocene Gonjo basin, SE-central Tibet (United States)

    Tang, Maoyun; Liu-Zeng, Jing; Hoke, Gregory D.; Xu, Qiang; Wang, Weitao; Li, Zhanfei; Zhang, Jinyu; Wang, Wei


    The topography evolution of the southeastern Tibetan Plateau provides a constraint for evaluating various geodynamic models of plateau formation. We reconstruct the Paleocene to Eocene paleoelevation of the Cenozoic Gonjo basin in the Qiangtang terrane, using oxygen and carbon stable isotopic results from pedogenic carbonates of the lower Ranmugou Formation. Lithofacies associations indicate that the lower Ranmugou Formation was deposited in alluvial fan and fluvial floodplain environments. U-Pb dating of volcanics within the middle Ranmugou Formation constrains the deposition of the lower Ranmugou Formation as prior to 43.2 Ma. Paleoelevations are calculated using both a thermodynamic model and an empirical relationship. The empirical relationship of elevation-δ18O is determined from a series of modern water samples. Calculated paleoelevations indicate that the Gonjo basin attained a minimum average elevation of 2100-2500 m in the early Eocene. Together with recent paleoaltimetry studies in the region, it can be concluded that the crust of southeastern Tibetan Plateau was already thickened by that time. The calculation is based on the section in northern Gonjo basin, where δ18O values of paleosol nodules appear to be unaltered, but we cannot rule out the possibility that δ18O values of the pedogenic carbonates had been partially reset. Our preliminary results favor tectonic models compatible with pre-Miocene uplift of the SE-central Tibetan Plateau.

  10. Paleocene/Eocene boundary changes in atmospheric and oceanic circulation: A Southern Hemisphere record (United States)

    Hovan, Steven A.; Rea, David K.


    Deep Sea Drilling Project (DSDP) Site 215 provides an expanded section across the Paleocene/Eocene boundary, the most complete mid-latitude sequence from a Southern Hemisphere location in the Indo-Pacific area. The events of this transition occurred during a span of about 1.2 m.y. Oxygen isotope values derived from benthic foraminiferal calcite decrease by about 1.0‰, a decrease most likely related to warming of deep ocean waters. Turnovers of benthic foraminifera accompany δ18O changes and culminate in the predominant extinction event at the end of the Paleocene Epoch. Carbon isotope ratios also shift dramatically toward lighter values near the end of the Paleocene, beginning about 0.45 m.y. after oxygen isotope values start to change. The intensity of Southern Hemisphere atmospheric circulation as recorded by grain sizes of eolian particles shows a large and rapid reduction beginning another 0.45 m.y. later. A significant reduction of zonal wind strength at the Paleocene/Eocene boundary, until now observed only at Northern Hemisphere locations, appears to have been a global phenomenon related to decreased latitudinal thermal gradients occasioned by more effective poleward heat transport via the deep ocean.


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    Full Text Available Original biostratigraphic and sedimentologic data concerning the type-section of the Albidona Formation (Liguride Complex, Southern Apennines, Italy are presented and discussed. Since its definition in 1962, this lithostratigraphic unit has been the object of controversial interpretations in terms of age attribution and paleotectonic significance. Based on cross-observations performed on calcareous nannofossils and palynomorphs, we conclude that the Albidona Formation must be assigned to the Eocene and, based on these evidences, we make a review of the previous biostratigraphic literature. We further recognise four different turbidite systems (named A to D, bounded by minor stratigraphic hiatuses, that are characterised by different sedimentary facies assemblages and petrofacies. The overall vertical arrangement demonstrates that the Albidona Formation was deposited in a tectonically mobile basin during a phase of deformation that is older than the apenninic deformation and must be likely referred to the alpine tectonics of the Calabrian arc. Moreover, the relationship with the underlying folded unit suggests for the Albidona Formation the significance of an episutural deposit relevant to a Paleogene deformation that affected the older units of the Liguride Complex. By considering stratigraphic and sedimentological features, we suggest a correlation of the Albidona Formation with analogue turbidite suites cropping out in the Apennines, discussing their significance in the context of the Eocene tectonic paroxysm in the Mediterranean area.

  12. Eocene Yegua Formation (Claiborne group) and Jackson group lignite deposits of Texas (United States)

    Hook, Robert W.; Warwick, Peter D.; Swanson, Sharon M.; Hackley, Paul C.; Warwick, Peter D.; Karlsen, Alexander K.; Merrill, Matthew D.; Valentine, Brett J.


    The lignite deposits within the upper Eocene Yegua Formation (Claiborne Group) and the overlying Jackson Group are among the coal resources that were not quantitatively assessed as part of the U.S. Geological Survey's (USGS) National Coal Resource Assessment (NCRA) program in the Gulf Coastal Plain coal province. In the past, these lignite-bearing stratigraphic units often have been evaluated together because of their geographic and stratigraphic proximity (Fisher, 1963; Kaiser, 1974; Kaiser et al., 1980; Jackson and Garner, 1982; Kaiser, 1996) (Figures 1, 2). The term “Yegua-Jackson trend“ is used informally herein for the lignite-bearing outcrops of these Late Eocene deposits in Texas. Lignite beds in the Yegua-Jackson trend generally are higher both in ash yield and sulfur content than those of the underlying Wilcox Group (Figure 2). Recent studies (Senkayi et al., 1987; Ruppert et al., 1994; Warwick et al., 1996, 1997) have shown that some lignite beds within the Yegua-Jackson trend contain partings of volcanic ash and host elevated levels of trace elements that have been identified as potentially hazardous air pollutants (HAPs) in the United States Clean Air Amendments of 1990. Lignite beds within the Yegua Formation are thin (less than or equal to 6 ft) and laterally discontinuous in comparison with most Wilcox Group deposits (Ayers, 1989a); in contrast, the Jackson Group lignite beds range up to 12 ft in total thickness and are relatively continuous laterally, extending nearly 32 mi along strike.

  13. Geological evolution of Eocene Aǧrı Basin (Eastern Anatolia-Turkey): Preliminary results (United States)

    Fırat Demirkaya, Demirkan; Aksoy, Necmettin; Üner, Serkan


    Continental collision zones are sites of intense crustal deformation resulting in different geological processes such as crustal thickening, regional contraction, and volcanic activity. The East Anatolian Plateau emerges from the compression and following collision between the Eurasian and Arabian plates. Numerous basins were formed by this compressional tectonism, including the Pasinler, Muş, and Lake Van basins. The E-W trending Aǧrı Basin is located at north of the collision zone formed by compressional tectonism in Eocene and shaped by the volcanism that was active since Miocene. The basins fill initiates with Middle Eocene to Lower Miocene shallow marine deposits composing of reefal limestones, mudstones, and sandstones. Ongoing compressional regime and related regional uplift caused regression and latter transition from shallow marine to terrestrial environments in Middle Miocene took place. Marine units are unconformably overlain by Upper Miocene to Pliocene lacustrine and fluvial deposits. The Quaternary sedimentation is represented by alluvial fan deposits derived from the northern margin of the basin and young fluvial sediments. Volcanic and volcanoclastic products are frequently observed in Miocene to Recent basin deposits. Currently, E-W trending thrust faults, forming the Aǧrı Basin, continue to control the shape and depositional processes of the basin. Deformation of alluvial fans and channel shifting of the Murat and Seryan rivers which longitudinally passing the basin are the prominent geomorphological indicators of this tectonic activity.

  14. Astronomically paced middle Eocene deepwater circulation in the western North Atlantic (United States)

    Vahlenkamp, Maximilian; Niezgodzki, Igor; De Vleeschouwer, David; Bickert, Torsten; Harper, Dustin; Lohmann, Gerrit; Pälike, Heiko; Zachos, James C.


    The role of the Atlantic Meridional Overturning Circulation (AMOC) as a key player for abrupt climatic changes (e.g. Heinrich Stadials) during the Pleistocene is relatively well constrained. However, the timing of the onset of a „modern" North Atlantic Deepwater (NADW) formation are still debated: Recent estimates range from the middle Miocene to the Early Eocene [Davies et al., 2001, Stoker et al., 2005, Hohbein et al., 2012] and are mainly based on the seismic interpretation contourite drifts. Another understudied aspect of the AMOC is its behavior during climatic variations on orbital time scales and under different climatic boundary conditions (icehouse vs hothouse). IODP Expedition 342 drilled carbonate-rich sequences from sediment drifts offshore Newfoundland that cover the middle Eocene with high sedimentation rates ( 3 cm/ kyr). We present a 2 Myr long stable carbon and oxygen isotope record of benthic foraminifera nuttalides truempyi spanning magnetochron C20r in unprecedented resolution (Nielsen, T., and Shannon, P. M., 2005, Neogene stratigraphy and the sedimentary and oceanographic development of the NW European Atlantic margin: Marine and Petroleum Geology, v. 22, no. 9, p. 977-1005. Hohbein, M. W., Sexton, P. F., and Cartwright, J. A., 2012, Onset of North Atlantic Deep Water production coincident with inception of the Cenozoic global cooling trend: Geology, v. 40, no. 3, p. 255-258.

  15. Climatic changes in the Antarctic Eocene: - palaeontological, mineralogical and geochemical fossil proxies from bryozoans (United States)

    Hara, Urszula


    The earliest Antarctic Cenozoic (late early Eocene) bryozoan fossil records, recognized in the La Meseta Fm. on Seymour Island (Antarctic Peninsula) are connected with the major K/T phase of the cheilostome evolution, clear preponderance of cerioporoidean cyclostomes along with abundant occurrence of microporoideans, umbonulomorphs and lepraliomorphs. The presence of the loose, small zooecia of the cheilostome bryozoans in the lowermost part of this formation, systematically includes the buguloids and catenicelloideans such as e.g. Beanidae, Catenicellidae, Savignyellidae and Calwelliidae families, which in the present day are widely distributed in the tropical-warm latitudes mostly in the shallow-marine settings (Hara 2015). Undoubtedly, the occurrence of over 90% of the warm-loving multilamellar cyclostomes with the relatively slow growing rate is connected with a short-term episode in the lower part of the La Meseta Formation (Telm1), during their long in situ evolution. The recently recognized biota in the middle part of the La Meseta Formation (Telm4 and Telm5) on the NE side of the Seymour Island, reveal a presence of the microporoideans of the Micropora as well as free-living lunulitiforms belonging to the Lunulites and Otionellina genera, which developed disc-shaped colonies (Hara et al. 2015, in review). They are dominated in the Telm5, along with the new umbonulomorph of the family Brydonellidae Uharella seymourensis, found as an epilithozoic, encrusting bryozoan occurring in a loose residuum of the siliciclastic sediments. Environmentally, Recent, free-living lunulitids are known to occur in warm, shallow-shelf conditions, at temperatures of 10-29˚C, on coarse, sandy to muddy bottom with low to moderate deposition in fairly high velocity current regime and they are overwhelmingly associated with sand fauna environments. The dominance of the lunulitiform colonies in the Telm4-5 may suggests the shallow-water setting in this middle part of the formation

  16. Environmental impact and magnitude of paleosol carbonate carbon isotope excursions marking five early Eocene hyperthermals in the Bighorn Basin, Wyoming

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    Abels, H.A.; Lauretano, V.; van Yperen, Anna E.; Hopman, Tarek; Zachos, J.C.; Lourens, L.J.; Gingerich, P.D.; Bowen, G.J.


    Transient greenhouse warming events in the Paleocene and Eocene were associated with the addition of isotopically light carbon to the exogenic atmosphere–ocean carbon system, leading to substantial environmental and biotic change. The magnitude of an accompanying carbon isotope excursion (CIE) can

  17. Reconstruction of the Arctic Ocean environment during the Eocene Azolla interval using geochemical proxies and climate modeling. Geologica Ultraiectina (331)

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    Speelman, E.N.


    With the realization that the Arctic Ocean was covered with enormous quantities of the aquatic floating fern Azolla 49 Myrs ago, new questions regarding the Eocene conditions facilitating these blooms arose. This dissertation describes the reconstruction of paleo-environmental conditions

  18. Trace fossils from the eocene Lillebælt clay formation, Røsnæs Peninsula, Denmark

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    Nielsen, Jan Kresten; Milàn, Jesper; Mesfun, Daniel


    A cliff exposure of the Eocene Lillebælt Clay Formation, on the Røsnæs peninsula of Zealand, Denmark, has yielded a diverse trace-fossil assemblage. The trace fossils are described formally for the first time and assigned to Phymatoderma melvillensis, unnamed clusters of small burrows, Ophiomorph...

  19. Magnetostratigraphy and Tectonic Rotation of the Eocene-Oligocene Makah and Hoko River Formations, Northwest Washington, USA

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    Donald R. Prothero


    Full Text Available The Eocene-Oligocene Makah Formation and subjacent middle Eocene Hoko River Formation of the northwestern Olympic Peninsula, Washington, yield mollusks, crustaceans, foraminifera, and early neocete whales; their age has never been precisely established. We sampled several sections; most samples showed a stable single-component remanence held largely in magnetite and passed a Class I reversal test. The upper Refugian (late Eocene and lower Zemorrian (early Oligocene rocks at Baada Point correlate with Chron C13r (33.7–34.7 Ma and Chron C12r (30–33 Ma. The Ozette Highway section of the Makah Formation spanned the early Refugian to late Refugian, with a sequence that correlates with Chrons C15r-C13r (33.7–35.3 Ma, and a long reversed early Zemorrian section that correlates with Chron C12r (30–33 Ma. The type section of the Hoko River Formation correlates with Chron C18r (40.0–41.2 Ma. The area sampled shows about 45∘ of post-Oligocene counterclockwise tectonic rotation, consistent with results obtained from the Eocene-Oligocene rocks in the region.

  20. Multiproxy record of abrupt sea-surface cooling across the Eocene-Oligocene transition in the Gulf of Mexico

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    Wade, B.S.; Houben, A.J.P.; Quaijtaal, W.; Schouten, S.; Rosenthal, Y.; Miller, K.G.; Katz, M.E.; Wright, J.D.; Brinkhuis, H.


    The Eocene-Oligocene transition (EOT; ca. 33–34 Ma) was a time of pronounced climatic change, marked by the establishment of continental-scale Antarctic ice sheets. The timing and extent of temperature change associated with the EOT is controversial. Here we present multiproxy EOT climate records

  1. Primates as Predictors of Mammal Community Diversity in the Forest Ecosystems of Madagascar (United States)

    Muldoon, Kathleen M.; Goodman, Steven M.


    The geographic distribution of species is the typical metric for identifying priority areas for conservation. Since most biodiversity remains poorly studied, a subset of charismatic species, such as primates, often stand as surrogates for total biodiversity. A central question is therefore, how effectively do primates predict the pooled species richness of other mammalian taxa? We used lemurs as indicator species to predict total non-primate mammal community richness in the forest ecosystems of Madagascar. We combine environmental and species occurrence data to ascertain the extent to which primate diversity can predict (1) non-primate mammal α-diversity (species richness), (2) non-primate complementarity, and (3) non-primate β-diversity (species turnover). Our results indicate that primates are effective predictors of non-primate mammal community diversity in the forest ecosystems of Madagascar after controlling for habitat. When individual orders of mammals are considered, lemurs effectively predict the species richness of carnivorans and rodents (but not afrosoricids), complementarity of rodents (but not carnivorans or afrosoricids), and all individual components of β-diversity. We conclude that lemurs effectively predict total non-primate community richness. However, surrogate species alone cannot achieve complete representation of biodiversity. PMID:26334525

  2. The Eocene Arctic Azolla phenomenon: species composition, temporal range and geographic extent. (United States)

    Collinson, Margaret; Barke, Judith; van der Burgh, Johan; van Konijnenburg-van Cittert, Johanna; Pearce, Martin; Bujak, Jonathan; Brinkhuis, Henk


    Azolla is a free-floating freshwater fern that is renowned for its rapid vegetative spread and invasive biology, being one of the world's fastest growing aquatic macrophytes. Two species of this plant have been shown to have bloomed and reproduced in enormous numbers in the latest Early to earliest Middle Eocene of the Arctic Ocean and North Sea based on samples from IODP cores from the Lomonosov Ridge (Arctic) and from outcrops in Denmark (Collinson et al 2009 a,b Review of Palaeobotany and Palynology 155,1-14; and doi:10.1016/j.revpalbo.2009.12.001). To determine the geographic and temporal extent of this Azolla phenomenon, and the spatial distribution of the different species, we have examined samples from 15 additional sites using material from ODP cores and commercial exploration wells. The sites range from the Sub-Arctic (Northern Alaska and Canadian Beaufort Mackenzie Basin) to the Nordic Seas (Norwegian-Greenland Sea and North Sea Basin). Our data show that the Azolla phenomenon involved at least three species. These are distinguished by characters of the megaspore apparatus (e.g. megaspore wall, floats, filosum) and the microspore massulae (e.g. glochidia fluke tips). The Lomonosov Ridge (Arctic) and Danish occurrences are monotypic but in other sites more than one species co-existed. The attachment to one another and the co-occurrence of megaspore apparatus and microspore massulae, combined with evidence that these spores were shed at the fully mature stage of their life cycle, shows that the Azolla remains were not transported over long distances, a fact which could not be assumed from isolated massula fragments alone. Our evidence, therefore, shows that Azolla plants grew on the ocean surfaces for approximately 1.2 million years (from 49.3 to 48.1 Ma) and that the Azolla phenomenon covered the area from Denmark northwards across the North Sea Basin and the whole of the Arctic and Nordic seas. Apparently, early Middle Eocene Northern Hemisphere middle

  3. Deep-sea Benthic Foraminifera in the SE Atlantic across Eocene Hyperthermal Events (United States)

    Thomas, E.


    Short-term episodes of global warming (hyperthermal events) were superimposed on the warming trend into the Early Eocene Climate Optimum (EECO). The Paleocene-Eocene Thermal Maximum (PETM; 56 Ma) was the most extreme, followed by Eocene Thermal Maximum-2 and -3 (ETM2: 1.8 myr, ETM3: 3.1 myr post-PETM). Hyperthermals are characterized by negative carbon isotope excursions (CIEs, emission of isotopically light carbon in the ocean-atmosphere), negative oxygen isotope excursions (global warming) and carbonate dissolution (ocean acidification). Sensitivity of biota to environmental changes due to carbon emissions can be evaluated by studying their response to hyperthermals of different magnitude. Deep-sea benthic foraminiferal records across PETM, ETM2 and -3 are available for Site 1262 (3600 m) and 1263 (1500m) on SE Atlantic Walvis Ridge. Benthic foraminifera (carbonate and agglutinated) are absent in the carbonate-free PETM clay-layer (Site 1262: 65 kyr; Site1263: 10 kyr). Deep-sea benthic foraminifera suffered extinction and diversity loss at the start of the PETM, as they did globally, with diversity recovering only partially. Stable isotope records show a larger PETM-CIE and amount of warming at Site 1263 than global average (McCarren et al., 2008), and warming was more pronounced at Site 1263 than at 1262 during ETM2 (Jennions et al., 2015) and ETM3 (Roehl et al., 2005). During ETM2 and -3, carbonate dissolution affected the sites, both remaining between CCD and lysocline. Assemblages were more severely affected (larger drop in benthic foraminiferal accumulation rates, BFAR) at the shallower site, opposite to expected if caused mainly by carbonate corrosivity. The large decrease in BFAR indicates a decline in food arrival at the sea floor, more pronounced at the shallower site, as supported by changes in relative and absolute abundance of species, and more pronounced at ETM2 than at ETM3. Greater warming at intermediate depths could have been caused by ocean

  4. Early Eocene carbon isotope excursions and landscape destabilization at eccentricity minima: Green River Formation of Wyoming (United States)

    Smith, M. Elliot; Carroll, Alan R.; Scott, Jennifer J.; Singer, Brad S.


    Repeated global reorganizations of carbon cycling and biotic, oceanic and terrestrial processes occurred during the Early Eocene, and appear to have been paced by cyclic variations in the eccentricity of the Earth's orbit. The phase relationship(s) between insolation variation, terrestrial paleoclimate, and atmospheric pCO2 during these events remains enigmatic however, due to their poorly constrained timing relative to specific orbital configurations. Here we use tiered interpolation between radioisotopic ages and paleomagnetic polarity chrons to compare high-resolution δ13C and lithofacies records from the Wilkins Peak Member of the Green River Formation of western North America to a Fe-intensity XRF record from the western Atlantic Ocean, and to numerical solutions for Earth's orbital configuration. Wilkins Peak Member lithofacies stacking patterns record cyclic geomorphic responses to insolation and climate fluctuations, spanning an interval of 1.8 Ma. Previous macrostratigraphic analyses using 40Ar/39Ar and U-Pb ash bed ages indicate that these cycles reflect long and short eccentricity modulation of precession. Hydrologic variance appears to have occurred inversely with intervals of maximum sediment advection, with carbonate- and evaporite-dominated lacustrine modes during eccentricity maxima, and siliciclastic-dominated alluvial modes during eccentricity minima. Stable carbon isotope analyses of 126 meters of Wilkins Peak Member strata reveal a regular ∼5 per mil oscillation between high-δ13C lacustrine modes and low-δ13C alluvial modes. Tiered interpolation between paleomagnetically characterized terrestrial ash beds facilitates the integration of 11 radioisotopic ages with the geomagnetic polarity timescale, resulting in significant expansion of chron C23 and shortening of chron C22 relative to timescales based on seafloor magnetic anomaly profiles. The new proposed timescale permits direct comparison of terrestrial and marine climate proxy records

  5. The Rajang Unconformity: Major provenance change between the Eocene and Miocene sequences in NW Borneo (United States)

    Breitfeld, H. T.; Hennig, J.; BouDagher-Fadel, M.; Hall, R.


    The offshore Sarawak Basin NW of North Sarawak is a major hydrocarbon province in SE Asia. A very thick sedimentary sequence of Oligocene to ?Early Miocene age, named Cycle 1, is an important hydrocarbon source and reservoir. Despite numerous wells the stratigraphy and tectonic history is not very well understood. The Nyalau Formation of onshore North Sarawak is the supposed equivalent of the offshore Cycle 1 sequence. The Nyalau Formation is a thick sedimentary sequence of mainly tidal to deltaic deposits. The formation is dominated by well-bedded sandstone-mudstone alternations and thicker sandstones with abundant bioturbation. The sandstones are predominantly arenaceous. Various lithic fragments and feldspar indicate multiple sources and fresh input from igneous and metamorphic rocks. Interbedded thin limestone beds and marls yielded Early Miocene foraminifera for the upper part of the succession. Zircons separated from the sandstones yielded mainly Cretaceous and Triassic ages. The Triassic is the dominant age population. The Nyalau Formation conformably overlies the Buan Shale and the Tatau Formation, and in places unconformably overlies the Belaga Formation. The Belaga Formation is part of the Rajang Group that represents remnants of a large submarine fan deposited in the Late Cretaceous to Eocene in Central Sarawak. In contrast to the Nyalau Formation, the majority of zircons from the Rajang Group have Cretaceous ages. This marks an important change in provenance at the major unconformity separating the Belaga and Nyalau Formations. This unconformity was previously interpreted as the result of an orogeny in the Late Eocene. However, there is no evidence for a subduction or collision event at this time in Sarawak. We interpret it to mark plate reorganisation in the Middle Eocene and name it the Rajang Unconformity. Borneo is the principal source of Cretaceous zircons which were derived from the Schwaner Mountains and West Sarawak. The dominant Triassic zircon

  6. Climate change likely to favor shift toward warmer climate states of the Pliocene and Eocene (United States)

    Burke, K. D.; Williams, J. W.


    As the world warms due to rising greenhouse gas concentrations, the climate system is moving toward a state without precedent in the historical record. Various past climate states have been proposed as potential analogues or model systems for the coming decades, including the early to middle Holocene, the last interglacial, the middle Pliocene, and the early Eocene. However, until now, such comparisons have been qualitative. To compare these time periods to the projected climate states for the 21st and 22nd centuries, we conduct a climate similarity analysis using the standardized Euclidean distance metric (SED) and seasonal means of surface air temperature and precipitation. We make this future-to-past comparison using 30-year mean climatologies, for every decade between 2020 and 2280 AD (27 total comparisons). The list of past earth system states includes the historical period (1940-1970 AD), a pre-industrial control (ca. 1850), the middle Holocene (ca. 6 ka), the last glacial maximum (ca. 21 ka), the last interglacial (ca. 125 ka), the middle Pliocene (ca. 3 Ma), and the early Eocene (ca. 50-55 Ma). To reduce uncertainties resulting from choice of earth system model, analyses are based on simulations from three earth system models (HadCM, CCSM, NASA/GISS Model-E), using in part experiments from PMIP2, PMIP3/CMIP5, EoMIP, and PlioMIP. Results are presented for two representative concentration pathways (RCP's 4.5, 8.5). By 2050 AD, the most common past climate analogue is sourced from the Pliocene for RCP 8.5, while by 2190 AD, the Eocene becomes the source of the most common past climate analogue. For RCP 4.5, in which radiative forcings stabilize this century, the Pliocene becomes the most important past climate analogue by 2100 AD. Low latitude climates are the first to most closely resemble these past earth warm periods. The mid-latitudes then follow this pattern by the end of the 22nd century. Although no past state of the earth system is a perfect analogue

  7. Palynological Response to Middle Eocene Climate Variability in the North Atlantic Ocean: IODP Expedition 342, Newfoundland Ridge, Offshore Canada (United States)

    Willard, D. A.


    Proxy records from Eocene hyperthermals provide evidence for rates and magnitudes of environmental changes associated with these events, as well as their impacts on terrestrial and marine ecosystems. The Middle Eocene Climatic Optimum (MECO) occurred ~40 Million years ago (Ma) and lasted ~500,000 years, and previous research has documented changes in marine and terrestrial biotas during and after this event. Cores collected in sediment drifts on Newfoundland Ridge off the coast of eastern Canada during IODP Expedition 342 recovered expanded sections of the middle Eocene, with sedimentation rates of 1-2 cm/kyr. We present results from pollen, palynofacies, and dinocyst analyses from Sites 1408 (41.438'N, 49.786'W, 3022 mwd), 1409 (41.296'N, 49.233'W, 3501 mwd), and 1410 (41.328'N, 49.170'W, 3387 mwd), spanning an interval that includes the MECO. Palynological assemblages are well preserved throughout the middle Eocene at Sites 1408 and 1410, whereas carbonate-rich samples from Site 1409 were completely barren of palynomorphs. Substantial variability in dinocyst species composition and diversity, pollen assemblages, and organic palynofacies were observed within the MECO event. Fluctuations in concentrations of opaque organic matter, insect fragments, and pollen and spores from terrestrial vegetation reflect changes in terrigenous influx, intensity of the hydrologic cycle, and source vegetation. Dinocyst assemblage shifts are correlated with changes in productivity, nutrient supply, and salinity. Integration of palynological data with other proxies will provide further insights into correlations between increased terrigenous input and eutrophication, leads and lags between terrestrial and marine responses to climate fluctuations, and environmental stability during the Middle Eocene.

  8. Eocene tectonic compression in Northern Zealandia: Magneto-biostratigraphic constraints from the sedimentary records of New Caledonia (Southwest Pacific Ocean) (United States)

    Dallanave, E.; Agnini, C.; Pascher, K. M.; Maurizot, P.; Bachtadse, V.; Hollis, C. J.; Dickens, G. R.; Collot, J.; Sevin, B.; Strogen, D.; Monesi, E.


    Published seismic profiles acquired from the Tasman Sea and northern Zealandia area (southwest Pacific) point to a widespread Eocene convergent deformation of oceanic and continental crust, with reverse faults and uplift (Tectonic Event of the Cenozoic in the Tasman Area; TECTA). The TECTA is interpreted as the precursor of the Tonga-Kermadec subduction initiation. Grande Terre is the main island of the New Caledonia archipelago and the largest emergent portion of northern Norfolk Ridge (part of northern Zealandia). Eocene sedimentary records exposed in Grande Terre contain a transition from pelagic micrite to terrigenous-rich calciturbidites, marking a shift from passive margin to convergent tectonic regime. This could represent the local expression of the convergence inception observed on a regional scale. We conducted an integrated magneto-biostratigraphic study, based on calcareous nannofossil and radiolaria, of two early-middle Eocene records cropping out near Noumea (southwest Grande Terre) and Koumac (northwest Grande Terre). The natural remanent magnetization of the sediments is complicated by multiple vector components, likely related to the late Eocene obduction, but a characteristic remanent magnetization has been successfully isolated. Overall the record spans from magnetic polarity Chron C23n to C18n, i.e. from 51 to 39 Ma. In this robust magnetic polarity-based chronological frame, the pelagic micrite to terrigenous-rich calciturbidites occurred near the top of Chron C21n and is dated 46 Ma. Furthermore, the magnetic mineral assemblage within part of the calciturbidites consists of hematite associated with maghemite. This association indicates emergent land as source of the terrigenous, suggesting a considerable uplift. Because 94% of the Zealandia continent is submerged, ocean drilling is needed to gauge the full extent and timing of Eocene compressive deformation revealed by the seismic profiles acquired in the Tasman area. This is a primary aim of

  9. Non-Human Primate Models of Orthopoxvirus Infections

    Directory of Open Access Journals (Sweden)

    Anne Schmitt


    Full Text Available Smallpox, one of the most destructive diseases, has been successfully eradicated through a worldwide vaccination campaign. Since immunization programs have been stopped, the number of people with vaccinia virus induced immunity is declining. This leads to an increase in orthopoxvirus (OPXV infections in humans, as well as in animals. Additionally, potential abuse of Variola virus (VARV, the causative agent of smallpox, or monkeypox virus, as agents of bioterrorism, has renewed interest in development of antiviral therapeutics and of safer vaccines. Due to its high risk potential, research with VARV is restricted to two laboratories worldwide. Therefore, numerous animal models of other OPXV infections have been developed in the last decades. Non-human primates are especially suitable due to their close relationship to humans. This article provides a review about on non-human primate models of orthopoxvirus infections.

  10. Cocaine is pharmacologically active in the nonhuman primate fetal brain

    DEFF Research Database (Denmark)

    Benveniste, Helene; Fowler, Joanna S; Rooney, William D


    Cocaine use during pregnancy is deleterious to the newborn child, in part via its disruption of placental blood flow. However, the extent to which cocaine can affect the function of the fetal primate brain is still an unresolved question. Here we used PET and MRI and show that in third......-trimester pregnant nonhuman primates, cocaine at doses typically used by drug abusers significantly increased brain glucose metabolism to the same extent in the mother as in the fetus (approximately 100%). Inasmuch as brain glucose metabolism is a sensitive marker of brain function, the current findings provide...... evidence that cocaine use by a pregnant mother will also affect the function of the fetal brain. We are also unique in showing that cocaine's effects in brain glucose metabolism differed in pregnant (increased) and nonpregnant (decreased) animals, which suggests that the psychoactive effects of cocaine...

  11. Social manipulation in nonhuman primates: Cognitive and motivational determinants. (United States)

    Völter, C J; Rossano, F; Call, J


    Social interactions are the result of individuals' cooperative and competitive tendencies expressed over an extended period of time. Although social manipulation, i.e., using another individual to achieve one's own goals, is a crucial aspect of social interactions, there has been no comprehensive attempt to differentiate its various types and to map its cognitive and motivational determinants. For this purpose, we survey in this article the experimental literature on social interactions in nonhuman primates. We take social manipulation, illustrated by a case study with orangutans (Pongo abelii), as our starting point and move in two directions. First, we will focus on a flexibility/sociality axis that includes technical problem solving, social tool-use and communication. Second, we will focus on a motivational/prosociality axis that includes exploitation, cooperation, and helping. Combined, the two axes offer a way to capture a broad range of social interactions performed by human and nonhuman primates. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Justice- and fairness-related behaviors in nonhuman primates. (United States)

    Brosnan, Sarah F


    A distinctive feature across human societies is our interest in justice and fairness. People will sometimes invest in extremely costly behavior to achieve fair outcomes for themselves and others. Why do people care so much about justice? One way to address this is comparatively, exploring behaviors related to justice and fairness in other species. In this paper, I review work exploring responses to inequity, prosocial behavior, and other relevant behaviors in nonhuman primates in an effort to understand both the potential evolutionary function of these behaviors and the social and ecological reasons for the individual differences in behavior. I also consider how these behaviors relate to human behavior, particularly in the case of experimental studies using games derived from experimental economics to compare nonhuman primates' responses to those of humans in similar experimental conditions. These results emphasize the importance of a comparative approach to better understand the function and diversity of human behavior.

  13. DRD4 dopamine receptor allelic diversity in various primate species

    Energy Technology Data Exchange (ETDEWEB)

    Adamson, M.; Higley, D. [NIAAA, Rockville, MD (United States); O`Brien, S. [NCI, Frederick, MD (United States)] [and others


    The DRD4 dopamine receptor is uniquely characterized by a 48 bp repeating segment within the coding region, located in exon III. Different DRD4 alleles are produced by the presence of additional 48 bp repeats, each of which adds 16 amino acids to the length of the 3rd intracytoplasmic loop of the receptor. The DRD4 receptor is therefore an intriguing candidate gene for behaviors which are influenced by dopamine function. In several human populations, DRD4 alleles with 2-8 and 10 repeats have previously been identified, and the 4 and 7 repeat alleles are the most abundant. We have determined DRD4 genotypes in the following nonhuman primate species: chimpanzee N=2, pygmy chimpanzee N=2, gorilla N=4, siamang N=2, Gelada baboon N=1, gibbon N=1, orangutan (Bornean and Sumatran) N=62, spider monkey N=4, owl monkey N=1, Colobus monkey N=1, Patas monkey N=1, ruffed lemur N=1, rhesus macaque N=8, and vervet monkey N=28. The degree of DRD4 polymorphism and which DRD4 alleles were present both showed considerable variation across primate species. In contrast to the human, rhesus macaque monkeys were monomorphic. The 4 and 7 repeat allels, highly abundant in the human, may not be present in certain other primates. For example, the four spider monkeys we studied showed the 7, 8 and 9 repeat length alleles and the only gibbon we analyzed was homozygous for the 9 repeat allele (thus far not observed in the human). Genotyping of other primate species and sequencing of the individual DRD4 repeat alleles in different species may help us determine the ancestral DRD4 repeat length and identify connections between DRD4 genotype and phenotype.

  14. Responses of primate frontal cortex neurons during natural vocal communication


    Miller, Cory T.; Thomas, A. Wren; Nummela, Samuel U.; de la Mothe, Lisa A.


    The role of primate frontal cortex in vocal communication and its significance in language evolution have a controversial history. While evidence indicates that vocalization processing occurs in ventrolateral prefrontal cortex neurons, vocal-motor activity has been conjectured to be primarily subcortical and suggestive of a distinctly different neural architecture from humans. Direct evidence of neural activity during natural vocal communication is limited, as previous studies were performed ...

  15. A metagenomic study of primate insect diet diversity. (United States)

    Pickett, Sarah B; Bergey, Christina M; Di Fiore, Anthony


    Descriptions of primate diets are generally based on either direct observation of foraging behavior, morphological classification of food remains from feces, or analysis of the stomach contents of deceased individuals. Some diet items (e.g. insect prey), however, are difficult to identify visually, and observation conditions often do not permit adequate quantitative sampling of feeding behavior. Moreover, the taxonomically informative morphology of some food species (e.g. swallowed seeds, insect exoskeletons) may be destroyed by the digestive process. Because of these limitations, we used a metagenomic approach to conduct a preliminary, "proof of concept" study of interspecific variation in the insect component of the diets of six sympatric New World monkeys known, based on observational field studies, to differ markedly in their feeding ecology. We used generalized arthropod polymerase chain reaction (PCR) primers and cloning to sequence mitochondrial DNA (mtDNA) sequences of the arthropod cytochrome b (CYT B) gene from fecal samples of wild woolly, titi, saki, capuchin, squirrel, and spider monkeys collected from a single sampling site in western Amazonia where these genera occur sympatrically. We then assigned preliminary taxonomic identifications to the sequences by basic local alignment search tool (BLAST) comparison to arthropod CYT B sequences present in GenBank. This study is the first to use molecular techniques to identify insect prey in primate diets. The results suggest that a metagenomic approach may prove valuable in augmenting and corroborating observational data and increasing the resolution of primate diet studies, although the lack of comparative reference sequences for many South American insects limits the approach at present. As such reference data become available for more animal and plant taxa, this approach also holds promise for studying additional components of primate diets. © 2012 Wiley Periodicals, Inc.

  16. Posterior maxillary (PM) plane and anterior cranial architecture in primates. (United States)

    McCarthy, R C; Lieberman, D E


    This study tests several hypotheses of integration between the cranial base and face in primates. After reviewing the definition and anatomical basis for the posterior maxillary (PM) plane, which demarcates the back of the midface at its junction with the sphenoid, we demonstrate how the PM plane can be identified accurately on radiographs, and confirm that it maintains a 90 degrees angle relative to the Neutral Horizontal Axis of the orbits in all primates. In addition, we use the PM plane to test Dabelow's (1929) hypothesis that the orbits and anterior cranial base are more highly integrated in anthropoids than in strepsirrhines, and we test the hypothesis that the midline anterior cranial base (planum sphenoideum) and anterior cranial floor (planum sphenoideum plus cribriform plate) in primates are highly correlated with each other relative to the PM plane. The mean angle between the anterior cranial base and the PM plane does not differ significantly from 90 degrees in anthropoids, but differs significantly in strepsirrhines. The anterior cranial base and anterior cranial floor, however, correlate well with each other relative to the PM plane in both suborders of primates, independent of orbital orientation and configuration. The PM plane, anterior cranial base, and anterior cranial floor, therefore, form an integrated structural complex, a "facial block," whose orientation relative to the posterior cranial base influences craniofacial shape among anthropoids in which orbital orientation influences the orientation of the anterior cranial base. One such effect is that increases in cranial base flexion shorten the antero-posterior length of the nasopharynx. Copyright 2001 Wiley-Liss, Inc.

