Sample records for ancestral pacific gondwana

  1. Using ancient DNA to study the origins and dispersal of ancestral Polynesian chickens across the Pacific. (United States)

    Thomson, Vicki A; Lebrasseur, Ophélie; Austin, Jeremy J; Hunt, Terry L; Burney, David A; Denham, Tim; Rawlence, Nicolas J; Wood, Jamie R; Gongora, Jaime; Girdland Flink, Linus; Linderholm, Anna; Dobney, Keith; Larson, Greger; Cooper, Alan


    The human colonization of Remote Oceania remains one of the great feats of exploration in history, proceeding east from Asia across the vast expanse of the Pacific Ocean. Human commensal and domesticated species were widely transported as part of this diaspora, possibly as far as South America. We sequenced mitochondrial control region DNA from 122 modern and 22 ancient chicken specimens from Polynesia and Island Southeast Asia and used these together with Bayesian modeling methods to examine the human dispersal of chickens across this area. We show that specific techniques are essential to remove contaminating modern DNA from experiments, which appear to have impacted previous studies of Pacific chickens. In contrast to previous reports, we find that all ancient specimens and a high proportion of the modern chickens possess a group of unique, closely related haplotypes found only in the Pacific. This group of haplotypes appears to represent the authentic founding mitochondrial DNA chicken lineages transported across the Pacific, and allows the early dispersal of chickens across Micronesia and Polynesia to be modeled. Importantly, chickens carrying this genetic signature persist on several Pacific islands at high frequencies, suggesting that the original Polynesian chicken lineages may still survive. No early South American chicken samples have been detected with the diagnostic Polynesian mtDNA haplotypes, arguing against reports that chickens provide evidence of Polynesian contact with pre-European South America. Two modern specimens from the Philippines carry haplotypes similar to the ancient Pacific samples, providing clues about a potential homeland for the Polynesian chicken.

  2. Circum-Pacific accretion of oceanic terranes to continental blocks: accretion of the Early Permian Dun Mountain ophiolite to the E Gondwana continental margin, South Island, New Zealand (United States)

    Robertson, Alastair


    Accretionary orogens, in part, grow as a result of the accretion of oceanic terranes to pre-existing continental blocks, as in the circum-Pacific and central Asian regions. However, the accretionary processes involved remain poorly understood. Here, we consider settings in which oceanic crust formed in a supra-subduction zone setting and later accreted to continental terranes (some, themselves of accretionary origin). Good examples include some Late Cretaceous ophiolites in SE Turkey, the Jurassic Coast Range ophiolite, W USA and the Early Permian Dun Mountain ophiolite of South Island, New Zealand. In the last two cases, the ophiolites are depositionally overlain by coarse clastic sedimentary rocks (e.g. Permian Upukerora Formation of South Island, NZ) that then pass upwards into very thick continental margin fore-arc basin sequences (Great Valley sequence, California; Matai sequence, South Island, NZ). Field observations, together with petrographical and geochemical studies in South Island, NZ, summarised here, provide evidence of terrane accretion processes. In a proposed tectonic model, the Early Permian Dun Mountain ophiolite was created by supra-subduction zone spreading above a W-dipping subduction zone (comparable to the present-day Izu-Bonin arc and fore arc, W Pacific). The SSZ oceanic crust in the New Zealand example is inferred to have included an intra-oceanic magmatic arc, which is no longer exposed (other than within a melange unit in Southland), but which is documented by petrographic and geochemical evidence. An additional subduction zone is likely to have dipped westwards beneath the E Gondwana margin during the Permian. As a result, relatively buoyant Early Permian supra-subduction zone oceanic crust was able to dock with the E Gondwana continental margin, terminating intra-oceanic subduction (although the exact timing is debatable). The amalgamation ('soft collision') was accompanied by crustal extension of the newly accreted oceanic slab, and

  3. Introducing a novel mechanism to control heart rate in the ancestral Pacific hagfish. (United States)

    Wilson, Christopher M; Roa, Jinae N; Cox, Georgina K; Tresguerres, Martin; Farrell, Anthony P


    Although neural modulation of heart rate is well established among chordate animals, the Pacific hagfish (Eptatretus stoutii) lacks any cardiac innervation, yet it can increase its heart rate from the steady, depressed heart rate seen in prolonged anoxia to almost double its normal normoxic heart rate, an almost fourfold overall change during the 1-h recovery from anoxia. The present study sought mechanistic explanations for these regulatory changes in heart rate. We provide evidence for a bicarbonate-activated, soluble adenylyl cyclase (sAC)-dependent mechanism to control heart rate, a mechanism never previously implicated in chordate cardiac control.

  4. 40Ar/39Ar Thermochronometry of the Sisters Shear Zone, Stewart Island, New Zealand; Implications for Driving Mechanisms and Multi-Stage Breakup of the Pacific Margin of Gondwana (United States)

    Kula, J. L.; Tulloch, A. J.; Spell, T. L.; Wells, M. L.


    New mapping, structural analysis, and thermochronometry of the Sisters Shear Zone (SSZ) indicate this detachment system played a role in continental extension leading to separation of New Zealand from West Antarctica. The SSZ extends 40 km along the southeast coast of Stewart Island, southernmost New Zealand with a footwall consisting of variably deformed 300-105 Ma granites and a hanging wall of coarse non-marine conglomerate and undeformed granite. The trace of the SSZ is subparallel to seafloor isochrons adjacent to the Campbell Plateau and stretching lineations throughout the shear zone are oriented 155/335° ± 10°; consistent with the spreading direction along the Pacific-Antarctic Ridge. Mica and K-feldspar 40Ar/39Ar thermochronometry of SSZ footwall rocks indicate moderately rapid cooling (20-30°C/Ma) over the interval ~89-82 Ma followed by slow cooling. Interpretation of the moderately rapid cooling as due to tectonic denudation makes the SSZ the youngest structure yet identified in New Zealand related to Gondwana breakup. The decrease in cooling rate at 82 Ma coincides with the age of oldest seafloor adjacent to the Campbell Plateau (chron 33r), possibly reflecting the mechanical transition from continental extension to lithospheric rupture and Pacific-Antarctic ridge initiation. The orientation of the SSZ has implications for driving mechanisms of extension. Major arc/forearc terrains through South Island and Stewart Island trend northwest-southeast, and include paired plutonic belts of thick inboard arc terrain adjacent to a thin older, outboard arc belt. Crustal collapse due to the across-arc gradient in gravitational potential energy would have resulted in extension directed normal to the arc trend. The SSZ cuts the paired plutonic belts at a high angle indicating extension was not the result of gravitational collapse, but more likely driven by plate boundary forces such as microplate capture as the dynamics of subduction along the continental

  5. Unraveling the New England orocline, east Gondwana accretionary margin (United States)

    Cawood, P. A.; Pisarevsky, S. A.; Leitch, E. C.


    The New England orocline lies within the Eastern Australian segment of the Terra Australis accretionary orogen and developed during the late Paleozoic to early Mesozoic Gondwanide Orogeny (310-230 Ma) that extended along the Pacific margin of the Gondwana supercontinent. The orocline deformed a pre-Permian arc assemblage consisting of a western magmatic arc, an adjoining forearc basin and an eastern subduction complex. The orocline is doubly vergent with the southern and northern segments displaying counter-clockwise and clockwise rotation, respectively, and this has led to contrasting models of formation. We resolve these conflicting models with one that involves buckling of the arc system about a vertical axis during progressive northward translation of the southern segment of the arc system against the northern segment, which is pinned relative to cratonic Gondwana. Paleomagnetic data are consistent with this model and show that an alternative model involving southward motion of the northern segment relative to the southern segment and cratonic Gondwana is not permissible. The timing of the final stage of orocline formation (˜270-265 Ma) overlaps with a major gap in magmatic activity along this segment of the Gondwana margin, suggesting that northward motion and orocline formation were driven by a change from orthogonal to oblique convergence and coupling between the Gondwana and Pacific plates.

  6. Jurassic fishes of Gondwana

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    Adriana López-Arbarello


    Full Text Available The Jurassic is an important period for understanding the origin of modern fish faunas, since it saw the first radiation - and in some cases the origin - of most modern groups. In chondrichthyans, neoselachian sharks and rays diversified during this time. In actinopterygians, the neopterygians, and among them the teleosts, experienced an important radiation, which led to the appearance of several of the modern teleosts groups. In the sarcopterygians, dipnoans and actinistians approached their current forms. However, the Jurassic fossil record of fishes is strongly biased towards the Northern Hemisphere. The only notable Early Jurassic fish fauna from Gondwana is that of the Kota Formation of India. For the Middle Jurassic, the most important Gondwanan fish faunas are those of the Aalenian-Bathonian Stanleyville Beds of the Democratic Republic of Congo, in which a distinct freshwater and a marine fauna are found. In the Late Jurassic, the Gondwanan record is slightly better, with important marine faunas being known from the Oxfordian Quebrada del Profeta in Chile and the Tithonian Vaca Muerta Formation of Argentina. Freshwater faunas have been described from the Tithonian Talbragar Beds of eastern Australia and the Tithonian Cañadón Calcáreo Formation of Argentina. The taxonomic composition of the known marine actinopterygian faunas of Gondwana is in general agreement with faunas of the Northern Hemisphere. However, the Jurassic fish record from Gondwana is highly incomplete both stratigraphically and geographically, and most faunas are in need of revision, further hampering an interpretation of Jurassic fish evolution in the Southern Hemisphere.

  7. Gondwana to Asia: Preface (United States)

    Kwon, Sanghoon; Kim, Sung Won; Santosh, M.


    The Korean Peninsula, China, Japan, India, Sri Lanka, and Timor, among other regions, preserve important clues for the tectonic evolution of present-day Asia derived from the break-up of Mesozoic supercontinent Pangea. Evidence for the formation, evolution, and destruction of Earth's first coherent supercontinent Columbia during Paleoproterozoic, followed by the Neoproterozoic Rodinia and late Neoproterozoic-Cambrian Gondwana supercontinents are also recorded in many of these regions. The debates surrounding some of these aspects and the state-of-the-art knowledge from these terranes were the focal themes of discussion during the "2013 Annual Convention of the International Association for Gondwana Research (IAGR) and the 10th Gondwana to Asia International Conference" held at the Korea Institute of Geoscience and Mineral Resources (KIGAM), Korea during September 30th to October 2nd 2013. The conference was attended by more than 200 delegates representing 11 countries. The discussion continued at the "International conference on Continental Dynamics" held in Xian, China during April 2014. This special issue of Journal of Asian Earth Sciences, assembling 24 research papers is an outcome of the deliberations under various sessions of the above conferences. In assembling this special issue, we attempt to provide evidence-driven discussions on the construction and destruction of Precambrian and Paleozoic supercontinents preserved in present-day Asian continents. We also address a variety of themes including magmatic, metamorphic and metallogenic processes, as well as issues related to natural environment. We hope that the papers assembled in this special issue offer new insights into some of the key issues surrounding the geological, geophysical and geodynamic milieu in Asia, and a better understanding of analogous processes in other parts of the world.

  8. Ancestral Relationships Using Metafounders

    DEFF Research Database (Denmark)

    Legarra, Andres; Christensen, Ole Fredslund; Vitezica, Zulma G


    due to finite size of the ancestral population and connections between populations. This complicates the conciliation of both approaches and, in particular, combining pedigree with genomic relationships. We present a coherent theoretical framework to consider base population in pedigree relationships....... We suggest a conceptual framework that considers each ancestral population as a finite-sized pool of gametes. This generates across-individual relationships and contrasts with the classical view where each population is considered as an infinite, unrelated pool. Several ancestral populations may......Recent use of genomic (marker-based) relationships shows that relationships exist within and across base population (breeds or lines). However, current treatment of pedigree relationships is unable to consider relationships within or across base populations, although such relationships must exist...

  9. Continental Arc Magmatism and its Abrupt Termination by Ridge Subduction or Ridge Jump Along the Proto-Pacific Margin of Gondwana, Marie Byrd Land, Antarctica: A Zircon U-Pb Study (United States)

    Mukasa, S. B.


    The Paleozoic and Mesozoic development and subsequent fragmentation of Gondwanaland's Pacific margin is recorded in igneous and metamorphic rocks cropping out in the Marie Byrd Land (MBL) continental block of West Antarctica, recognized on geologic and paleomagnetic grounds to comprise a distinct microplate. Widespread occurrence of metaluminous granitoids dated by the zircon U-Pb method as mid- to late Paleozoic shows that convergence-related magmatism dominated the early evolution of this margin. Dates for granodiorites, monzogranites and granites from the Ruppert and Hobbs Coasts of western MBL reveal a prolonged period of subduction-related calc-alkaline magmatism between at least 320 ñ 3 Ma (age of the oldest granodiorite dated) and 110 ñ1 Ma (the age of the Mt. Prince granite). The latter is intruded by swarms of mafic and intermediate dikes believed to record the onset of rifting that led to separation of the New Zealand microcontinent from MBL. The dikes have been dated by zircon U-Pb at 101 ñ 1 Ma. Thus, the regime along the Ruppert and Hobbs Coasts had shifted from subduction-related to rift-related magmatism within a mere ~9-m.y. period. In the Kohler Range and the Pine Island Bay areas of eastern MBL, the calc-alkaline magmatism did not terminate until 96 ñ 1 Ma, based on U-Pb dating of zircons from one granitoid sample, or 94 ñ 3 Ma based on zircons from another. No continental separation occurred to the east of MBL. The margins of the Thurston Island and Antarctic Peninsula blocks went directly from convergent to inactive. With their zircon U-Pb ages clustering around 100 ñ 2 Ma, dike-free "anorogenic" syenites and quartz syenites along the Ruppert and Hobbs Coasts show that the transition to extensional magmatism was rapid in the west. This is also reflected by the fact that from the onset of rifting at 101 ñ 1 Ma to formation of oceanic crust between MBL and Greater New Zealand (Campbell Plateau, Chatham Rise, North Island and South Island

  10. Are palaeoscolecids ancestral ecdysozoans? (United States)

    Harvey, Thomas H P; Dong, Xiping; Donoghue, Philip C J


    The reconstruction of ancestors is a central aim of comparative anatomy and evolutionary developmental biology, not least in attempts to understand the relationship between developmental and organismal evolution. Inferences based on living taxa can and should be tested against the fossil record, which provides an independent and direct view onto historical character combinations. Here, we consider the nature of the last common ancestor of living ecdysozoans through a detailed analysis of palaeoscolecids, an early and extinct group of introvert-bearing worms that have been proposed to be ancestral ecdysozoans. In a review of palaeoscolecid anatomy, including newly resolved details of the internal and external cuticle structure, we identify specific characters shared with various living nematoid and scalidophoran worms, but not with panarthropods. Considered within a formal cladistic context, these characters provide most overall support for a stem-priapulid affinity, meaning that palaeoscolecids are far-removed from the ecdysozoan ancestor. We conclude that previous interpretations in which palaeoscolecids occupy a deeper position in the ecdysozoan tree lack particular morphological support and rely instead on a paucity of preserved characters. This bears out a more general point that fossil taxa may appear plesiomorphic merely because they preserve only plesiomorphies, rather than the mélange of primitive and derived characters anticipated of organisms properly allocated to a position deep within animal phylogeny.

  11. South China's Gondwana connection in the Paleozoic:Paleomagnetic evidence

    Institute of Scientific and Technical Information of China (English)

    ZHANG Shihong


    The reconstruction in which the South China Block (SCB) lies along the Great India-Australia region of Gondwana margin is tested by using existing Paleozoic paleomagnetic data.Under the proposed reconstruction, all six high quality paleopoles from the SCB between the Early Cambrian and late Early Devonian (~400 Ma) are in good agreement with coeval paleopoles from Gondwana.Thereafter, the apparent polar wander paths for the SCB and Gondwana diverge markedly.This indicates that the SCB had been part of Gondwana and the connection was intact from at least Early Cambrian until late Early Devonian, but they began to separate by late Middle Devonian (~375 Ma).

  12. Correlating early evolution of parasitic platyhelminths to Gondwana breakup. (United States)

    Badets, Mathieu; Whittington, Ian; Lalubin, Fabrice; Allienne, Jean-Francois; Maspimby, Jean-Luc; Bentz, Sophie; Du Preez, Louis H; Barton, Diane; Hasegawa, Hideo; Tandon, Veena; Imkongwapang, Rangpenyuba; Imkongwapang, Rangpenyubai; Ohler, Annemarie; Combes, Claude; Verneau, Olivier


    Investigating patterns and processes of parasite diversification over ancient geological periods should involve comparisons of host and parasite phylogenies in a biogeographic context. It has been shown previously that the geographical distribution of host-specific parasites of sarcopterygians was guided, from Palaeozoic to Cainozoic times, mostly by evolution and diversification of their freshwater hosts. Here, we propose phylogenies of neobatrachian frogs and their specific parasites (Platyhelminthes, Monogenea) to investigate coevolutionary processes and historical biogeography of polystomes and further discuss all the possible assumptions that may account for the early evolution of these parasites. Phylogenetic analyses of concatenated rRNA nuclear genes (18S and partial 28S) supplemented by cophylogenetic and biogeographic vicariance analyses reveal four main parasite lineages that can be ascribed to centers of diversity, namely Australia, India, Africa, and South America. In addition, the relationships among these biogeographical monophyletic groups, substantiated by molecular dating, reflect sequential origins during the breakup of Gondwana. The Australian polystome lineage may have been isolated during the first stages of the breakup, whereas the Indian lineage would have arisen after the complete separation of western and eastern Gondwanan components. Next, polystomes would have codiverged with hyloid sensu stricto and ranoid frog lineages before the completion of South American and African plate separation. Ultimately, they would have undergone an extensive diversification in South America when their ancestral host families diversified. Therefore, the presence of polystome parasites in specific anuran host clades and in discrete geographic areas reveals the importance of biogeographic vicariance in diversification processes and supports the occurrence and radiation of amphibians over ancient and recent geological periods.

  13. Isotopic characterisation of the sub-continental lithospheric mantle beneath Zealandia, a rifted fragment of Gondwana

    DEFF Research Database (Denmark)

    Waight, Tod Earle; Scott, James M.; van der Meer, Quinten Har Adriaan


    and that contained a HIMU component. The volcanics have tapped two adjacent but chemically contrasting upper mantle domains: a fertile eastern domain and an extremely depleted western domain. Both domains underlie Mesozoic metasedimentary crust. Radiogenic isotope compositions of the clinopyroxene have 87Sr/86Sr......The greater New Zealand region, known as Zealandia, represents an amalgamation of crustal fragments accreted to the paleo-Pacific Gondwana margin and which underwent significant thinning during the subsequent split from Australia and Antarctica in the mid-Cretaceous following opening of the Tasman...

  14. Ancestral process and diffusion model with selection

    CERN Document Server

    Mano, Shuhei


    The ancestral selection graph in population genetics introduced by Krone and Neuhauser (1997) is an analogue to the coalescent genealogy. The number of ancestral particles, backward in time, of a sample of genes is an ancestral process, which is a birth and death process with quadratic death and linear birth rate. In this paper an explicit form of the number of ancestral particle is obtained, by using the density of the allele frequency in the corresponding diffusion model obtained by Kimura (1955). It is shown that fixation is convergence of the ancestral process to the stationary measure. The time to fixation of an allele is studied in terms of the ancestral process.

  15. Jurassic fishes of Gondwana Peces jurásicos de Gondwana

    Directory of Open Access Journals (Sweden)

    Adriana López-Arbarello


    Full Text Available The Jurassic is an important period for understanding the origin of modern fish faunas, since it saw the first radiation - and in some cases the origin - of most modern groups. In chondrichthyans, neoselachian sharks and rays diversified during this time. In actinopterygians, the neopterygians, and among them the teleosts, experienced an important radiation, which led to the appearance of several of the modern teleosts groups. In the sarcopterygians, dipnoans and actinistians approached their current forms. However, the Jurassic fossil record of fishes is strongly biased towards the Northern Hemisphere. The only notable Early Jurassic fish fauna from Gondwana is that of the Kota Formation of India. For the Middle Jurassic, the most important Gondwanan fish faunas are those of the Aalenian-Bathonian Stanleyville Beds of the Democratic Republic of Congo, in which a distinct freshwater and a marine fauna are found. In the Late Jurassic, the Gondwanan record is slightly better, with important marine faunas being known from the Oxfordian Quebrada del Profeta in Chile and the Tithonian Vaca Muerta Formation of Argentina. Freshwater faunas have been described from the Tithonian Talbragar Beds of eastern Australia and the Tithonian Cañadón Calcáreo Formation of Argentina. The taxonomic composition of the known marine actinopterygian faunas of Gondwana is in general agreement with faunas of the Northern Hemisphere. However, the Jurassic fish record from Gondwana is highly incomplete both stratigraphically and geographically, and most faunas are in need of revision, further hampering an interpretation of Jurassic fish evolution in the Southern Hemisphere.El Período Jurásico es muy importante para entender el origen de las ictiofaunas modernas, dado que evidenció la primera radiación - y en algunos casos el origen - de la mayoría de los grupos modernos. Así, los condrictios neoselacios se diversificaron durante este periodo. Los actinopterigios

  16. Ordovician rafinesquinine brachiopods from peri-Gondwana

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    Jorge Colmenar


    Full Text Available The study of the strophomenide brachiopods of the subfamily Rafinesquininae present in the main Upper Ordovician sections, representing the Mediterranean margin of Gondwana, has revealed an increase in diversity of the group at the region during that time. The studied collections are from the Moroccan Anti-Atlas, the Iberian and the Armorican massifs, the Iberian Chains, Pyrenees, Montagne Noire, Sardinia, and Bohemia. Two genera of the subfamily Rafinesquininae have been recorded. Of them, the cosmopolitan Rafinesquina is the only one previously reported from the region and Kjaerina is found for the first time outside Avalonia, Baltica, and Laurentia. Additionally, two new subgenera have been described, Kjaerina (Villasina and Rafinesquina (Mesogeina. Furthermore, the new species Rafinesquina (Mesogeina gabianensis, Rafinesquina (Mesogeina loredensis, Kjaerina (Kjaerina gondwanensis, Kjaerina (Villasina pedronaensis, Kjaerina (Villasina pyrenaica, and Kjaerina (Villasina meloui have been described. In addition, other species of these genera previously known from isolated localities in the region, such as Rafinesquina pseudoloricata, Rafinesquina pomoides, and Hedstroemina almadenensis are revised and their geographic range expanded. The adaptive radiation experienced by the rafinesquinines at the Mediterranean region during middle to late Katian, was probably related to changes in the regime of sedimentation and water temperature caused by the global warming Boda event.

  17. Patterns of Gondwana plant colonisation anddiversification (United States)

    Anderson, J. M.; Anderson, H. M.; Archangelsky, S.; Bamford, M.; Chandra, S.; Dettmann, M.; Hill, R.; McLoughlin, S.; Rösler, O.

    Charting the broad patterns of vascular plant evolution for Gondwana againstthe major global environmental shifts and events is attempted here for the first time. This is based on the analysis of the major vascular plant-bearing formations of the southern continents (plus India) correlated against the standard geological time-scale. Australia, followed closely by South America, are shown to yield by far the most complete sequences of productive strata. Ten seminal turnover pulses in the unfolding evolutionary picture are identified and seen to be linked to continental drift, climate change and mass global extinctions. The rise of vascular plants along the tropical belt, for instance, followed closely after the end-Ordovician warming and extinction. Equally remarkable is that the Late Devonian extinction may have caused both the terrestrialisation of the vertebrates and the origin of the true gymnosperms. The end-Permian extinction, closure of Iapetus, together with warming, appears to have set in motion an unparalleled, explosive, gymnosperm radiation; whilst the Late Triassic extinction dramatically curtailed it. It is suggested that the latitudinal diversity gradient clearly recognised today, where species richness increases towards the tropics, may have been partly reversed during phases of Hot House climate. Evidence hints at this being particularly so at the heyday of the gymnosperms in the Late Triassic super-Hot House world. As for the origin of terrestrial, vascular, plant life, the angiosperms seem closely linked to a phase of marked shift from Ice House to Hot House. Insect and tetrapod evolutionary patterns are discussed in the context of the plants providing the base of the ever-changing ecosystems. Intimate co-evolution is often evident. This isn't always the case, for example the non-linkage between the dominant, giant, long-necked, herbivorous sauropod dinosaurs and the dramatic radiation of the flowering plants in the Mid Cretaceous.

  18. Inherited crustal deformation along the East Gondwana margin revealed by seismic anisotropy tomography (United States)

    Pilia, S.; Arroucau, P.; Rawlinson, N.; Reading, A. M.; Cayley, R. A.


    The mechanisms of continental growth are a crucial part of plate tectonic theory, yet a clear understanding of the processes involved remains elusive. Here we determine seismic Rayleigh wave phase anisotropy variations in the crust beneath the southern Tasmanides of Australia, a Paleozoic accretionary margin. Our results reveal a complex, thick-skinned pervasive deformation that was driven by the tectonic interaction between the proto-Pacific Ocean and the ancient eastern margin of Gondwana. Stress-induced effects triggered by the collision and entrainment of a microcontinent into the active subduction zone are evident in the anisotropy signature. The paleofracturing trend of failed rifting between Australia and Antarctica is also recorded in the anisotropy pattern as well as a tightly curved feature in central Tasmania. The observed patterns of anisotropy correlate well with recent geodynamic and kinematic models of the Tasmanides and provide a platform from which the spatial extent of deformational domains can be refined.

  19. Evidence of post-Gondwana breakup in Southern Brazilian Shield: Insights from apatite and zircon fission track thermochronology (United States)

    Oliveira, Christie Helouise Engelmann de; Jelinek, Andréa Ritter; Chemale, Farid; Bernet, Matthias


    Apatite and zircon fission track thermochronology studies are applied to basement and sedimentary rocks from the Sul-Rio-Grandense Shield to unravel the tectonic history of the onshore southernmost Brazilian margin. The Sul-Rio-Grandense Shield is a major geotectonic feature of southernmost Brazil that includes Paleoproterozoic basement areas and Neoproterozoic fold belts linked to the Brasiliano/Pan-African orogeny. Crustal reworking and juvenile accretion events related to this cycle were dated in the region between 900 and 500 Ma and were responsible for the assembly of southwestern Gondwana in southeastern South America. Apatite fission track (AFT) ages range from 340 ± 33 to 77 ± 6 Ma and zircon fission track (ZFT) ages range from ca. 386 to 210 Ma. Based on thermal history modeling, the most part of the samples record an early cooling event during the Carboniferous, which reflect the main tectonic activity of the final stages of the Gondwanides at the Pacific margin of West Gondwana. Subsequently, the Permo-Triassic cooling event is related to the last stages of the Gondwanides, with convergence along the southern border of Western Gondwana and consequent reactivation of N-S and NE-SW trending basement structures. The onset of initial breakup of southwestern Gondwana with opening of the South Atlantic Ocean is mostly recorded in the eastern terrain and ZFT ages show that the temperature during this period was high enough for total or at least partial resetting of fission tracks in zircon. The last cooling event of the Sul-Rio-Grandense Shield records the final breakup between South America and Africa, which began during the Late Cretaceous. However, the Cenozoic rapid cooling episode probably is a result of plate adjustment after breakup and neotectonic reactivation of faults associated with South Atlantic rift evolution.

  20. Kinematics of late paleozoic continental collision between laurentia and gondwana. (United States)

    Sacks, P E; Secor, D T


    In the Appalachians, late Paleozoic Alleghanian orogenesis is widely regarded as resulting from dextral oblique collision between irregular margins of Gondwana and Laurentia. However, this relative plate motion cannot account for coeval convergence in the Ouachitas and Variscides and is incompatible with some tectonic transport indicators in the Appalachians. An alternative kinematic model is proposed in which early sinistral transpression in the Appalachians is followed by counterclockwise rotation of Gondwana and the development of a system of dextral strike-slip faults extending from southern Europe to Alabama.

  1. Paleomagnetism of some Gondwana red beds from central India

    NARCIS (Netherlands)

    Wensink, H.


    Oriented samples were collected for paleomagnetic research from red horizons of the Gondwana sediments at a few localities in central India. The specimens were subjected to both alternating-field and thermal demagnetization and were measured on astatic magnetometers. Usually a stable direction of ma

  2. Gondwana to Pangea: a detrital zircons tale from NW Iberia (United States)

    Pastor-Galán, Daniel; Gutiérrez-Alonso, Gabriel; Brendan Murphy, J.; Fernández-Suárez, Javier; Hofmann, Mandy; Linnemann, Ulf


    The Cantabrian Zone of NW Iberia preserves a voluminous, almost continuous, sedimentary sequence that ranges from Neoproterozoic to Early Permian in age. Its tectonic setting is controversial and recent hypotheses include (i) passive margin deposition along the northern margin of Gondwana or (ii) an active continental margin or (iii) a drifting ribbon continent. In this paper we present detrital zircon U-Pb laser ablation age data from 13 samples from the Cantabrian Zone sequence ranging from Early Silurian to Early Permian in depositional age, which, together with previously published detrital zircon ages from Ediacaran-Ordovician strata, allow a comprehensive analysis of changing provenance through time. Laser ablation U-Pb geochronological analysis of detrital zircons in thirteen samples of the Cantabrian Zone of the NW Iberian Variscan belt reveal that this portion of Iberia was part of the northern passive-margin of Gondwana from the Ordovician to Late Devonian, until the onset of collision between Gondwana and Laurentia. Zircon populations in these samples show important similarities with zircons found in coeval detrital rocks from central North Africa. Additionally, the populations found in NW Iberia are coherent with a Saharan source. We suggest that NW Iberia was situated from Ordovician to Late Devonian along the Gondwana northern passive margin close to the paleoposition of central North Africa and Saharan craton. Additionally, the Carboniferous-Permian samples studied record the provenance changes produced during the Variscan collision and basement exhumation, the Cantabrian orocline formation and the subsequent detachment of the lithospheric mantle. The provenance changes reflect major topographic variations due to the afore mentioned processes during Late Devonian to Early Permian times. Detrital zircon studies are a useful tool that can complement regional syntheses in deducing paleogeographic locations, the occurrence of major tectonic events such

  3. Panjal Paleomagnetism: Implications for Early Permian Gondwana break-up (United States)

    Stojanovic, D.; Aitchison, J.; Ali, J. R.; Ahmad, T.; Ahmad Dar, R.; Agarwal, A.; Roeder, T.


    The mid-Early Permian represents an important phase in Pangaea's development marking the time when the >13,000 km-long string of terranes that are collectively known as 'Cimmeria' separated from Gondwana's Tethyan margin (northern Africa-NE Arabia-northern India-NW and northern Australia). The ~289 Ma Panjal Traps of NW India (Kashmir) are one of a number of mafic suites (Abor, Sikkim etc.) that were erupted onto the Indian block possibly during the separation of the Lhasa/SE Qiangtang block. Herein, we report data from the first modern paleomagnetic study of the unit. Results from four quarry sections (15 individual cooling units) from a locality close to Srinagar together form a tectonically coherent sequence spanning 2-3 km of stratigraphy. The derived direction and paleopole yield key new information concerning (1) the Early Permian location of India, and by inference that of central Gondwana, and (2) inform debates related to Cimmeria's breakup from eastern Gondwana. Moreover, they provide a new independent control for assessing NW Greater India's extent prior to its collision with Asia and the amount of vertical-axis rotation this sector of the Himalayan range experienced in the mid to late Cenozoic.

  4. New Views of East Antarctica- from Columbia to Gondwana (United States)

    Ferraccioli, F.; Forsberg, R.; Aitken, A.; Young, D. A.; Blankenship, D. D.; Bell, R. E.; Finn, C.; Martos, Y. M.; Armadillo, E.; Jacobs, J.; Ebbing, J.; Eagles, G.; Jokat, W.; Jordan, T. A.; Ruppel, A.; Läufer, A.; Dalziel, I. W. D.


    East Antarctica is a keystone in the Gondwana, Rodinia and the Columbia supercontinents. Recent aerogeophysical research, augmented by satellite magnetic, gravity and seismological data is unveiling the crustal architecture of the continent. This is helping comprehend the impact of supercontinental processes such as subduction, accretion, rifting and intraplate tectonics on its evolution. A mosaic of Precambrian basement provinces is apparent in interior East Antarctica (Ferraccioli et al., 2011, Nature). A major suture separates the Archean-Neoproterozoic Ruker Province from an inferred Grenvillian-age orogenic Gamburtsev Province with remarkably thick crust (up to 60 km thick) and thick lithosphere (over 200 km thick). The age of the suturing and its linkages with supercontinental assembly is debated with both Rodinia and Gondwana candidates being proposed. Further east, magnetic highs delineate a Paleo to Mesoproterozoic Nimrod-South Pole igneous province (Goodge and Finn, 2010 JGR) that flanks a composite Mawson Continent- including the Gawler Craton of South Australia (Aitken et al., 2014 GRL). An over 1,900 km long magnetic and gravity lineament is imaged along the western flank of the Wilkes Subglacial Basin and is interpreted here as a major Paleoproterozoic suture zone linked to the collision of Laurentia and East Antarctica within Columbia. The proposed suture played a pivotal role helping localise Neoproterozoic Rodinia rifted margin evolution and forming a backstop for the Ross-Delamerian cycle of Gondwana amalgamation. Aeromagnetic and gravity imaging help determine the extent of a Keweenawan-age (ca 1.1 Ga) large igneous province in the Coats Land Block -isotopically tied with the Mid-Continent Rift System of Laurentia (Loewy et al., 2011 Geology). Imprints of Grenvillian magmatic arc accretion link together the Namaqua-Natal and Maud belts in South Africa and Dronning Maud Land within Rodinia. The aeromagnetically distinct Southeast Dronning Maud

  5. Permian plate margin volcanism and tuffs in adjacent basins of west Gondwana: Age constraints and common characteristics (United States)

    López-Gamundí, Oscar


    Increasing evidence of Permian volcanic activity along the South American portion of the Gondwana proto-Pacific margin has directed attention to its potential presence in the stratigraphic record of adjacent basins. In recent years, tuffaceous horizons have been identified in late Early Permian-through Middle Permian (280-260 Ma) sections of the Paraná Basin (Brazil, Paraguay, and Uruguay). Farther south and closer to the magmatic tract developed along the continental margin, in the San Rafael and Sauce Grande basins of Argentina, tuffs are present in the Early to Middle Permian section. This tuff-rich interval can be correlated with the appearance of widespread tuffs in the Karoo Basin. Although magmatic activity along the proto-Pacific plate margin was continuous during the Late Paleozoic, Choiyoi silicic volcanism along the Andean Cordillera and its equivalent in Patagonia peaked between the late Early Permian and Middle Permian, when extensive rhyolitic ignimbrites and consanguineous airborne tuffaceous material erupted in the northern Patagonian region. The San Rafael orogenic phase (SROP) interrupted sedimentation along the southwestern segment of the Gondwana margin (i.e., Frontal Cordillera, San Rafael Basin), induced cratonward thrusting (i.e., Ventana and Cape foldbelts), and triggered accelerated subsidence in the adjacent basins (Sauce Grande and Karoo) located inboard of the deformation front. This accelerated subsidence favored the preservation of tuffaceous horizons in the syntectonic successions. The age constraints and similarities in composition between the volcanics along the continental margin and the tuffaceous horizons in the San Rafael, Sauce Grande, Paraná, and Karoo basins strongly suggest a genetic linkage between the two episodes. Radiometric ages from tuffs in the San Rafael, Paraná, and Karoo basins indicate an intensely tuffaceous interval between 280 and 260 Ma.

  6. Assessment of Hydrocarbon Generation Potential of Permian Gondwana Coals, Bangladesh

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    H. M. Zakir Hossain


    Full Text Available This paper represents the geochemical characteristics of Gondwana coals from the Barapukuria coal mine, Bangladesh in order to investigate the potential for hydrocarbon generation. A total number of twenty three coal samples were analyzed Rock-Eval pyrolysis, CHNS elemental analyses, maceral analysis and vitrinite reflectance. The samples were collected from drill hole GDH-40 of the Barapukuria coal mine encountered within Gondwana succession of Permian age. The TOC contents of the coal samples range between ~50 and 76 wt.% and the organic matter consists predominantly of type III and type IV kerogen with respect to hydrocarbon generation. The GP, HI, PI and Tmax values range between 7 and 35 mg HC/g rock, 20 and 62 mg HC/g TOC, 0.02 and 0.04, and 430 and 437oC, respectively. The organic matter is mainly gas prone and thermally immature to early mature level. The potential coal bed methane (CBM generation of the Barapukuria basin is estimated to be 11 Gm3. Thus, underground coal gasification (UCG is helpful for better development of subsurface coals at the Barapukuria basin, Bangladesh.

  7. Paleogeography of Southwest Gondwana Boundary During the Upper Paleozoic (United States)

    Tomezzoli, R. N.


    Current results are summarized from the southwest Gondwana boundary, from rocks from La Pampa province, Argentina. This area is the westward part of an orogenic belt, known as Sam Frau geosincline or Cordón de las Gondwánides and may represent the suture zone between the Gondwana and Patagonia terranes. This collision model is still uncertain and there are many controversies related to the age of the deformation of this belt. Paleomagnetism and the exploration of the magnetic fabric signatures (AMS) can be useful to evaluate the regional deformation and a better understanding of the assembly, deformation, and fragmentation of Gondwana / Pangea. A systematic paleomagnetic study was done in the Cerro Centinela: 36/deg S, 67/deg W, belong to the Choiyoi Group and consist of Lower Paleozoic volcanic rocks. In this paleomagnetic study is present results from 19 sites (84 specimens), sampled from the base to the top in different layers. Samples were demagnetized with thermal procedures. A high un¬blocking temperature component carried by hematite was defined between 580° C and 680° C, showing very good within site consistency (alpha 9520). Remanent magnetization ranges around 1500 mA m-1. In all samples it was possible to isolate one component with the same behavior and positive inclination. These stable remanent magnetization were group into two different Population: 1 and 2, clearly separated. Population 1 (from sites 1 to 12) in situ mean direction is: D=146°, I=63.5°, alpha 95=4°, k=104, N=12. Population 2 (from sites 13 to 19) in situ mean direction is: D=164°, I=42°, alpha 95=4°, k=197, N=7. Reversed characteristic remanence magnetization suggesting that the magnetization was acquired during the Kiaman interval, in accordance with their age. Two high quality paleomagnetic poles were computed for each population on the basis of the in situ remanence directions. The corresponding PP are for Population 1: 63° S, 353° E, Alpha 95=7 and K=44 and for

  8. Optimized ancestral state reconstruction using Sankoff parsimony

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    Valiente Gabriel


    Full Text Available Abstract Background Parsimony methods are widely used in molecular evolution to estimate the most plausible phylogeny for a set of characters. Sankoff parsimony determines the minimum number of changes required in a given phylogeny when a cost is associated to transitions between character states. Although optimizations exist to reduce the computations in the number of taxa, the original algorithm takes time O(n2 in the number of states, making it impractical for large values of n. Results In this study we introduce an optimization of Sankoff parsimony for the reconstruction of ancestral states when ultrametric or additive cost matrices are used. We analyzed its performance for randomly generated matrices, Jukes-Cantor and Kimura's two-parameter models of DNA evolution, and in the reconstruction of elongation factor-1α and ancestral metabolic states of a group of eukaryotes, showing that in all cases the execution time is significantly less than with the original implementation. Conclusion The algorithms here presented provide a fast computation of Sankoff parsimony for a given phylogeny. Problems where the number of states is large, such as reconstruction of ancestral metabolism, are particularly adequate for this optimization. Since we are reducing the computations required to calculate the parsimony cost of a single tree, our method can be combined with optimizations in the number of taxa that aim at finding the most parsimonious tree.

  9. Plate motions, Gondwana Dinosaurs, Noah's Arks, Beached Viking Funeral Ships, Ghost Ships, and Landspans

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    Louis L. Jacobs


    Full Text Available Gondwana landmasses have served as large-scale biogeographic Noah's Arks and Beached Viking Funeral Ships, as defined by McKenna. The latitudinal trajectories of selected Gondwana dinosaur localities were traced through time in order to evaluate their movement through climate zones relative to those in which they originally formed. The dispersal of fauna during the breakup of Gondwana may have been facilitated by the presence of offshelf islands forming landspans (sensu Iturralde-Vinent and MacPhee in the Equatorial Atlantic Gateway and elsewhere.As massas de terra do Gondwana serviram como Arcas de Noe biogeograficas de grande escala e Navios Funerarios Vikings encalhados, conforme definido por McKenna. As trajetorias latitudinais de areas selecionadas de dinossauros do Gondwana foram tracadas ao longo do tempo a fim de avaliar seu movimento atraves de zonas climaticas relativas aquelas nas quais elas foram originalmente formadas. A dispersao da fauna durante a quebra do Gondwana pode ter sido facilitada pela presenca de ilhas oceanicas formando extensoes de terra (sensu Iturralde-Vinent e MacPhee na entrada do Atlantico Equatorial e em outros lugares.

  10. Cordillera Zealandia: A Mesozoic arc flare-up on the palaeo-Pacific Gondwana Margin. (United States)

    Milan, L A; Daczko, N R; Clarke, G L


    Two geochemically and temporally distinct components of the Mesozoic Zealandia Cordilleran arc indicate a shift from low to high Sr/Y whole rock ratios at c. 130 Ma. Recent mapping and a reappraisal of published Sr-Nd data combined with new in-situ zircon Hf isotope analyses supports a genetic relationship between the two arc components. A reappraisal of geophysical, geochemical and P-T estimates demonstrates a doubling in thickness of the arc to at least 80 km at c. 130 Ma. Contemporaneously, magmatic addition rates shifted from ~14 km(3)/my per km of arc to a flare-up involving ~100 km(3)/my per km of arc. Excursions in Sr-Nd-Hf isotopic ratios of flare-up rocks highlight the importance of crust-dominated sources. This pattern mimics Cordilleran arcs of the Americas and highlights the importance of processes occurring in the upper continental plates of subduction systems that are incompletely reconciled with secular models for continental crustal growth.

  11. Reconstructing ancestral ranges in historical biogeography: properties and prospects

    Institute of Scientific and Technical Information of China (English)

    Kristin S. LAMM; Benjamin D. REDELINGS


    Recent years have witnessed a proliferation of quantitative methods for biogeographic inference. In particular, novel parametric approaches represent exciting new opportunities for the study of range evolution. Here, we review a selection of current methods for biogeographic analysis and discuss their respective properties. These methods include generalized parsimony approaches, weighted ancestral area analysis, dispersal-vicariance analysis, the dispersal-extinction-cladogenesis model and other maximum likelihood approaches, and Bayesian stochastic mapping of ancestral ranges, including a novel approach to inferring range evolution in the context of island biogeography. Some of these methods were developed specifically for problems of ancestral range reconstruction, whereas others were designed for more general problems of character state reconstruction and subsequently applied to the study of ancestral ranges. Methods for reconstructing ancestral history on a phylogenetic tree differ not only in the types of ancestral range states that are allowed, but also in the various historical events that may change the ancestral ranges. We explore how the form of allowed ancestral ranges and allowed transitions can both affect the outcome of ancestral range estimation. Finally, we mention some promising avenues for future work in the development of model-based approaches to biogeographic analysis.

  12. First evidence of Hadrosauropodus in Gondwana (Yacoraite Formation, Maastrichtian-Danian), northwestern Argentina (United States)

    Díaz-Martínez, Ignacio; de Valais, Silvina; Cónsole-Gonella, Carlos


    Uppermost Cretaceous (Campanian-Maastrichtian) large ornithopod tracks are scarce in Gondwana. This record is limited to few citations in the northern Argentina, Peru and possibly Bolivia, although their ichnological affinities are still under discussion. Recently, a new vertebrate tracksite with large ornithopod tracks has been found in the Maimará locality, Jujuy province, Argentina, from the Yacoraite Formation (Maastrichtian-Danian). The best preserved track is characterized by having large and bilobed heel impression and wide and short digit impressions with blunt claw marks. This record represents the unambiguous record of large ornithopod tracks in Gondwana in the Uppermost Cretaceous, and its features allow classifying it as Hadrosauropodus. Previously, this ichnotaxon had exclusively Laurasian distribution. Therefore, this record is the first evidence of Hadrosauropodus from Gondwana expanding the geographic range of this ichnogenus. A member of Hadrosauridae is reinforced as possible trackmaker of the Hadrosauropodus tracks. Uppermost Cretaceous hadrosaurid dinosaurs are scarce in Gondwana, being the record limited to Patagonia, La Pampa province and Antarctica. Therefore, the Maimará tracks increase the knowledge of this kind of dinosaur from Gondwana.

  13. Ancestral Area Analysis of the Genus Caragara (Leguminosae)

    Institute of Scientific and Technical Information of China (English)



    Caragana has a temperate Asian distribution. Based on the phylogeny and 13 distributionalareas of this genus, its ancestral area was studied via the ancestral area analysis suggested by Bremer(1992), Ronquist (1994) and Hausdorf (1997). The results indicate that three areas, Far East-NortheastChina, Altai-Sayan and North China-Qinling Mountains (Mts) are likely the ancestral areas. Linking to theviewpoints of the Holarctic origin for north temperate flora, Far East-Northeast China seems more likely tobe the ancestral area. According to the three ancestral areas isolated geographically and the analysis inthe present study, as well as former biogeographical analysis of this genus, it is suggested that Caraganaspeciation is mainly in the mode of vicariance rather than dispersal, and dispersed is often in shortdistance.

  14. Why Meillassoux’s Speculative Materialism Struggles with Ancestrality

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    Ciprian Jeler


    Full Text Available This paper shows that Quentin Meillassoux’s speculative materialism doesn’t offer us the means to account for the ancestral statements that the modern sciences produce, i.e. for the scientific statements about events preceding all forms of life. An analysis of the reasons why Meillassoux thinks that the problem of ancestrality problematizes the contemporary self-evidence of correlationism is first offered. The results of this analysis are then applied to speculative materialism itself and the consequences are not very promising: very much like correlationism, speculative materialism explicitly denies what I call the “generalized version of the realistic assumption of science” and, in so doing, renders scientific ancestral statements de jure unverifiable. Therefore, if correlationism is rendered suspicious by the issue of ancestrality, the same can be said of speculative materialism.

  15. Plant biodiversity in the Mahanadi Basin, India, during the Gondwana period

    Energy Technology Data Exchange (ETDEWEB)

    Singh, K.J. [Birbal Sahni Institute of Paleobotany, Lucknow (India)


    The Mahanadi Basin is one of five major sedimentary basins of Peninsular India. The sediments are exposed in two different regions: an extensive basin comprising Lower to Upper Gondwana with coal measures towards the west (Talchir and Ib-River Sub-basins); and the Athgarh Sub-basin in the east with rocks of only Upper Gondwana age. This study was mainly concerned with plant species diversification and the development of flora in the Mahanadi Basin from the Early Permian to the Early Cretaceous. A number of successive megafloras were recognised with gaps in the sequence. Leaves were the dominant part of the preserved flora, followed by fruits. Maximum plant diversification in gymnosperms was recorded in the Late Permian (Kamthi Formation), and in pteridophytes in the Early Cretaceous (Athgarh Formation).

  16. Early Paleozoic paleogeography of Laurentia and western Gondwana: Evidence from tectonic subsidence analysis (United States)

    Williams, Kenneth E.


    A number of terranes were present in the early Paleozoic ocean between Laurentia and Gondwana following rifting. The precise location of these microcontinents and island arcs is unclear. We present tectonic subsidence curves from selected basins that may provide some constraints on the possible paleogeographic interpretations for this time interval. Among these tectonic blocks were the Precordillera terrane that originated in the Ouachita area of Laurentia and the composite Avalon-Carolina terrane that was derived from the Gondwana margin. Also present were the island-arc terranes of Famatina, Mixteca, and Zapoteca. The Precordillera and Famatina terranes are currently located in southern South America. The Avalon-Carolina terrane is in eastern North America. The Mixteca and Zapoteca terranes are in Central America. A review of previous work augmented by new tectonic subsidence analysis indicates that these terranes were swept up by early Paleozoic plate movements and were translated to approximately their present relative positions by the Early Carboniferous.

  17. Paleozoic terranes of eastern Australia and the drift history of Gondwana (United States)

    McElhinny, Michael W.; Powell, Chris McA.; Pisarevsky, Sergei A.


    Critical assessment of Paleozoic paleomagnetic results from Australia shows that paleopoles from locations on the main craton and in the various terranes of the Tasman Fold Belt of eastern Australia follow the same path since 400 Ma for the Lachlan and Thomson superterranes, but not until 250 Ma or younger for the New England superterrane. Most of the paleopoles from the Tasman Fold Belt are derived from the Lolworth-Ravenswood terrane of the Thomson superterrane and the Molong-Monaro terrane of the Lachlan superterrane. Consideration of the paleomagnetic data and geological constraints suggests that these terranes were amalgamated with cratonic Australia by the late Early Devonian. The Lolworth-Ravenswood terrane is interpreted to have undergone a 90° clockwise rotation between 425 and 380 Ma. Although the Tamworth terrane of the western New England superterrane is thought to have amalgamated with the Lachlan superterrane by the Late Carboniferous, geological syntheses suggest that movements between these regions may have persisted until the Middle Triassic. This view is supported by the available paleomagnetic data. With these constraints, an apparent polar wander path for Gondwana during the Paleozoic has been constructed after review of the Gondwana paleomagnetic data. The drift history of Gondwana with respect to Laurentia and Baltica during the Paleozoic is shown in a series of paleogeographic maps.

  18. Record of Lower Gondwana megafloral assemblage from the Nand coalfield, Wardha Basin, Nagpur District, Maharashtra

    Energy Technology Data Exchange (ETDEWEB)

    Singh, K.J.; Sarate, O.S.; Bhattacharya, A.P.; Goswami, S. [Birbal Sahni Institute for Paleobotany, Lucknow (India)


    A rich collection of Lower Gondwana mega-plant fossils have been recorded from the outcrops exposed along the Kharkhara Nala section in Nand coalfield, Nagpur District, Maharashtra, mapped as Lameta Formation. The Lower Gondwana rocks are deposited mainly in Nagpur, Chandrapur and Yeotmal Districts of Maharashtra. Palaeobotanical investigations (megafloral and xylotomical) so far known from Wardha Valley are mostly confined to Barakar and Kamthi Formations. Megafloral assemblage very similar to assemblage of Karharbari Formation has been recovered for the first time from the Lower Gondwana beds exposed in the Nand coalfield. The plant assemblage consists of two species of Gangamopteris, one species each of the genera Buriadia, Noeggerathiopsis and Allatocarpus along with the genus Glossopteris represented by seven species; the conifer genus Buriadia dominates the flora (17.72%) followed by Glossopteris communis (16.46%). The sediments were also investigated for the purpose of palynology but no pollen and spore types could be recovered. An Early Permian age has been assigned on the basis of overall assemblage.

  19. Early Paleozoic paleogeography of the northern Gondwana margin: new evidence for Ordovician-Silurian glaciation (United States)

    Semtner, A.-K.; Klitzsch, E.


    During the Early Paleozoic, transgressions and the distribution of sedimentary facies on the northern Gondwana margin were controlled by a regional NNW-SSE to almost north-south striking structural relief. In Early Silurian times, a eustatic highstand enabled the sea to reach its maximum southward extent. The counterclockwise rotation of Gondwana during the Cambrian and Early Ordovician caused the northern Gondwana margin to shift from intertropical to southern polar latitudes in Ordovician times. Glacial and periglacial deposits are reported from many localities in Morocco, Algeria, Niger, Libya, Chad, Sudan, Jordan and Saudi Arabia. The Late Ordovician glaciation phase was followed by a period of a major glacioeustatic sea-level rise in the Early Silurian due to the retreat of the ice-cap. As a consequence of the decreasing water circulation in the basin centers (Central Arabia, Murzuk- and Ghadames basins), highly bituminous euxinic shales were deposited. These shales are considered to be the main source rock of Paleozoic oil and gas deposits in parts of Saudi Arabia, Libya and Algeria. The following regression in the southern parts of the Early Silurian sea was probably caused by a second glacial advance, which was mainly restricted to areas in Chad, Sudan and Niger. Evidence for glacial activity and fluvioglacial sedimentation is available from rocks overlying the basal Silurian shale in north-east Chad and north-west Sudan. The Early Silurian ice advance is considered to be responsible for the termination of euxinic shale deposition in the basin centers.

  20. Musculature in sipunculan worms: ontogeny and ancestral states. (United States)

    Schulze, Anja; Rice, Mary E


    Molecular phylogenetics suggests that the Sipuncula fall into the Annelida, although they are morphologically very distinct and lack segmentation. To understand the evolutionary transformations from the annelid to the sipunculan body plan, it is important to reconstruct the ancestral states within the respective clades at all life history stages. Here we reconstruct the ancestral states for the head/introvert retractor muscles and the body wall musculature in the Sipuncula using Bayesian statistics. In addition, we describe the ontogenetic transformations of the two muscle systems in four sipunculan species with different developmental modes, using F-actin staining with fluorescent-labeled phalloidin in conjunction with confocal laser scanning microscopy. All four species, which have smooth body wall musculature and less than the full set of four introvert retractor muscles as adults, go through developmental stages with four retractor muscles that are eventually reduced to a lower number in the adult. The circular and sometimes the longitudinal body wall musculature are split into bands that later transform into a smooth sheath. Our ancestral state reconstructions suggest with nearly 100% probability that the ancestral sipunculan had four introvert retractor muscles, longitudinal body wall musculature in bands and circular body wall musculature arranged as a smooth sheath. Species with crawling larvae have more strongly developed body wall musculature than those with swimming larvae. To interpret our findings in the context of annelid evolution, a more solid phylogenetic framework is needed for the entire group and more data on ontogenetic transformations of annelid musculature are desirable.

  1. Ancestral gene synteny reconstruction improves extant species scaffolding. (United States)

    Anselmetti, Yoann; Berry, Vincent; Chauve, Cedric; Chateau, Annie; Tannier, Eric; Bérard, Sèverine


    We exploit the methodological similarity between ancestral genome reconstruction and extant genome scaffolding. We present a method, called ARt-DeCo that constructs neighborhood relationships between genes or contigs, in both ancestral and extant genomes, in a phylogenetic context. It is able to handle dozens of complete genomes, including genes with complex histories, by using gene phylogenies reconciled with a species tree, that is, annotated with speciation, duplication and loss events. Reconstructed ancestral or extant synteny comes with a support computed from an exhaustive exploration of the solution space. We compare our method with a previously published one that follows the same goal on a small number of genomes with universal unicopy genes. Then we test it on the whole Ensembl database, by proposing partial ancestral genome structures, as well as a more complete scaffolding for many partially assembled genomes on 69 eukaryote species. We carefully analyze a couple of extant adjacencies proposed by our method, and show that they are indeed real links in the extant genomes, that were missing in the current assembly. On a reduced data set of 39 eutherian mammals, we estimate the precision and sensitivity of ARt-DeCo by simulating a fragmentation in some well assembled genomes, and measure how many adjacencies are recovered. We find a very high precision, while the sensitivity depends on the quality of the data and on the proximity of closely related genomes.

  2. Perianth evolution in Ranunculaceae: are petals ancestral in the family?

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    Sophie Nadot


    Full Text Available Progress has been made recently towards the elucidation of phylogenetic relationships among subfamilies and tribes of the Ranunculaceae – the most recent hypothesis was published in 2016 by our team. Although relationships among the 10 tribes of the subfamily Ranunculoideae remain incompletely supported, this hypothesis provides an interesting framework to address the key issue of the ancestral vs. derived nature of a differentiated perianth within the family, and at the level of Ranunculales as a whole. Here, we present ancestral state reconstructions for several perianth characters, such as differentiation into sepals and petals, shape of petals, presence/absence of nectaries, and petaloid or sepaloid aspect of sepals. Characters were scored using the PROTEUS database and optimized on the most recent phylogeny of Ranunculaceae using parsimony and maximum likelihood methods. The results are discussed with regard to recent evo-devo studies focused on identifying genes involved in floral organs identity (the so-called ABC model in Ranunculales.

  3. The Basement of the Andes: the Gondwana-Laurentia Connections Revisited (United States)

    Ramos, V. A.


    The research performed in the last decade in the basement of the Andes have shown that the Precambrian and Paleozoic rocks have recorded a series of igneous and metamorphic events through time. These episodes can be grouped in discrete orogenic events, which have different paleogeographic distribution and intensity. The first and most important orogenic event is widely distributed along the margin and correspond to the Sunsas-Grenville orogen. Evidence of metamorphism and associated magmatic rocks are found from Colombia to the southernmost Patagonia. This episode produced the amalgamation of Amazonia, Pampia and Patagonia, among other cratonic blocks, to form Rodinia. The Rodinia break-up leaved several cratonic blocks accreted in the Gondwana side, such as Marañón, Arequipa, and Antofalla, although the generalized extension of this period produced crustal attenuation, rifted basins, and limited oceanic realms during late Proterozoic times. The Brasiliano-Pampean orogeny reamalgamated these blocks against the Gondwana margin. A new episode of break-up produced the dispersal of several Gondwanian blocks, separation along some previous sutures, crustal attenuation and magmatism in Late Cambrian times, until the new amalgamation occurred in Middle Late Ordovician times. These processes led to the Famatinian orogeny when metamorphism and arc magmatism was widely spread along the continental margin, as seen in Chibcha, Marañón, Arequipa and Sierras Pampeanas. Besides the re-accretion of some parautochthonous terranes, new exotic blocks were derived from Laurentia, such as the Cuyania terrane, which finally collided against the Andean proto-margin at ~ 460 Ma to form the Argentine Precordillera and surrounding regions. Late accretion in Early to Middle Devonian times of Chilenia and related terranes formed most of the basement of Central Andes. Final collision between Laurentia and Gondwana in the Late Carboniferous - Early Permian times to form the Alleghanides

  4. A Marchantialean thallus from the Lower Gondwana Sequence of Godavari basin, Andhra Pradesh

    Energy Technology Data Exchange (ETDEWEB)

    Sarate, O.S.; Budhraja, N. [Birbal Sahni Institute of Paleobotany, Lucknow (India)


    The present paper deals with the critical observation of a thallus section recorded in one of the samples prepared for the coal petrographic study (Pellet No. 3). This sample represents a coal band lying above the 'Queen seam' from Koyagudem area of the Godavari valley coalfield, Andhra Pradesh. The shape of this specimen in transverse section and its cellular organization very closely resemble the anatomical features of extant thalli of the bryophytic (liverwort) family Rebouliaceae, a big group of Marchantiales (Hepaticopsida). A thallus with cellular details assignable to Hepaticae is recorded from the Lower Gondwana Sequence of Godavari valley coalfield.

  5. Magma sources during Gondwana breakup: chemistry and chronology of Cretaceous magmatism in Westland, New Zealand

    DEFF Research Database (Denmark)

    van der Meer, Quinten Har Adriaan; Waight, Tod Earle; Scott, James M.


    Cretaceous-Paleogene rifting of the Eastern Gondwana margin thinned the continental crust of Zealandia and culminated in the opening of the Tasman Sea between Australia and New Zealand and the Southern Ocean, separating both from Antarctica. The Western Province of New Zealand consists...... of a succession of metasedimentary rocks intruded by Palaeozoic and Mesozoic granitoids that formed in an active margin setting through the Phanerozoic. Upon cessation of subduction, the earliest stages of extension (110-100 Ma) were expressed in the formation of metamorphic core complexes, followed...

  6. A review of the Late Cambrian (Furongian) palaeogeography in the western Mediterranean region, NW Gondwana (United States)

    Álvaro, J. Javier; Ferretti, Annalisa; González-Gómez, Cristina; Serpagli, Enrico; Tortello, M. Franco; Vecoli, Marco; Vizcaïno, Daniel


    The Cambrian-Ordovician transition of the western Mediterranean region (NW Gondwana) is characterized by the record of major erosive unconformities with gaps that range from a chronostratigraphic stage to a series. The hiatii are diachronous and involved progressively younger strata along the Gondwanan margin, from SW (Morocco) to NE (Montagne Noire). They can be related to development of a multi-stage rifting (further North), currently connected to the opening of the Rheic Ocean, and concomitant erosion on southern rift shoulders. The platforms of this margin of Gondwana occupied temperate-water, mid latitudes and were dominated by siliciclastic sedimentation, while carbonate factories were only episodically active in the Montagne-Noire platform. The Upper Cambrian is devoid of significant gaps in the southern Montagne Noire and the Iberian Chains. There, the sedimentation took place in a transgressive-dominated depositional system, with common offshore deposits and clayey substrates, and was bracketed by two major regressive trends. The Late Cambrian is also associated with the record of volcanic activity ( e.g., in the Cantabrian and Ossa-Morena zones, and the northern Montagne Noire), and widespread development of a tectonic instability that led to the episodic establishment of palaeotopographies and record of slope-related facies associations. Several immigration events are recognized throughout the latest Middle Cambrian, Late Cambrian and Tremadocian. The trilobites show a stepwise replacement of Acado-Baltic-type families ( e.g., the conocoryphid-paradoxidid-solenopleurid assemblage) characterized by: (i) a late Languedocian (latest Middle Cambrian) co-occurrence of Middle Cambrian trilobite families with the first anomocarid, dorypygid and proasaphiscid invaders; (ii) a Late Cambrian immigration replacing previous faunas, composed of trilobites (aphelaspidids, catillicephalids, ceratopygids, damesellids, eulomids, idahoiids, linchakephalids, lisariids

  7. Geology and coal bed methane resource potential of the Gondwana Barapukuria Coal Basin, Dinajpur, Bangladesh

    Energy Technology Data Exchange (ETDEWEB)

    Islam, Md. Rafiqul; Hayashi, Daigoro [Department of Physics and Earth Sciences Faculty of Science, University of the Ryukyus, Okinawa, 903-0213 (Japan)


    With an area of 5.16 km{sup 2}, the Barapukuria coal deposit is one of the five largest Gondwana coal basins in Bangladesh, and is located in the north west of the country close to the towns of Dinajpur and Saidpur. The existence of the basin was initially indicated by a negative gravity anomaly in oil and gas exploration. Exploration for the deposit was commenced by the Geological Survey of Bangladesh (GSB), with seven surface boreholes that confirmed the existence of a significant coal deposit. The deposit occurs as an asymmetrical synclinal structure with an axis striking approximately N-S. The deposit is limited to the east by a large normal fault which has displaced Archaean metamorphics against the Gondwana sediments. The coal-bearing sediments are comprised of Gondwana Permian-age sandstones, siltstones, subordinate carbonaceous shales, and six correlated coal seams. The Gondwana sediments are unconformably overlain by Tertiary and Quaternary deposits, against which the coal seams are successively subcropped to the west. Within the structural limits of the basin, approximately 377 Mt coal in-situ has been quantified in the six coal seams that range in depth from 118 to 518 m below surface. Due to the synclinal nature of the deposit, the upper coal seams, designated I to V, occur over diminishing areal extent with decreasing depth. The principal seam of interest is the lowermost Seam VI, with a variable thickness across the deposit from 22 m in the northern part of the deposit to more than 42 m in the southern and eastern areas. Development of the Barapukuria Mine, the country's first coal mine, commenced in 1996 with the construction of two vertical shafts. Coal production from Seam VI began in 2005 and continues at the present time. Seam VI coal is high volatile B bituminous rank. About 34 Mt of coal has been estimated as recoverable resources, utilising descensional multi-slice longwall mining. The mine design and development have been severely

  8. Pacific Standard

    Institute of Scientific and Technical Information of China (English)


    The United States pushes for greater economic integration of the Asia-Pacific region Barack Obama has been an active free trade promoter in recent months. The U.S. president signed free trade agreements with South Korea,

  9. Bilingualism (Ancestral Language Maintenance) among Native American, Vietnamese American, and Hispanic American College Students. (United States)

    Wharry, Cheryl


    A survey of 21 Hispanic, 22 Native American, and 10 Vietnamese American college students found that adoption or maintenance of ancestral language was related to attitudes toward ancestral language, beliefs about parental attitudes, and integrative motivation (toward family and ancestral ethnic group). There were significant differences by gender…

  10. The ancestral eutherian karyotype is present in Xenarthra.

    Directory of Open Access Journals (Sweden)

    Marta Svartman


    Full Text Available Molecular studies have led recently to the proposal of a new super-ordinal arrangement of the 18 extant Eutherian orders. From the four proposed super-orders, Afrotheria and Xenarthra were considered the most basal. Chromosome-painting studies with human probes in these two mammalian groups are thus key in the quest to establish the ancestral Eutherian karyotype. Although a reasonable amount of chromosome-painting data with human probes have already been obtained for Afrotheria, no Xenarthra species has been thoroughly analyzed with this approach. We hybridized human chromosome probes to metaphases of species (Dasypus novemcinctus, Tamandua tetradactyla, and Choloepus hoffmanii representing three of the four Xenarthra families. Our data allowed us to review the current hypotheses for the ancestral Eutherian karyotype, which range from 2n = 44 to 2n = 48. One of the species studied, the two-toed sloth C. hoffmanii (2n = 50, showed a chromosome complement strikingly similar to the proposed 2n = 48 ancestral Eutherian karyotype, strongly reinforcing it.

  11. Ancestral facial morphology of Old World higher primates. (United States)

    Benefit, B R; McCrossin, M L


    Fossil remains of the cercopithecoid Victoria-pithecus recently recovered from middle Miocene deposits of Maboko Island (Kenya) provide evidence of the cranial anatomy of Old World monkeys prior to the evolutionary divergence of the extant subfamilies Colobinae and Cercopithecinae. Victoria-pithecus shares a suite of craniofacial features with the Oligocene catarrhine Aegyptopithecus and early Miocene hominoid Afropithecus. All three genera manifest supraorbital costae, anteriorly convergent temporal lines, the absence of a postglabellar fossa, a moderate to long snout, great facial height below the orbits, a deep cheek region, and anteriorly tapering premaxilla. The shared presence of these features in a catarrhine generally ancestral to apes and Old World monkeys, an early ape, and an early Old World monkey indicates that they are primitive characteristics that typified the last common ancestor of Hominoidea and Cercopithecoidea. These results contradict prevailing cranial morphotype reconstructions for ancestral catarrhines as Colobus- or Hylobates-like, characterized by a globular anterior braincase and orthognathy. By resolving several equivocal craniofacial morphocline polarities, these discoveries lay the foundation for a revised interpretation of the ancestral cranial morphology of Catarrhini more consistent with neontological and existing paleontological evidence.

  12. The ancestral eutherian karyotype is present in Xenarthra. (United States)

    Svartman, Marta; Stone, Gary; Stanyon, Roscoe


    Molecular studies have led recently to the proposal of a new super-ordinal arrangement of the 18 extant Eutherian orders. From the four proposed super-orders, Afrotheria and Xenarthra were considered the most basal. Chromosome-painting studies with human probes in these two mammalian groups are thus key in the quest to establish the ancestral Eutherian karyotype. Although a reasonable amount of chromosome-painting data with human probes have already been obtained for Afrotheria, no Xenarthra species has been thoroughly analyzed with this approach. We hybridized human chromosome probes to metaphases of species (Dasypus novemcinctus, Tamandua tetradactyla, and Choloepus hoffmanii) representing three of the four Xenarthra families. Our data allowed us to review the current hypotheses for the ancestral Eutherian karyotype, which range from 2n = 44 to 2n = 48. One of the species studied, the two-toed sloth C. hoffmanii (2n = 50), showed a chromosome complement strikingly similar to the proposed 2n = 48 ancestral Eutherian karyotype, strongly reinforcing it.