  17. A hierarchy of intrinsic timescales across primate cortex. (United States)

    Murray, John D; Bernacchia, Alberto; Freedman, David J; Romo, Ranulfo; Wallis, Jonathan D; Cai, Xinying; Padoa-Schioppa, Camillo; Pasternak, Tatiana; Seo, Hyojung; Lee, Daeyeol; Wang, Xiao-Jing


    Specialization and hierarchy are organizing principles for primate cortex, yet there is little direct evidence for how cortical areas are specialized in the temporal domain. We measured timescales of intrinsic fluctuations in spiking activity across areas and found a hierarchical ordering, with sensory and prefrontal areas exhibiting shorter and longer timescales, respectively. On the basis of our findings, we suggest that intrinsic timescales reflect areal specialization for task-relevant computations over multiple temporal ranges.

  18. Alu repeats: A source for the genesis of primate microsatellites

    Energy Technology Data Exchange (ETDEWEB)

    Arcot, S.S.; Batzer, M.A. [Lawrence Livermore National Lab., CA (United States); Wang, Zhenyuan [Marshfield Medical Research Foundation, WI (United States)] [and others


    As a result of their abundance, relatively uniform distribution, and high degree of polymorphism, microsatellites and minisatellites have become valuable tools in genetic mapping, forensic identity testing, and population studies. In recent years, a number of microsatellite repeats have been found to be associated with Alu interspersed repeated DNA elements. The association of an Alu element with a microsatellite repeat could result from the integration of an Alu element within a preexisting microsatellite repeat. Alternatively, Alu elements could have a direct role in the origin of microsatellite repeats. Errors introduced during reverse transcription of the primary transcript derived from an Alu {open_quotes}master{close_quote} gene or the accumulation of random mutations in the middle A-rich regions and oligo(dA)-rich tails of Alu elements after insertion and subsequent expansion and contraction of these sequences could result in the genesis of a microsatellite repeat. We have tested these hypotheses by a direct evolutionary comparison of the sequences of some recent Alu elements that are found only in humans and are absent from nonhuman primates, as well as some older Alu elements that are present at orthologous positions in a number of nonhuman primates. The origin of {open_quotes}young{close_quotes} Alu insertions, absence of sequences that resemble microsatellite repeats at the orthologous loci in chimpanzees, and the gradual expansion of microsatellite repeats in some old Alu repeats at orthologous positions within the genomes of a number of nonhuman primates suggest that Alu elements are a source for the genesis of primate microsatellite repeats. 48 refs., 5 figs., 3 tabs.

  19. Nonhuman primate positron emission tomography neuroimaging in drug abuse research. (United States)

    Howell, Leonard Lee; Murnane, Kevin Sean


    Positron emission tomography (PET) neuroimaging in nonhuman primates has led to significant advances in our current understanding of the neurobiology and treatment of stimulant addiction in humans. PET neuroimaging has defined the in vivo biodistribution and pharmacokinetics of abused drugs and related these findings to the time course of behavioral effects associated with their addictive properties. With novel radiotracers and enhanced resolution, PET neuroimaging techniques have also characterized in vivo drug interactions with specific protein targets in the brain, including neurotransmitter receptors and transporters. In vivo determinations of cerebral blood flow and metabolism have localized brain circuits implicated in the effects of abused drugs and drug-associated stimuli. Moreover, determinations of the predisposing factors to chronic drug use and long-term neurobiological consequences of chronic drug use, such as potential neurotoxicity, have led to novel insights regarding the pathology and treatment of drug addiction. However, similar approaches clearly need to be extended to drug classes other than stimulants. Although dopaminergic systems have been extensively studied, other neurotransmitter systems known to play a critical role in the pharmacological effects of abused drugs have been largely ignored in nonhuman primate PET neuroimaging. Finally, the study of brain activation with PET neuroimaging has been replaced in humans mostly by functional magnetic resonance imaging (fMRI). There has been some success in implementing pharmacological fMRI in awake nonhuman primates. Nevertheless, the unique versatility of PET imaging will continue to complement the systems-level strengths of fMRI, especially in the context of nonhuman primate drug abuse research.

  20. Spleen necrosis virus, an avian retrovirus, can infect primate cells.


    Koo, H M; Brown, A M; Ron, Y; Dougherty, J P


    Spleen necrosis virus (SNV) is an avian retrovirus that can infect some mammalian cells such as dog cells as well as all avian cells tested to date. We were interested in testing whether SNV could also infect primate cells. For these experiments, we used HeLa and COS-7 cells. Initially, we determined whether the SNV long terminal repeat promoter was functional in HeLa and COS-7 cells. In transient transfection assays, the SNV promoter efficiently directed chloramphenicol acetyltransferase gen...

  1. Primate Auditory Recognition Memory Performance Varies With Sound Type


    Chi-Wing, Ng; Bethany, Plakke; Amy, Poremba


    Neural correlates of auditory processing, including for species-specific vocalizations that convey biological and ethological significance (e.g. social status, kinship, environment),have been identified in a wide variety of areas including the temporal and frontal cortices. However, few studies elucidate how non-human primates interact with these vocalization signals when they are challenged by tasks requiring auditory discrimination, recognition, and/or memory. The present study employs a de...

  2. Influence of personality on primate health, welfare, and happiness


    Robinson, Lauren Marie


    Is personality important for understanding the variation we see in animal welfare? In this thesis, I address that question by studying the association between personality and health, welfare, and happiness in three species of nonhuman primate: rhesus macaques (Macaca mulatta), brown capuchins (Sapajus apella), and chimpanzees (Pan troglodytes). As part of this research I test a newly designed animal welfare questionnaire. In Chapter 1 I review how animal welfare questionnaires can be designed...

  3. Understanding the control of ingestive behavior in primates. (United States)

    Wilson, Mark E; Moore, Carla J; Ethun, Kelly F; Johnson, Zachary P


    This article is part of a Special Issue "Energy Balance". Ingestive behavior in free-ranging populations of nonhuman primates is influenced by resource availability and social group organization and provides valuable insight on the evolution of ecologically adaptive behaviors and physiological systems. As captive populations were established, questions regarding proximate mechanisms that regulate food intake in these animals could be more easily addressed. The availability of these captive populations has led to the use of selected species to understand appetite control or metabolic physiology in humans. Recognizing the difficulty of quantitating food intake in free-ranging groups, the use of captive, singly-housed animals provided a distinct advantage though, at the same time, produced a different social ecology from the animals' natural habitat. However, the recent application of novel technologies to quantitate caloric intake and energy expenditure in free-feeding, socially housed monkeys permits prospective studies that can accurately define how food intake changes in response to any number of interventions in the context of a social environment. This review provides an overview of studies examining food intake using captive nonhuman primates organized into three areas: a) neurochemical regulation of food intake in nonhuman primates; b) whether exposure to specific diets during key developmental periods programs differences in diet preferences or changes the expression of feeding related neuropeptides; and c) how psychosocial factors influence appetite regulation. Because feeding patterns are driven by more than just satiety and orexigenic signals, appreciating how the social context influences pattern of feeding in nonhuman primates may be quite informative for understanding the biological complexity of feeding in humans. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Nannoplankton malformation during the Paleocene-Eocene Thermal Maximum and its paleoecological and paleoceanographic significance (United States)

    Bralower, Timothy J.; Self-Trail, Jean


    The Paleocene-Eocene Thermal Maximum (PETM) is characterized by a transient group of nannoplankton, belonging to the genus Discoaster. Our investigation of expanded shelf sections provides unprecedented detail of the morphology and phylogeny of the transient Discoasterduring the PETM and their relationship with environmental change. We observe a much larger range of morphological variation than previously documented suggesting that the taxa belonged to a plexus of highly gradational morphotypes rather than individual species. We propose that the plexus represents malformed ecophenotypes of a single species that migrated to a deep photic zone refuge during the height of PETM warming and eutrophication. Anomalously, high rates of organic matter remineralization characterized these depths during the event and led to lower saturation levels, which caused malformation. The proposed mechanism explains the co-occurrence of malformed Discoaster with pristine species that grew in the upper photic zone; moreover, it illuminates why malformation is a rare phenomenon in the paleontological record.

  5. Chromium-Isotope and iridium-Abundance Measurements for Late Eocene Impact-Derived Spherule Deposits (United States)

    Kyte, F. T.; Shukolyukov, A.; Hildebrand, A. R.; Lugmair, G. W.; Hanova, J.


    The late Eocene (approx. 35 Ma) was a time of multiple large body impacts superimposed within an interval of dust accretion. At least two spherule layers are preserved in deep sea sediments: North American microtektites and the slightly older cpx spherules. The two largest impact structures in the Cenozoic, the 45 km Chesapeake Bay structure and the 100 km Popigai structure, are indicated as the respective spherule sources. Enhanced 3He concentrations extending across a 3 m.y. duration in upper Eocene sediments from the Massignano quarry in Italy indicate accretion of dust over this time interval. To characterize one of the impactors we have analyzed splits from the 125-250 micron cpx spherules from ODP 709C, and two fractions from the Massignano layer. Splits of each sample were analyzed for minor and trace elements by instrumental activation analysis (INAA) including Ir, Cr, Fe, Ni, and Co. Additional splits were analyzed for their Cr-isotopic composition, using thermal ionization mass spectrometry. Significant concentrations of Ir were found in all samples, with the highest levels in the Massignano coarse sample and the lowest in the 709C sample. In all cases, element/Ir ratios are much higher than in chondritic meteorites; this may reflect elemental fractionation due to preferential concentration of Cr in spinel growing in the impact fireball. The Cr-isotopic compositions of the 709C and Massignano coarse samples are both non-terrestrial with a positive epsilon 53, indicating a 53Cr/52Cr ratio higher than in terrestrial materials. Microprobe surveys showed that the Massignano samples had significant fine grained oxide grains (mixed with the spherules in the coarse sample) that were not Ni- or Cr-rich, including Ti-rich spinels (likely terrestrial contaminants). In contrast, the ODP 709C sample is a pure extract of generally well-preserved cpx spherules composed of clinopyroxene in a glass matrix. Both the Massignano coarse and the 709C cpx samples have

  6. Early-middle Eocene birds from the Lillebaelt Clay Formation of Denmark

    DEFF Research Database (Denmark)

    Lindow, Bent Erik Kramer


    The marine Lillebaelt Clay Formation of central Denmark is of early-middle Eocene age (late Ypresian - middle Lutetian; microfossil zones NP 13-NP 15). Over 20 bird fossils collected by amateur palaeontologists have been acquired through the Danish national ‘Danekrae' fossil treasure trove...... legislation. The fossils are preserved in clay ironstone concretions and almost two-thirds are isolated skulls preserved three-dimensionally. Bird fossils of this age and degree of preservation are rare in an international context. The fossils indicate a very diverse assemblage consisting of both marine...... and terrestrial forms. These include at least one pelagornithid or 'pseudo-toothed bird'; two or three taxa with charadriiform affinities (shorebirds and allies); a massive, narrow-beaked psittaciform (parrots and allies); a large rallid (rail) and one lithornithid (extinct, volant palaeognaths). The Lillebaelt...

  7. Taphonomy and abundance of birds from the Lower Eocene Fur Formation of Denmark

    DEFF Research Database (Denmark)

    Dyke, Gareth; Lindow, Bent Erik Kramer


    The pattern, pace and extent of the evolutionary radiation of modern birds (Neornithes) by the end-Cretaceous (65 Ma) has long been debated. Well-dated, taphonomically understood and phylogenetically constrained fossil birds from both sides of the Cretaceous-Paleogene (K-Pg) boundary are required...... to quantify the shape of this radiation, but have largely been lacking. Here we report on a large collection of fossil birds from the Lower Eocene of Denmark (ca. 54 Ma) that includes three-dimensionally preserved, articulated specimens from carbonate concretions as well as skeletal imprints and feathers....... These birds are from a marine diatomite sequence (the Fur Formation), a low-energy deep-water preservational environment unique to the Cretaceous and Paleogene avian fossil record. We present taphonomic and palaeoecological information gleaned from these birds that in combination with phylogenetic data have...

  8. Earth Pressure at rest of Søvind Marl – a highly overconsolidated Eocene clay

    DEFF Research Database (Denmark)

    Grønbech, Gitte Lyng; Ibsen, Lars Bo; Nielsen, Benjaminn Nordahl


    with a constant rate of strain were conducted on Søvind Marl in the Danish Continuous Loading Oedometer Apparatus, which enables test water to be applied at 200 kPa, and measures the horizontal stresses via pressure gauges placed in a stiff oedometer ring. The horizontal and vertical stresses were measured from......The present study evaluated earth pressure at rest, K0, in highly overconsolidated Eocene clay called Søvind Marl, which exhibits extremely high plasticity indices of up to 300%, a highly fissured structure, and preconsolidation stresses up to 6,800 kPa. Continuous Loading Oedometer (CLO) tests...... in situ stresses to various stress levels to estimate continuous K0 development in this highly overconsolidated clay. The normally consolidated earth pressure at rest was found for two different sample ages of Søvind Marl to be between 0.42 and 0.68. Results indicated the overconsolidated K0 reached...

  9. Early Eocene fossils suggest that the mammalian order Perissodactyla originated in India. (United States)

    Rose, Kenneth D; Holbrook, Luke T; Rana, Rajendra S; Kumar, Kishor; Jones, Katrina E; Ahrens, Heather E; Missiaen, Pieter; Sahni, Ashok; Smith, Thierry


    Cambaytheres (Cambaytherium, Nakusia and Kalitherium) are recently discovered early Eocene placental mammals from the Indo-Pakistan region. They have been assigned to either Perissodactyla (the clade including horses, tapirs and rhinos, which is a member of the superorder Laurasiatheria) or Anthracobunidae, an obscure family that has been variously considered artiodactyls or perissodactyls, but most recently placed at the base of Proboscidea or of Tethytheria (Proboscidea+Sirenia, superorder Afrotheria). Here we report new dental, cranial and postcranial fossils of Cambaytherium, from the Cambay Shale Formation, Gujarat, India (~54.5 Myr). These fossils demonstrate that cambaytheres occupy a pivotal position as the sister taxon of Perissodactyla, thereby providing insight on the phylogenetic and biogeographic origin of Perissodactyla. The presence of the sister group of perissodactyls in western India near or before the time of collision suggests that Perissodactyla may have originated on the Indian Plate during its final drift toward Asia.

  10. Dinocyst taphonomy, impact craters, cyst ghosts, and the Paleocene-Eocene thermal maximum (PETM) (United States)

    Edwards, Lucy E.


    Dinocysts recovered from sediments related to the Chesapeake Bay impact structure in Virginia and the earliest Eocene suboxic environment in Maryland show strange and intriguing details of preservation. Features such as curled processes, opaque debris, breakage, microborings and cyst ghosts, among others, invite speculation about catastrophic depositional processes, rapid burial and biological and chemical decay. Selected specimens from seven cores taken in the coastal plain of Virginia and Maryland show abnormal preservation features in various combinations that merit illustration, description, discussion and further study. Although the depositional environments described are extreme, many of the features discussed are known from, or could be found in, other environments. These environments will show both similarities to and differences from the extreme environments here.

  11. Eocene lantern fruits from Gondwanan Patagonia and the early origins of Solanaceae. (United States)

    Wilf, Peter; Carvalho, Mónica R; Gandolfo, María A; Cúneo, N Rubén


    The nightshade family Solanaceae holds exceptional economic and cultural importance. The early diversification of Solanaceae is thought to have occurred in South America during its separation from Gondwana, but the family's sparse fossil record provides few insights. We report 52.2-million-year-old lantern fruits from terminal-Gondwanan Patagonia, featuring highly inflated, five-lobed calyces, as a newly identified species of the derived, diverse New World genus Physalis (e.g., groundcherries and tomatillos). The fossils are considerably older than corresponding molecular divergence dates and demonstrate an ancient history for the inflated calyx syndrome. The derived position of these early Eocene fossils shows that Solanaceae were well diversified long before final Gondwanan breakup. Copyright © 2017, American Association for the Advancement of Science.

  12. Preconsolidation of Søvind Marl - a highly fissured Eocene clay

    DEFF Research Database (Denmark)

    Grønbech, Gitte Lyng; Ibsen, Lars Bo; Nielsen, Benjaminn Nordahl


    Determination of the preconsolidation stresses is a key tool in geotechnical engineering used to evaluate and estimate the behavior of soils. However, it has been proven difficult to accurately estimate the preconsolidation in highly fissured overconsolidated clays, due to the effect of the fissu......Determination of the preconsolidation stresses is a key tool in geotechnical engineering used to evaluate and estimate the behavior of soils. However, it has been proven difficult to accurately estimate the preconsolidation in highly fissured overconsolidated clays, due to the effect...... of the fissured structure of the clay. This article presents oedometer tests performed on Søvind Marl, a plastic Eocene clay, with a high presence of fissures and slickensides. Four incremental loading oedometer tests and four continuous loading oedometer tests were performed in order to determine...

  13. Pristine Early Eocene wood buried deeply in kimberlite from northern Canada. (United States)

    Wolfe, Alexander P; Csank, Adam Z; Reyes, Alberto V; McKellar, Ryan C; Tappert, Ralf; Muehlenbachs, Karlis


    We report exceptional preservation of fossil wood buried deeply in a kimberlite pipe that intruded northwestern Canada's Slave Province 53.3±0.6 million years ago (Ma), revealed during excavation of diamond source rock. The wood originated from forest surrounding the eruption zone and collapsed into the diatreme before resettling in volcaniclastic kimberlite to depths >300 m, where it was mummified in a sterile environment. Anatomy of the unpermineralized wood permits conclusive identification to the genus Metasequoia (Cupressaceae). The wood yields genuine cellulose and occluded amber, both of which have been characterized spectroscopically and isotopically. From cellulose δ(18)O and δ(2)H measurements, we infer that Early Eocene paleoclimates in the western Canadian subarctic were 12-17°C warmer and four times wetter than present. Canadian kimberlites offer Lagerstätte-quality preservation of wood from a region with limited alternate sources of paleobotanical information.

  14. Xenoliths in Eocene lavas from Central Tibet record carbonated metasomatism of the lithosphere (United States)

    Goussin, Fanny; Cordier, Carole; Boulvais, Philippe; Guillot, Stéphane; Roperch, Pierrick; Replumaz, Anne


    Cenozoic post-collisional volcanism of the Tibetan Plateau, emplaced on an accreted continental margin under compression, could bring important information regarding the edification of the Plateau. In this study, we combined petrography, whole rock geochemistry, stable isotopes and in situ mineral analysis to decipher the genesis of Eocene-Oligocene magmatic rocks from the Nangqian basin (35-38 Ma, [Spurlin et al., 2005; Xu et al., 2016]), located at the hinge between Central Tibet and the Eastern Indo-Asia Collision Zone. Our dataset includes potassic trachyandesites; amphibole-bearing potassic trachytes; and rare ultrapotassic (K2O/Na2O ≥ 4) mafic syenites. All samples have high REE abundances (La = 100 - 500 x primitive mantle). Fractionation of heavy REE (Gd/YbN > 3) indicates melting in the garnet stability field, and relative depletion in high-field strength elements (Nb, Ta) indicates a selective enrichment of the source by metasomatic fluids. This metasomatism event is also evidenced by the occurrence of re-equilibrated mantle xenocrysts of phlogopite (Mg# = 88 - 90 and Cr2O3 content = 0.9 - 1.82 wt%) in mafic syenites. Potassic trachyandesites have specific composition, with negative Zr-Hf anomaly and low Hf/Sm (0.2 - 0.4). Indeed, they include xenocrystic aggregates, composed of magmatic clinopyroxene, apatite and subordinate biotite and feldspar, with interstitial calcite and dolomite. δ18OV -SMOW (9.2 - 11.0 ) and δ13CV -PDB (-6.1 - -4.0 ) of these rocks indicate the presence of primary, mantle-derived carbonates. In situ analysis of the major and trace element compositions of the carbonates, clinopyroxenes and apatites further suggest that these aggregates represent cumulates of a carbonate-bearing magma. These xenoliths thus show that the lithospheric mantle was also metasomatized by CO2-rich fluids. Cenozoic carbonatites in China have been identified in Maoniuping in Western Sichuan (31.7 Ma), Lixian in the Western Qinlin (22-23 Ma), and

  15. Gigantism in unique biogenic magnetite at the Paleocene–Eocene Thermal Maximum (United States)

    Schumann, Dirk; Raub, Timothy D.; Kopp, Robert E.; Guerquin-Kern, Jean-Luc; Wu, Ting-Di; Rouiller, Isabelle; Smirnov, Aleksey V.; Sears, S. Kelly; Lücken, Uwe; Tikoo, Sonia M.; Hesse, Reinhard; Kirschvink, Joseph L.; Vali, Hojatollah


    We report the discovery of exceptionally large biogenic magnetite crystals in clay-rich sediments spanning the Paleocene–Eocene Thermal Maximum (PETM) in a borehole at Ancora, NJ. Aside from previously described abundant bacterial magnetofossils, electron microscopy reveals novel spearhead-like and spindle-like magnetite up to 4 μm long and hexaoctahedral prisms up to 1.4 μm long. Similar to magnetite produced by magnetotactic bacteria, these single-crystal particles exhibit chemical composition, lattice perfection, and oxygen isotopes consistent with an aquatic origin. Electron holography indicates single-domain magnetization despite their large crystal size. We suggest that the development of a thick suboxic zone with high iron bioavailability—a product of dramatic changes in weathering and sedimentation patterns driven by severe global warming—drove diversification of magnetite-forming organisms, likely including eukaryotes. PMID:18936486

  16. A Transient Rise in Tropical Sea Surface Temperature During the Paleocene-Eocene Thermal Maximum (United States)

    Zachos, James C.; Wara, Michael W.; Bohaty, Steven; Delaney, Margaret L.; Petrizzo, Maria Rose; Brill, Amanda; Bralower, Timothy J.; Premoli-Silva, Isabella


    The Paleocene-Eocene Thermal Maximum (PETM) has been attributed to a rapid rise in greenhouse gas levels. If so, warming should have occurred at all latitudes, although amplified toward the poles. Existing records reveal an increase in high-latitude sea surface temperatures (SSTs) (8° to 10°C) and in bottom water temperatures (4° to 5°C). To date, however, the character of the tropical SST response during this event remains unconstrained. Here we address this deficiency by using paired oxygen isotope and minor element (magnesium/calcium) ratios of planktonic foraminifera from a tropical Pacific core to estimate changes in SST. Using mixed-layer foraminifera, we found that the combined proxies imply a 4° to 5°C rise in Pacific SST during the PETM. These results would necessitate a rise in atmospheric pCO2 to levels three to four times as high as those estimated for the late Paleocene.

  17. Palaeoenvironment of Eocene prodelta in Spitsbergen recorded by the trace fossil Phycosiphon incertum

    Directory of Open Access Journals (Sweden)

    Francisco Javier Rodríguez-Tovar


    Full Text Available Ichnological, sedimentological and geochemical analyses were conducted on the Eocene Frysjaodden Formation in order to interpret palaeoenvironment prodelta sediments in the Central Basin of Spitsbergen. Phycosiphon incertum is the exclusive ichnotaxon showing differences in size, distribution, abundance and density, and relation to laminated/bioturbated intervals. Large P. incertum mainly occur dispersed, isolated and randomly distributed throughout the weakly laminated/non-laminated intervals. Small P. incertum occur occasionally in patches of several burrows within laminated intervals or as densely packed burrows in thin horizons in laminated intervals or constituting fully bioturbated intervals that are several centimetres thick. Ichnological changes are mainly controlled by oxygenation, although the availability of benthic food cannot be discarded. Changes in oxygenation and rate of sedimentation can be correlated with the registered variations in the Bouma sequence of the distal turbiditic beds within prodeltal shelf sediments.

  18. Late Cretaceous to mid Eocene plate boundaries in the southwest Pacific (United States)

    Matthews, Kara J.; Dietmar Müller, R.; Whittaker, Joanne; Flament, Nicolas; Seton, Maria


    The late Cretaceous to mid Eocene history of the southwest and southernmost Pacific has been subject to starkly contrasting interpretations, ranging from relative tectonic quiescence with the Lord Howe Rise (LHR) being part of the Pacific plate to a dynamic subduction setting. In the first scenario the Tasman Sea would have formed as a consequence of divergence between the Pacific and Australian plates, whereas in the second scenario it would have formed as a marginal basin associated with subduction. The first scenario is supported by a number of arguments, including a lack of evidence for deformation and tectonic activity in New Zealand during this period and a geodynamic modelling inference, namely that the bend in the Hawaiian-Emperor chain can be better reproduced if the LHR is part of the Pacific plate. The second scenario is supported by regional plate kinematic models reconciling a variety of observations including back-arc basin formation and destruction through time and the history of arc-continent collisions. The primary problem with the first scenario is the use of a plate circuit that leaves relative motion between East and West Antarctica unconstrained, leading to an improbable history of periodic compression and extension. The main problem with the alternative scenario is a lack of sampled late Cretaceous volcanic arc rocks east of the LHR. We analysed available geological and geophysical data to constrain the locations of and movements along the plate boundaries in the southwest and southern Pacific from the late Cretaceous to mid Eocene, and assessed how Pacific plate motion is best quantified during this period. Geological and geophysical evidence suggests that a plate boundary separated the Pacific plate from the LHR. The distribution of lower mantle slab material that is imaged by seismic tomography beneath New Zealand is best explained if subduction occurred to the east of the LHR during the entire late Cretaceous to mid Eocene period. Rocks

  19. Groundwater pollution risk mapping for the Eocene aquifer of the Oum Er-Rabia basin, Morocco (United States)

    Ettazarini, Said


    Sustainable development requires the management and preservation of water resources indispensable for all human activities. When groundwater constitutes the main water resource, vulnerability maps therefore are an important tool for identifying zones of high pollution risk and taking preventive measures in potential pollution sites. The vulnerability assessment for the Eocene aquifer in the Moroccan basin of Oum Er-Rabia is based on the DRASTIC method that uses seven parameters summarizing climatic, geological, and hydrogeological conditions controlling the seepage of pollutant substances to groundwater. Vulnerability maps were produced by using GIS techniques and applying the “generic” and “agricultural” models according to the DRASTIC charter. Resulting maps revealed that the aquifer is highly vulnerable in the western part of the basin and areas being under high contamination risk are more extensive when the “agricultural” model was applied.

  20. New Carcharhiniform Sharks (Chondrichthyes, Elasmobranchii) from the Early to Middle Eocene of Seymour Island, Antarctic Peninsula (United States)

    Engelbrecht, Andrea; Mörs, Thomas; Reguero, Marcelo A.; Kriwet, Jürgen


    Seymour Island, Antarctic Peninsula, is known for its wealth of fossil remains. This island provides one of the richest fossiliferous Paleogene sequences in the world. Chondrichthyans seemingly dominate this Eocene marine fauna and offer a rare insight into high-latitude faunas during the Palaeogene. So far, only a few isolated teeth of carcharhinid sharks have been reported from Seymour Island. Bulk sampling in the well-exposed La Meseta and Submeseta formations yielded new and abundant chondrichthyan material, including numerous teeth of carcharhinid and triakid sharks. Here, we present a reevaluation of the previously described carcharhinid remains and a description of new taxa: Meridiogaleus cristatus, gen. et sp. nov., Kallodentis rythistemma, gen. et sp. nov., Abdounia richteri, sp. nov., and Abdounia mesetae, sp. nov. The carcharhiniforms Mustelus sp. and Galeorhinus sp. are reported based on rare material, whereas teeth previously assigned to Scoliodon represent a nomen dubium. PMID:29551850

  1. Characterization of interleukin-8 receptors in non-human primates

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez, V.; Coto, E.; Gonzalez-Roces, S.; Lopez-Larrea, C. [Hospital Central de Asturias, Oviedo (Spain)] [and others


    Interleukin-8 is a chemokine with a potent neutrophil chemoatractant activity. In humans, two different cDNAs encoding human IL8 receptors designated IL8RA and IL8RB have been cloned. IL8RA binds IL8, while IL8RB binds IL8 as well as other {alpha}-chemokines. Both human IL8Rs are encoded by two genes physically linked on chromosome 2. The IL8RA and IL8RB genes have open reading frames (ORF) lacking introns. By direct sequencing of the polymerase chain reaction products, we sequenced the IL8R genes of cell lines from four non-human primates: chimpanzee, gorilla, orangutan, and macaca. The IL8RB encodes an ORF in the four non-human primates, showing 95%-99% similarity to the human IL8RB sequence. The IL8RA homologue in gorilla and chimpanzee consisted of two ORF 98%-99% identical to the human sequence. The macaca and orangutan IL8RA homologues are pseudogenes: a 2 base pair insertion generated a sequence with several stop codons. In addition, we describe the physical linkage of these genes in the four non-human primates and discuss the evolutionary implications of these findings. 25 refs., 5 figs., 3 tabs.

  2. Adaptive cultural transmission biases in children and nonhuman primates. (United States)

    Price, Elizabeth E; Wood, Lara A; Whiten, Andrew


    Comparative and evolutionary developmental analyses seek to discover the similarities and differences between humans and non-human species that might illuminate both the evolutionary foundations of our nature that we share with other animals, and the distinctive characteristics that make human development unique. As our closest animal relatives, with whom we last shared common ancestry, non-human primates have been particularly important in this endeavour. Such studies have focused on social learning, traditions, and culture, and have discovered much about the 'how' of social learning, concerned with key underlying processes such as imitation and emulation. One of the core discoveries is that the adaptive adjustment of social learning options to different contexts is not unique to human, therefore multiple new strands of research have begun to focus on more subtle questions about when, from whom, and why such learning occurs. Here we review illustrative studies on both human infants and young children and on non-human primates to identify the similarities shared more broadly across the primate order, and the apparent specialisms that distinguish human development. Adaptive biases in social learning discussed include those modulated by task comprehension, experience, conformity to majorities, and the age, skill, proficiency and familiarity of potential alternative cultural models. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.

  3. Facies analysis and sequence stratigraphy of the Eocene successions, east Beni Suef area, eastern Desert, Egypt (United States)

    Saber, Shaban G.; Salama, Yasser F.


    Three Eocene stratigraphic successions east of the Beni Suef area are described and measured. These successions are made up of four rock units that are from base to top: Qarara (upper Lutetian), El Fashn (Bartonian), Beni Suef, and Maadi (Priabonian) formations. A detailed facies and sequence analysis unravels the stratigraphic framework and constructs a depositional model for the Middle-Upper Eocene succession. Ten microfacies types were grouped into four facies associations on a homoclinal ramp that compose the Upper Lutetian-Priabonian succession exposed in the east Beni Suef area. The depositional environment varied from a shallow to deep ramp setting. Four third-order depositional sequences were identified in the studied sections. The sequence boundaries are paleosoil horizons that can be traced throughout the entire outcrop area. Missing biozones are also evidence of the sequence boundaries. The history of these sequences mirrors the eustatic sea-level changes and the local tectonics in the region. Each sequence comprises facies associations that make up lowstand and/or transgressive and highstand systems tracts. The lowstand systems tract (LST) deposits are mainly sandstone facies and in Sequences 3 and 4 at Gabal Abyiad and Gabal Homret Shaibun respectively. The transgressive systems tract (TST) of Sequence 1 is dominated by nummulitic facies at Gabal Diya. The shale, mudstone and wackestone facies with planktic foraminifera and echinoids dominate the TST of Sequences 2 and 3 at Gabal Abyiad and Gabal Homret Shaibun respectively. The highstand systems tract (HST) of the studied sections is characterized by benthic foraminifera and bryozoan wackestone and packstone facies.

  4. Eocene age of the Baranowski Glacier Group at Red Hill, King George Island, West Antarctica

    Directory of Open Access Journals (Sweden)

    Mozer Anna


    Full Text Available Radiometric and geochemical studies were carried out at Red Hill in the southern part of King George Island (South Shetland Islands, northern Antarctic Peninsula on the Bransfield Strait coast. The rock succession at Red Hill has been determined to represent the Baranowski Glacier Group that was previously assigned a Late Cretaceous age. Two formations were distinguished within this succession: the lower Llano Point Formation and the upper Zamek Formation. These formations have stratotypes defined further to the north on the western coast of Admiralty Bay. On Red Hill the Llano Point Formation consists of terrestrial lavas and pyroclastic breccia; the Zamek Formation consist predominantly of fine to coarse tuff, pyroclastic breccia, lavas, tuffaceous mud-, silt-, and sandstone, locally conglomeratic. The lower part of the Zamek Formation contains plant detritus (Nothofagus, dicotyledonous, thermophilous ferns and numerous coal seams (vitrinitic composition that confirm the abundance of vegetation on stratovolcanic slopes and surrounding lowlands at that time. Selected basic to intermediate igneous rocks from the succession have been analysed for the whole-rock K-Ar age determination. The obtained results indicate that the Red Hill succession was formed in two stages: (1 from about 51–50 Ma; and (2 46–42 Ma, i.e. during the Early to Middle Eocene. This, in combination with other data obtained from other Baranowski Glacier Group exposures on western coast of Admiralty Bay, confirms the recently defined position of the volcano-clastic succession in the stratigraphic scheme of King George Island. The new stratigraphic position and lithofacies development of the Red Hill succession strongly suggest its correlation with other Eocene formations containing fossil plants and coal seams that commonly occur on King George Island.

  5. Estimates of Cenozoic Forearc Subduction off Southwestern Mexico: Constraints on Eocene- Miocene Reconstructions (United States)

    Keppie, J. D.; Moran-Zenteno, D. J.; Martiny, B. M.; Gonzalez-Torres, E.


    Traditional Cenozoic reconstructions of southern Mexico that place the Chortis block (Honduras and northern Nicaragua) adjacent southwestern Mexico using the Motagua Fault Zone violate plate tectonic principles, and are inconsistent with the presence of undeformed upper Cretaceous - Recent sediments in the Gulf of Tehuantepec that straddle the westward projection of the Motagua Fault Zone, the inferred northern boundary of the Chortis block. Rotating the Chortis block about a rotation pole near Santiago (Chile) places it to the southwest of its present position at 45 Ma with the Farallon Plate lying off southwestern Mexico. Examination of the geological record of southwestern Mexico (102-96°W) records several synchronous events in the upper Oligocene- lower Miocene (29-19 Ma): (1) an hiatus in arc magmatism; (2) removal of a wide (~210 km) upper Eocene-lower Oligocene forearc; (3) exhumation of 13-20 km of upper Eocene-lower Oligocene arc along the present day coast; and (4) breakup of the Farallon Plate. We suggest that the magmatic hiatus was caused by subduction of the forearc, which replaced the mantle wedge by relatively cool crust and has since been deeply subducted. Potential causes for subduction of the forearc include collision of an oceanic plateau with the trench, and a change in plate kinematics synchronous with breakup of the Farallon Plate and initiation of the Guadalupe-Nazca spreading ridge. Following removal of the forearc, arc magmatism resumed in two segments offset by the Veracruz-Oaxaca Line: (i) the 19 Ma to Present E-W Trans-Mexican Volcanic Belt; and (ii) the 22-10 Ma WNW part of the Central American Volcanic Arc. Estimates of the dip of the Benioff zone based on Miocene arc/forearc widths indicate that it changed from 11 to 39 degrees (west to east) across the Veracruz-Oaxaca Line, which is interpreted as a transform fault with a ~100 km dextral offset.

  6. Arctic hydrology during global warming at the Palaeocene/Eocene thermal maximum. (United States)

    Pagani, Mark; Pedentchouk, Nikolai; Huber, Matthew; Sluijs, Appy; Schouten, Stefan; Brinkhuis, Henk; Damsté, Jaap S Sinninghe; Dickens, Gerald R


    The Palaeocene/Eocene thermal maximum represents a period of rapid, extreme global warming 55 million years ago, superimposed on an already warm world. This warming is associated with a severe shoaling of the ocean calcite compensation depth and a >2.5 per mil negative carbon isotope excursion in marine and soil carbonates. Together these observations indicate a massive release of 13C-depleted carbon and greenhouse-gas-induced warming. Recently, sediments were recovered from the central Arctic Ocean, providing the first opportunity to evaluate the environmental response at the North Pole at this time. Here we present stable hydrogen and carbon isotope measurements of terrestrial-plant- and aquatic-derived n-alkanes that record changes in hydrology, including surface water salinity and precipitation, and the global carbon cycle. Hydrogen isotope records are interpreted as documenting decreased rainout during moisture transport from lower latitudes and increased moisture delivery to the Arctic at the onset of the Palaeocene/Eocene thermal maximum, consistent with predictions of poleward storm track migrations during global warming. The terrestrial-plant carbon isotope excursion (about -4.5 to -6 per mil) is substantially larger than those of marine carbonates. Previously, this offset was explained by the physiological response of plants to increases in surface humidity. But this mechanism is not an effective explanation in this wet Arctic setting, leading us to hypothesize that the true magnitude of the excursion--and associated carbon input--was greater than originally surmised. Greater carbon release and strong hydrological cycle feedbacks may help explain the maintenance of this unprecedented warmth.