  13. Episodic Jurassic to Lower Cretaceous intraplate compression in Central Patagonia during Gondwana breakup (United States)

    Navarrete, César; Gianni, Guido; Echaurren, Andrés; Kingler, Federico Lince; Folguera, Andrés


    From Lower Jurassic to Lower Cretaceous, several intraplate compression events affected discrete sectors of Central Patagonia, under a general context of crustal extension associated with Gondwana breakup. This was demonstrated by means of 2D and 3D seismic and borehole data, which show partial inversion of Lower and Middle Jurassic extensional structures of the Chubut and Cañadón Asfalto basins, during the earliest stages of breakup. A comparison with surrounding areas in Patagonia, where similar Jurassic intraplate compression was described, allowed the discrimination of three discrete pulses of subtle compression (C1: ∼188-185 Ma; C2: ∼170-163; C3: ∼157-136? Ma). Interestingly, episodic intraplate compressional events are closely followed by high flux magmatic events linked to the westward expansion of the Karoo-Ferrar thermal anomaly, which impacted on the lithosphere of southwest Gondwana in Lower Jurassic. In addition, we determined the approximate direction of the main compressive strain (σ1) compatible with other Jurassic intraplate belts of South America. These observations led us to propose a linkage between a thermo mechanically weakened continental crust due to LIPs activity, changes in plate motions and ridge-push forces generated by the opening of the Weddell Sea, in order to explain intraplate shortening, interrupted while Karoo LIPs magmatic invigoration took place.

  14. Visual system evolution and the nature of the ancestral snake. (United States)

    Simões, B F; Sampaio, F L; Jared, C; Antoniazzi, M M; Loew, E R; Bowmaker, J K; Rodriguez, A; Hart, N S; Hunt, D M; Partridge, J C; Gower, D J


    The dominant hypothesis for the evolutionary origin of snakes from 'lizards' (non-snake squamates) is that stem snakes acquired many snake features while passing through a profound burrowing (fossorial) phase. To investigate this, we examined the visual pigments and their encoding opsin genes in a range of squamate reptiles, focusing on fossorial lizards and snakes. We sequenced opsin transcripts isolated from retinal cDNA and used microspectrophotometry to measure directly the spectral absorbance of the photoreceptor visual pigments in a subset of samples. In snakes, but not lizards, dedicated fossoriality (as in Scolecophidia and the alethinophidian Anilius scytale) corresponds with loss of all visual opsins other than RH1 (λmax 490-497 nm); all other snakes (including less dedicated burrowers) also have functional sws1 and lws opsin genes. In contrast, the retinas of all lizards sampled, even highly fossorial amphisbaenians with reduced eyes, express functional lws, sws1, sws2 and rh1 genes, and most also express rh2 (i.e. they express all five of the visual opsin genes present in the ancestral vertebrate). Our evidence of visual pigment complements suggests that the visual system of stem snakes was partly reduced, with two (RH2 and SWS2) of the ancestral vertebrate visual pigments being eliminated, but that this did not extend to the extreme additional loss of SWS1 and LWS that subsequently occurred (probably independently) in highly fossorial extant scolecophidians and A. scytale. We therefore consider it unlikely that the ancestral snake was as fossorial as extant scolecophidians, whether or not the latter are para- or monophyletic.

  15. Estimating ancestral geographical distributions: a Gondwanan origin for aphid parasitoids? (United States)

    Belshaw, R; Dowton, M; Quicke, D L; Austin, A D


    We tested the published hypothesis of a Gondwanan origin for the overwhelmingly northern hemisphere aphid parasitoids (Aphidiinae) as follows: (i) finding their sister group by a phylogenetic analysis of the entire Braconidae (Insecta: Hymenopterai using sequence data from approximately 500 bp fragments of both the nuclear 28S (D2 region) and mitochondrial 16S rDNA genes, (ii) using this sister-group relationship and the more informative 28S D2 gene to estimate the phylogeny of the Aphidiinae and (iii) estimating the ancestral distribution for the Aphidiinae using maximum-likelihood and maximum-parsimony methods. Both methods indicated a Gondwanan origin. PMID:10737407

  16. South China connected to north India in Gondwana: sedimentary basin and detrital provenance analyses (United States)

    Yao, W.; Li, Z. X.; Li, W. X.; Li, X. H.; Yang, J. H.


    The paleoposition of South China during the Ediacaran-Silurian is important for understanding the assembly of Gondwana. We report here the tectonostratigraphic evolution of the Ediacaran-Silurian Nanhua foreland basin in South China, and discuss South China's connection with Gondwana and potential tectonic triggers for both the Wuyi-Yunkai orogeny in South China and the Bhimphedian orogeny in north India. The Nanhua basin was involved in a three-stage evolution, which are: Stage 1 (the Ediacaran-Cambrian) recording the start of tectonic subsidence with turbiditic marine clastic deposition, fed by exotic orogens outboard South China; Stage 2 (the Ordovician to earliest-Silurian) featured by migrating depocentres with dominant shallow marine to deltaic clastic deposition, fed by the local Wuyi-Yunkai orogen; and Stage 3 (the Silurian) showing the arrival of depocentre in the Yangtze Block during the waning stage of the Wuyi-Yunkai orogeny with deltaic deposition in the remanent foreland basin. Detrital zircon analyses of the Ediacaran-Silurian sandstones across the Nanhua basin reveal a prominent age population of 1100-900 Ma (with a peak age at ~980 Ma) and moderate populations of Archean-Paleozoic ages, grossly matching that of crystalline and sedimentary rocks in northern India. Zircon isotopes of the Stage 1 samples suggest three Precambrian episodes of juvenile crustal growth at 3.0 Ga, 2.5 Ga and 1.0 Ga, and a major crustal reworking at 580-500 Ma for the source areas, which are constraint to be northwestern India and its surrounding orogens. Together with other evidence, we propose that South China likely collided with northwestern India during the Gondwana assembly, generated the Bhimphedian orogeny in north India and formed two foreland basins on both the north India and South China sides. Far-field stress of the collision triggered the Ordovician-Silurian Wuyi-Yunkai orogeny in South China. The Stage 2-3 samples in the Nanhua basin of South China were shed

  17. Fast phylogeny reconstruction through learning of ancestral sequences

    CERN Document Server

    Mihaescu, Radu; Rao, Satish


    Given natural limitations on the length DNA sequences, designing phylogenetic reconstruction methods which are reliable under limited information is a crucial endeavor. There have been two approaches to this problem: reconstructing partial but reliable information about the tree (\\cite{Mo07, DMR08,DHJ06,GMS08}), and reaching "deeper" in the tree through reconstruction of ancestral sequences. In the latter category, \\cite{DMR06} settled an important conjecture of M.Steel, showing that, under the CFN model of evolution, all trees on $n$ leaves with edge lengths bounded by the Ising model phase transition can be recovered with high probability from genomes of length $O(\\log n)$ with a polynomial time algorithm. Their methods had a running time of $O(n^{10})$. Here we enhance our methods from \\cite{DHJ06} with the learning of ancestral sequences and provide an algorithm for reconstructing a sub-forest of the tree which is reliable given available data, without requiring a-priori known bounds on the edge lengths o...

  18. The ancestral process of long term seed bank models

    CERN Document Server

    Blath, Jochen; Kurt, Noemi; Spanò, Dario


    We present a new model for the evolution of genetic types in the presence of so-called seed banks, i.e., where individuals may obtain their genetic type from ancestors which have lived in the near as well as the very far past. The classical Wright-Fisher model, as well as a seed bank model with bounded age distribution considered by Kaj, Krone and Lascoux (2001) are special cases of our model. We discern three parameter regimes of the seed bank age distribution, which lead to substantially different behaviour in terms of genetic variability, in particular with respect to fixation of types and time to the most recent common ancestor. We prove that for age distributions with finite mean, the rescaled ancestral process converges to a time-changed Kingman coalescent, while in the case of infinite mean, ancestral lineages might not merge at all with positive probability. Further, we present a construction of the forward in time process in equilibrium. The mathematical methods are based on renewal theory, the urn p...

  19. A gigantic sarcopterygian (tetrapodomorph lobe-finned fish from the upper Devonian of Gondwana (Eden, New South Wales, Australia.

    Directory of Open Access Journals (Sweden)

    Ben Young

    Full Text Available Edenopteron keithcrooki gen. et sp. nov. is described from the Famennian Worange Point Formation; the holotype is amongst the largest tristichopterids and sarcopterygians documented by semi-articulated remains from the Devonian Period. The new taxon has dentary fangs and premaxillary tusks, features assumed to be derived for large Northern Hemisphere tristichopterids (Eusthenodon, Hyneria, Langlieria. It resembles Eusthenodon in ornament, but is distinguished by longer proportions of the parietal compared to the post-parietal shield, and numerous differences in shape and proportions of other bones. Several characters (accessory vomers in the palate, submandibulars overlapping ventral jaw margin, scales ornamented with widely-spaced deep grooves are recorded only in tristichopterids from East Gondwana (Australia-Antarctica. On this evidence Edenopteron gen. nov. is placed in an endemic Gondwanan subfamily Mandageriinae within the Tristichopteridae; it differs from the nominal genotype Mandageria in its larger size, less pointed skull, shape of the orbits and other skull characters. The hypothesis that tristichopterids evolved in Laurussia and later dispersed into Gondwana, and a derived subgroup of large Late Devonian genera dispersed from Gondwana, is inconsistent with the evidence of the new taxon. Using oldest fossil and most primitive clade criteria the most recent phylogeny resolves South China and Gondwana as areas of origin for all tetrapodomorphs. The immediate outgroup to tristichopterids remains unresolved - either Spodichthys from Greenland as recently proposed, or Marsdenichthys from Gondwana, earlier suggested to be the sister group to all tristichopterids. Both taxa combine two characters that do not co-occur in other tetrapodomorphs (extratemporal bone in the skull; non-cosmoid round scales with an internal boss. Recently both 'primitive' and 'derived' tristichopterids have been discovered in the late Middle Devonian of both

  20. Evolução paleozóica da Gondwana


    Dias, Rui; Schmitt, Renata


    Durante o Paleozóico a actuação de diversos ciclos de Wilson levaram, não só à unificação da Gondwana mas também da própria Pangeia. Se alguns destes ciclos são exclusivamente paleozóicos (é o caso do orógeno Varisco nos sectores setentrionais), outros resultam de processos extensivos iniciados no final do Neoproterozóico e cujas fases colisionais só ocorreram no Paleozóico inferior (e.g. orogenia Búzios - SE do Brasil). Neste simpósio serão abordados os processos e mecanismos associados à ev...

  1. Role of fluorescence microscopy in the assessment of Indian Gondwana coals

    Energy Technology Data Exchange (ETDEWEB)

    Singh, B.D. [Birbal Sahni Institute of Paleobotany, Lucknow (India)


    When a light of short wavelength excites organic matter, light of relatively longer wavelength is emitted from it and this phenomenon is known as autofluorescence. The coal maceral analysis under fluorescence mode (blue light/UV light excitation), therefore, has been found to be best suited to properly identify, characterize and quantify hydrogen-rich macerals. Utilising this technique, macerals like bituminite, fluorinite and exsudatinite were recognized for the first time. Certain other macerals (alginite and liptodetrinite), normally mistaken for mineral matter under routine petrographic analysis, were also identified. Fluorescence microscopy, thus, not only added to the overall tally of liptinite group of macerals in Indian Gondwana coals, but also to their quantity. In addition to this, recognition of fluorescing vitrinite (perhydrous vitrinite) significantly contributed to the abundance of hydrogen-rich microconstitutents for these coals.

  2. Record of Lower Gondwana megafloral assemblage from Lower Kamthi Formation of Ib River Coalfield, Orissa, India

    Energy Technology Data Exchange (ETDEWEB)

    Goswami, S. [Birbal Sahni Institute of Paleobotany, Lucknow (India)


    Recent investigations carried out in the Ib River Coalfield, Mahanadi Master Basin, Orissa, identified some fossiliferous beds in the Lower Gondwana deposits. Two exposures of the Lower Kamthi Formation yielded diverse and abundant plant remains, which include Neomariopteris, Vertebraria, and a scale leaf along with 14 Glossopteris species otherwise mapped as Barren Measures and Upper Kamthi formations. Glossopteris indica dominates the flora (22.78%) followed by G. communis (17.72%) and G. browniana (13.92%). Based on megafloral assemblages, different beds exposed at Gopalpur and Laxamanpur Pahar are assigned here to the Lower Kamthi Formation (Late Permian). The floristic composition suggests that a warm and humid climate prevailed during the Late Permian. The status of the Kamthi Formation in the Ib River Coalfield has been redefined in the present study.

  3. A stem acrodontan lizard in the Cretaceous of Brazil revises early lizard evolution in Gondwana. (United States)

    Simões, Tiago R; Wilner, Everton; Caldwell, Michael W; Weinschütz, Luiz C; Kellner, Alexander W A


    Iguanians are one of the most diverse groups of extant lizards (>1,700 species) with acrodontan iguanians dominating in the Old World, and non-acrodontans in the New World. A new lizard species presented herein is the first acrodontan from South America, indicating acrodontans radiated throughout Gondwana much earlier than previously thought, and that some of the first South American lizards were more closely related to their counterparts in Africa and Asia than to the modern fauna of South America. This suggests both groups of iguanians achieved a worldwide distribution before the final breakup of Pangaea. At some point, non-acrodontans replaced acrodontans and became the only iguanians in the Americas, contrary to what happened on most of the Old World. This discovery also expands the diversity of Cretaceous lizards in South America, which with recent findings, suggests sphenodontians were not the dominant lepidosaurs in that continent as previously hypothesized.

  4. Record of Lower Gondwana megafloral assemblage from Lower Kamthi Formation of Ib River Coalfield, Orissa, India

    Indian Academy of Sciences (India)

    Shreerup Goswami


    Recent investigations carried out in the Ib River Coalfield, Mahanadi Master Basin, Orissa, identified some fossiliferous beds in the Lower Gondwana deposits. Two exposures of the Lower Kamthi Formation yielded diverse and abundant plant remains, which include Neomariopteris, Vertebraria, and a scale leaf along with 14 Glossopteris species otherwise mapped as Barren Measures and Upper Kamthi formations. Glossopteris indica dominates the flora (22.78%) followed by G. communis (17.72%) and G. browniana (13.92%). Based on megafloral assemblages, different beds exposed at Gopalpur and Laxamanpur Pahar are assigned here to the Lower Kamthi Formation (Late Permian). The floristic composition suggests that a warm and humid climate prevailed during the Late Permian. The status of the Kamthi Formation in the Ib River Coalfield has been redefined in the present study.

  5. Evolution of the APWP for Gondwana: constraints based on the geology of eastern Australia (United States)

    Briden, J. C.; McElhinny, M. W.


    The many iterations of the APWP for Gondwana over the past 40 years will be reviewed. They involve all the uncertainties that challenge the determination of the correct record: nature of NRM; age and correlation; geography and history of tectonic units etc. Most arguments about the Paleozoic section of this path depend upon the interpretation of results from the various terranes of eastern Australia. The two extreme views are either that none of the results from eastern Australia can be used for APWP definition or that all of them can be used. The terrane geology of eastern Australia is now reasonably well known and the paleomagnetic results can be placed in an appropriate terrane concept. This suggests that the Molong-Monaro terrane, where most results come from, was certainly accreted to the main craton by the Middle Devonian and probably by the Early Devonian. Early Devonian palaemagnetric results from the north and south of eastern Australia confirm this to be the case. However, the often used Late Carboniferous results from glacial horizons in eastern Australia are from the New England Fold Belt, where accretion to the main craton may not have been completed until the Middle Triassic. Results from this region now also confirm this to be the case. Both the geological setting and paleomagnetic results now confirm that the South Pole APWP makes a rapid transition from North Africa to south of South Africa between the Late Ordovician (455 Ma) and the Early Devonian (405 Ma). This places Bolivia and adjacent regions of South America near the south pole in Silurian times, a position supported by sedimentological evidence for glaciation in Bolivia at that time. The pole then loops back across southwest Gondwana to reach central Africa by the Early Carboniferous.

  6. Paleomagnetism of the Newcastle Range, northern Queensland: Eastern Gondwana in the Late Paleozoic (United States)

    Anderson, Kari L.; Lackie, Mark A.; Clark, David A.; Schmidt, Phil W.


    The Newcastle Range is an extensive (2500 km2) and well-exposed caldera system erupted on the trailing edge of Eastern Gondwana between 325 and 295 Ma. Paleomagnetic samples were collected from ignimbrites and associated microgranitoid intrusions from the central, northern and southern calderas from which three components of magnetization are recognized. Component 1 is considered to be a viscous magnetization acquired during the Brunhes Chron. A presumed Permian component, C2, is found in seven paleomagnetic sites with a mean pole at 30.9°S, 139.7°E (K = 13.9, A95 = 16.8°, ASD = 21.7°), agreeing with previously reported Permian data from Australia. Carboniferous units have a well-defined characteristic component, C3, distinguished by dual polarity (predominantly reversed) and moderate to steep inclination directions. Paleomagnetic polarities in the Newcastle Range Volcanics are formation dependent and new constraints on the timing of Carboniferous volcanism (˜325-317 Ma) are consistent with recent reanalysis of the base of the Permo-Carboniferous Reversed Superchron (PCRS). A mean paleomagnetic pole, calculated from 15 VGPs, lies at 63.4°S, 125°E (K = 26.22, A95 = 7.6°, ASD = 15.8°), suggesting that Australia remained at midlatitudes into the Middle Carboniferous. This paleomagnetic pole is consistent with similarly aged poles from Western Gondwana, the conformity of which indicates contributions from nondipole components of the Earth's paleofield were probably not significant in the time immediately preceding the PCRS.

  7. The ancestral gene repertoire of animal stem cells. (United States)

    Alié, Alexandre; Hayashi, Tetsutaro; Sugimura, Itsuro; Manuel, Michaël; Sugano, Wakana; Mano, Akira; Satoh, Nori; Agata, Kiyokazu; Funayama, Noriko


    Stem cells are pivotal for development and tissue homeostasis of multicellular animals, and the quest for a gene toolkit associated with the emergence of stem cells in a common ancestor of all metazoans remains a major challenge for evolutionary biology. We reconstructed the conserved gene repertoire of animal stem cells by transcriptomic profiling of totipotent archeocytes in the demosponge Ephydatia fluviatilis and by tracing shared molecular signatures with flatworm and Hydra stem cells. Phylostratigraphy analyses indicated that most of these stem-cell genes predate animal origin, with only few metazoan innovations, notably including several partners of the Piwi machinery known to promote genome stability. The ancestral stem-cell transcriptome is strikingly poor in transcription factors. Instead, it is rich in RNA regulatory actors, including components of the "germ-line multipotency program" and many RNA-binding proteins known as critical regulators of mammalian embryonic stem cells.

  8. Global Alignment of Molecular Sequences via Ancestral State Reconstruction

    CERN Document Server

    Andoni, Alexandr; Hassidim, Avinatan; Roch, Sebastien


    Molecular phylogenetic techniques do not generally account for such common evolutionary events as site insertions and deletions (known as indels). Instead tree building algorithms and ancestral state inference procedures typically rely on substitution-only models of sequence evolution. In practice these methods are extended beyond this simplified setting with the use of heuristics that produce global alignments of the input sequences--an important problem which has no rigorous model-based solution. In this paper we consider a new version of the multiple sequence alignment in the context of stochastic indel models. More precisely, we introduce the following {\\em trace reconstruction problem on a tree} (TRPT): a binary sequence is broadcast through a tree channel where we allow substitutions, deletions, and insertions; we seek to reconstruct the original sequence from the sequences received at the leaves of the tree. We give a recursive procedure for this problem with strong reconstruction guarantees at low mut...

  9. Taphonomic analysis in lacustrine environments: Two different contexts for Triassic lake paleofloras from Western Gondwana (Argentina) (United States)

    Mancuso, Adriana Cecilia


    During the earliest Triassic several rift basins developed along the western margin of Gondwana associated with the pre-breakup of Pangea. They were filled by exclusively non-marine sediments including alluvial, fluvial, and lacustrine deposits. In the Ischigualasto-Villa Unión Basin, the lacustrine-deltaic succession is placed in the Los Rastros Formation and consists of several coarsening-upward cycles of black shale, siltstone, and sandstone. The paleontologic content of the succession includes abundant floral remains (related to the Dicroidium-type flora), invertebrates (conchostracans, insects), and vertebrates (fishes, a temnospondyl amphibian, ichnites). At the Cerro Puntudo area in the Cuyana Basin, the lacustrine succession forms the upper part of the Cerro Puntudo Formation and consists of limestone, stromatolitic limestone, mudstone, sandstone, and tuff. The paleontologic content includes scarce floral remains and rhizoliths; invertebrates are represented exclusively by traces (associated with ichnofacies of Skolithos and Scoyenia), and vertebrates by a fragment of the pelvic girdle of a basal arcosaur. The taphonomic analysis performed in the two Triassic lacustrine successions allows recognition of two different taphonomic histories for the plant remains. The Los Rastros lake preserved both autochthonous (originated in the littoral zone) and allochthonous (originated in the upstream fluvial system) elements. The offshore lacustrine area was dominated by autochthonous well-preserved elements and allochthonous plant debris and wood, which formed time-averaged accumulations. The delta deposits are characterized by allochthonous elements with varied preservational conditions, usually showing evidence of mechanical degradation and accumulation within a short time. Autochthonous and allochthonous material were preserved in the Los Rastros Lake by means of anoxic conditions in the offshore lacustrine area and high sedimentation rates in the delta. In

  10. Disintegration of the continental margin of northwestern Gondwana: Late Devonian of the eastern Anti-Atlas (Morocco) (United States)

    Wendt, Jobst


    The Devonian early Carboniferous sequence in the eastern Anti-Atlas represents a complete record of the last stage of the depositional and tectonic evolution along the northwestern margin of Gondwana. As a consequence of early Variscan block faulting, a platform and basin topography was established during the Middle and Late Devonian. Platforms were covered by condensed cephalopod limestones; sedimentation in the basins was mainly argillaceous with calcareous and turbiditic intercalations. In the latest Famennian/early Tournaisian the whole area was covered by delta deposits in the south passing into turbidites and olistostromes toward a continental slope farther north. This sedimentary and structural evolution reflects the gradual foundering and disintegration of the northwestern continental margin of Gondwana prior to the collisional stage in the late Visean/late Carboniferous.

  11. Paleomagnetic constraints on the Mesozoic drift of the Lhasa terrane (Tibet) from Gondwana to Eurasia (United States)

    Li, Zhenyu; Lippert, Peter; Ding, Lin; Song, Peiping; Yue, Yahui; van Hinsbergen, Douwe


    The Mesozoic plate tectonic history of Gondwana-derived crustal blocks of the Tibetan Plateau is hotly debated, but so far, paleomagnetic constraints quantifying their paleolatitudinal drift history remain sparse. Here, we compile existing data published mainly in Chinese literature and provide a new, high-quality, well-dated paleomagnetic pole from the ˜180 Ma Sangri Group volcanics of the Lhasa terrane. Our Sangri Group pole is calculated from pre-folding characteristic remanent magnetizations carried by thermoremanent magnetizations in low-Ti titanomagnetite and titanohematite in basalts and basaltic andesites that we have dated using zircon U-Pb geochronology. Forty-two lava sites (68%) meet our quality criteria and provide an average direction of D±ΔD = 341.9±3.4° , I±ΔI = -13.3±6.5° , A95 = 3.4, K = 42.9, n=42, corresponding to a paleolatitude of ˜6° S. The A95 value falls within the n-dependent confidence envelope of Deenen et al. (2011) (A95min=2.7; A95max=7.8), indicating that the data scatter can be straightforwardly explained by paleosecular variation of the paleomagnetic field alone. In addition, positive fold tests are consistent with a pre-folding remanence acquisition. Our new pole confirms a trend in existing data of variable quality that suggests the Lhasa terrane rifted from Gondwana in Late Triassic rather than Permian time, as widely perceived. A total northward drift of ˜ 4500 km between ˜220 and ˜130 Ma yields a reasonable average paleolatitudinal plate motion rate of 5 cm/yr. Our results are consistent with both an Indian or an Australian original position of the Lhasa terrane and cannot directly discriminate between these two interpretations. Nonetheless, we show that paleomagnetic data can provide a strong constraint on Mesozoic plate kinematics of the Tethyan realm. Our study also underscores the need for new, high-quality and well-dated paleomagnetic poles from the Paleozoic and Mesozoic of the Tibetan terranes.

  12. East Antarctic Rift Systems - key to understanding of Gondwana break-up (United States)

    Golynsky, D. A.; Golynsky, A. V.


    The results of analysis of radio-echo sounding surveys, the RADARSAT satellite data, magnetic and gravity information give evidence that East Antarctica contains 13 riftogenic systems and/or large linear tectonic structures. Among known and suggested rifts of East Antarctica the Lambert rift has a pivotal position and it manifests oneself as symmetry axis. Six additional systems are revealed on both sides of it and any one of them possesses special features in geologic and geomorphologic aspects. In most cases they inherited the anisotropy of long-lived cratonic blocks. Riftogenic and/or large linear tectonic structures along the East Antarctica coastal regions are distributed with a steady regularity with average distance between them about 650 km. For six (7) structures from 13 (Lambert, Jutulstraumen-Pencksökket, Vestfjella, Mellor-Slessor (Bailey), Wilkes Basin, Gaussberg (?) and Rennick) there is a distinct spatial coupling with trough complexes of the Beacon Supergroup and their subsequent reactivation in Late Jurassic - Permian time when the East Gondwana started break-up. Rift system of the Lambert-Amery Glaciers and Prydz Bay is related to Mesozoic extension events and it inherited structures of Paleozoic grabens. The total length of the rift system exceeds 4000 km of the same scale as largest the World rift belts. The length of the western branch of the Lambert rift that includes the Mellor rift and graben-like structures of the Bailey and Slessor glaciers exceeds 2300 km. Results of radio-echo sounding investigation of the subglacial Aurora Basin allow to suggest that this large basin of sub-meridian extension is underlain by an extensive (> 1000 km) riftogenic structure that is running towards the Transantarctic Mountains where it forms a triple junction with the eastern branch of the Lambert rift and structures of the Wilkes Basin. It is hereby proposed that Aurora-Scott rift is formed by complex system of sub-parallel depressions divided by

  13. Control of high velocity lithosphere roots on crustal scale density variations seen in Gondwana reconstructions (United States)

    Braitenberg, C. F.; Mariani, P.


    The GOCE gravity field is globally homogeneous at the resolution of about 80km or better allowing for the first time to identify tectonic structures at continental scale. The large scale structures are presumably controlled by the rheology of the underlying crust down to the base of the lithosphere. Seismic tomography identifies the presence of the deep lithosphere roots by increased velocity. The joint analysis of the tomography results and the GOCE gravity reveals that at global scale the two data have some common patterns. The correlations are enhanced by applying geodynamic plate reconstructions to the GOCE gravity field and to the tomography models which places today's observed fields at the Gondwana pre-breakup position. There are several examples for which it is found that the deep lithospheric roots, as those found below cratons, control the position of the positive gravity values outboard of the deep roots. This could be explained by the deep lithospheric roots focusing asthenospheric upwelling outboard of the root protecting the overlying craton from magmatic intrusions. Over several of the deep roots the gravity is systematically negative, which could be due to a compositional effect, with deep roots of increased velocity having reduced density. The study is carried out globally, with focus on the African and South American continents. The background for the study can be found in the following publications where the techniques which have been used are described: Braitenberg, C., Mariani, P. and De Min, A. (2013). The European Alps and nearby orogenic belts sensed by GOCE, Boll. Bollettino di Geofisica Teorica ed Applicata, 54(4), 321-334. doi:10.4430/bgta0105 Braitenberg, C. and Mariani, P. (2015). Geological implications from complete Gondwana GOCE-products reconstructions and link to lithospheric roots. Proceedings of 5th International GOCE User Workshop, 25 - 28 November 2014. Braitenberg, C. (2015). Exploration of tectonic structures with GOCE in

  14. Tectonic evolution of the Iberian margin of Gondwana and of correlative regions: A celebration of the career of Cecilio Quesada (United States)

    Murphy, J. Brendan; Nance, R. Damian; Johnston, Stephen T.


    This special issue celebrates the career of an exceptional geologist, Cecilio Quesada, an icon of Iberian geology who "retired" in 2014. It is an outcome of a symposium to honour Cecilio's career held in July 2014 in Madrid during the Gondwana 15 conference. The conference was hosted by the Instituto Geológico y Minero de España (IGME), Cecilio's employer since 1976.

  15. Estimation of the ancestral effective population sizes of African great apes under different selection regimes. (United States)

    Schrago, Carlos G


    Reliable estimates of ancestral effective population sizes are necessary to unveil the population-level phenomena that shaped the phylogeny and molecular evolution of the African great apes. Although several methods have previously been applied to infer ancestral effective population sizes, an analysis of the influence of the selective regime on the estimates of ancestral demography has not been thoroughly conducted. In this study, three independent data sets under different selective regimes were used were composed to tackle this issue. The results showed that selection had a significant impact on the estimates of ancestral effective population sizes of the African great apes. The inference of the ancestral demography of African great apes was affected by the selection regime. The effects, however, were not homogeneous along the ancestral populations of great apes. The effective population size of the ancestor of humans and chimpanzees was more impacted by the selection regime when compared to the same parameter in the ancestor of humans, chimpanzees and gorillas. Because the selection regime influenced the estimates of ancestral effective population size, it is reasonable to assume that a portion of the discrepancy found in previous studies that inferred the ancestral effective population size may be attributable to the differential action of selection on the genes sampled.

  16. Carboniferous granites on the northern margin of Gondwana, Anatolide-Tauride Block, Turkey - Evidence for southward subduction of Paleotethys (United States)

    Candan, O.; Akal, C.; Koralay, O. E.; Okay, A. I.; Oberhänsli, R.; Prelević, D.; Mertz-Kraus, R.


    Carboniferous metagranites with U-Pb zircon crystallization ages of 331-315 Ma crop out in the Afyon zone in the northern margin of the Anatolide-Tauride Block, which is commonly regarded as part of Gondwana during the Late Palaeozoic. They are peraluminous, calc-alkaline and are characterized by increase in Rb and Ba, decrease in Nb-Ta, and enrichment in Sr and high LILE/HFSE ratios compatible with a continental arc setting. The metagranites intrude a metasedimentary sequence of phyllite, metaquartzite and marble; both the Carboniferous metagranites and metasedimentary rocks are overlain unconformably by Lower Triassic metaconglomerates, metavolcanics and Upper Triassic to Cretaceous recrystallized limestones. The low-grade metamorphism and deformation occurred at the Cretaceous-Tertiary boundary. There is no evidence for Carboniferous deformation and metamorphism in the region. Carboniferous arc-type granites and previously described Carboniferous subduction-accretion complexes on the northern margin of the Anatolide-Tauride Block suggest southward subduction of Paleotethys under Gondwana during the Carboniferous. Considering the Variscan-related arc granites in Pelagonian and Sakarya zones on the active southern margin of Laurasia, a dual subduction of Paleotethys can be envisaged between Early Carboniferous and Late Permian. However, the southward subduction was short-lived and by the Late Permian the Gondwana margin became passive.

  17. Pull-apart origin of the Satpura Gondwana basin, central India

    Indian Academy of Sciences (India)

    Chandan Chakraborty; Sanjoy Kumar Ghosh


    The Gondwana basins of peninsular India are traditionally considered as extensional-rift basins due to the overwhelming evidence of fault-controlled synsedimentary subsidence. These basins indeed originated under a bulk extensional tectonic regime, due to failure of the attenuated crust along pre-existing zones of weakness inherited from Precambrian structural fabrics. However, disposition of the basins and their structural architecture indicate that the kinematics of all the basins cannot be extensional. To maintain kinematic compatibility with other basins as well as the bulk lateral extension, some basins ought to be of strike-slip origin. The disposition, shape and structural architecture of the Satpura basin, central India suggest that the basin could be a pull-apart basin that developed above a releasing jog of a left-stepping strike-slip fault system defined by the Son-Narmada south fault and Tapti north fault in consequence to sinistral displacement along WSW-ENE. Development of a sedimentary basin under the above-mentioned kinematic condition was simulated in model experiments with sandpack. The shape, relative size, stratigraphic and structural architecture of the experimental basin tally with that of the Satpura basin. The experimental results also provide insights into the tectono-sedimentary evolution of the Satpura basin in particular and pull-apart basins in general.

  18. A history of Proterozoic terranes in southern South America: From Rodinia to Gondwana

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    C. Casquet


    Full Text Available The role played by Paleoproterozoic cratons in southern South America from the Mesoproterozoic to the Early Cambrian is reconsidered here. This period involved protracted continental amalgamation that led to formation of the supercontinent Rodinia, followed by Neoproterozoic continental break-up, with the consequent opening of Clymene and Iapetus oceans, and finally continental re-assembly as Gondwana through complex oblique collisions in the Late Neoproterozoic to Early Cambrian. The evidence for this is based mainly on a combination of precise U-Pb SHRMP dating and radiogenic isotope data for igneous and metamorphic rocks from a large area extending from the Rio de la Plata craton in the east to the Argentine Precordillera in the west and as far north as Arequipa in Peru. Our interpretation of the paleogeographical and geodynamic evolution invokes a hypothetical Paleoproterozoic block (MARA embracing basement ultimately older than 1.7 Ga in the Western Sierras Pampeanas (Argentina, the Arequipa block (Peru, the Rio Apa block (Brazil, and probably also the Paraguaia block (Bolivia.

  19. CO 2 degassing and trapping during hydrothermal cycles related to Gondwana rifting in eastern Australia (United States)

    Uysal, I. Tonguç; Golding, Suzanne D.; Bolhar, Robert; Zhao, Jian-xin; Feng, Yue-xing; Baublys, Kim A.; Greig, Alan


    Intensive carbonate and clay mineral authigenesis took place throughout the Late Permian Bowen-Gunnedah-Sydney basin system in eastern Australia. We conducted isotopic and trace element analyses of carbonate and clay minerals from clastic sedimentary rocks of the Gunnedah Basin and the Denison Trough in the Bowen Basin. Rb-Sr isochron age data of the illitic clays are consistent with episodic hydrothermal fluid flow events that occurred in association with Gondwana rifting accompanied by alkaline magmatism at ˜85 Ma and ˜95 Ma. Stable isotope data of carbonate and clay minerals from the Gunnedah Basin are indicative of meteoric waters from a high-latitude environment as the main fluid source, whereas trace element, Sr and Nd isotope data highlight mixing of meteoric fluids with magmatic and/or crustal components, with a possible input from marine carbonates for some samples. Trace metals, oxygen and strontium isotopes of dawsonites from the Denison Trough are interpreted to have been mobilised by fluids that interacted with evolved clastic sedimentary and marine carbonate end members. According to the carbon isotope data, CO 2 for calcite and ankerite precipitation was sourced mainly from thermal degradation of organic matter and magmatism, whereas the CO 2 used for dawsonite formation is inferred to have been derived from magmatic and marine sources. In the low permeability environments (particularly in coal seams), the increasing accumulation and oversaturation of CO 2 particularly promote the precipitation of dawsonite.

  20. New Late Permian paleomagnetic data from Argentina: Refinement of the apparent polar wander path of Gondwana (United States)

    Domeier, Mathew; van der Voo, Rob; Tohver, Eric; Tomezzoli, Renata N.; Vizan, Haroldo; Torsvik, Trond H.; Kirshner, Jordan


    The Late Paleozoic-Early Mesozoic apparent polar wander path of Gondwana is largely constructed from relatively old paleomagnetic results, many of which are considered unreliable by modern standards. Paleomagnetic results derived from sedimentary sequences, which are generally poorly dated and prone to inclination shallowing, are especially common. Here we report the results of a joint paleomagnetic-geochronologic study of a volcanic complex in central Argentina. U-Pb dating of zircons has yielded a robust age estimate of 263.0 +1.6/-2.0 Ma for the complex. Paleomagnetic analysis has revealed a pretilting (primary Permian) magnetization with dual polarities. Rock magnetic experiments have identified pseudo-single domain (titano)magnetite and hematite as the mineralogic carriers of the magnetization. Lightning-induced isothermal remagnetizations are widespread in the low-coercivity magnetic carriers. The resulting paleomagnetic pole is 80.1°S, 349.0°E, A95 = 3.3°, N = 35, and it improves a Late Permian mean pole calculated from a filtered South American paleomagnetic data set. More broadly, this new, high-quality, igneous-based paleomagnetic pole falls between the previously distinct Late Permian segments of the Laurussian and Gondwanan apparent polar wander paths, suggesting that the long-recognized disparity between these large paleomagnetic data sets may be primarily due to the inclusion of low-quality or systemically biased data.

  1. EVOLUTION. A four-legged snake from the Early Cretaceous of Gondwana. (United States)

    Martill, David M; Tischlinger, Helmut; Longrich, Nicholas R


    Snakes are a remarkably diverse and successful group today, but their evolutionary origins are obscure. The discovery of snakes with two legs has shed light on the transition from lizards to snakes, but no snake has been described with four limbs, and the ecology of early snakes is poorly known. We describe a four-limbed snake from the Early Cretaceous (Aptian) Crato Formation of Brazil. The snake has a serpentiform body plan with an elongate trunk, short tail, and large ventral scales suggesting characteristic serpentine locomotion, yet retains small prehensile limbs. Skull and body proportions as well as reduced neural spines indicate fossorial adaptation, suggesting that snakes evolved from burrowing rather than marine ancestors. Hooked teeth, an intramandibular joint, a flexible spine capable of constricting prey, and the presence of vertebrate remains in the guts indicate that this species preyed on vertebrates and that snakes made the transition to carnivory early in their history. The structure of the limbs suggests that they were adapted for grasping, either to seize prey or as claspers during mating. Together with a diverse fauna of basal snakes from the Cretaceous of South America, Africa, and India, this snake suggests that crown Serpentes originated in Gondwana.

  2. Allatotropin: An Ancestral Myotropic Neuropeptide Involved in Feeding (United States)

    Alzugaray, María Eugenia; Adami, Mariana Laura; Diambra, Luis Anibal; Hernandez-Martinez, Salvador; Damborenea, Cristina; Noriega, Fernando Gabriel; Ronderos, Jorge Rafael


    Background Cell-cell interactions are a basic principle for the organization of tissues and organs allowing them to perform integrated functions and to organize themselves spatially and temporally. Peptidic molecules secreted by neurons and epithelial cells play fundamental roles in cell-cell interactions, acting as local neuromodulators, neurohormones, as well as endocrine and paracrine messengers. Allatotropin (AT) is a neuropeptide originally described as a regulator of Juvenile Hormone synthesis, which plays multiple neural, endocrine and myoactive roles in insects and other organisms. Methods A combination of immunohistochemistry using AT-antibodies and AT-Qdot nanocrystal conjugates was used to identify immunoreactive nerve cells containing the peptide and epithelial-muscular cells targeted by AT in Hydra plagiodesmica. Physiological assays using AT and AT- antibodies revealed that while AT stimulated the extrusion of the hypostome in a dose-response fashion in starved hydroids, the activity of hypostome in hydroids challenged with food was blocked by treatments with different doses of AT-antibodies. Conclusions AT antibodies immunolabeled nerve cells in the stalk, pedal disc, tentacles and hypostome. AT-Qdot conjugates recognized epithelial-muscular cell in the same tissues, suggesting the existence of anatomical and functional relationships between these two cell populations. Physiological assays indicated that the AT-like peptide is facilitating food ingestion. Significance Immunochemical, physiological and bioinformatics evidence advocates that AT is an ancestral neuropeptide involved in myoregulatory activities associated with meal ingestion and digestion. PMID:24143240

  3. Inference of Ancestral Recombination Graphs through Topological Data Analysis. (United States)

    Cámara, Pablo G; Levine, Arnold J; Rabadán, Raúl


    The recent explosion of genomic data has underscored the need for interpretable and comprehensive analyses that can capture complex phylogenetic relationships within and across species. Recombination, reassortment and horizontal gene transfer constitute examples of pervasive biological phenomena that cannot be captured by tree-like representations. Starting from hundreds of genomes, we are interested in the reconstruction of potential evolutionary histories leading to the observed data. Ancestral recombination graphs represent potential histories that explicitly accommodate recombination and mutation events across orthologous genomes. However, they are computationally costly to reconstruct, usually being infeasible for more than few tens of genomes. Recently, Topological Data Analysis (TDA) methods have been proposed as robust and scalable methods that can capture the genetic scale and frequency of recombination. We build upon previous TDA developments for detecting and quantifying recombination, and present a novel framework that can be applied to hundreds of genomes and can be interpreted in terms of minimal histories of mutation and recombination events, quantifying the scales and identifying the genomic locations of recombinations. We implement this framework in a software package, called TARGet, and apply it to several examples, including small migration between different populations, human recombination, and horizontal evolution in finches inhabiting the Galápagos Islands.

  4. Deep phylogeny, ancestral groups and the four ages of life. (United States)

    Cavalier-Smith, Thomas


    Organismal phylogeny depends on cell division, stasis, mutational divergence, cell mergers (by sex or symbiogenesis), lateral gene transfer and death. The tree of life is a useful metaphor for organismal genealogical history provided we recognize that branches sometimes fuse. Hennigian cladistics emphasizes only lineage splitting, ignoring most other major phylogenetic processes. Though methodologically useful it has been conceptually confusing and harmed taxonomy, especially in mistakenly opposing ancestral (paraphyletic) taxa. The history of life involved about 10 really major innovations in cell structure. In membrane topology, there were five successive kinds of cell: (i) negibacteria, with two bounding membranes, (ii) unibacteria, with one bounding and no internal membranes, (iii) eukaryotes with endomembranes and mitochondria, (iv) plants with chloroplasts and (v) finally, chromists with plastids inside the rough endoplasmic reticulum. Membrane chemistry divides negibacteria into the more advanced Glycobacteria (e.g. Cyanobacteria and Proteobacteria) with outer membrane lipolysaccharide and primitive Eobacteria without lipopolysaccharide (deserving intenser study). It also divides unibacteria into posibacteria, ancestors of eukaryotes, and archaebacteria-the sisters (not ancestors) of eukaryotes and the youngest bacterial phylum. Anaerobic eobacteria, oxygenic cyanobacteria, desiccation-resistant posibacteria and finally neomura (eukaryotes plus archaebacteria) successively transformed Earth. Accidents and organizational constraints are as important as adaptiveness in body plan evolution.

  5. Ancestral TSH mechanism signals summer in a photoperiodic mammal. (United States)

    Hanon, Elodie A; Lincoln, Gerald A; Fustin, Jean-Michel; Dardente, Hugues; Masson-Pévet, Mireille; Morgan, Peter J; Hazlerigg, David G


    In mammals, day-length-sensitive (photoperiodic) seasonal breeding cycles depend on the pineal hormone melatonin, which modulates secretion of reproductive hormones by the anterior pituitary gland [1]. It is thought that melatonin acts in the hypothalamus to control reproduction through the release of neurosecretory signals into the pituitary portal blood supply, where they act on pituitary endocrine cells [2]. Contrastingly, we show here that during the reproductive response of Soay sheep exposed to summer day lengths, the reverse applies: Melatonin acts directly on anterior-pituitary cells, and these then relay the photoperiodic message back into the hypothalamus to control neuroendocrine output. The switch to long days causes melatonin-responsive cells in the pars tuberalis (PT) of the anterior pituitary to increase production of thyrotrophin (TSH). This acts locally on TSH-receptor-expressing cells in the adjacent mediobasal hypothalamus, leading to increased expression of type II thyroid hormone deiodinase (DIO2). DIO2 initiates the summer response by increasing hypothalamic tri-iodothyronine (T3) levels. These data and recent findings in quail [3] indicate that the TSH-expressing cells of the PT play an ancestral role in seasonal reproductive control in vertebrates. In mammals this provides the missing link between the pineal melatonin signal and thyroid-dependent seasonal biology.

  6. The microcephalin ancestral allele in a Neanderthal individual.

    Directory of Open Access Journals (Sweden)

    Martina Lari

    Full Text Available BACKGROUND: The high frequency (around 0.70 worldwide and the relatively young age (between 14,000 and 62,000 years of a derived group of haplotypes, haplogroup D, at the microcephalin (MCPH1 locus led to the proposal that haplogroup D originated in a human lineage that separated from modern humans >1 million years ago, evolved under strong positive selection, and passed into the human gene pool by an episode of admixture circa 37,000 years ago. The geographic distribution of haplogroup D, with marked differences between Africa and Eurasia, suggested that the archaic human form admixing with anatomically modern humans might have been Neanderthal. METHODOLOGY/PRINCIPAL FINDINGS: Here we report the first PCR amplification and high-throughput sequencing of nuclear DNA at the microcephalin (MCPH1 locus from Neanderthal individual from Mezzena Rockshelter (Monti Lessini, Italy. We show that a well-preserved Neanderthal fossil dated at approximately 50,000 years B.P., was homozygous for the ancestral, non-D, allele. The high yield of Neanderthal mtDNA sequences of the studied specimen, the pattern of nucleotide misincorporation among sequences consistent with post-mortem DNA damage and an accurate control of the MCPH1 alleles in all personnel that manipulated the sample, make it extremely unlikely that this result might reflect modern DNA contamination. CONCLUSIONS/SIGNIFICANCE: The MCPH1 genotype of the Monti Lessini (MLS Neanderthal does not prove that there was no interbreeding between anatomically archaic and modern humans in Europe, but certainly shows that speculations on a possible Neanderthal origin of what is now the most common MCPH1 haplogroup are not supported by empirical evidence from ancient DNA.

  7. The Korarchaeota: Archaeal orphans representing an ancestral lineage of life

    Energy Technology Data Exchange (ETDEWEB)

    Elkins, James G.; Kunin, Victor; Anderson, Iain; Barry, Kerrie; Goltsman, Eugene; Lapidus, Alla; Hedlund, Brian; Hugenholtz, Phil; Kyrpides, Nikos; Graham, David; Keller, Martin; Wanner, Gerhard; Richardson, Paul; Stetter, Karl O.


    Based on conserved cellular properties, all life on Earth can be grouped into different phyla which belong to the primary domains Bacteria, Archaea, and Eukarya. However, tracing back their evolutionary relationships has been impeded by horizontal gene transfer and gene loss. Within the Archaea, the kingdoms Crenarchaeota and Euryarchaeota exhibit a profound divergence. In order to elucidate the evolution of these two major kingdoms, representatives of more deeply diverged lineages would be required. Based on their environmental small subunit ribosomal (ss RNA) sequences, the Korarchaeota had been originally suggested to have an ancestral relationship to all known Archaea although this assessment has been refuted. Here we describe the cultivation and initial characterization of the first member of the Korarchaeota, highly unusual, ultrathin filamentous cells about 0.16 {micro}m in diameter. A complete genome sequence obtained from enrichment cultures revealed an unprecedented combination of signature genes which were thought to be characteristic of either the Crenarchaeota, Euryarchaeota, or Eukarya. Cell division appears to be mediated through a FtsZ-dependent mechanism which is highly conserved throughout the Bacteria and Euryarchaeota. An rpb8 subunit of the DNA-dependent RNA polymerase was identified which is absent from other Archaea and has been described as a eukaryotic signature gene. In addition, the representative organism possesses a ribosome structure typical for members of the Crenarchaeota. Based on its gene complement, this lineage likely diverged near the separation of the two major kingdoms of Archaea. Further investigations of these unique organisms may shed additional light onto the evolution of extant life.

  8. Reconstructing the ancestral butterfly eye: focus on the opsins. (United States)

    Briscoe, Adriana D


    The eyes of butterflies are remarkable, because they are nearly as diverse as the colors of wings. Much of eye diversity can be traced to alterations in the number, spectral properties and spatial distribution of the visual pigments. Visual pigments are light-sensitive molecules composed of an opsin protein and a chromophore. Most butterflies have eyes that contain visual pigments with a wavelength of peak absorbance, lambda(max), in the ultraviolet (UV, 300-400 nm), blue (B, 400-500 nm) and long wavelength (LW, 500-600 nm) part of the visible light spectrum, respectively, encoded by distinct UV, B and LW opsin genes. In the compound eye of butterflies, each individual ommatidium is composed of nine photoreceptor cells (R1-9) that generally express only one opsin mRNA per cell, although in some butterfly eyes there are ommatidial subtypes in which two opsins are co-expressed in the same photoreceptor cell. Based on a phylogenetic analysis of opsin cDNAs from the five butterfly families, Papilionidae, Pieridae, Nymphalidae, Lycaenidae and Riodinidae, and comparative analysis of opsin gene expression patterns from four of the five families, I propose a model for the patterning of the ancestral butterfly eye that is most closely aligned with the nymphalid eye. The R1 and R2 cells of the main retina expressed UV-UV-, UV-B- or B-B-absorbing visual pigments while the R3-9 cells expressed a LW-absorbing visual pigment. Visual systems of existing butterflies then underwent an adaptive expansion based on lineage-specific B and LW opsin gene multiplications and on alterations in the spatial expression of opsins within the eye. Understanding the molecular sophistication of butterfly eye complexity is a challenge that, if met, has broad biological implications.

  9. Proterozoic Tectonic History of Borborema Province, NE Brazil: Implications For Assembly of West Gondwana (United States)

    van Schmus, W. R.; Brito Neves, B. B.

    The Borborema Province of NE Brazil comprises the west-central part of a wide Pan- African - Brasiliano continental collision belt that formed during ca. 600 Ma assembly of West Gondwana. Our studies over the past decade, in collaboration with many other workers, demonstrate a complex Proterozoic history that created or modified crustal domains at 2.1, 1.7, 1.0, 0.8, and 0.6 Ga. Although NE Brazil contains a few small Archean domains included within early Paleoproterozoic orogens, the first major event was formation of extensive continental crust about 2.35 to 2.1 Ga, before and during the so-called Transamazonian orogeny. We believe that this occurred in conjunction with formation of a larger Paleoproterozoic continent about 2.05 Ga that included present-day West African, Amazonian, Congo, and São Francisco cratons. Incipient extension within this continent occurred in Brazil about 1.8 to 1.7 Ga, resulting in intracratonic sedimentation and bimodal volcanism, but equivalent rocks are less well known in Africa. A successful breakup occurred before or about 1.1 Ga, resulting in separation of parts of this continent into two major stable masses containing (a) the Amazon-West African craton, and (b) the São Francisco-Congo (SF/C) craton. The break-up also created many smaller fragments between these two large masses, particularly in the east (present-day NE Brazil and Saharan Africa) and including the Ceará-Rio Grande do Norte (CE/RN) craton in NE Brazil. About 1.0 Ga a magmatic arc more than 700 km long (Cariris Velhos orogen) developed in NE Brazil, possibly as a result of convergence between the CE/RN and SF/C cratons; eastward extension of the 1.0 Ga Cariris Velhos orogen into West Africa is presently unknown. About 850 to 700 Ma several extensional basins developed in NE Brazil, with intraplate bimodal volcanism and clastic sedimentation; coeval basins may have formed in west-central Africa. From 700 to 600 Ma plate convergence among the CE/RN craton, SF

  10. Early to mid Cretaceous vegetation of northern Gondwana - the onset of angiosperm radiation and climatic implications (United States)

    Coiffard, Clément; Mohr, Barbara


    Early Cretaceous Northern Gondwana seems to be the cradle of many early flowering plants, especially mesangiosperms that include magnoliids and monocots and basal eudicots. So far our knowledge was based mostly on dispersed pollen and small flowering structures. New fossil finds from Brazil include more complete plants with attached roots, leaves and flowers. Taxonomic studies show that these fossils belonged to clades which are, based on macroscopic characters and molecular data, also considered to be rather basal, such as several members of Nymphaeales, Piperales, Laurales, Magnoliales, monocots (Araliaceae) and Ranunculales. Various parameters can be used in order to understand the physiology and habitat of these plants. Adaptations to climate and habitat are partly mirrored in their root anatomy (evidence of tap roots), leaf size and shape, leaf anatomy including presence of glands, and distribution of stomata. An important ecophysiolocical parameter is vein density as an indicator for the plants' cabability to pump water, and the stomatal pore index, representing the proportion of stomatal pore area on the leaf surface, which is related to the water vapor resistance of the leaf epidermis. During the mid-Cretaceous leaf vein density started to surpass that of gymnosperms, one factor that made angiosperms very successful in conquering many kinds of new environments. Using data on these parameters we deduce that during the late Early to mid Cretaceous angiosperms were already diverse, being represented as both herbs, with aquatic members, such as Nymphaeles, helophytes (e.g. some monocots) and plants that may have grown in shady locations. Other life forms included shrubs and perhaps already small trees (e.g. Magnoliales). These flowering plants occupied various habitats, ranging from xeric (e.g. some Magnoliales) to mesic and shady (e.g. Piperales) or aquatic (e.g. Araceae, Nymphaeales). Overall, it seems that several of these plants clearly exhibited some

  11. A new Cretaceous terrestrial ecosystem from Gondwana with the description of a new sauropod dinosaur

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    Jorge O. Calvo


    Full Text Available A unique site at the northern area of Patagonia (Neuquén, Argentina reveals a terrestrial ecosystem preserved in a detail never reported before in a Late Cretaceous deposit. An extraordinary diversity and abundance of fossils was found concentrated in a 0.5 m horizon in the same quarry, including a new titanosaur sauropod, Futalognkosaurus dukei n.gen., n.sp, which is the most complete giant dinosaur known so far. Several plant leaves, showing a predominance of angiosperms over gymnosperms that likely constituted the diet of F. dukei were found too. Other dinosaurs (sauropods, theropods, ornithopods, crocodylomorphs, pterosaurs, and fishes were also discovered, allowing a partial reconstruction of this Gondwanan continental ecosystem.Um depósito fóssil na região norte da Patagônia (Neuquén, Argentina revela um ecossistema nunca antes registrado a este nível de detalhes em depósitos do Cretáceo Superior. Uma diversidade e abundância extraordinária de fósseis encontra-se concentrada em uma camada de 0,5 m no mesmo sítio, incluindo um novo saurópodo titanossaurídeo, Futalognkosaurus dukei n. gen, n. sp., que é o mais completo dinossauro gigante encontrado até a presente data. Foram descobertas váriasfolhas de plantas indicando a predominância de angiospermas sobre gimnospermas que possivelmente formavam a base da dieta de F. dukei. Outros dinossauros (saurópodes, terópodes, ornitópodes, crocodilomorfos, pterossauros e peixes foram também encontrados possibilitando a reconstrução parcialdeste ecossistema continental do Gondwana.

  12. Permian-Triassic Magmatism Along the Southern Gondwana Margin: Correlating Proximal and Distal Volcanic Deposits (United States)

    McKay, M. P.; Weislogel, A. L.; Fildani, A.


    Active margins are dominated by erosion, structural deformation, tectonic dissection, and igneous intrusions. These destructive processes lead to an incomplete record of past magmatism in active margins. Volcanic airfall tuffs that are transported and deposited in distal sedimentary basins may be more likely to be preserved in the rock record. Tuffs, however, may be affected by atmospheric fractionation during transport, postdepositional weathering, and diagenesis during burial, potentially altering ash texture, mineralogy, and geochemistry. We use outcrop observations, stratigraphic relationships, whole rock geochemistry, U-Pb zircon geochronology, and zircon rare-earth element geochemistry from Permian-Triassic strata of South Africa and South America to correlate distal volcanic ashes to proximal volcanic deposits and plutonic suites within southern Gondwana. U-Pb zircon signals of the tuffs are treated as "detrital"; the distinct zircon signals were then used to correlate distal airfall ashes to potential magmatic sources. This suggests that airfall fractionation of zircon populations is not a significant concern in tuff geochronology. Additionally, zircon inheritance may be a useful tool in matching far-traveled ashes with parental magmatic suites. Although previous studies have shown that the geochemistry of volcanic tuff deposits varies with distance from the volcanic vent, we employ whole rock and zircon REE compositions to differentiate distinct magmatic periods using distal ashes that were deposited >750 km from the volcanic source. The results of this study support a geochronologic interpretation that the Karoo strata of S. Africa are >10 Ma younger than previously thought based on biostratigraphy. Since the Karoo basin is heavily studied as a record of the end-Permian extinction and paleoclimate change, our results have major implication for this key time in Earth History.

  13. Sedimentary history of the Tethyan margins of Eastern Gondwana during the Mesozoic (United States)

    Ogg, James G.; Gradstein, Felix M.; Dumoulin, Julie A.; Sarti, Massimo; Bown, Paul

    A composite Mesozoic geological history for the Gondwana margins to the Eastern Tethys Ocean can be assembled from stratigraphic successions on the Australian and Himalayan margins and from drill sites of Ocean Drilling Program Legs 122 and 123. During the Triassic, this region drifted northwards, entering tropical paleolatitudes during the Late Triassic-Early Jurassic, then returned to mid-latitudes for the Middle Jurassic through Early Cretaceous. Shallow-water carbonates are restricted to the tropical-latitude interval; at other times, the margins are dominated by clastic deposition. Episodes of deltaic sandstone progradation over the shelves are caused by eustatic sealevel fluctuations, by wet climatic conditions within the source regions and by local tectonic activity. A major hiatus between Callovian shallow-water shelf deposits and Oxfordian deep-water sediments is an ubiquitous feature, which may be related to a widespread plate tectonic reorganization and the cascading effects of associated sealevel rise and elevated carbon dioxide levels. Off Northwest Australia, this Callovian/Oxfordian event also coincides with an episode of block faulting. Marginal sediments deposited during the Late Jurassic are mainly marine claystone containing abundant terrigenous organic matter. Shallow depths of carbonate compensation (CCD) during the Late Jurassic through Early Cretaceous prevented the preservation of carbonate over most of the Argo basin off Northwest Australia, and these deep-sea sediments consist mainly of condensed, oxygenated radiolarian-rich claystone. During the late Kimmeridgian-early Tithonian, a downward excursion in the CCD enabled limited preservation of some larger nannofossils and mollusc fragments within the pelagic deposits, a feature also recorded in coeval deposits in the Atlantic. Explosive volcanism accompanied the final stages of rifting between India and Australia during the late Berriasian and Valanginian, producing volcaniclastic debris

  14. Tectonostratigraphic terranes of the frontier circum-Pacific region

    Energy Technology Data Exchange (ETDEWEB)

    Howell, D.G.; Jones, D.L.; Schermer, E.R.


    Many major exploration frontiers around the Pacific are in regions where complex geologic relations reflect plate-tectonic processes, crustal mobility, and accretion of exotic terranes. The destruction of the proto-Pacific ocean (Panthalassa) involved accretion of terranes to cratonal regions such as Gondwana and Laurasia. Terranes in southwestern New Zealand and eastern Antarctica were also probably accreted during the Paleozoic. The southern margin of Siberia, extending into China, underwent a protracted period of accretion from the late Precambrian through the early Mesozoic. Mid-Paleozoic accretion is reflected in the Innuitian foldbelt of the Arctic Ocean, the Black Clastic unit of the northern Rocky Mountains, and the Antler orogeny of the western US cordillera. The Mesozoic breakup of Pangaea and the acceleration of subduction aided in the rifting and dispersal of terranes from equatorial paleolatitudes. Fragments of these terranes now compose much of the continental margins of the Pacific basin, including New Zealand, Indochina, southern China, southeast Siberia, the North American cordillera, and South America. Some terranes are presently being further fragmented by post-accretionary dispersion processes such as strike-slip faulting in western North America and Japan. Although the character and distribution of terranes in the western US are fairly well documented, details are needed for other terranes around the Pacific basin. Interpretation of structure and stratigraphy at depth will be aided by more data on the timing of accretion and the nature of deformation associated with accretion and dispersion. Such data are needed for further define specific exploration targets in the circum-Pacific region.

  15. From northern Gondwana passive margin to arc dismantling: a geochemical discrimination of Ordovician volcanisms (Sardinia, Italy) (United States)

    Gaggero, L.; Oggiano, G.; Buzzi, L.; Funedda, A.


    In Sardinia, one of the southernmost remain of the European Variscan belt, a crustal section through northern Gondwanan paleodomains is largely preserved. It bears significant evidence of igneous activity, recently detailed in field relationships and radiometric dating (Oggiano et al., submitted). A Cambro - Ordovician (491.7 ± 3.5 Ma ÷ 479.9 ± 2.1 Ma, LA-ICP-MS U-Pb zircon age) bimodal volcanic suite occurs with continuity in external and inner Variscan nappes of Sardinia below the so-called Sardic unconformity. The igneous suite represents an intraplate volcanic activity developed through subsequent episodes: i) an intermediate explosive and effusive volcanism, i.e. pyroclastic fall deposits and lava flows, embedded into epicontinental clastic sediments, culminating in silicic ignimbrite eruptions, and ii) mafic effusives. Geochemical data document a transitional, within-plate signature, e.g. the average Th/Ta (4.5) and La/Nb (2.7) overlap the upper continental crust values. The volcanites are characterized by slight fractionation of LREEs, nearly flat HREE abundance. The negative Eu anomaly increases towards evolved compositions. Some prominent HREE depletion (GdCN/YbCN = 13.8), and the high Nb/Y suggest a garnet-bearing source. The high 87Sr radiogenic content (87Sr/86Sr 490 Ma = 0.71169) and the epsilon Nd 490 Ma value of -6.54 for one dacite sample, imply a time integrated LREE-enriched source with a high Rb/Sr, such as a metasedimentary source. The stratigraphy of the succession and the geochemical composition of igneous members suggest a volcanic passive margin along the northern Gondwana at the early Ordovician. The bimodal Mid-Ordovician arc volcanism (465.4 ± 1.4 Ma, U-Pb zircon age; Oggiano et al., submitted) is developed in the external nappes (e.g. in Sarrabus and Sarcidano) and in the foreland occurs as clasts at the base of the Hirnantian succession (Leone et al. 1991). The Mid Ordovician sub-alkalic volcanic suite has reliable stratigraphic and

  16. An ancestral role for the mitochondrial pyruvate carrier in glucose-stimulated insulin secretion

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    Kyle S. McCommis


    Conclusions: Altogether, these studies suggest that the MPC plays an important and ancestral role in insulin-secreting cells in mediating glucose sensing, regulating insulin secretion, and controlling systemic glycemia.

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

    Institute of Scientific and Technical Information of China (English)

    Thierry Smith; Kishor Kumar; Rajendra S. Rana; Annelise Folie; Floréal Solé; Corentin Noiret; Thomas Steeman; Ashok Sahni; Kenneth D. Rose


    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 Cor-yphodon-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, dyr-osaurids, 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 ep-isodes of contact between the Indian subcontinent and different island blocks along the northern margin of the Neotethys, such as the KohistaneLadakh 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 dispersals would have

  18. The eoorthid brachiopod Apheoorthina in the Lower Ordovician of NW Argentina and the dispersal pathways along western Gondwana

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    Diego F. Muñoz


    Full Text Available The eoorthid brachiopod Apheoorthina is reported for the first time from the Lower Ordovician of NW Argentina. It is represented by a species similar to A. ferrigena from the Tremadocian of the Prague Basin, increasing the faunal affinities between the Central Andean Basin and the South European microcontinents, in particular the Bohemian region (Perunica. Nine out of the fourteen brachiopod genera reported from the Tremadocian of the Central Andean Basin (~64% are shared with the Mediterranean region, four of which (~28% have been recorded in the Prague Basin, and two (Kvania and Apheoorthina are restricted to the Central Andes and Perunica. Dispersal pathways around Gondwana are analyzed in the light of major factors affecting large-scale distribution of brachiopods (environment, larval capacity for dispersal, oceanic currents. The presence in Apheoorthina aff. ferrigena of a well-preserved larval protegulum measuring 420 μm in width and 210 μm in length strongly suggests that this species had planktotrophic larvae capable of long-distance dispersal. According to recent ocean-atmosphere general circulation models for the Ordovician Period, the Central Andean margin was dominated by the cold-water Antarctica Current. Despite the complex non-zonal pattern produced by current deflections around the peri-Gondwanan microcontinents, the general westward circulation sense favoured larval dispersal from the Andean region to North Africa, Avalonia, the Armorican Terrane Assemblage, and Perunica. On the other hand, the eastwards flowing Gondwana Current connected the North Gondwana waters with the South American epicontinental seas, which could explain the reversed migration of some brachiopods.

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

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    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

  20. Analysis of the stone ancestral hall of Guo’s tomb on Xiaotang mountainin Han dynasty architectural features

    Institute of Scientific and Technical Information of China (English)



    The stone ancestral hall of Guo’s tomb in Xiaotang mountain is the earliest existing buildings on the ground in China. It has a very high historical, cultural and artistic value, and it was described by the ancient and modern scholars and experts in their books and articles. But the study of architectural of ancestral hall was emphasized from 1930s, and became a brilliant star in the Chinese historic buildings. In this article, the architectural characteristics of the stone ancestral hall are discussed through fieldworks, in order to clarify the real architecture appearance of the ancestral hall and refer more informations for comprehensive study of Xiaotang stone ancestral hall.

  1. Widely divergent transcriptional patterns between SLE patients of different ancestral backgrounds in sorted immune cell populations. (United States)

    Sharma, Shruti; Jin, Zhongbo; Rosenzweig, Elizabeth; Rao, Swapna; Ko, Kichul; Niewold, Timothy B


    Systemic lupus erythematosus (SLE) is a complex autoimmune disease of uncertain etiology. Patients from different ancestral backgrounds demonstrate differences in clinical manifestations and autoantibody profiles. We examined genome-wide transcriptional patterns in major immune cell subsets across different ancestral backgrounds. Peripheral blood was collected from African-American (AA) and European-American (EA) SLE patients and controls. CD4 T-cells, CD8 T-cells, monocytes, and B cells were purified by flow sorting, and each cell subset from each subject was run on a genome-wide expression array. Cases were compared to controls of the same ancestral background. The overlap in differentially expressed gene (DEG) lists between different cell types from the same ancestral background was modest (type between different ancestral backgrounds. IFN-stimulated gene (ISG) expression was not up-regulated synchronously in all cell types from a given patient, for example a given subject could have high ISG expression in T and B cells, but not in monocytes. AA subjects demonstrated more concordance in ISG expression between cell types from the same individual, and AA patients demonstrated significant down-regulation of metabolic gene expression which was not observed in EA patients. ISG expression was significantly decreased in B cells in patients taking immunosuppressants, while ISGs in other cell types did not differ with medication use. In conclusion, gene expression was strikingly different between immune cell subsets and between ancestral backgrounds in SLE patients. These findings emphasize the critical importance of studying multiple ancestral backgrounds and multiple cell types in gene expression studies. Ancestral backgrounds which are not studied will not benefit from personalized medicine strategies in SLE.

  2. First report of the Gondwana genus Beatogordius from India, with further records of two Chordodes species (Gordiida, Nematomorpha) (United States)

    Yadav, Arun K.; Schmidt-Rhaesa, Andreas; Limatemjen


    Abstract Three horsehair worms (Nematomorpha) are recorded from Nagaland, India. The first species is Chordodes combiareolatus, which was recently described from Nagaland. The second is Chordodes cf. furnessi, earlier reported from Meghalaya, and some new observations are added. The third is a new species, described as Beatogordius nagalandis sp. n. This is the first report of the genus Beatogordius in India and this observation fits well into the Gondwana distribution of the genus. The species is quite similar to Beatogordius chinensis, reported from South China. PMID:28144175

  3. The survival effect in memory: does it hold into old age and non-ancestral scenarios? (United States)

    Yang, Lixia; Lau, Karen P L; Truong, Linda


    The survival effect in memory refers to the memory enhancement for materials encoded in reference to a survival scenario compared to those encoded in reference to a control scenario or with other encoding strategies. The current study examined whether this effect is well maintained in old age by testing young (ages 18-29) and older adults (ages 65-87) on the survival effect in memory for words encoded in ancestral and/or non-ancestral modern survival scenarios relative to a non-survival control scenario. A pilot study was conducted to select the best matched comparison scenarios based on potential confounding variables, such as valence and arousal. Experiment 1 assessed the survival effect with a well-matched negative control scenario in both young and older adults. The results showed an age-equivalent survival effect across an ancestral and a non-ancestral modern survival scenario. Experiment 2 replicated the survival effect in both age groups with a positive control scenario. Taken together, the data suggest a robust survival effect that is well preserved in old age across ancestral and non-ancestral survival scenarios.

  4. Paleozoic Orogens of Mexico and the Laurentia-Gondwana Connections: an Update (United States)

    Ortega-Gutierrez, F.


    The present position of Mexico in North America and the fixist tectonic models that prevailed prior to the seventies of the past century, have considered the main Paleozoic tectonic systems of Mexico as natural extensions of the orogens that fringed the eastern and southern sides of the Laurentian craton. Well known examples of pre-Mesozoic orogens in Mexico are the Oaxacan, Acatlan, and Chiapas polymetamorphic terranes, which have been correlated respectively with the Grenville and Appalachian-Ouachitan orogens of eastern North America. Nonetheless, several studies conducted during the last decade in these Mexican orogenic belts, have questioned their Laurentian connections, regarding northwestern Gondwana instead as the most plausible place for their birth and further tectonic evolution. This work pretends to approach the problem by briefly integrating the massive amount of new geological information, commonly generated through powerful dating methods such as LA-ICPM-MS on detrital zircon of sedimentary and metasedimentary units in the Paleozoic crustal blocks, which are widely exposed in southern and southeastern Mexico. The Acatlan Complex bears the closest relationships to the Appalachian orogenic system because it shows thermotectonic evidence for opening and closure of the two main oceans involved in building the Appalachian mountains in eastern Laurentia, whereas two other Paleozoic terranes in NW and SE Mexico, until recently rather geologically unknown, may constitute fundamental links between the Americas for the last-stage suturing and consolidation of western Pangea. The buried basement of the Yucatan platform (400,000 squared km) on the other hand, remains as one of the most relevant problems of tectonostratigraphic correlations across the Americas, because basement clasts from the Chicxulub impact ejecta reveal absolute and Nd-model ages that suggest close Gondwanan affinities. Major changes in the comprehension of the Paleozoic orogens in Mexico

  5. Is the Palaeozoic of Istanbul a part of Gondwana-Land or Laurasia, or both? (United States)

    Lom, Nalan; Ülgen, Semih Can; Özgül, Necdet; Celal Şengör, A. M.


    The Istanbul Zone, northwestern Turkey, located along the southwestern Black Sea coast, consists of a Neoproterozoic (almost entirely Ediacaran) middle to high-grade crystalline basement with relicts of oceanic lithosphere, volcanic arc and continental crust of unknown affinity and it is overlain by a continuous, well-developed transgressive sedimentary sequence extending from the late Ordovician to the Carboniferous. The Palaeozoic sequence was folded and thrust-faulted during the Carboniferous Hercynian orogeny, and is unconformably overlain by Lower Triassic and younger sedimentary strata. The Istanbul Zone is separated from the Sakarya Zone by the Intra- Pontide suture of early to medial Eocene and from the Strandja Massif by an inferred right-lateral strike-slip West Black Sea Fault. The Sakarya and Strandja fragments exhibit late Triassic and late Jurassic-Early Cretaceous metamorphism and deformation, respectively, which are not observed in the Istanbul Zone. The Palaeozoic sequences of Istanbul and Zonguldak have been compared and correlated with similar sequences in Europe, including the Moesian platform in Romania and Bulgaria, Moravo-Silesia (Brunovistulian) in the Czech Republic and the Rhenohercynian zone in Germany and Belgium, all deposited on the northern passive margin of the Rheic ocean. However, these correlations are based on insufficient knowledge of the correlated rock sequences. By contrast, the İstanbul sequence resembles the Carnic Alps, the Montaigne Noir, the Bohemian (Saxo-Thuringian), the Morocco, the Pyrenean sequences and thus northern Gondwana-Land of the Palaeozoic times. Istanbul Zone thus combines the characteristics of both the north and south Hercynian margins! The Istanbul Zone shows characteristics of graben-facies deposits during the Ordovician-early Silurian followed by Atlantic-type continental margin sediments of late Silurian- late Devonian age. Since the arc is missing, the ocean facing İstanbul must have been consumed

  6. Ancient plate kinematics derived from the deformation pattern of continental crust: Paleo- and Neo-Tethys opening coeval with prolonged Gondwana-Laurussia convergence (United States)

    Kroner, Uwe; Roscher, Marco; Romer, Rolf L.


    The formation and destruction of supercontinents requires prolonged convergent tectonics between particular plates, followed by intra-continental extension during subsequent breakup stages. A specific feature of the Late Paleozoic supercontinent Pangea is the prolonged and diachronous formation of the collisional belts of the Rheic suture zone coeval with recurrent continental breakup and subsequent formation of the mid-ocean ridge systems of the Paleo- and Neo-Tethys oceans at the Devonian and Permian margins of the Gondwana plate, respectively. To decide whether these processes are causally related or not, it is necessary to accurately reconstruct the plate motion of Gondwana relative to Laurussia. Here we propose that the strain pattern preserved in the continental crust can be used for the reconstruction of ancient plate kinematics. We present Euler pole locations for the three fundamental stages of the Late Paleozoic assembly of Pangea and closure of the Rheic Ocean: (I) Early Devonian (ca. 400 Ma) collisional tectonics affected Gondwana at the Armorican Spur north of western Africa and at the promontory of the South China block/Australia of eastern Gondwana, resulting in the Variscan and the Qinling orogenies, respectively. The Euler pole of the rotational axis between Gondwana and Laurussia is positioned east of Gondwana close to Australia. (II) Continued subduction of the western Rheic Ocean initiates the clockwise rotation of Gondwana that is responsible for the separation of the South China block from Gondwana and the opening of Paleo-Tethys during the Late Devonian. The position of the rotational axis north of Africa reveals a shift of the Euler pole to the west. (III) The terminal closure of the Rheic Ocean resulted in the final tectonics of the Alleghanides, the Mauritanides and the Ouachita-Sonora-Marathon belt, occurred after the cessation of the Variscan orogeny in Central Europe, and is coeval with the formation of the Central European Extensional

  7. Evidence of Gondwana early rifting process recorded by Resende-Ilha Grande Dike Swarm, southern Rio de Janeiro, Brazil (United States)

    Guedes, Eliane; Heilbron, Monica; de Morisson Valeriano, Claudio; de Almeida, Julio César Horta; Szatmari, Peter


    Continental flood basalts and dike swarm have been related to continental breakup process through geological time. The Resende - Ilha Grande Dike swarm (RIGDS) located in the southeast Brazil, is related the Gondwana breakup and composed of dikes/sills intruded in Precambrian gneiss. The dikes have three distinguish orientations: NNW more inland; NS-NNE in the central segment and NE orientation in the coast line, consistent with Precambrian structural lineaments. The swarm comprises high-TiO2 tholeiitic basalts divided into three suites based on REE and Sr and Nd isotope data. The Resende and Volta Redonda suites present higher initial 87Sr/86Sr ratios between 0.7077 and 0.7065, while Angra dos Reis suite presents values of 0.7066 to 0.7057. Geochemical and isotopic data support the sub-continental lithospheric mantle (SCLM) as the main source for the high-TiO2 basalts. The suites heterogeneities are explained by different compositions of SCLM in accreted Precambrian terranes and/or different degree of partial melting and fractional. 40Ar/39Ar data indicate age interval between ca. 156 to 144 Ma for the swarm, older than the average for Gondwana breakup (ca. 130-120 Ma). The age interval places the RIGDS between the Karoo magmatism (181-178 Ma) and the Paraná-Etendeka magmatism (133-134 Ma) and indicates that extensional process affected the supercontinent prior the break-up.

  8. The Mesozoic Continental Magmatism in Brazil: its Role in the Western Gondwana Evolution from Integrated Paleomagnetic and Geochemical Data (United States)

    Ernesto, M.; Marques, L. S.


    Most of the Paleozoic era in the South American platform represents a period of tectonic quiescence during which large sedimentary basins evolved. Subsequently an intense magmatic activity took place preceding the disclosure of the Gondwana from Pangea, and later the disruption of the western Gondwana blocks (South America and Africa separation). In Brazil Early Jurassic (~220-180 Ma) tholeiitic basalts erupted mostly in the northern area (Amazonas and Parnaíba basins), whereas the Early Cretaceous (~140-120 Ma) is best represented by the huge magmatism of the Serra Geral Formation (Paraná basin, southeastern Brazil). An intense associated intrusive activity in the form of dykes and sills of both ages is widespread all over the country but tends to concentrate towards the continental margins. The integration of paleomagnetic and geochemical data on the Brazilian Mesozoic magmatism put some constraints on the timing, duration and the mantle sources involved in the generation of the magma products related to the different magmatic events.

  9. The Cordon del Portillo Permian magmatism, Mendoza, Argentina, plutonic and volcanic sequences at the western margin of Gondwana (United States)

    Gregori, Daniel; Benedini, Leonardo


    The Cerro Punta Blanca, Cerro Bayo and Cerro Punta Negra stocks, parts of the Cordillera Frontal Composite Batholith, cropping out in the Cordón del Portillo, records the Gondwana magmatic development of the Cordillera Frontal of Mendoza, in western Argentina. In this area, the San Rafael Orogenic phase, that represents the closure of the Late Carboniferous-Early Permian marine basins, begins at 284 Ma, and ceased before 276 Ma. The Cerro Punta Blanca, Cerro Bayo and Cerro Punta Negra stocks represent a post-orogenic magmatism and are equivalents to the Choiyoi Group. The Gondwana magmatic activity in the Cordón del Portillo area can be divided into two stages. The Cerro Punta Blanca stock (c.a. 276 Ma) represents an early post-orogenic, subduction-related magmatism similar to the basic-intermediate section of the Choiyoi Group (c.a. 277 Ma). The late post-orogenic second event was recorded by the Cerro Bayo (262 Ma) and Cerro Punta Negra stocks which represent a transition between subduction-related and intra-plate magmatism. This event represents the intrusive counterpart of the acidic facies of the upper section of the Choiyoi Group (c.a. 273 Ma). This extensional condition continued during the Triassic when the Cacheuta basin developed.

  10. Isotopic (U-Pb, Nd) and geochemical constraints on the origins of the Aileu and Gondwana sequences of Timor (United States)

    Boger, S. D.; Spelbrink, L. G.; Lee, R. I.; Sandiford, M.; Maas, R.; Woodhead, J. D.


    Detrital zircon U-Pb age data collected from the argillitic sedimentary rocks of the Timorese Aileu Complex and Gondwana Sequence indicate that both units were derived from a common source containing 200-600 Ma, 900-1250 Ma and 1450-1900 Ma zircon. The modally most significant age population within this range of ages dates to c. 260 Ma. The observed spectrum of ages can be traced to the eastern active margin of Pangaea and its immediate foreland, which today is best exposed along the northeast coast of Australia. Compared to the relative homogeneity of the detrital zircon age data, geochemical and Nd isotopic data show that the mudstones of the Aileu Complex are on average more siliceous, have higher K2O/Na2O, Rb/Sr, Th/Sc and yield notably older Nd TDM model ages when compared to those from the Gondwana Sequence. These data are interpreted to suggest that, although both sequences share a common east Pangaea provenance, they were eroded from different sections of this active margin and deposited in spatially separated basins. The present proximity of these units is a result of their tectonic juxtaposition during the Pliocene to Recent collision between the northern edge of the Indo-Australia plate and the Banda Arc.

  11. Tectonic subsidence modelling and Gondwana source rock hydrocarbon potential, Northwest Bangladesh modelling of Kuchma, Singra and Hazipur wells

    Energy Technology Data Exchange (ETDEWEB)

    Frielingsdorf, J. [Shell Petroleum Development Company, Nigeria Limited, P.O. Box 23, Port Harcourt, Rivers State (Nigeria); Aminul Islam, Sk.; Mizanur Rahman, Md. [BAPEX, Bangladesh Petroleum Exploration and Production Ltd., Shahjalal Tower, 80/A-B Siddeshwari Circular Road, Dhaka 1217 (Bangladesh); Block, Martin [Federal Institute for Geosciences and Natural Resources (BGR), Stilleweg 2, 30655 Hannover (Germany); Golam Rabbani, Md. [Norwegian University of Science and Technology (NTNU), 7491 Trondheim (Norway)


    The northwestern part of Bangladesh is in terms of hydrocarbon exploration still under-explored. This paper presents the basin development from a structural point of view and includes the results of thermal and maturity modelling using numerical tools of basin modelling. One regional seismic section and three exploration wells have been investigated to unravel a conceptual model for the subsidence and thermal history of the region. According to the findings it is very likely that up to 2900 m of Triassic/Jurassic and partly Permian sediments have been eroded prior to the break-up of Gondwana. During continental break-up a peak heat flow is considered. This was necessary for calibrating maturity profiles using vitrinite reflectance (VR) derived from modelled wells. A significant gas generation phase during Lower Jurassic is predicted. At modelled well locations, although renewed subsidence occurred during Tertiary to present day, a second phase of gas generation has not occurred, as past maximum temperatures were not exceeded. According to the interpreted regional seismic sections in the region, the area southeast of the 'Hinge Zone' can be regarded as the main kitchen area for gas generation from the Gondwana source rock. The petroleum system in the northwestern part of Bangladesh remains high risk due to uncertainties in source rock distribution and generation. (author)

  12. Petrologic, tectonic, and metallogenic evolution of the Ancestral Cascades magmatic arc, Washington, Oregon, and northern California (United States)

    du Bray, Edward A.; John, David A.


    Present-day High Cascades arc magmatism was preceded by ~40 m.y. of nearly cospatial magmatism represented by the ancestral Cascades arc in Washington, Oregon, and northernmost California (United States). Time-space-composition relations for the ancestral Cascades arc have been synthesized from a recent compilation of more than 4000 geochemical analyses and associated age data. Neither the composition nor distribution of ancestral Cascades magmatism was uniform along the length of the ancestral arc through time. Initial (>40 to 36 Ma) ancestral Cascades magmatism (mostly basalt and basaltic andesite) was focused at the north end of the arc between the present-day locations of Mount Rainier and the Columbia River. From 35 to 18 Ma, initial basaltic andesite and andesite magmatism evolved to include dacite and rhyolite; magmatic activity became more voluminous and extended along most of the arc. Between 17 and 8 Ma, magmatism was focused along the part of the arc coincident with the northern two-thirds of Oregon and returned to more mafic compositions. Subsequent ancestral Cascades magmatism was dominated by basaltic andesite to basalt prior to the post–4 Ma onset of High Cascades magmatism. Transitional tholeiitic to calc-alkaline compositions dominated early (before 40 to ca. 25 Ma) ancestral Cascades eruptive products, whereas the majority of the younger arc rocks have a calc-alkaline affinity. Tholeiitic compositions characteristic of the oldest ancestral arc magmas suggest development associated with thin, immature crust and slab window processes, whereas the younger, calc-alkaline magmas suggest interaction with thicker, more evolved crust and more conventional subduction-related magmatic processes. Presumed changes in subducted slab dip through time also correlate with fundamental magma composition variation. The predominance of mafic compositions during latest ancestral arc magmatism and throughout the history of modern High Cascades magmatism probably

  13. A Cambrian Arc Built on the Neoproterozoic Rifted Margin of Gondwana (United States)

    Musgrave, R. J.


    Cambrian convergence along the northeastern side of the Curnamona Craton, the Gondwana margin in southeastern Australia, resulted in the development of the Delamerian Orogen. A Neoproterozoic rifted margin, marked by the alkalic Mount Arrowsmith Volcanics, forms the substrate on which is built a NE-facing Cambrian arc, complete with a clearly delineated inner imbricate accretionary prism (the Wonnaminta Zone) and outer thin-skinned wedge (the Kayrunnera Zone). Arc volcanism, represented by the calc-alkaline Mount Wright Volcanics, exhibits mixed arc-rift geochemistry. Interpretation and modelling of magnetic data reveals a chain of volcanic edifices of the Mount Wright Arc, now below 3 to 7 km of Devonian sandstones in the Bancannia Trough. Remarkably, a simple rotation around an Euler pole reconstructs the Wonnaminta Zone against the craton, and aligns structural elements on the two sides of the trough. Arc volcanism evidently occupied a rift in marginal continental crust, and the geometry, geochemistry and geophysical properties of the Mount Wright Arc are closely analogous to the Taupo Zone of New Zealand. Rifting of the arc divided Delamerian structures, indicating that at least part of the Delamerian deformation developed in a subduction accretion setting, rather than in some terminal collision. Below the Wonnaminta Zone a 3 to 5 km thick body can be traced as a large magnetic source along the length of the zone. Overridden by the thrust stack of the accretionary prism, this body is mostly planar and dips towards the east, although it is deformed into a broad antiform in the central part of the zone. Physical properties suggest that this body may be a thick rift-volcanic pile equivalent to the Mount Arrowsmith Volcanics. In the southern part of the belt a re-entrant in the Wonnaminta Zone faces a large magnetic anomaly sourced in the basement of the Kayrunnera Zone. The geometry of the re-entrant, and the development of Silurian and Devonian basins over the

  14. Pacific Flyway management plan for Pacific brant (United States)

    US Fish and Wildlife Service, Department of the Interior — The Pacific Flyway brant (Branta bernicla) population (PFBP) is made up of brant breeding in Alaska, the western Canadian arctic, and the eastern Russian arctic, and...

  15. Common 5' beta-globin RFLP haplotypes harbour a surprising level of ancestral sequence mosaicism. (United States)

    Webster, Matthew T; Clegg, John B; Harding, Rosalind M


    Blocks of linkage disequilibrium (LD) in the human genome represent segments of ancestral chromosomes. To investigate the relationship between LD and genealogy, we analysed diversity associated with restriction fragment length polymorphism (RFLP) haplotypes of the 5' beta-globin gene complex. Genealogical analyses were based on sequence alleles that spanned a 12.2-kb interval, covering 3.1 kb around the psibeta gene and 6.2 kb of the delta-globin gene and its 5' flanking sequence known as the R/T region. Diversity was sampled from a Kenyan Luo population where recent malarial selection has contributed to substantial LD. A single common sequence allele spanning the 12.2-kb interval exclusively identified the ancestral chromosome bearing the "Bantu" beta(s) (sickle-cell) RFLP haplotype. Other common 5' RFLP haplotypes comprised interspersed segments from multiple ancestral chromosomes. Nucleotide diversity was similar between psibeta and R/T-delta-globin but was non-uniformly distributed within the R/T-delta-globin region. High diversity associated with the 5' R/T identified two ancestral lineages that probably date back more than 2 million years. Within this genealogy, variation has been introduced into the 3' R/T by gene conversion from other ancestral chromosomes. Diversity in delta-globin was found to lead through parts of the main genealogy but to coalesce in a more recent ancestor. The well-known recombination hotspot is clearly restricted to the region 3' of delta-globin. Our analyses show that, whereas one common haplotype in a block of high LD represents a long segment from a single ancestral chromosome, others are mosaics of short segments from multiple ancestors related in genealogies of unsuspected complexity.

  16. Which came first: The lizard or the egg? Robustness in phylogenetic reconstruction of ancestral states. (United States)

    Wright, April M; Lyons, Kathleen M; Brandley, Matthew C; Hillis, David M


    Changes in parity mode between egg-laying (oviparity) and live-bearing (viviparity) have occurred repeatedly throughout vertebrate evolution. Oviparity is the ancestral amniote state, and viviparity has evolved many times independently within amniotes (especially in lizards and snakes), with possibly a few reversions to oviparity. In amniotes, the shelled egg is considered a complex structure that is unlikely to re-evolve if lost (i.e., it is an example of Dollo's Principle). However, a recent ancestral state reconstruction analysis concluded that viviparity was the ancestral state of squamate reptiles (lizards and snakes), and that oviparity re-evolved from viviparity many times throughout the evolutionary history of squamates. Here, we re-evaluate support for this provocative conclusion by testing the sensitivity of the analysis to model assumptions and estimates of squamate phylogeny. We found that the models and methods used for parity mode reconstruction are highly sensitive to the specific estimate of phylogeny used, and that the point estimate of phylogeny used to suggest that viviparity is the root state of the squamate tree is far from an optimal phylogenetic solution. The ancestral state reconstructions are also highly sensitive to model choice and specific values of model parameters. A method that is designed to account for biases in taxon sampling actually accentuates, rather than lessens, those biases with respect to ancestral state reconstructions. In contrast to recent conclusions from the same data set, we find that ancestral state reconstruction analyses provide highly equivocal support for the number and direction of transitions between oviparity and viviparity in squamates. Moreover, the reconstructions of ancestral parity state are highly dependent on the assumptions of each model. We conclude that the common ancestor of squamates was oviparous, and subsequent evolutionary transitions to viviparity were common, but reversals to oviparity were

  17. Sedimentary facies and depositional environments related to Gondwana glaciation in Batovi and Suspiro regions, Rio Grande Do Sul, Brazil (United States)

    Tomazelli, Luiz José; Soliani, Enio


    Sedimentary facies were produced by Late Paleozoic Gondwana ice sheets in the Batovi and Suspiro regions, Rio Grande do Sul State, southern Brazil. The glaciogenic sediments, assigned to the Itararé Group of Paraná Basin, are the result of processes related to the subglacial, supraglacial and proglacial (ice-contact, glaciofluvial and glaciolacustrine) environments of the glacial depositional system. Several features developed by the action of glaciers were identified in the studied outcrops: striated and grooved pavements; striated, polished and faceted stones; finely laminated rhythmites bearing dropstones (varvites); erratic clasts and deposits exhibiting deformational structures such as folds, normal and reverse faults, and beds with abnormal dips. The available evidence suggests that the glacial episodes took place in a terrestrial (continental) context, far from direct marine influence.

  18. New Rb-Sr mineral ages temporally link plume events with accretion at the margin of Gondwana (United States)

    Flowerdew, M.J.; Daly, J.S.; Riley, T.R.


    Five of six Rb-Sr muscovite mineral isochron ages from the Scotia Metamorphic Complex of the South Orkney Islands, West Antarctica, average 190 ± 4 Ma. The muscovite ages are interpreted to date foliation-formation and thus also accretion and subduction at the Gondwana margin. Coincident picrite and ferropicrite magmatism, indicative of melts from deep-seated depleted mantle, permits a causative link between accretion and the arrival of the Karoo – Ferrar – Chon Aike mantle plume in the Early Jurassic. Three biotite Rb-Sr mineral isochron ages are consistently younger and average 176 ± 5 Ma. The biotite ages may record post-metamorphic cooling or more likely retrogressive metamorphic effects during uplift.

  19. Carbon isotope chemostratigraphy of the Llandovery in northern peri-Gondwana: new data from the Barrandian area, Czech Republic

    Directory of Open Access Journals (Sweden)

    Jiří Frýda


    Full Text Available The first complete δ13Corg record of the uppermost Hirnantian to lower Telychian strata of the Barrandian area (northern peri-Gondwana is presented based on 168 new samples. The new data from the study area reveal that the evolution of the Llandoverian organic carbon isotope reservoir was similar to that on other palaeoplates, but it differs from the development of the coeval carbonate carbon isotope reservoir in the absence of two δ13C excursions (i.e. the early Aeronian positive excursion in the upper part of the Demirastrites triangulatus graptolite Biozone and a negative excursion occurring close to the boundary between the Cystograptus vesiculosus and Coronograptus cyphus graptolite biozones.

  20. Cryptic signatures of Neoproterozoic accretionary events in northeast Brazil imaged by magnetotellurics: Implications for the assembly of West Gondwana (United States)

    Padilha, Antonio L.; Vitorello, Icaro; Pádua, Marcelo B.; Fuck, Reinhardt A.


    The Borborema Province, in northeast Brazil, is a complex orogenic system severely affected by deformational, metamorphic, and magmatic processes mostly during the Gondwana convergence in late Neoproterozoic-early Phanerozoic Brasiliano/Pan-African Orogeny. New magnetotelluric (MT) data collected along the northwestern part of the province and eastern part of the contiguous Parnaíba Basin are combined with previous MT data to assess the regional deep electrical resistivity structure. Dimensionality analysis shows that a 3D electrical structure predominates in the subsurface and thus 3D inversion was carried out. The final geoelectric model allows delineating the geometry and variation in physical properties of different lithospheric blocks bounded by major electrical discontinuities. These lithospheric blocks constitute a coalesced mosaic made up of four main terrane compartments: a resistive cratonic keel detected along the western part of the study area, currently hidden beneath the Parnaíba Basin (Parnaíba block); two complex domains in the center characterized by several resistive and conductive zones throughout the crust and upper mantle (Ceará Central and Rio Grande do Norte domains); and a conductive block in the east, with the geoelectric response being controlled by possible remains of late Neoproterozoic subduction activity to the south (Central sub-province). The interfaces between these blocks are interpreted as suture zones correlated to their Neoproterozoic collage, one curved conductor concealed by the sediments of the Parnaíba Basin and bordering the eastern margin of the basin, another huge conductor corresponding to the location of the Orós-Jaguaribe subdomain on the surface, and a third interface coinciding with the position of the Patos shear zone. The presence of these proposed sutures could be a conspicuous evidence of a Neoproterozoic accretion system in northeast Brazil and would support tectonic evolution models for the West Gondwana

  1. Mesozoic lacustrine system in the Parnaíba Basin, northeastern Brazil: Paleogeographic implications for west Gondwana (United States)

    Cardoso, Alexandre Ribeiro; Nogueira, Afonso César Rodrigues; Abrantes, Francisco Romério; Rabelo, Cleber Eduardo Neri


    The fragmentation of the West Gondwana during Early Triassic to Cretaceous was marked by intense climatic changes, concomitant with the establishment of extensive desertic/lacustrine systems. These deposits succeeded the emplacement and extrusion of lava flows, related to the pre-rift phase and initial opening of the Equatorial Atlantic Ocean. The thermal phase is recorded in the Upper Jurassic-Lower Cretaceous Pastos Bons Formation, exposed mainly in southeast parts of the Parnaíba Basin, Northeastern Brazil. The sedimentary facies of this unit were grouped in two facies associations (FA), representative of a shallow lacustrine system, influenced by episodic hyperpycnal and oscillatory flows. Central lake facies association (FA1) is composed by laminated mudstone (Ml), sandstone/mudstone rhythmite (S/Mr) and sandstone with even-parallel lamination (Sel). Flysch-like delta front (FA2) consists in sandstones with wave structures (Sw), sandstones with even-parallel stratification (Ses), massive sandstones (Sm), sandstones with soft-sediment deformation structures (Sd) and laminated mudstones (Ml). FA1 was deposited in the deepest portions of the lake, characterized by low energy, episodically disturbed by siliciclastic influx. FA2 presents sandy deposits generated by unconfined flow, probably fed by ephemeral stream flows that generated thickening upward of tabular sandstone beds. The progressive filling of the lake resulted in recurrent shoaling up of the water level and reworking by wave action. The installation of Pastos Bons lakes was controlled by thermal subsidence, mainly in restricted depocenters. The siliciclastic fluvial inflow can be related to the adjacent humid desertic facies, formed under climatic attenuation, typical of post-Triassic period, with reduced biological activity. Smectite and abundant feldspars, in lacustrine facies, corroborate an arid climate, with incipient chemical weathering. The new facies and stratigraphic data present in this

  2. Early Paleozoic accretionary orogenesis along northern margin of Gondwana constrained by high-Mg metaigneous rocks, SW Yunnan (United States)

    Xing, Xiaowan; Wang, Yuejun; Cawood, Peter A.; Zhang, Yuzhi


    SW Yunnan of China constituted part of the northern margin of Gondwana facing the proto-Tethys ocean in the early Paleozoic. However, the evolution of the region and its relationship with the accretionary orogenism have been poorly established. This paper reports a set of new zircon U-Pb age data and whole-rock major oxides, elemental and Sr-Nd isotopic data for early Paleozoic metavolcanic rocks from the previously defined Lancang Group and reveals the development of an Ordovician suprasubduction zone in SW Yunnan. Zircon U-Pb ages of 462 ± 6 and 454 ± 27 Ma for two representative samples indicate eruption of the volcanic rocks in the Late Ordovician. Geochemical data for the metavolcanic rocks together with other available data indicate a calc-alkaline affinity with high Al2O3 (13.04-18.77 wt%) and low TiO2 (0.64-1.00 wt%). They have Mg-numbers ranging from 62 to 50 with SiO2 of 53.57-69.10 wt%, compositionally corresponding to the high-Mg andesitic rocks. They display enrichments in LREEs and LILEs with significant Eu negative anomalies (δEu = 0.20-0.33), and depletions in HFSEs, similar to arc volcanic rocks. Their initial 87Sr/86Sr ratios range from 0.721356 to 0.722521 and ɛNd(t) values from -7.63 to -7.62 with Nd model ages of 2.06-2.10 Ga. Integration of ages and geochemical data with available geological observations, we propose the presence of Ordovician magmatism related to proto-Tethyan evolution in SW Yunnan and the metaigneous rocks formed in an island-arc setting. They were part of a regional accretionary orogen that extended along the northern margin of Gondwana during Neoproterozoic to early Paleozoic period.

  3. Inheritance of the 8.1 ancestral haplotype in recurrent pregnancy loss

    DEFF Research Database (Denmark)

    Kolte, Astrid M; Nielsen, Henriette S; Steffensen, Rudi;


    BACKGROUND AND OBJECTIVES: The 8.1 ancestral haplotype (AH) (HLA-A1, C7, B8, C4AQ0, C4B1, DR3, DQ2) is a remarkably long and conserved haplotype in the human major histocompatibility complex. It has been associated with both beneficial and detrimental effects, consistent with antagonistic pleiotr...

  4. Language Shift and Maintenance in Multilingual Mauritius: The Case of Indian Ancestral Languages (United States)

    Bissoonauth, Anu


    This paper reports on a research study conducted in Mauritius between June and July 2009. The aim of this research was to investigate the use of Indian ancestral languages in the domestic domain by the younger generations. The data were collected in the field by means of a questionnaire and interviews from a quota sample of secondary school…

  5. Ancestral TCDD exposure promotes epigenetic transgenerational inheritance of imprinted gene Igf2: Methylation status and DNMTs. (United States)

    Ma, Jing; Chen, Xi; Liu, Yanan; Xie, Qunhui; Sun, Yawen; Chen, Jingshan; Leng, Ling; Yan, Huan; Zhao, Bin; Tang, Naijun


    Ancestral TCDD exposure could induce epigenetic transgenerational phenotypes, which may be mediated in part by imprinted gene inheritance. The aim of our study was to evaluate the transgenerational effects of ancestral TCDD exposure on the imprinted gene insulin-like growth factor-2 (Igf2) in rat somatic tissue. TCDD was administered daily by oral gavage to groups of F0 pregnant SD rats at dose levels of 0 (control), 200 or 800 ng/kg bw during gestation day 8-14. Animal transgenerational model of ancestral exposure to TCDD was carefully built, avoiding sibling inbreeding. Hepatic Igf2 expression of the TCDD male progeny was decreased concomitantly with hepatic damage and increased activities of serum hepatic enzymes both in the F1 and F3 generation. Imprinted Control Region (ICR) of Igf2 manifested a hypermethylated pattern, whereas methylation status in the Differentially Methylated Region 2 (DMR2) showed a hypomethylated manner in the F1 generation. These epigenetic alterations in these two regions maintained similar trends in the F3 generation. Meanwhile, the expressions of DNA methyltransferases (DNMT1, DNMT3A and DNMT3B) changed in a non-monotonic manner both in the F1 and F3 generation. This study provides evidence that ancestral TCDD exposure may promote epigenetic transgenerational alterations of imprinted gene Igf2 in adult somatic tissue.

  6. Assessing the prediction fidelity of ancestral reconstruction by a library approach. (United States)

    Bar-Rogovsky, Hagit; Stern, Adi; Penn, Osnat; Kobl, Iris; Pupko, Tal; Tawfik, Dan S


    Ancestral reconstruction is a powerful tool for studying protein evolution as well as for protein design and engineering. However, in many positions alternative predictions with relatively high marginal probabilities exist, and thus the prediction comprises an ensemble of near-ancestor sequences that relate to the historical ancestor. The ancestral phenotype should therefore be explored for the entire ensemble, rather than for the sequence comprising the most probable amino acid at all positions [the most probable ancestor (mpa)]. To this end, we constructed libraries that sample ensembles of near-ancestor sequences. Specifically, we identified positions where alternatively predicted amino acids are likely to affect the ancestor's structure and/or function. Using the serum paraoxonases (PONs) enzyme family as a test case, we constructed libraries that combinatorially sample these alternatives. We next characterized these libraries, reflecting the vertebrate and mammalian PON ancestors. We found that the mpa of vertebrate PONs represented only one out of many different enzymatic phenotypes displayed by its ensemble. The mammalian ancestral library, however, exhibited a homogeneous phenotype that was well represented by the mpa. Our library design strategy that samples near-ancestor ensembles at potentially critical positions therefore provides a systematic way of examining the robustness of inferred ancestral phenotypes.


    Energy Technology Data Exchange (ETDEWEB)

    Lesperance, Ann M.; Matlock, Gordon W.; Becker-Dippmann, Angela S.; Smith, Karen S.


    On March 26, 2013, the Snohomish County Public Utility District (PUD) and the U.S. Department of Energy’s (DOE’s) Pacific Northwest National Laboratory (PNNL) jointly hosted the Pacific Northwest Cyber Summit with the DOE’s Office of Electricity Delivery and Energy Reliability, the White House, Washington State congressional delegation, Washington State National Guard, and regional energy companies.

  8. Evidence of pre-Gondwana tectono-thermal event from the Bhilwara Supracrustal units of Rajasthan, north-west India (United States)

    Saha, Lopamudra; Sarkar, Saheli; Rakshit, Nibedita; Nasipuri, Pritam


    In the Indian subcontinent, two pre- Gondwana (pre- Pan African) orogenies are mostly recorded and well-studied from the Eastern Ghat Mobile Belt: (i) >1.1 Ga and (ii) ~950 Ma. During the ~950Ma orogeny, the pre-existing granulites have been re-melted under granulite facies conditions at ~8 kbar, 800-850ºC in the sillimanite stability field with formation of garnet-orthopyroxene in the restites. In this study we report garnet-sillimanite bearing and garnet-staurolite-kyanite bearing supracrustal rocks from the Bhilwara Supergroup in Rajasthan, N-W India. Peak assemblage in the garnet-sillimanite bearing metapelite is: garnet-sillimanite-biotite-plagioclase-quartz. Garnet porphyroblasts contain sillimanite-biotite bearing inclusion trails. Matrix foliations consist of biotite, sillimanite, quartz. Peak pressure-temperature calculated for garnet formation are ~7-8 kbar, 800ºC. Garnet is replaced along the margins by biotite during retrogression. Within garnet-staurolite-kyanite schist, peak assemblage is formed of garnet-staurolite-biotite-kyanite quartz, where garnet and staurolite occur as porphyroclasts and the matrix foliations are formed of kyanite-biotite-quartz. Mineral assemblages and compositions in the rock indicate peak pressure-temperature >8 kbar, 600ºC. The ages of the metamorphic events at sillimanite and kyanite facies are not well-constrained. However since the Bhilwara supracrustal units occur close to the Grenvillian orogenic belt at Sandmata Complex, the timing of the peak metamorphism can be constrained at ~1.0 Ga. Garnet-sillimanite-bearing assemblages noted in the Bhilwara Supracrustal Belt, has also been noted from the Grenvillian belts in the Eastern Ghat Mobile Belt. So the question that needs to be addressed is whether the Grenvillian orogenic belt recorded form the Sandmata Complex in Rajasthan and that of the Eastern Ghat Belt had been a continuous orogenic belt? Such possibilities can be addressed by establishing detailed structural

  9. Shallow lacustrine system of the Permian Pedra de Fogo Formation, Western Gondwana, Parnaíba Basin, Brazil (United States)

    Araújo, Raphael Neto; Nogueira, Afonso César Rodrigues; Bandeira, José; Angélica, Rômulo Simões


    The Permian Period of the Parnaíba Basin, northern Brazil, represented here by deposits from the Pedra de Fogo Formation, records important events that occurred in Western Gondwana near its boundary with the Mesozoic Era. The analysis of outcrop based facies from the Permian Pedra de Fogo Formation, which is 100 m thick, carried out along the eastern and western borders of the Parnaiba Basin, allowed the identification of eleven sedimentary facies, which were grouped into three distinct facies associations (FA), representative of a shallow lacustrine system associated with mudflats and ephemeral rivers. Bioturbation, desiccation cracks, silcretes and various siliceous concretions characterize the Pedra de Fogo deposits. The FA1 mudflat deposits occur predominantly at the base of the Pedra de Fogo Formation and consist of laminated claystone/mudstone, mudcrack-bearing sandstones/mudstones and sandstones exhibiting cross-lamination, massive and megaripple bedding. Popcorn-like silicified nodules and casts indicate evaporite deposits. Other common features are silica concretions, silicified tepees and silcretes. FA2 represents nearshore deposits and consists of fine-grained sandstones with evenly parallel lamination, climbing ripple cross-lamination, massive and megaripple bedding and mudstone/siltstone showing evenly parallel lamination. FA3 refers to wadi/inundite deposits, generally organized as fining-upward cycles of metric size, composed of conglomerates and medium-grained pebbly sandstones showing massive bedding and cross-stratification, as well as claystone/siltstone showing evenly parallel to undulate lamination. Scour-and-fill features are isolated in predominantly tabular deposits composed of mudstones interbedded with fine to medium-grained sandstones showing planar to slightly undulate lamination. Silicified plant remains previously classified as belonging to the Psaronius genus found in the uppermost levels of the Pedra de Fogo Formation, near the

  10. Evidence of lacustrine sedimentation in the Upper Permian Bijori Formation, Satpura Gondwana basin: Palaeogeographic and tectonic implications

    Indian Academy of Sciences (India)

    Tapan Chakraborty; Soumen Sarkar


    The Upper Permian Bijori Formation of the Satpura Gondwana basin comprising fine- to coarsegrained sandstone, carbonaceous shale/mudstone and thin coal bands was previously interpreted as the deposits of meandering rivers. The present study documents abundance of wave ripples, hummocky and swaley cross-stratification and combined flow bedforms in the Bijori Formation, suggesting that a significant part of the formation was deposited in a wave-agitated environment. Evidence of near-emergent depositional conditions provided by repeated occurrence of rootlet beds and hydromorphic paleosols, local flooding surfaces denoting rapid fluctuation of water level, occurrences of temnospondyl vertebrate fossils, and absence of tidal signatures and marine fossils suggest a lacustrine rather than marine depositional regime. Five facies associations recognised within the Bijori Formation are inferred to represent fluvial channels and associated floodplains (FA1), lake shorelines (FA2), subaqueous distributary channels and associated levees (FA3), wave- and storm-affected delta front (FA4), and open lacustrine/lower shoreface (FA5) deposits. The planoconcave fluvial channel-fill sandbodies with unidirectional cross-beds are clearly distinguishable from the delta front bars that show a convexo-plan or bi-convex sandbody geometry and dominance of wave and combined flow bedforms. Some of the distributary channels record interaction of fluvial and wave-dominated basinal processes. Major distributary sandbodies show a north to northwest flow direction while wave-affected delta front sandbodies show very complex flow patterns reflecting interaction between fluvial discharge and wave processes. Wave ripple crest trends show that the lake shoreline had an overall east–northeast to west–southwest orientation. The lack of documented contemporaneous lacustrine or marine sediments in the Satpura Gondwana basin posed a major problem of basin-scale palaeogeographic reconstruction. The

  11. Middle Permian paleomagnetism of the Sydney Basin, Eastern Gondwana: Testing Pangea models and the timing of the end of the Kiaman Reverse Superchron (United States)

    Belica, M. E.; Tohver, E.; Pisarevsky, S. A.; Jourdan, F.; Denyszyn, S.; George, A. D.


    Paleomagnetic and geochronologic data from the eastern margin of Gondwana have been obtained from the Gerringong Volcanics in the southern Sydney Basin, Australia. The corresponding paleomagnetic pole at 56.9°S, 154.8°E (N = 131; A95 = 9.1°) has a 40Ar/39Ar plagioclase plateau age of 265.05 ± 0.35 [0.46] Ma from the Bumbo Latite, and overlaps with recent radio-isotopic and paleomagnetic results published from Western Gondwana. The long-documented inconsistency between Middle Permian Eastern and Western Gondwanan paleomagnetic datasets is most likely an artefact of a lack of reliable paleomagnetic data from Eastern Gondwana for this period. A number of well-dated and recently published ca. 265 Ma paleomagnetic results from Gondwana and Laurussia are shown to be consistent with the Wegenerian Pangea A configuration, with a loose N-S fit of the continents for the Middle Permian. The lack of crustal overlap negates the need for a Pangea B configuration, which if valid must have been assembled to Pangea A by ca. 265 Ma. The reverse polarity Bumbo Latite was sampled from the Kiaman type-section located in the southern Sydney Basin. Three cases of normal polarity were detected in the overlying Saddleback, Dapto, and Berkeley Latites, previously assigned to the Kiaman Reverse Superchron (KRS). We review KRS-aged magnetostratigraphic data and propose that an age assignment of 265 Ma most likely represents the termination of the non-reversing field, with longer stable intervals of normal polarity recorded and able to be correlated globally.

  12. Linguistic Diversity in the Pacific. (United States)

    Crowley, Terry


    Reviews Peter Muhlhausler's book "Linguistic Ecology: Language Change and Linguistic Imperialism in the Pacific Region." Discusses the linguistic diversity of the Pacific, the linguistic impact of colonialism in the Pacific, and the role of linguists in the evolving linguistic situation in the Pacific. (Author/VWL)

  13. The Choiyoi volcanic province at 34°S-36°S (San Rafael, Mendoza, Argentina): Implications for the Late Palaeozoic evolution of the southwestern margin of Gondwana (United States)

    Kleiman, Laura E.; Japas, María S.


    The Choiyoi rhyolitic province of Chile and Argentina (23°S-42°S) was emplaced at the SW margin of Gondwana during the Permian. The San Rafael Massif (Mendoza, Argentina, 34°-36°S), is a key area to analyse the relative timing of Choyoi magmatism and related deformation as it bears one of the most complete and well exposed succession. Stratigraphic, structural and magmatic studies indicate that major changes of geodynamic conditions occurred during the Permian since arc-related sequences syntectonic with transpression (lower Choiyoi) were followed by transitional to intraplate, postorogenic suites coeval with transtension (upper Choiyoi). During the Early Permian, a major event of N-NNW dextral transpressional motions deformed the Carboniferous foreland basin in the San Rafael Massif. This event is attributed to the first episode of the San Rafael orogeny and can be related to oblique subduction (Az. 30°) of the Palaeo-Pacific plate. Ca. 280 Ma the inception of voluminous calc-alkaline volcanism (lower Choiyoi) syntectonic with WNW sinistral transpression of the second episode of the San Rafael orogeny, is associated with an eastward migration of the magmatic arc at this latitude. To the southeast of San Rafael, magmatism and transpression continued to migrate inland suggesting that a progressively younger, WNW, sinistral, thick skinned deformation belt broadens into the foreland and can be traced from San Rafael to Sierra de la Ventana, linking the San Rafael orogeny with the Gondwanide orogeny of the Cape Fold Belt in South Africa. This distribution of magmatism and deformation is interpreted as being the consequence of a progressive shallowing of the Palaeo-Pacific plate starting to the north of San Rafael, and culminating with a flat-slab region south of 36°S. Ca. 265 Ma the onset of predominantly felsic volcanism (upper Choiyoi) in San Rafael occurred in a Post-San Rafael extensional setting. Kinematic indicators and strain fabric analyses of San Rafael

  14. Ancestral genes can control the ability of horizontally acquired loci to confer new traits.

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    H Deborah Chen


    Full Text Available Horizontally acquired genes typically function as autonomous units conferring new abilities when introduced into different species. However, we reasoned that proteins preexisting in an organism might constrain the functionality of a horizontally acquired gene product if it operates on an ancestral pathway. Here, we determine how the horizontally acquired pmrD gene product activates the ancestral PmrA/PmrB two-component system in Salmonella enterica but not in the closely related bacterium Escherichia coli. The Salmonella PmrD protein binds to the phosphorylated PmrA protein (PmrA-P, protecting it from dephosphorylation by the PmrB protein. This results in transcription of PmrA-dependent genes, including those conferring polymyxin B resistance. We now report that the E. coli PmrD protein can activate the PmrA/PmrB system in Salmonella even though it cannot do it in E. coli, suggesting that these two species differ in an additional component controlling PmrA-P levels. We establish that the E. coli PmrB displays higher phosphatase activity towards PmrA-P than the Salmonella PmrB, and we identified a PmrB subdomain responsible for this property. Replacement of the E. coli pmrB gene with the Salmonella homolog was sufficient to render E. coli resistant to polymyxin B under PmrD-inducing conditions. Our findings provide a singular example whereby quantitative differences in the biochemical activities of orthologous ancestral proteins dictate the ability of a horizontally acquired gene product to confer species-specific traits. And they suggest that horizontally acquired genes can potentiate selection at ancestral loci.

  15. On the ancestral recruitment of metalloproteinases into the venom of snakes. (United States)

    Casewell, Nicholas R


    Tracing the evolutionary history of proteins can reveal insights into gene alterations responsible for changes in structure and function. Here, the origin of snake venom metalloproteinases was rigorously reassessed using phylogenetics and the reconstruction of ancestral sequences. Basal SVMPs are most closely related to ADAM 7, 28 and decysin-1 proteins. Reconstructing the evolutionary history of these proteins and their hypothetical ancestors reveals progressive alterations in the amino acid composition and structural characteristics of ADAMs/SVMPs through evolutionary time.

  16. The ancestral karyotype of Carnivora: comparison with that of platyrrhine monkeys. (United States)

    Dutrillaux, B; Couturier, J


    The karyotypes of six species of Carnivora (Mungos mungo, Paradoxurus hermaphroditus, Potos flavus, Mustela furo, Felis serval, and Halichoerus grypus), representative of five different families, were studied and compared. Correspondence between almost all chromosome segments was found, and a presumed ancestral karyotype of Carnivora is proposed. Analogies to human chromosomes are also given, and the results obtained are in excellent agreement with previously published gene mapping data on man and the domestic cat.

  17. Ancestral Protein Reconstruction Yields Insights into Adaptive Evolution of Binding Specificity in Solute-Binding Proteins. (United States)

    Clifton, Ben E; Jackson, Colin J


    The promiscuous functions of proteins are an important reservoir of functional novelty in protein evolution, but the molecular basis for binding promiscuity remains elusive. We used ancestral protein reconstruction to experimentally characterize evolutionary intermediates in the functional expansion of the polar amino acid-binding protein family, which has evolved to bind a variety of amino acids with high affinity and specificity. High-resolution crystal structures of an ancestral arginine-binding protein in complex with l-arginine and l-glutamine show that the promiscuous binding of l-glutamine is enabled by multi-scale conformational plasticity, water-mediated interactions, and selection of an alternative conformational substate productive for l-glutamine binding. Evolution of specialized glutamine-binding proteins from this ancestral protein was achieved by displacement of water molecules from the protein-ligand interface, reducing the entropic penalty associated with the promiscuous interaction. These results provide a structural and thermodynamic basis for the co-option of a promiscuous interaction in the evolution of binding specificity.

  18. Diverse adaptations of an ancestral gill: a common evolutionary origin for wings, breathing organs, and spinnerets. (United States)

    Damen, Wim G M; Saridaki, Theodora; Averof, Michalis


    Changing conditions of life impose new requirements on the morphology and physiology of an organism. One of these changes is the evolutionary transition from aquatic to terrestrial life, leading to adaptations in locomotion, breathing, reproduction, and mechanisms for food capture. We have shown previously that insects' wings most likely originated from one of the gills of ancestral aquatic arthropods during their transition to life on land. Here we investigate the fate of these ancestral gills during the evolution of another major arthropod group, the chelicerates. We examine the expression of two developmental genes, pdm/nubbin and apterous, that participate in the specification of insects' wings and are expressed in particular crustacean epipods/gills. In the horseshoe crab, a primitively aquatic chelicerate, pdm/nubbin is specifically expressed in opisthosomal appendages that give rise to respiratory organs called book gills. In spiders (terrestrial chelicerates), pdm/nubbin and apterous are expressed in successive segmental primordia that give rise to book lungs, lateral tubular tracheae, and spinnerets, novel structures that are used by spiders to breathe on land and to spin their webs. Combined with morphological and palaeontological evidence, these observations suggest that fundamentally different new organs (wings, air-breathing organs, and spinnerets) evolved from the same ancestral structure (gills) in parallel instances of terrestrialization.

  19. Ancestral informative marker selection and population structure visualization using sparse Laplacian eigenfunctions.

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    Jun Zhang

    Full Text Available Identification of a small panel of population structure informative markers can reduce genotyping cost and is useful in various applications, such as ancestry inference in association mapping, forensics and evolutionary theory in population genetics. Traditional methods to ascertain ancestral informative markers usually require the prior knowledge of individual ancestry and have difficulty for admixed populations. Recently Principal Components Analysis (PCA has been employed with success to select SNPs which are highly correlated with top significant principal components (PCs without use of individual ancestral information. The approach is also applicable to admixed populations. Here we propose a novel approach based on our recent result on summarizing population structure by graph laplacian eigenfunctions, which differs from PCA in that it is geometric and robust to outliers. Our approach also takes advantage of the priori sparseness of informative markers in the genome. Through simulation of a ring population and the real global population sample HGDP of 650K SNPs genotyped in 940 unrelated individuals, we validate the proposed algorithm at selecting most informative markers, a small fraction of which can recover the similar underlying population structure efficiently. Employing a standard Support Vector Machine (SVM to predict individuals' continental memberships on HGDP dataset of seven continents, we demonstrate that the selected SNPs by our method are more informative but less redundant than those selected by PCA. Our algorithm is a promising tool in genome-wide association studies and population genetics, facilitating the selection of structure informative markers, efficient detection of population substructure and ancestral inference.

  20. What was the ancestral sex-determining mechanism in amniote vertebrates? (United States)

    Johnson Pokorná, Martina; Kratochvíl, Lukáš


    Amniote vertebrates, the group consisting of mammals and reptiles including birds, possess various mechanisms of sex determination. Under environmental sex determination (ESD), the sex of individuals depends on the environmental conditions occurring during their development and therefore there are no sexual differences present in their genotypes. Alternatively, through the mode of genotypic sex determination (GSD), sex is determined by a sex-specific genotype, i.e. by the combination of sex chromosomes at various stages of differentiation at conception. As well as influencing sex determination, sex-specific parts of genomes may, and often do, develop specific reproductive or ecological roles in their bearers. Accordingly, an individual with a mismatch between phenotypic (gonadal) and genotypic sex, for example an individual sex-reversed by environmental effects, should have a lower fitness due to the lack of specialized, sex-specific parts of their genome. In this case, evolutionary transitions from GSD to ESD should be less likely than transitions in the opposite direction. This prediction contrasts with the view that GSD was the ancestral sex-determining mechanism for amniote vertebrates. Ancestral GSD would require several transitions from GSD to ESD associated with an independent dedifferentiation of sex chromosomes, at least in the ancestors of crocodiles, turtles, and lepidosaurs (tuataras and squamate reptiles). In this review, we argue that the alternative theory postulating ESD as ancestral in amniotes is more parsimonious and is largely concordant with the theoretical expectations and current knowledge of the phylogenetic distribution and homology of sex-determining mechanisms.

  1. Ancestral state reconstruction, rate heterogeneity, and the evolution of reptile viviparity. (United States)

    King, Benedict; Lee, Michael S Y


    Virtually all models for reconstructing ancestral states for discrete characters make the crucial assumption that the trait of interest evolves at a uniform rate across the entire tree. However, this assumption is unlikely to hold in many situations, particularly as ancestral state reconstructions are being performed on increasingly large phylogenies. Here, we show how failure to account for such variable evolutionary rates can cause highly anomalous (and likely incorrect) results, while three methods that accommodate rate variability yield the opposite, more plausible, and more robust reconstructions. The random local clock method, implemented in BEAST, estimates the position and magnitude of rate changes on the tree; split BiSSE estimates separate rate parameters for pre-specified clades; and the hidden rates model partitions each character state into a number of rate categories. Simulations show the inadequacy of traditional models when characters evolve with both asymmetry (different rates of change between states within a character) and heterotachy (different rates of character evolution across different clades). The importance of accounting for rate heterogeneity in ancestral state reconstruction is highlighted empirically with a new analysis of the evolution of viviparity in squamate reptiles, which reveal a predominance of forward (oviparous-viviparous) transitions and very few reversals.

  2. Ancestral sleep. (United States)

    de la Iglesia, Horacio O; Moreno, Claudia; Lowden, Arne; Louzada, Fernando; Marqueze, Elaine; Levandovski, Rosa; Pilz, Luisa K; Valeggia, Claudia; Fernandez-Duque, Eduardo; Golombek, Diego A; Czeisler, Charles A; Skene, Debra J; Duffy, Jeanne F; Roenneberg, Till


    While we do not yet understand all the functions of sleep, its critical role for normal physiology and behaviour is evident. Its amount and temporal pattern depend on species and condition. Humans sleep about a third of the day with the longest, consolidated episode during the night. The change in lifestyle from hunter-gatherers via agricultural communities to densely populated industrialized centres has certainly affected sleep, and a major concern in the medical community is the impact of insufficient sleep on health [1,2]. One of the causal mechanisms leading to insufficient sleep is altered exposure to the natural light-dark cycle. This includes the wide availability of electric light, attenuated exposure to daylight within buildings, and evening use of light-emitting devices, all of which decrease the strength of natural light-dark signals that entrain circadian systems [3].

  3. The late Paleozoic palynological diversity in southernmost Paraná (Uruguay), Claromecó and Paganzo basins (Argentina), Western Gondwana (United States)

    Beri, Ángeles; Gutiérrez, Pedro R.; Balarino, M. Lucía


    This study explores the changes in palynoflora diversity of the late Paleozoic in boreholes DI.NA.MI.GE. 254 (26 samples) and DI.NA.MI.GE. 221 (14 samples) of the Paraná Basin in Uruguay and in 18 surface samples of the La Deheza Formation (Paganzo Basin) and 10 samples of borehole UTAL.CMM1.La Estrella.x-1 (Claromecó Basin) in Argentina. Possible relationships among biostratigraphic zones, diversity levels, facies and climatic evolution patterns in Western Gondwana are studied. Diversity curves of boreholes 221 and 254 and the La Deheza Formation outcrop exhibit similar diversity evolution patterns, i.e., an increase in lower strata diversity and a decrease in upper strata diversity. The disappearance events are determined to be more prominent in biozones of the Cisuralian to the Guadalupian age and less prominent in biozones of the early Cisuralian age. The number of genera raises from the glaciomarine facies, through the deltaic and the marine facies, up to the shallow marine or lagoon facies, in which the disappearance rates become more prominent. . The diversity of the lower part of the La Estrella borehole is lesser than that of the other sequences These diversity, disappearance and appearance behaviors may reflect post-glacial climatic amelioration patterns and the beginning of an arid phase.

  4. Cooperation Over The Pacific

    Institute of Scientific and Technical Information of China (English)


    Recently,there has been a media blitz both in the United States and beyond about the nation's "return to the Pacific" and the advent of an "American Pacific Century."Though the United States has never left the region-it has had a presence in the Asia-Pacific for more than 200 years-the notion of a U.S "return" to the region is prevalent.It was U.S.Secretary of State Hillary Clinton who told the world that "the United States is back in Southeast Asia." Over the coming decade,she said,one of the priorities of American statecraft will be "to lock in a substantially increased investment-diplomatic,economic,strategic,and otherwise-in the Asia-Pacific region."

  5. Paleomagnetic study of Siluro-Devonian volcanic rocks from the central Lachlan Orogen: Implications for the apparent pole wander path of Gondwana (United States)

    VéRard, Christian; Tait, Jennifer; Glen, Richard


    The apparent pole wander (APW) path for Gondwana is still not clearly established, in particular, for Silurian-Devonian times. A controversial debate places authors who argue for an "X path," running directly through Africa on a reconstruction of Gondwana against those who advocate a large loop passing by southern South America, the "Y path." Most of the paleomagnetic data used to draw this loop come from the Lachlan Orogen (Australia). A paleomagnetic study was carried out in the well-dated Ambone and Ural volcanics in the central subprovince of Lachlan Orogen, New South Wales. Anisotropy of magnetic susceptibility measurements confirms detailed mapping of the region and shows that these massive dacitic sills and/or lava flows are flat lying. Among the different localities studied, only one yields interpretable paleomagnetic results. Two components of magnetization can be identified: a midtemperature direction yielding a corresponding pole in Australian coordinates λ = 67.9°S/ϕ = 084.4°E (B = 5; n = 21; dp = 17.5°/dm = 23.1°) and a high-temperature direction with a corresponding VGP λ = 24.4°S/ϕ = 060.6°E (B = 5; n = 25; dp = 1.4°/dm = 2.5°). The first is interpreted as corresponding to an Early Carboniferous pole position and can be regarded as an overprint probably related to the Early Carboniferous Kanimblan orogenic event. The second does not correspond to any expected Silurian-Devonian or younger pole position. This magnetization is thought to be primary in origin; however, secular variation has apparently not been averaged out in the single lava flow sampled. Therefore the earliest Devonian paleopole position probably lies in a 30° cone around the obtained VGP, and this position can only match the X-type APW path for Gondwana. It is in particular very different from coeval poles obtained in the eastern subprovince of the Lachlan Orogen, and it is mostly used as key poles supporting the Silurian-Devonian loop for the APW path of Gondwana

  6. Evidence that the ancestral haplotype in Australian hemochromatosis patients may be associated with a common mutation in the gene

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, D.H.G.; Powell, L.W.; Leggett, B.A. [Univ. of Queensland (Australia)] [and others


    Hemochromatosis (HC) is a common inherited disorder of iron metabolism for which neither the gene nor biochemical defect have yet been identified. The aim of this study was to look for clinical evidence that the predominant ancestral haplotype in Australian patients is associated with a common mutation in the gene. We compared indices of iron metabolism and storage in three groups of HC patients categorized according to the presence of the ancestral haplotype (i.e., patients with two copies, one copy, and no copies of the ancestral haplotype). We also examined iron indices in two groups of HC heterozygotes (those with the ancestral haplotype and those without) and in age-matched controls. These analyses indicate that (i) HC patients with two copies of the ancestral haplotype show significantly more severe expression of the disorder than those with one copy or those without, (ii) HC heterozygotes have partial clinical expression, which may be influenced by the presence of the ancestral haplotype in females but not in males, and (iii) the high population frequency of the HC gene may be the result of the selective advantage conferred by protecting heterozygotes against iron deficiency. 18 refs., 3 tabs.

  7. Stroke and Native Hawaiians/Pacific Islanders (United States)

    ... Population Profiles > Native Hawaiian/Other Pacific Islander > Stroke Stroke and Native Hawaiians/Pacific Islanders Native Hawaiians/Pacific ... non-Hispanic white adults to die from a stroke in 2010. In general, Native Hawaiian/Pacific Islander ...

  8. Travelling in time with networks: Revealing present day hybridization versus ancestral polymorphism between two species of brown algae, Fucus vesiculosus and F. spiralis

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    Pearson Gareth A


    Full Text Available Abstract Background Hybridization or divergence between sympatric sister species provides a natural laboratory to study speciation processes. The shared polymorphism in sister species may either be ancestral or derive from hybridization, and the accuracy of analytic methods used thus far to derive convincing evidence for the occurrence of present day hybridization is largely debated. Results Here we propose the application of network analysis to test for the occurrence of present day hybridization between the two species of brown algae Fucus spiralis and F. vesiculosus. Individual-centered networks were analyzed on the basis of microsatellite genotypes from North Africa to the Pacific American coast, through the North Atlantic. Two genetic distances integrating different time steps were used, the Rozenfeld (RD; based on alleles divergence and the Shared Allele (SAD; based on alleles identity distances. A diagnostic level of genotype divergence and clustering of individuals from each species was obtained through RD while screening for exchanges through putative hybridization was facilitated using SAD. Intermediate individuals linking both clusters on the RD network were those sampled at the limits of the sympatric zone in Northwest Iberia. Conclusion These results suggesting rare hybridization were confirmed by simulation of hybrids and F2 with directed backcrosses. Comparison with the Bayesian method STRUCTURE confirmed the usefulness of both approaches and emphasized the reliability of network analysis to unravel and study hybridization

  9. Kinematic constraints on buckling a lithospheric-scale orocline along the northern margin of Gondwana: A geologic synthesis (United States)

    Weil, A. Brandon; Gutiérrez-Alonso, G.; Johnston, S. T.; Pastor-Galán, D.


    The Paleozoic Variscan orogeny was a large-scale collisional event involving amalgamation of multiple continents and micro-continents. Existing data, suggests oroclinal buckling of an originally near-linear convergent margin during the last stages of Variscan deformation in the late Paleozoic. Closure of the Rheic Ocean resulted in E-W shortening (present-day coordinates) in the Carboniferous, producing a near linear N-S trending, east-verging belt. Subsequent N-S shortening near the Carb-Permian boundary resulted in oroclinal buckling. This late-stage orogenic event remains an enigmatic part of final Pangea amalgamation. The present-day arc curvature of the Variscan has inspired many tectonic models, with little agreement between them. While there is general consensus that two separate phases of deformation occurred, various models consider that curvature was caused by: dextral transpression around a Gondwana indentor; strike-slip wrench tectonics; or a change in tectonic transport direction due to changing stress fields. More recent models explain the curvature as an orocline, with potentially two opposite-facing bends, caused by secondary rotations. Deciphering the kinematic history of curved orogens is difficult, and requires establishment of two deformation phases: an initial compressive phase that forms a relatively linear belt, and a second phase that causes vertical-axis rotation of the orogenic limbs. Historically the most robust technique to accurately quantify vertical axis-rotation in curved orogens is paleomagnetic analysis, but recently other types of data, including fracture, geochemical, petrologic, paleo-current and calcite twin data, have been used to corroborate secondary buckling. A review of existing and new Variscan data from Iberia is presented that argues for secondary buckling of an originally linear orogenic system. Together, these data constrain oroclinal buckling of the Cantabrian Orocline to have occurred in about 10 Ma during the

  10. Geology of the Grove Mountains in East Antarctica--New evidence for the final suture of Gondwana Land

    Institute of Scientific and Technical Information of China (English)

    LIU; Xiaohan(刘小汉); ZHAO; Yue(赵越); LIU; Xiaochun(刘晓春); YU; Liangjun(俞良军)


    Grove Mountains consists mainly of a series of high-grade (upper amphibolite to granulite facies) metamorphic rocks, including felsic granulite, granitic gneiss, mafic granulite lenses and charnockite, intruded by late tectonic gneissic granite and post-tectonic granodioritic veins. Geochemical analysis demonstrates that the charnockite, granitic gneiss and granite belonged to aluminous A type plutonic rocks, whereas the felsic and mafic granulite were from supracrustal materials as island-arc, oceanic island and middle oceanic ridge basalt. A few high-strained shear zones disperse in regional stable sub-horizontal foliated metamorphic rocks. Three generations of ductile deformation were identified, in which D1 is related to the event before Pan-African age, D2 corresponds to the regional granulite peak metamorphism, whereas D3 reflects ductile extension in late Pan-African orogenic period. The metamorphic reactions from granitic gneiss indicate a single granulite facies event, but 3 steps from mafic granulite, with P-T condition of M1 800℃, 9.3×105 Pa; M2 800-810℃, 6.4×105 Pa ; and M3 650℃ have been recognized. The U-Pb age data from representative granitic gneiss indicate (529±14) Ma of peak metamorphism, (534±5) Ma of granite emplacement, and (501±7) Ma of post-tectonic granodioritic veins. All these evidences suggest that a huge Pan-African aged mobile belt exists in the East Antarctic Shield extending from Prydz Bay via Grove Mountains to the southern Prince Charles Mountains. This orogenic belt could be the final suture during the Gondwana Land assemblage.

  11. Neanderthal and Denisova genetic affinities with contemporary humans: introgression versus common ancestral polymorphisms. (United States)

    Lowery, Robert K; Uribe, Gabriel; Jimenez, Eric B; Weiss, Mark A; Herrera, Kristian J; Regueiro, Maria; Herrera, Rene J


    Analyses of the genetic relationships among modern humans, Neanderthals and Denisovans have suggested that 1-4% of the non-Sub-Saharan African gene pool may be Neanderthal derived, while 6-8% of the Melanesian gene pool may be the product of admixture between the Denisovans and the direct ancestors of Melanesians. In the present study, we analyzed single nucleotide polymorphism (SNP) diversity among a worldwide collection of contemporary human populations with respect to the genetic constitution of these two archaic hominins and Pan troglodytes (chimpanzee). We partitioned SNPs into subsets, including those that are derived in both archaic lineages, those that are ancestral in both archaic lineages and those that are only derived in one archaic lineage. By doing this, we have conducted separate examinations of subsets of mutations with higher probabilities of divergent phylogenetic origins. While previous investigations have excluded SNPs from common ancestors in principal component analyses, we included common ancestral SNPs in our analyses to visualize the relative placement of the Neanderthal and Denisova among human populations. To assess the genetic similarities among the various hominin lineages, we performed genetic structure analyses to provide a comparison of genetic patterns found within contemporary human genomes that may have archaic or common ancestral roots. Our results indicate that 3.6% of the Neanderthal genome is shared with roughly 65.4% of the average European gene pool, which clinally diminishes with distance from Europe. Our results suggest that Neanderthal genetic associations with contemporary non-Sub-Saharan African populations, as well as the genetic affinities observed between Denisovans and Melanesians most likely result from the retention of ancient mutations in these populations.

  12. Chromosome painting in three-toed sloths: a cytogenetic signature and ancestral karyotype for Xenarthra

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    Azevedo Nathália F


    Full Text Available Abstract Background Xenarthra (sloths, armadillos and anteaters represent one of four currently recognized Eutherian mammal supraorders. Some phylogenomic studies point to the possibility of Xenarthra being at the base of the Eutherian tree, together or not with the supraorder Afrotheria. We performed painting with human autosomes and X-chromosome specific probes on metaphases of two three-toed sloths: Bradypus torquatus and B. variegatus. These species represent the fourth of the five extant Xenarthra families to be studied with this approach. Results Eleven human chromosomes were conserved as one block in both B. torquatus and B. variegatus: (HSA 5, 6, 9, 11, 13, 14, 15, 17, 18, 20, 21 and the X chromosome. B. torquatus, three additional human chromosomes were conserved intact (HSA 1, 3 and 4. The remaining human chromosomes were represented by two or three segments on each sloth. Seven associations between human chromosomes were detected in the karyotypes of both B. torquatus and B. variegatus: HSA 3/21, 4/8, 7/10, 7/16, 12/22, 14/15 and 17/19. The ancestral Eutherian association 16/19 was not detected in the Bradypus species. Conclusions Our results together with previous reports enabled us to propose a hypothetical ancestral Xenarthran karyotype with 48 chromosomes that would differ from the proposed ancestral Eutherian karyotype by the presence of the association HSA 7/10 and by the split of HSA 8 into three blocks, instead of the two found in the Eutherian ancestor. These same chromosome features point to the monophyly of Xenarthra, making this the second supraorder of placental mammals to have a chromosome signature supporting its monophyly.