  7. Southern ocean warming, sea level and hydrological change during the Paleocene-Eocene thermal maximum

    Directory of Open Access Journals (Sweden)

    A. Sluijs


    Full Text Available A brief (~150 kyr period of widespread global average surface warming marks the transition between the Paleocene and Eocene epochs, ~56 million years ago. This so-called "Paleocene-Eocene thermal maximum" (PETM is associated with the massive injection of 13C-depleted carbon, reflected in a negative carbon isotope excursion (CIE. Biotic responses include a global abundance peak (acme of the subtropical dinoflagellate Apectodinium. Here we identify the PETM in a marine sedimentary sequence deposited on the East Tasman Plateau at Ocean Drilling Program (ODP Site 1172 and show, based on the organic paleothermometer TEX86, that southwest Pacific sea surface temperatures increased from ~26 °C to ~33°C during the PETM. Such temperatures before, during and after the PETM are >10 °C warmer than predicted by paleoclimate model simulations for this latitude. In part, this discrepancy may be explained by potential seasonal biases in the TEX86 proxy in polar oceans. Additionally, the data suggest that not only Arctic, but also Antarctic temperatures may be underestimated in simulations of ancient greenhouse climates by current generation fully coupled climate models. An early influx of abundant Apectodinium confirms that environmental change preceded the CIE on a global scale. Organic dinoflagellate cyst assemblages suggest a local decrease in the amount of river run off reaching the core site during the PETM, possibly in concert with eustatic rise. Moreover, the assemblages suggest changes in seasonality of the regional hydrological system and storm activity. Finally, significant variation in dinoflagellate cyst assemblages during the PETM indicates that southwest Pacific climates varied significantly over time scales of 103 – 104 years during this event, a finding comparable to similar studies of PETM successions from the New Jersey Shelf.

  8. Geochemistry of East Antarctic Margin Sediments Spanning the Eocene Oligocene Transition. (United States)

    Light, J. J.; Passchier, S.


    The Eocene Oligocene Transition (EOT) 34 million years ago (Ma), marked the global climate change from greenhouse to icehouse, and the full establishment of the East Antarctic Ice Sheet (EAIS). The initiation of the EAIS during the EOT is believed to have been a step-wise transition; however, data resolution is low and merits the need for further study. The purpose of this study is to expand upon existing knowledge of EAIS dynamics spanning the EOT by creating a higher resolution geochemical record of cores taken from continental shelf sites 1166 in Prydz Bay and U1360 from the Wilkes Land margin. We used Inductively Coupled Plasma Optical Emission Spectrometry and Mass Spectrometry (ICP-OES/ ICP-MS) to determine the bulk chemical composition of samples. Results were used to calculate the Chemical Index of Alteration (CIA), Al2O3/TiO2 ratios, and trace elemental variation down core. CIA values for the early Oligocene in Site U1360 indicate an arid colder environment less likely to be chemically weathered. In contrast, Hole 1166A shows values similar to average shales that increase up core and abruptly decrease at the overlying Neogene diamict, suggesting a warmer more humid environment at Prydz Bay during the late Eocene. Al2O3/TiO2 ratios were used to evaluate mud provenance changes at each site. At site 1166 redox sensitive elements (Cr, Ni, and V) show similar down core distributions to one another. The changes in elemental intensities are likely being controlled by factors such as sediment provenance, changes in redox conditions and surficial weathering. We expect the outcomes of this study to allow us to interpret regional depositional environments at a higher resolution, as well as to shed light on the EAIS's step-wise initiation.

  9. Taxonomic description of in situ bee pollen from the middle Eocene of Germany (United States)

    Grímsson, FriĐgeir; Zetter, Reinhard; Labandeira, Conrad C.; Engel, Michael S.; Wappler, Torsten


    Abstract The middle Eocene Messel and Eckfeld localities are renowned for their excellently preserved faunas and diverse floras. Here we describe for the first time pollen from insect-pollinated plants found in situ on well-preserved ancient bees using light and scanning electron microscopy. There have been 140 pollen types reported from Messel and 162 pollen types from Eckfeld. Here we document 23 pollen types, six from Messel and 18 from Eckfeld (one is shared). The taxa reported here are all pollinated by insects and mostly not recovered in the previously studied dispersed fossil pollen records. Typically, a single or two pollen types are found on each fossil bee specimen, the maximum number of distinct pollen types on a single individual is five. Only five of the 23 pollen types obtained are angiosperms of unknown affinity, the remainder cover a broad taxonomic range of angiosperm trees and include members of several major clades: monocots (1 pollen type), fabids (7), malvids (4), asterids (5) and other core eudicots (1). Seven types each can be assigned to individual genera or infrafamilial clades. Since bees visit only flowers in the relative vicinity of their habitat, the recovered pollen provides a unique insight into the autochthonous palaeo-flora. The coexistence of taxa such as Decodon, Elaeocarpus, Mortoniodendron and other Tilioideae, Mastixoideae, Olax, Pouteria and Nyssa confirms current views that diverse, thermophilic forests thrived at the Messel and Eckfeld localities, probably under a warm subtropical, fully humid climate. Our study calls for increased attention to pollen found in situ on pollen-harvesting insects such as bees, which can provide new insights on insect-pollinated plants and complement even detailed palaeo-palynological knowledge obtained mostly from pollen of wind-pollinated plants in the dispersed pollen record of sediments. In the case of Elaeocarpus, Mortoniodendron, Olax and Pouteria the pollen collected by the middle Eocene

  10. Occurrence of gigantic biogenic magnetite during the Paleocene-Eocene Thermal Maximum (United States)

    Schumann, D.; Raub, T. D.; Kopp, R. E.; Guerquin-Kern, J. L.; Wu, T. D.; Rouiller, I.; Smirnov, A. V.; Sears, S. K.; Lücken, U.; Tikoo, S. M.; Hesse, R.; Kirschvink, J. L.; Vali, H.


    The Paleocene-Eocene Thermal Maximum (PETM) is one of the most severe climatic events of the Cenozoic Era. A massive injection of light carbon into the oceans and atmosphere over a few thousand of years triggered drastic perturbation of Earth's climate resulting in abrupt global warming of ~5-9oC [Sluijs et al., 2007] that persisted for ~180,000 years. This episode is marked by the diversification and radiation of terrestrial plants and mammals while in the marine realm numerous deep-sea benthic foraminifera species disappeared and new forms evolved. Sediments deposited during the PETM are clay-rich and contain distinct evidence of these climatic changes. Kopp et al., (2007) and Lippert & Zachos (2007) report an extraordinary magnetofossil ‘Lagerstätte' in lowermost Eocene kaolinite-rich clay sediments deposited at subtropical paleolatitude in the Atlantic Coastal Plain of New Jersey, USA. Magnetofossils are magnetic particles produced most abundantly by magnetotactic bacteria. Kopp et al. (2007) and Lippert & Zachos (2007) used ferromagnetic resonance (FMR) spectroscopy, other rock magnetic methods, and transmission electron microscopy (TEM) of magnetic separates to characterize sediments from boreholes at Ancora (ODP Leg 174AX) and Wilson Lake, NJ, respectively. These sediments contain abundant ~40- to 300-nm cuboidal, elongate-prismatic and bullet-shaped magnetofossils, sometimes arranged in short chains, resembling crystals in living magnetotactic bacteria. Despite the scarcity of intact magnetofossil chains, the asymmetry ratios of the FMR spectra reflects a profusion of elongate single domain (SD) crystals and/or chains. Here we address both conundrums by reporting the discovery from these same sediments of exceptionally large and novel biogenic magnetite crystals unlike any previously reported from living organisms or from sediments. Aside from abundant bacterial magnetofossils, electron microscopy reveals novel spearhead-like and spindle-like magnetite

  11. Characterization of the fecal microbiome from non-human wild primates reveals species specific microbial communities.

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    Suleyman Yildirim

    Full Text Available BACKGROUND: Host-associated microbes comprise an integral part of animal digestive systems and these interactions have a long evolutionary history. It has been hypothesized that the gastrointestinal microbiome of humans and other non-human primates may have played significant roles in host evolution by facilitating a range of dietary adaptations. We have undertaken a comparative sequencing survey of the gastrointestinal microbiomes of several non-human primate species, with the goal of better understanding how these microbiomes relate to the evolution of non-human primate diversity. Here we present a comparative analysis of gastrointestinal microbial communities from three different species of Old World wild monkeys. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed fecal samples from three different wild non-human primate species (black-and-white colobus [Colubus guereza], red colobus [Piliocolobus tephrosceles], and red-tailed guenon [Cercopithecus ascanius]. Three samples from each species were subjected to small subunit rRNA tag pyrosequencing. Firmicutes comprised the vast majority of the phyla in each sample. Other phyla represented were Bacterioidetes, Proteobacteria, Spirochaetes, Actinobacteria, Verrucomicrobia, Lentisphaerae, Tenericutes, Planctomycetes, Fibrobacateres, and TM7. Bray-Curtis similarity analysis of these microbiomes indicated that microbial community composition within the same primate species are more similar to each other than to those of different primate species. Comparison of fecal microbiota from non-human primates with microbiota of human stool samples obtained in previous studies revealed that the gut microbiota of these primates are distinct and reflect host phylogeny. CONCLUSION/SIGNIFICANCE: Our analysis provides evidence that the fecal microbiomes of wild primates co-vary with their hosts, and that this is manifested in higher intraspecies similarity among wild primate species, perhaps reflecting species

  12. Masticatory-stress hypotheses and the supraorbital region of primates. (United States)

    Hylander, W L; Picq, P G; Johnson, K R


    The purpose of this study is to test various masticatory-stress hypotheses about the evolution and function of well-developed browridges of higher primates. This was done by measuring and analyzing patterns of in vivo bone strain recorded from three-element rosette strain gages bonded to the supraorbital region and to other portions of the bony face of Macaca fascicularis and Papio anubis during mastication and incision. The magnitude and direction of the principal strains recorded support Endo's hypothesis that the supraorbital region during mastication and incision is bent in the frontal plane (Endo, 1966). Our data do not, however, support his hypothesis that the supraorbital region is bent more during incision than during mastication. The data also demonstrate that overall levels of supraorbital strain are not larger in more prognathic subjects. Most importantly, the data indicate that the supraorbital region of nonhuman catarrhines is strained very little during mastication and incision. This indicates that there is much more supraorbital bone than is necessary both to counter masticatory loads and to provide an adequate safety factor to failure for these loads. This in turn suggests that the macaque and baboon browridges can be considerably reduced in size and still maintain these required structural characteristics. Thus, our experiments provide no support whatsoever for those hypotheses that directly link browridge morphology to masticatory stress (cf. Endo, 1966; Russell, 1983, 1985). A recent review of Endo's original work indicates that this latter statement is also true for humans (Picq and Hylander, 1989). We conclude, therefore, that there is no good reason to believe that enlarged browridges in living and/or fossil primates are structural adaptations to counter intense masticatory forces. The evolution of browridge morphology in primates is best explained on the basis of factors related to the position of the brain relative to the orbits (Moss and

  13. Assessment of tropism and effectiveness of new primate-derived hybrid recombinant AAV serotypes in the mouse and primate retina.

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    Peter Charbel Issa

    Full Text Available Adeno-associated viral vectors (AAV have been shown to be safe in the treatment of retinal degenerations in clinical trials. Thus, improving the efficiency of viral gene delivery has become increasingly important to increase the success of clinical trials. In this study, structural domains of different rAAV serotypes isolated from primate brain were combined to create novel hybrid recombinant AAV serotypes, rAAV2/rec2 and rAAV2/rec3. The efficacy of these novel serotypes were assessed in wild type mice and in two models of retinal degeneration (the Abca4(-/- mouse which is a model for Stargardt disease and in the Pde6b(rd1/rd1 mouse in vivo, in primate tissue ex-vivo, and in the human-derived SH-SY5Y cell line, using an identical AAV2 expression cassette. We show that these novel hybrid serotypes can transduce retinal tissue in mice and primates efficiently, although no more than AAV2/2 and rAAV2/5 serotypes. Transduction efficiency appeared lower in the Abca4(-/- mouse compared to wild type with all vectors tested, suggesting an effect of specific retinal diseases on the efficiency of gene delivery. Shuffling of AAV capsid domains may have clinical applications for patients who develop T-cell immune responses following AAV gene therapy, as specific peptide antigen sequences could be substituted using this technique prior to vector re-treatments.

  14. Diagnostic overview of the illegal trade in primates and law enforcement in Peru. (United States)

    Shanee, Noga; Mendoza, A Patricia; Shanee, Sam


    Peru has one of the richest primate faunas of any country. The illegal trade in wild primates is one of the largest threats to this fauna in Peru. We characterize the illegal trade in primates through empirical and ethnographic data. We collected data from traffic routes and centers throughout Peru and evaluate current efforts to combat this traffic. Based on our findings from 2,070 instances of wildlife crime involving 6,872 primates, we estimate the domestic trade in primates for pets and bushmeat in Peru in the hundreds of thousands per year, with the larger bodied Atelidae facing the highest direct consequences. We found that government authorities lack sufficient staff, capacity, resources, infrastructure, and protocols to efficiently combat illegal trade in primates. Also, the complicated legal framework and lack of cooperation and antagonism with the public further limit these efforts. Wildlife authorities in Peru are able to confiscate only a fraction of primates traded and mostly intervene in cases of private pet owners rather than traffickers. We estimate that the current rate of illegal trade in primates is comparable to levels of trade prior to the 1973 ban on primates' exportation. The combination of direct observations on primate trade and ethnographic data allows a comprehensive look at primate trade in Peru. We call upon decision makers and international funders to channel their efforts toward "on the ground" actions such as increasing the ability of the authorities to act, giving them "in action" training in law enforcement and establishing strict control measures against corruption. Am. J. Primatol. 79:e22516, 2017. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

  15. A new avian fauna from the early-middle Eocene Lillebælt Clay Formation of Denmark

    DEFF Research Database (Denmark)

    Lindow, Bent Erik Kramer

    A number of hitherto undescribed fossil bird remains have been recovered from the Lillebælt Clay Formation of central Denmark, which is early-middle Eocene in age (~50 to 43 mya). The core of the material consists of fossils acquired through the Danish ‘Danekræ' fossil treasure trove legislation....... Almost two-thirds of the fossils are isolated skulls preserved three-dimensionally in clay ironstone concretions; bird fossils of this age and degree of preservation are extremely rare in an international context. A preliminary investigation has revealed the presence of at least one odontopterygid......, a member of the extinct 'pseudo-toothed birds' and the first representative of this group known from Denmark. Other taxa present include remains of Lithornithidae and a new taxon possessing a massive, psittacid-like beak. The Lillebælt Clay Formation birds are temporally placed just after the Early Eocene...

  16. The Eocene-Oligocene transition in the North Alpine Foreland Basin and subsequent closure of a Paratethys gateway (United States)

    van der Boon, A.; Beniest, A.; Ciurej, A.; Gaździcka, E.; Grothe, A.; Sachsenhofer, R. F.; Langereis, C. G.; Krijgsman, W.


    During the Eocene-Oligocene transition (EOT), a major palaeoenvironmental change took place in the Paratethys Sea of central Eurasia. Restricted connectivity and increased stratification resulted in wide-spread deposition of organic-rich sediments which nowadays make up important hydrocarbon source rocks. The North Alpine Foreland Basin (NAFB) was a major gateway of the Paratethys Sea to the open ocean during the Eocene, but the age of closure of this gateway is still uncertain. The Ammer section in southern Germany documents the shallowing of this connection and subsequent disappearance of marine environments in the NAFB, as reflected in its sedimentary succession of turbidites to marls (Deutenhausen to Tonmergel beds), via coastal sediments (Baustein beds) to continental conglomerates (Weißach beds). Here, we apply organic geochemistry and date the lithological transitions in the Ammer section using integrated stratigraphy, including magnetostratigraphy and biostratigraphy. Nannoplankton and dinocyst results can be reconciled when dinoflagellate species Wetzeliella symmetrica is of late Eocene age. Our magnetostratigraphy then records C13r-C13n-C12r and allows calculation of sediment accumulation rates and estimation of ages of lithological transitions. We show that the shallowing from turbiditic slope deposits (Deutenhausen beds) to shelf sediments (Tonmergel beds) coincides with the Eocene-Oligocene boundary at 33.9 Ma. The transition to continental sediments is dated at ca. 33.15 Ma, significantly older than suggested by previous studies. We conclude that the transition from marine to continental sediments drastically reduced the marine connection through the western part of the NAFB and influenced the oxygen conditions of the Paratethys Sea.

  17. Trace fossils from the eocene Lillebælt clay formation, Røsnæs Peninsula, Denmark


    Nielsen, Jan Kresten; Milàn, Jesper; Mesfun, Daniel


    A cliff exposure of the Eocene Lillebælt Clay Formation, on the Røsnæs peninsula of Zealand, Denmark, has yielded a diverse trace-fossil assemblage. The trace fossils are described formally for the first time and assigned to Phymatoderma melvillensis, unnamed clusters of small burrows, Ophiomorpha nodosa, Spongeliomorpha isp., Dreginozoum beckumensis, Bichordites isp., Chondrites isp., Atollites zitteli? and ?Rhizocorallium isp. The preservation of the trace fossils is strongly related to ear...

  18. Probable aestivation burrows from the Eocene/Oligocene transition in south-eastern France and their palaeoenvironmental implications


    Gaillard, Christian; Olivero, Davide; Chebance, Marie


    International audience; Enigmatic biogenic structures are reported from the Palaeogene of south-eastern France in the Castellane-Blieux area (Alpes de Haute-Provence French Department). They occur at the Eocene/Oligocene transition at the top of the Marnes Bleues Formation, which corresponds to a clearly defined regressive sequence, where thick marls are overlain by lacustrine limestones or sandstones. The marls have abundant shallow marine fauna and the upper part of the Formation correspond...

  19. Primate disease ecology in comparative and theoretical perspective. (United States)

    Nunn, Charles L


    Infectious disease plays a major role in the lives of wild primates, and the past decade has witnessed significant strides in our understanding of primate disease ecology. In this review, I briefly describe some key findings from phylogenetic comparative approaches, focusing on analyses of parasite richness that use the Global Mammal Parasite Database. While these studies have provided new answers to fundamental questions, new questions have arisen, including questions about the underlying epidemiological mechanisms that produce the broader phylogenetic patterns. I discuss two examples in which theoretical models have given us new traction on these comparative questions. First, drawing on findings of a positive association between range use intensity and the richness of helminth parasites, we developed a spatially explicit agent-based model to investigate the underlying drivers of this pattern. From this model, we are gaining deeper understanding of how range use intensity results in greater exposure to parasites, thus producing higher prevalence in the simulated populations-and, plausibly, higher parasite richness in comparative analyses. Second, I show how a model of disease spread on social networks provides solid theoretical foundations for understanding the effects of sociality and group size on parasitism across primate species. This study further revealed that larger social groups are more subdivided, which should slow the spread of infectious diseases. This effect could offset the increased disease risk expected in larger social groups, which has yet to receive strong empirical support in our comparative analyses. In addition to these examples, I discuss the need for more meta-analyses of individual-level phenomena documented in the field, and for greater linkage between theoretical modeling and field research. © 2012 Wiley Periodicals, Inc.

  20. Considering the Influence of Nonadaptive Evolution on Primate Color Vision.

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    Rachel L Jacobs

    Full Text Available Color vision in primates is variable across species, and it represents a rare trait in which the genetic mechanisms underlying phenotypic variation are fairly well-understood. Research on primate color vision has largely focused on adaptive explanations for observed variation, but it remains unclear why some species have trichromatic or polymorphic color vision while others are red-green color blind. Lemurs, in particular, are highly variable. While some species are polymorphic, many closely-related species are strictly dichromatic. We provide the first characterization of color vision in a wild population of red-bellied lemurs (Eulemur rubriventer, Ranomafana National Park, Madagascar with a sample size (87 individuals; NX chromosomes = 134 large enough to detect even rare variants (0.95 probability of detection at ≥ 3% frequency. By sequencing exon 5 of the X-linked opsin gene we identified opsin spectral sensitivity based on known diagnostic sites and found this population to be dichromatic and monomorphic for a long wavelength allele. Apparent fixation of this long allele is in contrast to previously published accounts of Eulemur species, which exhibit either polymorphic color vision or only the medium wavelength opsin. This unexpected result may represent loss of color vision variation, which could occur through selective processes and/or genetic drift (e.g., genetic bottleneck. To indirectly assess the latter scenario, we genotyped 55 adult red-bellied lemurs at seven variable microsatellite loci and used heterozygosity excess and M-ratio tests to assess if this population may have experienced a recent genetic bottleneck. Results of heterozygosity excess but not M-ratio tests suggest a bottleneck might have occurred in this red-bellied lemur population. Therefore, while selection may also play a role, the unique color vision observed in this population might have been influenced by a recent genetic bottleneck. These results emphasize the

  1. Different responses to reward comparisons by three primate species.

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    Hani D Freeman

    Full Text Available Recently, much attention has been paid to the role of cooperative breeding in the evolution of behavior. In many measures, cooperative breeders are more prosocial than non-cooperatively breeding species, including being more likely to actively share food. This is hypothesized to be due to selective pressures specific to the interdependency characteristic of cooperatively breeding species. Given the high costs of finding a new mate, it has been proposed that cooperative breeders, unlike primates that cooperate in other contexts, should not respond negatively to unequal outcomes between themselves and their partner. However, in this context such pressures may extend beyond cooperative breeders to other species with pair-bonding and bi-parental care.Here we test the response of two New World primate species with different parental strategies to unequal outcomes in both individual and social contrast conditions. One species tested was a cooperative breeder (Callithrix spp. and the second practiced bi-parental care (Aotus spp.. Additionally, to verify our procedure, we tested a third confamilial species that shows no such interdependence but does respond to individual (but not social contrast (Saimiri spp.. We tested all three genera using an established inequity paradigm in which individuals in a pair took turns to gain rewards that sometimes differed from those of their partners.None of the three species tested responded negatively to inequitable outcomes in this experimental context. Importantly, the Saimiri spp responded to individual contrast, as in earlier studies, validating our procedure. When these data are considered in relation to previous studies investigating responses to inequity in primates, they indicate that one aspect of cooperative breeding, pair-bonding or bi-parental care, may influence the evolution of these behaviors. These results emphasize the need to study a variety of species to gain insight in to how decision-making may

  2. Introducing fecal stable isotope analysis in primate weaning studies. (United States)

    Reitsema, Laurie J


    This research investigates the potential of a new, noninvasive method for determining age of weaning among primates using stable carbon and nitrogen isotope ratios in feces. Analysis of stable isotope ratios in body tissues is a well-established method in archeology and ecology for reconstructing diet. This is the first study to investigate weaning in primates using fecal stable isotope ratios. Diets of a single François' langur (Trachypithecus francoisi) mother-infant pair at the Toledo Zoo are reconstructed using this technique to track changes in infant suckling behavior over the weaning period. Stable isotope ratios in feces are sampled instead of more traditional samples such as bone or hair to enable daily, noninvasive snapshots of weaning status. Isotopic assessments of weaning status are compared to visual assessments to identify any discordance between the two. Three measurements documented the transition from breast milk to solid foods: stable carbon isotope ratios (δ(13)C), stable nitrogen isotope ratios (δ(15)N), and nitrogen content of feces (%N). It appears that solid foods were introduced at approximately 2 months of infant age, but that nursing continued into the 12th month, when sample collection ceased. Stable isotope data exposed a much longer weaning period than what was expected based on previously published data for captive langurs, and clarified visual estimates of weaning status. This reflects the method's sensitivity to suckling at night and ability to distinguish actual nursing from comfort nursing. After testing this method with zoo animals, it can readily be applied among wild populations. An isotopic approach to weaning provides a new, accurate, and biologically meaningful assessment of interbirth intervals, and facilitates a better understanding of mother-infant interactions. Both of these outcomes are critical for developing successful conservation strategies for captive and wild primates. © 2012 Wiley Periodicals, Inc.

  3. Sistemas de apareamiento en un primate neotropical (Alouatta caraya

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    Oklander, Luciana


    Full Text Available La socioecología de primates no humanos provee un marco para comprender la evolución de varios aspectos de la conducta de nuestros antepasados. Un aspecto relevante de la evolución de los sistemas sociales es la descripción de los sistemas de apareamiento, que dependen de una combinación de estudios genéticos y comportamentales. Los estudios genéticomoleculares, en particular los STRs han permitido dilucidar sistemas de apareamiento y detallar el éxito reproductivo de los individuos. En platirrinos es necesario desarrollar STRs específicos. En el presente trabajo se detectaron STRs para Alouatta caraya. Estos monos aulladores habitan en el Noreste de nuestro país y países limítrofes, y sus tropas pueden tener uno o varios machos adultos. Se espera que el rango del macho juegue un papel importante en el acceso a hembras. Sin embargo, en varias especies de primates las hembras son promiscuas. Varias hipótesis explicarían este comportamiento desde asegurarse la fertilización, hasta evitar el infanticidio. Los objetivos del estudio fueron determinar si las jerarquías de dominancia entre machos se reflejan en un mayor acceso a cópulas y en la paternidad de las crías. Los resultados muestran que los machos dominantes obtuvieron un mayor número de cópulas (p<0,05, aunque las hembras copularon con varios machos de su tropa y tropas vecinas. La determinación de la paternidad de las crías permitirá dilucidar el sistema de apareamiento de estos primates.

  4. Endocrine and Local Control of the Primate Corpus Luteum (United States)

    Stouffer, Richard L.; Bishop, Cecily V.; Bogan, Randy L.; Xu, Fuhua; Hennebold, Jon D.


    The primate corpus luteum is a transient endocrine gland that differentiates from the ovulatory follicle midway through the ovarian (menstrual) cycle. Its formation and limited lifespan is critical for fertility, as luteal-derived progesterone is the essential steroid hormone required for embryo implantation and maintenance of intra-uterine pregnancy until the placenta develops. It is well-established that LH and the LH-like hormone, CG, are the vital luteotropic hormones during the menstrual cycle and early pregnancy, respectively. Recent advances, particularly through genome analyses and cellular studies, increased our understanding of various local factors and cellular processes associated with the development, maintenance and repression of the corpus luteum. These include paracrine or autocrine factors associated with angiogenesis (e.g., VEGF), and that mediate LH/CG actions (e.g., progesterone), or counteract luteotropic effects (i.e., local luteolysis; e.g., PGF2α). However, areas of mystery and controversy remain, particularly regarding the signals and events that initiate luteal regression in the non-fecund cycle. Novel approaches capable of gene “knockdown” or amplification”, in vivo as well as in vitro, should identify novel or underappreciated gene products that are regulated by or modulate LH/CG actions to control the functional lifespan of the primate corpus luteum. Further advances in our understanding of luteal physiology will help to improve or control fertility for purposes ranging from preservation of endangered primate species to designing novel ovary-based contraceptives and treating ovarian disorders in women. R01 HD020869, R01 HD042000, U54 HD018185, U54 HD055744, P51 OD011092, T32 HD007133, Bayer Schering Pharma AG. PMID:24287034

  5. Astronomically paced changes in deep-water circulation in the western North Atlantic during the middle Eocene (United States)

    Vahlenkamp, Maximilian; Niezgodzki, Igor; De Vleeschouwer, David; Bickert, Torsten; Harper, Dustin; Kirtland Turner, Sandra; Lohmann, Gerrit; Sexton, Philip; Zachos, James; Pälike, Heiko


    North Atlantic Deep Water (NADW) currently redistributes heat and salt between Earth's ocean basins, and plays a vital role in the ocean-atmosphere CO2 exchange. Despite its crucial role in today's climate system, vigorous debate remains as to when deep-water formation in the North Atlantic started. Here, we present datasets from carbonate-rich middle Eocene sediments from the Newfoundland Ridge, revealing a unique archive of paleoceanographic change from the progressively cooling climate of the middle Eocene. Well-defined lithologic alternations between calcareous ooze and clay-rich intervals occur at the ∼41-kyr beat of axial obliquity. Hence, we identify obliquity as the driver of middle Eocene (43.5-46 Ma) Northern Component Water (NCW, the predecessor of modern NADW) variability. High-resolution benthic foraminiferal δ18O and δ13C suggest that obliquity minima correspond to cold, nutrient-depleted, western North Atlantic deep waters. We thus link stronger NCW formation with obliquity minima. In contrast, during obliquity maxima, Deep Western Boundary Currents were weaker and warmer, while abyssal nutrients were more abundant. These aspects reflect a more sluggish NCW formation. This obliquity-paced paleoceanographic regime is in excellent agreement with results from an Earth system model, in which obliquity minima configurations enhance NCW formation.

  6. Eocene high-latitude temperature gradients over time and space based on d18O values of fossil shark teeth (United States)

    Zeichner, S. S.; Kim, S.; Colman, A. S.


    Early-Mid Eocene (56.0-33.9Mya) is characterized by a temperate Antarctic climate and shallower latitudinal temperature gradients than those in present day. The warmer waters off the coast of the Antarctic Peninsula provided suitable habitats for taxa (i.e., sharks) that live today at lower latitudes. Stable isotope analysis of Eocene shark teeth provides a proxy to understand high latitude temperature gradients. However, shark ecology, in particular migration and occupation of tidal versus pelagic habitats, must be considered in the interpretation of stable isotope data. In this study, we analyze d18OPO4 values from the enameloid of Striatolamia (synonymized with Carcharias) shark teeth from the La Meseta formation (Seymour Island, Antarctica) to estimate paleotemperature in Early-Mid Eocene Antarctica, and assess the impact of ecology versus environmental signals on d18OPO4 values. We compare the ranges and offsets between our measured shark tooth d18OPO4 and published bivalve d18OCO3 values to test whether shark teeth record signals of migration across latitudinal temperature gradients, or instead reflect seasonal and long-term temporal variation across La Meseta stratigraphic units.

  7. Earliest Mysticete from the Late Eocene of Peru Sheds New Light on the Origin of Baleen Whales. (United States)

    Lambert, Olivier; Martínez-Cáceres, Manuel; Bianucci, Giovanni; Di Celma, Claudio; Salas-Gismondi, Rodolfo; Steurbaut, Etienne; Urbina, Mario; de Muizon, Christian


    Although combined molecular and morphological analyses point to a late middle Eocene (38-39 million years ago) origin for the clade Neoceti (Odontoceti, echolocating toothed whales plus Mysticeti, baleen whales, and relatives), the oldest known mysticete fossil dates from the latest Eocene (about 34 million years ago) of Antarctica [1, 2]. Considering that the latter is not the most stemward mysticete in recent phylogenies and that Oligocene toothed mysticetes display a broad morphological disparity most likely corresponding to contrasted ecological niches, the origin of mysticetes from a basilosaurid ancestor and its drivers are currently poorly understood [1, 3-8]. Based on an articulated cetacean skeleton from the early late Eocene (Priabonian, around 36.4 million years ago) of the Pisco Basin, Peru, we describe a new archaic tooth-bearing mysticete, Mystacodon selenensis gen. et sp. nov. Being the geologically oldest neocete (crown group cetacean) and the earliest mysticete to branch off described so far, the new taxon is interpreted as morphologically intermediate between basilosaurids and later toothed mysticetes, providing thus crucial information about the anatomy of the skull, forelimb, and innominate at these critical initial stages of mysticete evolution. Major changes in the morphology of the oral apparatus (including tooth wear) and flipper compared to basilosaurids suggest that suction and possibly benthic feeding represented key, early ecological traits accompanying the emergence of modern filter-feeding baleen whales' ancestors. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Cocaine is pharmacologically active in the nonhuman primate fetal brain

    DEFF Research Database (Denmark)

    Benveniste, Helene; Fowler, Joanna S; Rooney, William D


    -trimester pregnant nonhuman primates, cocaine at doses typically used by drug abusers significantly increased brain glucose metabolism to the same extent in the mother as in the fetus (approximately 100%). Inasmuch as brain glucose metabolism is a sensitive marker of brain function, the current findings provide...... evidence that cocaine use by a pregnant mother will also affect the function of the fetal brain. We are also unique in showing that cocaine's effects in brain glucose metabolism differed in pregnant (increased) and nonpregnant (decreased) animals, which suggests that the psychoactive effects of cocaine...

  9. Primate pulpal healing after exposure and TheraCal application. (United States)

    Cannon, Mark; Gerodias, Nate; Viera, Ana; Percinoto, Celio; Jurado, Ray


    The purpose of this in vivo study was to compare the effectiveness of a new light cured resin based dicalcium/tricalcium silicate pulp capping material (TheraCalLC, Bisco), pure Portland cement, resin based calcium hydroxide or glass ionomer in the healing of bacterially contaminated primate pulps. The experiment required four primates each having 12 teeth prepared with buccal penetrations into the pulpal tissues with an exposure of approximately 1.0 mm. The exposed pulps of the primate teeth were covered with cotton pellets soaked in a bacterial mixture consisting of microorganisms normally found in human pulpal abscesses. After removal of the pellet, hemostasis was obtained and the pulp capping agents applied. The light cured resin based pulp capping material (TheraCal LC) was applied to the pulpal tissue of twelve teeth with a needle tip syringe and light cured for 15 seconds. Pure Portland cement mixed with a 2% Chlorhexidine solution was placed on the exposed pulpal tissues of another twelve teeth. Twelve additional teeth had a base of GIC applied (Triage, Fuji VII GC America) and another twelve had a pulp cap with VLC DYCAL (Dentsply), a light cured calcium hydroxide resin based material. The pulp capping bases were then covered with a RMGI (Fuji II LC GC America). The tissue samples were collected at 4 weeks. The samples were deminerilized, sectioned, stained and histologically graded. There were no statistically significant differences between the groups in regard to pulpal inflammation (H = 0.679, P = 1.00). However, both the Portland cement and light cured TheraCal LC groups had significantly more frequent hard tissue bridge formation at 28 days than the GIC and VLC Dycal groups (H = 11.989, P = 0.009). The measured thickness of the hard tissue bridges with the pure Portland and light cured TheraCal LC groups were statistically greater than that of the other two groups (H = 15.849, P = 0.002). In addition, the occurrence of pulpal necrosis was greater

  10. Evolution of the Central Sulcus Morphology in Primates


    Hopkins, William D.; Meguerditchian, Adrien; Coulon, Olivier; Bogart, Stephanie; Mangin, Jean- François; Sherwood, Chet C.; Grabowski, Mark W.; Bennett, Allyson J.; Pierre, Peter J.; Fears, Scott; Woods, Roger; Hof, Patrick R.; Vauclair, Jacques


    The central sulcus (CS) divides the pre- and post-central gyri along the dorsal-ventral plane of which all motor and sensory functions are topographically organized. The motor-hand area of the precentral gyrus or knob has been described as the anatomical substrate of the hand in humans. Given the importance of the hand in primate evolution, here we examined the evolution of the motor-hand area by comparing the relative size and pattern of cortical folding of the CS surface area from magnetic ...

  11. Radiation dosimetry of [18F]VAT in nonhuman primates


    Karimi, Morvarid; Tu, Zhude; Yue, Xuyi; Zhang, Xiang; Jin, Hongjun; Perlmutter, Joel S.; Laforest, Richard


    Background The objective of this study is to determine the radiation dosimetry of a novel radiotracer for vesicular acetylcholine transporter (?)-(1-((2R,3R)-8-(2-[18F]fluoro-ethoxy)-3-hydroxy-1,2,3,4-tetrahydronaphthalen-2-yl)piperidin-4-yl)(4-fluorophenyl)-methanone ([18F]VAT) based on PET imaging in nonhuman primates. [18F]VAT has potential for investigation of neurological disorders including Alzheimer?s disease, Parkinson?s disease, and dystonia. Methods Three macaque fascicularis (two m...

  12. Productivity response of calcareous nannoplankton to Eocene Thermal Maximum 2 (ETM2

    Directory of Open Access Journals (Sweden)

    M. Dedert


    Full Text Available The Early Eocene Thermal Maximum 2 (ETM2 at ~53.7 Ma is one of multiple hyperthermal events that followed the Paleocene-Eocene Thermal Maximum (PETM, ~56 Ma. The negative carbon excursion and deep ocean carbonate dissolution which occurred during the event imply that a substantial amount (103 Gt of carbon (C was added to the ocean-atmosphere system, consequently increasing atmospheric CO2(pCO2. This makes the event relevant to the current scenario of anthropogenic CO2 additions and global change. Resulting changes in ocean stratification and pH, as well as changes in exogenic cycles which supply nutrients to the ocean, may have affected the productivity of marine phytoplankton, especially calcifying phytoplankton. Changes in productivity, in turn, may affect the rate of sequestration of excess CO2 in the deep ocean and sediments. In order to reconstruct the productivity response by calcareous nannoplankton to ETM2 in the South Atlantic (Site 1265 and North Pacific (Site 1209, we employ the coccolith Sr/Ca productivity proxy with analysis of well-preserved picked monogeneric populations by ion probe supplemented by analysis of various size fractions of nannofossil sediments by ICP-AES. The former technique of measuring Sr/Ca in selected nannofossil populations using the ion probe circumvents possible contamination with secondary calcite. Avoiding such contamination is important for an accurate interpretation of the nannoplankton productivity record, since diagenetic processes can bias the productivity signal, as we demonstrate for Sr/Ca measurements in the fine (<20 μm and other size fractions obtained from bulk sediments from Site 1265. At this site, the paleoproductivity signal as reconstructed from the Sr/Ca appears to be governed by cyclic changes, possibly orbital forcing, resulting in a 20–30% variability in Sr/Ca in dominant genera as obtained by ion probe. The ~13 to 21

  13. Sensitivity of the Eocene climate to CO2 and orbital variability (United States)

    Keery, John S.; Holden, Philip B.; Edwards, Neil R.


    The early Eocene, from about 56 Ma, with high atmospheric CO2 levels, offers an analogue for the response of the Earth's climate system to anthropogenic fossil fuel burning. In this study, we present an ensemble of 50 Earth system model runs with an early Eocene palaeogeography and variation in the forcing values of atmospheric CO2 and the Earth's orbital parameters. Relationships between simple summary metrics of model outputs and the forcing parameters are identified by linear modelling, providing estimates of the relative magnitudes of the effects of atmospheric CO2 and each of the orbital parameters on important climatic features, including tropical-polar temperature difference, ocean-land temperature contrast, Asian, African and South (S.) American monsoon rains, and climate sensitivity. Our results indicate that although CO2 exerts a dominant control on most of the climatic features examined in this study, the orbital parameters also strongly influence important components of the ocean-atmosphere system in a greenhouse Earth. In our ensemble, atmospheric CO2 spans the range 280-3000 ppm, and this variation accounts for over 90 % of the effects on mean air temperature, southern winter high-latitude ocean-land temperature contrast and northern winter tropical-polar temperature difference. However, the variation of precession accounts for over 80 % of the influence of the forcing parameters on the Asian and African monsoon rainfall, and obliquity variation accounts for over 65 % of the effects on winter ocean-land temperature contrast in high northern latitudes and northern summer tropical-polar temperature difference. Our results indicate a bimodal climate sensitivity, with values of 4.36 and 2.54 °C, dependent on low or high states of atmospheric CO2 concentration, respectively, with a threshold at approximately 1000 ppm in this model, and due to a saturated vegetation-albedo feedback. Our method gives a quantitative ranking of the influence of each of the

  14. Sequence stratigraphic analysis of Eocene Rock Strata, Offshore Indus, southwest Pakistan (United States)

    Khan, Natasha; Rehman, Khaista; Ahmad, Sajjad; Khokher, Jamil; Hajana, M. Iqbal; Hanif, M.


    In this study, seismic data from two wells (Pak G2-1 and Indus Marine-1C) and age diagnostic larger benthic foraminifera (LBF) within drill cuttings has been used for the first time to identify depositional sequences within the carbonates in the Offshore Indus Basin, Pakistan. The Offshore Indus is tectonically categorized as a passive continental margin where carbonates occur as shelf carbonates in the near offshore and on volcanic seamounts in deeper waters. Seismic data analysis has indicated the presence of minor faults and carbonate buildups above the igneous basement in the south. Patterns of the seismic reflections enabled definition of three seismic facies units identified as: Unit 1 basement, represented by chaotic, moderate amplitude reflection configuration; while parallel bedding and the drape of overlying strata is typical character of Unit 2, carbonate mound facies. The younger Miocene channels represent Unit 3. The diagnosis of Alveolina vredenburgi/cucumiformis biozone confirmed the Ilerdian (55-52 Ma) stage constituting a second order cycle of deposition for the Eocene carbonates (identified as Unit 2). The carbonate succession has been mainly attributed to an early highstand system tract (HST). The environmental conditions remained favorable leading to the development of keep-up carbonates similar to pinnacle buildups as a result of aggradation during late transgressive system tract and an early HST. The carbonate sequence in the south (Pak G2-1) is thicker and fossiliferous representing inner to middle shelf depths based on fauna compared to the Indus Marine-1C in the north, which is devoid of fossils. Three biozones (SBZ 5, SBZ 6 and SBZ 8) were identified based on the occurrence of LBF. The base of the SBZ 5 zone marks the larger foraminifera turnover and the Paleocene-Eocene (P-E) boundary. The LBF encountered in this study coincides with earlier findings for the P-E boundary. Our findings indicate that the entire Ilerdian stage ranges from 55

  15. Fluvial-system response to climate change: The Paleocene-Eocene Tremp Group, Pyrenees, Spain (United States)

    Colombera, Luca; Arévalo, Oscar J.; Mountney, Nigel P.


    The Tremp Group of the Tremp-Graus Basin (Southern Pyrenees, Spain) is a succession of predominantly continental origin that records the Paleocene-Eocene Thermal Maximum (PETM), a transient episode of extreme global warming that occurred across the Paleocene-Eocene boundary. For this succession, the stratigraphic position of the PETM is accurately determined, and histories of tectonic and sea-level controls are well constrained. Building upon previous studies, this work assesses changes in sedimentary architecture through the PETM in the Tremp Group, based on quantitative sedimentological analyses documented over a km-scale strike-oriented transect in the Arén area, with the scope to better understand the response of this alluvial system to the hyperthermal event. The analysed features represent a partial record of the geomorphic organization and processes of the system at the time of deposition, and are therefore interpretable in terms of geomorphic change in alluvial landscapes caused by the PETM. The record of the PETM, as previously recognized, begins at a time when erosional palaeotopographic relief was developed and deposition was confined in valleys. A shift between valley back-filling and widespread aggradation is observed at the onset of the PETM interval, which demonstrates uniquely the impact of the hyperthermal on both depositional loci and interfluves. Compared to underlying strata, the interval that embodies the onset and main phase of the PETM is characterized by: (i) higher proportion of channel deposits; (ii) channel complexes of greater average thickness and width; (iii) barforms and channel fills that are slightly thicker; (iv) increased thickness of sets of cross-stratified sandstones; (v) similar values of maximum extraclast size, by architectural element. An evident change in the facies organization of channel deposits is also seen through the stratigraphy, though this appears to predate the PETM. Increased channel-body density in the PETM

  16. Sub-Milankovitch millennial-scale climate variability in Middle Eocene deep-marine sediments (United States)

    Scotchman, J. I.; Pickering, K. T.; Robinson, S. A.


    Sub-Milankovitch millennial scale climate variability appears ubiquitous throughout the Quaternary and Pleistocene palaeoenvironmental records (e.g. McManus et al., 1999) yet the driving mechanism remains elusive. Possible mechanisms are generally linked to Quaternary-specific oceanic and cryospheric conditions (e.g. Maslin et al., 2001). An alternative external control, such as solar forcing, however, remains a compelling alternative hypothesis (e.g. Bond et al., 2001). This would imply that millennial-scale cycles are an intrinsic part of the Earth’s climatic system and not restricted to any specific period of time. Determining which of these hypotheses is correct impacts on our understanding of the climate system and its role as a driver of cyclic sedimentation during both icehouse and greenhouse climates. Here we show that Middle Eocene, laminated deep-marine sediments deposited in the Ainsa Basin, Spanish Pyrenees, contain 1,565-year (469 mm) cycles modulated by a 7,141-year (2157 mm) period. Climatic oscillations of 1,565-years recorded by element/Al ratios, are interpreted as representing climatically driven variation in sediment supply (terrigenous run-off) to the Ainsa basin. Climatic oscillations with this period are comparable to Quaternary Bond (~1,500-year), Dansgaard-Oeschger (~1,470-year) and Heinrich (~7,200-year) climatic events. Recognition of similar millennial-scale oscillations in the greenhouse climate of the Middle Eocene would appear inconsistent with an origin dependent upon Quaternary-specific conditions. Our observations lend support for pervasive millennial-scale climatic variability present throughout geologic time likely driven by an external forcing mechanism such as solar forcing. References Bond, G., Kromer, B., Beer, J., Muscheler, R., Evans, M.N., Showers, W., Hoffmann, S., Lotti-Bond, R., Hajdas, I., Bonani, G. 2001. Persistent Solar Influence on North Atlantic Climate During the Holocene. Science, 294, 2130-2136 Maslin, M

  17. High resolution taxonomic study of the late Eocene (~34 Ma) Florissant palynoflora, Colorado, USA (United States)

    Bouchal, J. M.


    The Florissant Fossil Beds National Monument is located in Teller County in central Colorado, at approximate latitude 38°54'N and longitude 105°13'. The lithologies of the Florissant Formation consist of coarse-grained arkosic and volcanoclastic sandstones and conglomerates, finer shale, and tuffaceus mudstone and siltstone. It is divided into six units, mostly of lacustrine and fluvial origin with volcanic sediments interfingering and topping the strata. Volcanic units have been dated using the 40Ar/39Ar single-crystal method, giving an absolute age of ca. 34 Ma for the upper fossiliferous sedimentary unit. This pinpoints the formation of the Florissant sediments at the end of the Eocene, providing fruitful insight into the changing palaeoecosystem of the region at the dawn of the Oligocene. The formation is very well known for its rich fossil insect fauna and well preserved plant macrofossils found in the shale units, and the silicified tree stumps occurring in the lower mudstone unit. The sample used for this study originates from the upper shale unit, the fifth unit from the base of the formation. Previous studies on the plant macrofossils, mesofossils and the palynoflora have shown that during the late Eocene the surroundings of Florissant palaeo-lake were covered by diverse mixed broad-leaved evergreen/deciduous and needle-leafed forests. Until now pollen from the Florissant Formation has mostly been described according to conventional morphological nomenclature, using light microscopy (LM) only. In this study the same individual pollen grains are investigated using both LM and scanning electron microscopy (SEM), by means of single grain technique. This provides best exploitable results concerning a more detailed resolution regarding taxonomy and more accurate identifications. The main goal of this study is to compile a well resolved taxonomic species list based on the palynoflora, to clarify the generic and species diversity of selected families (e

  18. Paleocene-Eocene Paleoclimatic Event Records in the Chicxulub Crater (Yucatan, Gulf of Mexico) (United States)

    Perez-Cruz, L. L.; Fucugauchi, J. U.


    Chicxulub crater was formed by an asteroid impact on the Yucatan carbonate platform about 65.5 Ma ago at the Cretaceous/Paleogene (K/Pg) boundary. After crater formation, carbonate deposition gradually covered the structure, preserving a largely undisturbed sedimentary record for the Paleogene. As part of the studies, drilling programs with continuous core recovery have been conducted over the past years. The cores preserve a record of post-impact processes, life recovery in target area, platform evolution and emergence, sea-level changes and the paleoceanographic and paleoclimatic conditions in the region. To contribute to the knowledge of the Paleocene-Eocene warming and changes in oceanic hydrography, we carried out x-ray fluorescence and stable oxygen and carbon isotope studies of the carbonate sections on top of the impact breccias sampled in the Santa Elena and Yaxcopoil-1 boreholes. The Santa Elena borehole is located 110 km radial distance from crater center, outside the crater rim. Yaxcopoil-1 borehole is located 62 km away from crater center in the terrace zone inside the crater rim. The Cenozoic sequence is about 332 m and 796 m thick in the Santa Elena and Yaxcopoil-1 boreholes. The stable isotope records are correlated to data on marine sediment cores from the ocean drilling projects for the Paleocene and Eocene, which permit inferences on the paleoceanographic and paleoclimatic reconstruction as well as additional stratigraphic constraints for the sections. The positive bulk carbon isotope (δ13C) values in the basal Paleocene sediments reflect a return or enhancement of ocean productivity following plankton extinctions following the K/Pg impact. The Paleocene represents a time of global warmth temperatures with low vertical and latitudinal gradients in the oceans, likely resulting from elevated CO2 levels. δ13C values in the Santa Elena borehole show increases between 3 and 4 % by the late Paleocene that decrease to levels prevailing before the K

  19. Chicxulub Impact, Yucatan Carbonate Platform, Cretaceous-Paleogene Boundary and Paleocene-Eocene Thermal Maximum (United States)

    Fucugauchi, J. U.; Perez-Cruz, L. L.


    Chicxulub formed 66 Ma ago by an asteroid impact on the Yucatan carbonate platform, southern Gulf of Mexico. Impact produced a 200 km diameter crater, platform fracturing, deformation and ejecta emplacement. Carbonate sedimentation restarted and crater was covered by up to 1 km of sediments. Drilling programs have sampled the Paleogene sediments, which record the changing sedimentation processes in the impact basin and platform. Here, results of a study of the Paleocene-Eocene sediments cored in the Santa Elena borehole are used to characterize the K/Pg and PETM. The borehole reached a depth of 504 m and was continuously cored, sampling the post-impact sediments and impact breccias, with contact at 332 m. For this study, we analyzed the section from ~230 to ~340 m, corresponding to the upper breccias and Paleocene-Eocene sediments. The lithological column, constructed from macroscopic and thin-section petrographic analyses, is composed of limestones and dolomitized limestones with several thin clay layers. Breccias are melt and basement clast rich, described as a suevitic unit. Section is further investigated using paleomagnetic, rock magnetic, X-ray fluorescence geochemical and stable isotope analyses. Magnetic polarities define a sequence of reverse to normal, which correlate to the geomagnetic polarity time scale from chrons 29r to 26r. The d13 C values in the first 20 m interval range from 1.2 to 3.5 %0 and d18 O values range from -1.4 to -4.8 %0. Isotope values show variation trends that correlate with the marine carbon and oxygen isotope patterns for the K-Pg boundary and early Paleocene. Positive carbon isotopes suggest relatively high productivity, with apparent recovery following the K-Pg extinction event. Geochemical data define characteristic trends, with Si decreasing gradually from high values in the suevites, low contents in Paleocene sediments with intervals of higher variability and then increased values likely marking the PETM. Variation trends are

  20. Stable isotope and calcareous nannofossil assemblage record of the late Paleocene and early Eocene (Cicogna section) (United States)

    Agnini, Claudia; Spofforth, David J. A.; Dickens, Gerald R.; Rio, Domenico; Pälike, Heiko; Backman, Jan; Muttoni, Giovanni; Dallanave, Edoardo


    We present records of stable carbon and oxygen isotopes, CaCO3 content, and changes in calcareous nannofossil assemblages across an 81 m thick section of upper Paleocene-lower Eocene marine sedimentary rocks now exposed along the Cicogna Stream in northeast Italy. The studied stratigraphic section represents sediment accumulation in a bathyal hemipelagic setting from approximately 57.5 to 52.2 Ma, a multi-million-year time interval characterized by perturbations in the global carbon cycle and changes in calcareous nannofossil assemblages. The bulk carbonate δ13C profile for the Cicogna section, once placed on a common timescale, resembles that at several other locations across the world, and includes both a long-term drop in δ13C and multiple short-term carbon isotope excursions (CIEs). This precise correlation of widely separated δ13C records in marine sequences results from temporal changes in the carbon composition of the exogenic carbon cycle. However, diagenesis has likely modified the δ13C record at Cicogna, an interpretation supported by variations in bulk carbonate δ18O, which do not conform to expectations for a primary signal. The record of CaCO3 content reflects a combination of carbonate dilution and dissolution, as also inferred at other sites. Our detailed documentation and statistical analysis of calcareous nannofossil assemblages show major differences before, during and after the Paleocene-Eocene Thermal Maximum. Other CIEs in our lower Paleogene section do not exhibit such a distinctive change; instead, these events are sometimes characterized by variations restricted to a limited number of taxa and transient shifts in the relative abundance of primary assemblage components. Both long-lasting and short-lived modifications to calcareous nannofossil assemblages preferentially affected nannoliths or holococcoliths such as Discoaster, Fasciculithus, Rhomboaster/Tribrachiatus, Sphenolithus and Zygrhablithus, which underwent distinct variations in

  1. Mechanistic modelling of Middle Eocene atmospheric carbon dioxide using fossil plant material (United States)

    Grein, Michaela; Roth-Nebelsick, Anita; Wilde, Volker; Konrad, Wilfried; Utescher, Torsten


    Various proxies (such as pedogenic carbonates, boron isotopes or phytoplankton) and geochemical models were applied in order to reconstruct palaeoatmospheric carbon dioxide, partially providing conflicting results. Another promising proxy is the frequency of stomata (pores on the leaf surface used for gaseous exchange). In this project, fossil plant material from the Messel Pit (Hesse, Germany) is used to reconstruct atmospheric carbon dioxide concentration in the Middle Eocene by analyzing stomatal density. We applied the novel mechanistic-theoretical approach of Konrad et al. (2008) which provides a quantitative derivation of the stomatal density response (number of stomata per leaf area) to varying atmospheric carbon dioxide concentration. The model couples 1) C3-photosynthesis, 2) the process of diffusion and 3) an optimisation principle providing maximum photosynthesis (via carbon dioxide uptake) and minimum water loss (via stomatal transpiration). These three sub-models also include data of the palaeoenvironment (temperature, water availability, wind velocity, atmospheric humidity, precipitation) and anatomy of leaf and stoma (depth, length and width of stomatal porus, thickness of assimilation tissue, leaf length). In order to calculate curves of stomatal density as a function of atmospheric carbon dioxide concentration, various biochemical parameters have to be borrowed from extant representatives. The necessary palaeoclimate data are reconstructed from the whole Messel flora using Leaf Margin Analysis (LMA) and the Coexistence Approach (CA). In order to obtain a significant result, we selected three species from which a large number of well-preserved leaves is available (at least 20 leaves per species). Palaeoclimate calculations for the Middle Eocene Messel Pit indicate a warm and humid climate with mean annual temperature of approximately 22°C, up to 2540 mm mean annual precipitation and the absence of extended periods of drought. Mean relative air

  2. Enumeration of Objects and Substances in Non-Human Primates: Experiments with Brown Lemurs ("Eulemur Fulvus") (United States)

    Mahajan, Neha; Barnes, Jennifer L.; Blanco, Marissa; Santos, Laurie R.


    Both human infants and adult non-human primates share the capacity to track small numbers of objects across time and occlusion. The question now facing developmental and comparative psychologists is whether similar mechanisms give rise to this capacity across the two populations. Here, we explore whether non-human primates' object tracking…

  3. The Taiata mountain dwarf galago Galagoides sp: a new primate for ...

    African Journals Online (AJOL)

    Surveys in the forests of the Taita Hills yielded a new primate record for Kenya. Based on direct observations and tape recordings of its vocalizations, this primate is identified as a dwarf galago Galagoides sp. Identification to the species level is not possible at this stage as molecular data are not available, and more ...

  4. Effect of land use dynamics on habitat of two sympatric primates in ...

    African Journals Online (AJOL)

    Competition between growing human population and burgeoning number of primates were investigated at the Boabeng-Fiema monkey sanctuary (BFMS) in Ghana, to determine the effect of habitat change on primates. Remote sensing data, primarily Landsat imagery, were used to analyse the land use cover changes that ...

  5. [Does Alzheimer's disease exist in all primates? Alzheimer pathology in non-human primates and its pathophysiological implications (II)]. (United States)

    Toledano, A; Álvarez, M I; López-Rodríguez, A B; Toledano-Díaz, A; Fernández-Verdecia, C I


    In the ageing process there are some species of non-human primates which can show some of the defining characteristics of the Alzheimer's disease (AD) of man, both in neuropathological changes and cognitive-behavioural symptoms. The study of these species is of prime importance to understand AD and develop therapies to combat this neurodegenerative disease. In this second part of the study, these AD features are discussed in the most important non-experimental AD models (Mouse Lemur -Microcebus murinus, Caribbean vervet -Chlorocebus aethiops, and the Rhesus and stump-tailed macaque -Macaca mulatta and M. arctoides) and experimental models (lesional, neurotoxic, pharmacological, immunological, etc.) non-human primates. In all these models cerebral amyloid neuropathology can occur in senility, although with different levels of incidence (100% in vervets;Alzheimer's) senility in these species are difficult to establish due to the lack of cognitive-behavioural studies in the many groups analysed, as well as the controversy in the results of these studies when they were carried out. However, in some macaques, a correlation between a high degree of functional brain impairment and a large number of neuropathological changes ("possible AD") has been found. In some non-human primates, such as the macaque, the existence of a possible continuum between "normal" ageing process, "normal" ageing with no deep neuropathological and cognitive-behavioural changes, and "pathological ageing" (or "Alzheimer type ageing"), may be considered. In other cases, such as the Caribbean vervet, neuropathological changes are constant and quite marked, but its impact on cognition and behaviour does not seem to be very important. This does assume the possible existence in the human senile physiological regression of a stable phase without dementia even if neuropathological changes appeared. Copyright © 2011 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.

  6. Primate cognition: attention, episodic memory, prospective memory, self-control, and metacognition as examples of cognitive control in nonhuman primates. (United States)

    Beran, Michael J; Menzel, Charles R; Parrish, Audrey E; Perdue, Bonnie M; Sayers, Ken; Smith, J David; Washburn, David A


    Primate Cognition is the study of cognitive processes, which represent internal mental processes involved in discriminations, decisions, and behaviors of humans and other primate species. Cognitive control involves executive and regulatory processes that allocate attention, manipulate and evaluate available information (and, when necessary, seek additional information), remember past experiences to plan future behaviors, and deal with distraction and impulsivity when they are threats to goal achievement. Areas of research that relate to cognitive control as it is assessed across species include executive attention, episodic memory, prospective memory, metacognition, and self-control. Executive attention refers to the ability to control what sensory stimuli one attends to and how one regulates responses to those stimuli, especially in cases of conflict. Episodic memory refers to memory for personally experienced, autobiographical events. Prospective memory refers to the formation and implementation of future-intended actions, such as remembering what needs to be done later. Metacognition consists of control and monitoring processes that allow individuals to assess what information they have and what information they still need, and then if necessary to seek information. Self-control is a regulatory process whereby individuals forego more immediate or easier to obtain rewards for more delayed or harder to obtain rewards that are objectively more valuable. The behavioral complexity shown by nonhuman primates when given tests to assess these capacities indicates psychological continuities with human cognitive control capacities. However, more research is needed to clarify the proper interpretation of these behaviors with regard to possible cognitive constructs that may underlie such behaviors. WIREs Cogn Sci 2016, 7:294-316. doi: 10.1002/wcs.1397 For further resources related to this article, please visit the WIREs website. © 2016 Wiley Periodicals, Inc.

  7. Primate-specific Long Non-coding RNAs and MicroRNAs

    Directory of Open Access Journals (Sweden)

    Hassaan Mehboob Awan


    Full Text Available Non-coding RNAs (ncRNAs are critical regulators of gene expression in essentially all life forms. Long ncRNAs (lncRNAs and microRNAs (miRNAs are two important RNA classes possessing regulatory functions. Up to date, many primate-specific ncRNAs have been identified and investigated. Their expression specificity to primate lineage suggests primate-specific roles. It is thus critical to elucidate the biological significance of primate or even human-specific ncRNAs, and to develop potential ncRNA-based therapeutics. Here, we have summarized the studies regarding regulatory roles of some key primate-specific lncRNAs and miRNAs.

  8. A unified framework for the organisation of the primate auditory cortex

    Directory of Open Access Journals (Sweden)

    Simon eBaumann


    Full Text Available In nonhuman primates a scheme for the organisation of the auditory cortex is frequently used to localise auditory processes. The scheme allows a common basis for comparison of functional organisation across nonhuman primate species. However, although a body of functional and structural data in nonhuman primates supports an accepted scheme of nearly a dozen neighbouring functional areas, can this scheme be directly applied to humans? Attempts to expand the scheme of auditory cortical fields in humans have been severely hampered by a recent controversy about the organisation of tonotopic maps in humans, centred on two different models with radically different organisation. We point out observations that reconcile the previous models and suggest a distinct model in which the human cortical organisation is much more like that of other primates. This unified framework allows a more robust and detailed comparison of auditory cortex organisation across primate species including humans.

  9. Aging in the Natural World: Comparative Data Reveal Similar Mortality Patterns Across Primates (United States)

    Bronikowski, Anne M.; Altmann, Jeanne; Brockman, Diane K.; Cords, Marina; Fedigan, Linda M.; Pusey, Anne; Stoinski, Tara; Morris, William F.; Strier, Karen B.; Alberts, Susan C.


    Human senescence patterns—late onset of mortality increase, slow mortality acceleration, and exceptional longevity—are often described as unique in the animal world. Using an individual-based data set from longitudinal studies of wild populations of seven primate species, we show that contrary to assumptions of human uniqueness, human senescence falls within the primate continuum of aging; the tendency for males to have shorter life spans and higher age-specific mortality than females throughout much of adulthood is a common feature in many, but not all, primates; and the aging profiles of primate species do not reflect phylogenetic position. These findings suggest that mortality patterns in primates are shaped by local selective forces rather than phylogenetic history. PMID:21393544

  10. Salinity of the Early and Middle Eocene Arctic Ocean From Oxygen Isotope Analysis of Fish Bone Carbonate (United States)

    Waddell, L. M.; Moore, T. C.


    Plate tectonic reconstructions indicate that the Arctic was largely isolated from the world ocean during the early and middle Eocene, with exchange limited to shallow, and possibly intermittent, connections to the North Atlantic and Tethys (via the Turgay Strait). Relative isolation, combined with an intensification of the hydrologic cycle under an Eocene greenhouse climate, is suspected to have led to the development of a low- salinity surface water layer in the Arctic that could have affected deep and intermediate convection in the North Atlantic. Sediment cores recently recovered from the Lomonosov Ridge by the IODP 302 Arctic Coring Expedition (ACEX) allow for the first assessment of the salinity of the Arctic Ocean during the early and middle Eocene. Stable isotope analysis performed on the structural carbonate of fish bone apatite from ~30 samples between the ages of ~55 and ~44 myr yielded δ18O values between -6.84‰ and -2.96‰ VPDB, with a mean value of -4.89‰. From the δ18O values we calculate that the Arctic Ocean was probably brackish during most of the early and middle Eocene, with an average salinity of 19 to 24‰. Negative excursions in the δ18O record (<-6‰) indicate three events during which the salinity of the Arctic surface waters was severely lowered: the Paleocene Eocene Thermal Maximum (PETM), the Azolla event at ~49 Ma, and a third previously unidentified event at ~46 Ma. During the PETM, low salinities developed under conditions of increased regional precipitation and runoff associated with extreme high latitude warmth and possible tectonic uplift in the North Atlantic. During the other two low-salinity events, sea level was lowered by ~20-30 m, implying a possible severing of Arctic connections to the world ocean. The most positive δ18O value (-2.96‰) occurs at ~45 Ma, the age of the youngest dropstone discovered in the ACEX sediments, and may therefore correspond to a climatic cooling rather than a high salinity event.

  11. High resolution cyclostratigraphy of the early Eocene – new insights into the origin of the Cenozoic cooling trend

    Directory of Open Access Journals (Sweden)

    T. Westerhold


    Full Text Available Here we present a high-resolution cyclostratigraphy based on X-ray fluorescence (XRF core scanning data from a new record retrieved from the tropical western Atlantic (Demerara Rise, ODP Leg 207, Site 1258. The Eocene sediments from ODP Site 1258 cover magnetochrons C20 to C24 and show well developed cycles. This record includes the missing interval for reevaluating the early Eocene part of the Geomagnetic Polarity Time Scale (GPTS, also providing key aspects for reconstructing high-resolution climate variability during the Early Eocene Climatic Optimum (EECO. Detailed spectral analysis demonstrates that early Eocene sedimentary cycles are characterized by precession frequencies modulated by short (100 kyr and long (405 kyr eccentricity with a generally minor obliquity component. Counting of both the precession and eccentricity cycles results in revised estimates for the duration of magnetochrons C21r through C24n. Our cyclostratigraphic framework also corroborates that the geochronology of the Eocene Green River Formation (Wyoming, USA is still questionable mainly due to the uncertain correlation of the "Sixth tuff" to the GPTS.

    Right at the onset of the long-term Cenozoic cooling trend the dominant eccentricity-modulated precession cycles of ODP Site 1258 are interrupted by strong obliquity cycles for a period of ~800 kyr in the middle of magnetochron C22r. These distinct obliquity cycles at this low latitude site point to (1 a high-latitude driving mechanism on global climate variability from 50.1 to 49.4 Ma, and (2 seem to coincide with a significant drop in atmospheric CO2 concentration below a critical threshold between 2- and 3-times the pre-industrial level (PAL. The here newly identified orbital configuration of low eccentricity in combination with high obliquity amplitudes during this ~800-kyr period and the crossing of a critical pCO2 threshold may have led to the formation of the first ephemeral

  12. Vector-borne transmission of Trypanosoma cruzi among captive Neotropical primates in a Brazilian zoo. (United States)

    Minuzzi-Souza, Thaís Tâmara Castro; Nitz, Nadjar; Knox, Monique Britto; Reis, Filipe; Hagström, Luciana; Cuba, César A Cuba; Hecht, Mariana Machado; Gurgel-Gonçalves, Rodrigo


    Neotropical primates are important sylvatic hosts of Trypanosoma cruzi, the etiological agent of Chagas disease. Infection is often subclinical, but severe disease has been described in both free-ranging and captive primates. Panstrongylus megistus, a major T. cruzi vector, was found infesting a small-primate unit at Brasília zoo (ZooB), Brazil. ZooB lies close to a gallery-forest patch where T. cruzi circulates naturally. Here, we combine parasitological and molecular methods to investigate a focus of T. cruzi infection involving triatomine bugs and Neotropical primates at a zoo located in the Brazilian Savannah. We assessed T. cruzi infection in vectors using optical microscopy (n = 34) and nested PCR (n = 50). We used quantitative PCR (qPCR) to examine blood samples from 26 primates and necropsy samples from two primates that died during the study. We determined parasite lineages in five vectors and two primates by comparing glucose-6-phosphate isomerase (G6pi) gene sequences. Trypanosoma cruzi was found in 44 vectors and 17 primates (six genera and eight species); one Mico chrysoleucus and one Saguinus niger had high parasitaemias. Trypanosoma cruzi DNA was detected in three primates born to qPCR-negative mothers at ZooB and in the two dead specimens. One Callithrix geoffroyi became qPCR-positive over a two-year follow-up. All G6pi sequences matched T. cruzi lineage TcI. Our findings strongly suggest vector-borne T. cruzi transmission within a small-primate unit at ZooB - with vectors, and perhaps also parasites, presumably coming from nearby gallery forest. Periodic checks for vectors and parasites would help eliminate T. cruzi transmission foci in captive-animal facilities. This should be of special importance for captive-breeding programs involving endangered mammals, and would reduce the risk of accidental T. cruzi transmission to keepers and veterinarians.

  13. Liquidambar maomingensis sp. nov. (Altingiaceae) from the late Eocene of South China. (United States)

    Maslova, Natalia P; Kodrul, Tatiana M; Song, Yunsheng; Volkova, Lyudmila D; Jin, Jianhua


    • Phylogenetic analysis of DNA sequence data has changed our view on the evolution and systematics of plant taxa. Based on the phylogenetic analysis of several molecular markers, fruit anatomy, and pollen morphology, the genera Altingia and Semiliquidambar were formally transferred to the genus Liquidambar. The new species of Liquidambar from the Eocene of South China significantly extends our knowledge of the variability of the morphological characters of this genus in the geological past. Fossil leaves in conjunction with data on the associated reproductive structures allow us to make inferences about patterns in the evolutionary history of Liquidambar.• Fossil leaves and associated reproductive structures preserved as impressions were described and compared with the corresponding organs of extant and fossil relatives. The morphological variation of numerous leaves was examined by stereomicroscopy.• Liquidambar maomingensis sp. nov. is characterized by polymorphic leaves including both palmately lobed and unlobed leaves. This study presents the first observations of such dimorphism in the fossil record of Liquidambar leaves. Two distinct leaf groups are interpreted as sun and shade leaves.• The fossil leaves and associated infructescences from Maoming probably belong to the same plant. The occurrence of fossil leaves similar to those of extant species previously considered within Semiliquidambar and Liquidambar with the associated infructescences close to those of Altingia provide paleobotanical evidence that justifies combining the genera Liquidambar, Altingia, and Semiliquidambar into the single genus Liquidambar as recently proposed based on molecular markers. © 2015 Botanical Society of America, Inc.

  14. Sedimentology and paleoecology of an Eocene Oligocene alluvial lacustrine arid system, Southern Mexico (United States)

    Beraldi-Campesi, Hugo; Cevallos-Ferriz, Sergio R. S.; Centeno-García, Elena; Arenas-Abad, Concepción; Fernández, Luis Pedro


    A depositional model of the Eocene-Oligocene Coatzingo Formation in Tepexi de Rodríguez (Puebla, Mexico) is proposed, based on facies analysis of one of the best-preserved sections, the Axamilpa Section. The sedimentary evolution is interpreted as the retrogradation of an alluvial system, followed by the progressive expansion of an alkaline lake system, with deltaic, palustrine, and evaporitic environments. The analysis suggests a change towards more arid conditions with time. Fossils from this region, such as fossil tracks of artiodactyls, aquatic birds and cat-like mammals, suggest that these animals traversed the area, ostracods populated the lake waters, and plants grew on incipient soils and riparian environments many times throughout the history of the basin. The inferred habitat for some fossil plants coincides with the sedimentological interpretation of an arid to semiarid climate for that epoch. This combined sedimentological-paleontological study of the Axamilpa Section provides an environmental context in which fossils can be placed and brings into attention important biotic episodes, like bird and camelid migrations or the origin of endemic but extinct plants in this area.

  15. Palynostratigraphy and depositional environment of Vastan Lignite Mine (Early Eocene), Gujarat, western India (United States)

    Rao, M. R.; Sahni, Ashok; Rana, R. S.; Verma, Poonam


    Early Eocene sedimentary successions of south Asia, are marked by the development of extensive fossil-bearing, lignite-rich sediments prior to the collision of India with Asia and provide data on contemporary equatorial faunal and vegetational assemblages. One such productive locality in western India is the Vastan Lignite Mine representing approximately a 54-52 Ma sequence dated by the presence of benthic zone marker species, Nummulites burdigalensis burdigalensis. The present study on Vastan Lignite Mine succession is based on the spore-pollen and dinoflagellate cyst assemblages and documents contemporary vegetational changes. 86 genera and 105 species belonging to algal remains (including dinoflagellate cysts), fungal remains, pteridophytic spores and angiospermous pollen grains have been recorded. On the basis of first appearance, acme and decline of palynotaxa, three cenozones have been recognized and broadly reflect changing palaeodepositional environments. These are in ascending stratigraphic order (i) Proxapertites Spp. Cenozone, (ii) Operculodinium centrocarpum Cenozone and (iii) Spinizonocolpites Spp. Cenozone. The basal sequence is lagoonal, palm-dominated and overlain by more open marine conditions with dinoflagellate cysts and at the top, mangrove elements are dominant. The succession has also provided a unique record of fish, lizards, snakes, and mammals.

  16. Eustatic control on synchronous stratigraphic development: cretaceous and eocene coastal basins along an active margin (United States)

    May, Jeffrey A.; Yeo, Ross K.; Warme, John E.


    Field studies document an apparent eustatic control on facies patterns along a tectonically active margin. In the San Diego Embayment and northern Baja California, progradational-retrogradational shoreline sequences characterize Late Cretaceous and Eocene forearc stratigraphy. Extensive benthonic foraminifera and nannoplankton data provide control on the age and distribution of facies changes along these depositionally compact, bathymetrically steep-gradient margins. The complete stratigraphic package is arranged into three scales and patterns of depositional sequences. Timing and geometry of the two largest sequences provide relative sea-level curves that correlate exceptionally well with worldwide sea-level curves. The major depositional cycle is asymmetric, hundreds of meters thick, characterized by a thin basal retrogradational sequence overlain by a thick progradational sequence; each cycle correlates to a coastal-onlap "supercycle". Smaller scale stratigraphic rhythms, controlled by global "cycles" and "paracycles", compose depositional cycles. Local depostional pulses overprint these two larger order sequences of sedimentation. Coeval cycles and depositional rhythms in isolated coastal basins from Oregon to Baja California further indicate a primary eustatic control on sedimentation. Field-based facies analysis thus supports the use of the "Vail curve" or other coastal-onlap and global sea-level curves as a predictive tool in basin analysis.

  17. Late Eocene siliceous sponge fauna of southern Australia: reconstruction based on loose spicules record. (United States)

    Łukowiak, Magdalena


    An abundant and diversified assemblage of siliceous loose sponge spicules has been identified in the Late Eocene deposits cropping out along the southern coasts of Australia. Based on the comparison of the obtained spicules with those of living sponges, representatives of at least 43 species within 33 genera, 26 families, and 9 orders of "soft" Demospongiae and Homoscleromorpha have been identified in the assemblage. Within the studied sediments, the spicules representing demosponge orders Poecilosclerida, Hadromerida, and Astrophorida were the most diverse. The rest of the five demosponge orders (Halichondrida, Agelasida, Haplosclerida, Spirophorida, and Chondrosida) are represented by single families. Also, a single family Plakinidae within the class Homoscleromorpha that includes two genera was present. The diversity of spicules is similar in all studied samples and areas, even distant geographically, and there are only minor differences between the sections. That indicates a homogenous character of this rich siliceous sponge assemblage. Most of the studied sponge spicules have Recent equivalents among present-day siliceous spicules. However, the fossil ones are bigger which is most likely due to different environmental conditions. Among the recognized sponge species, at least eleven (Agelas cf. axifera, Agelas cf. wiedenmayeri, Penares sclerobesa, Histodermella australis, Trikentrion flabelliforme, Cliona cf. mucronata, Tethya cf. omanensis, Terpios sp., Placinolopha cf. sarai, Dotona pulchella, and Sigmosceptrella quadrilobata) are noted for the first time in the fossil record.