  13. Characterizing genetic diversity of contemporary pacific chickens using mitochondrial DNA analyses.

    Directory of Open Access Journals (Sweden)

    Kelsey Needham Dancause

    Full Text Available BACKGROUND: Mitochondrial DNA (mtDNA hypervariable region (HVR sequences of prehistoric Polynesian chicken samples reflect dispersal of two haplogroups--D and E--by the settlers of the Pacific. The distribution of these chicken haplogroups has been used as an indicator of human movement. Recent analyses suggested similarities between prehistoric Pacific and South American chicken samples, perhaps reflecting prehistoric Polynesian introduction of the chicken into South America. These analyses have been heavily debated. The current distribution of the D and E lineages among contemporary chicken populations in the Western Pacific is unclear, but might ultimately help to inform debates about the movements of humans that carried them. OBJECTIVES: We sought to characterize contemporary mtDNA diversity among chickens in two of the earliest settled archipelagos of Remote Oceania, the Marianas and Vanuatu. METHODS: We generated HVR sequences for 43 chickens from four islands in Vanuatu, and for 5 chickens from Guam in the Marianas. RESULTS: Forty samples from Vanuatu and three from Guam were assigned to haplogroup D, supporting this as a Pacific chicken haplogroup that persists in the Western Pacific. Two haplogroup E lineages were observed in Guam and two in Vanuatu. Of the E lineages in Vanuatu, one was identical to prehistoric Vanuatu and Polynesian samples and the other differed by one polymorphism. Contrary to our expectations, we observed few globally distributed domesticate lineages not associated with Pacific chicken dispersal. This might suggest less European introgression of chickens into Vanuatu than expected. If so, the E lineages might represent lineages maintained from ancient Pacific chicken introductions. The Vanuatu sample might thus provide an opportunity to distinguish between maintained ancestral Pacific chicken lineages and replacement by global domesticates through genomic analyses, which could resolve questions of contemporary

  14. Eastern Pacific Ocean Conference (United States)

    The promotion of interaction among investigators of all oceanographic disciplines studying the eastern Pacific Ocean was the goal of the 1990 Eastern Pacific Ocean Conference (EPOC), held October 17-19 on the snow-covered slopes of Mt. Hood, Oreg. Thirty oceanographers representing all disciplines attended.Dick Barber, Duke University Marine Lab, Beaufort, N.C., chaired a session on the eastern equatorial Pacific Ocean, emphasizing issues related to biological activity. Steve Ramp of the Naval Postgraduate School in Montery, Calif., chaired a session on recent results from northern and central California experiments. On October 19, following an early morning earthquake, a business meeting and discussions regarding a collaboration in future experiments were held.

  15. Sustainability of ancestral methods of agricultural production in Perú: ¿keep or replace?

    Directory of Open Access Journals (Sweden)

    Dani Eduardo Vargas Huanca


    Full Text Available Based on the success of some Andean products such as quinoa, potatoes or maca in international food trade and the growing environmental degradation facing developing countries, resulting from intensive exploitation activities; Our research seeks to show the trend that is assumed from the academic / scientific community and public officials in the food sector in Peru, against the need to maintain sustainable various ancestral modes of agricultural production (case quinoa, for it analyze quantitative and qualitative obtained from public institutions and Peruvian universities.

  16. Sandals as Icons: Representations in Ancestral Pueblo Rock Art and Effigies in Stone and Wood


    Polly Schaafsma


    Dating the late 1000s to the mid-1200s CE, petroglyphs of sandal images are among others that distinguish ancient Pueblo rock art in the San Juan and Little Colorado River drainages on the Colorado Plateau from Ancestral Pueblo rock art elsewhere across the Southwest. The sandal “track” also has counterparts  as effigies in stone and wood often found in ceremonial contexts in Pueblo sites. These representations reflect the sandal styles of the times, both plain in contour and the jog-toed var...

  17. Rugose corals at the Tournaisian-Viséan transition in the Central Taurides (S Turkey) - Palaeobiogeography and palaeoceanography of the Asian Gondwana margin (United States)

    Denayer, Julien


    This paper gives the first taxonomic description of the Upper Tournaisian-Lower Viséan rugose coral fauna of the Yaricak Formation (Aladag Unit, Central Taurides, South Turkey). Fifteen species belonging to twelve genera were identified, one species is newly described: Eokoninckocarinia gemmina. The corals are stratigraphically distributed in four assemblages. The two typical assemblages of the Upper Tournaisian are composed of widely distributed taxa (Uralinia, Caninia, Proheterelasma, Zaphrentites). The assemblage crossing the Tournaisian-Viséan boundary is characterized by Eurasian and cosmopolitan and widely distributed taxa (Calmiussiphyllum, Siphonophyllia, Bifossularia Amygdalophyllum, Caninophyllum, Keyserlingophyllum) and Asian taxa (Kueichouphyllum). The youngest assemblage, dominated by Eokoninckocarinia gemmina sp. nov., has yielded foraminifers Moliniacian (Lower Viséan) in age. These assemblages form a low diversity level-bottom community which is typical of the South Palaeotethys 'Kueichouphyllum Zone' extending along the Asian margin of Gondwana (Cimmerian Terrane) during Lower Carboniferous times. As in the other Cimmerian blocks, all the corals are solitary and colonial taxa are virtually absent. This absence is tentatively explained by the high palaeolatitude (c. 50°S) position of the Cimmerian Terrane in the southern part of the Palaeotethys Ocean for this time slice. A cold-water palaeo-current running eastward along the Gondwana margin might also be considered as it possibly could explain the wide distribution of the Kueichouphyllum fauna, restricted east of Africa in the southern coast of the Palaeotethys. Palaeoceanography, palaeoclimate and facies issues are discussed as possible causes of the diversity gradient observed between the eastern (Australia, Malaya) and the western (North Africa) margin of the Gondwana.

  18. Tectonic insight based on anisotropy of magnetic susceptibility and compaction studies in the Sierras Australes thrust and fold belt (southwest Gondwana boundary, Argentina) (United States)

    Arzadún, Guadalupe; Tomezzoli, Renata N.; Cesaretti, Nora N.


    The Sierras Australes fold and thrust belt (Buenos Aires Province, Argentina) was in the southwestern Gondwanaland margin during the Paleozoic. The Tunas Formation (Permian) is exposed along the eastern part of it and continues eastward beneath the Claromecó Basin. Anisotropy of magnetic susceptibility (AMS) and compaction studies are described and compared with previous paleomagnetic studies with the aim of determining direction and magnitude of the main stresses acting during the sedimentation of the Tunas Formation. The anisotropy ellipsoids are triaxial with oblate or prolate shapes, reflecting different stages of layer parallel shortening during the evolution of the basin. Kmax axes trend NW-SE, parallel to the fold axes, while Kmin move from a horizontal (base) to a vertical orientation at the top of the succession, showing a change from a tectonic to almost a sedimentary fabric. The magnitude of anisotropy and compaction degree decreases toward the top of the succession. The AMS results are consistent with the outcrop structural observations and the compaction and paleomagnetic data. Regional pattern indicates a compression from the SW along this part of Gondwana, with a migration of the orogenic front and attenuation toward the NE in the foreland basin during the Upper Paleozoic. This deformation, locally assigned to the San Rafael noncollisional orogenic phase, is the result of the latitudinal movements toward the Equator of Gondwana (southern plates) and Laurentia (northern plates) during the Permian. This movement is the result of a rearrangement of the microplates that collided with Gondwana during the Late Devonian, to configure Pangea during the Triassic.

  19. Did Patagonia collide against Gondwana in the Late Paleozoic? Some Insights From Magnetic Fabrics of Granitoids in the North Patagonian Massif. (United States)

    Rapalini, A. E.; Lopez de Luchi, M. G.; Tomezzoli, R. N.


    The Paleozoic tectonic evolution of Patagonia has been a matter of much debate in the last two decades. There is no consensus on whether the North Patagonian Massif (NPM) was accreted by a frontal collision to Gondwana in the Late Paleozoic or if it shared a similar paleotectonic evolution with other Gondwana blocks during the Paleozoic. Different geologic, geochronologic, geophysical and structural data have been interpreted either as supporting or refuting the collisional model. Paleomagnetic data obtained so far is consistent with an authochtonous evolution since the Devonian, but it does not rule out relative displacements of up to 1500 km between Patagonia and Gondwana.Therefore, a Late Paleozoic frontal collision cannot be definitely ruled out on the basis of paleomagnetic data alone. As part of a muldisciplinary research project a magnetic fabric study, by means of the anisotropy of magnetic susceptibility (AMS), was carried out on Late Paleozoic granitoids exposed in northeastern NPM. Two main composite units were studied, the highly to variably foliated Yaminue Complex, poorly dated as Late Carboniferous and ranging in composition from tonalite to leuco-granite, and the much less deformed granodiorites to monzoganites of the Early Permian (283 Ma) Navarrete complex. While the former is composed of both ferro and paramagnetic units, with a dominance of the latter; the Navarrete plutons are basically ferromagnetic. Directional and scalar AMS results joined with meso and microstructural studies permitted the characterization of the deformational and magmatic fabric of the different units. An evolutionary picture of the succesive intrusive events in NPM emerged which confirms an important NNE-SSW contractional event associated with intrusion of the different units that compose the Yaminue Complex. This event ended before the intrusion of the Navarrete Complex, which is governed by a different stress regime. Our results fit the hypothesis of a collisional event

  20. Palaeotsunamis in the Pacific Islands (United States)

    Goff, J.; Chague-Goff, C.; Dominey-Howes, D.; McAdoo, B.; Cronin, S.; Bonte-Grapetin, Michael; Nichol, S.; Horrocks, M.; Cisternas, M.; Lamarche, G.; Pelletier, B.; Jaffe, B.; Dudley, W.


    The recent 29 September 2009 South Pacific and 27 February 2010 Chilean events are a graphic reminder that the tsunami hazard and risk for the Pacific Ocean region should not be forgotten. Pacific Islands Countries (PICs) generally have short (Elsevier B.V.

  1. Consistency and inconsistency of consensus methods for inferring species trees from gene trees in the presence of ancestral population structure. (United States)

    DeGiorgio, Michael; Rosenberg, Noah A


    In the last few years, several statistically consistent consensus methods for species tree inference have been devised that are robust to the gene tree discordance caused by incomplete lineage sorting in unstructured ancestral populations. One source of gene tree discordance that has only recently been identified as a potential obstacle for phylogenetic inference is ancestral population structure. In this article, we describe a general model of ancestral population structure, and by relying on a single carefully constructed example scenario, we show that the consensus methods Democratic Vote, STEAC, STAR, R(∗) Consensus, Rooted Triple Consensus, Minimize Deep Coalescences, and Majority-Rule Consensus are statistically inconsistent under the model. We find that among the consensus methods evaluated, the only method that is statistically consistent in the presence of ancestral population structure is GLASS/Maximum Tree. We use simulations to evaluate the behavior of the various consensus methods in a model with ancestral population structure, showing that as the number of gene trees increases, estimates on the basis of GLASS/Maximum Tree approach the true species tree topology irrespective of the level of population structure, whereas estimates based on the remaining methods only approach the true species tree topology if the level of structure is low. However, through simulations using species trees both with and without ancestral population structure, we show that GLASS/Maximum Tree performs unusually poorly on gene trees inferred from alignments with little information. This practical limitation of GLASS/Maximum Tree together with the inconsistency of other methods prompts the need for both further testing of additional existing methods and development of novel methods under conditions that incorporate ancestral population structure.

  2. Magnetic fabric and microstructures of Late Paleozoic granitoids from the North Patagonian Massif: Evidence of a collision between Patagonia and Gondwana? (United States)

    López de Luchi, Mónica G.; Rapalini, Augusto E.; Tomezzoli, Renata N.


    Widespread Late Paleozoic magmatism in northern Patagonia is a target to test hypotheses on the long standing question over the origin of Patagonia. In recent years, a dispute over whether it is an accreted crustal block that collided with Gondwana in Paleozoic times or an autochthonous part of South America has taken place. As part of a multidisciplinary study, an integrated microstructural and magnetic fabric study was carried out on the Late Carboniferous Yaminué Complex and the Early Permian Navarrete Plutonic Complex, both exposed in the northeastern corner of the North Patagonian Massif (40.5°S, 67.0°W). Other investigated units are the Late Carboniferous Tardugno Granodiorite, the newly defined Cabeza de Vaca Granite and the Late Permian San Martin pluton. Over 300 oriented cores from 60 sites were collected for anisotropy of magnetic susceptibility (AMS) measurements. A systematic analysis of around 100 petrographic thin sections was performed to characterize the microstructures of the different magmatic units. Microstructures in the Yaminué Complex are indicative of a transition from magmatic to solid-state deformation. Microstructures of the orthogneiss of tonalitic composition suggest an early stage in the emplacement history of this complex. The Cabeza de Vaca Granite, intrusive in Yaminué Complex, is the most evolved unit and records less intense high-temperature solid-state deformation which suggests that the stress field that controlled the emplacement of the Yaminué Complex outlasted it. According to petrologic and structural considerations, the Navarrete Plutonic Complex has been subdivided into three facies, i.e. Robaina, Guanacos and Aranda, respectively. Microstructures of the Navarrete Plutonic Complex are mostly magmatic to submagmatic, versus the solid-state fabric that characterizes the Robaina facies at the contact with the Yaminué Complex. Combined analyses of AMS and microstructural data lead us to suggest that the Yaminué Complex

  3. New geochemical and geochronological data of early Cambrian of (SW Iberia): Calc-alkaline magmatism in the transition from active to passive continental margin in North Gondwana


    Sanchez-Garcia, Teresa; Pereira, M. Francisco; Bellido, Felix; Chichorro, Martim; Silva, J. Brandao; Valverde-Vaquero, Pablo; Pin, Christian; Solá, Rita


    The Ossa-Morena Zone (SW Iberia) displays a well-preserved record of the history of the northern Gondwana margin in Late Ediacaran-Early Cambrian times. This period of time is marked by the late-stage evolution of the Cadomian magmatic arc and related back-arc basins (c. 590-545 Ma), and the onset of rifting and widespread magmatism (c. 530-500 Ma) that led to the opening of the Rheic Ocean. Here we present new geochemical and geochronological data on some Cambrian granitoids of Ossa-Morena ...

  4. Bearing the unbearable: ancestral transmission through dreams and moving metaphors in the analtyic field. (United States)

    Pickering, Judith


    This paper explores how untold and unresolved intergenerational trauma may be transmitted through unconscious channels of communication, manifesting in the dreams of descendants. Unwitting carriers for that which was too horrific for their ancestors to bear, descendants may enter analysis through an unconscious need to uncover past secrets, piece together ancestral histories before the keys to comprehending their terrible inheritance die with their forebears. They seek the relational containment of the analytic relationship to provide psychological conditions to bear the unbearable, know the unknowable, speak the unspeakable and redeem the unredeemable. In the case of 'Rachael', initial dreams gave rise to what Hobson (1984) called 'moving metaphors of self' in the analytic field. Dream imagery, projective and introjective processes in the transference-countertransference dynamics gradually revealed an unknown ancestral history. I clarify the back and forth process from dream to waking dream thoughts to moving metaphors and differentiate the moving metaphor from a living symbol. I argue that the containment of the analytic relationship nested within the security of the analytic space is a necessary precondition for such healing processes to occur.

  5. Ancestral origin of the ATTCT repeat expansion in spinocerebellar ataxia type 10 (SCA10.

    Directory of Open Access Journals (Sweden)

    Teresa Almeida

    Full Text Available Spinocerebellar ataxia type 10 (SCA10 is an autosomal dominant neurodegenerative disease characterized by cerebellar ataxia and seizures. The disease is caused by a large ATTCT repeat expansion in the ATXN10 gene. The first families reported with SCA10 were of Mexican origin, but the disease was soon after described in Brazilian families of mixed Portuguese and Amerindian ancestry. The origin of the SCA10 expansion and a possible founder effect that would account for its geographical distribution have been the source of speculation over the last years. To unravel the mutational origin and spread of the SCA10 expansion, we performed an extensive haplotype study, using closely linked STR markers and intragenic SNPs, in families from Brazil and Mexico. Our results showed (1 a shared disease haplotype for all Brazilian and one of the Mexican families, and (2 closely-related haplotypes for the additional SCA10 Mexican families; (3 little or null genetic distance in small normal alleles of different repeat sizes, from the same SNP lineage, indicating that they are being originated by a single step mechanism; and (4 a shared haplotype for pure and interrupted expanded alleles, pointing to a gene conversion model for its generation. In conclusion, we show evidence for an ancestral common origin for SCA10 in Latin America, which might have arisen in an ancestral Amerindian population and later have been spread into the mixed populations of Mexico and Brazil.

  6. The mosaic of ancestral karyotype blocks in the Sinapis alba L. genome. (United States)

    Nelson, Matthew N; Parkin, Isobel A P; Lydiate, Derek J


    The organisation of the Sinapis alba genome, comprising 12 linkage groups (n = 12), was compared with the Brassicaceae ancestral karyotype (AK) genomic blocks previously described in other crucifer species. Most of the S. alba genome falls into conserved triplicated genomic blocks that closely match the AK-defined genomic blocks found in other crucifer species including the A, B, and C genomes of closely related Brassica species. In one instance, an S. alba linkage group (S05) was completely collinear with one AK chromosome (AK1), the first time this has been observed in a member of the Brassiceae tribe. However, as observed for other members of the Brassiceae tribe, ancestral genomic blocks were fragmented in the S. alba genome, supporting previously reported comparative chromosome painting describing rearrangements of the AK karyotype prior to the divergence of the Brassiceae from other crucifers. The presented data also refute previous phylogenetic reports that suggest S. alba was more closely related to Brassica nigra (B genome) than to B. rapa (A genome) and B. oleracea (C genome). A comparison of the S. alba and Arabidopsis thaliana genomes revealed many regions of conserved gene order, which will facilitate access to the rich genomic resources available in the model species A. thaliana for genetic research in the less well-resourced crop species S. alba.

  7. On the historical biogeography of global Galliformes: ancestral range and diversification patterns

    Institute of Scientific and Technical Information of China (English)

    Youhua; Chen


    Background: In this study, the ancestral distributional ranges and the tempo of diversification patterns of global Galliformes were investigated.Methods: Different diversification models characterizing possible tempo patterns were fitted and compared onto the phylogenetic tree for the 197 Galliforme species, consisting of a constant-speciation and constant-extinction model(CONSTANT), a decreasing-speciation and constant-extinction model(SPVAR), a constant-speciation and increasing-extinction model(EXVAR) and a decreasing-speciation and increasing-extinction model(BOTHVAR).Ancestral range reconstruction was conducted using the dispersal-extinction-cladogenesis model.Results: A constant-diversification-rate(CONSTANT) model best quantified the historical speciation patterns of this avian assemblage through model selection. Clade age and species richness are significantly and positively correlated. The most recent common ancestor for Galliformes species was originally found in the disjunctive regions between Southeast Asia and North America. High-frequency dispersal events were identified across the whole evolutionary time.Conclusions: The constant diversification rate for global Galliforme species implied that there were no diversification rate-shifting trends for Galliformes species. The present study may contribute to the understanding of the ecology and diversity patterns of Galliformes from the perspective of historical biogeography, although some limitations existed.

  8. Ancestral Protein Reconstruction and Circular Permutation for Improving the Stability and Dynamic Range of FRET Sensors. (United States)

    Clifton, Ben E; Whitfield, Jason H; Sanchez-Romero, Inmaculada; Herde, Michel K; Henneberger, Christian; Janovjak, Harald; Jackson, Colin J


    Small molecule biosensors based on Förster resonance energy transfer (FRET) enable small molecule signaling to be monitored with high spatial and temporal resolution in complex cellular environments. FRET sensors can be constructed by fusing a pair of fluorescent proteins to a suitable recognition domain, such as a member of the solute-binding protein (SBP) superfamily. However, naturally occurring SBPs may be unsuitable for incorporation into FRET sensors due to their low thermostability, which may preclude imaging under physiological conditions, or because the positions of their N- and C-termini may be suboptimal for fusion of fluorescent proteins, which may limit the dynamic range of the resulting sensors. Here, we show how these problems can be overcome using ancestral protein reconstruction and circular permutation. Ancestral protein reconstruction, used as a protein engineering strategy, leverages phylogenetic information to improve the thermostability of proteins, while circular permutation enables the termini of an SBP to be repositioned to maximize the dynamic range of the resulting FRET sensor. We also provide a protocol for cloning the engineered SBPs into FRET sensor constructs using Golden Gate assembly and discuss considerations for in situ characterization of the FRET sensors.

  9. Internal structural variations in a debris-avalanche deposit from ancestral Mount Shasta, California, USA (United States)

    Ui, T.; Glicken, H.


    Various parameters of the internal structure of a debris-avalanche deposit from ancestral Mount Shasta (size and percentage of block facies in each exposure, number and width of jigsaw cracks, and number of rounded clasts in matrix facies) were measured in order to study flow and emplacement mechanisms. Three types of coherent blocks were identified: blocks of massive or brecciated lava flows or domes, blocks of layered volcaniclastic deposits, and blocks of accidental material, typically from sedimentary units underlying Shasta Valley. The mean maximum dimension of the three largest blocks of layered volcaniclastic material is 220 m, and that of the lava blocks, 110 m. This difference may reflect plastic deformation of blocks of layered volcaniclastic material; blocks of massive or brecciated volcanic rock deformated brittly and may have split into several smaller blocks. The blocks in the deposit are one order of magnitude larger, and the height of collapse 1100 m higher, than the Pungarehu debris-avalanche deposit at Mount Egmont, New Zealand, although the degree of fracturing is about the same.This suggests either that the Shasta source material was less broken, or that the intensity of any accompanying explosion was smaller at ancestral Mount Shasta. The Shasta debris-avalanche deposit covered the floor of a closed basin; the flanks of the basin may have retarded the opening of jigsaw cracks and the formation of stretched and deformed blocks such as those of the Pungarehu debris-avalanche deposit. ?? 1986 Springer-Verlag.

  10. Evolution of steroid receptors from an estrogen-sensitive ancestral receptor. (United States)

    Eick, Geeta N; Thornton, Joseph W


    Members of the steroid hormone receptor (SR) family activate transcription from different DNA response elements and are regulated by distinct hormonal ligands. Understanding the evolutionary process by which this diversity arose can provide insight into how and why SRs function as they do. Here we review the characteristics of the ancient receptor protein from which the SR family descends by a process of gene duplication and divergence. Several orthogonal lines of evidence - bioinformatic, phylogenetic, and experimental - indicate that this ancient SR had the capacity to activate transcription from DNA estrogen response elements in response to estrogens. Duplication and divergence of the ancestral SR gene subsequently generated new receptors that were activated by other steroid hormones, including progestagens, androgens, and corticosteroids. The androgen and progesterone receptors recruited as their ligands steroids that were previously present as biochemical intermediates in the synthesis of estrogens. This process is an example of molecular exploitation--the evolution of new molecular interactions when an older molecule, which previously had a different function, is co-opted as a binding partner by a newly evolved molecule. The primordial interaction between the ancestral steroid receptor and estrogens may itself have evolved due to an early molecular exploitation event.

  11. QTL linkage analysis of connected populations using ancestral marker and pedigree information. (United States)

    Bink, Marco C A M; Totir, L Radu; ter Braak, Cajo J F; Winkler, Christopher R; Boer, Martin P; Smith, Oscar S


    The common assumption in quantitative trait locus (QTL) linkage mapping studies that parents of multiple connected populations are unrelated is unrealistic for many plant breeding programs. We remove this assumption and propose a Bayesian approach that clusters the alleles of the parents of the current mapping populations from locus-specific identity by descent (IBD) matrices that capture ancestral marker and pedigree information. Moreover, we demonstrate how the parental IBD data can be incorporated into a QTL linkage analysis framework by using two approaches: a Threshold IBD model (TIBD) and a Latent Ancestral Allele Model (LAAM). The TIBD and LAAM models are empirically tested via numerical simulation based on the structure of a commercial maize breeding program. The simulations included a pilot dataset with closely linked QTL on a single linkage group and 100 replicated datasets with five linkage groups harboring four unlinked QTL. The simulation results show that including parental IBD data (similarly for TIBD and LAAM) significantly improves the power and particularly accuracy of QTL mapping, e.g., position, effect size and individuals' genotype probability without significantly increasing computational demand.

  12. Ancestral state reconstruction infers phytopathogenic origins of sooty blotch and flyspeck fungi on apple. (United States)

    Ismail, Siti Izera; Batzer, Jean Carlson; Harrington, Thomas C; Crous, Pedro W; Lavrov, Dennis V; Li, Huanyu; Gleason, Mark L


    Members of the sooty blotch and flyspeck (SBFS) complex are epiphytic fungi in the Ascomycota that cause economically damaging blemishes of apples worldwide. SBFS fungi are polyphyletic, but approx. 96% of SBFS species are in the Capnodiales. Evolutionary origins of SBFS fungi remain unclear, so we attempted to infer their origins by means of ancestral state reconstruction on a phylogenetic tree built utilizing genes for the nuc 28S rDNA (approx. 830 bp from near the 59 end) and the second largest subunit of RNA polymerase II (RPB2). The analyzed taxa included the well-known genera of SBFS as well as non-SBFS fungi from seven families within the Capnodiales. The non-SBFS taxa were selected based on their distinct ecological niches, including plant-parasitic and saprophytic species. The phylogenetic analyses revealed that most SBFS species in the Capnodiales are closely related to plant-parasitic fungi. Ancestral state reconstruction provided strong evidence that plant-parasitic fungi were the ancestors of the major SBFS lineages. Knowledge gained from this study may help to better understand the ecology and evolution of epiphytic fungi.

  13. Reconstructing an ancestral mammalian immune supercomplex from a marsupial major histocompatibility complex.

    Directory of Open Access Journals (Sweden)

    Katherine Belov


    Full Text Available The first sequenced marsupial genome promises to reveal unparalleled insights into mammalian evolution. We have used the Monodelphis domestica (gray short-tailed opossum sequence to construct the first map of a marsupial major histocompatibility complex (MHC. The MHC is the most gene-dense region of the mammalian genome and is critical to immunity and reproductive success. The marsupial MHC bridges the phylogenetic gap between the complex MHC of eutherian mammals and the minimal essential MHC of birds. Here we show that the opossum MHC is gene dense and complex, as in humans, but shares more organizational features with non-mammals. The Class I genes have amplified within the Class II region, resulting in a unique Class I/II region. We present a model of the organization of the MHC in ancestral mammals and its elaboration during mammalian evolution. The opossum genome, together with other extant genomes, reveals the existence of an ancestral "immune supercomplex" that contained genes of both types of natural killer receptors together with antigen processing genes and MHC genes.

  14. Cambrian cinctan echinoderms shed light on feeding in the ancestral deuterostome. (United States)

    Rahman, Imran A; Zamora, Samuel; Falkingham, Peter L; Phillips, Jeremy C


    Reconstructing the feeding mode of the latest common ancestor of deuterostomes is key to elucidating the early evolution of feeding in chordates and allied phyla; however, it is debated whether the ancestral deuterostome was a tentaculate feeder or a pharyngeal filter feeder. To address this, we evaluated the hydrodynamics of feeding in a group of fossil stem-group echinoderms (cinctans) using computational fluid dynamics. We simulated water flow past three-dimensional digital models of a Cambrian fossil cinctan in a range of possible life positions, adopting both passive tentacular feeding and active pharyngeal filter feeding. The results demonstrate that an orientation with the mouth facing downstream of the current was optimal for drag and lift reduction. Moreover, they show that there was almost no flow to the mouth and associated marginal groove under simulations of passive feeding, whereas considerable flow towards the animal was observed for active feeding, which would have enhanced the transport of suspended particles to the mouth. This strongly suggests that cinctans were active pharyngeal filter feeders, like modern enteropneust hemichordates and urochordates, indicating that the ancestral deuterostome employed a similar feeding strategy.

  15. A FORTRAN subroutine to compute inbreeding and kinship coefficients according to the number of ancestral generations. (United States)

    Vu Tien Khang, J


    This paper presents a FORTRAN IV subroutine to calculate inbreeding and kinship coefficients from pedigree information in a diploid population without self-fertilization. The user can specify the number of ancestral generations to be taken into account. It is thus possible to determine contributions of succeeding ancestral generations to the inbreeding and kinship coefficients under consideration. The subroutine is based on a recursive procedure that generates systematically all paths connecting two individuals. NP and NM, whose kinship coefficient is to be calculated (or between the father NP and the mother NM of the individual whose inbreeding coefficient is to be calculated). These paths obey the following conditions: (i) a given path does not contain the same parent-offspring link more than once; (ii) the vertex of a path is an ancestor common to individuals NP and NM, with a rank lower or equal to the parameter specified in input. Constraints regarding the size of the corpus of genealogical data and the storage method are discussed, as well as the interest of this subroutine compared to the existing ones. An example of application is given.

  16. On the Potential Origins of the High Stability of Reconstructed Ancestral Proteins. (United States)

    Trudeau, Devin L; Kaltenbach, Miriam; Tawfik, Dan S


    Ancestral reconstruction provides instrumental insights regarding the biochemical and biophysical characteristics of past proteins. A striking observation relates to the remarkably high thermostability of reconstructed ancestors. The latter has been linked to high environmental temperatures in the Precambrian era, the era relating to most reconstructed proteins. We found that inferred ancestors of the serum paraoxonase (PON) enzyme family, including the mammalian ancestor, exhibit dramatically increased thermostabilities compared with the extant, human enzyme (up to 30 °C higher melting temperature). However, the environmental temperature at the time of emergence of mammals is presumed to be similar to the present one. Additionally, the mammalian PON ancestor has superior folding properties (kinetic stability)-unlike the extant mammalian PONs, it expresses in E. coli in a soluble and functional form, and at a high yield. We discuss two potential origins of this unexpectedly high stability. First, ancestral stability may be overestimated by a "consensus effect," whereby replacing amino acids that are rare in contemporary sequences with the amino acid most common in the family increases protein stability. Comparison to other reconstructed ancestors indicates that the consensus effect may bias some but not all reconstructions. Second, we note that high stability may relate to factors other than high environmental temperature such as oxidative stress or high radiation levels. Foremost, intrinsic factors such as high rates of genetic mutations and/or of transcriptional and translational errors, and less efficient protein quality control systems, may underlie the high kinetic and thermodynamic stability of past proteins.

  17. On the historical biogeography of global Galliformes:ancestral range and diversification patterns

    Institute of Scientific and Technical Information of China (English)

    Youhua Chen


    Background:In this study, the ancestral distributional ranges and the tempo of diversification patterns of global Galliformes were investigated. Methods:Different diversification models characterizing possible tempo patterns were fitted and compared onto the phylogenetic tree for the 197 Galliforme species, consisting of a constant-speciation and constant-extinction model (CONSTANT), a decreasing-speciation and constant-extinction model (SPVAR), a constant-speciation and increasing-extinction model (EXVAR) and a decreasing-speciation and increasing-extinction model (BOTHVAR). Ancestral range reconstruction was conducted using the dispersal-extinction-cladogenesis model. Results:A constant-diversification-rate (CONSTANT) model best quantified the historical speciation patterns of this avian assemblage through model selection. Clade age and species richness are significantly and positively correlated. The most recent common ancestor for Galliformes species was originally found in the disjunctive regions between Southeast Asia and North America. High-frequency dispersal events were identified across the whole evolutionary time. Conclusions:The constant diversification rate for global Gal iforme species implied that there were no diversification rate-shifting trends for Galliformes species. The present study may contribute to the understanding of the ecology and diversity patterns of Galliformes from the perspective of historical biogeography, although some limitations existed.

  18. The East Pacific Rise

    NARCIS (Netherlands)



    Evidence gathered by expeditions of the University of California’s Scripps Institution of Oceanography during the International Geophysical Year suggests that the East Pacific Rise is one of the largest physical structures on earth. It runs in a sickle-shaped curve from near New Zealand 8,000 miles

  19. Pacific Island Pharmacovigilance

    DEFF Research Database (Denmark)

    McEwen, John; Vestergaard, Lasse S.; Sanburg, Amanda L C


    Many Pacific Island countries (PICs) are recipients of funding support from the Global Fund to Fight AIDS, Tuberculosis and Malaria (Global Fund). However, most of these countries cannot be expected to meet Global Fund and World Health Organization (WHO) minimum requirements for a functioning...

  20. OCLC in Asia Pacific. (United States)

    Chang, Min-min


    Discusses the Online Computer Library Center (OCLC) and the changing Asia Pacific library scene under the broad headings of the three phases of technology innovation. Highlights include WorldCat and the OCLC shared cataloging system; resource sharing and interlibrary loan; enriching OCLC online catalog with Asian collections; and future outlooks.…

  1. Australia in the Pacific. (United States)

    Kennedy, Kerry; Welch, Ian


    Discusses Australia's growth since European settlement and its development into a major world trader in industrial and high technology raw materials. Examines the country's expanding relations with New Zealand and other Pacific states which is the outgrowth of the realization that all will gain from greater international cooperation. (GEA)

  2. Modelos de cinemática de placas para Antártida durante la ruptura de Gondwana: una revisión Plate kinematic models for Antactica during Gondwana break-up: A review

    Directory of Open Access Journals (Sweden)

    M.E. Ghidella


    Full Text Available La historia de apertura del mar de Weddell y del Oc éano Atlántico Sur es crítica para comprender la ruptura de Gondwana y la evolución geológica de Antártida desde el Jurásico temprano. La dispersión de los fragmentos gondwánicos es importante para entender la circulación oceánica del pasado, descifrar la historia de las cuencas sedimentarias ubicadas al Este de la Península Antártica y establecer posibles rutas de dispersión de flora y fauna entre los continentes australes. Desafortunadamente, la tectónica del mar de Weddell es difícil de resolver debido a la escasez de datos y a su inherente complejidad. Aunque se ha alcanzado un progreso muy grande el los últimos 20 años, con nuevos datos aeromagnéticos marinos y mapas de gravedad derivada de altimetría satelital, todavía hay varios modelos en consideración que difieren en edades corticales y esquemas de apertura. En este trabajo se presenta una revisión de cuatro de esos modelos. Utilizando polos de rotación, isócronas sintéticas y líneas de flujo, se ha procedido hacia atrás en el tiempo comenzando en la anomalía magnética 34 (83,5 millones de años, porque la misma está relativamente bien definida en los océanos, y se presentan mapas de edades de corteza que muestran la trayectoria estimada del punto triple Sudamérica - Antártida - África para cada modelo. Asimismo se muestran gráficos de las reconstrucciones en cuatro épocas elegidas para todos los modelos usando la misma proyección y escala para facilitar la comparación. La variedad de suposiciones simplificadoras que debieron hacerse en cada modelo, recurriendo a fragmentación de placas para considerar las numerosas cuencas de syn-rift y períodos de extensión, son fuertes indicadores de que la tectónica de placas rígidas es un modelo demasiado simple para el presente problema.The opening history of both the Weddell Sea and South Atlantic Ocean is critical to understand the break-up of

  3. The Fairway-Aotea Basin and the New Caledonia Trough, witnesses of the Pacific-Australian plate boundary evolution : from mid-Cretaceous cessation of subduction to Eocene subduction renewal (United States)

    Collot, J.; Geli, L. B.; Lafoy, Y.; Sutherland, R.; Herzer, R. H.; Roest, W. R.


    The geodynamical history of the SW Pacific is controlled since the Mesozoic by the evolution of peri-Pacific subduction zones, in a trench retreat by slab roll-back process, which successively occurred along the Eastern Gondwana margin. In this context, most basins which formed after 45 Ma reached a stage of seafloor spreading, have recorded the inversions of the earth's magnetic field and present typical oceanic crust morphologies. By contrast, the New Caledonia and Fairway basins, which are narrower and present thick sedimentary covers have a less known and more controversial origin. Based on a regional geological synthesis and on interpretation of multichannel seismic reflection and refraction data, combined with drill hole data off New Zealand and a compilation of regional potential data, we distinguish 2 phases of the evolution of the Fairway-Aotea Basin (FAB) and the New Caledonia Trough (NCT), which reflect the evolution of the Gondwana-Pacific plate boundary: Phase 1: Mid Cretaceous formation of the FAB in a continental intra- or back- arc position of the Pacific-Gondwana subduction system. The formation of this shallow basin reflects the onset of continental breakup of the Eastern Gondwana margin during Cenomanian which was most probably caused by a dynamic change of the subduction zone through a « verticalization » of the slab. This event may be the result of the 99 Ma kinematic plate reorganization which probably led to subduction cessation along the Gondwana-Pacific plate boundary. A tectonic escape mechanism, in relation with the locking of the subduction zone by the Hikurangi Plateau, could also be responsible of the trench retreat leading to backarc extension. Phase 2: Regional Eocene-Oligocene uplift followed by rapid subsidence (3-4 km) of the system « Lord Howe Rise - FAB - Norfolk Ridge ». The structural style of this deformation leads us to suggest that detachment of the lower crust is the cause of subsidence. We therefore propose a model in

  4. Control of deep lithospheric roots on crustal scale GOCE gravity and gradient fields evident in Gondwana reconstructions (United States)

    Braitenberg, Carla; Mariani, Patrizia


    implications from complete Gondwana GOCE-products reconstructions and link to lithospheric roots. Proceedings of 5th International GOCE User Workshop, 25 - 28 November 2014. Braitenberg, C. (2015). Exploration of tectonic structures with GOCE in Africa and across-continents. Int. J.Appl. Earth Observ. Geoinf. 35, 88-95. Braitenberg, C. (2015). A grip on geological units with GOCE, IAG Symp. 141, in press.

  5. Early Callovian ingression in southwestern Gondwana. Palaeoenvironmental evolution of the carbonate ramp (Calabozo Formation) in southwestern Mendoza, Neuquen basin, Argentina (United States)

    Armella, Claudia; Cabaleri, Nora G.; Cagnoni, Mariana C.; Panarello, Héctor O.


    The carbonatic sequence of the Calabozo Formation (Lower Callovian) developed in southwestern Gondwana, within the northern area of the Neuquén basin, and is widespread in thin isolated outcrops in southwestern Mendoza province, Argentina. This paper describes the facies, microfacies and geochemical-isotopic analysis carried out in five studied localities, which allowed to define the paleoenvironmental conditions of a homoclinal shallow ramp model, highly influenced by sea level fluctuations, where outer, mid and inner ramp subenvironments were identified. The outer ramp subenvironment was only recognized in the south of the depocenter and is characterized by proximal outer ramp facies with shale levels and interbedded mudstone and packstone layers. The mid ramp subenvironment is formed by low energy facies (wackestone) affected by storms (packstones, grainstones and floatstones). The inner ramp subenvironment is the most predominant and is characterized by tidal flat facies (wackestones, packstones and grainstones) over which a complex of shoals (grainstones and packstones) dissected by tidal channels (packstone, grainstones and floatstones) developed. In the north area, protected environment facies were recorded (bioturbated wackestones and packstones). The vertical distribution of facies indicates that the paleoenvironmental evolution of the Calabozo Formation results from a highstand stage in the depocenter, culminating in a supratidal environment, with stromatolitic levels interbedded with anhydrite originated under restricted water circulation conditions due to a progressive isolation of the basin. δ13C and δ18O values of the carbonates of the Calabozo Formation suggest an isotopic signature influenced by local palaeoenvironmental parameters and diagenetic overprints. The δ13C and δ18O oscillations between the carbonates of the different studied sections are related with lateral facies variations within the carbonate ramp accompanied with dissimilar

  6. Post-Gondwana geomorphic evolution of southwestern Africa: Implications for hte controls on landscape development from observations and numerical experiments (United States)

    Gilchrist, Alan R.; Kooi, Henk; Beaumont, Christopher


    The relationship between morphology and surficial geology is used to quantify the denudation that has occurred across southwestern Africa sicne the fragmentation of Gondwana during the Early Mesozoic. Two main points emerge. Signficant denudation, of the order of kilometers, is widespread except in the Kalahari region of the continental interior. The denudation is systematically distributed so that the continental exterior catchment, draining directly to the Cape basin, is denuded to a greater depth than the interior catchment inland of the Great Escarpment. The analysis also implies tha the majority of the denudation occurred before the beginning of the Cenozoic for both teh exerior and interior catchments. Existing models of landscape development are reviewed, and implications of the denudation chronology are incorporated into a revised conceptual model. This revision implies tha thte primary effect of rifting on the subsequent landscape evolution is that it generates two distinct drainage regimes. A marginal upwarp, or rift flank uplift, separates rejuvenated rivers that drain into the subsiding rift from rivers in the continetal interior that are deflected but not rejuvenated. The two catchments evolve independently unless they are integrated by breaching of hte marginal upwarp. If this occurs, the exterior baselevel is communicated to the interior catchment that is denuded accordingly. Denudation rates generally decrease as the margin evolves, and this decrease is reinforced by the exposure of substrate that is resistant to denudation and/or a change to a more arid climate. The observations do not reveal a particular style of smaller-scale landscape evolution, sucha s escarpment retreat, that is responsible for the differential denudation across the region. It is proposed that numerical model experiments, which reflect the observational insights at the large scale, may identify the smaller-scale controls on escarpment development if the model and natural

  7. Eolian deposits of the southwestern margin of the Botucatú paleoerg: Reconstruction of the Gondwana landscape in Central Northern Argentina (United States)

    Peri, V. Gisel; Naipauer, Maximiliano; Pimentel, Marcio; Barcelona, Hernan


    The Mesozoic Botucatú paleoerg at the southwestern margin of Gondwana includes a succession of eolian dunes cross-strata which are presently exposed in Otumpa Hills (Central Northern Argentina). Here, the architectural facies, petrology, and provenance of those rocks were studied in order to investigate depositional environments and paleoclimates. The stratigraphic sequence included basal eolian two-dimensional crescentic dunes (Slp) overlain by three-dimensional crescentic dunes of smaller scale (Smt). These were correlated with the Upper Member Rivera of the Tacuarembó Formation (Uruguay), or its equivalent in Brazil, the Botucatú Formation. These outcrops partially mark the southwestern margin of the Botucatú paleoerg along the Chaco-Paraná Basin boundary. The paleocurrents from the W, NW, and SW and the U-Pb ages of detrital zircons indicate a main Pampean cratonic and secondary Andean magmatic arc (180 Ma) source. A detrital zircon of 180 Ma by U-Pb limits a maximum depositional age at 180 Ma (Toarcian) for facies Slp. Upwards, the phreatic silcrete and calcrete indicate semiarid conditions during the Paleocene, which are correlated with the Queguay Formation of Uruguay. A saprolite paleoweathering profile, recording wet tropical-hyper-tropical climate at the Early Eocene and representing the Gondwana landscape and climate conditions, crowns the sequence. This study represents the first provenance and surface texture analysis of minerals from the Botucatú paleoerg and was instrumental to unravel past environmental and sedimentary conditions.

  8. An overview of the Mesozoic-Cenozoic magmatism and tectonics in Eastern Paraguay and central Andes (Western Gondwana): Implications for the composition of mantle sources (United States)

    Omarini, Ricardo H.; Gasparon, Massimo; De Min, Angelo; Comin-Chiaramonti, Piero


    The amalgamation of the Western Gondwana (including the Greater Gondwana supercraton) occurred at 600 Ma during the Brazilian - Pan African orogeny. A plate junction related to this event is marked by the Transbrazilian lineament which separates the South American continent into two sectors: the Eastern Paraguay-Brazilian and Central Andean domains. An overview of the geodynamic data from these two sectors indicates that the two domains were subjected to distinct evolutions from the Proterozoic to the present. The Andean domain is characterized by long-lived subduction processes linked to the convergence and consequent collision of microplates since the Middle Proterozoic (western Amazonian Craton) with a peak at about 600-580 Ma. The Paraguay-Brazilian domain remained relatively stable but was affected by extension episodes that reactivated ancient (Early and Middle Proterozoic) suture zones. These different geodynamic evolutions seem to reflect broadly distinct mantle compositions. In the subduction zones of the Andean domain the mantle was deeply modified by metasomatic processes following the subduction of oceanic plates. Consequently, the Andean type magma sources show a clear HIMU imprint inherited from the MORB, whereas the Paraguay-Brazilian sector shows a prevalent EMI and subordinate EMII character. The petrological data mainly from Mesozoic and Cenozoic magmatic events in the two sectors are reviewed to investigate the current mantle plume and mantle dome models for the uprising of the asthenospheric (or sub-lithospheric) material.

  9. Toward more accurate ancestral protein genotype-phenotype reconstructions with the use of species tree-aware gene trees. (United States)

    Groussin, Mathieu; Hobbs, Joanne K; Szöllősi, Gergely J; Gribaldo, Simonetta; Arcus, Vickery L; Gouy, Manolo


    The resurrection of ancestral proteins provides direct insight into how natural selection has shaped proteins found in nature. By tracing substitutions along a gene phylogeny, ancestral proteins can be reconstructed in silico and subsequently synthesized in vitro. This elegant strategy reveals the complex mechanisms responsible for the evolution of protein functions and structures. However, to date, all protein resurrection studies have used simplistic approaches for ancestral sequence reconstruction (ASR), including the assumption that a single sequence alignment alone is sufficient to accurately reconstruct the history of the gene family. The impact of such shortcuts on conclusions about ancestral functions has not been investigated. Here, we show with simulations that utilizing information on species history using a model that accounts for the duplication, horizontal transfer, and loss (DTL) of genes statistically increases ASR accuracy. This underscores the importance of the tree topology in the inference of putative ancestors. We validate our in silico predictions using in vitro resurrection of the LeuB enzyme for the ancestor of the Firmicutes, a major and ancient bacterial phylum. With this particular protein, our experimental results demonstrate that information on the species phylogeny results in a biochemically more realistic and kinetically more stable ancestral protein. Additional resurrection experiments with different proteins are necessary to statistically quantify the impact of using species tree-aware gene trees on ancestral protein phenotypes. Nonetheless, our results suggest the need for incorporating both sequence and DTL information in future studies of protein resurrections to accurately define the genotype-phenotype space in which proteins diversify.

  10. Classifying Pacific islands (United States)

    Nunn, Patrick D.; Kumar, Lalit; Eliot, Ian; McLean, Roger F.


    An earth-science-based classification of islands within the Pacific Basin resulted from the preparation of a database describing the location, area, and type of 1779 islands, where island type is determined as a function of the prevailing lithology and maximum elevation of each island, with an island defined as a discrete landmass composed of a contiguous land area ≥1 ha (0.01 km2) above mean high-water level. Reefs lacking islands and short-lived (ocean setting as well as the biological attributes of Pacific islands. It may also be used in spatial assessments of second-order phenomena associated with the islands, such as their vulnerability to various disasters, coastal erosion, or ocean pollution as well as human populations, built infrastructure and natural resources.

  11. Where did the chili get its spice? Biogeography of capsaicinoid production in ancestral wild chili species. (United States)

    Tewksbury, Joshua J; Manchego, Carlos; Haak, David C; Levey, Douglas J


    The biogeography of pungency in three species of wild chili in the chaco and surrounding highland habitats of southeastern Bolivia is described. We report that Capsicum chacoense, C. baccatum, and C. eximium are polymorphic for production of capsaicin and its analogs, such that completely pungent and completely nonpungent individuals co-occur in some populations. In C. chacoense, the density of plants and the proportion of pungent plants increased with elevation. Above 900 m, all individuals in all populations except two were pungent; nonpungent individuals in at least one of the two polymorphic populations were likely a result of spreading by humans. The occurrence of pungent and nonpungent individuals in three species of ancestral Capsicum and the geographic variation of pungency within species suggest that production of capsaicin and its analogs entails both costs and benefits, which shift from one locality to another. Determining the selection pressures behind such shifts is necessary to understand the evolution of pungency in chilies.

  12. A phenol-enriched cuticle is ancestral to lignin evolution in land plants (United States)

    Renault, Hugues; Alber, Annette; Horst, Nelly A.; Basilio Lopes, Alexandra; Fich, Eric A.; Kriegshauser, Lucie; Wiedemann, Gertrud; Ullmann, Pascaline; Herrgott, Laurence; Erhardt, Mathieu; Pineau, Emmanuelle; Ehlting, Jürgen; Schmitt, Martine; Rose, Jocelyn K. C.; Reski, Ralf; Werck-Reichhart, Danièle


    Lignin, one of the most abundant biopolymers on Earth, derives from the plant phenolic metabolism. It appeared upon terrestrialization and is thought critical for plant colonization of land. Early diverging land plants do not form lignin, but already have elements of its biosynthetic machinery. Here we delete in a moss the P450 oxygenase that defines the entry point in angiosperm lignin metabolism, and find that its pre-lignin pathway is essential for development. This pathway does not involve biochemical regulation via shikimate coupling, but instead is coupled with ascorbate catabolism, and controls the synthesis of the moss cuticle, which prevents desiccation and organ fusion. These cuticles share common features with lignin, cutin and suberin, and may represent the extant representative of a common ancestor. Our results demonstrate a critical role for the ancestral phenolic metabolism in moss erect growth and cuticle permeability, consistent with importance in plant adaptation to terrestrial conditions. PMID:28270693

  13. Novel ancestral Dysferlin splicing mutation which migrated from the Iberian peninsula to South America. (United States)

    Vernengo, Luis; Oliveira, Jorge; Krahn, Martin; Vieira, Emilia; Santos, Rosário; Carrasco, Luisa; Negrão, Luís; Panuncio, Ana; Leturcq, France; Labelle, Veronique; Bronze-da-Rocha, Elsa; Mesa, Rosario; Pizzarossa, Carlos; Lévy, Nicolas; Rodriguez, Maria-Mirta


    Primary dysferlinopathies are a group of recessive heterogeneous muscular dystrophies. The most common clinical presentations are Miyoshi myopathy and LGMD2B. Additional presentations range from isolated hyperCKemia to severe functional disability. Symptomatology begins in the posterior muscle compartment of the calf and its clinical course progresses slowly in Miyoshi myopathy whereas LGMD2B involves predominantly the proximal muscles of the lower limbs. The age of onset ranges from 13 to 60years in Caucasians. We present five patients that carry a novel mutation in the exon12/intron12 boundary: c.1180_1180+7delAGTGCGTG (r.1054_1284del). We provide evidence of a founder effect due to a common ancestral origin of this mutation, detected in heterozygosity in four patients and in homozygosity in one patient.

  14. On the ancestral compatibility of two phylogenetic trees with nested taxa. (United States)

    Llabrés, Mercè; Rocha, Jairo; Rosselló, Francesc; Valiente, Gabriel


    Compatibility of phylogenetic trees is the most important concept underlying widely-used methods for assessing the agreement of different phylogenetic trees with overlapping taxa and combining them into common supertrees to reveal the tree of life. The notion of ancestral compatibility of phylogenetic trees with nested taxa was recently introduced. In this paper we analyze in detail the meaning of this compatibility from the points of view of the local structure of the trees, of the existence of embeddings into a common supertree, and of the joint properties of their cluster representations. Our analysis leads to a very simple polynomial-time algorithm for testing this compatibility, which we have implemented and is freely available for download from the BioPerl collection of Perl modules for computational biology.

  15. Genes Suggest Ancestral Colour Polymorphisms Are Shared across Morphologically Cryptic Species in Arctic Bumblebees.

    Directory of Open Access Journals (Sweden)

    Paul H Williams

    Full Text Available Our grasp of biodiversity is fine-tuned through the process of revisionary taxonomy. If species do exist in nature and can be discovered with available techniques, then we expect these revisions to converge on broadly shared interpretations of species. But for the primarily arctic bumblebees of the subgenus Alpinobombus of the genus Bombus, revisions by some of the most experienced specialists are unusual for bumblebees in that they have all reached different conclusions on the number of species present. Recent revisions based on skeletal morphology have concluded that there are from four to six species, while variation in colour pattern of the hair raised questions as to whether at least seven species might be present. Even more species are supported if we accept the recent move away from viewing species as morphotypes to viewing them instead as evolutionarily independent lineages (EILs using data from genes. EILs are recognised here in practice from the gene coalescents that provide direct evidence for their evolutionary independence. We show from fitting both general mixed Yule/coalescent (GMYC models and Poisson-tree-process (PTP models to data for the mitochondrial COI gene that there is support for nine species in the subgenus Alpinobombus. Examination of the more slowly evolving nuclear PEPCK gene shows further support for a previously unrecognised taxon as a new species in northwestern North America. The three pairs of the most morphologically similar sister species are separated allopatrically and prevented from interbreeding by oceans. We also find that most of the species show multiple shared colour patterns, giving the appearance of mimicry among parts of the different species. However, reconstructing ancestral colour-pattern states shows that speciation is likely to have cut across widespread ancestral polymorphisms, without or largely without convergence. In the particular case of Alpinobombus, morphological, colour-pattern, and

  16. Inferring genome-wide patterns of admixture in Qataris using fifty-five ancestral populations

    Directory of Open Access Journals (Sweden)

    Omberg Larsson


    Full Text Available Abstract Background Populations of the Arabian Peninsula have a complex genetic structure that reflects waves of migrations including the earliest human migrations from Africa and eastern Asia, migrations along ancient civilization trading routes and colonization history of recent centuries. Results Here, we present a study of genome-wide admixture in this region, using 156 genotyped individuals from Qatar, a country located at the crossroads of these migration patterns. Since haplotypes of these individuals could have originated from many different populations across the world, we have developed a machine learning method "SupportMix" to infer loci-specific genomic ancestry when simultaneously analyzing many possible ancestral populations. Simulations show that SupportMix is not only more accurate than other popular admixture discovery tools but is the first admixture inference method that can efficiently scale for simultaneous analysis of 50-100 putative ancestral populations while being independent of prior demographic information. Conclusions By simultaneously using the 55 world populations from the Human Genome Diversity Panel, SupportMix was able to extract the fine-scale ancestry of the Qatar population, providing many new observations concerning the ancestry of the region. For example, as well as recapitulating the three major sub-populations in Qatar, composed of mainly Arabic, Persian, and African ancestry, SupportMix additionally identifies the specific ancestry of the Persian group to populations sampled in Greater Persia rather than from China and the ancestry of the African group to sub-Saharan origin and not Southern African Bantu origin as previously thought.

  17. Ancestral state reconstruction by comparative analysis of a GRN kernel operating in echinoderms. (United States)

    Erkenbrack, Eric M; Ako-Asare, Kayla; Miller, Emily; Tekelenburg, Saira; Thompson, Jeffrey R; Romano, Laura


    Diverse sampling of organisms across the five major classes in the phylum Echinodermata is beginning to reveal much about the structure and function of gene regulatory networks (GRNs) in development and evolution. Sea urchins are the most studied clade within this phylum, and recent work suggests there has been dramatic rewiring at the top of the skeletogenic GRN along the lineage leading to extant members of the euechinoid sea urchins. Such rewiring likely accounts for some of the observed developmental differences between the two major subclasses of sea urchins-cidaroids and euechinoids. To address effects of topmost rewiring on downstream GRN events, we cloned four downstream regulatory genes within the skeletogenic GRN and surveyed their spatiotemporal expression patterns in the cidaroid Eucidaris tribuloides. We performed phylogenetic analyses with homologs from other non-vertebrate deuterostomes and characterized their spatiotemporal expression by quantitative polymerase chain reaction (qPCR) and whole-mount in situ hybridization (WMISH). Our data suggest the erg-hex-tgif subcircuit, a putative GRN kernel, exhibits a mesoderm-specific expression pattern early in Eucidaris development that is directly downstream of the initial mesodermal GRN circuitry. Comparative analysis of the expression of this subcircuit in four echinoderm taxa allowed robust ancestral state reconstruction, supporting hypotheses that its ancestral function was to stabilize the mesodermal regulatory state and that it has been co-opted and deployed as a unit in mesodermal subdomains in distantly diverged echinoderms. Importantly, our study supports the notion that GRN kernels exhibit structural and functional modularity, locking down and stabilizing clade-specific, embryonic regulatory states.

  18. Evolutionary history of assassin bugs (insecta: hemiptera: Reduviidae: insights from divergence dating and ancestral state reconstruction.

    Directory of Open Access Journals (Sweden)

    Wei Song Hwang

    Full Text Available Assassin bugs are one of the most successful clades of predatory animals based on their species numbers (∼6,800 spp. and wide distribution in terrestrial ecosystems. Various novel prey capture strategies and remarkable prey specializations contribute to their appeal as a model to study evolutionary pathways involved in predation. Here, we reconstruct the most comprehensive reduviid phylogeny (178 taxa, 18 subfamilies to date based on molecular data (5 markers. This phylogeny tests current hypotheses on reduviid relationships emphasizing the polyphyletic Reduviinae and the blood-feeding, disease-vectoring Triatominae, and allows us, for the first time in assassin bugs, to reconstruct ancestral states of prey associations and microhabitats. Using a fossil-calibrated molecular tree, we estimated divergence times for key events in the evolutionary history of Reduviidae. Our results indicate that the polyphyletic Reduviinae fall into 11-14 separate clades. Triatominae are paraphyletic with respect to the reduviine genus Opisthacidius in the maximum likelihood analyses; this result is in contrast to prior hypotheses that found Triatominae to be monophyletic or polyphyletic and may be due to the more comprehensive taxon and character sampling in this study. The evolution of blood-feeding may thus have occurred once or twice independently among predatory assassin bugs. All prey specialists evolved from generalist ancestors, with multiple evolutionary origins of termite and ant specializations. A bark-associated life style on tree trunks is ancestral for most of the lineages of Higher Reduviidae; living on foliage has evolved at least six times independently. Reduviidae originated in the Middle Jurassic (178 Ma, but significant lineage diversification only began in the Late Cretaceous (97 Ma. The integration of molecular phylogenetics with fossil and life history data as presented in this paper provides insights into the evolutionary history of

  19. Magmatism and Epithermal Gold-Silver Deposits of the Southern Ancestral Cascade Arc, Western Nevada and Eastern California (United States)

    John, David A.; du Bray, Edward A.; Henry, Christopher D.; Vikre, Peter


    Many epithermal gold-silver deposits are temporally and spatially associated with late Oligocene to Pliocene magmatism of the southern ancestral Cascade arc in western Nevada and eastern California. These deposits, which include both quartz-adularia (low- and intermediate-sulfidation; Comstock Lode, Tonopah, Bodie) and quartz-alunite (high-sulfidation; Goldfield, Paradise Peak) types, were major producers of gold and silver. Ancestral Cascade arc magmatism preceded that of the modern High Cascades arc and reflects subduction of the Farallon plate beneath North America. Ancestral arc magmatism began about 45 Ma, continued until about 3 Ma, and extended from near the Canada-United States border in Washington southward to about 250 km southeast of Reno, Nevada. The ancestral arc was split into northern and southern segments across an inferred tear in the subducting slab between Mount Shasta and Lassen Peak in northern California. The southern segment extends between 42°N in northern California and 37°N in western Nevada and was active from about 30 to 3 Ma. It is bounded on the east by the northeast edge of the Walker Lane. Ancestral arc volcanism represents an abrupt change in composition and style of magmatism relative to that in central Nevada. Large volume, caldera-forming, silicic ignimbrites associated with the 37 to 19 Ma ignimbrite flareup are dominant in central Nevada, whereas volcanic centers of the ancestral arc in western Nevada consist of andesitic stratovolcanoes and dacitic to rhyolitic lava domes that mostly formed between 25 and 4 Ma. Both ancestral arc and ignimbrite flareup magmatism resulted from rollback of the shallowly dipping slab that began about 45 Ma in northeast Nevada and migrated south-southwest with time. Most southern segment ancestral arc rocks have oxidized, high potassium, calc-alkaline compositions with silica contents ranging continuously from about 55 to 77 wt%. Most lavas are porphyritic and contain coarse plagioclase

  20. U-Pb LA-SF-ICP-MS zircon geochronology of the Serbo-Macedonian Massif, Greece: palaeotectonic constraints for Gondwana-derived terranes in the Eastern Mediterranean (United States)

    Meinhold, Guido; Kostopoulos, Dimitrios; Frei, Dirk; Himmerkus, Felix; Reischmann, Thomas


    The Pirgadikia Terrane in northern Greece forms tectonic inliers within the Vardar suture zone bordering the Serbo-Macedonian Massif to the southwest. It comprises Cadomian basement rocks of volcanic-arc origin and very mature quartz-rich metasedimentary rocks. U-Pb laser ablation sector-field inductively-coupled plasma mass spectrometry analyses of detrital zircons from the latter reveal a marked input from a Cadomian-Pan-African source with minor contribution from Mesoproterozoic, Palaeoproterozoic and Archaean sources. The metasedimentary rocks are correlated with Ordovician overlap sequences at the northern margin of Gondwana on the basis of their maturity and zircon age spectra. The Pirgadikia Terrane can be best interpreted as a peri-Gondwana terrane of Avalonian origin, which was situated close to the Cadomian terranes in the Late Neoproterozoic-Early Palaeozoic, very much like the Istanbul Terrane. The second unit investigated is the Vertiskos Terrane, which constitutes the major part of the Serbo-Macedonian Massif in Greece. It comprises predominantly igneous rocks of Silurian age and minor metasedimentary rocks of unknown age and provenance. U-Pb analyses of detrital zircons from a garnetiferous mica schist of the Vertiskos Terrane indicate derivation from 550 to 1,150 Ma-old source rocks with a major Cadomian peak. This, combined with minor input of >1,950 Ma-old zircons and the absence of ages between ca. 1.2 and 1.7 Ga suggests a NW Africa source. The protolith age of the garnetiferous mica schist is presumably Early Ordovician. One sample of garnet-bearing biotite gneiss, interpreted as meta-igneous rock, comprises predominantly subhedral zircons of igneous origin with late Middle Ordovician to Silurian ages. We suggest that the rock association of the Vertiskos Terrane is part of an ancient active-margin succession of the Hun superterrane, comparable to successions of the Austro- and Intra-Alpine Terranes. The new data of this study provide evidence

  1. Obesity and Native Hawaiians/Pacific Islanders (United States)

    ... Population Profiles > Native Hawaiian/Other Pacific Islander > Obesity Obesity and Native Hawaiians/Pacific Islanders Native Hawaiians/Pacific ... youthonline . [Accessed 05/25/2016] HEALTH IMPACT OF OBESITY More than 80 percent of people with type ...

  2. Asthma and Native Hawaiians/Pacific Islanders (United States)

    ... Population Profiles > Native Hawaiian/Other Pacific Islander > Asthma Asthma and Native Hawaiians/Pacific Islanders Native Hawaiians/Pacific Islanders are 70 percent more likely to have asthma as non-Hispanic whites. National data for this ...

  3. Intersection of opposing pedagogical frameworks: Native Hawaiian ancestral stories and scientific inquiry in a high school science class (United States)

    Kanahele-Mossman, Huihui

    Inquiry is defined as "an examination into facts and principles." In science education science inquiry is a process through which important discoveries are made by students through scientific methodology. The most important step in this process is forming the right question. The questions formed by students are usually the wrong questions which deem the remainder of the inquiry process impotent. This research will look at the pedagogy of ancestral stories for a solution. For the researcher, ancestral stories were a source of wonderment and learning not only from the lessons the stories revealed but mainly from the questions that still remained after the stories were told. Questions such as "why does the eel only swim near that part?", or "why does the story only talk about the uhu?" are examples of questions that remained after experiencing an ancestral narrative. The research questions were composed for the purpose of finding compatibility between the two pedagogies. The first research question which reads "how can Native Hawaiian ancestral stories encourage an increased level of student driven interactions at all levels of feedback from Native Hawaiian students in science classroom" focuses the research on the level of student feedback that initiate questions. Question two which reads "how can teachers of Native Hawaiian students facilitate the construction of science inquiry projects from ancestral stories" addresses the skill of the teacher and imbeds the concept of pedagogical knowledge into the literature. The last research question "how do analysis and discussion of the stories connect Native Hawaiian students to their ancestral intelligence" examines the role of identity and identity to ancestral intelligence. The method intended for this research was Grounded theory which allows the researcher to develop principles, concepts and theories based on the data presented. Another method utilized in this research is an undocumented but culturally imbedded method

  4. Modelling the ancestral sequence distribution and model frequencies in context-dependent models for primate non-coding sequences

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    Baele Guy


    Full Text Available Abstract Background Recent approaches for context-dependent evolutionary modelling assume that the evolution of a given site depends upon its ancestor and that ancestor's immediate flanking sites. Because such dependency pattern cannot be imposed on the root sequence, we consider the use of different orders of Markov chains to model dependence at the ancestral root sequence. Root distributions which are coupled to the context-dependent model across the underlying phylogenetic tree are deemed more realistic than decoupled Markov chains models, as the evolutionary process is responsible for shaping the composition of the ancestral root sequence. Results We find strong support, in terms of Bayes Factors, for using a second-order Markov chain at the ancestral root sequence along with a context-dependent model throughout the remainder of the phylogenetic tree in an ancestral repeats dataset, and for using a first-order Markov chain at the ancestral root sequence in a pseudogene dataset. Relaxing the assumption of a single context-independent set of independent model frequencies as presented in previous work, yields a further drastic increase in model fit. We show that the substitution rates associated with the CpG-methylation-deamination process can be modelled through context-dependent model frequencies and that their accuracy depends on the (order of the Markov chain imposed at the ancestral root sequence. In addition, we provide evidence that this approach (which assumes that root distribution and evolutionary model are decoupled outperforms an approach inspired by the work of Arndt et al., where the root distribution is coupled to the evolutionary model. We show that the continuous-time approximation of Hwang and Green has stronger support in terms of Bayes Factors, but the parameter estimates show minimal differences. Conclusions We show that the combination of a dependency scheme at the ancestral root sequence and a context

  5. Evolução tectónica do Gondwana durante o Paleozóico; um processo crucial na evolução da Terra


    Dias, Rui; Schmitt, Renata


    Durante o Paleozóico a actuação de diversos ciclos de Wilson levaram, não só à unificação da Gondwana mas também da própria Pangeia. Se alguns destes ciclos são exclusivamente paleozóicos (é o caso do orógeno Varisco nos sectores setentrionais), outros resultam de processos extensivos iniciados no final do Neoproterozóico e cujas fases colisionais só ocorreram no Paleozóico inferior (e.g. orogenia Búzios - SE do Brasil). Neste simpósio serão abordados os processos e mecanismos associados à ev...

  6. Diachronism in the late Neoproterozoic-Cambrian arc-rift transition of North Gondwana: A comparison of Morocco and the Iberian Ossa-Morena Zone (United States)

    Álvaro, J. Javier; Bellido, Félix; Gasquet, Dominique; Pereira, M. Francisco; Quesada, Cecilio; Sánchez-García, Teresa


    In the northwestern border of the West African craton (North Gondwana), a transition from late Neoproterozoic subduction/collision to Cambrian rift processes was recorded in the Anti-Atlas (Morocco) and in the Ossa-Morena Zone (Iberia). Cambrian rifting affected both Pan-African and Cadomian basements in a stepwise and diachronous way. Subsequently, both areas evolved into a syn-rift margin episodically punctuated by uplift and tilting that precluded Furongian sedimentation. A comparison of sedimentary, volcanic and geodynamic evolution is made in the late Neoproterozoic (Pan-African and Cadomian) belts and Cambrian rifts trying to solve the apparent diachronous (SW-NE-trending) propagation of an early Palaeozoic rifting regime that finally led to the opening of the Rheic Ocean.

  7. The Gondwana Orogeny in northern North Patagonian Massif: Evidences from the Caita Có granite, La Seña and Pangaré mylonites, Argentina

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    Daniel A. Gregori


    Full Text Available Structural analyses in the northern part of the North Patagonia Massif, in the foliated Caita Có granite and in La Seña and Pangaré mylonites, indicate that the pluton was intruded as a sheet-like body into an opening pull-apart structure during the Gondwana Orogeny. Geochronological studies in the massif indicate a first, lower to middle Permian stage of regional deformation, related to movements during indentation tectonics, with emplacement of foliated granites in the western and central areas of the North Patagonian Massif. Between the upper Permian and lower Triassic, evidence indicates emplacement of undeformed granitic bodies in the central part of the North Patagonian Massif. A second pulse of deformation between the middle and upper Triassic is related to the emplacement of the Caita Có granite, the development of mylonitic belts, and the opening of the Los Menucos Basin. During this pulse of deformation, compression direction was from the eastern quadrant.