  18. Enrichment of dissolved silica in the deep equatorial Pacific during the Eocene-Oligocene (United States)

    Fontorbe, Guillaume; Frings, Patrick J.; De La Rocha, Christina L.; Hendry, Katharine R.; Carstensen, Jacob; Conley, Daniel J.


    Silicon isotope ratios (expressed as δ30Si) in marine microfossils can provide insights into silica cycling over geologic time. Here we used δ30Si of sponge spicules and radiolarian tests from the Paleogene Equatorial Transect (Ocean Drilling Program Leg 199) spanning the Eocene and Oligocene ( 50-23 Ma) to reconstruct dissolved silica (DSi) concentrations in deep waters and to examine upper ocean δ30Si. The δ30Si values range from -3.16 to +0.18‰ and from -0.07 to +1.42‰ for the sponge and radiolarian records, respectively. Both records show a transition toward lower δ30Si values around 37 Ma. The shift in radiolarian δ30Si is interpreted as a consequence of changes in the δ30Si of source DSi to the region. The decrease in sponge δ30Si is interpreted as a transition from low DSi concentrations to higher DSi concentrations, most likely related to the shift toward a solely Southern Ocean source of deep water in the Pacific during the Paleogene that has been suggested by results from paleoceanographic tracers such as neodymium and carbon isotopes. Sponge δ30Si provides relatively direct information about the nutrient content of deep water and is a useful complement to other tracers of deep water circulation in the oceans of the past.

  19. Hemoglobin-derived porphyrins preserved in a Middle Eocene blood-engorged mosquito (United States)

    Greenwalt, Dale E.; Goreva, Yulia S.; Siljeström, Sandra M.; Rose, Tim; Harbach, Ralph E.


    Although hematophagy is found in ∼14,000 species of extant insects, the fossil record of blood-feeding insects is extremely poor and largely confined to specimens identified as hematophagic based on their taxonomic affinities with extant hematophagic insects; direct evidence of hematophagy is limited to four insect fossils in which trypanosomes and the malarial protozoan Plasmodium have been found. Here, we describe a blood-engorged mosquito from the Middle Eocene Kishenehn Formation in Montana. This unique specimen provided the opportunity to ask whether or not hemoglobin, or biomolecules derived from hemoglobin, were preserved in the fossilized blood meal. The abdomen of the fossil mosquito was shown to contain very high levels of iron, and mass spectrometry data provided a convincing identification of porphyrin molecules derived from the oxygen-carrying heme moiety of hemoglobin. These data confirm the existence of taphonomic conditions conducive to the preservation of biomolecules through deep time and support previous reports of the existence of heme-derived porphyrins in terrestrial fossils. PMID:24127577

  20. Sea-level and salinity fluctuations during the Paleocene-Eocene thermal maximum in Arctic Spitsbergen (United States)

    Harding, Ian C.; Charles, Adam J.; Marshall, John E. A.; Pälike, Heiko; Roberts, Andrew P.; Wilson, Paul A.; Jarvis, Edward; Thorne, Robert; Morris, Emily; Moremon, Rebecca; Pearce, Richard B.; Akbari, Shir


    Palaeoenvironmental manifestations of the Paleocene-Eocene thermal maximum (PETM; ~ 56 Ma) are relatively well documented in low- to mid-latitude settings and at high southern latitudes, but no documented high northern latitude sites record the entire hyperthermal event. We present high-resolution multi-proxy records from a PETM succession on Spitsbergen in the high Arctic (palaeolatitude ~ 75 °N). By comparing our results with those from Integrated Ocean Drilling Program Site 302-4A, we document regional palaeoenvironmental variations in the expression of the PETM, with evidence for major differences in basin-margin vegetation and water column oxygen depletion. Sedimentological, palynological and geochemical data demonstrate a pre-PETM sea level rise in Spitsbergen before the - 4‰ δ 13C TOC excursion, which culminated in maximum flooding during the peak of the event. The appearance of the dinoflagellate cyst Apectodinium before the onset of the carbon isotope excursion (CIE) corroborates that environmental change in the Arctic had begun prior to the CIE. Sedimentological and palynological evidence indicate that elevated terrestrial runoff resulted in water column stratification, providing further evidence for an intensification of the hydrological cycle during the PETM.

  1. What caused the long duration of the Paleocene-Eocene Thermal Maximum? (United States)

    Zeebe, R. E.


    Paleorecords show that the Paleocene-Eocene Thermal Maximum (PETM, 56 Ma) was associated with a large carbon isotope excursion and global warming >5 K. Surprisingly, the records indicate little if any decline in, for instance, stable carbon isotope values after 50 kyr. Similar durations of the PETM main phase can be inferred from oxygen isotope records (indicating temperature) and surface ocean carbonate chemistry proxies. The inferred main phase duration of > 50 kyr is also independent of the age model applied. One age model is based on orbital cycle stratigraphy, the other on extraterrestrial 3He concentrations. Despite differences in the age models, they agree that the duration of the PETM main phase lasted for at least 50 kyr, a duration that is also consistent with observations from the most expanded terrestrial sequences. Conventional carbon-cycle/climate models forced with an initial carbon input pulse over ~10 kyr fail to reproduce the long duration of the PETM without invoking additional, slow carbon release over more than 50~kyr (so-called bleeding). However, a potential carbon source for the bleeding, as well as its release mechanism have hitherto remained elusive. In this presentation, I will suggest a plausible mechanism for the long duration of the PETM based on first-principle calculations. If the mechanism is also applicable to the near future, the magnitude and duration of future warming could substantially exceed current projections.

  2. Deep-sea redox across the Paleocene-Eocene thermal maximum (United States)

    Pälike, Cecily; Delaney, Margaret L.; Zachos, James C.


    amounts of 13C-depleted carbon were released to the oceans and atmosphere during a period of abrupt global warming at the Paleocene-Eocene thermal maximum (PETM) (˜55 Ma). Investigations of qualitative sedimentologic and paleontologic redox proxies such as bioturbation and benthic assemblages from pelagic and hemipelagic sections suggest transient reductions in bottom water oxygen during this interval, possibly on a global scale. Here, we present bulk sediment manganese (Mn) and uranium (U) enrichment factors (EF) in Atlantic and Pacific deep-sea cores to constrain relative paleoredox changes across the PETM. Mn EF range from 1 to 9 in Atlantic sites, 1 to 35 in Southern Ocean sites, and are at crustal averages (EF = 1) in Pacific sites. U EF range from 1 to 5 in Atlantic sites, 1 to 90 in Southern Ocean sites, and are at crustal averages in Pacific sites. Our results indicate suboxic conditions prior to, during, and in the recovery from the PETM at intermediate depth sites in the Atlantic and Southern Ocean while the Pacific sites remained relatively oxygenated. The difference in oxygenation between the Atlantic and Pacific sites leads us to suggest the source for isotopically light carbon release during the PETM was in the Atlantic.

  3. Environmental changes during the Paleocene–Eocene Thermal Maximum in Spitsbergen as reflected by benthic foraminifera

    Directory of Open Access Journals (Sweden)

    Jenö Nagy


    Full Text Available The study deals with environmental changes during the Paleocene–Eocene Thermal Maximum (PETM and its background conditions in Spitsbergen through analysis of benthic foraminiferal assemblages (FA in a section drilled in the Paleogene Central Basin. The impact of this extreme global warming occurs here in prodelta shelf mudstones composing the lower part of the Gilsonryggen Member (Frysjaodden Formation. The start of the PETM perturbation is marked by a faunal turnover, in which the medium-diversity circumpolar Reticulophragmium assemblage was replaced by a low-diversity Trochammina fauna. During the hyperthermal period, benthic foraminiferal diversity decreased severely, while the dominance of small-sized taxa with epifaunal morphology strongly increased. This low-diversity fauna occurs in sediments with a reduced thorium/uranium ratio (proxy for oxygenation and kaolinite enrichment (proxy for high humidity. The faunal changes were thus caused by the combined effects of hypoxic and hyposaline conditions in a stratified water column, due to extreme warming with its accompanying intensified hydrologic cycle. The PETM acme coincides with the maximum flooding surface (MFS of the Gilsonryggen depositional sequence, composed of the Gilsonryggen Member and the overlying Battfjellet and Aspelintoppen formations. The transgressive phase of the sequence was initiated by local tectonics, while the eustatic sea-level rise of the PETM was superimposed on this transgression.To access the supplementary material for this article, please see supplementary files under Article Tools online.

  4. Value of information analysis for groundwater quality monitoring network design Case study: Eocene Aquifer, Palestine (United States)

    Khader, A.; McKee, M.


    Value of information (VOI) analysis evaluates the benefit of collecting additional information to reduce or eliminate uncertainty in a specific decision-making context. It makes explicit any expected potential losses from errors in decision making due to uncertainty and identifies the “best” information collection strategy as one that leads to the greatest expected net benefit to the decision-maker. This study investigates the willingness to pay for groundwater quality monitoring in the Eocene Aquifer, Palestine, which is an unconfined aquifer located in the northern part of the West Bank. The aquifer is being used by 128,000 Palestinians to fulfill domestic and agricultural demands. The study takes into account the consequences of pollution and the options the decision maker might face. Since nitrate is the major pollutant in the aquifer, the consequences of nitrate pollution were analyzed, which mainly consists of the possibility of methemoglobinemia (blue baby syndrome). In this case, the value of monitoring was compared to the costs of treating for methemoglobinemia or the costs of other options like water treatment, using bottled water or importing water from outside the aquifer. And finally, an optimal monitoring network that takes into account the uncertainties in recharge (climate), aquifer properties (hydraulic conductivity), pollutant chemical reaction (decay factor), and the value of monitoring is designed by utilizing a sparse Bayesian modeling algorithm called a relevance vector machine.

  5. Characterization of organics consistent with β-chitin preserved in the Late Eocene cuttlefish Mississaepia mississippiensis.

    Directory of Open Access Journals (Sweden)

    Patricia G Weaver

    Full Text Available BACKGROUND: Preservation of original organic components in fossils across geological time is controversial, but the potential such molecules have for elucidating evolutionary processes and phylogenetic relationships is invaluable. Chitin is one such molecule. Ancient chitin has been recovered from both terrestrial and marine arthropods, but prior to this study had not been recovered from fossil marine mollusks. METHODOLOGY/PRINCIPAL FINDINGS: Organics consistent with β-chitin are recovered in cuttlebones of Mississaepia mississippiensis from the Late Eocene (34.36 million years ago marine clays of Hinds County, Mississippi, USA. These organics were determined and characterized through comparisons with extant taxa using Scanning Electron Microscopy/Energy Dispersive Spectrometry (SEM/EDS, Field Emission Scanning Electron Microscopy (Hyperprobe, Fourier Transmission Infrared Spectroscopy (FTIR and Immunohistochemistry (IHC. CONCLUSIONS/SIGNIFICANCE: Our study presents the first evidence for organics consistent with chitin from an ancient marine mollusk and discusses how these organics have been degraded over time. As mechanisms for their preservation, we propose that the inorganic/organic lamination of the cuttlebone, combined with a suboxic depositional environment with available free Fe(2+ ions, inhibited microbial or enzymatic degradation.

  6. Productivity feedback did not terminate the Paleocene-Eocene Thermal Maximum (PETM

    Directory of Open Access Journals (Sweden)

    A. Torfstein


    Full Text Available The Paleocene-Eocene Thermal Maximum (PETM occurred approximately 55 million years ago, and is one of the most dramatic abrupt global warming events in the geological record. This warming was triggered by the sudden release of thousands of gigatons of carbon into the atmosphere and is widely perceived to be the best analogue for current anthropogenic climate change. Yet, the mechanism of recovery from this event remains controversial. A massive increase in the intensity of the marine biological pump ("productivity feedback" has been suggested to cause a drawdown of atmospheric CO2 and subsequent carbon sequestration in the ocean. A re-evaluation of the "productivity feedback hypothesis", based on biogenic barium mass accumulation rates (Ba-MARs for a site in the Southern Ocean, finds that any increase in export production lagged the initial carbon release by at least ~70 000 years. This implies that export production did not facilitate rapid removal of excess carbon from the atmosphere. Thus, the most likely mechanism for carbon removal appears to be silicate weathering, which occurred at much slower rates than previously assumed.

  7. Palaeocommunities, diversity and sea-level change from middle Eocene shell beds of the Paris Basin (United States)

    Dominici, Stefano; Zuschin, Martin


    The middle Eocene, a time of global transition from greenhouse to icehouse climate, was approached through high-resolution stratigraphy at a few classic localities of the Paris Basin. Quantitative data on the distribution of molluscan species abundance, collected at 12 different shell beds representative of the middle Lutetian and the lower Bartonian, formed the basis for a palaeoecological study. The succession can be subdivided into a hierarchy of depositional sequences, interpreted as the product of relative sea-level change. Abundance distributions are better correlated with 5th-order depositional sequences than geographic locality, suggesting that sea-level played an important role in the distribution of palaeocommunities. Rarefied diversities were measured and compared with analogous data from modern tropical and warm-temperate intertidal and subtidal communities. The palaeoecological analysis shows that sea-level variation is responsible for a major change in the upper part of the middle Lutetian, leading from high-diversity subtidal to low-diversity intertidal and shallow subtidal palaeocommunities. The study did not confirm that the stage-level drop in species richness documented in this basin is related to the global climatic deterioration. Instead, the global climatic signal might be obscured in the Paris Basin by facies control.

  8. Patterns of gut bacterial colonization in three primate species. (United States)

    McKenney, Erin A; Rodrigo, Allen; Yoder, Anne D


    Host fitness is impacted by trillions of bacteria in the gastrointestinal tract that facilitate development and are inextricably tied to life history. During development, microbial colonization primes the gut metabolism and physiology, thereby setting the stage for adult nutrition and health. However, the ecological rules governing microbial succession are poorly understood. In this study, we examined the relationship between host lineage, captive diet, and life stage and gut microbiota characteristics in three primate species (infraorder, Lemuriformes). Fecal samples were collected from captive lemur mothers and their infants, from birth to weaning. Microbial DNA was extracted and the v4 region of 16S rDNA was sequenced on the Illumina platform using protocols from the Earth Microbiome Project. Here, we show that colonization proceeds along different successional trajectories in developing infants from species with differing dietary regimes and ecological profiles: frugivorous (fruit-eating) Varecia variegata, generalist Lemur catta, and folivorous (leaf-eating) Propithecus coquereli. Our analyses reveal community membership and succession patterns consistent with previous studies of human infants, suggesting that lemurs may serve as a useful model of microbial ecology in the primate gut. Each lemur species exhibits distinct species-specific bacterial diversity signatures correlating to life stages and life history traits, implying that gut microbial community assembly primes developing infants at species-specific rates for their respective adult feeding strategies.

  9. Multidisciplinary studies of wildlife trade in primates: Challenges and priorities. (United States)

    Blair, Mary E; Le, Minh D; Sterling, Eleanor J


    Wildlife trade is increasingly recognized as an unsustainable threat to primate populations and informing its management is a growing focus and application of primatological research. However, management policies based on ecological research alone cannot address complex socioeconomic or cultural contexts as drivers of wildlife trade. Multidisciplinary research is required to understand trade complexity and identify sustainable management strategies. Here, we define multidisciplinary research as research that combines more than one academic discipline, and highlight how the articles in this issue combine methods and approaches to fill key gaps and offer a more comprehensive understanding of underlying drivers of wildlife trade including consumer demand, enforcement patterns, source population status, and accessibility of targeted species. These articles also focus on how these drivers interact at different scales, how trade patterns relate to ethics, and the potential effectiveness of different policy interventions in reducing wildlife trade. We propose priorities for future research on primate trade including expanding from multidisciplinary to interdisciplinary research questions and approaches co-created by research teams that integrate across different disciplines such as cultural anthropology, ecology, economics, and public policy. We also discuss challenges that limit the integration of information across disciplines to meet these priorities. © 2017 Wiley Periodicals, Inc.

  10. Tempo and mode of climatic niche evolution in Primates. (United States)

    Duran, Andressa; Pie, Marcio R


    Climatic niches have increasingly become a nexus in our understanding of a variety of ecological and evolutionary phenomena, from species distributions to latitudinal diversity gradients. Despite the increasing availability of comprehensive datasets on species ranges, phylogenetic histories, and georeferenced environmental conditions, studies on the evolution of climate niches have only begun to understand how niches evolve over evolutionary timescales. Here, using primates as a model system, we integrate recently developed phylogenetic comparative methods, species distribution patterns, and climatic data to explore primate climatic niche evolution, both among clades and over time. In general, we found that simple, constant-rate models provide a poor representation of how climatic niches evolve. For instance, there have been shifts in the rate of climatic niche evolution in several independent clades, particularly in response to the increasingly cooler climates of the past 10 My. Interestingly, rate accelerations greatly outnumbered rate decelerations. These results highlight the importance of considering more realistic evolutionary models that allow for the detection of heterogeneity in the tempo and mode of climatic niche evolution, as well as to infer possible constraining factors for species distributions in geographical space. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

  11. Functional asymmetry of emotions in primates: new findings in chimpanzees. (United States)

    Fernández-Carriba, Samuel; Loeches, Angela; Morcillo, Ana; Hopkins, William D

    In the past 15 years, there have been a number of studies conducted on asymmetries in the perception and production of facial expressions in human and non-human primates as a means of inferring hemispheric specialization for emotions. We review these studies to assess continuity and discontinuity between species in these emotional processes. We further present new data on asymmetries in the production of facial expressions in a sample of captive chimpanzees. Objective measures (hemimouth length and area) and subjective measures (human judgement's of chimeric stimuli) indicate that chimpanzees' facial expressions are asymmetric, with a greater involvement of the left side of the face (right hemisphere) in the production of emotional responses. Left hemimouth was bigger than the right in the facial expressions of pant-hooting, play, and silent bared-teeth (p bared-teeth, and scream face (p bared-teeth categories (p < 0.01). Thus, chimpanzees, like humans and some other non-human primates, show a right hemisphere specialization for facial expression of emotions, which suggests that this functional asymmetry is homologous in all these species.

  12. Female and male life tables for seven wild primate species (United States)

    Bronikowski, Anne M.; Cords, Marina; Alberts, Susan C.; Altmann, Jeanne; Brockman, Diane K.; Fedigan, Linda M.; Pusey, Anne; Stoinski, Tara; Strier, Karen B.; Morris, William F.


    We provide male and female census count data, age-specific survivorship, and female age-specific fertility estimates for populations of seven wild primates that have been continuously monitored for at least 29 years: sifaka (Propithecus verreauxi) in Madagascar; muriqui (Brachyteles hypoxanthus) in Brazil; capuchin (Cebus capucinus) in Costa Rica; baboon (Papio cynocephalus) and blue monkey (Cercopithecus mitis) in Kenya; chimpanzee (Pan troglodytes) in Tanzania; and gorilla (Gorilla beringei) in Rwanda. Using one-year age-class intervals, we computed point estimates of age-specific survival for both sexes. In all species, our survival estimates for the dispersing sex are affected by heavy censoring. We also calculated reproductive value, life expectancy, and mortality hazards for females. We used bootstrapping to place confidence intervals on life-table summary metrics (R0, the net reproductive rate; λ, the population growth rate; and G, the generation time). These data have high potential for reuse; they derive from continuous population monitoring of long-lived organisms and will be invaluable for addressing questions about comparative demography, primate conservation and human evolution. PMID:26928014

  13. The Evolution of Trypanosomes Infecting Humans and Primates

    Directory of Open Access Journals (Sweden)

    Stevens Jamie


    Full Text Available Based on phylogenetic analysis of 18S rRNA sequences and clade taxon composition, this paper adopts a biogeographical approach to understanding the evolutionary relationships of the human and primate infective trypanosomes, Trypanosoma cruzi, T. brucei, T. rangeli and T. cyclops. Results indicate that these parasites have divergent origins and fundamentally different patterns of evolution. T. cruzi is placed in a clade with T. rangeli and trypanosomes specific to bats and a kangaroo. The predominantly South American and Australian origins of parasites within this clade suggest an ancient southern super-continent origin for ancestral T. cruzi, possibly in marsupials. T. brucei clusters exclusively with mammalian, salivarian trypanosomes of African origin, suggesting an evolutionary history confined to Africa, while T. cyclops, from an Asian primate appears to have evolved separately and is placed in a clade with T. (Megatrypanum species. Relating clade taxon composition to palaeogeographic evidence, the divergence of T. brucei and T. cruzi can be dated to the mid-Cretaceous, around 100 million years before present, following the separation of Africa, South America and Euramerica. Such an estimate of divergence time is considerably more recent than those of most previous studies based on molecular clock methods. Perhaps significantly, Salivarian trypanosomes appear, from these data, to be evolving several times faster than Schizotrypanum species, a factor which may have contributed to previous anomalous estimates of divergence times.

  14. Primate ABO Gene is under Weak Positive Selection

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    Eliane Santos EVANOVICH


    Full Text Available ABO locus presents three main alleles: A, B and O. A and B encode glycosyltransferases that catalyze the addiction of an N-GalNac and D-galactose to a precursor substance (H substance, producing A and B antigens, while the O allele does not produce a functional protein. The presence of A and B antigens have been associated to resistance against infectious agents which could use them as attachment factors increasing the virulence of some parasitic agents. As these antigens are not restrict to humans, analyses them in others species, for instance non-human primates, may be crucial to understand the relationship between pathogens and ABO phenotypes. Despite of the relevance of this issue, in the last decade few studies have addressed, mainly in New World Monkeys (NWM, natural reservoir of tropical diseases in Amazon Region. In order to understand the evolution of the ABO system in the primates, it has been obtained the partial sequence of the most important exon of ABO gene (exon 7, in platyrrhini families: Atelidae, Pithecidae and Cebidae. Then, it has been compared the sequences obtained those present in the literature, and measured the selective pressure. The present results shown that residues 266 and 268 are also crucial to distinguish A and B phenotypes in the platyrrhines, such as in catarrhines, and the 266 codon is under positive selection, although the most site codons are under action of purifying selection.

  15. Cognitive consilience: Primate non-primary neuroanatomical circuits underlying cognition

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    Soren Van Hout Solari


    Full Text Available Interactions between the cerebral cortex, thalamus, and basal ganglia form the basis ofcognitive information processing in the mammalian brain. Understanding the principles ofneuroanatomical organization in these structures is critical to understanding the functions theyperform and ultimately how the human brain works. We have manually distilled and synthesizedhundreds of primate neuroanatomy facts into a single interactive visualization. The resultingpicture represents the fundamental neuroanatomical blueprint upon which cognitive functionsmust be implemented. Within this framework we hypothesize and detail 7 functional circuitscorresponding to psychological perspectives on the brain: consolidated long-term declarativememory, short-term declarative memory, working memory/information processing, behavioralmemory selection, behavioral memory output, cognitive control, and cortical information flow regulation. Each circuit is described in terms of distinguishable neuronal groups including thecerebral isocortex (9 pyramidal neuronal groups, parahippocampal gyrus and hippocampus,thalamus (4 neuronal groups, basal ganglia (7 neuronal groups, metencephalon, basal forebrainand other subcortical nuclei. We focus on neuroanatomy related to primate non-primary corticalsystems to elucidate the basis underlying the distinct homotypical cognitive architecture. To dis-play the breadth of this review, we introduce a novel method of integrating and presenting datain multiple independent visualizations: an interactive website (www.cognitiveconsilience.comand standalone iPhone and iPad applications. With these tools we present a unique, annotatedview of neuroanatomical consilience (integration of knowledge.

  16. Evolution of the central sulcus morphology in primates. (United States)

    Hopkins, William D; Meguerditchian, Adrien; Coulon, Olivier; Bogart, Stephanie; Mangin, Jean-François; Sherwood, Chet C; Grabowski, Mark W; Bennett, Allyson J; Pierre, Peter J; Fears, Scott; Woods, Roger; Hof, Patrick R; Vauclair, Jacques


    The central sulcus (CS) divides the pre- and postcentral gyri along the dorsal-ventral plane of which all motor and sensory functions are topographically organized. The motor-hand area of the precentral gyrus or KNOB has been described as the anatomical substrate of the hand in humans. Given the importance of the hand in primate evolution, here we examine the evolution of the motor-hand area by comparing the relative size and pattern of cortical folding of the CS surface area from magnetic resonance images in 131 primates, including Old World monkeys, apes and humans. We found that humans and great apes have a well-formed motor-hand area that can be seen in the variation in depth of the CS along the dorsal-ventral plane. We further found that great apes have relatively large CS surface areas compared to Old World monkeys. However, relative to great apes, humans have a small motor-hand area in terms of both adjusted and absolute surface areas. © 2014 S. Karger AG, Basel.

  17. Context-dependent incremental timing cells in the primate hippocampus. (United States)

    Sakon, John J; Naya, Yuji; Wirth, Sylvia; Suzuki, Wendy A


    We examined timing-related signals in primate hippocampal cells as animals performed an object-place (OP) associative learning task. We found hippocampal cells with firing rates that incrementally increased or decreased across the memory delay interval of the task, which we refer to as incremental timing cells (ITCs). Three distinct categories of ITCs were identified. Agnostic ITCs did not distinguish between different trial types. The remaining two categories of cells signaled time and trial context together: One category of cells tracked time depending on the behavioral action required for a correct response (i.e., early vs. late release), whereas the other category of cells tracked time only for those trials cued with a specific OP combination. The context-sensitive ITCs were observed more often during sessions where behavioral learning was observed and exhibited reduced incremental firing on incorrect trials. Thus, single primate hippocampal cells signal information about trial timing, which can be linked with trial type/context in a learning-dependent manner.

  18. Corvids Outperform Pigeons and Primates in Learning a Basic Concept. (United States)

    Wright, Anthony A; Magnotti, John F; Katz, Jeffrey S; Leonard, Kevin; Vernouillet, Alizée; Kelly, Debbie M


    Corvids (birds of the family Corvidae) display intelligent behavior previously ascribed only to primates, but such feats are not directly comparable across species. To make direct species comparisons, we used a same/different task in the laboratory to assess abstract-concept learning in black-billed magpies ( Pica hudsonia). Concept learning was tested with novel pictures after training. Concept learning improved with training-set size, and test accuracy eventually matched training accuracy-full concept learning-with a 128-picture set; this magpie performance was equivalent to that of Clark's nutcrackers (a species of corvid) and monkeys (rhesus, capuchin) and better than that of pigeons. Even with an initial 8-item picture set, both corvid species showed partial concept learning, outperforming both monkeys and pigeons. Similar corvid performance refutes the hypothesis that nutcrackers' prolific cache-location memory accounts for their superior concept learning, because magpies rely less on caching. That corvids with "primitive" neural architectures evolved to equal primates in full concept learning and even to outperform them on the initial 8-item picture test is a testament to the shared (convergent) survival importance of abstract-concept learning.

  19. Patterns of gut bacterial colonization in three primate species.

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    Erin A McKenney

    Full Text Available Host fitness is impacted by trillions of bacteria in the gastrointestinal tract that facilitate development and are inextricably tied to life history. During development, microbial colonization primes the gut metabolism and physiology, thereby setting the stage for adult nutrition and health. However, the ecological rules governing microbial succession are poorly understood. In this study, we examined the relationship between host lineage, captive diet, and life stage and gut microbiota characteristics in three primate species (infraorder, Lemuriformes. Fecal samples were collected from captive lemur mothers and their infants, from birth to weaning. Microbial DNA was extracted and the v4 region of 16S rDNA was sequenced on the Illumina platform using protocols from the Earth Microbiome Project. Here, we show that colonization proceeds along different successional trajectories in developing infants from species with differing dietary regimes and ecological profiles: frugivorous (fruit-eating Varecia variegata, generalist Lemur catta, and folivorous (leaf-eating Propithecus coquereli. Our analyses reveal community membership and succession patterns consistent with previous studies of human infants, suggesting that lemurs may serve as a useful model of microbial ecology in the primate gut. Each lemur species exhibits distinct species-specific bacterial diversity signatures correlating to life stages and life history traits, implying that gut microbial community assembly primes developing infants at species-specific rates for their respective adult feeding strategies.

  20. Mandibular biomechanics and temporomandibular joint function in primates. (United States)

    Smith, R J


    There is disagreement as to whether the mandibular condyles are stress-bearing or stress-free during mastication. In support of alternative models, analogies have been drawn with Class III levers, links, and couple systems. Physiological data are reviewed which indicate that maximum masticatory forces are generated when maxillary and mandibular teeth are in contact, and that this phase lasts for over 100 msec during many chewing strokes. During this period, the mandible can be modeled as a beam with multiple supports. Equations of simple beam theory suggest that large condylar reaction forces are present during mastication. With unilateral molar biting in man, the total condylar reaction force may be over 75% of the bite force. Analysis of a frontal projection demonstrates that up to 80% of the total condylar reaction force is borne by the contralateral (balancing side) condyle during unilateral molar biting. A comparison of human, chimpanzee (P. troglodytes), spider monkey (A. belzebuth), and macaque (Macaca sp.) morphology indicates that the frugivorous chimpanzee and spider monkey have a relatively lower condylar reaction force than the omnivorous macaque or man during molar biting. The percentage reaction force during incisal biting is lower in man than in the other primates, and lower in the frugivorous primates than in the macaque.

  1. Ecological and evolutionary response of Tethyan planktonic foraminifera to the Middle Eocene Climatic Optimum (Alano di Piave section, NE Italy) (United States)

    Luciani, V.; Agnini, C.; Fornaciari, E.; Giusberti, L.; Rio, D.; Spofforth, D. J. A.; Pälike, H.


    The transient (ca. 500 kyr) climatic warming event at ca. 40 Ma, known as Middle Eocene Climatic Optimum (MECO), significantly interrupted the overall cooling trend of the Middle Eocene. Originally documented in several deep sea sites at the Southern Ocean (Bohaty and Zachos, 2003), now it appears to be recorded worldwide by pronounced changes of the ^13C and ^18O values and coeval oscillations in global CCD (Tripati et al, 2005). Information on the planktonic foraminiferal response to this event is so far lacking. Here we present a detailed planktonic foraminiferal analysis of the MECO interval from a marginal basin of the central-western Tethys (Alano di Piave section, northeastern Italy). The expanded and continuous Alano section provides an excellent record of this event and offers an unique opportunity to better understand the role of climate upon calcareous plankton evolution. The initiation of the MECO occurs within magnetochron C18r at ca. 40.5 Ma with minimum ^18O and ^13C values achieved at the base of C18n.2n ca. 40.13 Ma, which are interpreted to represent peak warming conditions. Two sapropel-like, organic-rich intervals coincide with the major change in ^13C record at Alano (Agnini et al., 2007a; Spofforth et al., 2008). The MECO event correlates the E12 (P13) and lower E3 (P14) planktonic foraminiferal zones. The high-resolution quantitative planktonic foraminiferal analysis performed on both >38 m and >63 m fraction reveals pronounced and complex changes indicating a strong environmental perturbation that parallels the variations of the stable isotope curves. These changes are primarily represented by the marked increase in abundance of the eutrophic subbotinids and of the small, low-oxygen tolerant Streptochilus, Chiloguembelina and Pseudohastigerina, by the consistent and significant entrance of the eutrophic opportunist triserial Jenkynsina and of Pseudoglobigerinella bolivariana, typical species of high-productivity, upwelling areas. The

  2. Lithospheric convective removal related post-collisional middle Eocene magmatism along the Izmir-Ankara-Erzincan suture zone (NE Turkey). (United States)

    Göçmengil, Gönenç; Karacık, Zekiye; Genç, Ş. Can


    Obliteration of the Mesozoic Neo-Tethyan Ocean and succeeding collision of the micro plates along the northern part of Turkey lead the development of the İzmir-Ankara-Erzincan suture zone (IAESZ). The suturing and collision stages terminate with the amalgamation of the three different crustal blocks (Pontides, Central Anatolian Crystalline Complex and Anatolide-Tauride Block) in the Paleocene-Early Eocene period. After the collisional stage; a new phase of extension and magmatism concomitantly developed at the both sides and as well as along the IAESZ during the Middle Eocene period. However, the origin, mechanism and driving force of the post-collisional magmatism is still enigmatic. To understand and better constrain the syn-to post collisional evolutionary stages, we have carried out volcano-stratigraphy and geochemistry based study on the middle Eocene magmatic associations along a transect ( 100 km) from Pontides to the Central Anatolian Crystalline Complex (CACC) at the NE part of the Turkey. Middle Eocene magmatic activity in the region has been represented by calc-alkaline, alkaline, shoshonitic volcanic and granitic rocks together with scarce gabbroic intrusions. We particularly focused on middle Eocene volcano-sedimentary successions (MEVSS) to constrain the tectono-magmatic evolution of the abovementioned transect. The volcano-sedimentary succsessions are coevally developed and cover the crustal blocks (Pontides and CACC) and the IAESZ with a region wide unconformity. We have differentiated three lava series (V1-V2-V3) and their sub-groups (V1a-V1b; V2a-V2b) in MEVSS. Generally, all lava series have middle-K to shoshonitic composition with distinct subduction characteristics. V1 series is marked by presence of hydrous phenocrysts such as amphibole+biotite. V1a sub-group constitute the first volcanic product and characterized by the high Mg# (42-69); alkaline basaltic andesite, and hawaiites. V1b sub-group is represented by calc-alkaline, low Mg# (24

  3. Early-middle Eocene transition in calcareous nannofossil assemblages at IODP Site U1410 (Southeast Newfoundland Ridge, NW Atlantic) (United States)

    Cappelli, Carlotta; Agnini, Claudia; Yamamoto, Yuhji


    The early-middle Eocene interval documents the shift from the warmest greenhouse conditions occurred during the Early Eocene Climatic Optimum (EECO, 52-50 Ma) to the beginning of the cooling phase which led to the Oligocene icehouse regime. This important transition is well expressed as a reversal in the global oxygen and carbonate isotope trends (Zachos et al., 2001). Moreover, this interval was a time of remarkable transformation in the marine biosphere. Communities of calcareous nannoplankton, marine calcifying algae at the base of the oceans food chain, experienced transient and permanent profound changes. Calcareous nannofossil are regarded as remarkable tools both in biostratigraphy and paleoecology, with several taxa that show different responses to changes in physical parameters of surface waters. Here, we aim to document calcareous nannoplankton assemblage changes across the early-middle Eocene transition, in order to upset the biostratigraphic framework and to increase comprehension of how phytoplankton communities responded to paleoenvironmental changes at that time. The sedimentary successions recovered at IODP Site U1410 (Exp. 342; 41˚ 19.6987'N; 49˚ 10.1995'W, Norris et al., 2012) on the Southeast Newfoundland Ridge (NW Atlantic) offer an expanded record of the early-middle Eocene interval that is marked by an increase in accumulation rate related to sedimentation of clay-rich nannofossil oozes. Quantitative analysis of calcareous nannofossil assemblages was conducted, encompassing calcareous nannofossil Zones NP12 -NP15 or CNE4-CNE10 (Martini, 1971; Agnini et al., 2014). The study interval records the appearance and proliferation of Noelaerhabdaceae family (i.e, Reticulofenestra/Dictyococcites group), which can be considered one of the most significant shifts in the assemblage structure of the Paleogene. This change was probably favored by modifications in surface water chemistry. The middle Eocene clay-rich sediments contain well preserved

  4. Tectonic growth of a Cretaceous-Eocene accretionary orogen formed at the southern margin of the Caribbean Plate: integrated geological insights from northernmost Colombia (United States)

    Cardona, A.; Weber, M. B.; Bayona, G.; Jaramillo, C.; Montes, C.; Ojeda, G.; Duque, J. F.; Salazar, C. A.


    Geological characteristics from the Cretaceous to Eocene metamorphic and igneous basement rocks from the Guajira and the NW corner of the Sierra Nevada de Santa Marta massifs in the northern Colombian Caribbean region, and the stratigraphy of adjacent basins, reveal different stages of growth of a segmented Late Cretaceous to Eocene accretionary orogen formed by interaction between the NW margin of South America and the Caribbean plate. Extensive intercalations of metavolcano-sedimentary rocks in the Santa Marta region, chemical composition of spinels and pyroxenes from serpentinized mantle tectonites and gabbros, as well as whole rock geochemistry from basaltic dykes from the Guajira massifs, record the evolution of a Cretaceous intra-oceanic arc in a succesion of Mariana- and Chile-type subduction styles. Geological and positive gravity signatures suggest that this arc was accreted and tectonically underplated to the continental margin of South America, creating a Maastrichian-Paleocene syn-orogenic basin, presently cropping out in the Cesar-Rancheria valley. After this collisional event, subduction of the Caribbean plate under South America started, as revealed by intrusion of composite stitched Late Paleocene-Eocene granitoids in the NW corner of the SNSM and Guajira massifs. These plutons show continental calc-alkaline geochemical signatures and more evolved Sr and Nd isotopic compositions than juvenile and older intra-oceanic arc magmatic rocks. This new subduction environment is linked to the convergence between North and South America at this time. Low pressure estimations and fast cooling rates between 450-250° for the Eocene granitoids in the Guajira and Santa Marta regions, indicate shallow < 7 Km depths of intrusion. Local unconformable stratigraphic relationships with Eocene-Miocene sediments at the Guajira region and overimposed post-magmatic low temperature deformation in some of these granitoids suggest an important Late Eocene unroofing and

  5. Origen y evolución de los Platyrrhini (Primates, Anthropoidea, con especial referencia a los registros de Argentina

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    Tejedor, M. F.


    Full Text Available The are new light about the Platyrrhini origin provided by the fossil record of the Old World, which demonstrates that catarrhines and platyrrhines are certainly a monophyletic group. Although the exact provenance of the Platyrrhini is uncertain at this time, some characters of the latter are shared with primitive anthropoid primates from the Fayum Depression, in the Egyptian late Eocene-early Oligocene, and then we can accept an African origin for platyrrhines. Symplesiomorphies exhibited by these two groups imply that the New World monkeys could be recognised morphologically more conservative. The evolutionary history of the Infraorder Platyrrhini has been a source of discussion, especially in recent years when the fossil record has increased dramatically. These advances contributed to a better understanding of their diversity and, on the other hand, the fossil diversity demonstrates that the living platyrrhines are a result of several evolutionary trends since the late Oligocene of South America. Fossil evidences come from several localities of South America and the Caribbean islands. The Patagonian fossil record includes specimens that show many particular characters not found among other fossil or living platyrrhines. Some living groups demonstrate close affinities with fossil relatives, such as those from La Venta, Colombia, and with a few specimens of Patagonia, while others are considered as part of a broad range of adaptive diversity whose extinct relatives are still unknown.Las recientes evidencias sobre el origen del suborden Anthropoidea proceden principalmente del Viejo Mundo, en especial de Africa y Asia, y podría afirmarse que dicho suborden constituye un grupo monofilético que incluye a catarrinos y platirrinos. Existen ciertas relaciones entre algunos primitivos Anthropoidea del Oligoceno egipcio del Fayum y los platirrinos, simplesiomorfías retenidas desde un origen común de ambos grupos, y demuestran que los platirrinos

  6. Primate Drum Kit: A System for Studying Acoustic Pattern Production by Non-Human Primates Using Acceleration and Strain Sensors

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    W. Tecumseh Fitch


    Full Text Available The possibility of achieving experimentally controlled, non-vocal acoustic production in non-human primates is a key step to enable the testing of a number of hypotheses on primate behavior and cognition. However, no device or solution is currently available, with the use of sensors in non-human animals being almost exclusively devoted to applications in food industry and animal surveillance. Specifically, no device exists which simultaneously allows: (i spontaneous production of sound or music by non-human animals via object manipulation, (ii systematical recording of data sensed from these movements, (iii the possibility to alter the acoustic feedback properties of the object using remote control. We present two prototypes we developed for application with chimpanzees (Pan troglodytes which, while fulfilling the aforementioned requirements, allow to arbitrarily associate sounds to physical object movements. The prototypes differ in sensing technology, costs, intended use and construction requirements. One prototype uses four piezoelectric elements embedded between layers of Plexiglas and foam. Strain data is sent to a computer running Python through an Arduino board. A second prototype consists in a modified Wii Remote contained in a gum toy. Acceleration data is sent via Bluetooth to a computer running Max/MSP. We successfully pilot tested the first device with a group of chimpanzees. We foresee using these devices for a range of cognitive experiments.

  7. Chromosomal evolution of the PKD1 gene family in primates

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    Krawczak Michael


    Full Text Available Abstract Background The autosomal dominant polycystic kidney disease (ADPKD is mostly caused by mutations in the PKD1 (polycystic kidney disease 1 gene located in 16p13.3. Moreover, there are six pseudogenes of PKD1 that are located proximal to the master gene in 16p13.1. In contrast, no pseudogene could be detected in the mouse genome, only a single copy gene on chromosome 17. The question arises how the human situation originated phylogenetically. To address this question we applied comparative FISH-mapping of a human PKD1-containing genomic BAC clone and a PKD1-cDNA clone to chromosomes of a variety of primate species and the dog as a non-primate outgroup species. Results Comparative FISH with the PKD1-cDNA clone clearly shows that in all primate species studied distinct single signals map in subtelomeric chromosomal positions orthologous to the short arm of human chromosome 16 harbouring the master PKD1 gene. Only in human and African great apes, but not in orangutan, FISH with both BAC and cDNA clones reveals additional signal clusters located proximal of and clearly separated from the PKD1 master genes indicating the chromosomal position of PKD1 pseudogenes in 16p of these species, respectively. Indeed, this is in accordance with sequencing data in human, chimpanzee and orangutan. Apart from the master PKD1 gene, six pseudogenes are identified in both, human and chimpanzee, while only a single-copy gene is present in the whole-genome sequence of orangutan. The phylogenetic reconstruction of the PKD1-tree reveals that all human pseudogenes are closely related to the human PKD1 gene, and all chimpanzee pseudogenes are closely related to the chimpanzee PKD1 gene. However, our statistical analyses provide strong indication that gene conversion events may have occurred within the PKD1 family members of human and chimpanzee, respectively. Conclusion PKD1 must have undergone amplification very recently in hominid evolution. Duplicative

  8. Primate brain architecture and selection in relation to sex. (United States)

    Lindenfors, Patrik; Nunn, Charles L; Barton, Robert A


    Social and competitive demands often differ between the sexes in mammals. These differing demands should be expected to produce variation in the relative sizes of various brain structures. Sexual selection on males can be predicted to influence brain components handling sensory-motor skills that are important for physical competition or neural pathways involving aggression. Conversely, because female fitness is more closely linked to ecological factors and social interactions that enable better acquisition of resources, social selection on females should select for brain components important for navigating social networks. Sexual and social selection acting on one sex could produce sexual dimorphism in brain structures, which would result in larger species averages for those same brain structures. Alternatively, sex-specific selection pressures could produce correlated effects in the other sex, resulting in larger brain structures for both males and females of a species. Data are presently unavailable for the sex-specific sizes of brain structures for anthropoid primates, but under either scenario, the effects of sexual and social selection should leave a detectable signal in average sizes of brain structures for different species. The degree of male intra-sexual selection was positively correlated with several structures involved in autonomic functions and sensory-motor skills, and in pathways relating to aggression and aggression control. The degree of male intra-sexual selection was not correlated with relative neocortex size, which instead was significantly positively correlated with female social group size, but negatively correlated with male group size. Sexual selection on males and social selection on females have exerted different effects on primate brain architecture. Species with a higher degree of male intra-sexual selection carry a neural signature of an evolutionary history centered on physical conflicts, but no traces of increased demands on

  9. Genome-wide comparative analysis of microRNAs in three non-human primates

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    Brameier Markus


    Full Text Available Abstract Background MicroRNAs (miRNAs are negative regulators of gene expression in multicellular eukaryotes. With the recently completed sequencing of three primate genomes, the study of miRNA evolution within the primate lineage has only begun and may be expected to provide the genetic and molecular explanations for many phenotypic differences between human and non-human primates. Findings We scanned all three genomes of non-human primates, including chimpanzee (Pan troglodytes, orangutan (Pongo pygmaeus, and rhesus monkey (Macaca mulatta, for homologs of human miRNA genes. Besides sequence homology analysis, our comparative method relies on various postprocessing filters to verify other features of miRNAs, including, in particular, their precursor structure or their occurrence (prediction in other primate genomes. Our study allows direct comparisons between the different species in terms of their miRNA repertoire, their evolutionary distance to human, the effects of filters, as well as the identification of common and species-specific miRNAs in the primate lineage. More than 500 novel putative miRNA genes have been discovered in orangutan that show at least 85 percent identity in precursor sequence. Only about 40 percent are found to be 100 percent identical with their human ortholog. Conclusion Homologs of human precursor miRNAs with perfect or near-perfect sequence identity may be considered to be likely functional in other primates. The computational identification of homologs with less similar sequence, instead, requires further evidence to be provided.

  10. Different scaling of white matter volume, cortical connectivity, and gyrification across rodent and primate brains (United States)

    Ventura-Antunes, Lissa; Mota, Bruno; Herculano-Houzel, Suzana


    Expansion of the cortical gray matter in evolution has been accompanied by an even faster expansion of the subcortical white matter volume and by folding of the gray matter surface, events traditionally considered to occur homogeneously across mammalian species. Here we investigate how white matter expansion and cortical folding scale across species of rodents and primates as the gray matter gains neurons. We find very different scaling rules of white matter expansion across the two orders, favoring volume conservation and smaller propagation times in primates. For a similar number of cortical neurons, primates have a smaller connectivity fraction and less white matter volume than rodents; moreover, as the cortex gains neurons, there is a much faster increase in white matter volume and in its ratio to gray matter volume in rodents than in primates. Order-specific scaling of the white matter can be attributed to different scaling of average fiber caliber and neuronal connectivity in rodents and primates. Finally, cortical folding increases as different functions of the number of cortical neurons in rodents and primates, scaling faster in the latter than in the former. While the neuronal rules that govern gray and white matter scaling are different across rodents and primates, we find that they can be explained by the same unifying model, with order-specific exponents. The different scaling of the white matter has implications for the scaling of propagation time and computational capacity in evolution, and calls for a reappraisal of developmental models of cortical expansion in evolution. PMID:23576961

  11. Conservation strategies for understanding and combating the primate bushmeat trade on Bioko Island, Equatorial Guinea. (United States)

    Cronin, Drew T; Sesink Clee, Paul R; Mitchell, Matthew W; Bocuma Meñe, Demetrio; Fernández, David; Riaco, Cirilo; Fero Meñe, Maximiliano; Esara Echube, Jose Manuel; Hearn, Gail W; Gonder, Mary Katherine


    Bioko Island, Equatorial Guinea is among the important places in Africa for the conservation of primates, but a cultural preference for bushmeat and a lack of effective law enforcement has encouraged commercial bushmeat hunting, threatening the survival of the remaining primate population. For over 13 years, we collected bushmeat market data in the Malabo market, recording over 35,000 primate carcasses, documenting "mardi gras" consumption patterns, seasonal carcass availability, and negative effects resulting from government intervention. We also conducted forest surveys throughout Bioko's two protected areas in order to localize and quantify primate populations and hunting pressure. Using these data, we were able to document the significant negative impact bushmeat hunting had on monkey populations, estimate which species are most vulnerable to hunting, and develop ecological niche models to approximate the distribution of each of Bioko's diurnal primate species. These results also have allowed for the identification of primate hotspots, such as the critically important southwest region of the Gran Caldera Scientific Reserve, and thus, priority areas for conservation on Bioko, leading to more comprehensive conservation recommendations. Current and future efforts now focus on bridging the gap between investigators and legislators in order to develop and effectively implement a management plan for Bioko's Gran Caldera Scientific Reserve and to develop a targeted educational campaign to reduce demand by changing consumer attitudes toward bushmeat. Using this multidisciplinary approach, informed by biological, socioeconomic, and cultural research, there may yet be a positive future for the primates of Bioko. © 2017 Wiley Periodicals, Inc.

  12. Response of frugivorous primates to changes in fruit supply in a northern Amazonian forest. (United States)

    Mourthé, I


    Few attempts have been made to understand how spatiotemporal changes in fruit supply influence frugivores in tropical forests. The marked spatiotemporal variation in fruit supply can affect frugivore abundance and distribution, but studies addressing the effects of this variation on primates are scarce. The present study aimed to investigate how the spatiotemporal distribution of fruits influences the local distribution of three frugivorous primates in the eastern part of the Maracá Ecological Station, a highly seasonal Amazonian rainforest. Specifically, it was hypothesised that primate distribution will track changes in fruit supply, resulting that sites with high fruit availability should be heavily used by primates. During a 1-year study, fruit supply (ground fruit surveys) and primate density (line-transects) were monitored in twelve 2 km-long transects at monthly intervals. Fruit supply varied seasonally, being low during the dry season. The density of Ateles belzebuth was positively related to fruit supply during fruit shortage, but Cebus olivaceus and Alouatta macconnelli did not follow the same pattern. The supply of Sapotaceae fruit was an important component determining local distribution of A. belzebuth during the overall fruit shortage. Highly frugivorous primates such as A. belzebuth respond to seasonal decline in fruit supply by congregating at places with high fruit supply in this forest, particularly, those with many individuals of species of Sapotaceae. This study underscores the importance of small-scale spatiotemporal changes of fruit supply as a key component of frugivorous primate ecology in highly seasonal environments.

  13. Seroprevalence of Hepatitis A virus infection in non-human primates in Assam, India

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    B.G. Nath


    Full Text Available The present study investigated 37 serum samples of non-human primates in Assam State Zoo and the Department of Forest and Environment, Govt. of Assam for seroprevalence of hepatitis A virus infection during the period from December, 2007 to November, 2009. Four serum samples were also collected from animal keepers of the zoo to investigate transmission of the disease to the attendants working with these primates. Competitive ELISA was performed using hepatitis A virus ELISA kit (Wanti Hep. AV to detect hepatitis A virus antibody in serum samples. Ten (27.21% of the non-human primate samples and three (75% human samples had detectable anti-hepatitis A virus antibodies. Living status of the non-human primates (Free living was a high potential risk for hepatitis A virus infection. Seroprevalence of hepatitis A virus infection had significant difference between free living non-human primates and captive non-human primates (P less than 0.05. No significant difference (p=0.86 was seen between male and female non-human primates

  14. Evolutionary and Functional Analysis of Old World Primate TRIM5 Reveals the Ancient Emergence of Primate Lentiviruses and Convergent Evolution Targeting a Conserved Capsid Interface.

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    Kevin R McCarthy


    Full Text Available The widespread distribution of lentiviruses among African primates, and the lack of severe pathogenesis in many of these natural reservoirs, are taken as evidence for long-term co-evolution between the simian immunodeficiency viruses (SIVs and their primate hosts. Evidence for positive selection acting on antiviral restriction factors is consistent with virus-host interactions spanning millions of years of primate evolution. However, many restriction mechanisms are not virus-specific, and selection cannot be unambiguously attributed to any one type of virus. We hypothesized that the restriction factor TRIM5, because of its unique specificity for retrovirus capsids, should accumulate adaptive changes in a virus-specific fashion, and therefore, that phylogenetic reconstruction of TRIM5 evolution in African primates should reveal selection by lentiviruses closely related to modern SIVs. We analyzed complete TRIM5 coding sequences of 22 Old World primates and identified a tightly-spaced cluster of branch-specific adaptions appearing in the Cercopithecinae lineage after divergence from the Colobinae around 16 million years ago. Functional assays of both extant TRIM5 orthologs and reconstructed ancestral TRIM5 proteins revealed that this cluster of adaptations in TRIM5 specifically resulted in the ability to restrict Cercopithecine lentiviruses, but had no effect (positive or negative on restriction of other retroviruses, including lentiviruses of non-Cercopithecine primates. The correlation between lineage-specific adaptations and ability to restrict viruses endemic to the same hosts supports the hypothesis that lentiviruses closely related to modern SIVs were present in Africa and infecting the ancestors of Cercopithecine primates as far back as 16 million years ago, and provides insight into the evolution of TRIM5 specificity.

  15. A Critical Evaluation of High TEX86-derived Sea Surface Temperatures from the Early Eocene (United States)

    Pancost, R. D.; Taylor, K. W.; Handley, L.; Huber, M.; Hollis, C. J.


    The application of glycerol dialkyl glycerol tetraether (GDGT) based sea surface temperature proxies (eg TEX-86) has brought about major advances in our understanding of Cenozoic climate. However, TEX-86 approaches yield high temperatures at high latitudes during the EECO, and the resulting low latitudinal temperature gradients challenge our understanding of the physical climate system. We examine existing Paleogene TEX-86 data using three approaches. First, we have compared TEX-86 SST estimates to those derived from oxygen isotopes or Mg/Ca ratios of co-occurring well-preserved planktonic foraminifera. This reveals a strong correlation between foraminiferal SSTs and those obtained from linear TEX-86 calibrations, but the latter are systematically 4-6°C warmer. SSTs derived from non-linear TEX-86 calibrations are similar to inorganic SST estimates at high temperatures, but an offset still persists at lower temperatures. We have also compared TEX-86 SST estimates from marginal settings to associated continental mean air temperatures (MAT) derived from soil bacterial GDGTs (the MBT/CBT index). Again, the two approaches exhibit a strong correlation but with the former yielding 4-6°C warmer temperatures. Second, we have developed SST records from New Zealand, in order to place the EECO SSTs into a longer-term Paleogene context. Our temperature estimates indicate that sea floor and sea surface temperatures increased by ~10°C from late Paleocene to early Eocene times. Late Paleocene TEX-86-derived SSTs for the Canterbury Basin range from 18 to 23°C, consistent with coeval TEX-86 records from the Campbell Plateau and south Tasman Sea. During the EECO, TEX-86 derived SSTs from the Canterbury Basin and south Tasman Sea indicate tropical conditions, with temperatures peaking at 30-32°C at 50 Ma and then declining to 24-26°C into the Middle Eocene. MBT/CBT-derived MATs broadly parallel the SST trends, albeit with slightly lower values. These records suggest that

  16. Exploring the controls on element ratios in middle Eocene samples of the benthic foraminifera Oridorsalis umbonatus

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    C. F. Dawber


    Full Text Available Culturing studies and empirically based core top calibrations have been used to infer that elemental ratios in benthic foraminifera can be used as proxies to reconstruct past variations in bottom water temperature and saturation state (Δ [CO32−]. However the mechanisms linking elemental ratios to these parameters are poorly constrained. Here, we explore the environmental parameters influencing the incorporation of B, Li, Sr and Mg in Oridorsalis umbonatus in early Cenozoic sediments from Ocean Drilling Program Site 1209. We investigate the influence of middle Eocene variations in intermediate water Δ [CO32−] using relationships developed from core top samples. The fidelity of bottom water Δ[CO32−] reconstructions based on single element ratios is assessed by comparing the X/Ca-based reconstructions to each other and to carbon cycle proxy records (benthic foraminifera δ13C, organic carbon content, foraminifera dissolution indices, and a seawater δ18O reconstruction for Site 1209. Discrepancies in the reconstructed Δ[CO32−] values based on these different metal ratios suggest that there are still gaps in our understanding of the parameters influencing X/Ca and demonstrate that caution is required when interpreting palaeo-reconstructions that are derived from a single elemental ratio. The downcore record of O. umbonatus Mg/Ca does not exhibit any similarities with the Li/Ca, B/Ca and Sr/Ca records, suggesting that the environmental parameters influencing Mg/Ca may be different for this species, consistent with temperature as the strongest control on this elemental ratio. This hypothesis is supported by the coefficients of multiple linear regression models on published Mg/Ca data. An incomplete understanding of the controls on elemental incorporation into benthic foraminifera hinders our ability to confidently quantify changes in saturation state using single X/Ca reconstructions over a range of timescales.

  17. Transition of Eocene whales from land to sea: evidence from bone microstructure.

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    Alexandra Houssaye

    Full Text Available Cetacea are secondarily aquatic amniotes that underwent their land-to-sea transition during the Eocene. Primitive forms, called archaeocetes, include five families with distinct degrees of adaptation to an aquatic life, swimming mode and abilities that remain difficult to estimate. The lifestyle of early cetaceans is investigated by analysis of microanatomical features in postcranial elements of archaeocetes. We document the internal structure of long bones, ribs and vertebrae in fifteen specimens belonging to the three more derived archaeocete families--Remingtonocetidae, Protocetidae, and Basilosauridae--using microtomography and virtual thin-sectioning. This enables us to discuss the osseous specializations observed in these taxa and to comment on their possible swimming behavior. All these taxa display bone mass increase (BMI in their ribs, which lack an open medullary cavity, and in their femora, whereas their vertebrae are essentially spongious. Humeri and femora show opposite trends in microanatomical specialization in the progressive independence of cetaceans from a terrestrial environment. Humeri change from very compact to spongious, which is in accordance with the progressive loss of propulsive role for the forelimbs, which were used instead for steering and stabilizing. Conversely, hind-limbs in basilosaurids became strongly reduced with no involvement in locomotion but display strong osteosclerosis in the femora. Our study confirms that Remingtonocetidae and Protocetidae were almost exclusively aquatic in locomotion for the taxa sampled, which probably were shallow water suspended swimmers. Basilosaurids display osseous specializations similar to those of modern cetaceans and are considered more active open-sea swimmers. This study highlights the strong need for homologous sections in comparative microanatomical studies, and the importance of combining information from several bones of the same taxon for improved functional

  18. A middle Eocene mesoeucrocodylian (Crocodyliformes) from the Kaninah Formation, Republic of Yemen (United States)

    Stevens, Nancy J.; Hill, Robert V.; Al-Wosabi, Mohammed; Schulp, Anne; As-Saruri, Mustafa; Al-Nimey, Fuad; Jolley, Lea Ann; Schulp-Stuip, Yvonne; O'Connor, Patrick


    During the Cenozoic, the Arabian Plate separated from continental Africa and assumed a closer geographical relationship with Eurasia. As such, the vertebrate fossil record of the Arabian Peninsula has great potential for documenting faunal interchanges that occurred as a result of such tectonic events, with a shift from a primarily Afro-Arabian fauna in the Palaeogene to a more cosmopolitan fauna in the Neogene. Understanding of the sequence and timing of this faunal interchange has long been hampered by a lack of palaeontological data. Recently recovered fossils from the Middle Eocene Kaninah Formation of Yemen constitute the earliest Palaeogene record of continental vertebrates from the Arabian Peninsula, thereby offering a rare glimpse at the region's post- -Cretaceous fauna. Here we describe fossil materials from the Kaninah Formation, a collection of dental and postcranial elements representing a mesoeucrocodylian crocodyliform of unclear affinities. The specimen exhibits ziphodont tooth morphology along with a biserial paravertebral shield and polygonal gastral osteoderms, consistent with certain mesoeucrocodylians (e.g., ziphodontan notosuchians). Yet the associated fragmentary anterior caudal vertebra, although badly abraded, preserves morphology suggestive of procoely. This vertebral type in combination with the dental and osteoderm morphology is much more taxonomically restrictive and consistent with the suite of characters exhibited by atoposaurids, a finding that would significantly extend that clade through the Cretaceous/Palaeogene boundary. Alternatively, given the relative paucity of information from the region during the Palaeogene, the combination of characteristics of the Kaninah crocodyliform may reflect a novel or poorly known form exhibiting previously unrecognised character mosaicism. We take a conservative approach, and refer the Kaninah specimen to Mesoeucrocodylia, Atoposauridae (?) pending discovery of more complete material. New fossils


    Ferràndez-Cañadell, Carles; Briguglio, Antonino; Hohenegger, Johann; Wöger, Julia


    In foraminifera, so-called “double tests” usually arise due to abnormal growth originating mainly from twinning, but may also be caused by irregularities in the early chambers and by regeneration after test injury that modifies the direction of growth. A fourth cause of double tests has only rarely been reported: the fusion of the tests of two adult individuals. We studied an early Eocene Nummulites double test consisting of two adult individuals that fused after an extended period of independent growth. The specimen was studied using computed tomography with micrometric resolution (micro-CT) that allowed bi- and three-dimensional visualization of the internal structure. Before fusion each individual test had 30–36 chambers, which, by comparison with growth rates in recent nummulitids, implies at least three months of independent growth. After fusion, the compound test grew in two spirals that fused after about one whorl and then continued in a single spiral. To fuse their tests, either adult individuals have to be forced to do so or the allorecognition (ability to distinguish between self and another individual) mechanisms must fail. A possible explanation for the merged Nummulites tests in this study is forced fusion in attached individuals after surviving ingestion and digestion by a metazoan. Alternatively, environmental stress could lead to a failure of allorecognition mechanisms and/or foraminiferal motility. Once fused, subsequent growth seems to be determined mainly by the relative orientation of individual tests. In any case, the frequency in which adult fusion occurs remains unknown. PMID:26166916

  20. The Eocene South American metatherian Zeusdelphys complicatus is not a protodidelphidid but a hatcheriform: Paleobiogeographic implications

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    Leonardo M. Carneiro


    Full Text Available Zeusdelphys complicatus is one of the most enigmatic metatherians from the Itaboraí Basin. The type and only known specimen was previously regarded as the upper dentition of Eobrasilia; an M4 of a new taxon; an M3 of a Kollpaniidae (now regarded as a group of “condylarths”; a probable M1 of an incertae sedis taxon; and as an M1 of a Protodidelphidae. Herein, we present a morphological review of the dental structures of Zeusdelphys complicatus, presenting new interpretations and comparing it with other North and South American taxa. We also perform a phylogenetic analysis in order to test the affinities of Zeusdelphys and the validity of most studied characters. The results recovered Zeusdelphys complicatus as more closely related to Hatcheritherium alpha than to any other metatherian. Glasbiidae were recovered as the sister lineage of Protodidelphidae within Didelphimorphia, as true marsupials. Ectocentrocristus was recovered as the sister taxon of Zeusdelphys + Hatcheritherium, as a Hatcheriformes. The analysis recovered this suborder as an independent lineage from Polydolopimorphia, being more closely related to “Alphadontidae”. The affinities with Protodidelphidae are a result of convergent evolution, as Zeusdelphys is more closely related to Hatcheritherium alpha from the Late Cretaceous of North America. The results support a North American origin for Hatcheriformes. The presence of strong sea-level lowstands and islands in the Caribbean Plate during the Late Cretaceous provide valid data to support a faunal interchange between Americas during the latest Late Cretaceous. Based on the results, Zeusdelphys represents a South American early Eocene surviving Hatcheriformes.

  1. Hydrological and associated biogeochemical consequences of rapid global warming during the Paleocene-Eocene Thermal Maximum (United States)

    Carmichael, Matthew J.; Inglis, Gordon N.; Badger, Marcus P. S.; Naafs, B. David A.; Behrooz, Leila; Remmelzwaal, Serginio; Monteiro, Fanny M.; Rohrssen, Megan; Farnsworth, Alexander; Buss, Heather L.; Dickson, Alexander J.; Valdes, Paul J.; Lunt, Daniel J.; Pancost, Richard D.


    The Paleocene-Eocene Thermal Maximum (PETM) hyperthermal, 56 million years ago (Ma), is the most dramatic example of abrupt Cenozoic global warming. During the PETM surface temperatures increased between 5 and 9 °C and the onset likely took < 20 kyr. The PETM provides a case study of the impacts of rapid global warming on the Earth system, including both hydrological and associated biogeochemical feedbacks, and proxy data from the PETM can provide constraints on changes in warm climate hydrology simulated by general circulation models (GCMs). In this paper, we provide a critical review of biological and geochemical signatures interpreted as direct or indirect indicators of hydrological change at the PETM, explore the importance of adopting multi-proxy approaches, and present a preliminary model-data comparison. Hydrological records complement those of temperature and indicate that the climatic response at the PETM was complex, with significant regional and temporal variability. This is further illustrated by the biogeochemical consequences of inferred changes in hydrology and, in fact, changes in precipitation and the biogeochemical consequences are often conflated in geochemical signatures. There is also strong evidence in many regions for changes in the episodic and/or intra-annual distribution of precipitation that has not widely been considered when comparing proxy data to GCM output. Crucially, GCM simulations indicate that the response of the hydrological cycle to the PETM was heterogeneous - some regions are associated with increased precipitation - evaporation (P - E), whilst others are characterised by a decrease. Interestingly, the majority of proxy data come from the regions where GCMs predict an increase in PETM precipitation. We propose that comparison of hydrological proxies to GCM output can be an important test of model skill, but this will be enhanced by further data from regions of model-simulated aridity and simulation of extreme precipitation

  2. Eocene-Pliocene deep sea ostracodes from ODP site 744A, Southern Indian Ocean

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    Cristianini T. Bergue


    Full Text Available The Eocene-Pliocene deep sea ostracodes from the ODP site 744A (Kerguelen Plateau are herein studied under the taxonomic and paleoecologic aspects. 28 species are identified, being the genera Krithe, Cytherella and Dutoitella the most diversified. A faunal threshold was recorded in the Early Oligocene, which is tentatively explained under the knowledge of the paleoceanographical studies carried out not only in the Kerguelen Plateau but also in adjacent areas. The faunal turnover and variations in both richness and abundance possibly reflect the inception of psychrosphere and the influence of hydrological changes in the preservation of carapaces. Moreover, the influence of those changes on carbonate preservation is discussed as the cause of faunal impoverishment in the upper portion of the core.Ostracodes do intervalo Eoceno-Plioceno do sítio 744A do ODP (Platô Kerguelen são aqui estudados sob o aspecto taxonômico e paleoecológico. 28 espécies são identificadas, sendo os gêneros Krithe, Cytherella e Dutoitella os mais diversificados. Uma transição faunística registrada no Eoligoceno é investigada com base em estudos paleoceanográficos realizados no Platô Kerguelen e em áreas adjacentes. A transição e as variações de riqueza e abundância possivelmente refletem o estabelecimento da psicrosfera e mudanças hidrológicas associadas, na composição da fauna. Além disso, a influência destas mudanças na preservação do carbonato é discutida comopossível causa do empobrecimento da fauna na porção superior do testemunho.

  3. Eocene habitat shift from saline to freshwater promoted Tethyan amphipod diversification (United States)

    Hou, Zhonge; Sket, Boris; Fišer, Cene; Li, Shuqiang


    Current theory predicts that a shift to a new habitat would increase the rate of diversification, while as lineages evolve into multiple species, intensified competition would decrease the rate of diversification. We used Holarctic amphipods of the genus Gammarus to test this hypothesis. We sequenced four genes (5,088 bp) for 289 samples representing 115 Gammarus species. A phylogenetic analysis showed that Gammarus originated from the Tethyan region with a saline ancestry in the Paleocene, and later colonized the freshwater habitat in the Middle Eocene. Ancestral range reconstruction and diversification mode analysis combined with paleogeological and paleoclimatic evidence suggested that the habitat shift from saline to freshwater led to an increased diversification rate. The saline lineage of Gammarus dispersed to both sides of the Atlantic at 55 million years ago (Ma), because of the few barriers between the Tethys and the Atlantic, and diversified throughout its evolutionary history with a constant diversification rate [0.04 species per million years (sp/My)]. The freshwater Gammarus, however, underwent a rapid diversification phase (0.11 sp/My) until the Middle Miocene, and lineages successively diversified across Eurasia via vicariance process likely driven by changes of the Tethys and landmass. In particular, the freshwater Gammarus lacustris and Gammarus balcanicus lineages had a relatively high diversification shift, corresponding to the regression of the Paratethys Sea and the continentalization of Eurasian lands during the Miocene period. Subsequently (14 Ma), the diversification rate of the freshwater Gammarus decreased to 0.05 and again to 0.01 sp/My. The genus Gammarus provides an excellent aquatic case supporting the hypothesis that ecological opportunities promote diversification. PMID:21844362

  4. Chemistry of the Marlboro Clay in Virginia and Implications for the Paleocene-Eocene Thermal Maximum (United States)

    Zimmer, M.; Cai, Y.; Corley, A.; Liang, J. A.; Powars, D.; Goldstein, S. L.; Kent, D. V.; Broecker, W. S.


    The Paleocene-Eocene Thermal Maximum (PETM) was a global hyperthermal ( 5ºC warming) event marked by a rapid carbon isotope excursion (CIE) of >1‰ in the marine carbonate record (e.g. Zeebe et al. Nature Geoscience 2009). Possible explanations for the CIE include intrusion of a sill complex into organic carbonate (Aarnes et al. J. Geol. Soc. 2015), dissolution of methane hydrates (Thomas et al. Geology 2002), and a comet impact event (Schaller et al. Science 2016). Here we present new data across the PETM from the VirginiaDEQ-USGS Surprise Hill (SH) core, Northumberland Co., VA. We analyzed the Marlboro Clay, a thick, kaolinite-rich clay unit that marks the initiation of the PETM in the mid-Atlantic Coastal Plain of North America, as well as units above and below it. Bulk sediment records a δ13C excursion of approximately -5‰ across the CIE, while benthic foraminifera (Cibicidoides spp.) record a synchronous excursion of approximately -4.5‰. These results are consistent with other records from the New Jersey Coastal Plain (Makarova et al. Paleoceanography 2017). The excursion coincides with an increase in magnetic susceptibility, a decrease in bulk CaCO3 content, and an 2.5‰ decrease of δ18O in both the bulk sediment and benthic foraminifera of the SH core. Pb isotope analyses of the <63 μm fraction sediments indicate a unique provenance make-up for the Marlboro Clay. The results of the study thus indicate that PETM Marlboro Clay was not generated simply by intensified weathering of the same source area as the underlying Aquia Formation and overlying Nanjemoy Formation. Any hypothesis that aims to explain the mechanism that triggered the PETM must also account for the observed distinct provenance make-up of the Marlboro Clay.

  5. Warm Paleocene/Eocene climate as simulated in ECHAM5/MPI-OM

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    M. Heinemann


    Full Text Available We investigate the late Paleocene/early Eocene (PE climate using the coupled atmosphere-ocean-sea ice model ECHAM5/MPI-OM. The surface in our PE control simulation is on average 297 K warm and ice-free, despite a moderate atmospheric CO2 concentration of 560 ppm. Compared to a pre-industrial reference simulation (PR, low latitudes are 5 to 8 K warmer, while high latitudes are up to 40 K warmer. This high-latitude amplification is in line with proxy data, yet a comparison to sea surface temperature proxy data suggests that the Arctic surface temperatures are still too low in our PE simulation.

    To identify the mechanisms that cause the PE-PR surface temperature differences, we fit two simple energy balance models to the ECHAM5/MPI-OM results. We find that about 2/3 of the PE-PR global mean surface temperature difference are caused by a smaller clear sky emissivity due to higher atmospheric CO2 and water vapour concentrations in PE compared to PR; 1/3 is due to a smaller planetary albedo. The reduction of the pole-to-equator temperature gradient in PE compared to PR is due to (1 the large high-latitude effect of the higher CO2 and water vapour concentrations in PE compared to PR, (2 the lower Antarctic orography, (3 the smaller surface albedo at high latitudes, and (4 longwave cloud radiative effects. Our results support the hypothesis that local radiative effects rather than increased meridional heat transports were responsible for the "equable" PE climate.

  6. An Eocene orthocone from Antarctica shows convergent evolution of internally shelled cephalopods.

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    Larisa A Doguzhaeva

    Full Text Available The Subclass Coleoidea (Class Cephalopoda accommodates the diverse present-day internally shelled cephalopod mollusks (Spirula, Sepia and octopuses, squids, Vampyroteuthis and also extinct internally shelled cephalopods. Recent Spirula represents a unique coleoid retaining shell structures, a narrow marginal siphuncle and globular protoconch that signify the ancestry of the subclass Coleoidea from the Paleozoic subclass Bactritoidea. This hypothesis has been recently supported by newly recorded diverse bactritoid-like coleoids from the Carboniferous of the USA, but prior to this study no fossil cephalopod indicative of an endochochleate branch with an origin independent from subclass Bactritoidea has been reported.Two orthoconic conchs were recovered from the Early Eocene of Seymour Island at the tip of the Antarctic Peninsula, Antarctica. They have loosely mineralized organic-rich chitin-compatible microlaminated shell walls and broadly expanded central siphuncles. The morphological, ultrustructural and chemical data were determined and characterized through comparisons with extant and extinct taxa using Scanning Electron Microscopy/Energy Dispersive Spectrometry (SEM/EDS.Our study presents the first evidence for an evolutionary lineage of internally shelled cephalopods with independent origin from Bactritoidea/Coleoidea, indicating convergent evolution with the subclass Coleoidea. A new subclass Paracoleoidea Doguzhaeva n. subcl. is established for accommodation of orthoconic cephalopods with the internal shell associated with a broadly expanded central siphuncle. Antarcticerida Doguzhaeva n. ord., Antarcticeratidae Doguzhaeva n. fam., Antarcticeras nordenskjoeldi Doguzhaeva n. gen., n. sp. are described within the subclass Paracoleoidea. The analysis of organic-rich shell preservation of A. nordenskjoeldi by use of SEM/EDS techniques revealed fossilization of hyposeptal cameral soft tissues. This suggests that a depositional environment

  7. Ceratopetalum (Cunoniaceae) fruits of Australasian affinity from the early Eocene Laguna del Hunco flora, Patagonia, Argentina. (United States)

    Gandolfo, María A; Hermsen, Elizabeth J


    Radially symmetrical, five-winged fossil fruits from the highly diverse early Eocene Laguna del Hunco flora of Chubut Province, Patagonia, Argentina, are named, described and illustrated. The main goals are to assess the affinities of the fossils and to place them in an evolutionary, palaeoecological and biogeographic context. Specimens of fossil fruits were collected from the Tufolitas Laguna del Hunco. They were prepared, photographed and compared with similar extant and fossil fruits using published literature. Their structure was also evaluated by comparing them with that of modern Ceratopetalum (Cunoniaceae) fruits through examination of herbarium specimens. The Laguna del Hunco fossil fruits share the diagnostic features that characterize modern and fossil Ceratopetalum (symmetry, number of fruit wings, presence of a conspicuous floral nectary and overall venation pattern). The pattern of the minor wing (sepal) veins observed in the Patagonian fossil fruits is different from that of modern and previously described fossil Ceratopetalum fruits; therefore, a new fossil species is recognized. An apomorphy (absence of petals) suggests that the fossils belong within crown-group Ceratopetalum . The Patagonian fossil fruits are the oldest known record for Ceratopetalum . Because the affinities, provenance and age of the fossils are so well established, this new Ceratopetalum fossil species is an excellent candidate for use as a calibration point in divergence dating studies of the family Cunoniaceae. It represents the only record of Ceratopetalum outside Australasia, and further corroborates the biogeographic connection between the Laguna del Hunco flora and ancient and modern floras of the Australasian region. © The Author 2017. Published by Oxford University Press on behalf of the Annals of Botany Company.