  8. Significance of transition between Talchir Formation and Karharbari Formation in Lower Gondwana basin evolution — A study in West Bokaro Coal basin, Jharkhand, India

    Indian Academy of Sciences (India)

    H N Bhattacharya; Abhijit Chakraborty; Biplab Bhattacharya


    Basal part of the Gondwana Supergroup represented by Talchir and Karharbari Formations (Permo-Carboniferous) records an abrupt change-over from glacio-marine to terrestrial fluviolacustrine depositional environment. The contact between the two is an unconformity. Facies analysis of the glacio-marine Talchir Formation reveals that basal glaciogenic and reworked glaciogenic sediments are buried under storm influenced inner and outer shelf sediments. Facies associations of the Karharbari Formation suggest deposition as fluvio-lacustrine deposits in fault-controlled troughs. An attempt has been made in this paper to explain the sedimentation pattern in Talchir and Karharbari basins, and the abrupt change-over from glacio-marine to terrestrial fluviolacustrine depositional environment in terms of glacio-isostacy.

  9. Elongation Factor-Tu (EF-Tu) proteins structural stability and bioinformatics in ancestral gene reconstruction (United States)

    Dehipawala, Sunil; Nguyen, A.; Tremberger, G.; Cheung, E.; Schneider, P.; Lieberman, D.; Holden, T.; Cheung, T.


    A paleo-experimental evolution report on elongation factor EF-Tu structural stability results has provided an opportunity to rewind the tape of life using the ancestral protein sequence reconstruction modeling approach; consistent with the book of life dogma in current biology and being an important component in the astrobiology community. Fractal dimension via the Higuchi fractal method and Shannon entropy of the DNA sequence classification could be used in a diagram that serves as a simple summary. Results from biomedical gene research provide examples on the diagram methodology. Comparisons between biomedical genes such as EEF2 (elongation factor 2 human, mouse, etc), WDR85 in epigenetics, HAR1 in human specificity, DLG1 in cognitive skill, and HLA-C in mosquito bite immunology with EF Tu DNA sequences have accounted for the reported circular dichroism thermo-stability data systematically; the results also infer a relatively less volatility geologic time period from 2 to 3 Gyr from adaptation viewpoint. Comparison to Thermotoga maritima MSB8 and Psychrobacter shows that Thermus thermophilus HB8 EF-Tu calibration sequence could be an outlier, consistent with free energy calculation by NUPACK. Diagram methodology allows computer simulation studies and HAR1 shows about 0.5% probability from chimp to human in terms of diagram location, and SNP simulation results such as amoebic meningoencephalitis NAF1 suggest correlation. Extensions to the studies of the translation and transcription elongation factor sequences in Megavirus Chiliensis, Megavirus Lba and Pandoravirus show that the studied Pandoravirus sequence could be an outlier with the highest fractal dimension and lowest entropy, as compared to chicken as a deviant in the DNMT3A DNA methylation gene sequences from zebrafish to human and to the less than one percent probability in computer simulation using the HAR1 0.5% probability as reference. The diagram methodology would be useful in ancestral gene

  10. Analysis on the reconstruction accuracy of the Fitch method for inferring ancestral states

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    Grünewald Stefan


    Full Text Available Abstract Background As one of the most widely used parsimony methods for ancestral reconstruction, the Fitch method minimizes the total number of hypothetical substitutions along all branches of a tree to explain the evolution of a character. Due to the extensive usage of this method, it has become a scientific endeavor in recent years to study the reconstruction accuracies of the Fitch method. However, most studies are restricted to 2-state evolutionary models and a study for higher-state models is needed since DNA sequences take the format of 4-state series and protein sequences even have 20 states. Results In this paper, the ambiguous and unambiguous reconstruction accuracy of the Fitch method are studied for N-state evolutionary models. Given an arbitrary phylogenetic tree, a recurrence system is first presented to calculate iteratively the two accuracies. As complete binary tree and comb-shaped tree are the two extremal evolutionary tree topologies according to balance, we focus on the reconstruction accuracies on these two topologies and analyze their asymptotic properties. Then, 1000 Yule trees with 1024 leaves are generated and analyzed to simulate real evolutionary scenarios. It is known that more taxa not necessarily increase the reconstruction accuracies under 2-state models. The result under N-state models is also tested. Conclusions In a large tree with many leaves, the reconstruction accuracies of using all taxa are sometimes less than those of using a leaf subset under N-state models. For complete binary trees, there always exists an equilibrium interval [a, b] of conservation probability, in which the limiting ambiguous reconstruction accuracy equals to the probability of randomly picking a state. The value b decreases with the increase of the number of states, and it seems to converge. When the conservation probability is greater than b, the reconstruction accuracies of the Fitch method increase rapidly. The reconstruction

  11. Paleomagnetic data support Early Permian age for the Abor Volcanics in the lower Siang Valley, NE India: Significance for Gondwana-related break-up models (United States)

    Ali, Jason R.; Aitchison, Jonathan C.; Chik, Sam Y. S.; Baxter, Alan T.; Bryan, Scott E.


    Confusion exists as to the age of the Abor Volcanics of NE India. Some consider the unit to have been emplaced in the Early Permian, others the Early Eocene, a difference of ˜230 million years. The divergence in opinion is significant because fundamentally different models explaining the geotectonic evolution of India depend on the age designation of the unit. Paleomagnetic data reported here from several exposures in the type locality of the formation in the lower Siang Valley indicate that steep dipping primary magnetizations (mean = 72.7 ± 6.2°, equating to a paleo-latitude of 58.1°) are recorded in the formation. These are only consistent with the unit being of Permian age, possibly Artinskian based on a magnetostratigraphic argument. Plate tectonic models for this time consistently show the NE corner of the sub-continent >50°S; in the Early Eocene it was just north of the equator, which would have resulted in the unit recording shallow directions. The mean declination is counter-clockwise rotated by ˜94°, around half of which can be related to the motion of the Indian block; the remainder is likely due local Himalayan-age thrusting in the Eastern Syntaxis. Several workers have correlated the Abor Volcanics with broadly coeval mafic volcanic suites in Oman, NE Pakistan-NW India and southern Tibet-Nepal, which developed in response to the Cimmerian block peeling-off eastern Gondwana in the Early-Middle Permian, but we believe there are problems with this model. Instead, we suggest that the Abor basalts relate to India-Antarctica/India-Australia extension that was happening at about the same time. Such an explanation best accommodates the relevant stratigraphical and structural data (present-day position within the Himalayan thrust stack), as well as the plate tectonic model for Permian eastern Gondwana.

  12. Cambrian rift-related magmatism in the Ossa-Morena Zone (Iberian Massif): Geochemical and geophysical evidence of Gondwana break-up (United States)

    Sarrionandia, F.; Carracedo Sánchez, M.; Eguiluz, L.; Ábalos, B.; Rodríguez, J.; Pin, C.; Gil Ibarguchi, J. I.


    Volcanic rocks of Cambrian age from Zafra (Ossa-Morena Zone, Iberian Massif) are the result of rift processes that affected Cadomian arc units accreted to the NW edge of Gondwana during the Neoproterozoic-Early Cambrian transition. Tephrite to rhyolite volcanics define an alkaline transitional association (Coombs type). Basic-ultrabasic rocks exhibit typical alkaline REE-patterns, strongly enriched in LREE with respect to HREE. Two parental magmas are identified, one with a mantle signature, lack of Nb negative anomaly and εNd500Ma + 3.8 to + 4.2; another with crustal contribution, minor Nb negative anomaly and εNd500Ma + 0.8 to + 1.8. Intermediate-acid rocks show variable REE fractionation and share geochemical characteristics of both basic-ultrabasic groups with restricted εNd500Ma + 2.2 to 3.1 and general absence of Nb negative anomaly. Basic-ultrabasic melts resulted from different amounts of partial melting of a homogeneous source and segregation at the garnet-spinel transition zone. We argue that the "Hales transition" recently recognized in reflection seismic experiments of SW Iberia might image such a source region. Mantle-derived magmas ponded at the base of the crust and weakly interacted with crustal rocks/melts, whilst intermediate-acid rocks were generated by plagioclase ± clinopyroxene ± amphibole fractionation. Melt ascent took place through fractures, with limited crustal interaction. Based upon the new geochemical results and complementary cartographic and geophysical data, a model is presented for the Cambrian break-up of North Gondwana due to magma ascent from the mantle.

  13. Early Cambrian granitoids of North Gondwana margin in the transition from a convergent setting to intra-continental rifting (Ossa-Morena Zone, SW Iberia) (United States)

    Sánchez-García, T.; Pereira, M. F.; Bellido, F.; Chichorro, M.; Silva, J. B.; Valverde-Vaquero, P.; Pin, Ch.; Solá, A. R.


    Two distinct Cambrian magmatic pulses are recognized in the Ossa-Morena Zone (SW Iberia): an early rift-(ER) and a main rift-related event. This Cambrian magmatism is related to intra-continental rifting of North Gondwana that is thought to have culminated in the opening of the Rheic Ocean in Lower Ordovician times. New data of whole-rock geochemistry (19 samples), Sm-Nd-Sr isotopes (4 samples) and ID-TIMS U-Pb zircon geochronology (1 sample) of the Early Cambrian ER plutonic rocks of the Ossa-Morena Zone are presented in this contribution. The ER granitoids (Barreiros, Barquete, Calera, Salvatierra de los Barros and Tablada granitoid Massifs) are mostly peraluminous granites. The Sm-Nd isotopic data show moderate negative ɛNdt values ranging from -3.5 to +0.1 and TDM ages greatly in excess of emplacement ages. Most ER granitoids are crustal melts. However, a subset of samples shows a transitional anorogenic alkaline tendency, together with more primitive isotopic signatures, documenting the participation of lower crust or mantle-derived sources and suggesting a local transient advanced stage of rifting. The Barreiros granitoid is intrusive into the Ediacaran basement of the Ossa-Morena Zone (Série Negra succession) and has yielded a crystallization age of 524.7 ± 0.8 Ma consistent with other ages of ER magmatic pulse. This age: (1) constrains the age of the metamorphism developed in the Ediacaran back-arc basins before the intrusion of granites and (2) defines the time of the transition from the Ediacaran convergent setting to the Lower Cambrian intra-continental rifting in North Gondwana.

  14. A study of the distribution of ice sheets on Gondwana Supercontinent in Paleozoic%冈瓦纳大陆古生代冰盖分布研究

    Institute of Scientific and Technical Information of China (English)

    王洪浩; 李江海; 李维波; 周肖贝; 马丽亚; 刘仲兰


    In this study, the authors reconstructed the distribution of ice sheets on Gondwana Supercontinent in Paleozoic based on the methods of stratigraphic correlation and paleomagnetism. By studying the Paleozoic glacier deposits on the major plates of Gondwana, the authors have reached the conclusion that three major glacial events occurred on Gondwana Supercontinent in Paleozoic, which included (1) Late Ordovician-Early Silurian glacial event, (2) Late Devonian-Early Carboniferous glacial event, (3) the end of Late Carboniferous-Permian glacial event. The Late Ordovician-Early Silurian glacier event lasted a shorter period of time, and the glacier deposits were limitedly distributed on West Gondwana. Compared with the first glacier period, the ice sheets during the Late Devonian-Early Carboniferous glacier period were even smaller and mainly distributed in South America Plate, whereas the last glacial event lasted for the longest time and influenced the largest area, and the ice sheets were distributed on all the major plates which constituted Gondwana Supercontinent. Furthermore, the centers of ice sheets in the three glacial events were all close to the South Pole, but they were not completely coincident. It is thus held that the major factor affecting the distribution of ice sheets on Gondwana Supercontinent was the temperature. In addition, basin dynamics, topography, attributes of glacier and other specific factors could also affect the distribution of ice sheets. Combining the authors’field work in Baoshan Block with achievements of other researchers, the authors have reached the conclusion that only the Late Carboniferous-Permian glacial event had an effect on China’s blocks, and mainly affected the blocks in Southwest China, including Baoshan Block, Tengchong Block, Lhasa Block and Qiangtang Block.%提基于冈瓦纳大陆主要板块冰川沉积地层的对比,并结合古地磁方法对冈瓦纳大陆古生代主要冰期的冰盖分布范围进行再

  15. Ancestral feeding state of ruminants reconsidered: earliest grazing adaptation claims a mixed condition for Cervidae

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    Azanza Beatriz


    Full Text Available Abstract Background Specialised leaf-eating is almost universally regarded as the ancestral state of all ruminants, yet little evidence can be cited in support of this assumption, apart from the fact that all early ruminants had low crowned cheek teeth. Instead, recent years have seen the emergence evidence contradicting the conventional view that low tooth crowns always indicate leaf-eating and high tooth crowns grass-eating. Results Here we report the results of two independent palaeodietary reconstructions for one of the earliest deer, Procervulus ginsburgi from the Early Miocene of Spain, suggesting that despite having lower tooth crowns than any living ruminant, this species included a significant proportion of grass in its diet. Conclusion The phylogenetic distribution of feeding styles strongly supports that leaf-grass mixed feeding was the original feeding style of deer, and that later dietary specialization on leaves or grass occurred independently in several lineages. Evidence for other ruminant clades suggests that facultative mixed feeding may in fact have been the primitive dietary state of the Ruminantia, which would have been morphologically expressed only under specific environmental factors.

  16. A PCA-based method for ancestral informative markers selection in structured populations

    Institute of Scientific and Technical Information of China (English)


    Identification of population structure can help trace population histories and identify disease genes. Structured association (SA) is a commonly used approach for population structure identification and association mapping. A major issue with SA is that its performance greatly depends on the informa-tiveness and the numbers of ancestral informative markers (AIMs). Present major AIM selection meth-ods mostly require prior individual ancestry information, which is usually not available or uncertain in practice. To address this potential weakness, we herein develop a novel approach for AIM selection based on principle component analysis (PCA), which does not require prior ancestry information of study subjects. Our simulation and real genetic data analysis results suggest that, with equivalent AIMs, PCA-based selected AIMs can significantly increase the accuracy of inferred individual ancestries compared with traditionally randomly selected AIMs. Our method can easily be applied to whole genome data to select a set of highly informative AIMs in population structure, which can then be used to identify potential population structure and correct possible statistical biases caused by population stratification.

  17. Anomalously high variation in postnatal development is ancestral for dinosaurs but lost in birds. (United States)

    Griffin, Christopher T; Nesbitt, Sterling J


    Compared with all other living reptiles, birds grow extremely fast and possess unusually low levels of intraspecific variation during postnatal development. It is now clear that birds inherited their high rates of growth from their dinosaurian ancestors, but the origin of the avian condition of low variation during development is poorly constrained. The most well-understood growth trajectories of later Mesozoic theropods (e.g., Tyrannosaurus, Allosaurus) show similarly low variation to birds, contrasting with higher variation in extant crocodylians. Here, we show that deep within Dinosauria, among the earliest-diverging dinosaurs, anomalously high intraspecific variation is widespread but then is lost in more derived theropods. This style of development is ancestral for dinosaurs and their closest relatives, and, surprisingly, this level of variation is far higher than in living crocodylians. Among early dinosaurs, this variation is widespread across Pangaea in the Triassic and Early Jurassic, and among early-diverging theropods (ceratosaurs), this variation is maintained for 165 million years to the end of the Cretaceous. Because the Late Triassic environment across Pangaea was volatile and heterogeneous, this variation may have contributed to the rise of dinosaurian dominance through the end of the Triassic Period.

  18. Bacterial community composition and diversity in an ancestral ant fungus symbiosis. (United States)

    Kellner, Katrin; Ishak, Heather D; Linksvayer, Timothy A; Mueller, Ulrich G


    Fungus-farming ants (Hymenoptera: Formicidae, Attini) exhibit some of the most complex microbial symbioses because both macroscopic partners (ants and fungus) are associated with a rich community of microorganisms. The ant and fungal microbiomes are thought to serve important beneficial nutritional and defensive roles in these symbioses. While most recent research has investigated the bacterial communities in the higher attines (e.g. the leaf-cutter ant genera Atta and Acromyrmex), which are often associated with antibiotic-producing Actinobacteria, very little is known about the microbial communities in basal lineages, labeled as 'lower attines', which retain the ancestral traits of smaller and more simple societies. In this study, we used 16S amplicon pyrosequencing to characterize bacterial communities of the lower attine ant Mycocepurus smithii among seven sampling sites in central Panama. We discovered that ant and fungus garden-associated microbiota were distinct from surrounding soil, but unlike the situation in the derived fungus-gardening ants, which show distinct ant and fungal microbiomes, microbial community structure of the ants and their fungi were similar. Another surprising finding was that the abundance of actinomycete bacteria was low and instead, these symbioses were characterized by an abundance of Lactobacillus and Pantoea bacteria. Furthermore, our data indicate that Lactobacillus strains are acquired from the environment rather than acquired vertically.

  19. Mouthparts of the Burgess Shale fossils Odontogriphus and Wiwaxia: implications for the ancestral molluscan radula. (United States)

    Smith, Martin R


    The Middle Cambrian lophotrochozoans Odontogriphus omalus and Wiwaxia corrugata have been interpreted as stem-group members of either the Mollusca, the Annelida, or a group containing Mollusca + Annelida. The case for each classification rests on the organisms' unusual mouthparts, whose two to three tooth-rows resemble both the molluscan radula and the jaws of certain annelid worms. Despite their potential significance, these mouthparts have not previously been described in detail. This study examined the feeding apparatuses of over 300 specimens from the 505-million-year-old Burgess Shale, many of which were studied for the first time. Rather than denticulate plates, each tooth row comprises a single axial tooth that is flanked on each side by eight to 16 separate shoehorn-shaped teeth. Tooth rows sat on a grooved basal tongue, and two large lobes flanked the apparatus. New observations--the shape, distribution and articulation of the individual teeth, and the mouthparts' mode of growth--are incompatible with an annelid interpretation, instead supporting a classification in Mollusca. The ancestral molluscan radula is best reconstructed as unipartite with a symmetrical medial tooth, and Odontogriphus and Wiwaxia as grazing deposit-feeders.

  20. DNA replication fidelity in Mycobacterium tuberculosis is mediated by an ancestral prokaryotic proofreader. (United States)

    Rock, Jeremy M; Lang, Ulla F; Chase, Michael R; Ford, Christopher B; Gerrick, Elias R; Gawande, Richa; Coscolla, Mireia; Gagneux, Sebastien; Fortune, Sarah M; Lamers, Meindert H


    The DNA replication machinery is an important target for antibiotic development in increasingly drug-resistant bacteria, including Mycobacterium tuberculosis. Although blocking DNA replication leads to cell death, disrupting the processes used to ensure replication fidelity can accelerate mutation and the evolution of drug resistance. In Escherichia coli, the proofreading subunit of the replisome, the ɛ exonuclease, is essential for high-fidelity DNA replication; however, we find that the corresponding subunit is completely dispensable in M. tuberculosis. Rather, the mycobacterial replicative polymerase DnaE1 itself encodes an editing function that proofreads DNA replication, mediated by an intrinsic 3'-5' exonuclease activity within its PHP domain. Inactivation of the DnaE1 PHP domain increases the mutation rate by more than 3,000-fold. Moreover, phylogenetic analysis of DNA replication proofreading in the bacterial kingdom suggests that E. coli is a phylogenetic outlier and that PHP domain-mediated proofreading is widely conserved and indeed may be the ancestral prokaryotic proofreader.

  1. The tendency to recreate ancestral CG dinucleotides in the human genome

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    Li Mingkun


    Full Text Available Abstract Background The CG dinucleotides are known to be deficient in the human genome, due to a high mutation rate from 5-methylated CG to TG and its complementary pair CA. Meanwhile, many cellular functions rely on these CG dinucleotides, such as gene expression controlled by cytosine methylation status. Thus, CG dinucleotides that provide essential functional substrates should be retained in genomes. How these two conflicting processes regarding the fate of CG dinucleotides - i.e., high mutation rate destroying CG dinucleotides, vs. functional processes that require their preservation remains an unsolved question. Results By analyzing the mutation and frequency spectrum of newly derived alleles in the human genome, a tendency towards generating more CGs was observed, which was mainly contributed by an excess number of mutations from CA/TG to CG. Simultaneously, we found a fixation preference for CGs derived from TG/CA rather than CGs generated by other dinucleotides. These tendencies were observed both in intergenic and genic regions. An analysis of Integrated Extended Haplotype Homozygosity provided no evidence of selection for newly derived CGs. Conclusions Ancestral CG dinucleotides that were subsequently lost by mutation tend to be recreated in the human genome, as indicated by a biased mutation and fixation pattern favoring new CGs that derived from TG/CA.

  2. Sandals as Icons: Representations in Ancestral Pueblo Rock Art and Effigies in Stone and Wood

    Directory of Open Access Journals (Sweden)

    Polly Schaafsma


    Full Text Available Dating the late 1000s to the mid-1200s CE, petroglyphs of sandal images are among others that distinguish ancient Pueblo rock art in the San Juan and Little Colorado River drainages on the Colorado Plateau from Ancestral Pueblo rock art elsewhere across the Southwest. The sandal “track” also has counterparts  as effigies in stone and wood often found in ceremonial contexts in Pueblo sites. These representations reflect the sandal styles of the times, both plain in contour and the jog-toed variety, the latter characterized by a projection where the little toe is positioned. These representations are both plain and patterned,  as are their material sandal counterparts. Their significance  as symbolic icons is their dominant aspect, and a ritual meaning is implicit.  As a component of a symbol system that was radically altered after 1300 CE, however, there is no ethnographic information that provides clues as to the sandal icon’s meaning. While there is no significant pattern of its associations with other symbolic content in the petroglyph panels, in some western San Juan sites cases a relationship to the hunt can be inferred. It is suggested that the track itself could refer to a deity, a mythological hero, or the carver ’s social identity. In conclusion, however, no clear meaning of the images themselves is forthcoming, and further research beckons.

  3. Ancestral gene duplication enabled the evolution of multifunctional cellulases in stick insects (Phasmatodea). (United States)

    Shelomi, Matan; Heckel, David G; Pauchet, Yannick


    The Phasmatodea (stick insects) have multiple, endogenous, highly expressed copies of glycoside hydrolase family 9 (GH9) genes. The purpose for retaining so many was unknown. We cloned and expressed the enzymes in transfected insect cell lines, and tested the individual proteins against different plant cell wall component poly- and oligosaccharides. Nearly all isolated enzymes were active against carboxymethylcellulose, however most could also degrade glucomannan, and some also either xylan or xyloglucan. The latter two enzyme groups were each monophyletic, suggesting the evolution of these novel substrate specificities in an early ancestor of the order. Such enzymes are highly unusual for Metazoa, for which no xyloglucanases had been reported. Phasmatodea gut extracts could degrade multiple plant cell wall components fully into sugar monomers, suggesting that enzymatic breakdown of plant cell walls by the entire Phasmatodea digestome may contribute to the Phasmatodea nutritional budget. The duplication and neofunctionalization of GH9s in the ancestral Phasmatodea may have enabled them to specialize as folivores and diverge from their omnivorous ancestors. The structural changes enabling these unprecedented activities in the cellulases require further study.

  4. Multiple chromosomal rearrangements structured the ancestral vertebrate Hox-bearing protochromosomes.

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    Vincent J Lynch


    Full Text Available While the proposal that large-scale genome expansions occurred early in vertebrate evolution is widely accepted, the exact mechanisms of the expansion--such as a single or multiple rounds of whole genome duplication, bloc chromosome duplications, large-scale individual gene duplications, or some combination of these--is unclear. Gene families with a single invertebrate member but four vertebrate members, such as the Hox clusters, provided early support for Ohno's hypothesis that two rounds of genome duplication (the 2R-model occurred in the stem lineage of extant vertebrates. However, despite extensive study, the duplication history of the Hox clusters has remained unclear, calling into question its usefulness in resolving the role of large-scale gene or genome duplications in early vertebrates. Here, we present a phylogenetic analysis of the vertebrate Hox clusters and several linked genes (the Hox "paralogon" and show that different phylogenies are obtained for Dlx and Col genes than for Hox and ErbB genes. We show that these results are robust to errors in phylogenetic inference and suggest that these competing phylogenies can be resolved if two chromosomal crossover events occurred in the ancestral vertebrate. These results resolve conflicting data on the order of Hox gene duplications and the role of genome duplication in vertebrate evolution and suggest that a period of genome reorganization occurred after genome duplications in early vertebrates.

  5. Ancestral origins of the prion protein gene D178N mutation in the Basque Country. (United States)

    Rodríguez-Martínez, Ana B; Barreau, Christian; Coupry, Isabelle; Yagüe, Jordi; Sánchez-Valle, Raquel; Galdós-Alcelay, Luis; Ibáñez, Agustín; Digón, Antón; Fernández-Manchola, Ignacio; Goizet, Cyril; Castro, Azucena; Cuevas, Nerea; Alvarez-Alvarez, Maite; de Pancorbo, Marian M; Arveiler, Benoît; Zarranz, Juan J


    Fatal familial insomnia (FFI) and familial Creutzfeldt-Jakob disease (fCJD) are familial prion diseases with autosomal dominant inheritance of the D178N mutation. FFI has been reported in at least 27 pedigrees around the world. Twelve apparently unrelated FFI and fCJD pedigrees with the characteristic D178N mutation have been reported in the Prion Diseases Registry of the Basque Country since 1993. The high incidence of familial prion diseases in this region may reflect a unique ancestral origin of the chromosome carrying this mutation. In order to investigate this putative founder effect, we developed "happy typing", a new approach to the happy mapping method, which consists of the physical isolation of large haploid genomic DNA fragments and their analysis by the Polymerase Chain Reaction in order to perform haplotypic analysis instead of pedigree analysis. Six novel microsatellite markers, located in a 150-kb genomic segment flanking the PRNP gene were characterized for typing haploid DNA fragments of 285 kb in size. A common haplotype was found in patients from the Basque region, strongly suggesting a founder effect. We propose that "happy typing" constitutes an efficient method for determining disease-associated haplotypes, since the analysis of a single affected individual per pedigree should provide sufficient evidence.

  6. Nondecarboxylating and decarboxylating isocitrate dehydrogenases: oxalosuccinate reductase as an ancestral form of isocitrate dehydrogenase. (United States)

    Aoshima, Miho; Igarashi, Yasuo


    Isocitrate dehydrogenase (ICDH) from Hydrogenobacter thermophilus catalyzes the reduction of oxalosuccinate, which corresponds to the second step of the reductive carboxylation of 2-oxoglutarate in the reductive tricarboxylic acid cycle. In this study, the oxidation reaction catalyzed by H. thermophilus ICDH was kinetically analyzed. As a result, a rapid equilibrium random-order mechanism was suggested. The affinities of both substrates (isocitrate and NAD+) toward the enzyme were extremely low compared to other known ICDHs. The binding activities of isocitrate and NAD+ were not independent; rather, the binding of one substrate considerably promoted the binding of the other. A product inhibition assay demonstrated that NADH is a potent inhibitor, although 2-oxoglutarate did not exhibit an inhibitory effect. Further chromatographic analysis demonstrated that oxalosuccinate, rather than 2-oxoglutarate, is the reaction product. Thus, it was shown that H. thermophilus ICDH is a nondecarboxylating ICDH that catalyzes the conversion between isocitrate and oxalosuccinate by oxidation and reduction. This nondecarboxylating ICDH is distinct from well-known decarboxylating ICDHs and should be categorized as a new enzyme. Oxalosuccinate-reducing enzyme may be the ancestral form of ICDH, which evolved to the extant isocitrate oxidative decarboxylating enzyme by acquiring higher substrate affinities.

  7. Anomalously high variation in postnatal development is ancestral for dinosaurs but lost in birds (United States)

    Griffin, Christopher T.; Nesbitt, Sterling J.


    Compared with all other living reptiles, birds grow extremely fast and possess unusually low levels of intraspecific variation during postnatal development. It is now clear that birds inherited their high rates of growth from their dinosaurian ancestors, but the origin of the avian condition of low variation during development is poorly constrained. The most well-understood growth trajectories of later Mesozoic theropods (e.g., Tyrannosaurus, Allosaurus) show similarly low variation to birds, contrasting with higher variation in extant crocodylians. Here, we show that deep within Dinosauria, among the earliest-diverging dinosaurs, anomalously high intraspecific variation is widespread but then is lost in more derived theropods. This style of development is ancestral for dinosaurs and their closest relatives, and, surprisingly, this level of variation is far higher than in living crocodylians. Among early dinosaurs, this variation is widespread across Pangaea in the Triassic and Early Jurassic, and among early-diverging theropods (ceratosaurs), this variation is maintained for 165 million years to the end of the Cretaceous. Because the Late Triassic environment across Pangaea was volatile and heterogeneous, this variation may have contributed to the rise of dinosaurian dominance through the end of the Triassic Period.

  8. Major Chromosomal Rearrangements Distinguish Willow and Poplar After the Ancestral "Salicoid" Genome Duplication. (United States)

    Hou, Jing; Ye, Ning; Dong, Zhongyuan; Lu, Mengzhu; Li, Laigeng; Yin, Tongming


    Populus (poplar) and Salix (willow) are sister genera in the Salicaceae family. In both lineages extant species are predominantly diploid. Genome analysis previously revealed that the two lineages originated from a common tetraploid ancestor. In this study, we conducted a syntenic comparison of the corresponding 19 chromosome members of the poplar and willow genomes. Our observations revealed that almost every chromosomal segment had a parallel paralogous segment elsewhere in the genomes, and the two lineages shared a similar syntenic pinwheel pattern for most of the chromosomes, which indicated that the two lineages diverged after the genome reorganization in the common progenitor. The pinwheel patterns showed distinct differences for two chromosome pairs in each lineage. Further analysis detected two major interchromosomal rearrangements that distinguished the karyotypes of willow and poplar. Chromosome I of willow was a conjunction of poplar chromosome XVI and the lower portion of poplar chromosome I, whereas willow chromosome XVI corresponded to the upper portion of poplar chromosome I. Scientists have suggested that Populus is evolutionarily more primitive than Salix. Therefore, we propose that, after the "salicoid" duplication event, fission and fusion of the ancestral chromosomes first give rise to the diploid progenitor of extant Populus species. During the evolutionary process, fission and fusion of poplar chromosomes I and XVI subsequently give rise to the progenitor of extant Salix species. This study contributes to an improved understanding of genome divergence after ancient genome duplication in closely related lineages of higher plants.

  9. Convergent evolution of caffeine in plants by co-option of exapted ancestral enzymes. (United States)

    Huang, Ruiqi; O'Donnell, Andrew J; Barboline, Jessica J; Barkman, Todd J


    Convergent evolution is a process that has occurred throughout the tree of life, but the historical genetic and biochemical context promoting the repeated independent origins of a trait is rarely understood. The well-known stimulant caffeine, and its xanthine alkaloid precursors, has evolved multiple times in flowering plant history for various roles in plant defense and pollination. We have shown that convergent caffeine production, surprisingly, has evolved by two previously unknown biochemical pathways in chocolate, citrus, and guaraná plants using either caffeine synthase- or xanthine methyltransferase-like enzymes. However, the pathway and enzyme lineage used by any given plant species is not predictable from phylogenetic relatedness alone. Ancestral sequence resurrection reveals that this convergence was facilitated by co-option of genes maintained over 100 million y for alternative biochemical roles. The ancient enzymes of the Citrus lineage were exapted for reactions currently used for various steps of caffeine biosynthesis and required very few mutations to acquire modern-day enzymatic characteristics, allowing for the evolution of a complete pathway. Future studies aimed at manipulating caffeine content of plants will require the use of different approaches given the metabolic and genetic diversity revealed by this study.

  10. Evolution of outer membrane beta-barrels from an ancestral beta beta hairpin. (United States)

    Remmert, M; Biegert, A; Linke, D; Lupas, A N; Söding, J


    Outer membrane beta-barrels (OMBBs) are the major class of outer membrane proteins from Gram-negative bacteria, mitochondria, and plastids. Their transmembrane domains consist of 8-24 beta-strands forming a closed, barrel-shaped beta-sheet around a central pore. Despite their obvious structural regularity, evidence for an origin by duplication or for a common ancestry has not been found. We use three complementary approaches to show that all OMBBs from Gram-negative bacteria evolved from a single, ancestral beta beta hairpin. First, we link almost all families of known single-chain bacterial OMBBs with each other through transitive profile searches. Second, we identify a clear repeat signature in the sequences of many OMBBs in which the repeating sequence unit coincides with the structural beta beta hairpin repeat. Third, we show that the observed sequence similarity between OMBB hairpins cannot be explained by structural or membrane constraints on their sequences. The third approach addresses a longstanding problem in protein evolution: how to distinguish between a very remotely homologous relationship and the opposing scenario of "sequence convergence." The origin of a diverse group of proteins from a single hairpin module supports the hypothesis that, around the time of transition from the RNA to the protein world, proteins arose by amplification and recombination of short peptide modules that had previously evolved as cofactors of RNAs.

  11. Transgenerational actions of environmental compounds on reproductive disease and identification of epigenetic biomarkers of ancestral exposures.

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    Mohan Manikkam

    Full Text Available Environmental factors during fetal development can induce a permanent epigenetic change in the germ line (sperm that then transmits epigenetic transgenerational inheritance of adult-onset disease in the absence of any subsequent exposure. The epigenetic transgenerational actions of various environmental compounds and relevant mixtures were investigated with the use of a pesticide mixture (permethrin and insect repellant DEET, a plastic mixture (bisphenol A and phthalates, dioxin (TCDD and a hydrocarbon mixture (jet fuel, JP8. After transient exposure of F0 gestating female rats during the period of embryonic gonadal sex determination, the subsequent F1-F3 generations were obtained in the absence of any environmental exposure. The effects on the F1, F2 and F3 generations pubertal onset and gonadal function were assessed. The plastics, dioxin and jet fuel were found to promote early-onset female puberty transgenerationally (F3 generation. Spermatogenic cell apoptosis was affected transgenerationally. Ovarian primordial follicle pool size was significantly decreased with all treatments transgenerationally. Differential DNA methylation of the F3 generation sperm promoter epigenome was examined. Differential DNA methylation regions (DMR were identified in the sperm of all exposure lineage males and found to be consistent within a specific exposure lineage, but different between the exposures. Several genomic features of the DMR, such as low density CpG content, were identified. Exposure-specific epigenetic biomarkers were identified that may allow for the assessment of ancestral environmental exposures associated with adult onset disease.

  12. Detection of Weakly Conserved Ancestral Mammalian RegulatorySequences by Primate Comparisons

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Qian-fei; Prabhakar, Shyam; Chanan, Sumita; Cheng,Jan-Fang; Rubin, Edward M.; Boffelli, Dario


    Genomic comparisons between human and distant, non-primatemammals are commonly used to identify cis-regulatory elements based onconstrained sequence evolution. However, these methods fail to detectcryptic functional elements, which are too weakly conserved among mammalsto distinguish from nonfunctional DNA. To address this problem, weexplored the potential of deep intra-primate sequence comparisons. Wesequenced the orthologs of 558 kb of human genomic sequence, coveringmultiple loci involved in cholesterol homeostasis, in 6 nonhumanprimates. Our analysis identified 6 noncoding DNA elements displayingsignificant conservation among primates, but undetectable in more distantcomparisons. In vitro and in vivo tests revealed that at least three ofthese 6 elements have regulatory function. Notably, the mouse orthologsof these three functional human sequences had regulatory activity despitetheir lack of significant sequence conservation, indicating that they arecryptic ancestral cis-regulatory elements. These regulatory elementscould still be detected in a smaller set of three primate speciesincluding human, rhesus and marmoset. Since the human and rhesus genomesequences are already available, and the marmoset genome is activelybeing sequenced, the primate-specific conservation analysis describedhere can be applied in the near future on a whole-genome scale, tocomplement the annotation provided by more distant speciescomparisons.

  13. Evolutionary Psychology: How Psychological Mechanisms Shaped by Natural Selection for Ancestral Environments Produce Current Behaviours

    Institute of Scientific and Technical Information of China (English)

    Charles Crawford


    The central purpose of this paper is to explain how Darwin's theory of evolution by natural selection can be used in understanding current human behaviour. First, Darwin's logic is briefly described. Development is an important issue when applying evolutionary theory to human behaviour. The notion of innate developmental orga-nization of psychological mechanisms is introduced. The possible social and political outcomes produced when differ-ent levels of innate developmental organization are paired with different beliefs about it are considered. The notion of psychological mechanisms as evolved adaptations is considered in some detail. Then I discuss different ways evo-htionists think about how genes are involved in the development of adaptations. The paper concludes with a frame-work for considering how ancestral adaptations function in current environments and outlines some ways of studying them. In China and many other parts of the world people desire a more harmonious society. Ⅰ hope that this paper will be of some small help in achieving this great task.

  14. A PCA-based method for ancestral informative markers selection in structured populations

    Institute of Scientific and Technical Information of China (English)

    ZHANG Feng; ZHANG Lei; DENG Hong-Wen


    Identification of population structure can help trace population histories and identify disease genes.Structured association (SA) is a commonly used approach for population structure identification and association mapping. A major issue with SA is that its performance greatly depends on the informativeness and the numbers of ancestral informative markers (AIMs). Present major AIM selection methods mostly require prior individual ancestry information, which is usually not available or uncertain in practice. To address this potential weakness, we herein develop a novel approach for AIM selection based on principle component analysis (PCA), which does not require prior ancestry information of study subjects. Our simulation and real genetic data analysis results suggest that, with equivalent AIMs,PCA-based selected AIMs can significantly increase the accuracy of inferred individual ancestries compared with traditionally randomly selected AIMs. Our method can easily be applied to whole genome data to select a set of highly informative AIMs in population structure, which can then be used to identify potential population structure and correct possible statistical biases caused by population stratification.

  15. 客家祠堂的文化内涵研究--以三明客家祠堂为例%Study on the Culture Connotation of Hakka Ancestral Hall---Taking Sanming Hakka Ancestral Hall as an Example

    Institute of Scientific and Technical Information of China (English)



    Hakka ancestral hall is the most important place of Hakka clan ancestors,and it is an emotion carrier of Hakka as well, which contains rich cultural connotation. Sanming,as an important part of Fujian,Guangdong and Jiangxi Hakka stronghold,has a large number of Hakka ancestral halls. The name、couplets and architectural pattern of Hakka ancestral hall reflect how deeply the con-cept of ancestor worship of Hakka is;The pedigree of a clan、temple monument and ancestral hall couplets reflect how difficult Hakka' s migration path is;Its ancestor's instruction and function reflect how strong Hakka's concept of farming-reading is;Its site selection and layout reflect how prosperous Feng Shui Culture in Hakka is. They are the windows through which we can know Hakka history and Hak-ka culture.%客家祠堂是客家宗族祭祖的首要重地,也是客家人的情感载体,蕴含着丰富的文化内涵。三明作为闽粤赣边客家大本营的重要地区,拥有大量的客家祠堂,其堂号、楹联、建筑格局反映了客家人崇祖观念之深;其族谱、祠碑、楹联反映了客家人移民道路之艰;其祖训、功能反映出客家人耕读思想之重;其选址、布局反映出客家人风水文化之盛。客家祠堂是研究与理解客家历史文化的重要窗口。

  16. JGOFS moves to the Pacific (United States)

    Livingston, Hugh D.

    A process study in the equatorial Pacific Ocean for 1991-1992 has been recommended as the next major field program of the U.S. Joint Global Ocean Flux Study. The study will be preceded by a planning workshop in spring 1990.The equatorial study was selected at the September meeting of the U.S. JGOFS Committee at the University of Hawaii. The committee reviewed progress made since the issuance of the U.S. Pacific Planning report (U.S. JGOFS Planning Report No. 9) and the recommendations from the Scientific Committee on Oceanic Research (SCOR) JGOFS Pacific Planning meeting, which was at the university two days earlier.

  17. Thermotolerant Yeast Strains Adapted by Laboratory Evolution Show Trade-Off at Ancestral Temperatures and Preadaptation to Other Stresses

    DEFF Research Database (Denmark)

    Caspeta, Luis; Nielsen, Jens


    . Thermotolerant yeast strains showed horizontal displacement of their thermal reaction norms to higher temperatures. Hence, their optimal and maximum growth temperatures increased by about 3°C, whereas they showed a growth trade-off at temperatures below 34°C. Computational analysis of the physical properties...... in the ancestral strain. The latter is an advantageous attribute for acquiring thermotolerance and correlates with the reduction of yeast functions associated with loss of respiration capacity. This trait caused glycerol overproduction that was associated with the growth trade-off at ancestral temperatures....... In combination with altered sterol composition of cellular membranes, glycerol overproduction was also associated with yeast osmotolerance and improved tolerance of high concentrations of glucose and ethanol. Our study shows that thermal adaptation of yeast is suitable for improving yeast resistance...

  18. Identification of a new Newcastle disease virus isolate from Indonesia represents an ancestral lineage of class II genotype XIII. (United States)

    Forrester, Naomi L; Widen, Steve G; Wood, Thomas G; Travassos da Rosa, Amelia P; Ksiazek, Thomas G; Vasilakis, Nikos; Tesh, Robert B


    An unknown virus was isolated from a mosquito pool collected in Jakarta during routine surveillance in 1979. Analysis of the sample using the Illumina platform resulted in the identification of a Newcastle disease virus (NDV) isolate. The sequence of the isolate indicated that it is an ancestral lineage of class II, genotype XIII. The source of the isolate is unusual, as newcastle disease virus is not believed to be vector-borne, although this mosquito pool was processed in a laboratory also handling samples for avian influenza surveillance and it is possible that this resulted in cross-contamination. This NDV isolate is still ancestral to most extant genotype XIII strains and provides a useful insight into historic NDV evolution.

  19. Thermal evolution of the Sisters shear zone, southern New Zealand; Formation of the Great South Basin and onset of Pacific-Antarctic spreading (United States)

    Kula, Joseph; Tulloch, Andy J.; Spell, Terry L.; Wells, Michael L.; Zanetti, Kathleen A.


    The separation of Zealandia from West Antarctica was the final stage in the Cretaceous breakup of the Gondwana Pacific margin. Continental extension resulting in formation of the Great South Basin and thinning of the Campbell Plateau leading to development of the Pacific-Antarctic spreading ridge was partially accommodated along the Sisters shear zone. This east-northeast striking brittle-ductile structure exposed along the southeast coast of Stewart Island, New Zealand, is a greenschist facies extensional shear zone that separates a hanging wall of chloritic, brecciated granites, and undeformed conglomerate from a footwall of mylonitic Carboniferous and Early Cretaceous granites. This complex structure exhibits bivergent kinematics and can be subdivided into a northern and southern segment. The 40Ar/39Ar thermochronology indicates that cooling of the shear zone footwall began at ˜94 Ma with accelerated cooling over the interval ˜89-82 Ma. Structural and thermochronological data indicate a spatial and temporal link between the Sisters shear zone, initial sedimentation within the offshore Great South Basin, extension of the Campbell Plateau, and initiation of the Pacific-Antarctic spreading ridge.

  20. Genotype-based ancestral background consistently predicts efficacy and side effects across treatments in CATIE and STAR*D.

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    Daniel E Adkins

    Full Text Available Only a subset of patients will typically respond to any given prescribed drug. The time it takes clinicians to declare a treatment ineffective leaves the patient in an impaired state and at unnecessary risk for adverse drug effects. Thus, diagnostic tests robustly predicting the most effective and safe medication for each patient prior to starting pharmacotherapy would have tremendous clinical value. In this article, we evaluated the use of genetic markers to estimate ancestry as a predictive component of such diagnostic tests. We first estimated each patient's unique mosaic of ancestral backgrounds using genome-wide SNP data collected in the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE (n = 765 and the Sequenced Treatment Alternatives to Relieve Depression (STAR*D (n = 1892. Next, we performed multiple regression analyses to estimate the predictive power of these ancestral dimensions. For 136/89 treatment-outcome combinations tested in CATIE/STAR*D, results indicated 1.67/1.84 times higher median test statistics than expected under the null hypothesis assuming no predictive power (p<0.01, both samples. Thus, ancestry showed robust and pervasive correlations with drug efficacy and side effects in both CATIE and STAR*D. Comparison of the marginal predictive power of MDS ancestral dimensions and self-reported race indicated significant improvements to model fit with the inclusion of MDS dimensions, but mixed evidence for self-reported race. Knowledge of each patient's unique mosaic of ancestral backgrounds provides a potent immediate starting point for developing algorithms identifying the most effective and safe medication for a wide variety of drug-treatment response combinations. As relatively few new psychiatric drugs are currently under development, such personalized medicine offers a promising approach toward optimizing pharmacotherapy for psychiatric conditions.

  1. Evolutionary site-number changes of ribosomal DNA loci during speciation: complex scenarios of ancestral and more recent polyploid events. (United States)

    Rosato, Marcela; Moreno-Saiz, Juan C; Galián, José A; Rosselló, Josep A


    Several genome duplications have been identified in the evolution of seed plants, providing unique systems for studying karyological processes promoting diversification and speciation. Knowledge about the number of ribosomal DNA (rDNA) loci, together with their chromosomal distribution and structure, provides clues about organismal and molecular evolution at various phylogenetic levels. In this work, we aim to elucidate the evolutionary dynamics of karyological and rDNA site-number variation in all known taxa of subtribe Vellinae, showing a complex scenario of ancestral and more recent polyploid events. Specifically, we aim to infer the ancestral chromosome numbers and patterns of chromosome number variation, assess patterns of variation of both 45S and 5S rDNA families, trends in site-number change of rDNA loci within homoploid and polyploid series, and reconstruct the evolutionary history of rDNA site number using a phylogenetic hypothesis as a framework. The best-fitting model of chromosome number evolution with a high likelihood score suggests that the Vellinae core showing x = 17 chromosomes arose by duplication events from a recent x = 8 ancestor. Our survey suggests more complex patterns of polyploid evolution than previously noted for Vellinae. High polyploidization events (6x, 8x) arose independently in the basal clade Vella castrilensis-V. lucentina, where extant diploid species are unknown. Reconstruction of ancestral rDNA states in Vellinae supports the inference that the ancestral number of loci in the subtribe was two for each multigene family, suggesting that an overall tendency towards a net loss of 5S rDNA loci occurred during the splitting of Vellinae ancestors from the remaining Brassiceae lineages. A contrasting pattern for rDNA site change in both paleopolyploid and neopolyploid species was linked to diversification of Vellinae lineages. This suggests dynamic and independent changes in rDNA site number during speciation processes and a

  2. [Evolutionary history of Metazoa, ancestral status of the bilateria clonal reproduction, and semicolonial origin of the mollusca]. (United States)

    Martynov, A V


    Evolutionary history of any metazoan group is a history of the entire ontogenetic cycles instead of separate stages and genes only. Ontogeny in the most objective way links two key components of the biological systematics: historically-independent characters attribution and phylogeny itself. A general theory encompassing "static" traditional taxonomy and dynamic evolutionary process, based on the ontogenetic transformation of the organisms' shape is suggested here to term as ontogenetic systematics. As an important practical implication of the ontogenetic systematics, a new model of the bilaterian metazoans evolution is suggested. The new model considers asexual clonal reproduction as a central feature of the ancestral ontogenetic cycles of basal Bilateria. The new scenario resolves several notable contradictions, e.g. morphological, ontogenetic and molecular similarities of Pogonophora, Vestimentifera, Phoronida simultaneously to protostomian Spiralia (Lophotrochozoa) and Deuterostomia. The suggested model implies individuation (possibly multiple) of ancestral semicolonial sedentary group as a major factor of the basal Bilateria diversification. In the late Ediacaran and early Cambrian thus existed ancestral bilaterian group that shared characters of both Spiralia and Deuterostomia and possessed polyp-shape body and cephalic secretory shield (like in modern Pterobranchia and Vestimentifera), that later on reduced in various lines. This ancestral taxon in rank of supraphylum is suggested to term as Carmaphora (shield-bearers). Presence of the enigmatic sedentary fossil of the genus Cloudina with vestimentiferan-like tubes and evident clonal reproduction already in the late Ediacaran, and most recent found of an unquestionable pterobranch already in the early Cambrian support the new model of Bilateria evolution.

  3. Effect of the assignment of ancestral CpG state on the estimation of nucleotide substitution rates in mammals

    Directory of Open Access Journals (Sweden)

    Keightley Peter D


    Full Text Available Abstract Background Molecular evolutionary studies in mammals often estimate nucleotide substitution rates within and outside CpG dinucleotides separately. Frequently, in alignments of two sequences, the division of sites into CpG and non-CpG classes is based simply on the presence or absence of a CpG dinucleotide in either sequence, a procedure that we refer to as CpG/non-CpG assignment. Although it likely that this procedure is biased, it is generally assumed that the bias is negligible if species are very closely related. Results Using simulations of DNA sequence evolution we show that assignment of the ancestral CpG state based on the simple presence/absence of the CpG dinucleotide can seriously bias estimates of the substitution rate, because many true non-CpG changes are misassigned as CpG. Paradoxically, this bias is most severe between closely related species, because a minimum of two substitutions are required to misassign a true ancestral CpG site as non-CpG whereas only a single substitution is required to misassign a true ancestral non-CpG site as CpG in a two branch tree. We also show that CpG misassignment bias differentially affects fourfold degenerate and noncoding sites due to differences in base composition such that fourfold degenerate sites can appear to be evolving more slowly than noncoding sites. We demonstrate that the effects predicted by our simulations occur in a real evolutionary setting by comparing substitution rates estimated from human-chimp coding and intronic sequence using CpG/non-CpG assignment with estimates derived from a method that is largely free from bias. Conclusion Our study demonstrates that a common method of assigning sites into CpG and non CpG classes in pairwise alignments is seriously biased and recommends against the adoption of ad hoc methods of ancestral state assignment.

  4. Estimating ancestral proportions in a multi-ethnic US sample: implications for studies of admixed populations

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    Levran Orna


    Full Text Available Abstract This study was designed to determine the ancestral composition of a multi-ethnic sample collected for studies of drug addictions in New York City and Las Vegas, and to examine the reliability of self-identified ethnicity and three-generation family history data. Ancestry biographical scores for seven clusters corresponding to world major geographical regions were obtained using STRUCTURE, based on genotypes of 168 ancestry informative markers (AIMs, for a sample of 1,291 African Americans (AA, European Americans (EA, and Hispanic Americans (HA along with data from 1,051 HGDP-CEPH ‘diversity panel’ as a reference. Self-identified ethnicity and family history data, obtained in an interview, were accurate in identifying the individual major ancestry in the AA and the EA samples (approximately 99% and 95%, respectively but were not useful for the HA sample and could not predict the extent of admixture in any group. The mean proportions of the combined clusters corresponding to European and Middle Eastern populations in the AA sample, revealed by AIMs analysis, were 0.13. The HA subjects, predominantly Puerto Ricans, showed a highly variable hybrid contribution pattern of clusters corresponding to Europe (0.27, Middle East (0.27, Africa (0.20, and Central Asia (0.14. The effect of admixture on allele frequencies is demonstrated for two single-nucleotide polymorphisms (118A > G, 17 C > T of the mu opioid receptor gene (OPRM1. This study reiterates the importance of AIMs in defining ancestry, especially in admixed populations.

  5. Does body posture influence hand preference in an ancestral primate model?

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    Leliveld Lisette


    Full Text Available Abstract Background The origin of human handedness and its evolution in primates is presently under debate. Current hypotheses suggest that body posture (postural origin hypothesis and bipedalism hypothesis have an important impact on the evolution of handedness in primates. To gain insight into the origin of manual lateralization in primates, we studied gray mouse lemurs, suggested to represent the most ancestral primate condition. First, we investigated hand preference in a simple food grasping task to explore the importance of hand usage in a natural foraging situation. Second, we explored the influence of body posture by applying a forced food grasping task with varying postural demands (sit, biped, cling, triped. Results The tested mouse lemur population did not prefer to use their hands alone to grasp for food items. Instead, they preferred to pick them up using a mouth-hand combination or the mouth alone. If mouth usage was inhibited, they showed an individual but no population level handedness for all four postural forced food grasping tasks. Additionally, we found no influence of body posture on hand preference in gray mouse lemurs. Conclusion Our results do not support the current theories of primate handedness. Rather, they propose that ecological adaptation indicated by postural habit and body size of a given species has an important impact on hand preference in primates. Our findings suggest that small-bodied, quadrupedal primates, adapted to the fine branch niche of dense forests, prefer mouth retrieval of food and are less manually lateralized than large-bodied species which consume food in a more upright, and less stable body posture.

  6. Identification of the ancestral killer immunoglobulin-like receptor gene in primates

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    Coggill Penny


    Full Text Available Abstract Background Killer Immunoglobulin-like Receptors (KIR are essential immuno-surveillance molecules. They are expressed on natural killer and T cells, and interact with human leukocyte antigens. KIR genes are highly polymorphic and contribute vital variability to our immune system. Numerous KIR genes, belonging to five distinct lineages, have been identified in all primates examined thus far and shown to be rapidly evolving. Since few KIR remain orthologous between species, with only one of them, KIR2DL4, shown to be common to human, apes and monkeys, the evolution of the KIR gene family in primates remains unclear. Results Using comparative analyses, we have identified the ancestral KIR lineage (provisionally named KIR3DL0 in primates. We show KIR3DL0 to be highly conserved with the identification of orthologues in human (Homo sapiens, common chimpanzee (Pan troglodytes, gorilla (Gorilla gorilla, rhesus monkey (Macaca mulatta and common marmoset (Callithrix jacchus. We predict KIR3DL0 to encode a functional molecule in all primates by demonstrating expression in human, chimpanzee and rhesus monkey. Using the rhesus monkey as a model, we further show the expression profile to be typical of KIR by quantitative measurement of KIR3DL0 from an enriched population of natural killer cells. Conclusion One reason why KIR3DL0 may have escaped discovery for so long is that, in human, it maps in between two related leukocyte immunoglobulin-like receptor clusters outside the known KIR gene cluster on Chromosome 19. Based on genomic, cDNA, expression and phylogenetic data, we report a novel lineage of immunoglobulin receptors belonging to the KIR family, which is highly conserved throughout 50 million years of primate evolution.

  7. Paraphyly of organelle DNAs in Cycas Sect. Asiorientales due to ancient ancestral polymorphisms

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    Hsu Tsai-Wen


    Full Text Available Abstract Background This study addresses the apportionment of genetic diversity between Cycas revoluta and C. taitungensis, species that constitute the section Asiorientales and represent a unique, basal lineage of the Laurasian genus Cycas. Fossil evidence indicates divergence of the section from the rest of Cycas at least 30 million years ago. Geographically, C. taitungensis is limited to Taiwan whereas C. revoluta is found in the Ryukyu Archipelago and on mainland China. Results The phylogenies of ribosomal ITS region of mtDNA and the intergenic spacer between atpB and rbcL genes of cpDNA were reconstructed. Phylogenetic analyses revealed paraphyly of both loci in the two species and also in the section Asiorientales. The lack of reciprocal monophyly between these long isolated sections is likely due to persistent shared ancestral polymorphisms. Molecular dating estimated that mt- and cp DNA lineages coalesced to the most recent common ancestors (TMRCA about 327 (mt and 204 MYA (cp, corresponding with the divergence of cycad sections in the Mesozoic. Conclusion Fates of newly derived mutations of cycads follow Klopfstein et al.'s surfing model where the majority of new mutations do not spread geographically and remain at low frequencies or are eventually lost by genetic drift. Only successful 'surfing mutations' reach very high frequencies and occupy a large portion of a species range. These mutations exist as dominant cytotypes across populations and species. Geographical subdivision is lacking in both species, even though recurrent gene flow by both pollen and seed is severely limited. In total, the contrasting levels between historical and ongoing gene flow, large population sizes, a long lifespan, and slow mutation rates in both organelle DNAs have all likely contributed to the unusually long duration of paraphyly in cycads.

  8. Regionalization of the shark hindbrain: a survey of an ancestral organization

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    Isabel eRodríguez-Moldes


    Full Text Available Cartilaginous fishes (chondrichthyans represent an ancient radiation of vertebrates currently considered the sister group of the group of gnathostomes with a bony skeleton that gave rise to land vertebrates. This out-group position makes chondrichthyans essential in assessing the ancestral organization of the brain of jawed vertebrates. To gain knowledge about hindbrain evolution we have studied its development in a shark, the lesser spotted dogfish Scyliorhinus canicula by analyzing the expression of some developmental genes and the origin and distribution of specific neuronal populations, which may help to identify hindbrain subdivisions and boundaries and the topology of specific cell groups. We have characterized three developmental periods that will serve as a framework to compare the development of different neuronal systems and may represent a suitable tool for comparing the absolute chronology of development among vertebrates. The expression patterns of Pax6, Wnt8 and Hoxa2 genes in early embryos of S. canicula showed close correspondence to what has been described in other vertebrates and helped to identify the anterior rhombomeres. Also in these early embryos, the combination of Pax6 with protein markers of migrating neuroblasts (DCX and early differentiating neurons (general: HuC/D; neuron type specific: GAD, the GABA synthesizing enzyme revealed the organization of S. canicula hindbrain in both transverse segmental units corresponding to visible rhombomeres and longitudinal columns. Later in development, when the interrhombomeric boundaries fade away, accurate information about S. canicula hindbrain subdivisions was achieved by comparing the expression patterns of Pax6 and GAD, serotonin (serotoninergic neurons, tyrosine hydroxylase (catecholaminergic neurons, choline acetyltransferase (cholinergic neurons and calretinin (a calcium-binding protein. The patterns observed revealed many topological correspondences with other vertebrates

  9. Streptococcus thermophilus Biofilm Formation: A Remnant Trait of Ancestral Commensal Life?

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    Benoit Couvigny

    Full Text Available Microorganisms have a long history of use in food production and preservation. Their adaptation to food environments has profoundly modified their features, mainly through genomic flux. Streptococcus thermophilus, one of the most frequent starter culture organisms consumed daily by humans emerged recently from a commensal ancestor. As such, it is a useful model for genomic studies of bacterial domestication processes. Many streptococcal species form biofilms, a key feature of the major lifestyle of these bacteria in nature. However, few descriptions of S. thermophilus biofilms have been reported. An analysis of the ability of a representative collection of natural isolates to form biofilms revealed that S. thermophilus was a poor biofilm producer and that this characteristic was associated with an inability to attach firmly to surfaces. The identification of three biofilm-associated genes in the strain producing the most biofilms shed light on the reasons for the rarity of this trait in this species. These genes encode proteins involved in crucial stages of biofilm formation and are heterogeneously distributed between strains. One of the biofilm genes appears to have been acquired by horizontal transfer. The other two are located in loci presenting features of reductive evolution, and are absent from most of the strains analyzed. Their orthologs in commensal bacteria are involved in adhesion to host cells, suggesting that they are remnants of ancestral functions. The biofilm phenotype appears to be a commensal trait that has been lost during the genetic domestication of S. thermophilus, consistent with its adaptation to the milk environment and the selection of starter strains for dairy fermentations.

  10. Streptococcus thermophilus Biofilm Formation: A Remnant Trait of Ancestral Commensal Life? (United States)

    Couvigny, Benoit; Thérial, Claire; Gautier, Céline; Renault, Pierre; Briandet, Romain; Guédon, Eric


    Microorganisms have a long history of use in food production and preservation. Their adaptation to food environments has profoundly modified their features, mainly through genomic flux. Streptococcus thermophilus, one of the most frequent starter culture organisms consumed daily by humans emerged recently from a commensal ancestor. As such, it is a useful model for genomic studies of bacterial domestication processes. Many streptococcal species form biofilms, a key feature of the major lifestyle of these bacteria in nature. However, few descriptions of S. thermophilus biofilms have been reported. An analysis of the ability of a representative collection of natural isolates to form biofilms revealed that S. thermophilus was a poor biofilm producer and that this characteristic was associated with an inability to attach firmly to surfaces. The identification of three biofilm-associated genes in the strain producing the most biofilms shed light on the reasons for the rarity of this trait in this species. These genes encode proteins involved in crucial stages of biofilm formation and are heterogeneously distributed between strains. One of the biofilm genes appears to have been acquired by horizontal transfer. The other two are located in loci presenting features of reductive evolution, and are absent from most of the strains analyzed. Their orthologs in commensal bacteria are involved in adhesion to host cells, suggesting that they are remnants of ancestral functions. The biofilm phenotype appears to be a commensal trait that has been lost during the genetic domestication of S. thermophilus, consistent with its adaptation to the milk environment and the selection of starter strains for dairy fermentations.

  11. The ancestral activation promiscuity of ADP-glucose pyrophosphorylases from oxygenic photosynthetic organisms

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    Kuhn Misty L


    Full Text Available Abstract Background ADP-glucose pyrophosphorylase (ADP-Glc PPase catalyzes the first committed step in the synthesis of glycogen in bacteria and starch in algae and plants. In oxygenic photosynthetic organisms, ADP-Glc PPase is mainly activated by 3-phosphoglycerate (3-PGA and to a lesser extent by other metabolites. In this work, we analyzed the activation promiscuity of ADP-Glc PPase subunits from the cyanobacterium Anabaena PCC 7120, the green alga Ostreococcus tauri, and potato (Solanum tuberosum tuber by comparing a specificity constant for 3-PGA, fructose-1,6-bisphosphate (FBP, fructose-6-phosphate, and glucose-6-phosphate. Results The 3-PGA specificity constant for the enzymes from Anabaena (homotetramer, O. tauri, and potato tuber was considerably higher than for other activators. O. tauri and potato tuber enzymes were heterotetramers comprising homologous small and large subunits. Conversely, the O. tauri small subunit (OtaS homotetramer was more promiscuous because its FBP specificity constant was similar to that for 3-PGA. To explore the role of both OtaS and OtaL (O. tauri large subunit in determining the specificity of the heterotetramer, we knocked out the catalytic activity of each subunit individually by site-directed mutagenesis. Interestingly, the mutants OtaSD148A/OtaL and OtaS/OtaLD171A had higher specificity constants for 3-PGA than for FBP. Conclusions After gene duplication, OtaS seemed to have lost specificity for 3-PGA compared to FBP. This was physiologically and evolutionarily feasible because co-expression of both subunits restored the specificity for 3-PGA of the resulting heterotetrameric wild type enzyme. This widespread promiscuity seems to be ancestral and intrinsic to the enzyme family. Its presence could constitute an efficient evolutionary mechanism to accommodate the ADP-Glc PPase regulation to different metabolic needs.

  12. Evolution of neural crest and placodes: amphioxus as a model for the ancestral vertebrate? (United States)

    Holland, L. Z.; Holland, N. D.


    Recent studies of protochordates (ascidian tunicates and amphioxus) have given insights into possible ancestors of 2 of the characteristic features of the vertebrate head: neural crest and placodes. The neural crest probably evolved from cells on either side of the neural plate-epidermis boundary in a protochordate ancestral to the vertebrates. In amphioxus, homologues of several vertebrate neural crest marker genes (BMP2/4, Pax3/7, Msx, Dll and Snail) are expressed at the edges of the neural plate and/or adjacent nonneural ectoderm. Some of these markers are also similarly expressed in tunicates. In protochordates, however, these cells, unlike vertebrate neural crest, neither migrate as individuals through embryonic tissues nor differentiate into a wide spectrum of cell types. Therefore, while the protochordate ancestor of the vertebrates probably had the beginnings of a genetic programme for neural crest formation, this programme was augmented in the earliest vertebrates to attain definitive neural crest. Clear homologues of vertebrate placodes are lacking in protochordates. However, both amphioxus and tunicates have ectodermal sensory cells. In tunicates these are all primary neurons, sending axons to the central nervous system, while in amphioxus, the ectodermal sensory cells include both primary neurons and secondary neurons lacking axons. Comparisons of developmental gene expression suggest that the anterior ectoderm in amphioxus may be homologous to the vertebrate olfactory placode, the only vertebrate placode with primary, not secondary, neurons. Similarly, biochemical, morphological and gene expression data suggest that amphioxus and tunicates also have homologues of the adenohypophysis, one of the few vertebrate structures derived from nonneurogenic placodes. In contrast, the origin of the other vertebrate placodes is very uncertain.

  13. Evidence-based green algal genomics reveals marine diversity and ancestral characteristics of land plants

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    van Baren, Marijke J.; Bachy, Charles; Reistetter, Emily Nahas; Purvine, Samuel O.; Grimwood, Jane; Sudek, Sebastian; Yu, Hang; Poirier, Camille; Deerinck, Thomas J.; Kuo, Alan; Grigoriev, Igor V.; Wong, Chee-Hong; Smith, Richard D.; Callister, Stephen J.; Wei, Chia-Lin; Schmutz, Jeremy; Worden, Alexandra Z.


    Prasinophytes are widespread marine green algae that are related to plants. Abundance of the genus Micromonas has reportedly increased in the Arctic due to climate-induced changes. Thus, studies of these organisms are important for marine ecology and understanding Virdiplantae evolution and diversification. We generated evidence-based Micromonas gene models using proteomics and RNA-Seq to improve prasinophyte genomic resources. First, sequences of four chromosomes in the 22 Mb Micromonas pusilla (CCMP1545) genome were finished. Comparison with the finished 21 Mb Micromonas commoda (RCC299) shows they share less than 8,142of ~10,000 protein-encoding genes, depending on the analysis method. Unlike RCC299 and other sequenced eukaryotes, CCMP1545 has two abundant repetitive intron types and a high percent (26%) GC splice donors. Micromonas has more genus-specific protein families (19%) than other genome sequenced prasinophytes (11%). Comparative analyses using predicted proteomes from other prasinophytes reveal proteins likely related to scale formation and ancestral photosynthesis. Our studies also indicate that peptidoglycan (PG) biosynthesis enzymes have been lost in multiple independent events in select prasinophytes and most plants. However, CCMP1545, polar Micromonas CCMP2099 and prasinophytes from other claasses retain the entire PG pathway, like moss and glaucophyte algae. Multiple vascular plants that share a unique bi-domain protein also have the pathway, except the Penicillin-Binding-Protein. Alongside Micromonas experiments using antibiotics that halt bacterial PG biosynthesis, the findings highlight unrecognized phylogenetic complexity in the PG-pathway retention and implicate a role in chloroplast structure of division in several extant Vridiplantae lineages. Extensive differences in gene loss and architecture between related prasinophytes underscore their extensive divergence. PG biosynthesis genes from the cyanobacterial endosymbiont that became the

  14. BAC libraries construction from the ancestral diploid genomes of the allotetraploid cultivated peanut

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    Chaine Christian


    Full Text Available Abstract Background Cultivated peanut, Arachis hypogaea is an allotetraploid of recent origin, with an AABB genome. In common with many other polyploids, it seems that a severe genetic bottle-neck was imposed at the species origin, via hybridisation of two wild species and spontaneous chromosome duplication. Therefore, the study of the genome of peanut is hampered both by the crop's low genetic diversity and its polyploidy. In contrast to cultivated peanut, most wild Arachis species are diploid with high genetic diversity. The study of diploid Arachis genomes is therefore attractive, both to simplify the construction of genetic and physical maps, and for the isolation and characterization of wild alleles. The most probable wild ancestors of cultivated peanut are A. duranensis and A. ipaënsis with genome types AA and BB respectively. Results We constructed and characterized two large-insert libraries in Bacterial Artificial Chromosome (BAC vector, one for each of the diploid ancestral species. The libraries (AA and BB are respectively c. 7.4 and c. 5.3 genome equivalents with low organelle contamination and average insert sizes of 110 and 100 kb. Both libraries were used for the isolation of clones containing genetically mapped legume anchor markers (single copy genes, and resistance gene analogues. Conclusion These diploid BAC libraries are important tools for the isolation of wild alleles conferring resistances to biotic stresses, comparisons of orthologous regions of the AA and BB genomes with each other and with other legume species, and will facilitate the construction of a physical map.

  15. Allelic lineages of the ficolin genes (FCNs are passed from ancestral to descendant primates.

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    Tina Hummelshøj

    Full Text Available The ficolins recognize carbohydrates and acetylated compounds on microorganisms and dying host cells and are able to activate the lectin pathway of the complement system. In humans, three ficolin genes have been identified: FCN1, FCN2 and FCN3, which encode ficolin-1, ficolin-2 and ficolin-3, respectively. Rodents have only two ficolins designated ficolin-A and ficolin-B that are closely related to human ficolin-1, while the rodent FCN3 orthologue is a pseudogene. Ficolin-2 and ficolin-3 have so far only been observed in humans. Thus, we performed a systematic investigation of the FCN genes in non-human primates. The exons and intron-exon boundaries of the FCN1-3 genes were sequenced in the following primate species: chimpanzee, gorilla, orangutan, rhesus macaque, cynomolgus macaque, baboon and common marmoset. We found that the exon organisation of the FCN genes was very similar between all the non-human primates and the human FCN genes. Several variations in the FCN genes were found in more than one primate specie suggesting that they were carried from one species to another including humans. The amino acid diversity of the ficolins among human and non-human primate species was estimated by calculating the Shannon entropy revealing that all three proteins are generally highly conserved. Ficolin-1 and ficolin-2 showed the highest diversity, whereas ficolin-3 was more conserved. Ficolin-2 and ficolin-3 were present in non-human primate sera with the same characteristic oligomeric structures as seen in human serum. Taken together all the FCN genes show the same characteristics in lower and higher primates. The existence of trans-species polymorphisms suggests that different FCN allelic lineages may be passed from ancestral to descendant species.


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    Jairzinho Francisco Panqueba Cifuentes


    Full Text Available Los juegos de pelota mesoamericanos son manifestaciones corporales que han sido exploradasprincipalmente desde perspectivas arqueológicas e históricas, pero también han sido retomadosdesde distintas iniciativas para ponerlos en práctica. Desde la frontera entre Estados Unidos conMéxico, pasando por distintos Estados del país “azteca”, son practicadas diferentes modalidades deeste juego. Sin embargo, decir que el chaaj en Mesoamérica es hoy en día una alternativa recreativay deportiva, es quedarse corto respecto a su ya demostrado potencial. La sacralidad manifestada através de los movimientos corporales está ofreciendo opciones de innovación en varios espacios de lassociedades actuales. En su dimensión ceremonial, revela una comunicación ancestral muy actual. Allíse ponen en juego los códices, las interpretaciones arqueológicas y los conocimientos territoriales depersonas sabedoras de las comunidades. En su dimensión lúdica, el juego reúne elementos culturales,deportivos y pedagógicos. Ha sido una práctica corporal, técnica y motora ejecutada constantementeen algunas regiones mexicanas y guatemaltecas. No obstante su antigüedad, en los últimos años seviene registrando una promoción inusitada, en medio de los actuales tiempos de cambio que fueronanunciados desde tiempos inmemoriales por los sabedores y las sabedoras mayas.

  17. Toxic and nontoxic components of botulinum neurotoxin complex are evolved from a common ancestral zinc protein

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    Inui, Ken [Department of Food and Cosmetic Science, Faculty of Bioindustry, Tokyo University of Agriculture, 196 Yasaka, Abashiri 099-2493 (Japan); Japan Society for the Promotion of Science, 1-8 Chiyoda-ku, Tokyo 102-8472 (Japan); Sagane, Yoshimasa [Department of Food and Cosmetic Science, Faculty of Bioindustry, Tokyo University of Agriculture, 196 Yasaka, Abashiri 099-2493 (Japan); Miyata, Keita [Department of Food and Cosmetic Science, Faculty of Bioindustry, Tokyo University of Agriculture, 196 Yasaka, Abashiri 099-2493 (Japan); Japan Society for the Promotion of Science, 1-8 Chiyoda-ku, Tokyo 102-8472 (Japan); Miyashita, Shin-Ichiro [Department of Food and Cosmetic Science, Faculty of Bioindustry, Tokyo University of Agriculture, 196 Yasaka, Abashiri 099-2493 (Japan); Suzuki, Tomonori [Department of Bacteriology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558 (Japan); Shikamori, Yasuyuki [Agilent Technologies International Japan, Ltd. Takaura-cho 9-1, Hachioji-shi, Tokyo 192-0033 (Japan); Ohyama, Tohru; Niwa, Koichi [Department of Food and Cosmetic Science, Faculty of Bioindustry, Tokyo University of Agriculture, 196 Yasaka, Abashiri 099-2493 (Japan); Watanabe, Toshihiro, E-mail: [Department of Food and Cosmetic Science, Faculty of Bioindustry, Tokyo University of Agriculture, 196 Yasaka, Abashiri 099-2493 (Japan)


    Highlights: Black-Right-Pointing-Pointer BoNT and NTNHA proteins share a similar protein architecture. Black-Right-Pointing-Pointer NTNHA and BoNT were both identified as zinc-binding proteins. Black-Right-Pointing-Pointer NTNHA does not have a classical HEXXH zinc-coordinating motif similar to that found in all serotypes of BoNT. Black-Right-Pointing-Pointer Homology modeling implied probable key residues involved in zinc coordination. -- Abstract: Zinc atoms play an essential role in a number of enzymes. Botulinum neurotoxin (BoNT), the most potent toxin known in nature, is a zinc-dependent endopeptidase. Here we identify the nontoxic nonhemagglutinin (NTNHA), one of the BoNT-complex constituents, as a zinc-binding protein, along with BoNT. A protein structure classification database search indicated that BoNT and NTNHA share a similar domain architecture, comprising a zinc-dependent metalloproteinase-like, BoNT coiled-coil motif and concanavalin A-like domains. Inductively coupled plasma-mass spectrometry analysis demonstrated that every single NTNHA molecule contains a single zinc atom. This is the first demonstration of a zinc atom in this protein, as far as we know. However, the NTNHA molecule does not possess any known zinc-coordinating motif, whereas all BoNT serotypes possess the classical HEXXH motif. Homology modeling of the NTNHA structure implied that a consensus K-C-L-I-K-X{sub 35}-D sequence common among all NTNHA serotype molecules appears to coordinate a single zinc atom. These findings lead us to propose that NTNHA and BoNT may have evolved distinct functional specializations following their branching out from a common ancestral zinc protein.

  18. Are Hox genes ancestrally involved in axial patterning? Evidence from the hydrozoan Clytia hemisphaerica (Cnidaria.

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    Roxane Chiori

    Full Text Available BACKGROUND: The early evolution and diversification of Hox-related genes in eumetazoans has been the subject of conflicting hypotheses concerning the evolutionary conservation of their role in axial patterning and the pre-bilaterian origin of the Hox and ParaHox clusters. The diversification of Hox/ParaHox genes clearly predates the origin of bilaterians. However, the existence of a "Hox code" predating the cnidarian-bilaterian ancestor and supporting the deep homology of axes is more controversial. This assumption was mainly based on the interpretation of Hox expression data from the sea anemone, but growing evidence from other cnidarian taxa puts into question this hypothesis. METHODOLOGY/PRINCIPAL FINDINGS: Hox, ParaHox and Hox-related genes have been investigated here by phylogenetic analysis and in situ hybridisation in Clytia hemisphaerica, an hydrozoan species with medusa and polyp stages alternating in the life cycle. Our phylogenetic analyses do not support an origin of ParaHox and Hox genes by duplication of an ancestral ProtoHox cluster, and reveal a diversification of the cnidarian HOX9-14 genes into three groups called A, B, C. Among the 7 examined genes, only those belonging to the HOX9-14 and the CDX groups exhibit a restricted expression along the oral-aboral axis during development and in the planula larva, while the others are expressed in very specialised areas at the medusa stage. CONCLUSIONS/SIGNIFICANCE: Cross species comparison reveals a strong variability of gene expression along the oral-aboral axis and during the life cycle among cnidarian lineages. The most parsimonious interpretation is that the Hox code, collinearity and conservative role along the antero-posterior axis are bilaterian innovations.

  19. Emergence, Retention and Selection: A Trilogy of Origination for Functional De Novo Proteins from Ancestral LncRNAs in Primates.

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    Jia-Yu Chen


    Full Text Available While some human-specific protein-coding genes have been proposed to originate from ancestral lncRNAs, the transition process remains poorly understood. Here we identified 64 hominoid-specific de novo genes and report a mechanism for the origination of functional de novo proteins from ancestral lncRNAs with precise splicing structures and specific tissue expression profiles. Whole-genome sequencing of dozens of rhesus macaque animals revealed that these lncRNAs are generally not more selectively constrained than other lncRNA loci. The existence of these newly-originated de novo proteins is also not beyond anticipation under neutral expectation, as they generally have longer theoretical lifespan than their current age, due to their GC-rich sequence property enabling stable ORFs with lower chance of non-sense mutations. Interestingly, although the emergence and retention of these de novo genes are likely driven by neutral forces, population genetics study in 67 human individuals and 82 macaque animals revealed signatures of purifying selection on these genes specifically in human population, indicating a proportion of these newly-originated proteins are already functional in human. We thus propose a mechanism for creation of functional de novo proteins from ancestral lncRNAs during the primate evolution, which may contribute to human-specific genetic novelties by taking advantage of existed genomic contexts.

  20. When ancestral heritage is a source of discomfort: culture, pre-object relatedness, and self-alienation. (United States)

    Kradin, Richard L


    The ancestral claims on an individual can evoke mental conflict when they involve separating from an ethnic group whose beliefs and customs are devalued by the dominant culture. However, these claims are engraved on the psyche early in development by caretakers to the level of pre-object relatedness, where contents and affect tones are implicit and may be unavailable for later psychoanalytical interventions. In addition, as the anthropologist Clifford Geertz notes, one's culture of origin precedes the development of psyche and creates its own set of claims that must be renegotiated when one encounters a different domain of cultural symbols, a confrontation that can produce psychological dissonance and self-alienation. In this paper, three cases are examined in which mental conflicts were evoked by attempts at divesting ancestral claims in response to conscious efforts to assimilate into the dominant culture. These patients suffered from separation guilt and unstable self-esteem and reported dream imagery suggesting psychological imbalance. The requirement to carefully delineate the ancestral claims on psyche as well as those contents and affects that may not be accessible to therapeutic intervention is emphasized, and the importance of compromise and acceptance with respect to the psychological demands of the unconscious are considered.

  1. Western Pacific Typhoon Aircraft Fixes (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Western Pacific typhoon aircraft reconnaissance data from the years 1946 - 1965 and 1978, excluding 1952, were transcribed from original documents, or copy of...

  2. April 2016 Pacific Southwest Newsletter (United States)

    EPA Pacific Southwest Newsletter for April 2016: University of Arizona Reduces Food Waste, Cleaning Up Underground Fuel Tanks in Fresno, The Argonaut Mine, Ensuring Clean Water in Nevada,Cleaning Up Groundwater in Whittier, California, and more!

  3. Wave energy: a Pacific perspective. (United States)

    Paasch, Robert; Ruehl, Kelley; Hovland, Justin; Meicke, Stephen


    This paper illustrates the status of wave energy development in Pacific rim countries by characterizing the available resource and introducing the region's current and potential future leaders in wave energy converter development. It also describes the existing licensing and permitting process as well as potential environmental concerns. Capabilities of Pacific Ocean testing facilities are described in addition to the region's vision of the future of wave energy.

  4. Palaeoenvironmental and geochemical approach of Archaeocyath-rich facies from Lower Cambrian of Western Gondwana margin at Central Iberian Zone (Urda, Toledo Mountains, Spain) (United States)

    Menéndez, Silvia; Rodríguez-Martínez, Marta; Moreno-Eris, Elena; Perejón, Antonio; Reitner, Joachim


    in Western Gondwana margin. Powdered microsamples have been analysed for their elemental and isotopic composition (δ13C values range from + 0.41 to + 3.05). Sulphur minerals and silicates where analyzed with XRD and wavelength-dispersive electron microprobe. Major elements were measured with ICP-OES and minor and trace elements were analyzed with ICP-MS. These are the first palaeontological, sedimetological, geochemical and isotopical data provided to reconstruct the depositional environment of these Archaeocyath-rich facies at the Western Gondwana margin. References Julivert, M., Fontboté, J.M., Ribeiro, A., Nabais Conde L.E. 1972. Mapa tectónico de la Península Ibérica y Baleares, Escala 1: 1.000.000, Memoria Explicativa [1974], 113 pp. Instituto Geológico y Minero de España. Perejón, A., Moreno-Eiris, E. 2006. Biostratigraphy and palaeobiography of the archaeocyaths on the south-western margin of Gondwana. Zeitschrift der Deutschen Gesellschaft für Geowissenschaften 157 (4): 611-627.

  5. Triassic synthems of southern South America (southwestern Gondwana) and the Western Caucasus (the northern Neotethys), and global tracing of their boundaries (United States)

    Ruban, Dmitry A.; Zerfass, Henrique; Pugatchev, Vladimir I.


    Global tracing of the key surfaces of Triassic deposits may contribute significantly to the understanding of the common patterns in their accumulation. We attempt to define synthems - disconformity-bounded sedimentary complexes - in the Triassic successions of southern South America (southwestern Gondwana, Brazil and Argentina) and the Western Caucasus (the northern Neotethys, Russia), and then to trace their boundaries in the adjacent regions and globally. In southern South America, a number of synthems have been recognized - the Cuyo Basin: the Río Mendoza-Cerro de las Cabras Synthem (Olenekian-Ladinian) and the Potrerillos-Cacheuta-Río Blanco Synthem (Carnian-Rhaetian); the Ischigualasto Basin: the Ischichuca-Los Rastros Synthem (Anisian-Ladinian) and the Ischigualasto-Los Colorados Synthem (Carnian-Rhaetian); the Chaco-Paraná Basin: the Sanga do Cabral Synthem (Induan), the Santa Maria 1 Synthem (Ladinian), the Santa Maria 2 Synthem (Carnian), and the Caturrita Synthem (Norian); western Argentina: the Talampaya Synthem (Lower Triassic) and the Tarjados Synthem (Olenekian?). In the Western Caucasus, three common synthems have been distinguished: WC-1 (Induan-Anisian), WC-2 (uppermost Anisian-Carnian), and WC-3 (Norian-lower Rhaetian). The lower boundary of WC-1 corresponds to a hiatus whose duration seems to be shorter than that previously postulated. The synthem boundaries that are common to southwestern Gondwana and the Western Caucasus lie close to the base and top of the Triassic. The Lower Triassic, Ladinian, and Upper Triassic disconformities are traced within the studied basins of southern South America, and the first two are also established in South Africa. The Upper Triassic disconformity is only traced within the entire Caucasus, whereas all synthem boundaries established in the Western Caucasus are traced partly within Europe. In general, the synthem boundaries recognized in southern South America and the Western Caucasus are correlated to the

  6. From source-to-sink: The Late Permian SW Gondwana paleogeography and sedimentary dispersion unraveled by a multi-proxy analysis (United States)

    Alessandretti, Luciano; Machado, Rômulo; Warren, Lucas Veríssimo; Assine, Mario Luis; Lana, Cristiano


    The Late Permian sedimentary succession of the Paraná Basin, southern Brazil, provide a valuable source of information about sediment provenance, tectonic processes and, consequently, the paleogeography of the southwestern Gondwana supercontinent. In order to understand the patterns of sedimentary dispersal and reconstruct the Late Permian source-to-sink dynamic, we report a complete series of U-Pb ages and Hf isotopic compositions of detrital zircons from the Rio do Rasto Formation sandstones allied with detailed paleocurrent and sedimentologic data. Our integrated provenance study reveals a consistent sediment transport from the south to the north and northwest. According to the evaluation of zircon ages and Hf isotopes, it was possible to determine four distinct source areas: (i) a distant Late Paleozoic active magmatic arc located in the southwestern Gondwana margin (i.e. Gondwanides Orogen), corresponding to the North Patagonian Massif; (ii) recycling of orthoquartzites from the uplifted Paleozoic Ventania Fold Belt and immature sandstones from the Claromecó Foreland Basin in central-eastern Argentina and the Silurian-Devonian successions of the southern Paraná Basin (central-northern Uruguay) and North Patagonian Massif; (iii) exhumed areas of the Archean-Paleoproterozoic basement and Neoproterozoic to Early Paleozoic mobile belts of the Damara in southwestern Africa and Ribeira Fold Belt in Uruguay and southern Brazil; and (iv) southeastward provenance of Grenvillian (1.2-1.0 Ga) zircons coming from the mafic to intermediate Mesoproterozoic igneous units of the Namaqua-Natal Belt in South Africa and Namibia. These data allow us to argue that sediments deposited in the Paraná Basin during the Late Permian come from both short- and long-distance source areas. In this context, an important population of Permian detrital zircons comes from the Gondwanides Orogen in the south, probably carried by transcontinental alluvial systems. Close to the source area

  7. Pacific Studies: Quo Vadis?

    Directory of Open Access Journals (Sweden)

    Anne Holden Rønning


    Full Text Available Looking back to the past this paper discusses why Pacific studies and in particular Australasian studies became an area of interest in tertiary education in Europe. What subject areas initiated these studies, and how do past legacies shape the present? With cutbacks in higher education over the past two decades the future of interdisciplinary studies and the humanities looks bleak. At the same time due to global business and increased political communication across borders there is a vibrant interest in and need for such studies among businesses and students. For most Europeans the literature of settler countries, with their European legacy, makes access to ways of thought and culture easier than studies of countries with other mythological backgrounds. In today’s multicultural environment such studies can provide knowledge for an understanding of other cultures and increase tolerance of the ‘other’. Area studies have relevance to our situation in Europe with increased migrancy, not least as a result of Schengen and EU regulations.

  8. A Common Ancestral Mutation in CRYBB3 Identified in Multiple Consanguineous Families with Congenital Cataracts.

    Directory of Open Access Journals (Sweden)

    Xiaodong Jiao

    report a common ancestral mutation in CRYBB3 associated with autosomal recessive congenital cataracts identified in four familial cases of Pakistani origin.

  9. Muscle fiber-type variation in lizards (Squamata) and phylogenetic reconstruction of hypothesized ancestral states. (United States)

    Bonine, Kevin E; Gleeson, Todd T; Garland, Theodore


    . Reconstruction of ancestral trait values by use of phylogenetically based statistical methods indicates especially large changes in fiber-type composition during the evolution of horned lizards.

  10. The African and Pacific Superplume Structures Constrained by Assembly and Breakup of Pangea (United States)

    Zhang, N.; Zhong, S.; Leng, W.; Li, Z.


    Seismic tomography studies indicate that the Earth’s mantle structure is characterized by African and Pacific seismically slow velocity anomalies (i.e., superplumes) and circum-Pacific seismically fast anomalies (i.e., a globally spherical harmonic degree-2 structure). McNamara and Zhong (2005) have demonstrated that the African and Pacific superplume structures result from dynamic interaction between mantle convection and surface plate motion history in the last 120 Ma. However, their models produce slightly stronger degree 3 structure than degree 2 near the CMB. Here, we construct a proxy model of plate motions for the African hemisphere for the last 450 Ma since the Early Paleozoic using the paleogeographic reconstruction of continents constrained by paleomagnetic and geological observations. Using this proxy model for plate motion history as the time-dependent surface boundary conditions for a 3-dimensional spherical model of thermochemical mantle convection, we calculate the present-day mantle structure and explore the evolution of mantle structures since the Early Paleozoic. Our model calculations reproduce well the present-day mantle structure including the African and Pacific superplumes. The power spectra of our calculated present-day temperature field shows that the strongest power occurs at degree 2 in the lower mantle while in the upper mantle the strongest power is at degree 3. The degree correlation between tomography model S20RTS and our calculated temperature field shows a high correlation at the degree 1 and degree 2 in the lower mantle while the upper mantle and the short wavelength structures do not correlate well. The summed degree correlation for the lower mantle shows a relatively good correlation for the bottom 300 km of the mantle but the correlation is significantly reduced at depth 600 km above the CMB. For the evolution of mantle structures, we focus on the evolution of the African superplume. Our results suggest that the mantle in the

  11. Reconstructed ancestral Myo-inositol-3-phosphate synthases indicate that ancestors of the Thermococcales and Thermotoga species were more thermophilic than their descendants.

    Directory of Open Access Journals (Sweden)

    Nicholas C Butzin

    Full Text Available The bacterial genomes of Thermotoga species show evidence of significant interdomain horizontal gene transfer from the Archaea. Members of this genus acquired many genes from the Thermococcales, which grow at higher temperatures than Thermotoga species. In order to study the functional history of an interdomain horizontally acquired gene we used ancestral sequence reconstruction to examine the thermal characteristics of reconstructed ancestral proteins of the Thermotoga lineage and its archaeal donors. Several ancestral sequence reconstruction methods were used to determine the possible sequences of the ancestral Thermotoga and Archaea myo-inositol-3-phosphate synthase (MIPS. These sequences were predicted to be more thermostable than the extant proteins using an established sequence composition method. We verified these computational predictions by measuring the activities and thermostabilities of purified proteins from the Thermotoga and the Thermococcales species, and eight ancestral reconstructed proteins. We found that the ancestral proteins from both the archaeal donor and the Thermotoga most recent common ancestor recipient were more thermostable than their descendants. We show that there is a correlation between the thermostability of MIPS protein and the optimal growth temperature (OGT of its host, which suggests that the OGT of the ancestors of these species of Archaea and the Thermotoga grew at higher OGTs than their descendants.

  12. Tropical Pacific Decadal Variability in Subsurface Temperature

    Institute of Scientific and Technical Information of China (English)

    LIU Qinyu; XU Lixiao; LU Jiuyou; WANG Qi


    The nature decadal variability of the equatorial Pacific subsurface temperature is examined in the control simulation with the Geophysical Fluid Dynamics Laboratory coupled model CM2.1.The dominant mode of the subsurface temperature variations in the equator Pacific features a 20-40 year period and is North-South asymmetric about the equator.Decadal variations of the thermocline are most pronounced in the southwest of the Tropical Pacific.Decadal variation of the north-south asymmetric Sea Surface wind in the tropical Pacific,especially in the South Pacific Convergence,is the dominant mechanism of the nature decadal variation of the subsurface temperature in the equatorial Pacific.

  13. La modernidad, el cuidado de la salud y la cultura ancestral.

    Directory of Open Access Journals (Sweden)

    Ana Cecilia Becerra


    Full Text Available La modernidad es tanto un período histórico como un concepto filosófico y sociológico que impuso la razón y el método formal sobre todos los actos políticos, sociales y epistemológicos de las distintas culturas del mundo. La modernidad se construyó en su momento sobre el imaginario de la superioridad europea1 y durante el período colonial fue la causante del proceso avasallador de exterminio y de desconocimiento de las sociedades y culturas indígenas de América. Ella, con sus valores patriarcales y formales, desplazó la ética del cuidado y del abrigo de los pueblos autóctonos imponiendo una lógica racional, calculadora e impersonal. Al desconocer y casi negar en su totalidad la cosmovisión ancestral de curar y cuidar, relegó los ejercicios profesionalizantes de la salud bajo el amparo de la mercantilización del capitalismo mundial integrado. La modernidad, desde el inicio y en la actualidad, ha impregnado la cultura de todos los pueblos y ha condicionado todos los actos académicos en las instituciones escolares y universitarias. La perpetuación de un modelo positivista y occidentalizado ha sido una constante en las aulas universitarias y en las disciplinas, sobre todo en las ciencias de la salud. Históricamente el conocimiento en salud ha sido construido con base en el enfoque positivista y la concepción biologista del proceso salud-enfermedad, lo cual lleva a una fragmentación del saber, disyunción del sujeto y el objeto en la producción del conocimiento, y a una incapacidad de asumir al ser humano en todas sus dimensiones, razón de ser de la acción en salud, como totalidad y unidad integral2. Este panorama aquí planteado deja un gran reto epistemológico a los profesionales y a los docentes de las ciencias de la salud en general y de enfermería en particular. Vista la enfermería desde la fundamentación del cuidado de la salud, no se puede descontextualizar ni escindir de nuestra propia cultura, pretendiendo

  14. La modernidad, el cuidado de la salud y la cultura ancestral

    Directory of Open Access Journals (Sweden)

    Ana Cecilia Becerra


    Full Text Available La modernidad es tanto un período histórico como un concepto filosófico y sociológico que impuso la razón y el método formal sobre todos los actos políticos, sociales y epistemológicos de las distintas culturas del mundo. La modernidad se construyó en su momento sobre el imaginario de la superioridad europea1 y durante el período colonial fue la causante del proceso avasallador de exterminio y de desconocimiento de las sociedades y culturas indígenas de América.Ella, con sus valores patriarcales y formales, desplazó la ética del cuidado y del abrigo de los pueblos autóctonos imponiendo una lógica racional, calculadora e impersonal. Al desconocer y casi negar en su totalidad la cosmovisión ancestral de curar y cuidar, relegó los ejercicios profesionalizantes de la salud bajo el amparo de la mercantilización del capitalismo mundial integrado.La modernidad, desde el inicio y en la actualidad, ha impregnado la cultura de todos los pueblos y ha condicionado todos los actos académicos en las instituciones escolares y universitarias. La perpetuación de un modelo positivista y occidentalizado ha sido una constante en las aulas universitarias y en las disciplinas, sobre todo en las ciencias de la salud. Históricamente el conocimiento en salud ha sido construido con base en el enfoque positivista y la concepción biologista del proceso salud-enfermedad, lo cual lleva a una fragmentación del saber, disyunción del sujeto y el objeto en la producción del conocimiento, y a una incapacidad de asumir al ser humano en todas sus dimensiones, razón de ser de la acción en salud, como totalidad y unidad integral2.Este panorama aquí planteado deja un gran reto epistemológico a los profesionales y a los docentes de las ciencias de la salud en general y de enfermería en particular. Vista la enfermería desde la fundamentación del cuidado de la salud, no se puede descontextualizar ni escindir de nuestra propia cultura, pretendiendo

  15. Paleomagnetism of Jurassic and Cretaceous rocks in central Patagonia: a key to constrain the timing of rotations during the breakup of southwestern Gondwana? (United States)

    Geuna, Silvana E.; Somoza, Rubén; Vizán, Haroldo; Figari, Eduardo G.; Rinaldi, Carlos A.


    A paleomagnetic study in Jurassic and Cretaceous rocks from the Cañadón Asfalto basin, central Patagonia, indicates the occurrence of about 25-30° clockwise rotation in Upper Jurassic-lowermost Cretaceous rocks, whereas the overlying mid-Cretaceous rocks do not show evidence of rotation. This constrains the tectonic rotation to be related to a major regional unconformity in Patagonia, which in turn seems to be close in time with the early opening of the South Atlantic Ocean. The sense and probably the timing of this rotation are similar to those of other paleomagnetically detected rotations in different areas of southwestern Gondwana, suggesting a possible relationship between these and major tectonic processes related with fragmentation of the supercontinent. On the other hand, the mid-Cretaceous rocks in the region yield a paleopole located at Lat. 87° South, Long. 159° East, A95=3.8°. This pole position is consistent with coeval high-quality paleopoles of other plates when transferred to South American coordinates, implying it is an accurate determination of the Aptian (circa 116 Ma) geomagnetic field in South America.

  16. Late-Proterozoic to Paleozoic history of the peri-Gondwana Calabria-Peloritani Terrane inferred from a review of zircon chronology. (United States)

    Fornelli, Annamaria; Micheletti, Francesca; Piccarreta, Giuseppe


    U-Pb analyses of zircon from ten samples of augen gneisses, eight mafic and intermediate metaigneous rocks and six metasediments from some tectonic domains along the Calabria-Peloritani Terrane (Southern Italy) contribute to knowledge of peri-Gondwanan evolution from Late-Proterozoic to Paleozoic times. All samples were equilibrated under amphibolite to granulite facies metamorphism during the Variscan orogeny. The zircon grains of all considered samples preserve a Proterozoic memory suggestive of detrital, metamorphic and igneous origin. The available data fit a frame involving: (1) Neoproterozoic detrital input from cratonic areas of Gondwana; (2) Pan-African/Cadomian assemblage of blocks derived from East and West African Craton; (3) metamorphism and bimodal magmatism between 535 and 579 Ma, within an active margin setting; (4) rifting and opening of Ordovician basins fed by detrital input from the assembled Cadomian blocks. The Paleozoic basins evolved through sedimentation, metamorphism and magmatism during the Variscan orogeny involving Palaeozoic and pre-Paleozoic blocks. The Proterozoic zircon records decidedly decrease in the high grade metamorphic rocks affected by Variscan pervasive partial melting.

  17. The age of the Tunas formation in the Sauce Grande basin-Ventana foldbelt (Argentina): Implications for the Permian evolution of the southwestern margin of Gondwana (United States)

    López-Gamundí, Oscar; Fildani, Andrea; Weislogel, Amy; Rossello, Eduardo


    New SHRIMP radiogenic isotope dating on zircons in tuffs (280.8 ± 1.9 Ma) confirms the Early Permian (Artinskian) age of the uppermost section of the Tunas Formation. Tuff-rich levels in the Tunas Formation are exposed in the Ventana foldbelt of central Argentina; they are part of a deltaic to fluvial section corresponding to the late overfilled stage of the Late Paleozoic Sauce Grande foreland basin. Recent SHRIMP dating of zircons from the basal Choiyoi volcanics exposed in western Argentina yielded an age of 281.4 ± 2.5 Ma (Rocha-Campos et al., 2011). The new data for the Tunas tuffs suggest that the volcanism present in the Sauce Grande basin can be considered as the distal equivalent of the earliest episodes of the Choiyoi volcanism of western Argentina. From the palaeoclimatic viewpoint the new Tunas SHRIMP age confirms that by early Artinskian glacial conditions ceased in the Sauce Grande basin and, probably, in adajacent basins in western Gondwana.

  18. Phanerozoic tectonic evolution of the Circum-North Pacific (United States)

    Nokleberg, Warren J.; Parfenov, Leonid M.; Monger, James W.H.; Norton, Ian O.; Khanchuk, Alexander I.; Stone, David B.; Scotese, Christopher R.; Scholl, David W.; Fujita, Kazuya


    the ancestral margins of present-day Northeast Asia and northwestern North America. The rifting resulted in the fragmentation of each continent and the formation of cratonal and passive continental-margin terranes that eventually migrated and accreted to other sites along the evolving margins of the original or adjacent continents. (2) From about the Late Triassic through the mid-Cretaceous, a succession of island arcs and tectonically paired subduction zones formed near the continental margins. (3) From about mainly the mid-Cretaceous through the present, a succession of igneous arcs and tectonically paired subduction zones formed along the continental margins. (4) From about the Jurassic to the present, oblique convergence and rotations caused orogenparallel sinistral and then dextral displacements within the upper-plate margins of cratons that have become Northeast Asia and North America. The oblique convergences and rotations resulted in the fragmentation, displacement, and duplication of formerly more nearly continuous arcs, subduction zones, and passive continental margins. These fragments were subsequently accreted along the expanding continental margins. (5) From the Early Jurassic through Tertiary, movement of the upper continental plates toward subduction zones resulted in strong plate coupling and accretion of the former island arcs and subduction zones to the continental margins. Accretions were accompanied and followed by crustal thickening, anatexis, metamorphism, and uplift. The accretions resulted in substantial growth of the North Asian and North American Continents. (6) During the middle and late Cenozoic, oblique to orthogonal convergence of the Pacifi c plate with present-day Alaska and Northeast Asia resulted in formation of the modern-day ring of volcanoes around the Circum-North Pacific. Oblique convergence between the Pacific plate and Alaska also resulted in major dextral-slip faulting in interior and southern Alaska and along the western p

  19. Estimation of hominoid ancestral population sizes under bayesian coalescent models incorporating mutation rate variation and sequencing errors. (United States)

    Burgess, Ralph; Yang, Ziheng


    Estimation of population parameters for the common ancestors of humans and the great apes is important in understanding our evolutionary history. In particular, inference of population size for the human-chimpanzee common ancestor may shed light on the process by which the 2 species separated and on whether the human population experienced a severe size reduction in its early evolutionary history. In this study, the Bayesian method of ancestral inference of Rannala and Yang (2003. Bayes estimation of species divergence times and ancestral population sizes using DNA sequences from multiple loci. Genetics. 164:1645-1656) was extended to accommodate variable mutation rates among loci and random species-specific sequencing errors. The model was applied to analyze a genome-wide data set of approximately 15,000 neutral loci (7.4 Mb) aligned for human, chimpanzee, gorilla, orangutan, and macaque. We obtained robust and precise estimates for effective population sizes along the hominoid lineage extending back approximately 30 Myr to the cercopithecoid divergence. The results showed that ancestral populations were 5-10 times larger than modern humans along the entire hominoid lineage. The estimates were robust to the priors used and to model assumptions about recombination. The unusually low X chromosome divergence between human and chimpanzee could not be explained by variation in the male mutation bias or by current models of hybridization and introgression. Instead, our parameter estimates were consistent with a simple instantaneous process for human-chimpanzee speciation but showed a major reduction in X chromosome effective population size peculiar to the human-chimpanzee common ancestor, possibly due to selective sweeps on the X prior to separation of the 2 species.

  20. Extensive Chromosomal Reorganization in the Evolution of New World Muroid Rodents (Cricetidae, Sigmodontinae): Searching for Ancestral Phylogenetic Traits (United States)

    Pereira, Adenilson Leão; Malcher, Stella Miranda; Nagamachi, Cleusa Yoshiko; O’Brien, Patricia Caroline Mary; Ferguson-Smith, Malcolm Andrew; Mendes-Oliveira, Ana Cristina; Pieczarka, Julio Cesar


    Sigmodontinae rodents show great diversity and complexity in morphology and ecology. This diversity is accompanied by extensive chromosome variation challenging attempts to reconstruct their ancestral genome. The species Hylaeamys megacephalus–HME (Oryzomyini, 2n = 54), Necromys lasiurus—NLA (Akodontini, 2n = 34) and Akodon sp.–ASP (Akodontini, 2n = 10) have extreme diploid numbers that make it difficult to understand the rearrangements that are responsible for such differences. In this study we analyzed these changes using whole chromosome probes of HME in cross-species painting of NLA and ASP to construct chromosome homology maps that reveal the rearrangements between species. We include data from the literature for other Sigmodontinae previously studied with probes from HME and Mus musculus (MMU) probes. We also use the HME probes on MMU chromosomes for the comparative analysis of NLA with other species already mapped by MMU probes. Our results show that NLA and ASP have highly rearranged karyotypes when compared to HME. Eleven HME syntenic blocks are shared among the species studied here. Four syntenies may be ancestral to Akodontini (HME2/18, 3/25, 18/25 and 4/11/16) and eight to Sigmodontinae (HME26, 1/12, 6/21, 7/9, 5/17, 11/16, 20/13 and 19/14/19). Using MMU data we identified six associations shared among rodents from seven subfamilies, where MMU3/18 and MMU8/13 are phylogenetic signatures of Sigmodontinae. We suggest that the associations MMU2entire, MMU6proximal/12entire, MMU3/18, MMU8/13, MMU1/17, MMU10/17, MMU12/17, MMU5/16, MMU5/6 and MMU7/19 are part of the ancestral Sigmodontinae genome. PMID:26800516

  1. Human Genetic Ancestral Composition Correlates with the Origin of Mycobacterium leprae Strains in a Leprosy Endemic Population (United States)

    Cardona-Castro, Nora; Cortés, Edwin; Beltrán, Camilo; Romero, Marcela; Badel-Mogollón, Jaime E.; Bedoya, Gabriel


    Recent reports have suggested that leprosy originated in Africa, extended to Asia and Europe, and arrived in the Americas during European colonization and the African slave trade. Due to colonization, the contemporary Colombian population is an admixture of Native-American, European and African ancestries. Because microorganisms are known to accompany humans during migrations, patterns of human migration can be traced by examining genomic changes in associated microbes. The current study analyzed 118 leprosy cases and 116 unrelated controls from two Colombian regions endemic for leprosy (Atlantic and Andean) in order to determine possible associations of leprosy with patient ancestral background (determined using 36 ancestry informative markers), Mycobacterium leprae genotype and/or patient geographical origin. We found significant differences between ancestral genetic composition. European components were predominant in Andean populations. In contrast, African components were higher in the Atlantic region. M. leprae genotypes were then analyzed for cluster associations and compared with the ancestral composition of leprosy patients. Two M. leprae principal clusters were found: haplotypes C54 and T45. Haplotype C54 associated with African origin and was more frequent in patients from the Atlantic region with a high African component. In contrast, haplotype T45 associated with European origin and was more frequent in Andean patients with a higher European component. These results suggest that the human and M. leprae genomes have co-existed since the African and European origins of the disease, with leprosy ultimately arriving in Colombia during colonization. Distinct M. leprae strains followed European and African settlement in the country and can be detected in contemporary Colombian populations. PMID:26360617

  2. The ear region of earliest known elephant relatives: new light on the ancestral morphotype of proboscideans and afrotherians. (United States)

    Schmitt, Arnaud; Gheerbrant, Emmanuel


    One of the last major clades of placental mammals recognized was the Afrotheria, which comprises all main endemic African mammals. This group includes the ungulate-like paenungulates, and among them the elephant order Proboscidea. Among afrotherians, the petrosal anatomy remains especially poorly known in Proboscidea. We provide here the first comparative CT scan study of the ear region of the two earliest known proboscideans (and paenungulates), Eritherium and Phosphatherium, from the mid Palaeocene and early Eocene of Morocco. It is helpful to characterize the ancestral morphotype of Proboscidea to understand petrosal evolution within proboscideans and afrotherians. The petrosal structure of these two taxa shows several differences. Eritherium is more primitive than Phosphatherium and closer to the basal paenungulate Ocepeia in several traits (inflated tegmen tympani, very deep fossa subarcuata and ossified canal for ramus superior of stapedial artery). Phosphatherium, however, retains plesiomorphies such as a true crus commune secundaria. A cladistic analysis of petrosal traits of Eritherium and Phosphatherium among Proboscidea results in a single tree with a low level of homoplasy in which Eritherium, Phosphatherium and Numidotherium are basal. This contrasts with previous phylogenetic studies showing homoplasy in petrosal evolution among Tethytheria. It suggests that evolutionary modalities of petrosal characters differ with the taxonomic level among Afrotheria: noticeable convergences occurred among the paenungulate orders, whereas little homoplasy seems to have occurred at intra-ordinal level in orders such as Proboscidea. Most petrosal features of both Eritherium and Phosphatherium are primitive. The ancestral petrosal morphotype of Proboscidea was not specialized but was close to the generalized condition of paenungulates, afrotherians, and even eutherians. This is consistent with cranial and dental characters of Eritherium, suggesting that the ancestral

  3. Saccharomyces cerevisiae Bat1 and Bat2 aminotransferases have functionally diverged from the ancestral-like Kluyveromyces lactis orthologous enzyme.

    Directory of Open Access Journals (Sweden)

    Maritrini Colón

    Full Text Available BACKGROUND: Gene duplication is a key evolutionary mechanism providing material for the generation of genes with new or modified functions. The fate of duplicated gene copies has been amply discussed and several models have been put forward to account for duplicate conservation. The specialization model considers that duplication of a bifunctional ancestral gene could result in the preservation of both copies through subfunctionalization, resulting in the distribution of the two ancestral functions between the gene duplicates. Here we investigate whether the presumed bifunctional character displayed by the single branched chain amino acid aminotransferase present in K. lactis has been distributed in the two paralogous genes present in S. cerevisiae, and whether this conservation has impacted S. cerevisiae metabolism. PRINCIPAL FINDINGS: Our results show that the KlBat1 orthologous BCAT is a bifunctional enzyme, which participates in the biosynthesis and catabolism of branched chain aminoacids (BCAAs. This dual role has been distributed in S. cerevisiae Bat1 and Bat2 paralogous proteins, supporting the specialization model posed to explain the evolution of gene duplications. BAT1 is highly expressed under biosynthetic conditions, while BAT2 expression is highest under catabolic conditions. Bat1 and Bat2 differential relocalization has favored their physiological function, since biosynthetic precursors are generated in the mitochondria (Bat1, while catabolic substrates are accumulated in the cytosol (Bat2. Under respiratory conditions, in the presence of ammonium and BCAAs the bat1Δ bat2Δ double mutant shows impaired growth, indicating that Bat1 and Bat2 could play redundant roles. In K. lactis wild type growth is independent of BCAA degradation, since a Klbat1Δ mutant grows under this condition. CONCLUSIONS: Our study shows that BAT1 and BAT2 differential expression and subcellular relocalization has resulted in the distribution of the

  4. Human Genetic Ancestral Composition Correlates with the Origin of Mycobacterium leprae Strains in a Leprosy Endemic Population. (United States)

    Cardona-Castro, Nora; Cortés, Edwin; Beltrán, Camilo; Romero, Marcela; Badel-Mogollón, Jaime E; Bedoya, Gabriel


    Recent reports have suggested that leprosy originated in Africa, extended to Asia and Europe, and arrived in the Americas during European colonization and the African slave trade. Due to colonization, the contemporary Colombian population is an admixture of Native-American, European and African ancestries. Because microorganisms are known to accompany humans during migrations, patterns of human migration can be traced by examining genomic changes in associated microbes. The current study analyzed 118 leprosy cases and 116 unrelated controls from two Colombian regions endemic for leprosy (Atlantic and Andean) in order to determine possible associations of leprosy with patient ancestral background (determined using 36 ancestry informative markers), Mycobacterium leprae genotype and/or patient geographical origin. We found significant differences between ancestral genetic composition. European components were predominant in Andean populations. In contrast, African components were higher in the Atlantic region. M. leprae genotypes were then analyzed for cluster associations and compared with the ancestral composition of leprosy patients. Two M. leprae principal clusters were found: haplotypes C54 and T45. Haplotype C54 associated with African origin and was more frequent in patients from the Atlantic region with a high African component. In contrast, haplotype T45 associated with European origin and was more frequent in Andean patients with a higher European component. These results suggest that the human and M. leprae genomes have co-existed since the African and European origins of the disease, with leprosy ultimately arriving in Colombia during colonization. Distinct M. leprae strains followed European and African settlement in the country and can be detected in contemporary Colombian populations.

  5. Estimating Divergence Time and Ancestral Effective Population Size of Bornean and Sumatran Orangutan Subspecies Using a Coalescent Hidden Markov Model

    DEFF Research Database (Denmark)

    Mailund, Thomas; Dutheil, Julien; Hobolth, Asger


    event has occurred to split them apart. The size of these segments of constant divergence depends on the recombination rate, but also on the speciation time, the effective population size of the ancestral population, as well as demographic effects and selection. Thus, inference of these parameters may......ue to genetic variation in the ancestor of two populations or two species, the divergence time for DNA sequences from two populations is variable along the genome. Within genomic segments all bases will share the same divergence—because they share a most recent common ancestor—when no recombination...

  6. North Pacific Pelagic Seabird Database (NPPSD) (United States)

    U.S. Geological Survey, Department of the Interior — The North Pacific Pelagic Seabird Database (NPPSD) was created in 2005 to consolidate data on the oceanic distribution of marine bird species in the North Pacific....

  7. Pacific Northwest Salmon Habitat Project Database (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In the Pacific Northwest Salmon Habitat Project Database Across the Pacific Northwest, both public and private agents are working to improve riverine habitat for a...

  8. 76 FR 33641 - Safety Zone; The Pacific Grove Feast of Lanterns, Fireworks Display, Pacific Grove, CA (United States)


    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; The Pacific Grove Feast of Lanterns... Lovers Point, in Pacific Grove, California in support of the Pacific Grove Feast of Lanterns Fireworks... regulations must be in effect during the event. Basis and Purpose Pacific Grove Feast of Lanterns will...

  9. 78 FR 33240 - International Fisheries; Pacific Tuna Fisheries; Fishing Restrictions in the Eastern Pacific Ocean (United States)


    ..., Canada, China, Chinese Taipei (Taiwan), Colombia, Costa Rica, Ecuador, El Salvador, the European Union...; Pacific Tuna Fisheries; Fishing Restrictions in the Eastern Pacific Ocean AGENCY: National Marine... commercial retention of Pacific bluefin tuna by U.S. fishing vessels operating in the Eastern Pacific...

  10. Asian Pacific Journal of Tropical Biomedicine

    Institute of Scientific and Technical Information of China (English)


    APJTB MonthlyAims&Scope Asian Pacific Journal of Tropical Biomedicine(APJTB)is administrated by Hainan Medical University and sponsored by Asian Pacific Tropical Medicine Press,and aims to establish an international academic communicating platform for researchers of tropical biomedicine and public health workers,especially specialists and scholars of the Asian Pacific region and worldwide on tropical biomedicine research,to

  11. Reconstruction of ancestral chromosome architecture and gene repertoire reveals principles of genome evolution in a model yeast genus. (United States)

    Vakirlis, Nikolaos; Sarilar, Véronique; Drillon, Guénola; Fleiss, Aubin; Agier, Nicolas; Meyniel, Jean-Philippe; Blanpain, Lou; Carbone, Alessandra; Devillers, Hugo; Dubois, Kenny; Gillet-Markowska, Alexandre; Graziani, Stéphane; Huu-Vang, Nguyen; Poirel, Marion; Reisser, Cyrielle; Schott, Jonathan; Schacherer, Joseph; Lafontaine, Ingrid; Llorente, Bertrand; Neuvéglise, Cécile; Fischer, Gilles


    Reconstructing genome history is complex but necessary to reveal quantitative principles governing genome evolution. Such reconstruction requires recapitulating into a single evolutionary framework the evolution of genome architecture and gene repertoire. Here, we reconstructed the genome history of the genus Lachancea that appeared to cover a continuous evolutionary range from closely related to more diverged yeast species. Our approach integrated the generation of a high-quality genome data set; the development of AnChro, a new algorithm for reconstructing ancestral genome architecture; and a comprehensive analysis of gene repertoire evolution. We found that the ancestral genome of the genus Lachancea contained eight chromosomes and about 5173 protein-coding genes. Moreover, we characterized 24 horizontal gene transfers and 159 putative gene creation events that punctuated species diversification. We retraced all chromosomal rearrangements, including gene losses, gene duplications, chromosomal inversions and translocations at single gene resolution. Gene duplications outnumbered losses and balanced rearrangements with 1503, 929, and 423 events, respectively. Gene content variations between extant species are mainly driven by differential gene losses, while gene duplications remained globally constant in all lineages. Remarkably, we discovered that balanced chromosomal rearrangements could be responsible for up to 14% of all gene losses by disrupting genes at their breakpoints. Finally, we found that nonsynonymous substitutions reached fixation at a coordinated pace with chromosomal inversions, translocations, and duplications, but not deletions. Overall, we provide a granular view of genome evolution within an entire eukaryotic genus, linking gene content, chromosome rearrangements, and protein divergence into a single evolutionary framework.

  12. Topologies of the conditional ancestral trees and full-likelihood-based inference in the general coalescent tree framework. (United States)

    Sargsyan, Ori


    The general coalescent tree framework is a family of models for determining ancestries among random samples of DNA sequences at a nonrecombining locus. The ancestral models included in this framework can be derived under various evolutionary scenarios. Here, a computationally tractable full-likelihood-based inference method for neutral polymorphisms is presented, using the general coalescent tree framework and the infinite-sites model for mutations in DNA sequences. First, an exact sampling scheme is developed to determine the topologies of conditional ancestral trees. However, this scheme has some computational limitations and to overcome these limitations a second scheme based on importance sampling is provided. Next, these schemes are combined with Monte Carlo integrations to estimate the likelihood of full polymorphism data, the ages of mutations in the sample, and the time of the most recent common ancestor. In addition, this article shows how to apply this method for estimating the likelihood of neutral polymorphism data in a sample of DNA sequences completely linked to a mutant allele of interest. This method is illustrated using the data in a sample of DNA sequences at the APOE gene locus.

  13. Conservation of shh cis-regulatory architecture of the coelacanth is consistent with its ancestral phylogenetic position

    Directory of Open Access Journals (Sweden)

    Lang Michael


    Full Text Available Abstract Background The modern coelacanth (Latimeria is the extant taxon of a basal sarcopterygian lineage and sister group to tetrapods. Apart from certain apomorphic traits, its morphology is characterized by a high degree of retention of ancestral vertebrate structures and little morphological change. An insight into the molecular evolution that may explain the unchanged character of Latimeria morphology requires the analysis of the expression patterns of developmental regulator genes and their cis-regulatory modules (CRMs. Results We describe the comparative and functional analysis of the sonic hedgehog (shh genomic region of Latimeria menadoensis. Several putative enhancers in the Latimeria shh locus have been identified by comparisons to sarcopterygian and actinopterygian extant species. Specific sequence conservation with all known actinopterygian enhancer elements has been detected. However, these elements are selectively missing in more recently diverged actinopterygian and sarcopterygian species. The functionality of the putative Latimeria enhancers was confirmed by reporter gene expression analysis in transient transgenic zebrafish and chick embryos. Conclusions Latimeria shh CRMs represent the ancestral set of enhancers that have emerged before the split of lobe-finned and ray-finned fishes. In contrast to lineage-specific losses and differentiations in more derived lineages, Latimeria shh enhancers reveal low levels of sequence diversification. High overall sequence conservation of shh conserved noncoding elements (CNE is consistent with the general trend of high levels of conservation of noncoding DNA in the slowly evolving Latimeria genome.

  14. Mutational Studies on Resurrected Ancestral Proteins Reveal Conservation of Site-Specific Amino Acid Preferences throughout Evolutionary History (United States)

    Risso, Valeria A.; Manssour-Triedo, Fadia; Delgado-Delgado, Asunción; Arco, Rocio; Barroso-delJesus, Alicia; Ingles-Prieto, Alvaro; Godoy-Ruiz, Raquel; Gavira, Jose A.; Gaucher, Eric A.; Ibarra-Molero, Beatriz; Sanchez-Ruiz, Jose M.


    Local protein interactions (“molecular context” effects) dictate amino acid replacements and can be described in terms of site-specific, energetic preferences for any different amino acid. It has been recently debated whether these preferences remain approximately constant during evolution or whether, due to coevolution of sites, they change strongly. Such research highlights an unresolved and fundamental issue with far-reaching implications for phylogenetic analysis and molecular evolution modeling. Here, we take advantage of the recent availability of phenotypically supported laboratory resurrections of Precambrian thioredoxins and β-lactamases to experimentally address the change of site-specific amino acid preferences over long geological timescales. Extensive mutational analyses support the notion that evolutionary adjustment to a new amino acid may occur, but to a large extent this is insufficient to erase the primitive preference for amino acid replacements. Generally, site-specific amino acid preferences appear to remain conserved throughout evolutionary history despite local sequence divergence. We show such preference conservation to be readily understandable in molecular terms and we provide crystallographic evidence for an intriguing structural-switch mechanism: Energetic preference for an ancestral amino acid in a modern protein can be linked to reorganization upon mutation to the ancestral local structure around the mutated site. Finally, we point out that site-specific preference conservation naturally leads to one plausible evolutionary explanation for the existence of intragenic global suppressor mutations. PMID:25392342

  15. New insights from U Pb zircon dating of Early Ordovician magmatism on the northern Gondwana margin: The Urra Formation (SW Iberian Massif, Portugal) (United States)

    Solá, A. R.; Pereira, M. F.; Williams, I. S.; Ribeiro, M. L.; Neiva, A. M. R.; Montero, P.; Bea, F.; Zinger, T.


    The Central Iberian-Ossa-Morena transition zone (SW Iberian Massif) represents a segment of the northern Gondwana margin with a long geodynamic evolution, characterized by the superposition of Cadomian and Variscan events. The Early Ordovician is mainly represented by porphyritic felsic volcaniclastic rocks (the Urra Formation) that pass up into a siliciclastic sediments typical of the Central Iberian Zone (Lower Ordovician Armorican Quartzite Formation). The Urra Formation unconformably overlies the previously deformed and metamorphosed Ediacaran sediments of the Série Negra (with Ossa-Morena Zone paleogeographic affinity). New SHRIMP zircon data obtained from the Urra Formation volcaniclastic rocks indicate an Early Ordovician age ( 206Pb/ 238U ages ranging from 494.6 ± 6.8 Ma to 488.3 ± 5.2 Ma) for this magmatic event. The inherited zircon cores indicate the presence of multicycle protoliths with different Precambrian ages: Neoproterozoic (698-577 Ma), Paleoproterozoic (2.33 Ga) and Paleoarchean (3.2-3.3 Ga). There is a noticeable lack of Meso- to Neoarchean and Mesoproterozoic ages. The data support the hypothesis that the volcaniclastic rocks were derived by partial melting of Cadomian basement (linked to a West African Craton provenance). The Urra Formation volcaniclastic rocks have rhyolitic to dacitic compositions, are peraluminous and similar to calc-alkaline high-K series suites elsewhere. Isotopic signatures present a wide range of values ( 87Sr/ 86Sr) t = 0.7085-0.7190, more restricted ɛNd t (- 2.65 to - 0.35) and δ18O = 9.63-10.34‰, compatible with magmas derived from crustal rocks, including portions of the lower crust. Some samples show disturbance of the Rb-Sr system as shown by unrealistic values for ( 87Sr/ 86Sr) t < 0.703, probably due to Variscan deformation and metamorphism. The volcaniclastic rocks with a significant sedimentary contribution (upper unit) are distinguished from the others by the lowest values of ɛNd t (- 5.53 to - 4

  16. Origin of pegmatites and fluids at Ponta Negra (RJ, Brazil) during late- to post-collisional stages of the Gondwana Assembly (United States)

    Bongiolo, Everton Marques; Renac, Christophe; Piza, Patricia d'Almeida de Toledo; Schmitt, Renata da Silva; Mexias, André Sampaio


    the pegmatites. A linear trend of decreasing CO2 content and δ13CCO2 is consistent with mixtures between (i) carbon derived from organic matter or volatilization of skarns and (ii) inorganic carbon (carbonate). Based on the data obtained, we propose that the pegmatites of Ponta Negra are close to an LCT-type geochemical signature (highly peraluminous magmas with normative corundum), and originated by partial melting of the metasedimentary Palmital succession at depth, during the waning stages of the Búzios Orogeny. The primary melts of the PNP cross-cut both the Neoproterozoic supracrustals and the Paleoproterozoic orthogneissic basement during its ascent and emplacement at higher crustal levels. Variable melt sources explain the slight differences in geochemical compositions among the studied rocks within the metasedimentary succession, which probably include Mn-bearing exhalites, as well as differentiation processes. The 454 ± 5 Ma U-Pb (zircon) age of the Cajú syenogranite overlaps previous geochronological data of 440 ± 11 Ma obtained on a pegmatite dyke at Ponta Negra, bracketing and extending the time interval for the Gondwana assembly collapse magmatism in the region. The heat that triggered this magmatic event could still be a consequence of the collisional orogeny, increasing contents of heat-producing elements, or, a large intraplate extension that followed the Gondwana amalgamation and initiated the formation of Paleozoic basins.

  17. Code breaking in the pacific

    CERN Document Server

    Donovan, Peter


    Covers the historical context and the evolution of the technically complex Allied Signals Intelligence (Sigint) activity against Japan from 1920 to 1945 Describes, explains and analyzes the code breaking techniques developed during the war in the Pacific Exposes the blunders (in code construction and use) made by the Japanese Navy that led to significant US Naval victories

  18. Distribution of Pacific Phanerogam genera

    NARCIS (Netherlands)



    The following is a tabulated list of all Pacific Phanerogam genera. A similar list was published as an appendix to my “Plant geography of the Pacific” (1971). The latter has, in the meantime, become obsolete by new records and changed taxonomic concepts. The new list is here presented in a more cond

  19. New U-Pb ages in the Diablillos Intrusive Complex, Southern Puna, Argentina: A long magmatic event in the Paleozoic Arc, SW Gondwana

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz, Agustin; Hauser, Natalia [Universidade de Brasilia (UnB), DF (Brazil). Instituto de Geociencias. Lab. de Geocronologia; Becchio, Raul; Nieves, Alexis; Suzano, Nestor [Universidad Nacional de Salta (UNSa)-CONICET, Salta (Argentina)


    The Puna geological region comprises Salta, Jujuy and Catamarca provinces, northwestern Argentina. This 4000 meter above sea level high-plateau region lies between the Central Argentinian Andes. The Puna basement in the central Andes consists of Proterozoic–Paleozoic metamorphic rocks and granitoids. Diverse authors, proposed different models to explain the origin of the basement, where two orogenic events are recognized: the Pampean (Upper Precambrian–Lower Cambrian) and Famatinian (Upper Cambrian–Lower Silurian) (e.g. Ramos et al., 1986; Ramos, 1988; Loewy et al., 2004; for opposite points of view see Becchio et al., 1999; Bock et al., 2000; Buttner et al., 2005). Hence, Lucassen et al. (2000) proposed for the Central Andean basement, an evolution in a mobile belt, where the Pampean and Famatinian cycles are not distinct events but, they are one single, non-differentiable event from 600 to 400 Ma. The mobile belt culminated in low-P/ high-T metamorphism at approximately 525-500 Ma. Then, these were followed by a long-lasting high-thermal gradient regime in the mid-crust until Silurian times. Becchio et al., (2011) defined the Diablillos Intrusive Complex (CID, by its Spanish name), emplaced in the Inca Viejo Range. This range splits the Salares Ratones-Centenario with the Salar Diablillos (Fig.1). This Complex is located in the Eastern Magmatic Belt, Southern Puna, Argentina. Here we present new zircons U-Pb ages by LA-MC-ICPMS in the Diablillos Intrusive Complex, contributing to understanding the magmatic event in the lower Paleozoic arc, SW Gondwana. (author)

  20. Moa's Ark or volant ghosts of Gondwana? Insights from nineteen years of ancient DNA research on the extinct moa (Aves: Dinornithiformes) of New Zealand. (United States)

    Allentoft, Morten E; Rawlence, Nicolas J


    The moa (Aves: Dinornithiformes) of New Zealand represent one of the extinct iconic taxa that define the field of ancient DNA (aDNA), and after almost two decades of genetic scrutiny of bones, feathers, coprolites, mummified tissue, eggshell, and sediments, our knowledge of these prehistoric giants has increased significantly. Thanks to molecular and morphological-based research, the insights that have been obtained into moa phylogenetics, phylogeography, and palaeobiology exceeds that of any other extinct taxon. This review documents the strengths of applying a multidisciplinary approach when studying extinct taxa but also shows that cross-disciplinary controversies still remain at the most fundamental levels, with highly conflicting interpretations derived from aDNA and morphology. Moa species diversity, for example, is still heavily debated, as well as their relationship with other ratites and the mode of radiation. In addition to increasing our knowledge on a lineage of extinct birds, further insights into these aspects can clarify some of the basal splits in avian evolution, and the evolutionary implications of the breakup of the prehistoric supercontinent Gondwana. Did a flightless moa ancestor drift away on proto New Zealand (Moa's Ark) or did a volant ancestor arrive by flight? Here we provide an overview of 19 years of aDNA research on moa, critically assess the attempts and controversies in placing the moa lineage among palaeognath birds, and discuss the factors that facilitated the extensive radiation of moa. Finally, we identify the most obvious gaps in the current knowledge to address the future potential research areas in moa genetics.

  1. The jurassic events in the Greater Caucasus basin (Northern Neotethys and the Neuquén basin (West Gondwana: a comparison

    Directory of Open Access Journals (Sweden)

    Dmitry A. Ruban


    Full Text Available Quite a few common tectonic, palaeoenvironmental, and palaeobiological events have been recognized in the Jurassic evolution of the Greater Caucasus basin (Northern Neotethys and the Neuquén basin (West Gondwana. Both basins were originated by the same planetary-scale tectonic force, i.e., by the activity of the Intrapangaean Shear Zone stretching eastwards along the Eurasian margin as the Northern Tethyan Shear Zone. An oxygen depletion occurred in both studied regions in the Toarcian as a result of global anoxia, which provoked a mass extinction. In both basins, the Callovian was a time for the carbonate platform growth, although in the Greater Caucasus, a carbonate platform appeared only in the Late Callovian. A salinity crisis occurred in the Greater Caucasus during the Kimmeridgian-Tithonian, whereas the same took place twice in the Neuquén basin - in the Middle Callovian and in the late Oxfordian-Kimmeridgian. These events were related to the global epoch of evaporite deposition. Some important differences between the considered basins are also documented. Palaeontological data from the Neuquén basin suggest against the mass extinction at the Jurassic-Cretaceous transition. In contrast, data from the Greater Caucasus basin permit to recognize this global event, although its regional peak occurred in the Berriasian. The Jurassic transgressions and regressions in the Greater Caucasus and western Argentina differed, facts that may be explained by the differences in the regional geodynamics. The only common pattern was a stepwise transgression during the Sinemurian-Pliensbachian.

  2. Proto-Pacific-margin source for the Ordovician turbidite submarine fan, Lachlan Orogen, southeast Australia: Geochemical constraints (United States)

    Offler, R.; Fergusson, C. L.


    The Early Palaeozoic proto-Pacific Pacific margin of Gondwana was characterised by a huge turbidite submarine fan with abundant clastic detritus derived from unknown sources within Gondwana. These deposits are widespread in the Lachlan Orogen of southeast Australia and include the Ordovician Adaminaby Group. Here we show that the mudstones and sandstones of the Adaminaby Group have chemical compositions that indicate the detritus in them was derived from a felsic, continental source similar in composition to Post Archean Australian Shales (PAAS). Chondrite normalised REE patterns showing LREE enrichment, flat PAAS normalised patterns and elemental ratios La/Sc, Cr/Th, Cr/V, Th/Sc and Th/U, have been used to support this interpretation. The dominance of quartz, and to a lesser degree plagioclase and biotite in the sandstones, suggests that the source was mainly granodioritic to tonalitic in composition. Th/Yb and Ta/Yb ratios indicate that the source was probably calc-alkaline, continental and shoshonitic. In addition, the presence of detrital muscovite, low-grade metamorphic and felsic volcanic clasts, demonstrates that a low-grade metamorphic terrane and volcanic arc contributed to the detritus observed in the samples. The presence of well-rounded zircons and tourmalines, very high Zr contents, high Zr/Sc and higher Cr/V ratios in some samples particularly in the Shoalhaven River area, indicate that some of the detritus was recycled. SiO2 versus (Al2O3 + K2O + Na2O) plots suggest the source areas experienced conditions varying from humid/semi-humid to semi-arid. Textural features and weathering trends of samples from all locations follow a curved pathway on Al2O3 - (CaO* + Na2O) - K2O (ACNK) diagrams, and indicate that the clays formed from weathering had been K-metasomatised prior to penetrative deformation. Chemical indices of alteration (CIA) reveal that even the freshest sandstones are altered and others are moderately to strongly altered. Discrimination

  3. On Cultural Perspective of Ancestral Hall Couplets in Sanming%三明宗祠楹联的文化透视

    Institute of Scientific and Technical Information of China (English)



    宗祠楹联是宋元以后宗族社会特有的一种艺术形式,是祠堂文化的典型产物。三明宗祠楹联文化蕴涵丰富。有的反映祠堂的祭祀功能;有的追祖溯源,崇仰故土祖根;有的表彰先贤,表达对先人的顶礼膜拜;有的则训勉后人,激励家族不断进取。它们在一定程度上记录着各家族的繁衍生息、荣衰变迁,为我们探知三明祠堂文化、了解三明宗族发展的历史以及研究三明历史文化名人等提供了珍贵的资料;同时,它们又以宗经明道、敦品立德为要旨,对促进社会和谐有序与可持续发展也具有重要意义,值得重视。%The ancestral hall couplet is a unique art form in clan society of the Song and Yuan dynasties,which is a typical product of the ancestral temple culture.The ancestral hall couplets in Sanming have rich cultural implications,such as reflecting the ritual function of the ancestral hall,recovering ancestral source,enshrining the homeland ancestral root,the recognition of the sages,the expression of pay homage to the ancestors,encouraging future generations and inspiring family to make progress.To a certain extent,they are a record of the development of each family as well as their changes in prosperity and decline,which provide valuable information for probing the ancestral hall culture in Sanming,understanding the history of ancestral hall couplets' development and studying the historical and cultural celebrities in Sanming.What's more,their following traditional ideas and regulating ethical conduct have important significance to promote harmonious society and sustainable development,which deserves attention.

  4. Mating animals by minimising the covariance between ancestral contributions generates less inbreeding without compromising genetic gain in breeding schemes with truncation selection

    DEFF Research Database (Denmark)

    Henryon, M; Berg, P; Sørensen, A C


    We reasoned that mating animals by minimising the covariance between ancestral contributions (MCAC mating) will generate less inbreeding and at least as much genetic gain as minimum-coancestry mating in breeding schemes where the animals are truncation-selected. We tested this hypothesis by stoch......We reasoned that mating animals by minimising the covariance between ancestral contributions (MCAC mating) will generate less inbreeding and at least as much genetic gain as minimum-coancestry mating in breeding schemes where the animals are truncation-selected. We tested this hypothesis...

  5. EREM: Parameter Estimation and Ancestral Reconstruction by Expectation-Maximization Algorithm for a Probabilistic Model of Genomic Binary Characters Evolution

    Directory of Open Access Journals (Sweden)

    Liran Carmel


    Full Text Available Evolutionary binary characters are features of species or genes, indicating the absence (value zero or presence (value one of some property. Examples include eukaryotic gene architecture (the presence or absence of an intron in a particular locus, gene content, and morphological characters. In many studies, the acquisition of such binary characters is assumed to represent a rare evolutionary event, and consequently, their evolution is analyzed using various flavors of parsimony. However, when gain and loss of the character are not rare enough, a probabilistic analysis becomes essential. Here, we present a comprehensive probabilistic model to describe the evolution of binary characters on a bifurcating phylogenetic tree. A fast software tool, EREM, is provided, using maximum likelihood to estimate the parameters of the model and to reconstruct ancestral states (presence and absence in internal nodes and events (gain and loss events along branches.

  6. Ancestral mutations as a tool for solubilizing proteins: The case of a hydrophobic phosphate-binding protein

    Directory of Open Access Journals (Sweden)

    Daniel Gonzalez


    Full Text Available Stable and soluble proteins are ideal candidates for functional and structural studies. Unfortunately, some proteins or enzymes can be difficult to isolate, being sometimes poorly expressed in heterologous systems, insoluble and/or unstable. Numerous methods have been developed to address these issues, from the screening of various expression systems to the modification of the target protein itself. Here we use a hydrophobic, aggregation-prone, phosphate-binding protein (HPBP as a case study. We describe a simple and fast method that selectively uses ancestral mutations to generate a soluble, stable and functional variant of the target protein, here named sHPBP. This variant is highly expressed in Escherichia coli, is easily purified and its structure was solved at much higher resolution than its wild-type progenitor (1.3 versus 1.9 Å, respectively.

  7. The mechanistic basis of hemoglobin adaptation in the high-flying barheaded goose: insights from ancestral protein resurrection

    DEFF Research Database (Denmark)

    Natarajan, Chandrasekhar; Kumar, Amit; Moriyama, Hideaki


    of this text-book example of biochemical adaptation. Previous hypotheses about the molecular basis of the evolved increase in Hb-O2 affinity were tested by engineering BHGspecific mutations into recombinant human Hb. This approach can provide important insights, but one problem with such ‘horizontal......’ comparisons – swapping residues between proteins of contemporary species – is that the focal mutations are introduced into a sequence context that may not be evolutionarily relevant. If mutations have context-dependent effects, then introducing BHG-specific substitutions into human Hb may not recapitulate...... the functional effects of causative mutations on the genetic background in which they actually occurred during evolution (i.e., in the BHG ancestor). An alternative ‘vertical’ approach is to reconstruct and resurrect ancestral proteins to test the effects of historical mutations on the genetic background...