  8. Fire and ecosystem change in the Arctic across the Paleocene-Eocene Thermal Maximum (United States)

    Denis, Elizabeth H.; Pedentchouk, Nikolai; Schouten, Stefan; Pagani, Mark; Freeman, Katherine H.


    Fire has been an important component of ecosystems on a range of spatial and temporal scales. Fire can affect vegetation distribution, the carbon cycle, and climate. The relationship between climate and fire is complex, in large part because of a key role of vegetation type. Here, we evaluate regional scale fire-climate relationships during a past global warming event, the Paleocene-Eocene Thermal Maximum (PETM), in order to understand how vegetation influenced the links between climate and fire occurrence in the Arctic region. To document concurrent changes in climate, vegetation, and fire occurrence, we evaluated biomarkers, including polycyclic aromatic hydrocarbons (PAHs), terpenoids, and alkanes, from the PETM interval at a marine depositional site (IODP site 302, the Lomonosov Ridge) in the Arctic Ocean. Biomarker, fossil, and isotope evidence from site 302 indicates that terrestrial vegetation changed during the PETM. The abundance of the C29n-alkanes, pollen, and the ratio of leaf-wax n-alkanes relative to diterpenoids all indicate that proportional contributions from angiosperm vegetation increased relative to that from gymnosperms. These changes accompanied increased moisture transport to the Arctic and higher temperatures, as recorded by previously published proxy records. We find that PAH abundances were elevated relative to total plant biomarkers throughout the PETM, and suggest that fire occurrence increased relative to plant productivity. The fact that fire frequency or prevalence may have increased during wetter Arctic conditions suggests that changes in fire occurrence were not a simple function of aridity, as is commonly conceived. Instead, we suggest that the climate-driven ecological shift to angiosperm-dominated vegetation was what led to increased fire occurrence. Potential increases in terrestrial plant biomass that arose from warm, wet, and high CO2 conditions were possibly attenuated by biomass burning associated with compositional changes

  9. An Eocene orthocone from Antarctica shows convergent evolution of internally shelled cephalopods. (United States)

    Doguzhaeva, Larisa A; Bengtson, Stefan; Reguero, Marcelo A; Mörs, Thomas


    The Subclass Coleoidea (Class Cephalopoda) accommodates the diverse present-day internally shelled cephalopod mollusks (Spirula, Sepia and octopuses, squids, Vampyroteuthis) and also extinct internally shelled cephalopods. Recent Spirula represents a unique coleoid retaining shell structures, a narrow marginal siphuncle and globular protoconch that signify the ancestry of the subclass Coleoidea from the Paleozoic subclass Bactritoidea. This hypothesis has been recently supported by newly recorded diverse bactritoid-like coleoids from the Carboniferous of the USA, but prior to this study no fossil cephalopod indicative of an endochochleate branch with an origin independent from subclass Bactritoidea has been reported. Two orthoconic conchs were recovered from the Early Eocene of Seymour Island at the tip of the Antarctic Peninsula, Antarctica. They have loosely mineralized organic-rich chitin-compatible microlaminated shell walls and broadly expanded central siphuncles. The morphological, ultrustructural and chemical data were determined and characterized through comparisons with extant and extinct taxa using Scanning Electron Microscopy/Energy Dispersive Spectrometry (SEM/EDS). Our study presents the first evidence for an evolutionary lineage of internally shelled cephalopods with independent origin from Bactritoidea/Coleoidea, indicating convergent evolution with the subclass Coleoidea. A new subclass Paracoleoidea Doguzhaeva n. subcl. is established for accommodation of orthoconic cephalopods with the internal shell associated with a broadly expanded central siphuncle. Antarcticerida Doguzhaeva n. ord., Antarcticeratidae Doguzhaeva n. fam., Antarcticeras nordenskjoeldi Doguzhaeva n. gen., n. sp. are described within the subclass Paracoleoidea. The analysis of organic-rich shell preservation of A. nordenskjoeldi by use of SEM/EDS techniques revealed fossilization of hyposeptal cameral soft tissues. This suggests that a depositional environment favoring soft

  10. Transient dwarfism of soil fauna during the Paleocene-Eocene Thermal Maximum (United States)

    Smith, J.J.; Hasiotis, S.T.; Kraus, M.J.; Woody, D.T.


    Soil organisms, as recorded by trace fossils in paleosols of the Willwood Formation, Wyoming, show significant body-size reductions and increased abundances during the Paleocene-Eocene Thermal Maximum (PETM). Paleobotanical, paleopedologic, and oxygen isotope studies indicate high temperatures during the PETM and sharp declines in precipitation compared with late Paleocene estimates. Insect and oligochaete burrows increase in abundance during the PETM, suggesting longer periods of soil development and improved drainage conditions. Crayfish burrows and molluscan body fossils, abundant below and above the PETM interval, are significantly less abundant during the PETM, likely because of drier floodplain conditions and lower water tables. Burrow diameters of the most abundant ichnofossils are 30-46% smaller within the PETM interval. As burrow size is a proxy for body size, significant reductions in burrow diameter suggest that their tracemakers were smaller bodied. Smaller body sizes may have resulted from higher subsurface temperatures, lower soil moisture conditions, or nutritionally deficient vegetation in the high-CO2 atmosphere inferred for the PETM. Smaller soil fauna co-occur with dwarf mammal taxa during the PETM; thus, a common forcing mechanism may have selected for small size in both above- and below-ground terrestrial communities. We predict that soil fauna have already shown reductions in size over the last 150 years of increased atmospheric CO2 and surface temperatures or that they will exhibit this pattern over the next century. We retrodict also that soil fauna across the Permian-Triassic and Triassic-Jurassic boundary events show significant size decreases because of similar forcing mechanisms driven by rapid global warming.

  11. Review of rare earth element concentrations in oil shales of the Eocene Green River Formation (United States)

    Birdwell, Justin E.


    Concentrations of the lanthanide series or rare earth elements and yttrium were determined for lacustrine oil shale samples from the Eocene Green River Formation in the Piceance Basin of Colorado and the Uinta Basin of Utah. Unprocessed oil shale, post-pyrolysis (spent) shale, and leached shale samples were examined to determine if oil-shale processing to generate oil or the remediation of retorted shale affects rare earth element concentrations. Results for unprocessed Green River oil shale samples were compared to data published in the literature on reference materials, such as chondritic meteorites, the North American shale composite, marine oil shale samples from two sites in northern Tibet, and mined rare earth element ores from the United States and China. The Green River oil shales had lower rare earth element concentrations (66.3 to 141.3 micrograms per gram, μg g-1) than are typical of material in the upper crust (approximately 170 μg g-1) and were also lower in rare earth elements relative to the North American shale composite (approximately 165 μg g-1). Adjusting for dilution of rare earth elements by organic matter does not account for the total difference between the oil shales and other crustal rocks. Europium anomalies for Green River oil shales from the Piceance Basin were slightly lower than those reported for the North American shale composite and upper crust. When compared to ores currently mined for rare earth elements, the concentrations in Green River oil shales are several orders of magnitude lower. Retorting Green River oil shales led to a slight enrichment of rare earth elements due to removal of organic matter. When concentrations in spent and leached samples were normalized to an original rock basis, concentrations were comparable to those of the raw shale, indicating that rare earth elements are conserved in processed oil shales.

  12. Osteology of Icadyptes salasi, a giant penguin from the Eocene of Peru. (United States)

    Ksepka, Daniel T; Clarke, Julia A; DeVries, Thomas J; Urbina, Mario


    We present the first detailed description of the giant Eocene penguin Icadyptes salasi. The species is characterized by a narrow skull with a hyper-elongate spear-like beak, a robust cervical column and a powerful flipper. The bony beak tip of Icadyptes is formed by fusion of several elements and is unique among penguins, differing markedly from previously described giant penguin beaks. Vascular canal patterning similar to that of boobies, frigatebirds and albatrosses suggests I. salasi may have had a thin, sheet-like rhamphotheca unlike the thick rugose rhamphotheca of modern penguins. Together, these features suggest a novel ecology for I. salasi, most likely involving the capture of larger prey items via spearing. As the first described giant penguin specimen to preserve a complete wing skeleton, the I. salasi holotype yields significant insight into the shape, proportions and orientation of the wing in giant penguins. In articulation, the forelimb of I. salasi is straighter, permitting less manus and antibrachium flexion, than previous depictions of giant penguin wings. Cross-sections of the humerus and ulna reveal a level of osteosclerosis equalling or surpassing that of extant penguins. Based on ontogenetic data from extant penguins and the morphology of the carpometacarpus of I. salasi, we infer the retention of a free alular phalanx in basal penguins. Previously, the status of this element in penguins was disputed. Differences in the proportions of the manual phalanges contribute to a more abruptly tapering wingtip in I. salasi compared with crown penguins. Fossils from Peru, including the I. salasi holotype specimen, document that penguins expanded to nearly the whole of their extant latitudinal range early in their evolutionary history and during one of the warmest intervals in the Cenozoic.

  13. The Andean-type Gangdese Mountains: Paleoelevation record from the Paleocene-Eocene Linzhou Basin (United States)

    Ding, Lin; Xu, Qiang; Yue, Yahui; Wang, Houqi; Cai, Fulong; Li, Shun


    Paleoelevation reconstruction using oxygen isotopes is making a significant contribution to understanding the Cenozoic uplift of the Himalayas and the Tibetan Plateau. This paper presents new oxygen and carbon isotopic compositions from well dated Tertiary paleosols, lacustrine calcareous carbonates, and marls from the Nianbo (60-54 Ma) and upper Pana Formations (51-48 Ma) of the Linzizong Group in the Linzhou (Penbo) Basin. The sediments of the Nianbo Formation, which are >180 m-thick, were deposited in alluvial fans, braided rivers, fan deltas, and on nearshore to offshore lacustrine settings, whereas those of the upper Pana Formation are >100 m-thick and are comprised predominantly of proximal alluvial fan and braided river deposits. Correlations between the lithofacies and stable isotopic compositions suggest that the basin was mainly a hydrologically open environment. It is confirmed that the δ18Oc and δ13Cc values from Nianbo and Pana Formations have not yet been reset by late-stage diagenesis based on petrographic examination, oxygen isotope of the fossil ostracodes, and tectonic deformation of strata. The paleoelevations are reconstructed using the corrected most negative paleosurface water δ18Opsw values. These imply that the Linzhou area had attained an elevation of 4500±400 m during the period of the Indo-Asian collision, i.e., achieved a near-present elevation, and may form an Andean-type mountain range stretching the Gangdese arc before collision. The Gangdese Mountains probably maintained high elevations since at least the Paleocene and could play a crucial role in the climate change in the interior of the Tibetan Plateau during the Early Cenozoic. The paleogeomorphic scenario of the Eocene Tibet is proposed to exist at two high mountains in excess of 4500 m that sandwiched a low elevation basin.

  14. Transient dwarfism of soil fauna during the Paleocene–Eocene Thermal Maximum (United States)

    Smith, Jon J.; Hasiotis, Stephen T.; Kraus, Mary J.; Woody, Daniel T.


    Soil organisms, as recorded by trace fossils in paleosols of the Willwood Formation, Wyoming, show significant body-size reductions and increased abundances during the Paleocene–Eocene Thermal Maximum (PETM). Paleobotanical, paleopedologic, and oxygen isotope studies indicate high temperatures during the PETM and sharp declines in precipitation compared with late Paleocene estimates. Insect and oligochaete burrows increase in abundance during the PETM, suggesting longer periods of soil development and improved drainage conditions. Crayfish burrows and molluscan body fossils, abundant below and above the PETM interval, are significantly less abundant during the PETM, likely because of drier floodplain conditions and lower water tables. Burrow diameters of the most abundant ichnofossils are 30–46% smaller within the PETM interval. As burrow size is a proxy for body size, significant reductions in burrow diameter suggest that their tracemakers were smaller bodied. Smaller body sizes may have resulted from higher subsurface temperatures, lower soil moisture conditions, or nutritionally deficient vegetation in the high-CO2 atmosphere inferred for the PETM. Smaller soil fauna co-occur with dwarf mammal taxa during the PETM; thus, a common forcing mechanism may have selected for small size in both above- and below-ground terrestrial communities. We predict that soil fauna have already shown reductions in size over the last 150 years of increased atmospheric CO2 and surface temperatures or that they will exhibit this pattern over the next century. We retrodict also that soil fauna across the Permian-Triassic and Triassic-Jurassic boundary events show significant size decreases because of similar forcing mechanisms driven by rapid global warming. PMID:19805060

  15. Paleo-redox Reconstructions Across the Paleocene-Eocene Thermal Maximum (United States)

    Chun, C. O.; Delaney, M. L.; Zachos, J. C.


    Manganese and Uranium enrichment factors (EF) relative to crustal averages from nine Deep Sea Drilling Project and Ocean Drilling Program sites are presented to examine paleo-redox changes across the Paleocene-Eocene Thermal Maximum (PETM). We use geochemical tracers to infer the bottom-water oxygen concentrations during this abrupt warming event. Determining redox changes will test the hypothesis that low oxygen concentrations caused the benthic foraminifera extinction event as well as contribute to our understanding of where the source of isotopically light carbon was released. The comparison of Mn EF before and after a reductive cleaning procedure allows us to determine the presence of Mn-oxides or Mn-carbonates. Mn EF representing Mn oxides and no U EF suggest oxygenated bottom-waters. Mn-carbonates and U EF suggest reducing conditions and an early diagenetic phase. We will present our results relative to the orbitally tuned age model of Site 1263. Mn EF range from 1-9 in Atlantic sites, 1-35 Southern Ocean sites, and 5-400 in Pacific sites. U EF range from 1-5 in Atlantic sites, 1-90 in Southern Ocean sites, and crustal averages EF =1 in Pacific sites. Our initial results indicate reducing conditions prior, during, and in the recovery of the PETM at intermediate depth sites in the Atlantic and Southern Ocean while the Pacific sites remain oxygenated. Reducing bottom- water conditions in the Atlantic and Southern Ocean may have contributed to the benthic foraminifera extinction event. Release of methane in the oceans oxidizes to carbon dioxide, depleting bottom-water oxygen concentrations. Because our sites in the Atlantic have the most reducing bottom-waters, we suggest the Atlantic Ocean could have been the source for isotopically light carbon release during the PETM.

  16. Coupled hydrology and biogeochemistry of Paleocene–Eocene coal beds, northern Gulf of Mexico (United States)

    McIntosh, Jennifer C.; Warwick, Peter D.; Martini, Anna M.; Osborn, Stephen G.


    Thirty-six formation waters, gas, and microbial samples were collected and analyzed from natural gas and oil wells producing from the Paleocene to Eocene Wilcox Group coal beds and adjacent sandstones in north-central Louisiana, USA, to investigate the role hydrology plays on the generation and distribution of microbial methane. Major ion chemistry and Cl−Br relations of Wilcox Group formation waters suggest mixing of freshwater with halite-derived brines. High alkalinities (up to 47.8 meq/L), no detectable SO4, and elevated δ13C values of dissolved inorganic carbon (up to 20.5‰ Vienna Peedee belemnite [VPDB]) and CO2 (up to 17.67‰ VPDB) in the Wilcox Group coals and adjacent sandstones indicate the dominance of microbial methanogenesis. The δ13C and δD values of CH4, and carbon isotope fractionation of CO2 and CH4, suggest CO2 reduction is the major methanogenic pathway. Geochemical indicators for methanogenesis drop off significantly at chloride concentrations above ∼1.7 mol/L, suggesting that high salinities inhibit microbial activity at depths greater than ∼1.6 km. Formation waters in the Wilcox Group contain up to 1.6% modern carbon (A14C) to at least 1690 m depth; the covariance of δD values of co-produced H2O and CH4 indicate that the microbial methane was generated in situ with these Late Pleistocene or younger waters. The most enriched carbon isotope values for dissolved inorganic carbon (DIC) and CO2, and highest alkalinities, were detected in Wilcox Group sandstone reservoirs that were CO2 flooded in the 1980s for enhanced oil recovery, leading to the intriguing hypothesis that CO2 sequestration may actually enhance methanogenesis in organic-rich formations.

  17. Uranium favorability of late Eocene through Pliocene rocks of the South Texas Coastal Plain

    Energy Technology Data Exchange (ETDEWEB)

    Quick, J.V.; Thomas, N.G.; Brogdon, L.D.; Jones, C.A.; Martin, T.S.


    The results of a subsurface uranium favorability study of Tertiary rocks (late Eocene through Pliocene) in the Coastal Plain of South Texas are given. In ascending order, these rock units include the Yegua Formation, Jackson Group, Frio Clay, Catahoula Tuff, Oakville Sandstone, and Goliad Sand. The Vicksburg Group, Anahuac Formation, and Fleming Formation were not considered because they have unfavorable lithologies. The Yegua Formation, Jackson Group, Frio Clay, Catahoula Tuff, Oakville Sandstone, and Goliad Sand contain sandstones that may be favorable uranium hosts under certain environmental and structural conditions. All except the Yegua are known to contain ore-grade uranium deposits. Yegua and Jackson sandstones are found in strand plain-barrier bar systems that are aligned parallel to depositional and structural strike. These sands grade into shelf muds on the east, and lagoonal sediments updip toward the west. The lagoonal sediments in the Jackson are interrupted by dip-aligned fluvial systems. In both units, favorable areas are found in the lagoonal sands and in sands on the updip side of the strand-plain system. Favorable areas are also found along the margins of fluvial systems in the Jackson. The Frio and Catahoula consist of extensive alluvial-plain deposits. Favorable areas for uranium deposits are found along the margins of the paleo-channels where favorable structural features and numerous optimum sands are present. The Oakville and Goliad Formations consist of extensive continental deposits of fluvial sandstones. In large areas, these fluvial sandstones are multistoried channel sandstones that form very thick sandstone sequences. Favorable areas are found along the margins of the channel sequences. In the Goliad, favorable areas are also found on the updip margin of strand-plain sandstones where there are several sandstones of optimum thickness.

  18. Uranium favorability of late Eocene through Pliocene rocks of the South Texas Coastal Plain

    International Nuclear Information System (INIS)

    Quick, J.V.; Thomas, N.G.; Brogdon, L.D.; Jones, C.A.; Martin, T.S.


    The results of a subsurface uranium favorability study of Tertiary rocks (late Eocene through Pliocene) in the Coastal Plain of South Texas are given. In ascending order, these rock units include the Yegua Formation, Jackson Group, Frio Clay, Catahoula Tuff, Oakville Sandstone, and Goliad Sand. The Vicksburg Group, Anahuac Formation, and Fleming Formation were not considered because they have unfavorable lithologies. The Yegua Formation, Jackson Group, Frio Clay, Catahoula Tuff, Oakville Sandstone, and Goliad Sand contain sandstones that may be favorable uranium hosts under certain environmental and structural conditions. All except the Yegua are known to contain ore-grade uranium deposits. Yegua and Jackson sandstones are found in strand plain-barrier bar systems that are aligned parallel to depositional and structural strike. These sands grade into shelf muds on the east, and lagoonal sediments updip toward the west. The lagoonal sediments in the Jackson are interrupted by dip-aligned fluvial systems. In both units, favorable areas are found in the lagoonal sands and in sands on the updip side of the strand-plain system. Favorable areas are also found along the margins of fluvial systems in the Jackson. The Frio and Catahoula consist of extensive alluvial-plain deposits. Favorable areas for uranium deposits are found along the margins of the paleo-channels where favorable structural features and numerous optimum sands are present. The Oakville and Goliad Formations consist of extensive continental deposits of fluvial sandstones. In large areas, these fluvial sandstones are multistoried channel sandstones that form very thick sandstone sequences. Favorable areas are found along the margins of the channel sequences. In the Goliad, favorable areas are also found on the updip margin of strand-plain sandstones where there are several sandstones of optimum thickness

  19. Fire and ecosystem change in the Arctic across the Paleocene-Eocene Thermal Maximum (United States)

    Denis, E. H.; Pedentchouk, N.; Schouten, S.; Pagani, M.; Freeman, K. H.


    Fire, an important component of ecosystems at a range of spatial and temporal scales, affects vegetation distribution, the carbon cycle, and climate. In turn, climate influences fuel composition (e.g., amount and type of vegetation), fuel availability (e.g., vegetation that can burn based on precipitation and temperature), and ignition sources (e.g., lightning). Climate studies predict increased wildfire activity in future decades, but mechanisms that control the relationship between climate and fire are complex. Reconstructing environmental conditions during past warming events (e.g., the Paleocene-Eocene Thermal Maximum (PETM)) will help elucidate climate-vegetation-fire relationships that are expressed over long durations (1,000 - 10,000 yrs). The abrupt global warming during the PETM dramatically altered vegetation and hydrologic patterns, and, possibly, fire occurrence. To investigate coincident changes in climate, vegetation, and fire occurrence, we studied biomarkers, including polycyclic aromatic hydrocarbons (PAHs), terpenoids, and alkanes from the PETM interval at IODP site 302 (the Lomonosov Ridge) in the Arctic Ocean. Both pollen and biomarker records indicate angiosperms abundance increased during the PETM relative to gymnosperms, reflecting a significant ecological shift to angiosperm-dominated vegetation. PAH abundances increased relative to plant biomarkers throughout the PETM, which suggests PAH production increased relative to plant productivity. Increased PAH production associated with the angiosperm vegetation shift indicates a greater prevalence of more fire-prone species. A time lag between increased moisture transport (based on published δD of n-alkanes data) to the Arctic and increased angiosperms and PAH production suggests wetter conditions, followed by increased air temperatures, favored angiosperms and combined to enhance fire occurrence.

  20. Fluvial response to abrupt global warming at the Palaeocene/Eocene boundary. (United States)

    Foreman, Brady Z; Heller, Paul L; Clementz, Mark T


    Climate strongly affects the production of sediment from mountain catchments as well as its transport and deposition within adjacent sedimentary basins. However, identifying climatic influences on basin stratigraphy is complicated by nonlinearities, feedback loops, lag times, buffering and convergence among processes within the sediment routeing system. The Palaeocene/Eocene thermal maximum (PETM) arguably represents the most abrupt and dramatic instance of global warming in the Cenozoic era and has been proposed to be a geologic analogue for anthropogenic climate change. Here we evaluate the fluvial response in western Colorado to the PETM. Concomitant with the carbon isotope excursion marking the PETM we document a basin-wide shift to thick, multistoried, sheets of sandstone characterized by variable channel dimensions, dominance of upper flow regime sedimentary structures, and prevalent crevasse splay deposits. This progradation of coarse-grained lithofacies matches model predictions for rapid increases in sediment flux and discharge, instigated by regional vegetation overturn and enhanced monsoon precipitation. Yet the change in fluvial deposition persisted long after the approximately 200,000-year-long PETM with its increased carbon dioxide levels in the atmosphere, emphasizing the strong role the protracted transmission of catchment responses to distant depositional systems has in constructing large-scale basin stratigraphy. Our results, combined with evidence for increased dissolved loads and terrestrial clay export to world oceans, indicate that the transient hyper-greenhouse climate of the PETM may represent a major geomorphic 'system-clearing event', involving a global mobilization of dissolved and solid sediment loads on Earth's surface.

  1. Evidence of late Palaeocene-early Eocene equatorial rain forest refugia in southern Western Ghats, India. (United States)

    Prasad, V; Farooqui, A; Tripathi, S K M; Garg, R; Thakur, B


    Equatorial rain forests that maintain a balance between speciation and extinction are hot-spots for studies of biodiversity. Western Ghats in southern India have gained attention due to high tropical biodiversity and endemism in their southern most area. We attempted to track the affinities of the pollen fl ora of the endemic plants of Western Ghat area within the fossil palynoflora of late Palaeocene-early Eocene (approximately 55-50 Ma) sedimentary deposits of western and northeastern Indian region. The study shows striking similarity of extant pollen with twenty eight most common fossil pollen taxa of the early Palaeogene. Widespread occurrences of coal and lignite deposits during early Palaeogene provide evidence of existence of well diversified rain forest community and swampy vegetation in the coastal low lying areas all along the western and northeastern margins of the Indian subcontinent. Prevalence of excessive humid climate during this period has been seen as a result of equatorial positioning of Indian subcontinent, superimposed by a long term global warming phase (PETM and EECO) during the early Palaeogene. The study presents clear evidence that highly diversifi ed equatorial rain forest vegetation once widespread in the Indian subcontinent during early Palaeogene times, are now restricted in a small area as a refugia in the southernmost part of the Western Ghat area. High precipitation and shorter periods of dry months seem to have provided suitable environment to sustain lineages of ancient tropical vegetation in this area of Western Ghats in spite of dramatic climatic changes subsequent to the post India-Asia collision and during the Quaternary and Recent times.

  2. Nonhuman gamblers: lessons from rodents, primates, and robots

    Directory of Open Access Journals (Sweden)

    Fabio ePaglieri


    Full Text Available The search for neuronal and psychological underpinnings of pathological gambling in humans would benefit from investigating related phenomena also outside of our species. In this paper, we present a survey of studies in three widely different populations of agents, namely rodents, non-human primates, and robots. Each of these populations offer valuable and complementary insights on the topic, as the literature demonstrates. In addition, we highlight the deep and complex connections between relevant results across these different areas of research (i.e., cognitive and computational neuroscience, neuroethology, cognitive primatology, neuropsychiatry, evolutionary robotics, to make the case for a greater degree of methodological integration in future studies on pathological gambling.

  3. Mosaic Evolution of Brainstem Motor Nuclei in Catarrhine Primates

    Directory of Open Access Journals (Sweden)

    Seth D. Dobson


    Full Text Available Facial motor nucleus volume coevolves with both social group size and primary visual cortex volume in catarrhine primates as part of a specialized neuroethological system for communication using facial expressions. Here, we examine whether facial nucleus volume also coevolves with functionally unrelated brainstem motor nuclei (trigeminal motor and hypoglossal due to developmental constraints. Using phylogenetically informed multiple regression analyses of previously published brain component data, we demonstrate that facial nucleus volume is not correlated with the volume of other motor nuclei after controlling for medulla volume. Our results show that brainstem motor nuclei can evolve independently of other developmentally linked structures in association with specific behavioral ecological conditions. This finding provides additional support for the mosaic view of brain evolution.

  4. A perceptual pitch boundary in a non-human primate

    Directory of Open Access Journals (Sweden)

    Olivier eJoly


    Full Text Available Pitch is an auditory percept critical to the perception of music and speech, and for these harmonic sounds, pitch is closely related to the repetition rate of the acoustic wave. This paper reports a test of the assumption that non-human primates and especially rhesus monkeys perceive the pitch of these harmonic sounds much as humans do. A new procedure was developed to train macaques to discriminate the pitch of harmonic sounds and thereby demonstrate that the lower limit for pitch perception in macaques is close to 30 Hz, as it is in humans. Moreover, when the phases of successive harmonics are alternated to cause a pseudo-doubling of the repetition rate, the lower pitch boundary in macaques decreases substantially, as it does in humans. The results suggest that both species use neural firing times to discriminate pitch, at least for sounds with relatively low repetition rates.

  5. Comparative primate neuroimaging: insights into human brain evolution. (United States)

    Rilling, James K


    Comparative neuroimaging can identify unique features of the human brain and teach us about human brain evolution. Comparisons with chimpanzees, our closest living primate relative, are critical in this endeavor. Structural magnetic resonance imaging (MRI) has been used to compare brain size development, brain structure proportions and brain aging. Positron emission tomography (PET) imaging has been used to compare resting brain glucose metabolism. Functional MRI (fMRI) has been used to compare auditory and visual system pathways, as well as resting-state networks of connectivity. Finally, diffusion-weighted imaging (DWI) has been used to compare structural connectivity. Collectively, these methods have revealed human brain specializations with respect to development, cortical organization, connectivity, and aging. These findings inform our knowledge of the evolutionary changes responsible for the special features of the modern human mind.

  6. The multisensory roles for auditory cortex in primate vocal communication. (United States)

    Ghazanfar, Asif A


    Primate vocal communication is a fundamentally multisensory behavior and this will be reflected in the different roles brain regions play in mediating it. Auditory cortex is illustrative, being influenced, I will argue, by the visual, somatosensory, proprioceptive and motor modalities during vocal communication. It is my intention that the data reviewed here suggest that investigating auditory cortex through the lens of a specific behavior may lead to a much clearer picture of its functions and dynamic organization. One possibility is that, beyond its tonotopic and cytoarchitectural organization, the auditory cortex may be organized according to ethologically-relevant actions. Such action-specific representations would be overlayed on top of traditional mapping schemes and would help mediate motor and multisensory processes related to a particular type of behavior.

  7. Pain Relief in Nonhuman Primate Models of Arthritis. (United States)

    Vierboom, Michel P M; Breedveld, Elia; Keehnen, Merei; Klomp, Rianne; Bakker, Jaco


    Animal models of rheumatoid arthritis are important in the elucidation of etiopathogenic mechanisms of the disease and for the development of promising new therapies. Species specificity of new biological compounds and their mode of action preclude safety and efficacy testing in rodent models of disease. Nonhuman primates (NHP) can fill this niche and provide the only relevant model. Over the last two decades models of collagen-induced arthritis (CIA) were developed in the rhesus monkey and the common marmoset. However, NHP are higher-order animals and complex sentient beings. So especially in models where pain is an intricate part of the disease, analgesia needs to be addressed because of ethical considerations. In our model, a morphine-based pain relief was used that does not interfere with the normal development of disease allowing us to evaluate important mechanistic aspects of the arthritis.

  8. Immunology studies in non-human primate models of tuberculosis. (United States)

    Flynn, JoAnne L; Gideon, Hannah P; Mattila, Joshua T; Lin, Philana Ling


    Non-human primates, primarily macaques, have been used to study tuberculosis for decades. However, in the last 15 years, this model has been refined substantially to allow careful investigations of the immune response and host-pathogen interactions in Mycobacterium tuberculosis infection. Low-dose challenge with fully virulent strains in cynomolgus macaques result in the full clinical spectrum seen in humans, including latent and active infection. Reagents from humans are usually cross-reactive with macaques, further facilitating the use of this model system to study tuberculosis. Finally, macaques develop the spectrum of granuloma types seen in humans, providing a unique opportunity to investigate bacterial and host factors at the local (lung and lymph node) level. Here, we review the past decade of immunology and pathology studies in macaque models of tuberculosis. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  9. Cocaine is pharmacologically active in the nonhuman primate fetal brain

    DEFF Research Database (Denmark)

    Benveniste, Helene; Fowler, Joanna S; Rooney, William D


    -trimester pregnant nonhuman primates, cocaine at doses typically used by drug abusers significantly increased brain glucose metabolism to the same extent in the mother as in the fetus (approximately 100%). Inasmuch as brain glucose metabolism is a sensitive marker of brain function, the current findings provide...... evidence that cocaine use by a pregnant mother will also affect the function of the fetal brain. We are also unique in showing that cocaine's effects in brain glucose metabolism differed in pregnant (increased) and nonpregnant (decreased) animals, which suggests that the psychoactive effects of cocaine...... are influenced by the state of pregnancy. Our findings have clinical implications because they imply that the adverse effects of prenatal cocaine exposure to the newborn child include not only cocaine's deleterious effects to the placental circulation, but also cocaine's direct pharmacological effect...

  10. Primates--a natural heritage of conflict resolution. (United States)

    de Waal, F B


    The traditional notion of aggression as an antisocial instinct is being replaced by a framework that considers it a tool of competition and negotiation. When survival depends on mutual assistance, the expression of aggression is constrained by the need to maintain beneficial relationships. Moreover, evolution has produced ways of countering its disruptive consequences. For example, chimpanzees kiss and embrace after fights, and other nonhuman primates engage in similar "reconciliations." Theoretical developments in this field carry implications for human aggression research. From families to high schools, aggressive conflict is subject to the same constraints known of cooperative animal societies. It is only when social relationships are valued that one can expect the full complement of natural checks and balances.

  11. Primate conservation: integrating communities through environmental education programs. (United States)

    Padua, Suzana M


    Environmental education has evolved over the years to respond to the varied complexities found in the different localities where it is practiced. In many parts of the world where biodiversity is rich, social conditions are poor, so educators have included sustainable development alternatives to better the environment and the livelihoods of local communities. Primate conservation education programs, which are often based in areas that face such challenges, have been a vanguard in creating means to integrate people with their natural environment and thus conquer supporters for the protection of natural habitats. In the search for effectiveness they have adopted evaluation methods to help assess what was offered. An example from Brazil is described in this commentary. (c) 2009 Wiley-Liss, Inc.

  12. DNA synthesis and cell division in the adult primate brain

    International Nuclear Information System (INIS)

    Rakic, P.


    It is generally accepted that the adult human brain is incapable of producing new neuron. Even cursory examination of neurologic, neuropathologic, or neurobiological textbooks published during the past 50 years will testify that this belief is deeply entrenched. In his classification of cell populations on the basis of their proliferative behavior, Leblond regarded neurons of the central nervous system as belonging to a category of static, nonrenewing epithelial tissue incapable of expanding or replenishing itself. This belief, however needs to re reexamined for two major reasons: First, as reviewed below, a number of reports have provided evidence of neurogenesis in adult brain of several vertebrate species. Second, the capacity for neurogenesis in the adult primate central nervous system has never been examined by modern methods. In this article the author described recent results from an extensive autoradiographic analysis performed on twelve rhesus monkeys injected with the specific DNA precursor [ 3 H] thymidine at ages ranging from 6 postnatal months to 17 years

  13. An overview of nonhuman primates in aging research. (United States)

    Mattison, Julie A; Vaughan, Kelli L


    A graying human population and the rising costs of healthcare have fueled the growing need for a sophisticated translational model of aging. Nonhuman primates (NHPs) experience aging processes similar to humans and, as a result, provide an excellent opportunity to study a closely related species. Rhesus monkeys share >92% homology and are the most commonly studied NHP. However, their substantial size, long lifespan, and the associated expense are prohibitive factors. Marmosets are rapidly becoming the preferred NHP for biomedical testing due to their small size, low zoonotic risk, reproductive efficiency, and relatively low-cost. Both species experience age-related pathology similar to humans, such as cancer, diabetes, arthritis, cardiovascular disease, and neurological decline. As a result, their use in aging research is paving the way to improved human health through a better understanding of the mechanisms of aging. Published by Elsevier Inc.

  14. Looking forward to a PET scanner designed for non-human primates

    International Nuclear Information System (INIS)

    Tanaka, Keiji


    The cerebral cortex of non-human primates has been divided, mainly by anatomical techniques, into an enormous number of areas. We are looking forward to a PET scanner designed for non-human primates, with a hope to determine active brain regions when the animal does various cognitive tasks. This measurement with PET can be combined with single cell recordings and anatomical tracer studies in non-human primates. Another big hope is to detect a change of active regions as the learning advances. (author)

  15. Application of the genome editing tool CRISPR/Cas9 in non-human primates. (United States)

    Luo, Xin; Li, Min; Su, Bing


    In the past three years, RNA-guided Cas9 nuclease from the microbial clustered regularly interspaced short palindromic repeats (CRISPR) adaptive immune system has been used to facilitate efficient genome editing in many model and non-model animals. However, its application in nonhuman primates is still at the early stage, though in view of the similarities in anatomy, physiology, behavior and genetics, closely related nonhuman primates serve as optimal models for human biology and disease studies. In this review, we summarize the current proceedings of gene editing using CRISPR/Cas9 in nonhuman primates.

  16. A Non-Human Primate Model of Severe Pneumococcal Pneumonia (United States)

    Reyes, Luis F.; Restrepo, Marcos I.; Hinojosa, Cecilia A.; Soni, Nilam J.; Shenoy, Anukul T.; Gilley, Ryan P.; Gonzalez-Juarbe, Norberto; Noda, Julio R.; Winter, Vicki T.; de la Garza, Melissa A.; Shade, Robert E.; Coalson, Jacqueline J.; Giavedoni, Luis D.; Anzueto, Antonio; Orihuela, Carlos J.


    Rationale Streptococcus pneumoniae is the leading cause of community-acquired pneumonia and infectious death in adults worldwide. A non-human primate model is needed to study the molecular mechanisms that underlie the development of severe pneumonia, identify diagnostic tools, explore potential therapeutic targets, and test clinical interventions during pneumococcal pneumonia. Objective To develop a non-human primate model of pneumococcal pneumonia. Methods Seven adult baboons (Papio cynocephalus) were surgically tethered to a continuous monitoring system that recorded heart rate, temperature, and electrocardiography. Animals were inoculated with 109 colony-forming units of S. pneumoniae using bronchoscopy. Three baboons were rescued with intravenous ampicillin therapy. Pneumonia was diagnosed using lung ultrasonography and ex vivo confirmation by histopathology and immunodetection of pneumococcal capsule. Organ failure, using serum biomarkers and quantification of bacteremia, was assessed daily. Results Challenged animals developed signs and symptoms of pneumonia 4 days after infection. Infection was characterized by the presence of cough, tachypnea, dyspnea, tachycardia and fever. All animals developed leukocytosis and bacteremia 24 hours after infection. A severe inflammatory reaction was detected by elevation of serum cytokines, including Interleukin (IL)1Ra, IL-6, and IL-8, after infection. Lung ultrasonography precisely detected the lobes with pneumonia that were later confirmed by pathological analysis. Lung pathology positively correlated with disease severity. Antimicrobial therapy rapidly reversed symptomology and reduced serum cytokines. Conclusions We have developed a novel animal model for severe pneumococcal pneumonia that mimics the clinical presentation, inflammatory response, and infection kinetics seen in humans. This is a novel model to test vaccines and treatments, measure biomarkers to diagnose pneumonia, and predict outcomes. PMID:27855182

  17. High reinforcing efficacy of nicotine in non-human primates.

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    Bernard Le Foll

    Full Text Available Although tobacco appears highly addictive in humans, there has been persistent controversy about the ability of its psychoactive ingredient nicotine to induce self-administration behavior in laboratory animals, bringing into question nicotine's role in reinforcing tobacco smoking. Because of ethical difficulties in inducing nicotine dependence in naïve human subjects, we explored reinforcing effects of nicotine in experimentally-naive non-human primates given access to nicotine for periods of time up to two years. Five squirrel monkeys with no experimental history were allowed to intravenously self-administer nicotine by pressing one of two levers. The number of presses on the active lever needed to obtain each injection was fixed (fixed-ratio schedule or increased progressively with successive injections during the session (progressive-ratio schedule, allowing evaluation of both reinforcing and motivational effects of nicotine under conditions of increasing response cost. Over time, a progressive shift toward high rates of responding on the active lever, but not the inactive lever, developed. The monkeys' behavior was clearly directed toward nicotine self-administration, rather than presentation of environmental stimuli associated with nicotine injection. Both schedules of reinforcement revealed a high motivation to self-administer nicotine, with monkeys continuing to press the lever when up to 600 lever-presses were needed for each injection of nicotine. Thus, nicotine, by itself, in the absence of behavioral or drug-exposure history, is a robust and highly effective reinforcer of drug-taking behavior in a non-human primate model predictive of human behavior. This supports the use of nicotinic ligands for the treatment of smokers, and this novel preclinical model offers opportunities to test future medications for the treatment of nicotine dependence.

  18. Irrational choice behavior in human and nonhuman primates. (United States)

    Perdue, Bonnie M; Brown, Ella R


    Choice behavior in humans has motivated a large body of research with a focus on whether decisions can be considered to be rational. In general, humans prefer having choice, as do a number of other species that have been tested, even though having increased choice does not necessarily yield a positive outcome. Humans have been found to choose an option more often only because the opportunity to select it was diminishing, an example of a deviation from economic rationality. Here we extend this paradigm to nonhuman primates in an effort to understand the mechanisms underlying this finding. In this study, we presented two groups of laboratory monkeys, capuchins (Cebus apella) and rhesus macaques (Macaca mulatta), as well as human subjects, with a computerized task in which subjects were presented with two differently colored icons. When the subject selected an icon, differing numbers of food pellets were dispensed (or points were assigned), making each icon correspond to a certain level of risk (one icon yielded 1 or 4 pellets/points and the other yielded 2 or 3). Initially, both options remained constantly available and we established choice preference scores for each subject. Then, we assessed preference patterns once the options were not continuously available. Specifically, choosing one icon would cause the other to shrink in size on the screen and eventually disappear if never selected. Selecting it would restore it to its full size. As predicted, humans shifted their risk preferences in the diminishing options phase, choosing to click on both icons more equally in order to keep both options available. At the group level, capuchin monkeys showed this pattern as well, but there was a great deal of individual variability in both capuchins and macaques. The present work suggests that there is some degree of continuity between human and nonhuman primates in the desire to have choice simply for the sake of having choice.

  19. Gonadectomy Negatively Impacts Social Behavior of Adolescent Male Primates (United States)

    Richards, A. Brent; Morris, Richard W.; Ward, Sarah; Schmitz, Stephanie; Rothmond, Debora A.; Noble, Pam L.; Woodward, Ruth A.; Winslow, James T.; Weickert, Cynthia Shannon


    Social behavior changes dramatically during primate adolescence. However, the extent to which testosterone and other gonadal hormones are necessary for adolescent social behavioral development is unknown. In this study, we determined that gonadectomy significantly impairs social dominance in naturalistic settings and changes reactions to social stimuli in experimental settings. Rhesus macaques were castrated (n = 6) or sham operated (n = 6) at age 2.4 years, group-housed for 2 years, and ethograms were collected weekly. During adolescence the gonadally intact monkeys displayed a decrease in subordinate behaviors and an increase in dominant behaviors, which ultimately related to a rise in social status and rank in the dominance hierarchy. We measured monkey’s reactions to emotional faces (fear, threat, neutral) of conspecifics of three ages (adult, peer, infant). Intact monkeys were faster to retrieve a treat in front of a threatening or infant face, while castrated monkeys did not show a differential response to different emotional faces or ages. No group difference in reaction to an innate fear-eliciting object (snake) was found. Approach and proximity responses to familiar versus unfamiliar conspecifics were tested, and intact monkeys spent more time proximal to a novel conspecific as compared to castrates who tended to spend more time with a familiar conspecific. No group differences in time spent with novel or familiar objects were found. Thus, gonadectomy resulted in the emergence of significantly different responses to social stimuli, but not non-social stimuli. Our work suggests that intact gonads, which are needed to produce adolescent increases in circulating testosterone, impact social behavior during adolescences in primates. PMID:19361511

  20. Primate cathelicidin orthologues display different structures and membrane interactions. (United States)

    Morgera, Francesca; Vaccari, Lisa; Antcheva, Nikolinka; Scaini, Denis; Pacor, Sabrina; Tossi, Alessandro


    The human cathelicidin LL-37 displays both direct antibacterial activities and the capacity to modulate host-cell activities. These depend on structural characteristics that are subject to positive selection for variation, as observed in a previous analysis of the CAMP gene (encoding LL-37) in primates. The altered balance between cationic and anionic residues in different primate orthologues affects intramolecular salt-bridging and influences the stability of the helical conformation and tendency to aggregate in solution of the peptide. In the present study, we have analysed the effects of these structural variations on membrane interactions for human LL-37, rhesus RL-37 and orang-utan LL-37, using several complementary biophysical and biochemical methods. CD and ATR (attenuated total reflection)-FTIR (Fourier-transform IR) spectroscopy on model membranes indicate that RL-37, which is monomeric and unstructured in bulk solution [F-form (free form)], and human LL-37, which is partly structured and probably aggregated [A-form (aggregated form)], bind biological membranes in different manners. RL-37 may insert more deeply into the lipid bilayer than LL-37, which remains aggregated. AFM (atomic force microscopy) performed on the same supported bilayer as used for ATR-FTIR measurements suggests a carpet-like mode of permeabilization for RL37 and formation of more defined worm-holes for LL-37. Comparison of data from the biological activity on bacterial cells with permeabilization of model membranes indicates that the structure/aggregation state also affects the trajectory of the peptides from bulk solution through the outer cell-wall layers to the membrane. The results of the present study suggest that F-form cathelicidin orthologues may have evolved to have primarily a direct antimicrobial defensive capacity, whereas the A-forms have somewhat sacrificed this to gain host-cell modulating functions.

  1. Emergent patterns of social affiliation in primates, a model.

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    Ivan Puga-Gonzalez


    Full Text Available Many patterns of affiliative behaviour have been described for primates, for instance: reciprocation and exchange of grooming, grooming others of similar rank, reconciliation of fights, and preferential reconciliation with more valuable partners. For these patterns several functions and underlying cognitive processes have been suggested. It is, however, difficult to imagine how animals may combine these diverse considerations in their mind. Although the co-variation hypothesis, by limiting the social possibilities an individual has, constrains the number of cognitive considerations an individual has to take, it does not present an integrated theory of affiliative patterns either. In the present paper, after surveying patterns of affiliation in egalitarian and despotic macaques, we use an individual-based model with a high potential for self-organisation as a starting point for such an integrative approach. In our model, called GrooFiWorld, individuals group and, upon meeting each other, may perform a dominance interaction of which the outcomes of winning and losing are self-reinforcing. Besides, if individuals think they will be defeated, they consider grooming others. Here, the greater their anxiety is, the greater their "motivation" to groom others. Our model generates patterns similar to many affiliative patterns of empirical data. By merely increasing the intensity of aggression, affiliative patterns in the model change from those resembling egalitarian macaques to those resembling despotic ones. Our model produces such patterns without assuming in the mind of the individual the specific cognitive processes that are usually thought to underlie these patterns (such as recordkeeping of the acts given and received, a tendency to exchange, memory of the former fight, selective attraction to the former opponent, and estimation of the value of a relationship. Our model can be used as a null model to increase our understanding of affiliative

  2. Lacustrine 87Sr/86Sr as a tracer to reconstruct Milankovitch forcing of the Eocene hydrologic cycle (United States)

    Baddouh, M'bark; Meyers, Stephen R.; Carroll, Alan R.; Beard, Brian L.; Johnson, Clark M.


    The Green River Formation (GRF) provides one of the premier paleoclimate archives of the Early Eocene Climatic Optimum (∼50 Ma), representing the apex of the early Cenozoic greenhouse climate. Rhythmic lake-level variability expressed in the GRF has inspired numerous hypotheses for the behavior of the Eocene hydrologic cycle, including its linkage to astronomical forcing, solar variability, and the El Niño Southern Oscillation (ENSO). However, the lack of sufficient proxy data to document atmospheric water-mass transport and the geographic pattern of evaporation/precipitation/runoff has made it difficult to discriminate between different models for astronomical forcing. Variable 87Sr/86Sr ratios of bedrock that encompass the GRF provide an opportunity to reconstruct the spatial expression of the Eocene hydrologic cycle and its linkage to lake level. Here Sr isotope data from the Wilkins Peak Member, a rhythmic succession that has been demonstrated to record Milankovitch forcing of lake levels, indicate that high lake levels reflect an increased proportion of runoff from less radiogenic rocks west of the basin, eliminating a number of the existing astronomical-forcing hypotheses. The 87Sr/86Sr variability is consistent with a change in mean ENSO state, which is predicted by climate models to be linked to orbital-insolation. Thus, the 87Sr/86Sr data reveal a coupling of high frequency (ENSO) and low frequency (astronomical) climate variability, and also predict the existence of sizable astronomically-forced alpine snowpack during the last greenhouse climate. More broadly, this study demonstrates the utility of 87Sr/86Sr as a powerful tool for reconstructing the deep-time hydrologic cycle.

  3. Apatite fission-track evidence of widespread Eocene heating and exhumation in the Yukon-Tanana Upland, interior Alaska (United States)

    Dusel-Bacon, C.; Murphy, J.M.


    We present an apatite fission-track (AFT) study of five plutonic rocks and seven metamorphic rocks across 310 km of the Yukon-Tanana Upland in east-central Alaska. Samples yielding ???40 Ma AFT ages and mean confined track lengths > 14 ??m with low standard deviations cooled rapidly from >120??C to 40 Ma suggest partial annealing and, therefore, lower maximum temperatures (???90-105??C). A few samples with single-grain ages of ???20 Ma apparently remained above ???50??C after initial cooling. Although the present geothermal gradient in the western Yukon-Tanana Upland is ???32??C/km, it could have been as high as 45??C/km during a widespread Eocene intraplate magmatic episode. Prior to rapid exhumation, samples with ???40 Ma AFT ages were >3.8-2.7 km deep and samples with >50 Ma AFT ages were >3.3-2.0 km deep. We calculate a 440-320 m/Ma minimum rate for exhumation of all samples during rapid cooling. Our AFT data, and data from rocks north of Fairbanks and from the Eielson deep test hole, indicate up to 3 km of post-40 Ma vertical displacement along known and inferred northeast-trending high-angle faults. The predominance of 40-50 Ma AFT ages throughout the Yukon-Tanana Upland indicates that, prior to the post-40 Ma relative uplift along some northeast-trending faults, rapid regional cooling and exhumation closely followed the Eocene extensional magmatism. We propose that Eocene magmatism and exhumation were somehow related to plate movements that produced regional-scale oroclinal rotation, northward translation of outboard terranes, major dextral strike-slip faulting, and subduction of an oceanic spreading ridge along the southern margin of Alaska.

  4. Planktic foraminiferal response to early Eocene carbon cycle perturbations in the southeast Atlantic Ocean (ODP Site 1263) (United States)

    Luciani, Valeria; D'Onofrio, Roberta; Dickens, Gerald R.; Wade, Bridget S.


    At low latitude locations in the northern hemisphere, striking changes in the relative abundances and diversity of the two dominant planktic foraminifera genera, Morozovella and Acarinina, are known to have occurred close to the Early Eocene Climatic Optimum (EECO; 49-53 Ma). Lower Eocene carbonate-rich sediments at Ocean Drilling Program (ODP) Site 1263 were deposited on a bathymetric high (Walvis Ridge) at 40° S, and afford an opportunity to examine such planktic foraminiferal assemblage changes in a temperate southern hemisphere setting. We present here quantified counts of early Eocene planktic foraminiferal assemblages from Hole 1263B, along with bulk sediment stable isotope analyses and proxy measurements for carbonate dissolution. The bulk sediment δ13C record at Site 1263 resembles similar records generated elsewhere, such that known and inferred hyperthermal events can be readily identified. Although some carbonate dissolution has occurred, the well-preserved planktic foraminiferal assemblages mostly represent primary changes in environmental conditions. Our results document the permanent decrease in Morozovella abundance and increase in Acarinina abundance at the beginning of the EECO, although this switch occurred 165 kyr after that at low-latitude northern hemisphere locations. This suggests that unfavourable environmental conditions for morozovellids at the start of the EECO, such as sustained passage of a temperature threshold or other changes in surface waters, occurred at lower latitudes first. The remarkable turnover from Morozovella to Acarinina was widely geographically widespread, although the causal mechanism remains elusive. In addition, at Site 1263, we document the virtual disappearance within the EECO of the biserial chiloguembelinids, commonly considered as inhabiting intermediate water depths, and a reduction in abundance of the thermocline-dwelling subbotinids. We interpret these changes as signals of subsurface water properties

  5. First bird remains from the Eocene of Algarrobo, central Chile Primeros restos de aves del Eoceno de Algarrobo, Chile central

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    Roberto E Yury-Yáñez


    Full Text Available Paleogene records of birds in the Eastern margin of the Pacific Ocean have increased in recent years, being almost exclusively restricted to fossil Sphenisciformes (penguins. New avian remains (Ornithurae, Neornithes from Middle-to-Late Eocene levels of the Estratos de Algarrobo unit, in Algarrobo, central Chile, are disclosed in the present work. These new finds are significant in representing the first non-spheniscid bird remains of Middle to Late Eocene age, recovered in mid-latitudes of the eastern Pacific and probably belonging to a procelarid. It complements the regional record of Eocene birds, previously known only at high-latitudes such as Seymour Island (Antarctica and Magallanes (Chile, and low-latitude locations in Peru.Los registros de aves paleógenas en el margen oriental del Océano Pacífico se han incrementado en los últimos años, estando casi exclusivamente restringidos a Sphenisciformes fósiles (pingüinos. Nuevos fósiles avianos (Ornithurae, Neornithes provenientes de niveles del Eoceno Medio a Tardío de los Estratos de Algarrobo, en Algarrobo, Chile central, son dados a conocer en el presente trabajo. Estos nuevos hallazgos son significativos en representar los primeros restos de aves no-spheníscidos de edad Eoceno Medio a Tardío, recuperadas en latitudes intermedias del Pacífico oriental y probablemente pertenezcan a un procelárido. Este hallazgo complementa el registro regional del grupo durante el Eoceno, anteriormente conocido en localidades de altas latitudes como isla Seymour (Antártica y Magallanes (Chile, y localidades de bajas latitudes en Perú.

  6. The Paleocene Eocene carbon isotope excursion in higher plant organic matter: Differential fractionation of angiosperms and conifers in the Arctic (United States)

    Schouten, Stefan; Woltering, Martijn; Rijpstra, W. Irene C.; Sluijs, Appy; Brinkhuis, Henk; Sinninghe Damsté, Jaap S.


    A study of upper Paleocene-lower Eocene (P-E) sediments deposited on the Lomonosov Ridge in the central Arctic Ocean reveals relatively high abundances of terrestrial biomarkers. These include dehydroabietane and simonellite derived from conifers (gymnosperms) and a tetra-aromatic triterpenoid derived from angiosperms. The relative percentage of the angiosperm biomarker of the summed angiosperm + conifer biomarkers was increased at the end of the Paleocene-Eocene thermal maximum (PETM), different when observed with pollen counts which showed a relative decrease in angiosperm pollen. Stable carbon isotopic analysis of these biomarkers shows that the negative carbon isotope excursion (CIE) during the PETM amounts to 3‰ for both conifer biomarkers, dehydroabietane and simonellite, comparable to the magnitude of the CIE inferred from marine carbonates, but significantly lower than the 4.5‰ of the terrestrial C 29n-alkane [M. Pagani, N. Pedentchouk, M. Huber, A. Sluijs, S. Schouten, H. Brinkhuis, J.S. Sinninghe Damsté, G.R. Dickens, and the IODP Expedition 302 Expedition Scientists (2006), Arctic's hydrology during global warming at the Paleocene-Eocene thermal maximum. Nature, 442, 671-675.], which is a compound sourced by both conifers and angiosperms. Conspicuously, the angiosperm-sourced aromatic triterpane shows a much larger CIE of 6‰ and suggests that angiosperms increased in their carbon isotopic fractionation during the PETM. Our results thus indicate that the 4.5‰ C 29n-alkane CIE reported previously represents the average CIE of conifers and angiosperms at this site and suggest that the large and variable CIE observed in terrestrial records may be partly explained by the variable contributions of conifers and angiosperms. The differential response in isotopic fractionation of angiosperms and conifers points to different physiological responses of these vegetation types to the rise in temperature, humidity, and greenhouse gases during the PETM.

  7. Eocene and Miocene extension, meteoric fluid infiltration, and core complex formation in the Great Basin (Raft River Mountains, Utah) (United States)

    Methner, Katharina; Mulch, Andreas; Teyssier, Christian; Wells, Michael L.; Cosca, Michael A.; Gottardi, Raphael; Gebelin, Aude; Chamberlain, C. Page


    Metamorphic core complexes (MCCs) in the North American Cordillera reflect the effects of lithospheric extension and contribute to crustal adjustments both during and after a protracted subduction history along the Pacific plate margin. While the Miocene-to-recent history of most MCCs in the Great Basin, including the Raft River-Albion-Grouse Creek MCC, is well documented, early Cenozoic tectonic fabrics are commonly severely overprinted. We present stable isotope, geochronological (40Ar/39Ar), and microstructural data from the Raft River detachment shear zone. Hydrogen isotope ratios of syntectonic white mica (δ2Hms) from mylonitic quartzite within the shear zone are very low (−90‰ to −154‰, Vienna SMOW) and result from multiphase synkinematic interaction with surface-derived fluids. 40Ar/39Ar geochronology reveals Eocene (re)crystallization of white mica with δ2Hms ≥ −154‰ in quartzite mylonite of the western segment of the detachment system. These δ2Hms values are distinctively lower than in localities farther east (δ2Hms ≥ −125‰), where 40Ar/39Ar geochronological data indicate Miocene (18–15 Ma) extensional shearing and mylonitic fabric formation. These data indicate that very low δ2H surface-derived fluids penetrated the brittle-ductile transition as early as the mid-Eocene during a first phase of exhumation along a detachment rooted to the east. In the eastern part of the core complex, prominent top-to-the-east ductile shearing, mid-Miocene 40Ar/39Ar ages, and higher δ2H values of recrystallized white mica, indicate Miocene structural and isotopic overprinting of Eocene fabrics.

  8. Synchronizing early Eocene deep-sea and continental records - cyclostratigraphic age models for the Bighorn Basin Coring Project drill cores (United States)

    Westerhold, Thomas; Röhl, Ursula; Wilkens, Roy H.; Gingerich, Philip D.; Clyde, William C.; Wing, Scott L.; Bowen, Gabriel J.; Kraus, Mary J.


    A consistent chronostratigraphic framework is required to understand the effect of major paleoclimate perturbations on both marine and terrestrial ecosystems. Transient global warming events in the early Eocene, at 56-54 Ma, show the impact of large-scale carbon input into the ocean-atmosphere system. Here we provide the first timescale synchronization of continental and marine deposits spanning the Paleocene-Eocene Thermal Maximum (PETM) and the interval just prior to the Eocene Thermal Maximum 2 (ETM-2). Cyclic variations in geochemical data come from continental drill cores of the Bighorn Basin Coring Project (BBCP, Wyoming, USA) and from marine deep-sea drilling deposits retrieved by the Ocean Drilling Program (ODP). Both are dominated by eccentricity-modulated precession cycles used to construct a common cyclostratigraphic framework. Integration of age models results in a revised astrochronology for the PETM in deep-sea records that is now generally consistent with independent 3He age models. The duration of the PETM is estimated at ˜ 200 kyr for the carbon isotope excursion and ˜ 120 kyr for the associated pelagic clay layer. A common terrestrial and marine age model shows a concurrent major change in marine and terrestrial biota ˜ 200 kyr before ETM-2. In the Bighorn Basin, the change is referred to as Biohorizon B and represents a period of significant mammalian turnover and immigration, separating the upper Haplomylus-Ectocion Range Zone from the Bunophorus Interval Zone and approximating the Wa-4-Wa-5 land mammal zone boundary. In sediments from ODP Site 1262 (Walvis Ridge), major changes in the biota at this time are documented by the radiation of a second generation of apical spine-bearing sphenolith species (e.g., S. radians and S. editus), the emergence of T. orthostylus, and the marked decline of D. multiradiatus.

  9. First comparative study of primate morphological and molecular evolutionary rates including muscle data: implications for the tempo and mode of primate and human evolution (United States)

    Diogo, Rui; Peng, Zuogang; Wood, Bernard


    Here we provide the first report about the rates of muscle evolution derived from Bayesian and parsimony cladistic analyses of primate higher-level phylogeny, and compare these rates with published rates of molecular evolution. It is commonly accepted that there is a ‘general molecular slow-down of hominoids’, but interestingly the rates of muscle evolution in the nodes leading and within the hominoid clade are higher than those in the vast majority of other primate clades. The rate of muscle evolution at the node leading to Homo (1.77) is higher than that at the nodes leading to Pan (0.89) and particularly to Gorilla (0.28). Notably, the rates of muscle evolution at the major euarchontan and primate nodes are different, but within each major primate clade (Strepsirrhini, Platyrrhini, Cercopithecidae and Hominoidea) the rates at the various nodes, and particularly at the nodes leading to the higher groups (i.e. including more than one genera), are strikingly similar. We explore the implications of these new data for the tempo and mode of primate and human evolution. PMID:23320764

  10. Africa was still far south in the Late Ypresian: Paleomagnetic study on the early Eocene 'Minia' formation in central Egypt (United States)

    Lotfy, H.; Heleika, M. Abu; Mostafa, R.; Wahbah, D.


    The paleomagnetic study was carried out on three sections of the Late Ypresian "Minia" formation limestone, in order to shed light on the paleolatitude of northeast Africa upon the end of the Early Eocene. The initial study on the anisotropy of magnetic susceptibility [AMS] helped in confining the paleomagnetic sampling to the virtually isotropic limestone beds. The subsequent stepwise thermal demagnetization of the three-axis isothermal remanence acquired in one sample of each sampled site, revealed the limited contribution of goethite and hematite with the main remanence carrier magnetite in most samples.

  11. Cretaceous-Eocene provenance connections between the Palawan Continental Terrane and the northern South China Sea margin (United States)

    Shao, Lei; Cao, Licheng; Qiao, Peijun; Zhang, Xiangtao; Li, Qianyu; van Hinsbergen, Douwe J. J.


    The plate kinematic history of the South China Sea opening is key to reconstructing how the Mesozoic configuration of Panthalassa and Tethyan subduction systems evolved into today's complex Southeast Asian tectonic collage. The South China Sea is currently flanked by the Palawan Continental Terrane in the south and South China in the north and the two blocks have long been assumed to be conjugate margins. However, the paleogeographic history of the Palawan Continental Terrane remains an issue of uncertainty and controversy, especially regarding the questions of where and when it was separated from South China. Here we employ detrital zircon U-Pb geochronology and heavy mineral analysis on Cretaceous and Eocene strata from the northern South China Sea and Palawan to constrain the Late Mesozoic-Early Cenozoic provenance and paleogeographic evolution of the region testing possible connection between the Palawan Continental Terrane and the northern South China Sea margin. In addition to a revision of the regional stratigraphic framework using the youngest zircon U-Pb ages, these analyses show that while the Upper Cretaceous strata from the Palawan Continental Terrane are characterized by a dominance of zircon with crystallization ages clustering around the Cretaceous, the Eocene strata feature a large range of zircon ages and a new mineral group of rutile, anatase, and monazite. On the one hand, this change of sediment compositions seems to exclude the possibility of a latest Cretaceous drift of the Palawan Continental Terrane in response to the Proto-South China Sea opening as previously inferred. On the other hand, the zircon age signatures of the Cretaceous-Eocene strata from the Palawan Continental Terrane are largely comparable to those of contemporary samples from the northeastern South China Sea region, suggesting a possible conjugate relationship between the Palawan Continental Terrane and the eastern Pearl River Mouth Basin. Thus, the Palawan Continental

  12. Reconstructing Changes in Deep Ocean Temperature and Global Carbon Cycle during the Early Eocene Warming Trend: High-Resolution Benthic Stable Isotope Records from the SE Atlantic. (United States)

    Lauretano, V.; Zachos, J. C.; Lourens, L. J.


    From the late Paleocene to the early Eocene, Earth's surface temperatures generally rose, resulting in an increase of at least 5°C in the deep ocean and culminating in the Early Eocene Climatic Optimum (EECO). This long-term warming was punctuated by a series of short-lived global warming events known as "hyperthermals", of which the Paleocene-Eocene Thermal Maximum (PETM) represents the most extreme example. At least two other short-term episodes have been identified as hyperthermals: the ETM2 (or Elmo event) at about 53.7 Myr and the ETM3 (or X-event) at about 52.5 Myr. These transient events are marked by prominent carbon isotope excursions (CIEs), recorded in marine and continental sedimentary sequences and driven by fast and massive injections of 13C-depleted carbon into the ocean-atmosphere system. Recently, evidence has indicated the presence of a regular series of hyperthermal events following the peak in temperatures of the EECO. However, continuous records are needed to investigate short- and long- term changes in the climate system throughout the Early Eocene warming trend. Here, we present new high-resolution benthic stable isotope records of the Early Eocene from ODP Site 1263, (Walvis Ridge, SE Atlantic). The carbon and oxygen records document changes in deep-sea temperature and global carbon cycle encompassing the Early Eocene hyperthermal events and the EECO interval. The transition phase to the post-EECO events is distinct by the decoupling of carbon and oxygen isotopes on the long-term scale. Spectral and wavelet analyses suggest the influence of orbital forcing, specifically long and short eccentricity cycles.

  13. Phototransduction in primate cones and blowfly photoreceptors : different mechanisms, different algorithms, similar response

    NARCIS (Netherlands)

    Hateren, J.H. van; Snippe, H.P.

    Phototransduction in primate cones is compared with phototransduction in blowfly photoreceptor cells. Phototransduction in the two cell types utilizes not only different molecular mechanisms, but also different signal processing steps, producing range compression, contrast constancy, and an

  14. Primate Primordial Germ Cells Acquire Transplantation Potential by Carnegie Stage 23

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    Amander T. Clark


    Full Text Available Primordial germ cells (PGCs are the earliest embryonic progenitors in the germline. Correct formation of PGCs is critical to reproductive health as an adult. Recent work has shown that primate PGCs can be differentiated from pluripotent stem cells; however, a bioassay that supports their identity as transplantable germ cells has not been reported. Here, we adopted a xenotransplantation assay by transplanting single-cell suspensions of human and nonhuman primate embryonic Macaca mulatta (rhesus macaque testes containing PGCs into the seminiferous tubules of adult busulfan-treated nude mice. We discovered that both human and nonhuman primate embryonic testis are xenotransplantable, generating colonies while not generating tumors. Taken together, this work provides two critical references (molecular and functional for defining transplantable primate PGCs. These results provide a blueprint for differentiating pluripotent stem cells to transplantable PGC-like cells in a species that is amenable to transplantation and fertility studies.

  15. Non human primate models for Alzheimer's disease-related research and drug discovery

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    Van Dam, Debby; De Deyn, Peter Paul


    Introduction: Pathophysiological mechanisms underlying Alzheimer's disease (AD) remain insufficiently documented for the identification of accurate diagnostic markers and purposeful target discovery and development. Nonhuman primates (NHPs) have important translational value given their close

  16. Dengue viruses cleave STING in humans but not in nonhuman primates, their presumed natural reservoir (United States)

    Stabell, Alex C; Meyerson, Nicholas R; Gullberg, Rebekah C; Gilchrist, Alison R; Webb, Kristofor J; Old, William M; Perera, Rushika


    Human dengue viruses emerged from primate reservoirs, yet paradoxically dengue does not reach high titers in primate models. This presents a unique opportunity to examine the genetics of spillover versus reservoir hosts. The dengue virus 2 (DENV2) - encoded protease cleaves human STING, reducing type I interferon production and boosting viral titers in humans. We find that both human and sylvatic (reservoir) dengue viruses universally cleave human STING, but not the STING of primates implicated as reservoir species. The special ability of dengue to cleave STING is thus specific to humans and a few closely related ape species. Conversion of residues 78/79 to the human-encoded ‘RG’ renders all primate (and mouse) STINGs sensitive to viral cleavage. Dengue viruses may have evolved to increase viral titers in the dense and vast human population, while maintaining decreased titers and pathogenicity in the more rare animals that serve as their sustaining reservoir in nature. PMID:29557779

  17. New adenoviruses from new primate hosts - growing diversity reveals taxonomic weak points

    Czech Academy of Sciences Publication Activity Database

    Dadáková, E.; Chrudimský, Tomáš; Brožová, K.; Modrý, David; Celer, V.; Hrazdilová, K.


    Roč. 107, February (2017), s. 305-307 ISSN 1055-7903 Institutional support: RVO:60077344 Keywords : adenovirus * primate * phylogeny * taxonomy Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 4.419, year: 2016

  18. The ten-thousand year fever: rethinking human and wild primate malarias

    National Research Council Canada - National Science Library

    Cormier, Loretta A


    "Malaria is one of the oldest recorded diseases in human history, and its 10,000-year relationship to primates can teach us why it will be one of the most serious threats to humanity in the 21st century...

  19. Non-human Primate Models for Brain Disorders - Towards Genetic Manipulations via Innovative Technology. (United States)

    Qiu, Zilong; Li, Xiao


    Modeling brain disorders has always been one of the key tasks in neurobiological studies. A wide range of organisms including worms, fruit flies, zebrafish, and rodents have been used for modeling brain disorders. However, whether complicated neurological and psychiatric symptoms can be faithfully mimicked in animals is still debatable. In this review, we discuss key findings using non-human primates to address the neural mechanisms underlying stress and anxiety behaviors, as well as technical advances for establishing genetically-engineered non-human primate models of autism spectrum disorders and other disorders. Considering the close evolutionary connections and similarity of brain structures between non-human primates and humans, together with the rapid progress in genome-editing technology, non-human primates will be indispensable for pathophysiological studies and exploring potential therapeutic methods for treating brain disorders.

  20. A solution to the worn tooth conundrum in primate functional anatomy


    Ungar, Peter S.; M'Kirera, Francis


    Worn teeth are a bane to paleobiologists interested in the diets of human ancestors and other fossil primates. Although worn teeth dominate fossil assemblages, their shapes are usually not used to reconstruct the diets of extinct species. The problem is that traditional studies of primate dental functional anatomy have focused on unworn morphology. This has limited most functional analyses to only a few well-represented fossil species. This paper introduces a method to characterize and compar...

  1. The Role of Endorphins in the Pathophysiology of Hemorrhagic and Endotoxic Shock in the Primate. (United States)


    reverse side it necesaryv mif Identify by block nhmeber) shock, endorphins, naloxone, hemrrhage, endotoxemia , primate shock, opiate receptors...temperature, and metabolic measure- ments. Naloxone improved LV dp/dt max by 800 mm Hg/sec compared to no change with saline (p<.02 by ANOVA, Figure 2... endotoxemia study suggest that endorphin systems are activated in and contribute to the cardiovascular pathophysiology of endotoxemic shock in primates

  2. Human and non-human primate genomes share hotspots of positive selection.

    Directory of Open Access Journals (Sweden)

    David Enard


    Full Text Available Among primates, genome-wide analysis of recent positive selection is currently limited to the human species because it requires extensive sampling of genotypic data from many individuals. The extent to which genes positively selected in human also present adaptive changes in other primates therefore remains unknown. This question is important because a gene that has been positively selected independently in the human and in other primate lineages may be less likely to be involved in human specific phenotypic changes such as dietary habits or cognitive abilities. To answer this question, we analysed heterozygous Single Nucleotide Polymorphisms (SNPs in the genomes of single human, chimpanzee, orangutan, and macaque individuals using a new method aiming to identify selective sweeps genome-wide. We found an unexpectedly high number of orthologous genes exhibiting signatures of a selective sweep simultaneously in several primate species, suggesting the presence of hotspots of positive selection. A similar significant excess is evident when comparing genes positively selected during recent human evolution with genes subjected to positive selection in their coding sequence in other primate lineages and identified using a different test. These findings are further supported by comparing several published human genome scans for positive selection with our findings in non-human primate genomes. We thus provide extensive evidence that the co-occurrence of positive selection in humans and in other primates at the same genetic loci can be measured with only four species, an indication that it may be a widespread phenomenon. The identification of positive selection in humans alongside other primates is a powerful tool to outline those genes that were selected uniquely during recent human evolution.

  3. Social isolation disrupts hippocampal neurogenesis in young non-human primates


    Cinini, Simone M.; Barnabe, Gabriela F.; Galvão-Coelho, Nicole; de Medeiros, Magda A.; Perez-Mendes, Patrícia; Sousa, Maria B. C.; Covolan, Luciene; Mello, Luiz E.


    Social relationships are crucial for the development and maintenance of normal behavior in non-human primates. Animals that are raised in isolation develop abnormal patterns of behavior that persist even when they are later reunited with their parents. In rodents, social isolation is a stressful event and is associated with a decrease in hippocampal neurogenesis but considerably less is known about the effects of social isolation in non-human primates during the transition from adolescence to...

  4. Did trichromatic color vision and red hair color coevolve in primates? (United States)

    Kamilar, Jason M; Heesy, Christopher P; Bradley, Brenda J


    Reddish pelage and red hair ornaments have evolved many times, independently, during primate evolution. It is generally assumed that these red-coat phenotypes, like red skin phenotypes, play a role in sociosexual signaling and, thus evolved in tandem with conspecific color vision. This study examines the phylogenetic distribution of color vision and pelage coloration across the primate order to ask: (1) did red pelage and trichromacy coevolve; or (2) did trichromacy evolve first, and then subsequently red pelage evolved as an exaptation? We collected quantitative, color-corrected photographic color data for 142 museum research skins from 92 species representing 41 genera spanning all major primate lineages. For each species, we quantified the ratio of Red/Green values (from a RGB color model) at 20 anatomical landmarks. For these same species, we compiled data on color vision type (routine trichromatic, polymorphic, routine dichromatic, monochromatic) and data on variables that potentially covary with visual system (VS) and coloration, including activity pattern and body mass dimorphism (proxy for sexual selection). We also considered whether the long-term storage of research skins might influence coloration. Therefore, we included the time since the specimen was collected as an additional predictor. Analyzing the data with phylogenetic generalized least squares models, we found that the amount of red hair present in primates is associated with differences in VSs, but not in the direction expected. Surprisingly, trichromatic primate species generally exhibited less red hair compared to red-green colorblind species. Thus, our results do not support the general assumption that color vision and red pelage coloration are a coevolutionary product of sociosexual signaling in primates. In addition, we did not find an effect of activity pattern, body mass dimorphism, or time since collection on the redness of primate hair. Our results have important implications for the

  5. Deep Hierarchies in the Primate Visual Cortex: What Can We Learn for Computer Vision?


    Kruger, Norbert; Janssen, Peter; Kalkan, Sinan; Lappe, Markus; Leonardis, Ales; Piater, Justus; Rodriguez-Sanchez, Antonio J.; Wiskott, Laurenz


    Computational modeling of the primate visual system yields insights of potential relevance to some of the challenges that computer vision is facing, such as object recognition and categorization, motion detection and activity recognition or vision-based navigation and manipulation. This article reviews some functional principles and structures that are generally thought to underlie the primate visual cortex, and attempts to extract biological principles that could further advance computer ...

  6. Distribution, ecology, life history, genetic variation, and risk of extinction of nonhuman primates from Costa Rica


    Zaldívar, María E.; Rocha, Oscar; Glander, Kenneth E.; Aguilar, Gabriel; Huertas, Ana S; Sánchez, Ronald; Wong, Grace


    We examined the association between geographic distribution, ecological traits, life history, genetic diversity, and risk of extinction in nonhuman primate species from Costa Rica. All of the current nonhuman primate species from Costa Rica are included in the study; spider monkeys (Ateles geoffroyi), howling monkeys (Alouatta palliata), capuchins (Cebus capucinus), and squirrel monkeys (Saimiri oerstedii). Geographic