  8. ¿Con o sin ancestros? Vigencia de lo ancestral en la Amazonía peruana

    Directory of Open Access Journals (Sweden)

    Thomas Mouriès


    Full Text Available The existence —or not— of the concept of ancestors in the indigenous Amazon has been the subject of much debate. However, regional leaders do not hesitate to call upon ‘ancestral’ knowledge, customs, or territories in the sense that, from an academic point of view, could appear enigmatic. «Ancestral, but… with or without ancestors?» is the question a confused anthropologist might ask. In this article, I propose to offer elements of a response to this question,based on a case study in Peru. First I analyze how Amazonian indigenous leaders, following international law, have adopted the legal notion of ‘ancestral possession’ of their territory to adapt it to the political sphere. This approach accounts for the recent generalization and uniformization of the term ‘ancestral’, but poses the problem of how it articulates with the indigenous cosmologies that it supposes to reflect. For this reason, I explore in the second section the pertinence of the category of ‘ancestor’ in the indigenous Amazon, briefly drawing upon the academic debate in order to define inwhat way this category takes on meaning. Based on testimony from an experienced Awajún leader, we thus return in the third section more explicitly to the different meanings and planes of reference that unfold when one uses the term ‘ancestral’, showing how Amazonian indigenous people not only adopt external conceptual elements and arguments, but also transform them based on their own cosmological singularities and political perspectives.

  9. PhyloBot: A Web Portal for Automated Phylogenetics, Ancestral Sequence Reconstruction, and Exploration of Mutational Trajectories. (United States)

    Hanson-Smith, Victor; Johnson, Alexander


    The method of phylogenetic ancestral sequence reconstruction is a powerful approach for studying evolutionary relationships among protein sequence, structure, and function. In particular, this approach allows investigators to (1) reconstruct and "resurrect" (that is, synthesize in vivo or in vitro) extinct proteins to study how they differ from modern proteins, (2) identify key amino acid changes that, over evolutionary timescales, have altered the function of the protein, and (3) order historical events in the evolution of protein function. Widespread use of this approach has been slow among molecular biologists, in part because the methods require significant computational expertise. Here we present PhyloBot, a web-based software tool that makes ancestral sequence reconstruction easy. Designed for non-experts, it integrates all the necessary software into a single user interface. Additionally, PhyloBot provides interactive tools to explore evolutionary trajectories between ancestors, enabling the rapid generation of hypotheses that can be tested using genetic or biochemical approaches. Early versions of this software were used in previous studies to discover genetic mechanisms underlying the functions of diverse protein families, including V-ATPase ion pumps, DNA-binding transcription regulators, and serine/threonine protein kinases. PhyloBot runs in a web browser, and is available at the following URL: The software is implemented in Python using the Django web framework, and runs on elastic cloud computing resources from Amazon Web Services. Users can create and submit jobs on our free server (at the URL listed above), or use our open-source code to launch their own PhyloBot server.

  10. The impact of ancestral population size and incomplete lineage sorting on Bayesian estimation of species divergence times

    Institute of Scientific and Technical Information of China (English)

    Konstantinos ANGELIS; Mario DOS REIS


    Although the effects of the coalescent process on sequence divergence and genealogies are well understood, the vir-tual majority of studies that use molecular sequences to estimate times of divergence among species have failed to account for the coalescent process. Here we study the impact of ancestral population size and incomplete lineage sorting on Bayesian estimates of species divergence times under the molecular clock when the inference model ignores the coalescent process. Using a combi-nation of mathematical analysis, computer simulations and analysis of real data, we find that the errors on estimates of times and the molecular rate can be substantial when ancestral populations are large and when there is substantial incomplete lineage sort-ing. For example, in a simple three-species case, we find that if the most precise fossil calibration is placed on the root of the phylogeny, the age of the internal node is overestimated, while if the most precise calibration is placed on the internal node, then the age of the root is underestimated. In both cases, the molecular rate is overestimated. Using simulations on a phylogeny of nine species, we show that substantial errors in time and rate estimates can be obtained even when dating ancient divergence events. We analyse the hominoid phylogeny and show that estimates of the neutral mutation rate obtained while ignoring the coalescent are too high. Using a coalescent-based technique to obtain geological times of divergence, we obtain estimates of the mutation rate that are within experimental estimates and we also obtain substantially older divergence times within the phylogeny [Current Zoology 61 (5): 874–885, 2015].

  11. P-T path and timing of crustal thickening during amalgamation of East and West Gondwana: A case study from the Hafafit Metamorphic Complex, Eastern Desert of Egypt (United States)

    Abu El-Enen, Mahrous M.; Abu-Alam, Tamer S.; Whitehouse, Martin J.; Ali, Kamal A.; Okrusch, Martin


    The southeastern sector of the Hafafit Metamorphic Complex, southern Eastern Desert of Egypt comprises infrastructural orthogneisses of tonalite and syenogranite parentage, amphibolites, and a volcano-sedimentary association. These are overthrust by an obducted suprastructural ophiolite nappes via the Nugrus thrust. The protolith of the biotite-hornblende-gneisses was formed during island-arc accretion, while that of the garnet-biotite gneisses were formed in a within-plate regime, consistent with a transition to a post-collisional setting. The volcano-sedimentary association comprises interbedded and intercalated highly foliated metapelitic schists, metabasites, and leucocratic gneisses, deposited in a back-arc basin. The metapelites and the leucocratic gneisses originated from immature Fe-shales and arkoses derived from intermediate-mafic and acidic igneous rocks, respectively, via weak chemical weathering in a tectonically active island arc terrane. The intercalated amphibolites were derived from tholeiitic basalts generated in a back-arc setting. The volcano-sedimentary association was metamorphosed under upper-amphibolite facies conditions with pressures of 9-13 kbar and temperatures of 570-675 °C, as derived from conventional geothermobarometry and pseudosection calculation. A steep, tight clockwise P-T path is constrained and a geothermal gradient around 20 °C/km is estimated for the peak metamorphism. We assume that deformation and metamorphism are due to crustal thickening during the collision of East and West Gondwana, where peak metamorphism took place in the middle to lower crust at 33 km average crustal depth. This was followed by a subsequent quasi-isothermal decompression due to rapid exhumation during wrench tectonics. Sinistral transcurrent shearing with extensional denudation resulted in vertical ductile thinning that was accompanied by heat input from magmatism, as indicated by a higher geothermal gradient during retrograde metamorphism and

  12. Modelos de cinemática de placas para Antártida durante la ruptura de Gondwana: una revisión

    Directory of Open Access Journals (Sweden)

    M.E. Ghidella


    Full Text Available La historia de apertura del mar de Weddell y del Oc éano Atlántico Sur es crítica para comprender la ruptura de Gondwana y la evolución geológica de Antártida desde el Jurásico temprano. La dispersión de los fragmentos gondwánicos es importante para entender la circulación oceánica del pasado, descifrar la historia de las cuencas sedimentarias ubicadas al Este de la Península Antártica y establecer posibles rutas de dispersión de flora y fauna entre los continentes australes. Desafortunadamente, la tectónica del mar de Weddell es difícil de resolver debido a la escasez de datos y a su inherente complejidad. Aunque se ha alcanzado un progreso muy grande el los últimos 20 años, con nuevos datos aeromagnéticos marinos y mapas de gravedad derivada de altimetría satelital, todavía hay varios modelos en consideración que difieren en edades corticales y esquemas de apertura. En este trabajo se presenta una revisión de cuatro de esos modelos. Utilizando polos de rotación, isócronas sintéticas y líneas de flujo, se ha procedido hacia atrás en el tiempo comenzando en la anomalía magnética 34 (83,5 millones de años, porque la misma está relativamente bien definida en los océanos, y se presentan mapas de edades de corteza que muestran la trayectoria estimada del punto triple Sudamérica - Antártida - África para cada modelo. Asimismo se muestran gráficos de las reconstrucciones en cuatro épocas elegidas para todos los modelos usando la misma proyección y escala para facilitar la comparación. La variedad de suposiciones simplificadoras que debieron hacerse en cada modelo, recurriendo a fragmentación de placas para considerar las numerosas cuencas de syn-rift y períodos de extensión, son fuertes indicadores de que la tectónica de placas rígidas es un modelo demasiado simple para el presente problema.

  13. Pacific Flyway management plan for the Pacific Flyway Population of greater white-fronted geese (United States)

    US Fish and Wildlife Service, Department of the Interior — For the purposes of this management plan, the greater white-fronted goose subspecies (Anseralbifrons frontalis) occurring in the Pacific Flyway is termed the Pacific...

  14. Oceanographic data - Integrated acoustic and trawl survey of Pacific hake off the Pacific Coast (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Integrated acoustic and trawl surveys are used to assess the distribution, biomass, and biology of Pacific hake along the Pacific coasts of the United States and...

  15. Biological data - Integrated acoustic and trawl survey of Pacific hake off the Pacific Coast (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Integrated acoustic and trawl surveys are used to assess the distribution, biomass, and biology of Pacific hake along the Pacific coasts of the United States and...

  16. Pacific Hake - Growth and natal origin of Pacific hake from the Georgia Basin DPS (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Pacific hake (Merluccius productus) is an abundant species residing along the Pacific coast from the Gulf of California to the Strait of Georgia. It is the most...

  17. Climate Prediction Center (CPC) East Pacific/ North Pacific Teleconnection Pattern Index (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Monthly tabulated index of the East Pacific/ North Pacific teleconnection pattern. The data spans the period 1950 to present. The index is derived from a rotated...

  18. Asian Pacific Journal of Tropical Biomedicine

    Institute of Scientific and Technical Information of China (English)


    APJTB Monthly Aims&Scope Asian Pacific Journal of Tropical Biomedicine(APJTB)aims to set up and provide an international academic communication platform for physicians,medical scientists,allied health scientists and public health workers,especially those in the Asian Pacific region and worldwide on tropical biomedicine,infectious diseases and public health,and to meet the growing challenges of understanding,preventing and controlling the dramatic global emergence and reemergence of infectious diseases in the Asian Pacific region.

  19. Complete tribal sampling reveals basal split in Muscidae (Diptera), confirms saprophagy as ancestral feeding mode, and reveals an evolutionary correlation between instar numbers and carnivory

    DEFF Research Database (Denmark)

    Kutty, Sujatha Narayanan; Pont, Adrian C.; Meier, Rudolf;


    of the number of larval instars from three (ancestral) to two and one. The genus Achanthiptera which was previously in its own subfamily is shown to be closely related to Azeliini. However, it appears that Azeliinae is paraphyletic because Muscinae is sister-group to the Azeliini while the azeliine...

  20. Ancestral state reconstructions require biological evidence to test evolutionary hypotheses: A case study examining the evolution of reproductive mode in squamate reptiles. (United States)

    Griffith, Oliver W; Blackburn, Daniel G; Brandley, Matthew C; Van Dyke, James U; Whittington, Camilla M; Thompson, Michael B


    To understand evolutionary transformations it is necessary to identify the character states of extinct ancestors. Ancestral character state reconstruction is inherently difficult because it requires an accurate phylogeny, character state data, and a statistical model of transition rates and is fundamentally constrained by missing data such as extinct taxa. We argue that model based ancestral character state reconstruction should be used to generate hypotheses but should not be considered an analytical endpoint. Using the evolution of viviparity and reversals to oviparity in squamates as a case study, we show how anatomical, physiological, and ecological data can be used to evaluate hypotheses about evolutionary transitions. The evolution of squamate viviparity requires changes to the timing of reproductive events and the successive loss of features responsible for building an eggshell. A reversal to oviparity requires that those lost traits re-evolve. We argue that the re-evolution of oviparity is inherently more difficult than the reverse. We outline how the inviability of intermediate phenotypes might present physiological barriers to reversals from viviparity to oviparity. Finally, we show that ecological data supports an oviparous ancestral state for squamates and multiple transitions to viviparity. In summary, we conclude that the first squamates were oviparous, that frequent transitions to viviparity have occurred, and that reversals to oviparity in viviparous lineages either have not occurred or are exceedingly rare. As this evidence supports conclusions that differ from previous ancestral state reconstructions, our paper highlights the importance of incorporating biological evidence to evaluate model-generated hypotheses.

  1. Tectonic Evolution of the Jurassic Pacific Plate (United States)

    Nakanishi, M.; Ishihara, T.


    We present the tectonic evolution of the Jurassic Pacific plate based on magnetic anomly lineations and abyssal hills. The Pacific plate is the largest oceanic plate on Earth. It was born as a microplate aroud the Izanagi-Farallon-Phoenix triple junction about 192 Ma, Early Jurassic [Nakanishi et al., 1992]. The size of the Pacific plate at 190 Ma was nearly half that of the present Easter or Juan Fernandez microplates in the East Pacific Rise [Martinez et at, 1991; Larson et al., 1992]. The plate boundary surrounding the Pacific plate from Early Jurassic to Early Cretaceous involved the four triple junctions among Pacific, Izanagi, Farallon, and Phoenix plates. The major tectonic events as the formation of oceanic plateaus and microplates during the period occurred in the vicinity of the triple junctions [e.g., Nakanishi and Winterer, 1998; Nakanishi et al., 1999], implying that the study of the triple junctions is indispensable for understanding the tectonic evolution of the Pacific plate. Previous studies indicate instability of the configuration of the triple junctions from Late Jurassic to Early Cretaceous (155-125 Ma). On the other hand, the age of the birth of the Pacific plate was determined assuming that all triple junctions had kept their configurations for about 30 m.y. [Nakanishi et al., 1992] because of insufficient information of the tectonic history of the Pacific plate before Late Jurassic.Increase in the bathymetric and geomagnetic data over the past two decades enables us to reveal the tectonic evolution of the Pacific-Izanagi-Farallon triple junction before Late Jurassic. Our detailed identication of magnetic anomaly lineations exposes magnetic bights before anomaly M25. We found the curved abyssal hills originated near the triple junction, which trend is parallel to magnetic anomaly lineations. These results imply that the configuration of the Pacific-Izanagi-Farallon triple junction had been RRR before Late Jurassic.

  2. The ancestral cascades arc: Cenozoic evolution of the central Sierra Nevada (California) and the birth of the new plate boundary (United States)

    Busby, C.J.; Hagan, J.C.; Putirka, K.; Pluhar, C.J.; Gans, P.B.; Wagner, D.L.; Rood, D.; DeOreo, S.B.; Skilling, I.


    We integrate new stratigraphic, structural, geochemical, geochronological, and magnetostratigraphic data on Cenozoic volcanic rocks in the central Sierra Nevada to arrive at closely inter-related new models for: (1) the paleogeography of the ancestral Cascades arc, (2) the stratigraphic record of uplift events in the Sierra Nevada, (3) the tectonic controls on volcanic styles and compositions in the arc, and (4) the birth of a new plate margin. Previous workers have assumed that the ancestral Cascades arc consisted of stratovolcanoes, similar to the modern Cascades arc, but we suggest that the arc was composed largely of numerous, very small centers, where magmas frequently leaked up strands of the Sierran frontal fault zone. These small centers erupted to produce andesite lava domes that collapsed to produce block-and-ash flows, which were reworked into paleocanyons as volcanic debris flows and streamflow deposits. Where intrusions rose up through water-saturated paleocanyon fill, they formed peperite complexes that were commonly destabilized to form debris flows. Paleocanyons that were cut into Cretaceous bedrock and filled with Oligocene to late Miocene strata not only provide a stratigraphic record of the ancestral Cascades arc volcanism, but also deep unconformities within them record tectonic events. Preliminary correlation of newly mapped unconformities and new geochronological, magnetostratigraphic, and structural data allow us to propose three episodes of Cenozoic uplift that may correspond to (1) early Miocene onset of arc magmatism (ca. 15 Ma), (2) middle Miocene onset of Basin and Range faulting (ca. 10 Ma), and (3) late Miocene arrival of the triple junction (ca. 6 Ma), perhaps coinciding with a second episode of rapid extension on the range front. Oligocene ignimbrites, which erupted from calderas in central Nevada and filled Sierran paleocanyons, were deeply eroded during the early Miocene uplift event. The middle Miocene event is recorded by growth

  3. Genesis of the vertebrate FoxP subfamily member genes occurred during two ancestral whole genome duplication events. (United States)

    Song, Xiaowei; Tang, Yezhong; Wang, Yajun


    The vertebrate FoxP subfamily genes play important roles in the construction of essential functional modules involved in physiological and developmental processes. To explore the adaptive evolution of functional modules associated with the FoxP subfamily member genes, it is necessary to study the gene duplication process. We detected four member genes of the FoxP subfamily in sea lampreys (a representative species of jawless vertebrates) through genome screenings and phylogenetic analyses. Reliable paralogons (i.e. paralogous chromosome segments) have rarely been detected in scaffolds of FoxP subfamily member genes in sea lampreys due to the considerable existence of HTH_Tnp_Tc3_2 transposases. However, these transposases did not alter gene numbers of the FoxP subfamily in sea lampreys. The coincidence between the "1-4" gene duplication pattern of FoxP subfamily genes from invertebrates to vertebrates and two rounds of ancestral whole genome duplication (1R- and 2R-WGD) events reveal that the FoxP subfamily of vertebrates was quadruplicated in the 1R- and 2R-WGD events. Furthermore, we deduced that a synchronous gene duplication process occurred for the FoxP subfamily and for three linked gene families/subfamilies (i.e. MIT family, mGluR group III and PLXNA subfamily) in the 1R- and 2R-WGD events using phylogenetic analyses and mirror-dendrogram methods (i.e. algorithms to test protein-protein interactions). Specifically, the ancestor of FoxP1 and FoxP3 and the ancestor of FoxP2 and FoxP4 were generated in 1R-WGD event. In the subsequent 2R-WGD event, these two ancestral genes were changed into FoxP1, FoxP2, FoxP3 and FoxP4. The elucidation of these gene duplication processes shed light on the phylogenetic relationships between functional modules of the FoxP subfamily member genes.

  4. Asian Pacific Journal of Tropical Biomedicine

    Institute of Scientific and Technical Information of China (English)


    <正>APJTB Monthly Aims&Scope Asian Pacific Journal of Tropical Biomedicine(APJTB)aims to set up and provide an international academic communication platform for physicians,medical scientists,allied health scientists and public health workers,especially those in the Asian Pacific region and worldwide on tropical biomedicine,infectious diseases and public

  5. Asian Pacific Journal of Tropical Biomedicine

    Institute of Scientific and Technical Information of China (English)


    APJTB MonthlyAims&Scope Asian Pacific Journal of Tropical Biomedicine(APJTB)is administrated by Hainan Medical University and sponsored by Asian Pacific Tropical Medicine Press,and aims to establish an international academic communicating platform for researchers of tropical biomedicine and public health workers,especially specialists and scholars of the Asian

  6. Asian Pacific Journal of Tropical Biomedicine

    Institute of Scientific and Technical Information of China (English)


    Aims & Scope Asian Pacific Journal of TropicalBiomedicine(APJTB) aims to set up and provide an international academic communication plaffom for physicians,medical scientisis,allied health scientists and public health workers,especially those in the Asian Pacific region and worldwide on tropical biomedicine,infectious diseases and public health,and to meet the growing challenges

  7. Asian Pacific Journal of Tropical Biomedicine

    Institute of Scientific and Technical Information of China (English)


    <正>Aims&Scope Asian Pacific Journal of Tropical Biomedicine(APJTB)aims to set up and provide an international academic communication platform for physicians,medical scientists,allied health scientists and public health workers,especially those in the Asian Pacific region and worldwide on tropical biomedicine,infectious diseases and public health,and to meet the growing challenges of understanding

  8. Asian Pacific Journal of Tropical Biomedicine

    Institute of Scientific and Technical Information of China (English)


    APJTB MonthlyAims&Scope Asian Pacific Journal of Tropical Biomedicine(APJTB)aims to set up and provide an international academic communication platform for physicians,medical scientists,allied health scientists and public health workers,especially those in the Asian Pacific region and worldwide on tropical biomedicine,infectious diseases and public health,and to meet the growing challenges

  9. Commonwealth Local Government Forum Pacific Project

    Directory of Open Access Journals (Sweden)

    Terry Parker


    Full Text Available The Commonwealth Local Government Forum (CLGF Pacific Project works with local government and other stakeholders in nine Pacific Island countries – Cook Islands, Fiji Islands, Kiribati, Samoa, Papua New Guinea, Solomon Islands, Tonga, Tuvalu and Vanuatu. It seeks to strengthen local democracy and good governance, and to help local governments deal with the increasing challenges of service delivery and urban management in the unique Pacific environment. Human settlement patterns in the region are changing rapidly. The Pacific has traditionally been a rural agricultural/subsistence society, but this is no longer the case. The accelerated pace of urbanisation has impacted significantly on Pacific nations and in the very near future the majority of Pacific Islanders will be found in urban areas. Already over 50% of Fiji’s population are urban dwellers. Rapid urbanisation brings with it unique challenges and opportunities. Local governments are at the forefront of this phenomenon, with the responsibility to manage urban development and the transition from rural areas to cities and towns. Their success or failure to manage urbanisation and provide the required levels of physical and social infrastructure will affect many lives in a new urban Pacific. The project now has three components – the main Pacific Regional Project and two country-specific programmes: the Honiara City Council Institutional Capacity Building Project and the Commonwealth Local Government Good Practice Scheme in Papua New Guinea.

  10. Atmospheric science: Pacific trade wind intensifier (United States)

    Collier, Mark


    The unprecedented recent intensification of the Pacific trade winds cannot simply be explained by natural variability alone. Now research finds that the more local influence of sulfate aerosols of human and volcanic origin play a significant role, in addition to the Pacific's coupling to the Atlantic Ocean via the 'atmospheric bridge'.

  11. Sedimentological and sequence stratigraphic analysis of Carboniferous deposits in western Libya: Recording the sedimentary response of the northern Gondwana margin to climate and sea-level changes (United States)

    Fröhlich, Sebastian; Petitpierre, Laurent; Redfern, Jonathan; Grech, Paul; Bodin, Stéphane; Lang, Simon


    Detailed sedimentological and sequence stratigraphic analysis of Carboniferous (Tournaisian to Moscovian) strata exposed in the north-western Murzuq Basin and southern Ghadames Basin, western Libya, provides new insights into the sedimentary response of the northern Gondwana margin to climate and sea-level change. The Lower Carboniferous Marar and Assedjefar Formations can be divided into five depositional sequences of 3rd order. In total 27 facies types are defined, grouped into four facies associations: offshore shales, shallow marine clastics, fluvial sandstones and marine carbonates. The bulk of the Lower Carboniferous interval is dominated by an alternation of offshore shales and shallow marine clastics, which were deposited during the transgressive and highstand systems tracts. The clastic deposits mostly consist of laterally persistent coarsening and thickening upward cycles with a common succession from basal hummocky cross-stratified sandstones to ripple-laminated sandstones, capped by multidirectional cross-stratified sandstones. Within the lowstand systems tracts, lenticular sandbodies have been identified, which vary in thickness from 1.5 m (ca. 40 m wide) to 50 m (ca. 1.5 km wide). These are interpreted to be fluvial channel complexes based on their geometry, erosive base, and presence of thick stacked sandstones with unidirectional planar and trough cross-bedding, the absence of bioturbation and occurrence of land plant fragments. These channel complexes mostly cut down into offshore shales, and are interpreted to be bound at the base by sequence boundaries. Palaeogeographic maps generated for each lowstand system show the location and palaeoflow direction of these fluvial channel complexes. They are interpreted to represent large incised valleys filled with thick fluvial sandstones. Their identification and distribution indicates repeated exposure of large areas of western Libya, most-likely controlled by major eustatic sea-level changes. The

  12. The minute brain of the copepod Tigriopus californicus supports a complex ancestral ground pattern of the tetraconate cerebral nervous systems. (United States)

    Andrew, David R; Brown, Sheena M; Strausfeld, Nicholas J


    Copepods are a diverse and ecologically crucial group of minute crustaceans that are relatively neglected in terms of studies on nervous system organization. Recently, morphological neural characters have helped clarify evolutionary relationships within Arthropoda, particularly among Tetraconata (i.e., crustaceans and hexapods), and indicate that copepods occupy an important phylogenetic position relating to both Malacostraca and Hexapoda. This taxon therefore provides the opportunity to evaluate those neural characters common to these two clades likely to be results of shared ancestry (homology) versus convergence (homoplasy). Here we present an anatomical characterization of the brain and central nervous system of the well-studied harpacticoid copepod species Tigriopus californicus. We show that this species is endowed with a complex brain possessing a central complex comprising a protocerebral bridge and central body. Deutocerebral glomeruli are supplied by the antennular nerves, and a lateral protocerebral olfactory neuropil corresponds to the malacostracan hemiellipsoid body. Glomeruli contain synaptic specializations comparable to the presynaptic "T-bars" typical of dipterous insects, including Drosophila melanogaster. Serotonin-like immunoreactivity pervades the brain and ventral nervous system, with distinctive deutocerebral distributions. The present observations suggest that a suite of morphological characters typifying the Tigriopus brain reflect a ground pattern organization of an ancestral Tetraconata, which possessed an elaborate and structurally differentiated nervous system.

  13. Ancestral association between HLA and HFE H63D and C282Y gene mutations from northwest Colombia

    Directory of Open Access Journals (Sweden)

    Libia M Rodriguez


    Full Text Available A significant association between HFE gene mutations and the HLA-A*03-B*07 and HLA-A*29-B*44 haplotypes has been reported in the Spanish population. It has been proposed that these mutations are probably connected with Celtic and North African ancestry, respectively. We aimed to find the possible ancestral association between HLA alleles and haplotypes associated with the HFE gene (C282Y and H63D mutations in 214 subjects from Antioquia, Colombia. These were 18 individuals with presumed hereditary hemochromatosis (“HH” and 196 controls. The HLA-B*07 allele was in linkage disequilibrium (LD with C282Y, while HLA-A*23, A*29, HLA-B*44, and B*49 were in LD with H63D. Altogether, our results show that, although the H63D mutation is more common in the Antioquia population, it is not associated with any particular HLA haplotype, whereas the C282Y mutation is associated with HLA-A*03-B*07, this supporting a northern Spaniard ancestry.

  14. Natural environments, ancestral diets, and microbial ecology: is there a modern "paleo-deficit disorder"? Part II. (United States)

    Logan, Alan C; Katzman, Martin A; Balanzá-Martínez, Vicent


    Famed microbiologist René J. Dubos (1901-1982) was an early pioneer in the developmental origins of health and disease (DOHaD) construct. In the 1960s, he conducted groundbreaking research concerning the ways in which early-life experience with nutrition, microbiota, stress, and other environmental variables could influence later-life health outcomes. He recognized the co-evolutionary relationship between microbiota and the human host. Almost 2 decades before the hygiene hypothesis, he suggested that children in developed nations were becoming too sanitized (vs. our ancestral past) and that scientists should determine whether the childhood environment should be "dirtied up in a controlled manner." He also argued that oft-celebrated growth chart increases via changes in the global food supply and dietary patterns should not be equated to quality of life and mental health. Here in the second part of our review, we reflect the words of Dubos off contemporary research findings in the areas of diet, the gut-brain-axis (microbiota and anxiety and depression) and microbial ecology. Finally, we argue, as Dubos did 40 years ago, that researchers should more closely examine the relevancy of silo-sequestered, reductionist findings in the larger picture of human quality of life. In the context of global climate change and the epidemiological transition, an allergy epidemic and psychosocial stress, our review suggests that discussions of natural environments, urbanization, biodiversity, microbiota, nutrition, and mental health, are often one in the same.

  15. Evolution of the human diet: linking our ancestral diet to modern functional foods as a means of chronic disease prevention. (United States)

    Jew, Stephanie; AbuMweis, Suhad S; Jones, Peter J H


    The evolution of the human diet over the past 10,000 years from a Paleolithic diet to our current modern pattern of intake has resulted in profound changes in feeding behavior. Shifts have occurred from diets high in fruits, vegetables, lean meats, and seafood to processed foods high in sodium and hydrogenated fats and low in fiber. These dietary changes have adversely affected dietary parameters known to be related to health, resulting in an increase in obesity and chronic disease, including cardiovascular disease (CVD), diabetes, and cancer. Some intervention trials using Paleolithic dietary patterns have shown promising results with favorable changes in CVD and diabetes risk factors. However, such benefits may be offset by disadvantages of the Paleolithic diet, which is low in vitamin D and calcium and high in fish potentially containing environmental toxins. More advantageous would be promotion of foods and food ingredients from our ancestral era that have been shown to possess health benefits in the form of functional foods. Many studies have investigated the health benefits of various functional food ingredients, including omega-3 fatty acids, polyphenols, fiber, and plant sterols. These bioactive compounds may help to prevent and reduce incidence of chronic diseases, which in turn could lead to health cost savings ranging from $2 to $3 billion per year as estimated by case studies using omega-3 and plant sterols as examples. Thus, public health benefits should result from promotion of the positive components of Paleolithic diets as functional foods.

  16. Testing the museum versus cradle tropical biological diversity hypothesis: phylogeny, diversification, and ancestral biogeographic range evolution of the ants. (United States)

    Moreau, Corrie S; Bell, Charles D


    Ants are one of the most ecologically and numerically dominant group of terrestrial organisms with most species diversity currently found in tropical climates. Several explanations for the disparity of biological diversity in the tropics compared to temperate regions have been proposed including that the tropics may act as a "museum" where older lineages persist through evolutionary time or as a "cradle" where new species continue to be generated. We infer the molecular phylogenetic relationships of 295 ant specimens including members of all 21 extant subfamilies to explore the evolutionary diversification and biogeography of the ants. By constraining the topology and age of the root node while using 45 fossils as minimum constraints, we converge on an age of 139-158 Mya for the modern ants. Further diversification analyses identified 10 periods with a significant change in the tempo of diversification of the ants, although these shifts did not appear to correspond to ancestral biogeographic range shifts. Likelihood-based historical biogeographic reconstructions suggest that the Neotropics were important in early ant diversification (e.g., Cretaceous). This finding coupled with the extremely high-current species diversity suggests that the Neotropics have acted as both a museum and cradle for ant diversity.

  17. Food-Nonfood Discrimination in Ancestral Vertebrates: Gamete Cannibalism and the Origin of the Adaptive Immune System. (United States)

    Corcos, D


    Adaptive immunity is a complex system that appeared twice in vertebrates (in gnathostomes and in jawless fish) although it is not required for invertebrate defence. The adaptive immune system is tightly associated with self-non-self discrimination, and it is now clear that this interplay is not limited to the prevention of autoreactivity. Micro-organisms are usually considered for their pathogenicity or symbiotic ability, but, for most small metazoans, they mainly constitute food. Vertebrates are characterized by feeding by predation on larger preys, when compared to their ancestors who were filter feeders and ate micro-organisms. Predation gives a strong selective advantage, not only due to the availability of new food resources but also by the ability to eliminate competitors for environmental resources (intraguild predation (IGP)). Unlike size-structured IGP, intraspecific predation of juveniles, zygotes or gametes can be detrimental for species fitness in some circumstances. The ability of individuals to recognize highly polymorphic molecules on the surface of gametes present in the plankton and so distinguish self versus non-self gametes might have constituted a strong selective advantage in intraspecific competition. Here, I propose the theory that the capacity to rearrange receptors has been selected in ancestral vertebrates as a consequence of this strong need for discriminating between hetero-cannibalism versus filial cannibalism. This evolutionary origin sheds light on presently unexplained features of the immune system, including the existence of regulatory T cells and of non-pathogenic natural autoimmunity.

  18. Ancestral variation and the potential for genetic accommodation in larval amphibians: implications for the evolution of novel feeding strategies. (United States)

    Ledon-Rettig, Cris C; Pfennig, David W; Nascone-Yoder, Nanette


    Few studies provide empirical evidence for phenotypic plasticity's role in the evolution of novel traits. One way to do so is to test whether latent plasticity is present in an ancestor that can be refined, enhanced, or diminished by selection in derived taxa (through "genetic accommodation"), thereby producing novel traits. Here, we evaluated whether gut plasticity preceded and promoted the evolution of a novel feeding strategy in spadefoot toad tadpoles. We studied Scaphiopus couchii, whose tadpoles develop an elongate gut and consume only detritus, and two derived species, Spea multiplicata and Sp. bombifrons, whose tadpoles also express a novel, short-gut phenotype in response to a novel resource (anostracan shrimp). Consistent with the expectations of plasticity-mediated trait evolution, we found that shrimp induced a range of phenotypes in Scaphiopus that were not produced with detritus. This plasticity was either suppressed or exaggerated in Spea depending on whether the induced phenotypes were adaptive. Moreover, in contrast to its effects on morphology, shrimp induced little or no functional plasticity, as assessed by gut cell proliferation, in Scaphiopus. Shrimp did, however, induce substantial proliferation in Sp. bombifrons, the species that consumes the most shrimp and that produces the short-gut phenotype the most frequently. Thus, if Spea had ancestral morphological plasticity in response to a novel diet, their shrimp-induced short-gut morphology may have undergone subsequent genetic accommodation that improved its functionality. Hence, diet-induced phenotypic plasticity may have preceded and even promoted the evolution of a novel phenotype.

  19. Facial anatomy of Victoriapithecus and its relevance to the ancestral cranial morphology of Old World monkeys and apes. (United States)

    Benefit, B R; McCrossin, M L


    Recently discovered craniofacial fossils of the middle Miocene cercopithecoid Victoriapithecus are described. The frontal, zygomatic, maxilla, and premaxilla anatomy differ from the previously proposed colobine-like ancestral cercopithecoid morphotype in several significant respects. This morphotype was based on the assumption that features held in common by subordinate hominoid and cercopithecoid morphotypes (Colobinae and Hylobatidae) are primitive for Old World monkeys. Cranial similarities between Victoriapithecus, which represents the sister-group of both colobine and cercopithecine monkeys, and the shorter-snouted Cercopithecinae (Macaca and Cercopithecus) indicate that the last common ancestor of Old World monkeys possessed the following features: a narrow interorbital septum, moderately long snout, moderately long and anteriorly tapering premaxilla, large procumbent upper central incisors set anterior to and with longer roots than lateral incisors, moderately tall face below the orbits, teardrop-shaped nasal aperture of low height and moderate width, and probably long and narrow nasal bones. The Victoriapithecus cranium is also characterized by features not present in modern cercopithecids. These include a deep malar region of the zygomatic and the presence of a frontal trigon due to the occurrence of temporal lines that merge with supraorbital costae close to the midline of each orbit and converge anterior to bregma. These features are interpreted as primitive retentions from the basal catarrhine condition as indicated by the occurrence of these features among primitive catarrhines (Aegyptopithecus) and Miocene hominoids (Afropithecus).

  20. Natural epigenetic protection against the I-factor, a Drosophila LINE retrotransposon, by remnants of ancestral invasions. (United States)

    Dramard, Xavier; Heidmann, Thierry; Jensen, Silke


    Transposable elements are major components of most eukaryotic genomes. Such sequences are generally defective for transposition and have little or no coding capacity. Because transposition can be highly mutagenic, mobile elements that remain functional are tightly repressed in all living species. Drosophila pericentromeric heterochromatin naturally contains transposition-defective, non-coding derivatives of a LINE retrotransposon related to the I-factor. The I-factor is a good model to study the regulation of transposition in vivo because, under specific conditions, current functional copies of this mobile element can transpose at high frequency, specifically in female germ cells, with deleterious effects including female sterility. However, this high transpositional activity becomes spontaneously repressed upon ageing or heat treatment, by a maternally transmitted, transgenerational epigenetic mechanism of unknown nature. We have analyzed, by quantitative real time RT-PCR, the RNA profile of the transposition-defective I-related sequences, in the Drosophila ovary during ageing and upon heat treatment, and also in female somatic tissues and in males, which are not permissive for I-factor transposition. We found evidence for a role of transcripts from these ancestral remnants in the natural epigenetic protection of the Drosophila melanogaster genome against the deleterious effects of new invasions by functional I-factors. These results provide a molecular basis for a probably widespread natural protection against transposable elements by persisting vestiges of ancient invasions.

  1. What was the ancestral function of decidual stromal cells? A model for the evolution of eutherian pregnancy. (United States)

    Chavan, Arun Rajendra; Bhullar, Bhart-Anjan S; Wagner, Günter P


    In human and mouse, decidual stromal cells (DSC) are necessary for the establishment (implantation) and the maintenance of pregnancy by preventing inflammation and the immune rejection of the semi-allograft conceptus. DSC originated along the stem lineage of eutherian mammals, coincidental with the origin of invasive placentation. Surprisingly, in many eutherian lineages decidual cells are lost after the implantation phase of pregnancy, making it unlikely that DSC are necessary for the maintenance of pregnancy in these animals. In order to understand this variation, we review the literature on the fetal-maternal interface in all major eutherian clades Euarchontoglires, Laurasiatheria, Xenarthra and Afrotheria, as well as the literature about the ancestral eutherian species. We conclude that maintaining pregnancy may not be a shared derived function of DSC among all eutherian mammals. Rather, we propose that DSC originated to manage the inflammatory reaction associated with invasive implantation. We envision that this happened in a stem eutherian that had invasive placenta but still a short gestation. We further propose that extended gestation evolved independently in the major eutherian clades explaining why the major lineages of eutherian mammals differ with respect to the mechanisms maintaining pregnancy.

  2. Cochlear gene therapy with ancestral AAV in adult mice: complete transduction of inner hair cells without cochlear dysfunction (United States)

    Suzuki, Jun; Hashimoto, Ken; Xiao, Ru; Vandenberghe, Luk H.; Liberman, M. Charles


    The use of viral vectors for inner ear gene therapy is receiving increased attention for treatment of genetic hearing disorders. Most animal studies to date have injected viral suspensions into neonatal ears, via the round window membrane. Achieving transduction of hair cells, or sensory neurons, throughout the cochlea has proven difficult, and no studies have been able to efficiently transduce sensory cells in adult ears while maintaining normal cochlear function. Here, we show, for the first time, successful transduction of all inner hair cells and the majority of outer hair cells in an adult cochlea via virus injection into the posterior semicircular canal. We used a “designer” AAV, AAV2/Anc80L65, in which the main capsid proteins approximate the ancestral sequence state of AAV1, 2, 8, and 9. Our injections also transduced ~10% of spiral ganglion cells and a much larger fraction of their satellite cells. In the vestibular sensory epithelia, the virus transduced large numbers of hair cells and virtually all the supporting cells, along with close to half of the vestibular ganglion cells. We conclude that this viral vector and this delivery route hold great promise for gene therapy applications in both cochlear and vestibular sense organs. PMID:28367981

  3. Hox Proteins Display a Common and Ancestral Ability to Diversify Their Interaction Mode with the PBC Class Cofactors (United States)

    Hudry, Bruno; Remacle, Sophie; Delfini, Marie-Claire; Rezsohazy, René; Graba, Yacine; Merabet, Samir


    Hox transcription factors control a number of developmental processes with the help of the PBC class proteins. In vitro analyses have established that the formation of Hox/PBC complexes relies on a short conserved Hox protein motif called the hexapeptide (HX). This paradigm is at the basis of the vast majority of experimental approaches dedicated to the study of Hox protein function. Here we questioned the unique and general use of the HX for PBC recruitment by using the Bimolecular Fluorescence Complementation (BiFC) assay. This method allows analyzing Hox-PBC interactions in vivo and at a genome-wide scale. We found that the HX is dispensable for PBC recruitment in the majority of investigated Drosophila and mouse Hox proteins. We showed that HX-independent interaction modes are uncovered by the presence of Meis class cofactors, a property which was also observed with Hox proteins of the cnidarian sea anemone Nematostella vectensis. Finally, we revealed that paralog-specific motifs convey major PBC-recruiting functions in Drosophila Hox proteins. Altogether, our results highlight that flexibility in Hox-PBC interactions is an ancestral and evolutionary conserved character, which has strong implications for the understanding of Hox protein functions during normal development and pathologic processes. PMID:22745600

  4. Hox proteins display a common and ancestral ability to diversify their interaction mode with the PBC class cofactors.

    Directory of Open Access Journals (Sweden)

    Bruno Hudry

    Full Text Available Hox transcription factors control a number of developmental processes with the help of the PBC class proteins. In vitro analyses have established that the formation of Hox/PBC complexes relies on a short conserved Hox protein motif called the hexapeptide (HX. This paradigm is at the basis of the vast majority of experimental approaches dedicated to the study of Hox protein function. Here we questioned the unique and general use of the HX for PBC recruitment by using the Bimolecular Fluorescence Complementation (BiFC assay. This method allows analyzing Hox-PBC interactions in vivo and at a genome-wide scale. We found that the HX is dispensable for PBC recruitment in the majority of investigated Drosophila and mouse Hox proteins. We showed that HX-independent interaction modes are uncovered by the presence of Meis class cofactors, a property which was also observed with Hox proteins of the cnidarian sea anemone Nematostella vectensis. Finally, we revealed that paralog-specific motifs convey major PBC-recruiting functions in Drosophila Hox proteins. Altogether, our results highlight that flexibility in Hox-PBC interactions is an ancestral and evolutionary conserved character, which has strong implications for the understanding of Hox protein functions during normal development and pathologic processes.

  5. 论家族祠堂文化的教育与传承--以博白客家家族祠堂为例%Cultural Education and Inheritance of Family Ancestral Temple-- Take Bobai Hakka Family Ancestral Temple County as an Example

    Institute of Scientific and Technical Information of China (English)

    李春霞; 程丽秋


    祠堂是家族的中心和家族文化的载体,它践行着家族文化的教育与传承的重要使命。博白县客家的家族文化氛围特别浓厚,本文以其为例,论述博白客家祠堂文化及其教育与传承的方式。家族祠堂文化对可塑性极强的儿童的影响方式有环境熏陶、榜样示范以及教育期望等等,即论述家族祠堂文化的教育与传承,需要家族充分利用祠堂这个载体进行家族教育,以实现祠堂教育功能最大化的发挥。%Family ancestral temple is the center of the family and the isotopic carrier of family culture. It sustains the responsibility of the education and inheritance of family culture. Bobai county is selected as an example because Bobai Hakka people have a strong concept of family. This paper discusses culture, education and inheritance of the Hakka family ancestral temple culture in Bobai county. The culture of family ancestral temple has an influence on educable child and the influence way include environmental edifying, model demonstrating and educational expectation, etc. It needs the family to make full use of the isotopic carrier of the ancestral temple to educate the descendants when discussing the cultural education and inheritance of family ancestral temple. It aims to maximize the educational function of ancestral temple education.

  6. The Tectonic Event of the Cenozoic in the Tasman Area, Western Pacific, and Its Role in Eocene Global Change (United States)

    Collot, J.; Sutherland, R.; Rouillard, P.; Patriat, M.; Roest, W. R.; Bache, F.


    The geometry and age progression of Emperor and Hawaii seamounts provide compelling evidence for a major change in Pacific plate motion over a short period of geological time at c. 50 Ma. This time approximately coincides with significant changes in plate boundary configuration and rate in the Indian Ocean, Antarctica, and with the onset of subduction zones in the western Pacific from Japan to New Zealand. This new subduction system that initiated during Eocene time can be divided into two sectors: The northern sector formed at the eastern boundary of the Philippine Sea plate and evolved into the Izu-Bonin-Mariana system. It has and is being extensively studied (2014 IODP expedition 351) to determine the magmatic products, but is limited in the record that is preserved because it is entirely intra-oceanic in character. The southern sector, the Tasman Area sector, borders continental fragments of Gondwana from Papua New Guinea, New Caledonia and New Zealand. This subduction zone evolved into the Tonga-Kemadec system. Because most of the southwest Pacific remained in marine conditions throughout Paleogene time and because rapid seawards roll-back of the subduction is inferred to have happened, it presents extensive well-preserved stratigraphic records to study the Eocene-Oligocene plate boundary evolution. The recent compilation of c. 100.000 km of 2D seismic data in the Tasman Frontier database has allowed us to describe, in the overriding plate of the proto subduction, stratigraphic evidence for large Cenozoic vertical movements (2-4 km) over a lateral extension of 2000 km (from New Caledonia to New Zealand), long-wavelength (~500 km) warping and large amounts of reverse faulting and folding near the proto-trench. These recent observations from the Lord Howe Rise, New Caledonia Trough and South Norfolk Ridge system reveal clear evidence for convergent deformation (uplift and erosion) and subsequent subsidence recorded in Eocene and Oligocene stratal relationships

  7. Creation of Functional Viruses from Non-Functional cDNA Clones Obtained from an RNA Virus Population by the Use of Ancestral Reconstruction

    DEFF Research Database (Denmark)

    Fahnøe, Ulrik; Pedersen, Anders Gorm; Dräger, Carolin;


    the reconstructed cDNAs were tested in cell culture and pigs. Both reconstructed ancestral genomes proved functional, and displayed distinct phenotypes in vitro and in vivo. We suggest that reconstruction of ancestral viruses is a useful tool for experimental and computational investigations of virulence and viral......RNA viruses have the highest known mutation rates. Consequently it is likely that a high proportion of individual RNA virus genomes, isolated from an infected host, will contain lethal mutations and be non-functional. This is problematic if the aim is to clone and investigate high...... a moderately virulent isolate. In addition to here being used as a model for RNA viruses generally, CSFV has high socioeconomic importance and remains a threat to animal welfare and pig production. We find that the majority of the investigated genomes are non-functional and only 12% produced infectious RNA...

  8. The pig story (tiboi sakkoko Storytelling of kinship, memories of the past, and rights to plots of ancestral land in Mentawai

    Directory of Open Access Journals (Sweden)

    Juniator Tulius


    Full Text Available This paper examines some significant elements of the pig story (tiboi sakkoko. This tale contains crucial information about the collective identity, ancestors and historical events affecting particular Mentawai kin-groups. As families do not preserve their culture and traditions in written form, storytellers of kin-groups have narrated the pig story from generation to generation so as to preserve it carefully. In the course of time, storytellers establish particular ways of telling their stories so as to remember the content and plot of the stories easily. Through the pig story, members of kin groups also recollect their ancestral place of origin and plots of ancestral lands. The role of human memory is indispensable to recalling all these important elements. Therefore, this paper analyses memories of the past of different family generations. To achieve its aims, this paper also evaluates the roles of family stories in the culture and traditions of Mentawai society.

  9. Clan, ancestral hall, and sacrifice in the Song Dynasty%宋代的宗族祠堂、祭祀及其它

    Institute of Scientific and Technical Information of China (English)



    The Song Dynasty is the most important period in Chinese history in terms of the establishment of a new type of clan system. During the Song, Chinese social organization, at the grass-roots level, experienced a fundamental change.In the wake of the late-Tang collapse of the local power system, it was necessary for the Song to replace the ancestral lineage structure and develop a new system to adapt itself to the new circumstances brought on by drastic changes in its economy. Song Confucians played a vital part in the changes. Not only did they gradually solve the theoretical problems of the new type of clan organization, but they also developed many feasible and standard models. Eventually this model would gain even wider acceptance after the Yuan Dynasty with the rise of Neo-Confucianism. Thus, ancestral halls, serving as the major centers for the new clan activities, became prevalent among common people.

  10. The Chachil Limestone (Pliensbachian-earliest Toarcian) Neuquén Basin, Argentina: U-Pb age calibration and its significance on the Early Jurassic evolution of southwestern Gondwana (United States)

    Leanza, H. A.; Mazzini, A.; Corfu, F.; Llambías, E. J.; Svensen, H.; Planke, S.; Galland, O.


    New radiometric U-Pb ages obtained on zircon crystals from Early Jurassic ash layers found within beds of the Chachil Limestone at its type locality in the Chachil depocentre (southern Neuquén Basin) confirm a Pliensbachian age (186.0 ± 0.4 Ma). Additionally, two ash layers found in limestone beds in Chacay Melehue at the Cordillera del Viento depocentre (central Neuquén Basin) gave Early Pliensbachian (185.7 ± 0.4 Ma) and earliest Toarcian (182.3 ± 0.4 Ma) U-Pb zircon ages. Based on these new datings and regional geological observations, we propose that the limestones cropping out at Chacay Melehue are correlatable with the Chachil Limestone. Recent data by other authors from limestones at Serrucho creek in the upper Puesto Araya Formation (Valenciana depocentre, southern Mendoza) reveal ages of 182.16 ± 0.6 Ma. Based on these new evidences, we consider the Chachil Limestone an important Early Jurassic stratigraphic marker, representing an almost instantaneous widespread flooding episode in western Gondwana. The unit marks the initiation in the Neuquén Basin of the Cuyo Group, followed by widespread black shale deposition. Accordingly, these limestones can be regarded as the natural seal of the Late Triassic -earliest Jurassic Precuyano Cycle, which represents the infill of halfgrabens and/or grabens related to a strong extensional regime. Paleontological evidence supports that during Pliensbachian-earliest Toarcian times these limestones were deposited in western Gondwana in marine warm water environments.

  11. Petrología y geoquímica de los granitoides peralumínicos de la Faja TIPA, en el borde occidental de Gondwana, sistema de Famatina, Argentina

    Directory of Open Access Journals (Sweden)

    Toselli, A. J.


    Full Text Available Main pretrological and geochemistry characteristics of the rocks of Copacabana, Paimán and Velasco Ranges are shown, constituent of the important deformative structure developed in the east border of Famatinian System. This structure is relationed with Ocloyic-Taconic Collision between Gondwana and Laurentia, during Upper Ordovicic-Lower Siluric and Lower Carbonic, in response to a compressive regimen with vergence to the East.En este trabajo se presentan las principales características petrográficas y geoquímicas de las rocas que constituyen las Sierra de Copacabana, flanco oriental de la Sierra de Paimán y extremo NW de la Sierra de Velasco, dentro de la importante estructura deformativa que se desarrolla en el borde oriental del Sistema de Famatina y da lugar a la Faja Deformada TIPA. Tales rocas corresponden a una tendencia evolutiva de características calcoalcalinas y son netamente peraluminosas, con presencia de minerales como biotita, muscovita, sillimanita, cianita, cordierita y granate. Esta estructura se vincularía con la colisión oclóyica-tacónica entre Gondwana y Laurentia (Dalla Salda el al., 1993 en niveles no muy profundos de la corteza, dentro de un ambiente tectónico transicional entre regiones de arco volcánico y sin-colisional. Este evento colisional habría tenido lugar entre el Ordovícico superior-Silúrico inferior y el Carbónico inferior, respondiendo a un régimen compresivo con vergencia al E.

  12. Long-lasting Cadomian magmatic activity along an active northern Gondwana margin: U-Pb zircon and Sr-Nd isotopic evidence from the Brunovistulian Domain, eastern Bohemian Massif (United States)

    Soejono, Igor; Janoušek, Vojtěch; Žáčková, Eliška; Sláma, Jiří; Konopásek, Jiří; Machek, Matěj; Hanžl, Pavel


    Cadomian magmatic complexes of the Brunovistulian Domain crop out at the eastern termination of the Bohemian Massif. However, the age, nature and geotectonic affinity of some of pre-Variscan (meta-)igneous rock complexes from this domain are still unknown. Geochronological and geochemical study of the granitic rocks across the Brunovistulian Domain reveals new information about the timing and nature of this magmatic activity originally situated along the northern margin of Gondwana. Zircon U-Pb data (601 ± 3 Ma, Brno Massif; 634 ± 6 Ma, paraautochtonous core of the Svratka Dome; 568 ± 3 Ma, Bíteš orthogneiss) from the allochtonous Moravicum indicate the prolonged magmatic activity within the Brunovistulian Domain during the Ediacaran. The major- and trace-element and Sr-Nd isotopic signatures show heterogeneous geochemical characteristics of the granitic rocks and suggest a magmatic-arc geotectonic setting. The two-stage Depleted Mantle Nd model ages (c. 1.3-2.0 Ga) indicate derivation of the granitic rocks from a relatively primitive crustal source, as well as from an ancient and evolved continental crust of the Brunovistulian Domain. These results constrain the magmatic-arc activity to c. 635-570 Ma and provide a further evidence for a long-lived (at least c. 65 Myr) and likely episodic subduction-related magmatism at the northern margin of Gondwana. The presence of granitic intrusions derived from variously mature crustal sources at different times suggests heterogeneous crustal segments to having been involved in the magmatic-arc system during its multistage evolution.

  13. Asian Pacific Journal of Tropical Biomedicine

    Institute of Scientific and Technical Information of China (English)


    <正>Aims&Scope Asian Pacific Journal of Tropical Biomedicine(APJTB)aims to set up and provide an international academic communication platform for physicians,medical scientists,allied health scientists and public health workers,especially those in the Asian Pacific region and worldwide on tropical biomedicine,infectious diseases and public health,and to meet the growing challenges of understanding,preventing and controlling the dramatic global emergence and reemergence of infectious diseases in the Asian Pacific region.APJTB publishes new findings in both basic and clinical(including modern,traditional and epidemiological)research

  14. Geological history of the Western north pacific. (United States)

    Fischer, A G; Heezen, B C; Boyce, R E; Bury, D; Douglas, R G; Garrison, R E; Kling, S A; Krasheninnikov, V; Lisitzin, A P; Pimm, A C


    A considerable portion of the abyssal floor of the western North Pacific was already receiving pelagic sediment in late Jurassic time. Carbonate sediments were later replaced by abyssal clays as the basin deepened and bottom waters became more aggressive. The resulting facies boundary, which can be recognized on seismic profiles, is broadly transgressive; it ranges in age from mid-Cretaceous in the western Pacific to Oligocene in the central Pacific. Cherts are encountered at and below the major facies boundary and appear to have been formed by postdepositional processes.

  15. Los no lugares y el mundo de las aguas: Aproximación al territorio ancestral de una comunidad amazónica



    Characterization of an ancestral territory of the indigenous community of Macedonia was performed (Colombian Amazon located 57 km upstream from Leticia); through the cultural maps analysis obtained of ethnographic methodology based on social mapping and one analysis through intersubjective processes of consensus.As a result, georeferenced maps that generate an approximation of non-places that give access to shamanistic macro-space were obtained, which in turn is used to generate a local cultu...

  16. Phylogenomic analysis of vertebrate thrombospondins reveals fish-specific paralogues, ancestral gene relationships and a tetrapod innovation

    Directory of Open Access Journals (Sweden)

    Adams Josephine C


    Full Text Available Abstract Background Thrombospondins (TSPs are evolutionarily-conserved, extracellular, calcium-binding glycoproteins with important roles in cell-extracellular matrix interactions, angiogenesis, synaptogenesis and connective tissue organisation. Five TSPs, designated TSP-1 through TSP-5, are encoded in the human genome. All but one have known roles in acquired or inherited human diseases. To further understand the roles of TSPs in human physiology and pathology, it would be advantageous to extend the repertoire of relevant vertebrate models. In general the zebrafish is proving an excellent model organism for vertebrate biology, therefore we set out to evaluate the status of TSPs in zebrafish and two species of pufferfish. Results We identified by bioinformatics that three fish species encode larger numbers of TSPs than vertebrates, yet all these sequences group as homologues of TSP-1 to -4. By phylogenomic analysis of neighboring genes, we uncovered that, in fish, a TSP-4-like sequence is encoded from the gene corresponding to the tetrapod TSP-5 gene. Thus, all TSP genes show conservation of synteny between fish and tetrapods. In the human genome, the TSP-1, TSP-3, TSP-4 and TSP-5 genes lie within paralogous regions that provide insight into the ancestral genomic context of vertebrate TSPs. Conclusion A new model for TSP evolution in vertebrates is presented. The TSP-5 protein sequence has evolved rapidly from a TSP-4-like sequence as an innovation in the tetrapod lineage. TSP biology in fish is complicated by the presence of additional lineage- and species-specific TSP paralogues. These novel results give deeper insight into the evolution of TSPs in vertebrates and open new directions for understanding the physiological and pathological roles of TSP-4 and TSP-5 in humans.

  17. Somatostatin signaling system as an ancestral mechanism: Myoregulatory activity of an Allatostatin-C peptide in Hydra. (United States)

    Alzugaray, María Eugenia; Hernández-Martínez, Salvador; Ronderos, Jorge Rafael


    The coordination of physiological processes requires precise communication between cells. Cellular interactions allow cells to be functionally related, facilitating the maintaining of homeostasis. Neuropeptides functioning as intercellular signals are widely distributed in Metazoa. It is assumed that neuropeptides were the first intercellular transmitters, appearing early during the evolution. In Cnidarians, neuropeptides are mainly involved in neurotransmission, acting directly or indirectly on epithelial muscle cells, and thereby controlling coordinated movements. Allatostatins are a group of chemically unrelated neuropeptides that were originally characterized based on their ability to inhibit juvenil hormone synthesis in insects. Allatostatin-C has pleiotropic functions, acting as myoregulator in several insects. In these studies, we analyzed the myoregulatory effect of Aedes aegypti Allatostatin-C in Hydra sp., a member of the phylum Cnidaria. Allatostatin-C peptide conjugated with Qdots revealed specifically distributed cell populations that respond to the peptide in different regions of hydroids. In vivo physiological assays using Allatostatin-C showed that the peptide induced changes in shape and length in tentacles, peduncle and gastrovascular cavity. The observed changes were dose and time dependent suggesting the physiological nature of the response. Furthermore, at highest doses, Allatostatin-C induced peristaltic movements of the gastrovascular cavity resembling those that occur during feeding. In silico search of putative Allatostatin-C receptors in Cnidaria showed that genomes predict the existence of proteins of the somatostatin/Allatostatin-C receptors family. Altogether, these results suggest that Allatostatin-C has myoregulatory activity in Hydra sp, playing a role in the control of coordinated movements during feeding, indicating that Allatostatin-C/Somatostatin based signaling might be an ancestral mechanism.

  18. Phylogenetic analysis of glycerol 3-phosphate acyltransferases in opisthokonts reveals unexpected ancestral complexity and novel modern biosynthetic components.

    Directory of Open Access Journals (Sweden)

    Heather C Smart

    Full Text Available Glycerolipid synthesis represents a central metabolic process of all forms of life. In the last decade multiple genes coding for enzymes responsible for the first step of the pathway, catalyzed by glycerol 3-phosphate acyltransferase (GPAT, have been described, and characterized primarily in model organisms like Saccharomyces cerevisiae and mice. Notoriously, the fungal enzymes share low sequence identity with their known animal counterparts, and the nature of their homology is unclear. Furthermore, two mitochondrial GPAT isoforms have been described in animal cells, while no such enzymes have been identified in Fungi. In order to determine if the yeast and mammalian GPATs are representative of the set of enzymes present in their respective groups, and to test the hypothesis that metazoan orthologues are indeed absent from the fungal clade, a comparative genomic and phylogenetic analysis was performed including organisms spanning the breadth of the Opisthokonta supergroup. Surprisingly, our study unveiled the presence of 'fungal' orthologs in the basal taxa of the holozoa and 'animal' orthologues in the basal holomycetes. This includes a novel clade of fungal homologues, with putative peroxisomal targeting signals, of the mitochondrial/peroxisomal acyltransferases in Metazoa, thus potentially representing an undescribed metabolic capacity in the Fungi. The overall distribution of GPAT homologues is suggestive of high relative complexity in the ancestors of the opisthokont clade, followed by loss and sculpting of the complement in the descendent lineages. Divergence from a general versatile metabolic model, present in ancestrally deduced GPAT complements, points to distinctive contributions of each GPAT isoform to lipid metabolism and homeostasis in contemporary organisms like humans and their fungal pathogens.

  19. Amoebozoans Are Secretly but Ancestrally Sexual: Evidence for Sex Genes and Potential Novel Crossover Pathways in Diverse Groups of Amoebae (United States)

    Wood, Fiona C.; Katz, Laura A.; Cerón-Romero, Mario A.; Gorfu, Lydia A.


    Sex is beneficial in eukaryotes as it can increase genetic diversity, reshuffle their genomes, and purge deleterious mutations. Yet, its evolution remains a mystery. The eukaryotic clade supergroup Amoebozoa encompasses diverse lineages of polymorphic amoeboid forms, including both free-living and parasitic lineages. The group is generally believed to be asexual, though recent studies show that some of its members are implicated in cryptic forms of sexual cycles. In this study, we conduct a comprehensive inventory and analysis of genes involved in meiosis and related processes, in order to investigate the evolutionary history of sex in the clade. We analyzed genomic and transcriptomic data of 39 amoebozoans representing all major subclades of Amoebozoa. Our results show that Amoebozoa possess most of the genes exclusive to meiosis but lack genes encoding synaptonemal complex (SC). The absence of SC genes is discussed in the context of earlier studies that reported ultrastructural evidence of SC in some amoebae. We also find interclade and intrageneric variation in sex gene distribution, indicating diversity in sexual pathways in the group. Particularly, members of Mycetozoa engage in a novel sexual pathway independent of the universally conserved meiosis initiator gene, SPO11. Our findings strongly suggest that not only do amoebozoans possess sex genes in their genomes, but also, based on the transcriptome evidence, the present sex genes are functional. We conclude that Amoebozoa is ancestrally sexual, contrary to the long held belief that most of its members are asexual. Thus, asexuality in Amoebozoa, if confirmed to be present, is a derived-trait that appeared later in their evolution. PMID:28087686

  20. Genome-wide association study and ancestral origins of the slick-hair coat in tropically adapted cattle. (United States)

    Huson, Heather J; Kim, Eui-Soo; Godfrey, Robert W; Olson, Timothy A; McClure, Matthew C; Chase, Chad C; Rizzi, Rita; O'Brien, Ana M P; Van Tassell, Curt P; Garcia, José F; Sonstegard, Tad S


    The slick hair coat (SLICK) is a dominantly inherited trait typically associated with tropically adapted cattle that are from Criollo descent through Spanish colonization of cattle into the New World. The trait is of interest relative to climate change, due to its association with improved thermo-tolerance and subsequent increased productivity. Previous studies localized the SLICK locus to a 4 cM region on chromosome (BTA) 20 and identified signatures of selection in this region derived from Senepol cattle. The current study compares three slick-haired Criollo-derived breeds including Senepol, Carora, and Romosinuano and three additional slick-haired cross-bred lineages to non-slick ancestral breeds. Genome-wide association (GWA), haplotype analysis, signatures of selection, runs of homozygosity (ROH), and identity by state (IBS) calculations were used to identify a 0.8 Mb (37.7-38.5 Mb) consensus region for the SLICK locus on BTA20 in which contains SKP2 and SPEF2 as possible candidate genes. Three specific haplotype patterns are identified in slick individuals, all with zero frequency in non-slick individuals. Admixture analysis identified common genetic patterns between the three slick breeds at the SLICK locus. Principal component analysis (PCA) and admixture results show Senepol and Romosinuano sharing a higher degree of genetic similarity to one another with a much lesser degree of similarity to Carora. Variation in GWA, haplotype analysis, and IBS calculations with accompanying population structure information supports potentially two mutations, one common to Senepol and Romosinuano and another in Carora, effecting genes contained within our refined location for the SLICK locus.

  1. Expansion and Functional Divergence of Jumonji C-Containing Histone Demethylases: Significance of Duplications in Ancestral Angiosperms and Vertebrates. (United States)

    Qian, Shengzhan; Wang, Yingxiang; Ma, Hong; Zhang, Liangsheng


    Histone modifications, such as methylation and demethylation, are crucial mechanisms altering chromatin structure and gene expression. Recent biochemical and molecular studies have uncovered a group of histone demethylases called Jumonji C (JmjC) domain proteins. However, their evolutionary history and patterns have not been examined systematically. Here, we report extensive analyses of eukaryotic JmjC genes and define 14 subfamilies, including the Lysine-Specific Demethylase3 (KDM3), KDM5, JMJD6, Putative-Lysine-Specific Demethylase11 (PKDM11), and PKDM13 subfamilies, shared by plants, animals, and fungi. Other subfamilies are detected in plants and animals but not in fungi (PKDM12) or in animals and fungi but not in plants (KDM2 and KDM4). PKDM7, PKDM8, and PKDM9 are plant-specific groups, whereas Jumonji, AT-Rich Interactive Domain2, KDM6, and PKDM10 are animal specific. In addition to known domains, most subfamilies have characteristic conserved amino acid motifs. Whole-genome duplication (WGD) was likely an important mechanism for JmjC duplications, with four pairs from an angiosperm-wide WGD and others from subsequent WGDs. Vertebrates also experienced JmjC duplications associated with the vertebrate ancestral WGDs, with additional mammalian paralogs from tandem duplication and possible transposition. The sequences of paralogs have diverged in both known functional domains and other regions, showing evidence of selection pressure. The increases of JmjC copy number and the divergences in sequence and expression might have contributed to the divergent functions of JmjC genes, allowing the angiosperms and vertebrates to adapt to a great number of ecological niches and contributing to their evolutionary successes.

  2. Genome-wide association study and ancestral origins of the slick-hair coat in tropically adapted cattle

    Directory of Open Access Journals (Sweden)

    Heather Jay Huson


    Full Text Available The slick hair coat (SLICK is a dominantly inherited trait typically associated with tropically adapted cattle that are from Criollo descent through Spanish colonization of cattle into the New World. The trait is of interest relative to climate change, due to its association with improved thermo-tolerance and subsequent increased productivity. Previous studies localized the SLICK locus to a 4 cM region on chromosome (Chr 20 and identified signatures of selection in this region derived from Senepol cattle. The current study compares three slick-haired Criollo-derived breeds including Senepol, Carora, and Romosinuano and three additional slick-haired cross-bred lineages to non-slick ancestral breeds. Genome-wide association (GWA, haplotype analysis, signatures of selection, runs of homozygosity, and identity by state (IBS calculations were used to identify a 0.8Mb (37.7-38.5Mb consensus region for the SLICK locus on Chr 20 in which contains SKP2 and SPEF2 as possible candidate genes. Three specific haplotype patterns are identified in slick individuals, all with zero frequency in non-slick individuals. Admixture analysis identified common genetic patterns between the three slick breeds at the SLICK locus. Principle component analysis and admixture results show Senepol and Romosinuano sharing a higher degree of genetic similarity to one another with a much lesser degree of similarity to Carora. Variation in GWA, haplotype analysis, and IBS calculations with accompanying population structure information supports potentially two mutations, one common to Senepol and Romosinuano and another in Carora, effecting genes contained within our refined location for the SLICK locus.

  3. Surgeons and suture zones: Hybridization among four surgeonfish species in the Indo-Pacific with variable evolutionary outcomes

    KAUST Repository

    DiBattista, Joseph


    Closely related species can provide valuable insights into evolutionary processes through comparison of their ecology, geographic distribution and the history recorded in their genomes. In the Indo-Pacific, many reef fishes are divided into sister species that come into secondary contact at biogeographic borders, most prominently where Indian Ocean and Pacific Ocean faunas meet. It is unclear whether hybridization in this contact zone represents incomplete speciation, secondary contact, an evolutionary dead-end (for hybrids) or some combination of the above. To address these issues, we conducted comprehensive surveys of two widely-distributed surgeonfish species, Acanthurus leucosternon (N = 141) and A. nigricans (N = 412), with mtDNA cytochrome b sequences and ten microsatellite loci. These surgeonfishes are found primarily in the Indian and Pacific Oceans, respectively, but overlap at the Christmas and Cocos-Keeling Islands hybrid zone in the eastern Indian Ocean. We also sampled the two other Pacific members of this species complex, A. achilles (N = 54) and A. japonicus (N = 49), which are known to hybridize with A. nigricans where their ranges overlap. Our results indicate separation between the four species that range from the recent Pleistocene to late Pliocene (235,000 to 2.25 million years ago). The Pacific A. achilles is the most divergent (and possibly ancestral) species with mtDNA dcorr ≈ 0.04, whereas the other two Pacific species (A. japonicus and A. nigricans) are distinguishable only at a population or subspecies level (ΦST = 0.6533, P < 0.001). Little population structure was observed within species, with evidence of recent population expansion across all four geographic ranges. We detected sharing of mtDNA haplotypes between species and extensive hybridization based on microsatellites, consistent with later generation hybrids but also the effects of allele homoplasy. Despite extensive introgression, 98% of specimens had concordance between mt

  4. Surgeons and suture zones: Hybridization among four surgeonfish species in the Indo-Pacific with variable evolutionary outcomes. (United States)

    DiBattista, Joseph D; Whitney, Jonathan; Craig, Matthew T; Hobbs, Jean-Paul A; Rocha, Luiz A; Feldheim, Kevin A; Berumen, Michael L; Bowen, Brian W


    Closely related species can provide valuable insights into evolutionary processes through comparison of their ecology, geographic distribution and the history recorded in their genomes. In the Indo-Pacific, many reef fishes are divided into sister species that come into secondary contact at biogeographic borders, most prominently where Indian Ocean and Pacific Ocean faunas meet. It is unclear whether hybridization in this contact zone represents incomplete speciation, secondary contact, an evolutionary dead-end (for hybrids) or some combination of the above. To address these issues, we conducted comprehensive surveys of two widely-distributed surgeonfish species, Acanthurus leucosternon (N=141) and A. nigricans (N=412), with mtDNA cytochrome b sequences and ten microsatellite loci. These surgeonfishes are found primarily in the Indian and Pacific Oceans, respectively, but overlap at the Christmas and Cocos-Keeling Islands hybrid zone in the eastern Indian Ocean. We also sampled the two other Pacific members of this species complex, A. achilles (N=54) and A. japonicus (N=49), which are known to hybridize with A. nigricans where their ranges overlap. Our results indicate separation between the four species that range from the recent Pleistocene to late Pliocene (235,000-2.25million years ago). The Pacific A. achilles is the most divergent (and possibly ancestral) species with mtDNA dcorr≈0.04, whereas the other two Pacific species (A. japonicus and A. nigricans) are distinguishable only at a population or subspecies level (ΦST=0.6533, P<0.001). Little population structure was observed within species, with evidence of recent population expansion across all four geographic ranges. We detected sharing of mtDNA haplotypes between species and extensive hybridization based on microsatellites, consistent with later generation hybrids but also the effects of allele homoplasy. Despite extensive introgression, 98% of specimens had concordance between mtDNA lineage and

  5. Zebrafish Wnt9a,9b paralog comparisons suggest ancestral roles for Wnt9 in neural, oral-pharyngeal ectoderm and mesendoderm. (United States)

    Cox, A A; Jezewski, P A; Fang, P-K; Payne-Ferreira, T L


    The Wnts are a highly conserved family of secreted glycoproteins involved in cell-cell signaling and pattern formation during early embryonic development. Teasing out the role of individual Wnt molecules through development is challenging. Gene duplications are one of the most important mechanisms for generating evolutionary variations. The current consensus suggests that most anatomical variation is generated by divergence of regulatory control regions rather than by coding sequence divergence. Thus phylogenetic comparisons of divergent gene expression patterns are essential to understanding ancestral morphogenetic patterns from which subsequent anatomy diversified in modern lineages. We previously demonstrated strongest expression of zebrafish wnt9b within its heart tube, limb bud and ventral/anterior ectoderm during oral and pharyngeal arch patterning. Our goal is to compare and contrast zwnt9b to its closest paralog, zwnt9a. Sequenced, fulllength zebrafish wnt9a and wnt9b cDNA clones were used for phylogenetic analysis, which suggests their derivation from a common pre-vertebrate archeolog by gene duplication and divergence. Here we demonstrate that zwnt9a expression is found within unique (CNS, pronephric ducts, sensory organs) and overlapping (pectoral fin buds) expression domains relative to zwnt9b. Apparently, Wnt9 paralogs differentially parsed common ancestral expression domains during their subsequent rounds of gene duplication, divergence and loss in different vertebrate lineages. This expression data suggests ancestral roles for Wnt9s in early patterning of neural/oral-pharyngeal ectoderm and mesendoderm derivatives.

  6. Evolution of echinoderms may not have required modification of the ancestral deuterostome HOX gene cluster: first report of PG4 and PG5 Hox orthologues in echinoderms. (United States)

    Long, Suzanne; Martinez, Pedro; Chen, Wei-Chung; Thorndyke, Michael; Byrne, Maria


    Is the extreme derivation of the echinoderm body plan reflected in a derived echinoderm Hox genotype? Building on previous work, we exploited the sequence conservation of the homeobox to isolate putative orthologues of several Hox genes from two asteroid echinoderms. The 5-peptide motif (LPNTK) diagnostic of PG4 Hox genes was identified immediately downstream of one of the partial homeodomains from Patiriella exigua. This constitutes the first unequivocal report of a PG4 Hox gene orthologue from an echinoderm. Subsequent screenings identified genes of both PG4 and PG4/5 in Asterias rubens. Although in echinoids only a single gene (PG4/5) occupies these two contiguous cluster positions, we conclude that the ancestral echinoderm must have had the complete deuterostome suite of medial Hox genes, including orthologues of both PG4 and PG4/5 (=PG5). The reported absence of PG4 in the HOX cluster of echinoids is therefore a derived state, and the ancestral echinoderm probably had a HOX cluster not dissimilar to that of other deuterostomes. Modification of the ancestral deuterostome Hox genotype may not have been required for evolution of the highly derived echinoderm body plan.

  7. Springtime trans-Pacific transport of Asian pollutants characterized by the Western Pacific (WP) pattern (United States)

    Koo, Ja-Ho; Kim, Jaemin; Kim, Jhoon; Lee, Hanlim; Noh, Young Min; Lee, Yun Gon


    Springtime trans-Pacific transport of Asian air pollutants has been investigated in many ways to figure out its mechanism. Based on the Western Pacific (WP) pattern, one of climate variabilities in the Northern Hemisphere known to be associated with the pattern of atmospheric circulation over the North Pacific Ocean, in this study, we characterize the pattern of springtime trans-Pacific transport using long-term satellite measurements and reanalysis datasets. A positive WP pattern is characterized by intensification of the dipole structure between the northern Aleutian Low and the southern Pacific High over the North Pacific. The TOMS/OMI Aerosol Index (AI) and MOPITT CO show the enhancement of Asian pollutant transport across the Pacific during periods of positive WP pattern, particularly between 40 and 50°N. This enhancement is confirmed by high correlations of WP index with AI and CO between 40 and 50°N. To evaluate the influence of the WP pattern, we examine several cases of trans-Pacific transport reported in previous research. Interestingly, most trans-Pacific transport cases are associated with the positive WP pattern. During the period of negative WP pattern, reinforced cyclonic wave breaking is consistently found over the western North Pacific, which obstructs zonal advection across the North Pacific. However, some cases show the trans-Pacific transport of CO in the period of negative WP pattern, implying that the WP pattern is more influential on the transport of particles mostly emitted near ∼40°N. This study reveals that the WP pattern can be utilized to diagnose the strength of air pollutant transport from East Asia to North America.

  8. Heart Disease and Asians and Pacific Islanders (United States)

    ... Data > Minority Population Profiles > Asian American > Heart Disease Heart Disease and Asians and Pacific Islanders Overall, Asian American ... are less likely than white adults to have heart disease and they are less likely to die from ...

  9. PODs cruise - Pacific Orcinus Distrbution Survey (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Orcinus spp. occur in the Pacific Ocean throughout the West Coast of North America. Data concerning their precise locations and abundance are critical to...

  10. 1- HARPs of the Pacific Islands Region (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains information on acoustic recordings of cetaceans collected from areas within the Pacific Islands Region since 2006. In collaboration with...

  11. Eastern Pacific Ocean Purse-seine Fishery (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vessel logbook and landings data sets from U.S.A.-flagged purse-seine vessels fishing in the Eastern Pacific Ocean (EPO). These purse seiners...

  12. Pacific Islands Climate Change Virtual Library (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Virtual Library provides access to web based climate variability and climate change information and tools relevant to the Pacific Islands including case studies,...

  13. Asian Pacific Journal of Tropical Biomedicine

    Institute of Scientific and Technical Information of China (English)


    <正>APJTB Monthly Aims&Scope Asian Pacific Jounrnal of Tropical Biomedicine(APJTB)aims to set up and provide an international academic communication platform for physicians,medical scientists,allied health scientists and public health workers,especially those in the Asian Pacific region and worldwide on tropical biomedicine,infectious diseases and public health,and to meet the growing challenges

  14. Bryophyte floras of tropical Pacific islands


    Miller, Harvey A.; Whittier, Henry O.


    A review of the status of bryological research in each of the nations, states or governmental units of southern Melanesia, Micronesia and tropical Polynesia shows the imperfect state of knowledge about the Pacific tropical islands. Best known overall are Hawaii and Micronesia with Wallis and Futuna, the Marquesas and the high mountains of Fiji seeming to be the least known potentially species rich areas. Involvement of residents from Pacific islands in botanical study and preservation of ecos...

  15. Institutional balancing in the Asia-Pacific




    This study is about how the secondary (smaller) powers of the Asia-Pacific region balance the major powers – the US and China – through multilateral (regional) institutions in the international system. This paper explains the increasing importance of the Asia-Pacific region, where the major powers encounter and challenge each other, and examines the smaller powers of the region, which pursue balancing policies against the major powers through multilateral (regional) institutions. Therefore, t...

  16. Pacific Trade Deal Faces Tough Choices

    Institute of Scientific and Technical Information of China (English)

    Financial Times


    @@ The annual meeting of the Asia-Pacific Economic Cooperation (APEC) forum in Hawaii will have something more concrete to focus on than the usual bromides about extending free trade in the region. Barack Obama, the host, will use the occasion to laud progress in the "trans-Pacific partnership" (TPP), a nascent trade deal aiming to knit together a coalition including the US, Chile, Australia, Vietnam and Malaysia.

  17. The Future SSC Pacific Civil Service Workforce (United States)


    TECHNICAL REPORT 1971 August 2008 The Future SSC Pacific Civil Service Workforce P. Shigley G. Pennoyer J. Carreño Approved for... Shigley G. Pennoyer J. Carreño Approved for public release; distribution is unlimited. SSC San Diego San Diego, CA 92152-5001 SB...Prescribed by ANSI Std. Z39.18 08–2008 Final THE FUTURE SSC PACIFIC CIVIL SERVICE WORKFORCE P. Shigley G. Pennoyer J

  18. Pacific salmonines in the Great Lakes Basin (United States)

    Claramunt, Randall M.; Madenjian, Charles P.; Clapp, David; Taylor, William W.; Lynch, Abigail J.; Leonard, Nancy J.


    Pacific salmon (genus Oncorhynchus) are a valuable resource, both within their native range in the North Pacific rim and in the Great Lakes basin. Understanding their value from a biological and economic perspective in the Great Lakes, however, requires an understanding of changes in the ecosystem and of management actions that have been taken to promote system stability, integrity, and sustainable fisheries. Pacific salmonine introductions to the Great Lakes are comprised mainly of Chinook salmon, coho salmon, and steelhead and have accounted for 421, 177, and 247 million fish, respectively, stocked during 1966-2007. Stocking of Pacific salmonines has been effective in substantially reducing exotic prey fish abundances in several of the Great Lakes (e.g., lakes Michigan, Huron, and Ontario). The goal of our evaluation was to highlight differences in management strategies and perspectives across the basin, and to evaluate policies for Pacific salmonine management in the Great Lakes. Currently, a potential conflict exists between Pacific salmonine management and native fish rehabilitation goals because of the desire to sustain recreational fisheries and to develop self-sustaining populations of stocked Pacific salmonines in the Great Lakes. We provide evidence that suggests Pacific salmonines have not only become naturalized to the food webs of the Great Lakes, but that their populations (specifically Chinook salmon) may be fluctuating in concert with specific prey (i.e., alewives) whose populations are changing relative to environmental conditions and ecosystem disturbances. Remaining questions, however, are whether or not “natural” fluctuations in predator and prey provide enough “stability” in the Great Lakes food webs, and even more importantly, would a choice by managers to attempt to reduce the severity of predator-prey oscillations be antagonistic to native fish restoration efforts. We argue that, on each of the Great Lakes, managers are pursuing

  19. 1997 Pacific Northwest Loads and Resources Study.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.


    The 1997 White Book is presented in two documents: (1) this summary of Federal system and Pacific Northwest region loads and resources; and (2) a technical appendix detailing the loads and resources for each major Pacific Northwest generating utility. Data detailing Pacific Northwest non-utility generating (NUG) resources is also available upon request. This analysis updates the 1996 pacific Northwest Loads and Resources Study, published in December 1996. In this loads and resources study, resource availability is compared with a medium forecast of electricity consumption. This document analyzes the Pacific Northwest`s projected loads and available generating resources in two parts: (1) the loads and resources of the Federal system, for which BPA is the marketing agency; and (2) the larger Pacific Northwest regional power system which includes loads and resources in addition to the Federal system. This study presents the Federal system and regional analyses for the medium load forecast. This analysis projects the yearly average energy consumption and resource availability for Operating Years (OY) 1998--99 through 2007--08.

  20. Zonal displacement of western Pacific warm pool and zonal wind anomaly over the Pacific Ocean

    Institute of Scientific and Technical Information of China (English)


    The thermal condition anomaly of the western Pacific warm pool and its zonal displacement have very important influences on climate change in East Asia and even the whole world.However, the impact of the zonal wind anomaly over the Pacific Ocean on zonal displacement of the warm pool has not yet been analyzed based on long-term record. Therefore, it is important to study the zonal displacement of the warm pool and its response to the zonal wind anomaly over the equatorial Pacific Ocean. Based on the NCDC monthly averaged SST (sea surface temperature) data in 2°×2° grid in the Pacific Ocean from 1950 to 2000, and the NCEP/NCAR global monthly averaged 850 hPa zonal wind data from 1949 to 2000, the relationships between zonal displacements of the western Pacific warm pool and zonal wind anomalies over the tropical Pacific Ocean are analyzed in this paper. The results show that the zonal displacements are closely related to the zonal wind anomalies over the western, central and eastern equatorial Pacific Ocean. Composite analysis indicates that during ENSO events, the warm pool displacement was trigged by the zonal wind anomalies over the western equatorial Pacific Ocean in early stage and the process proceeded under the zonal wind anomalies over the central and eastern equatorial Pacific Ocean unless the wind direction changes. Therefore, in addition to the zonal wind anomaly over the western Pacific, the zonal wind anomalies over the central and eastern Pacific Ocean should be considered also in investigation the dynamical mechanisms of the zonal displacement of the warm pool.

  1. Mismatching Perspectives and Pacific Transculturality

    Directory of Open Access Journals (Sweden)

    Anne Holden Rønning


    Full Text Available Increased critical consciousness and awareness of interculturality in a global and glocal context at the beginning of the twenty-first century has increasingly used the concept of transculturation when discussing modernities. Politically transculturation can be used to describe processes of negotiation in contemporary society that lead to social awareness and solidarity, as well as ensuring the continuity of societies. The fusing of cultural forms leads to a mismatching of perspectives, hence some critics have preferred to use the terms translation and/or transliteracy to describe this concept. Transculturation is related to the “normal processes of artistic borrowing and influence, by which any culture makes part of its contribution to the conversation of mankind,” as Les Murray maintained, and “it engages multiple lines of difference simultaneously” with overlapping boundaries (Rogers 491. Referring to various authors and linking it to cultural appropriation and border crossings, this article examines how the narrative expression of Both Sides of the Moon, to cite the title of Alan Duff’s book, is a key feature of Pacific writing, in an area where centuries of migration from near and far have exposed different cultures to each other on social, political, linguistic and aesthetic levels. These ‘contact zones’, to use Mary Pratt’s words, provide the reader with constantly moving translated identities, cultural hybridity and a use of language that has a highly local significance in a global context.

  2. The Pacific sea surface temperature

    Energy Technology Data Exchange (ETDEWEB)

    Douglass, David H., E-mail: [Department of Physics and Astronomy, University of Rochester, Rochester, NY 14627-0171 (United States)


    The Pacific sea surface temperature data contains two components: N{sub L}, a signal that exhibits the familiar El Niño/La Niña phenomenon and N{sub H}, a signal of one-year period. Analysis reveals: (1) The existence of an annual solar forcing F{sub S}; (2) N{sub H} is phase locked directly to F{sub S} while N{sub L} is frequently phase locked to the 2nd or 3rd subharmonic of F{sub S}. At least ten distinct subharmonic time segments of N{sub L} since 1870 are found. The beginning or end dates of these segments have a near one-to-one correspondence with the abrupt climate changes previously reported. Limited predictability is possible. -- Highlights: ► El Niño/La Niña consists of 2 components phase-locked to annual solar cycle. ► The first component N{sub L} is the familiar El Niño/La Niña effect. ► The second N{sub H} component has a period of 1 cycle/year. ► N{sub L} can be phase-locked to 2nd or 3rd subharmonic of annual cycle. ► Ends of phase-locked segments correspond to abrupt previously reported climate changes.

  3. Renewable Energy Country Profiles. Pacific

    Energy Technology Data Exchange (ETDEWEB)



    The IRENA Renewable Energy Country Profiles take stock of the latest development of renewable energy in two regions where renewable energy can make a significant contribution to combat climate change and bring modern energy services to everyone: Africa and the Pacific. These two regions are presented separately in this volume and its sister publication. The country profiles combine elements of IRENA analysis with the latest information available from a vast array of sources in order to give a brief yet comprehensive and up-to-date picture of the situation of renewable energy that includes energy supply, electrical capacity, energy access, policies, targets, investment climate, projects and endowment in renewable energy resources. Because of the different timelines of these sources, data presented here refer to years between 2008 and 2012. Data availability also differs from country to country, which makes comparison with a wider regional group possible only for the year for which figures are available for all the members of the group; while this may not be the most recent year, the differences between countries, regions and the world remain striking. The current country profiles are just a starting point; they will be extended upon with new indicators to make them more informative, and maintained as a live product on the IRENA website as a key source of information on renewable energy.

  4. ¿Con o sin ancestros?: vigencia de lo ancestral en la Amazonía peruana

    Directory of Open Access Journals (Sweden)

    Thomas Mouriès


    Full Text Available La existencia o no de ancestros en la Amazonía indígena ha sido objeto de importantes debates. Sin embargo, los líderes de la región no dudan en llamar ‘ancestrales’ sus saberes, normas o territorios, en un sentido que, desde un punto de vista académico, puede parecer enigmático. «Ancestrales, pero… ¿con o sin ancestros?», preguntaría entonces, confuso, el antropólogo. En este artículo propongo aportar elementos de respuesta a esta pregunta a través del caso peruano. Primero analizo cómo los líderes indígenas amazónicos, conectándose al circuito del derecho internacional, adoptan la noción jurídica de ‘posesión ancestral’ del territorio para adaptarla al ámbito político. Este planteamiento rinde cuenta de la generalización y uniformización reciente del vocablo ‘ancestral’ pero deja pendiente el problema de su eventual articulación con las cosmologías indígenas que pretende reflejar. Por eso, en la segunda parte, intento sondear sobre la pertinencia de la categoría de ‘ancestro’ en la Amazonía indígena, recordando brevemente el debate académico para ir definiendo en qué medida esta categoría puede cobrar sentido. A partir del testimonio de un experimentado líder awajún, la tercera parte permite, entonces, volver más explícitos los diferentes sentidos y planos referenciales que despliega la referencia a lo ancestral, mostrando cómo los indígenas amazónicos no solo adoptan elementos conceptuales y discursivos externos, sino que al mismo tiempo los transforman a partir de sus propias singularidades cosmológicas y perspectivas políticas.

  5. ABO (histo) blood group phenotype development and human reproduction as they relate to ancestral IgM formation: A hypothesis. (United States)

    Arend, Peter


    The formation of a histo (blood) group) ABO phenotype and the exclusion of an autoreactive IgM or isoagglutinin activity arise apparently in identical glycosylation of complementary domains on cell surfaces and plasma proteins. The fundamental O-glycan emptiness of the circulating IgM, which during the neonatal amino acid sequencing of the variable regions is exerting germline-specific O-GalNAc glycan-reactive serine/threonine residues that in the plasma of the adult human blood group O individuals apparently remain associated with the open glycosidic sites on the ABOH convertible red cell surface, must raise suggestions on a transient expression of developmental glycans, which have been "lost" over the course of maturation. In fact, while the mammalian non-somatic, embryogenic stem cell (ESC)- germ cell (GC) transformation is characterized by a transient and genetically as-yet-undefined trans-species-functional O-GalNAc glycan expression, in the C57BL/10 mouse such expression was potentially identified in growth-dependent, blood group A-like GalNAc glycan-bearing, ovarian glycolipids complementary with the syngeneic anti-A reactive IgM, which does not appear in early ovariectomized animals. This non-somatically encoded, polyreactive, ancestral IgM molecule has not undergone clonal selection and does primarily not differentiate between self and non-self and might, due to amino acid hydroxyl groups, highly suggest substrate competition with subsequent O-glycosylations in ongoing ESC-GC transformations and affecting GC maturation. However, the membrane-bound somatic N/O-glycotransferases, which initiate, after formation of the zygote, the complex construction of the human ABO phenotypes in the trans cisternae of the Golgi apparatus, are associated and/or completed with soluble enzyme versions exerting identical specificities in plasma and likely competing vice versa by glycosylation of neonatal IgM amino acids, where they suggest to accomplish the clearance of anti

  6. Exploring the 'cultural' in cultural competencies in Pacific mental health. (United States)

    Samu, Kathleen Seataoai; Suaalii-Sauni, Tamasailau


    Cultural competency is about the ability of individuals and systems to respond respectfully and effectively to the cultural needs of peoples of all cultures. Its general attributes include knowledge, attitudes, skills and professional judgment. In Pacific mental health, 'the cultural' is generally understood to be ethnic culture. Accordingly, Pacific cultural competencies assume ethnic specific markers. In mental health Pacific cultural competencies has seen a blending of cultural and clinical beliefs and practices. This paper provides an overview of five key theme areas arising from Auckland-based ethnic-specific Pacific workshop data: language, family, tapu relationships, skills and organisation policy. Workshop participants comprised of Pacific mental health providers, Pacific consumers, family members of Pacific consumers and members of the Pacific community members. This paper purports that identifying the perceptions of different Pacific groups on ethnic-specific elements of cultural competencies are necessary to build and strengthen the capacity and capability of mental health services to provide culturally relevant services.

  7. The Features of Development in the Pacific Countries of the African, Caribbean and Pacific Group (United States)

    Cuenca Garcia, Eduardo; Rodriguez Martin, Jose Antonio; Navarro Pabsdorf, Margarita


    In this article we present a new proposal for the measurement of development, applied to the Pacific Countries of the African, Caribbean and Pacific Group (ACP), conditional on their insularity, and with privileged relations with the European Union. Our index has been constructed attending to the criteria defined in the Goals of the Millennium…

  8. 76 FR 68332 - International Fisheries; Pacific Tuna Fisheries; Fishing Restrictions in the Eastern Pacific Ocean (United States)


    .... (e.g., American Samoa) or foreign (e.g., Ecuador, Mexico, Colombia, Costa Rica) ports. Skipjack and...; Pacific Tuna Fisheries; Fishing Restrictions in the Eastern Pacific Ocean AGENCY: National Marine... Conservation 2011-2013 (C-11-01); the Resolution Prohibiting Fishing on Data Buoys (C-11-03); and...

  9. 77 FR 73969 - International Fisheries; Pacific Tuna Fisheries; Fishing Restrictions in the Eastern Pacific Ocean (United States)


    .... Current IATTC membership includes: Belize, Canada, China, Chinese Taipei (Taiwan), Colombia, Costa Rica...; Pacific Tuna Fisheries; Fishing Restrictions in the Eastern Pacific Ocean AGENCY: National Marine... on commercial retention of bluefin tuna by U.S. fishing vessels operating in the Eastern...

  10. Paleomagnetic constraints on Cenozoic deformation along the northwest margin of the Pacific-Australian plate boundary zone through New Zealand (United States)

    Turner, Gillian M.; Michalk, Daniel M.; Little, Timothy A.


    New Zealand straddles the boundary between the Australian and Pacific plates, a zone of oblique continental convergence and transform motion. The actively deforming region offers a unique opportunity to study the dynamics of deformation, including vertical-axis rotation of rigid blocks within a transcurrent plate boundary zone. We present and interpret paleomagnetic data from three new and three previously published sites from the NW part of the South Island (NW Nelson region), where sedimentary strata dated between 36 and 10 Ma overlie the crystalline Paleozoic basement assemblages of the Gondwana margin. Compared with reference directions from the Australian apparent polar wander path, none of the results provide evidence of post-Eocene vertical-axis rotation. This suggests that for the past 36 Myr NW Nelson has remained a strong, coherent block that has moved as a contiguous part of the Australian plate. This is in marked contrast to the strongly rotated nature of more outboard accreted terranes to the east. For example, the Hikurangi Margin in the North Island (NW of the Alpine Fault) and the Marlborough region in the NE of the South Island (SE of the Alpine Fault), have both undergone diverse clockwise rotations of up to 140° since the early Paleogene. The NW tip of the South Island seems to have acted as a rigid backstop relative to these more complex oroclinal deformations. We infer that, because of its relatively stiff bulk rheology, it has not been drawn into the distributed plate boundary rotational deformation associated with the New Zealand Orocline.

  11. Influenza vaccines: an Asia-Pacific perspective. (United States)

    Jennings, Lance C


    This article provides an overview of some aspects of seasonal, pre-pandemic and pandemic influenza vaccines and initiatives aimed to increase influenza vaccine use within the Asia-Pacific region. Expanding the use of influenza vaccines in the Asia-Pacific region faces many challenges. Despite the recent regional history for the emergence of novel viruses, SARS, the H5N1 and H7N9, and the generation of and global seeding of seasonal influenza viruses and initiatives by WHO and other organisations to expand influenza awareness, the use of seasonal influenza vaccines remains low. The improvement in current vaccine technologies with the licensing of quadrivalent, live-attenuated, cell culture-based, adjuvanted and the first recombinant influenza vaccine is an important step. The development of novel influenza vaccines able to provide improved protection and with improved manufacturing capacity is also advancing rapidly. However, of ongoing concern are seasonal influenza impact and the low use of seasonal influenza vaccines in the Asia-Pacific region. Improved influenza control strategies and their implementation in the region are needed. Initiatives by the World Health Organization (WHO), and specifically the Western Pacific Regional Office of WHO, are focusing on consistent vaccine policies and guidelines in countries in the region. The Asian-Pacific Alliance for the Control of Influenza (APACI) is contributing through the coordination of influenza advocacy initiates.

  12. The Pacific Island Health Care Project

    Directory of Open Access Journals (Sweden)

    Donald Ames Person


    Full Text Available Introduction/BackgroundUS Associated/Affiliated Pacific Islands (USAPI include 3 Freely Associated States: Marshall Islands, Federated States of Micronesia, Palau and 3 Territories: American Samoa, Guam, and Commonwealth of the Northern Mariana Islands. ObjectiveThe Pacific Island Health Care Project (PIHCP provides humanitarian medical referral/consultation/care to >500,000 indigenous people of these remote islands. Methods In the mid-1990s, we developed a simple store-and-forward program to link the USAPI with Tripler Army Medical Center (TAMC. This application allowed image attachment to email consultations. ResultsMore than 8000 Pacific Islanders have benefited from the program. 3000 Pacific Islanders prior to telemedicine (1990-1997 and since store-and-forward telemedicine (1997-present, the PIHCP has helped an additional 5000. Records post dynamically and are stored in an archival database. Conclusion The PIHCP is the longest running telemedicine program in the world delivering humanitarian medical care. It has bridged the Developing World of the remote Pacific islands with advanced medical and surgical care available at a major US military teaching hospital.(The opinions expressed here are those of the author and not that of the Army, Department of Defense, or the US Government.

  13. Asia-Pacific lube oil markets

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, N.


    An overview of the Asia-Pacific (AP) lubricating oils market, its special characteristics, and its role in the global economy are presented. In the 'boom and bust' years of 1997-1999, the Asia-Pacific market was even bigger then the US market. For the short-term, the scenario is surplus capacity and poor margins, but in the long term there is enormous potential for growth. How fuel demand and quality is related to engine type is discussed. The three basic grades of baseoils are described, and the Asia-Pacific lube demand and the Asia-Pacific lube oil supply are discussed. There are 15 diagrams giving data on: (i) finished lubes in world markets as a percentage of total; (ii) how lube demand follows GDP per capita in Asia; (iii) AP baseoil capacity relationships; (iv) AP baseoil disposition by end use; (v) AP changing shares of baseoil demand; (vi) AP finished lube demand by subregion; (vii) AP finished lube demand growth, indexed; (viii) AP baseoil capacity by region; Singapore baseoil vs. Dubai crude prices, 1992-99; (ix) Singapore baseoil vs. crude prices, 1992-99; (x) AP baseoil deficit moved to surplus; (xi) AP baseoil production; (xii) East Asia net percentage change in lube sales, 1997-1999. (xiii) Southeast Asia net percentage change in lube sales, 1997-1999; (xiv) South East Asia and Australia net percentage change in lube sales, 1997-1999 and (xv) Asia-Pacific major lube marketers.

  14. An ancestral miR-1304 allele present in Neanderthals regulates genes involved in enamel formation and could explain dental differences with modern humans. (United States)

    Lopez-Valenzuela, Maria; Ramírez, Oscar; Rosas, Antonio; García-Vargas, Samuel; de la Rasilla, Marco; Lalueza-Fox, Carles; Espinosa-Parrilla, Yolanda


    Genetic changes in regulatory elements are likely to result in phenotypic effects that might explain population-specific as well as species-specific traits. MicroRNAs (miRNAs) are posttranscriptional repressors involved in the control of almost every biological process. These small noncoding RNAs are present in various phylogenetic groups, and a large number of them remain highly conserved at the sequence level. MicroRNA-mediated regulation depends on perfect matching between the seven nucleotides of its seed region and the target sequence usually located at the 3' untranslated region of the regulated gene. Hence, even single changes in seed regions are predicted to be deleterious as they may affect miRNA target specificity. In accordance to this, purifying selection has strongly acted on these regions. Comparison between the genomes of present-day humans from various populations, Neanderthal, and other nonhuman primates showed an miRNA, miR-1304, that carries a polymorphism on its seed region. The ancestral allele is found in Neanderthal, nonhuman primates, at low frequency (~5%) in modern Asian populations and rarely in Africans. Using miRNA target site prediction algorithms, we found that the derived allele increases the number of putative target genes for the derived miRNA more than ten-fold, indicating an important functional evolution for miR-1304. Analysis of the predicted targets for derived miR-1304 indicates an association with behavior and nervous system development and function. Two of the predicted target genes for the ancestral miR-1304 allele are important genes for teeth formation, enamelin, and amelotin. MicroRNA overexpression experiments using a luciferase-based assay showed that the ancestral version of miR-1304 reduces the enamelin- and amelotin-associated reporter gene expression by 50%, whereas the derived miR-1304 does not have any effect. Deletion of the corresponding target sites for miR-1304 in these dental genes avoided their repression

  15. Personal and Social Transformation in the Health Area through Education: A Brief Journey from the Ancestral Indigenous Wisdom to the Modern Tyranny of Healthiness

    Directory of Open Access Journals (Sweden)

    Andrés de Muller


    Full Text Available This paper aims at claiming the ancestral wisdom of indigenous people in the health area. It analyzes how health has been commodified in the interest of large companies (particularly those related to the pharmaceutical industry to the detriment of a holistic definition of wellness through education. Furthermore, the concept of health as a right disagrees with such commodification or sale to the highest bidder, which prompts dehumanization of health services and public misinformation. The abundance of self-proclaimed gurus or healers who appeal to autosuggestion contributes both to confusion and to an unhealthy cult of healthiness.

  16. Latest Miocene-earliest Pliocene evolution of the ancestral Rio Grande at the Española-San Luis Basin boundary, northern New Mexico (United States)

    Daniel J. Koning,; Scott Aby,; Grauch, V. J.; Matthew J. Zimmerer,


    We use stratigraphic relations, paleoflow data, and 40Ar/39Ar dating to interpret net aggradation, punctuated by at least two minor incisional events, along part of the upper ancestral Rio Grande fluvial system between 5.5 and 4.5 Ma (in northern New Mexico). The studied fluvial deposits, which we informally call the Sandlin unit of the Santa Fe Group, overlie a structural high between the San Luis and Española Basins. The Sandlin unit was deposited by two merging, west- to southwest-flowing, ancestral Rio Grande tributaries respectively sourced in the central Taos Mountains and southern Taos Mountains-northeastern Picuris Mountains. The river confluence progressively shifted southwestward (downstream) with time, and the integrated river (ancestral Rio Grande) flowed southwards into the Española Basin to merge with the ancestral Rio Chama. Just prior to the end of the Miocene, this fluvial system was incised in the southern part of the study area (resulting in an approximately 4–7 km wide paleovalley), and had sufficient competency to transport cobbles and boulders. Sometime between emplacement of two basalt flows dated at 5.54± 0.38 Ma and 4.82±0.20 Ma (groundmass 40Ar/39Ar ages), this fluvial system deposited 10–12 m of sandier sediment (lower Sandlin subunit) preserved in the northern part of this paleovalley. The fluvial system widened between 4.82±0.20 and 4.50±0.07 Ma, depositing coarse sand and fine gravel up to 14 km north of the present-day Rio Grande. This 10–25 m-thick sediment package (upper Sandlin unit) buried earlier south- to southeast-trending paleovalleys (500–800 m wide) inferred from aeromagnetic data. Two brief incisional events are recognized. The first was caused by the 4.82±0.20 Ma basalt flow impounding south-flowing paleodrainages, and the second occurred shortly after emplacement of a 4.69±0.09 Ma basalt flow in the northern study area. Drivers responsible for Sandlin unit aggradation may include climate

  17. The parasite Ichthyophonus sp. in Pacific herring from the coastal NE Pacific (United States)

    Hershberger, Paul K.; Gregg, Jacob L.; Hart, Lucas M.; Moffitt, Steve; Brenner, Richard L.; Stick, K.; Coonradt, Eric; Otis, E. O.; Vollenweider, Johanna J.; Garver, Kyle A.; Lovy, Jan; Meyers, Tilden R.


    The protistan parasite Ichthyophonus occurred in populations of Pacific herring Clupea pallasii Valenciennes throughout coastal areas of the NE Pacific, ranging from Puget Sound, WA north to the Gulf of Alaska, AK. Infection prevalence in local Pacific herring stocks varied seasonally and annually, and a general pattern of increasing prevalence with host size and/or age persisted throughout the NE Pacific. An exception to this zoographic pattern occurred among a group of juvenile, age 1+ year Pacific herring from Cordova Harbor, AK in June 2010, which demonstrated an unusually high infection prevalence of 35%. Reasons for this anomaly were hypothesized to involve anthropogenic influences that resulted in locally elevated infection pressures. Interannual declines in infection prevalence from some populations (e.g. Lower Cook Inlet, AK; from 20–32% in 2007 to 0–3% during 2009–13) or from the largest size cohorts of other populations (e.g. Sitka Sound, AK; from 62.5% in 2007 to 19.6% in 2013) were likely a reflection of selective mortality among the infected cohorts. All available information for Ichthyophonus in the NE Pacific, including broad geographic range, low host specificity and presence in archived Pacific herring tissue samples dating to the 1980s, indicate a long-standing host–pathogen relationship.

  18. The Rise and Decline of Japanese Pacifism

    Directory of Open Access Journals (Sweden)

    Yuan Cai


    Full Text Available The Japanese pacifist constitution has been a symbol of Japan’s commitment to peace and more importantly its renunciation of wartime militarism. There has been strong support for its continuing existence amongst the Japanese populace despite persistent attempts by the Japanese government to amend it. However, the prevalent pacifist sentiment is showing signs of fading vitality in recent times. This article purports to examine the underlying forces that contributed to the development and the decline of Japanese pacifism. A host of domestic and international factors were responsible for the growth of pacifism and its subsequent decline, but only three important domestic factors will be examined in detail: the concept of victimhood in the development of pacifism and its implication for its continuing strength, the importance of peace education and the role played by the influential Japan’s Teachers’ Union on the formation of pacifist conscience and finally, the influence of leftist organisations on the organised peace movement.

  19. Pacific Albacore Troll and Pole-and-line Fisheries (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The North Pacific and South Pacific Albacore Troll and Pole-and-line Fisheries project contains landings, logbooks, and size composition data from U.S.A. troll and...

  20. 33 CFR 3.04-3 - Pacific Area. (United States)


    ....04-3 Pacific Area. (a) The Area Office is in Alameda, CA. (b) The Pacific Area is comprised of the.... longitude to the North American land mass; thence along the west coast of the North, Central, and...

  1. Chronic Liver Disease and Native Hawaiian/Pacific Islanders (United States)

    ... Hawaiian/Other Pacific Islander > Chronic Liver Disease Chronic Liver Disease and Native Hawaiian/Pacific Islander Native Hawaiian/ ... times more likely to be diagnosed with chronic liver disease in 2006. American Samoans were 8 times ...

  2. AFSC/REFM: Pacific cod Localized Depletion Study (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Localized Depletion study for Pacific cod 2001-2005. Study was conducted using cod pot gear to measure localized abundance of Pacific cod inside and...

  3. Asia Pacific Mangrove Information Network (APMIN): A conceptual model

    Digital Repository Service at National Institute of Oceanography (India)

    Chavan, V.S.; Jagtap, T.G.; Untawale, A.G.

    Asia Pacific Mangrove Information Network (APMIN), its structure and scope, is discussed in this paper. Establishment of National Mangrove Information Centers (NMIC) in 20 Asia-Pacific countries, would contribute towards development of databases...

  4. Magmatic evolution in the N-Gondwana margin related to the opening of the Rheic Ocean—evidence from the Upper Parautochthon of the Galicia-Trás-os-Montes Zone and from the Central Iberian Zone (NW Iberian Massif) (United States)

    Dias da Silva, Ícaro; Díez Fernández, Rubén; Díez-Montes, Alejandro; González Clavijo, Emilio; Foster, David A.


    LA-MC-ICP-MS U-Pb zircon ages and whole-rock geochemical data obtained from volcanic rocks erupted in the northern margin of Gondwana provide new insights on the polyphase magmatic evolution of the NW Iberian domain during the establishment of passive margin conditions in Lower Paleozoic times. The U-Pb data show crystallization ages of ca. 455 Ma for two calc-alkaline rhyolites sampled in the Upper Parautochthon of the eastern Galicia—Trás-os-Montes Zone (GTMZ) and for an intraplate basalt intruded into Middle Ordovician slates of the autochthonous series of the Central Iberian Zone (CIZ). Together with previous data, the ages obtained reveal a periodic magmatic activity across the northern Gondwana margin during the Lower Paleozoic, which is comparable to that observed in NE Iberia and in other massifs of the Mediterranean realm. Both geochronological and geochemical data reinforce paleontological and stratigraphic evidences for paleogeographic proximity between these domains and contribute to the recognition of extensional-related magmatism along the northern margin of Central Gondwana associated with the opening of the Rheic Ocean.

  5. Requiem for an eastern Pacific seagrass bed. (United States)

    Cortés, J


    Few papers concerning seagrasses of the eastern Pacific have been published. This paper presents the first ecological data on the seagrass, Ruppia maritima, from a non-lagoonal setting in the eastern Pacific. A 5000 m2 patch formed by R. maritima, at Playa Iguanita, Bahía Culebra, Pacific coast of Costa Rica was studied. Plant density and leaf length of R. maritima were determined along two transects on different dates. Above and below ground biomass were calculated along one transect. Plant density ranged from 1590 to 8630 individuals m(-2) along the two transects, with means of 5990 +/- 1636 and 6100 +/- 1876 plants m(-2) for transect 1 and 2, respectively. Longest leaf length per plant varied between 0.5 and 23.0 cm. Leaf biomass (LB) ranged from 10 to 97 gm(-2), and root-rhizome biomass (RB) from 31 to 411 gm(-2), resulting in RB:LB ratios of 3.07 to 15.27. Total biomass at Bahía Culebra was lower than at tropical lagoons on the Pacific coast of Mexico, but higher than in the Gulf of Mexico. The below ground: above ground biomass ratio was much higher at Bahía Culebra than at other sites on the Pacific coast of Mexico and the Gulf of Mexico. Another seagrass present at Bahía Culebra was Halophila baillonii, with low densities on the deepest section of the patch. At least 44 invertebrate species associated with the seagrass bed have also been identified. The patch at Playa Iguanita and other sites within Bahía Culebra, as well as their associated organisms, disappeared after a severe storm in June 1996. No seagrasses have been found in the area or in any other location on the Pacific coast of Costa Rica since then.

  6. Out of the Pacific and back again: the matrilineal history of Pacific killer whale ecotypes

    DEFF Research Database (Denmark)

    Foote, Andrew David; Morin, PA; JW, Durban;


    Killer whales (Orcinus orca) are the most widely distributed marine mammals and have radiated to occupy a range of ecological niches. Disparate sympatric types are found in the North Atlantic, Antarctic and North Pacific oceans, however, little is known about the underlying mechanisms driving...... reconstructions and a clinal decrease in diversity suggest a North Pacific to North Atlantic founding event, and the later return of killer whales to the North Pacific. Therefore, ecological divergence could have occurred during the allopatric phase through drift or selection and/or may have either commenced...

  7. Natural phosphorus sources for the Pacific Northwest (United States)

    Johnson, Hank


    Phosphorus is a naturally occurring element found in all rocks; the amount varies by the type of rock. The amount of phosphorus in sediments is expected to be correlated with the amount of phosphorus in the parent rocks. Streambed sediment collected by the National Uranium Resource Evaluation (NURE) Program were used to estimate the variation of phosphorus across the Pacific Northwest. This file provides an estimate of the mean concentration of phosphorus in soils for each incremental catchment of the USGS Pacific Northwest SPARROW model.

  8. Tropical cyclone statistics in the Northeastern Pacific


    Romero Vadillo, E; Zaitsev, Oleg; Morales Pérez., R


    The principal area of tropical cyclogenesis in the tropical eastern Pacific Ocean is offshore in the Gulf of Tehuantepec, between 8 and 15° N, and most of these cyclones move towards the west and northwest during their initial phase. Historical analysis of tropical cyclone data in the Northeastern (NE) Pacific over the last 38 years (from 1966 to 2004) shows a mean of 16.3 tropical cyclones per year, consisting of 8.8 hurricanes and 7.4 tropical storms. The analysis shows great geographical v...

  9. CRED 20 m Gridded bathymetry of Johnston Atoll, Pacific Remote Island Areas, Central Pacific (Arc ASCII Format) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded bathymetry (20 m cell size) of the shelf and slope environments of Johnston Atoll, Pacific Remote Island Areas, Central Pacific. Almost complete bottom...

  10. CRED 5 m Gridded bathymetry of Baker Island, Pacific Remote Island Areas, Central Pacific (Arc ASCII Format) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded (5 m cell size) bathymetry of the shelf and slope environments of Baker Island, Pacific Remote Isand Areas, Central Pacific. Almost complete bottom coverage...

  11. CRED 40 m Gridded bathymetry of Baker Island, Pacific Remote Island Areas, Central Pacific (Arc ASCII Format) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded (40 m cell size) bathymetry of the shelf and slope environments of Baker Island, Pacific Remote Island Areas, Central Pacific. Almost complete bottom...

  12. CRED 40 m Gridded bathymetry of Howland Island, Pacific Remote Island Areas, Central Pacific (NetCDF Format) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded (40 m cell size) bathymetry of the shelf and slope environments of Howland Island, Pacific Remote Island Areas, Central Pacific. Almost complete bottom...

  13. CRED Reson 8101 multibeam backscatter data of Johnston Island, Pacific Remote Island Areas, Central Pacific in netCDF format (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of the lagoon, shelf, and slope environments of Palmyra Atoll, Pacific Island Areas, Central Pacific....

  14. CRED 5 m Gridded bathymetry of Johnston Atoll, Pacific Remote Island Areas, Central Pacific (NetCDF Format) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded bathymetry (5 m cell size) of the shelf and slope environments of Johnston Atoll, Pacific Remote Island Areas, Central Pacific. Almost complete bottom...

  15. CRED 5 m Gridded bathymetry of Kingman Reef, Pacific Remote Island Areas, Central Pacific (Arc ASCII Format) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded (5 m cell size) bathymetry of the lagoon, shelf and slope environments of Kingman Reef, Pacific Remote Island Areas, Central Pacific. Almost complete bottom...

  16. CRED 5 m Gridded bathymetry of Baker Island, Pacific Remote Island Areas, Central Pacific (NetCDF Format) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded (5 m cell size) bathymetry of the shelf and slope environments of Baker Island, Pacific Remote Island Areas, Central Pacific. Almost complete bottom coverage...

  17. CRED Reson 8101 multibeam backscatter data of Howland Island, Pacific Remote Island Areas, Central Pacific in GeoTIFF format (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of the shelf and slope environments of Howland Atoll, Pacific Island Areas, Central Pacific. These...

  18. CRED 40 m Gridded bathymetry of Baker Island, Pacific Remote Island Areas, Central Pacific (NetCDF Format) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded (40 m cell size) bathymetry of the shelf and slope environments of Baker Island, Pacific Remote Island Areas, Central Pacific. Almost complete bottom...

  19. CRED Reson 8101 multibeam backscatter data of Johnston Island, Pacific Remote Island Areas, Central Pacific in GeoTIFF format (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of the lagoon, shelf, and slope environments of Palmyra Atoll, Pacific Island Areas, Central Pacific....

  20. 76 FR 20959 - Pacific Fishery Management Council; Public Meeting (United States)


    ... Pacific mackerel stock assessment for 2011, in order to inform fisheries management decisions for the 2011... National Oceanic and Atmospheric Administration RIN 0648-XA366 Pacific Fishery Management Council; Public... (NOAA), Commerce. ACTION: Notice of a public meeting. SUMMARY: The Pacific Fishery Management...


    Salmon are categorized biologically into two groups: Pacific salmon or Atlantic salmon. All seven species of Pacific salmon on both sides of the North Pacific Ocean have declined substantially from historic levels, but large runs still occur in northern British Columbia, Yukon,...

  2. 76 FR 24465 - Pacific Gas and Electric Company (United States)


    ... Energy Regulatory Commission Pacific Gas and Electric Company Notice of Application Tendered for Filing....: 2310-193. c. Date Filed: April 12, 2011. d. Applicant: Pacific Gas and Electric Company. e. Name of... Contact: Steve Peirano, Relicensing Project Manager, Pacific Gas and Electric Company, P.O. Box...

  3. Response of Juvenile Pacific Lamprey to Turbine Passage

    Energy Technology Data Exchange (ETDEWEB)

    Dauble, D.


    To help determine the Pacific lamprey’s ability to survive turbine passage, Pacific Northwest National Laboratory scientists conducted laboratory tests designed to simulate a fish’s passage through the turbine environment. Juvenile Pacific lamprey were subjected to two of three aspects of passage: pressure drop and shear stress. The third aspect, blade strike, was not tested.

  4. Demineralization of Gondwana coal with Pseudomonas mendocina strain B6-1: a case study of coal from Gopinathpur top and bottom seams of Mugma mine, Dhanbad, Jharkhand (India)

    Institute of Scientific and Technical Information of China (English)

    Prakash K.Singh; Asha Lata Singh; Mahendra P.Singh; A.S.Naik; Dharmshila Singh; Spardha Rai; Aniruddha Kumar


    In the present investigation an attempt has been made to demineralize the Gondwana coal of Gopinathpur top and bottom seams of Mugma mine,Raniganj coalfield,Dhanbad with the help of Pseudomonas mendocina strain B6-1.The change in the amount of ash yield and decrease in the concentration of selected minor elements like Na,K,Mn and Ca and environmentally sensitive selected trace elements such as Cd,Pb,Se,Ni,Mn,and Zn have been studied as a function of time of bacterial treatment as well as with variation in the bacterial biomass.After 28 days of bacterial treatment there was variable amount of decrease observed in ash yield as well as in the concentration of minor and trace elements.The removal of the elements was further enhanced with the increase in the bacterial biomass from 10 to 25 mg/mL.Due to over exploitation of superior grade coals in the country,the remaining coal resources,available for current use,are inferior in grade and contain high level of impurities and there is ample scope of bio-beneficiation of these coals using bacterial biomass.

  5. Improved Moscovian part of the Gondwana APWP for paleocontinental reconstructions, obtained from a first paleomagnetic pole, age-constrained by a fold test, from In Ezzane area in the Murzuq basin (Algeria, stable Africa) (United States)

    Amenna, M.; Derder, M. E. M.; Henry, B.; Bayou, B.; Maouche, S.; Bouabdallah, H.; Ouabadi, A.; Ayache, M.; Beddiaf, M.


    To improve paleocontinental reconstructions, paleomagnetic reference curves (Apparent Polar Wander Path: APWP) feature for large continents have to be continuously refined by adding up new high-quality data. For stable Africa, the Moscovian period was favorable for such aim, with well-dated and widespread geological formations. A new study has been conducted in the Upper “Dembaba” geological formation of Lower Moscovian age outcropping in the western part of the “Murzuq” basin (Saharan platform). Well-defined ChRMs, combined with remagnetization circles data, both constrained in age by a positive fold test, yield a new significant paleomagnetic pole (λ = 25.2°S, ϕ = 59.9°E, K = 55, A95 = 5.4°). When joined with previous African data of the same age, it gives an improved reference pole for Africa (λ = 28.9°S, ϕ = 54.5°E, K = 106, A95 = 3.6°). The Mean Moscovian paleomagnetic pole determined from an updated Gondwana Paleozoic APWP (λ = 29.4°S, ϕ = 51.5°E, K = 11, A95 = 1.8°), associated with the corresponding Laurussia pole (Domeier et al., 2012), yields a more constrained paleocontinental reconstruction for 310 Ma.

  6. Estimating ancestral distributions of lineages with uncertain sister groups: a statistical approach to Dispersal-Vicariance Analysis and a case using Aesculus L. (Sapindaceae) including fossils

    Institute of Scientific and Technical Information of China (English)

    A.J. HARRIS; Qiu-Yun (Jenny) XIANG


    We propose a simple statistical approach for using Dispersal-Vicariance Analysis (DIVA) software to infer biogeographic histories without fully bifurcating trees. In this approach, ancestral ranges are first optimized for a sample of Bayesian trees. The probability P of an ancestral range r at a node is then calculated as P(rY)= Σnt=1 F(rY)tPt where Y is a node, and F(rY) is the frequency of range r among all the optimal solutions resulting from DIVA optimization at node Y, t is one of n topologies optimized, and Pt is the probability of topology t. Node Y is a hypothesized ancestor shared by a specific crown lineage and the sister of that lineage "x", where x may vary due to phylogenetic uncertainty (polytomies and nodes with posterior probability <100%). Using this method, the ancestral distribution at Y can be estimated to provide inference of the geographic origins of the specific crown group of interest. This approach takes into account phylogenetic uncertainty as well as uncertainty from DIVA optimization. It is an extension of the previously described method called Bayes-DIVA, which pairs Bayesian phylogenetic analysis with biogeographic analysis using DIVA. Further, we show that the probability P of an ancestral range at Y calculated using this method does not equate to pp* F(rY) on the Bayesian consensus tree when both variables are < 100%, where pp is the posterior probability and F(rY) is the frequency of range r for the node containing the specific crown group. We tested our DIVA-Bayes approach using Aesculus L., which has major lineages unresolved as a polytomy. We inferred the most probable geographic origins of the five traditional sections of Aesculus and ofAesculus californica Nutt. and examined range subdivisions at parental nodes of these lineages.Additionally, we used the DIVA-Bayes data from Aesculus to quantify the effects on biogeographic inference of including two wildcard fossil taxa in phylogenetic analysis. Our analysis resolved the

  7. 76 FR 28422 - Fisheries of the Pacific Region; Western Pacific Region (United States)


    ... Administration (NOAA), Commerce. ACTION: Notification of determination of overfishing or an overfished condition... Fishery Management Council (Western Pacific Council), is subject to overfishing. NMFS notifies the appropriate fishery management council (Council) whenever it determines that; overfishing is occurring,...

  8. The Third Pacific Basin Biofuels Workshop: Proceedings (United States)

    Among the many compelling reasons for the development of biofuels on remote Pacific islands, several of the most important include: (1) a lack of indigenous fossil fuels necessitates their import at great economic loss to local island economics, (2) ideal conditions for plant growth exist on many Pacific islands to produce yields of biomass feedstocks, (3) gaseous and liquid fuels such as methane, methanol and ethanol manufactured locally from biomass feedstocks are the most viable alternatives to gasoline and diesel fuels for transportation, and (4) the combustion of biofuels is cleaner than burning petroleum products and contributes no net atmospheric CO2 to aggravate the greenhouse effect and the subsequent threat of sea level rise to low islands. Dr. Vic Phillips, HNEI Program Manager of the Hawaii Integrated Biofuels Research Program welcomed 60 participants to the Third Pacific Basin Biofuels Workshop at the Sheraton Makaha Hotel, Waianae, Oahu, on March 27 and 28, 1989. The objectives of the workshop were to update progress since the Second Pacific Basin Biofuels Workshop in April 1987 and to develop a plan for action for biofuels R and D, technology transfer, and commercialization now (immediate attention), in the near-term (less than two years), in the mid-term (three to five years), and in the long-term (more than six years). An emerging theme of the workshop was how the production, conversion, and utilization of biofuels can help increase environmental and economic security locally and globally. Individual papers are processed separately for the data base.

  9. African and Pacific Literature: A Comparative Study. (United States)

    Martin, Kristine L.

    Literary writing in Africa and the Pacific addresses themes that reflect colonial experience and the struggles of newly independent nations to cope with change and conflicts between traditional and modern existence. The novels of Chinua Achebe of Nigeria and Ngugi Wa Thiong'o of Kenya illustrate many dominant themes of African literature. Achebe…

  10. A Beautiful Story Across the Pacific

    Institute of Scientific and Technical Information of China (English)



    China and the U.S. are separated geographically by the vast Pacific while there is difference between the two countriesI historical backgrounds, cultural traditions, political systems and theories, as well as the stages of economic development. They therefore have the very need to promote the exchanges and

  11. Asian Pacific Journal of Tropical Biomedicine

    Institute of Scientific and Technical Information of China (English)

    Alexandra Bagley; Usman H Malabu


    Two-third of the world’s population lives in the Asia Pacific region where prevalence of diabetes has reached epidemic proportion. With China and India being the most populous nations on the globe, it is believed that over 150 million diabetes reside in the region with more than 95% being of type 2 diabetes mellitus (T2DM). Furthermore, other Pacific islands in the region have high rates of T2DM including Tonga, Fiji, French Polynesia, and Nauru. The latter has the highest prevalence of T2DM per population in the world. Over the past two decades, in Australia and New Zealand, the prevalence of T2DM has more than doubled, mainly amongst the Aboriginal and Torres Strait Islander and Maori peoples respectively. With the increasing prevalence of diabetes in the Asia Pacific region coupled with the limited number of resources, use of a reliable and effective mode of diagnosis for T2DM is warranted. Yet to date, only New Zealand has adopted the American Diabetes Association recommendation of using hemoglobin A1C in the diagnosis of the disease. The aim of this review is to discuss the clinical usefulness of hemoglobin A1C and highlight its diagnostic role in the Asia Pacific region where T2DM is increasingly encountered.


    Throughout the Pacific Northwest, since 1850, all wild salmon runs have declined and some have disappeared. Billions of dollars have been spent in a so-far failed attempt to reverse the long-term decline. Each year, hundreds of millions of dollars continue to be spent in variou...

  13. Loading up Asia-Pacific style

    Energy Technology Data Exchange (ETDEWEB)

    Keith, A.; Johnson, R. [PT Connell Wagner, Jakarta (Indonesia)


    Coal shiploading ports dot the coastlines of many parts of the Asia Pacific region, being the nodes where inland transportation and sea transportation meet. The article is based on a paper entitled 'Overview of Asia's shiploading ports and transhipment operation for coal' presented at Coaltrans Asia in June 2003. 1 fig., 4 photos.

  14. Pulse crop diseases in the Pacific Northwest (United States)

    The United Nations declared that 2016 is the International Year of Pulses (IYP). This UN declaration of IYP will certainly increase awareness of pulses and likely position pulses as a primary source of protein and other essential nutrients for human diets. The US Pacific Northwest region (Idaho, Or...

  15. Establishing bioinformatics research in the Asia Pacific

    Directory of Open Access Journals (Sweden)

    Tammi Martti


    Full Text Available Abstract In 1998, the Asia Pacific Bioinformatics Network (APBioNet, Asia's oldest bioinformatics organisation was set up to champion the advancement of bioinformatics in the Asia Pacific. By 2002, APBioNet was able to gain sufficient critical mass to initiate the first International Conference on Bioinformatics (InCoB bringing together scientists working in the field of bioinformatics in the region. This year, the InCoB2006 Conference was organized as the 5th annual conference of the Asia-Pacific Bioinformatics Network, on Dec. 18–20, 2006 in New Delhi, India, following a series of successful events in Bangkok (Thailand, Penang (Malaysia, Auckland (New Zealand and Busan (South Korea. This Introduction provides a brief overview of the peer-reviewed manuscripts accepted for publication in this Supplement. It exemplifies a typical snapshot of the growing research excellence in bioinformatics of the region as we embark on a trajectory of establishing a solid bioinformatics research culture in the Asia Pacific that is able to contribute fully to the global bioinformatics community.

  16. Changing housing policy landscapes in Asia Pacific

    NARCIS (Netherlands)

    R. Ronald; R.L.H. Chiu


    The Asia Pacific region, and in particular East Asia, underwent rapid urbanisation and industrialisation in the latter decades of the twentieth century. Central to this transformation was intensive public and private investment in the housing sector. Although housing was largely commodified, public

  17. Pacific ethnic groups and frequent hospital presentation: A fair target? (United States)

    Irvine, Zoe


    In New Zealand, Pacific health figures are traditionally presented for all Pacific ethnic groups combined. Use of EDs and urgent care clinics is high compared with Maori and non-Maori, non-Pacific (nMnP) use. By controlling for proximity to the hospital and socioeconomic status, we demonstrate greater variation between Pacific ethnic groups than between Pacific and nMnP, or between Maori and nMnP groups. We discuss the significance of subpopulation variation in use of urgent care services.


    Institute of Scientific and Technical Information of China (English)

    JinShuanggen; ZhuWenyao


    The circum-Pacific tectonic system that contains of convergent, divergent and transform boundaries, is the most active region of volcanoes and earthquakes in the world, and involves many important theoretical questions in geosciences. The relative motion and deformation of Pacific plate is still an active subject of research. In this note, we analyze the deformation of Pacific plate and obtain reliable results of the relative motion rates at the circum-Pacific boundaries based on space geodetic data, which reveals the present-day motion characteristics of Pacific plate.

  19. Pacific Lamprey Research and Restoration : Annual Report 1997.

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, Aaron D.; Hatch, Douglas R.; Close, David A.


    The once abundant stocks of Pacific lamprey (Lampetra tridentata) above Bonneville Dam are currently depressed (Close et al. 1995). It is likely that many of the same factors that led to the decline of wild stocks of Columbia River Pacific salmon and steelhead have impacted Pacific lamprey populations as well. The Pacific Lamprey Research and Restoration Project, funded by Bonneville Power Administration, is a cooperative effort between the Confederated Tribes of the Umatilla Indian Reservation, the Columbia River Inter-Tribal Fish Commission, and Oregon State University with the goal to increase Pacific lamprey stocks above Bonneville Dam.

  20. Indo-Pacific: Origin and Multinational Strategic Game-play

    Institute of Scientific and Technical Information of China (English)

    WU; Zhaoli


    In recent years, the United States, Australia and India have initiated the Indo-Pacific concept,which is not a simple result of the Indian Ocean plus the Pacific Ocean, but a geo-economic and geo-political development of the two regions.Indo-Pacific reflects the shift of the global economic gravity and strategic center,and the China factor is obvious in this process.The extending Chinese strategic interests are beyond the traditional Asia-Pacific region, but China as a typical Indo-Pacific country should be cautious about the "selective exclusion"and "targeted promotion"

  1. Biophysical Feedbacks in the Tropical Pacific. (United States)

    Marzeion, Ben; Timmermann, Axel; Murtugudde, Ragu; Jin, Fei-Fei


    This study explores the influence of phytoplankton on the tropical Pacific heat budget. A hybrid coupled model for the tropical Pacific that is based on a primitive equation reduced-gravity multilayer ocean model, a dynamic ocean mixed layer, an atmospheric mixed layer, and a statistical atmosphere is used. The statistical atmosphere relates deviations of the sea surface temperature from its mean to wind stress anomalies and allows for the rectification of the annual cycle and the El Niño-Southern Oscillation (ENSO) phenomenon through the positive Bjerknes feedback. Furthermore, a nine-component ecosystem model is coupled to the physical variables of the ocean. The simulated chlorophyll concentrations can feed back onto the ocean heat budget by their optical properties, which modify solar light absorption in the surface layers. It is shown that both the surface layer concentration as well as the vertical profile of chlorophyll have a significant effect on the simulated mean state, the tropical annual cycle, and ENSO. This study supports a previously suggested hypothesis (Timmermann and Jin) that predicts an influence of phytoplankton concentration of the tropical Pacific climate mean state and its variability. The bioclimate feedback diagnosed here works as follows: Maxima in the subsurface chlorophyll concentrations lead to an enhanced subsurface warming due to the absorption of photosynthetically available shortwave radiation. This warming triggers a deepening of the mixed layer in the eastern equatorial Pacific and eventually a reduction of the surface ocean currents (Murtugudde et al.). The weakened south-equatorial current generates an eastern Pacific surface warming, which is strongly enhanced by the Bjerknes feedback. Because of the deepening of the mixed layer, the strength of the simulated annual cycle is also diminished. This in turn leads to an increase in ENSO variability.

  2. The chromosome complement of Acomys spp. (Rodentia, Muridae) from Oursi, Burkina Faso--the ancestral karyotype of the cahirinus-dimidiatus group? (United States)

    Volobouev, V; Gautun, J C; Sicard, B; Tranier, M


    We present here data on chromosome banding analysis (R- and C-bands) of Acomys sp. (Rodentia, Muridae) from Oursi, Burkina Faso, characterized by 2n = FN = 68 and comparison of its banding patterns with those of Acomys dimidiatus from Saudi Arabia (2n = 38, FN = 70), studied previously. The study revealed complete homology between acrocentric chromosomes of Acomys sp. and chromosome arms of 16 pairs of metacentric and two pairs of acrocentric chromosomes of A. dimidiatus. In addition to monobrachial homology, one tandem translocation accompanied by a centromeric shift was identified in the karyotype of the latter species. The data obtained show that karyotypes of all the species of the Acomys cahirinus-dimidiatus group studied previously may be derived from that of Acomys sp. from Oursl by means of numerous non-homologous Rb translocations and 1-2 tandem transiocations, and thus its karyotype may be considered as ancestral for the cahirinus-dimidiatus group.

  3. Bayesian phylogeography of influenza A/H3N2 for the 2014-15 season in the United States using three frameworks of ancestral state reconstruction (United States)

    Suchard, Marc A.


    Ancestral state reconstructions in Bayesian phylogeography of virus pandemics have been improved by utilizing a Bayesian stochastic search variable selection (BSSVS) framework. Recently, this framework has been extended to model the transition rate matrix between discrete states as a generalized linear model (GLM) of genetic, geographic, demographic, and environmental predictors of interest to the virus and incorporating BSSVS to estimate the posterior inclusion probabilities of each predictor. Although the latter appears to enhance the biological validity of ancestral state reconstruction, there has yet to be a comparison of phylogenies created by the two methods. In this paper, we compare these two methods, while also using a primitive method without BSSVS, and highlight the differences in phylogenies created by each. We test six coalescent priors and six random sequence samples of H3N2 influenza during the 2014–15 flu season in the U.S. We show that the GLMs yield significantly greater root state posterior probabilities than the two alternative methods under five of the six priors, and significantly greater Kullback-Leibler divergence values than the two alternative methods under all priors. Furthermore, the GLMs strongly implicate temperature and precipitation as driving forces of this flu season and nearly unanimously identified a single root state, which exhibits the most tropical climate during a typical flu season in the U.S. The GLM, however, appears to be highly susceptible to sampling bias compared with the other methods, which casts doubt on whether its reconstructions should be favored over those created by alternate methods. We report that a BSSVS approach with a Poisson prior demonstrates less bias toward sample size under certain conditions than the GLMs or primitive models, and believe that the connection between reconstruction method and sampling bias warrants further investigation. PMID:28170397

  4. Evolution of bacterial-like phosphoprotein phosphatases in photosynthetic eukaryotes features ancestral mitochondrial or archaeal origin and possible lateral gene transfer. (United States)

    Uhrig, R Glen; Kerk, David; Moorhead, Greg B


    Protein phosphorylation is a reversible regulatory process catalyzed by the opposing reactions of protein kinases and phosphatases, which are central to the proper functioning of the cell. Dysfunction of members in either the protein kinase or phosphatase family can have wide-ranging deleterious effects in both metazoans and plants alike. Previously, three bacterial-like phosphoprotein phosphatase classes were uncovered in eukaryotes and named according to the bacterial sequences with which they have the greatest similarity: Shewanella-like (SLP), Rhizobiales-like (RLPH), and ApaH-like (ALPH) phosphatases. Utilizing the wealth of data resulting from recently sequenced complete eukaryotic genomes, we conducted database searching by hidden Markov models, multiple sequence alignment, and phylogenetic tree inference with Bayesian and maximum likelihood methods to elucidate the pattern of evolution of eukaryotic bacterial-like phosphoprotein phosphatase sequences, which are predominantly distributed in photosynthetic eukaryotes. We uncovered a pattern of ancestral mitochondrial (SLP and RLPH) or archaeal (ALPH) gene entry into eukaryotes, supplemented by possible instances of lateral gene transfer between bacteria and eukaryotes. In addition to the previously known green algal and plant SLP1 and SLP2 protein forms, a more ancestral third form (SLP3) was found in green algae. Data from in silico subcellular localization predictions revealed class-specific differences in plants likely to result in distinct functions, and for SLP sequences, distinctive and possibly functionally significant differences between plants and nonphotosynthetic eukaryotes. Conserved carboxyl-terminal sequence motifs with class-specific patterns of residue substitutions, most prominent in photosynthetic organisms, raise the possibility of complex interactions with regulatory proteins.

  5. The impact of ancestral heath management on soils and landscapes. A reconstruction based on paleoecological analyses of soil records in the middle and southeast Netherlands. (United States)

    van Mourik, Jan; Doorenbosch, Marieke


    The evolution of heath lands during the Holocene has been registered in various soil records . Paleoecological analyses of these records enable to reconstruct the changing economic and cultural management of heaths and the consequences for landscape and soils. Heaths are characteristic components of cultural landscape mosaics on sandy soils in the Netherlands. The natural habitat of heather species was moorland. At first, natural events like forest fires and storms caused small-scale forest degradation, in addition on the forest degradation accelerated due to cultural activities like forest grazing, wood cutting and shifting cultivation. Heather plants invaded on degraded forest soils and heaths developed. People learned to use the heaths for economic and cultural purposes. The impact of the heath management on landscape and soils was registered in soil records of barrows, drift sand sequences and plaggic Anthrosols. Based on pollen diagrams of such records we could reconstruct that heaths were developed and used for cattle grazing before the Bronze Age. During the Late Neolithic, the Bronze Age and Iron Age, people created the barrow landscape on the ancestral heaths. After the Iron Age people probably continued with cattle grazing on the heaths and plaggic agriculture until the Early Middle Ages. After 1000 AD two events affected the heaths. At first deforestation for the sale of wood resulted in the first regional extension of sand drifting and heath degradation. After that the introduction of the deep stable economy and heath sods digging resulted in acceleration of the rise of plaggic horizons, severe heath degradation and the second extension of sand drifting. At the end of the 19th century the heath lost its economic value due to the introduction of chemical fertilizers. The heaths were transformed into 'new' arable fields and forests and due to deep ploughing most soil archives were destroyed. Since 1980 AD, the remaining relicts of the ancestral heaths are

  6. Clusters of ancestrally related genes that show paralogy in whole or in part are a major feature of the genomes of humans and other species.

    Directory of Open Access Journals (Sweden)

    Michael B Walker

    Full Text Available Arrangements of genes along chromosomes are a product of evolutionary processes, and we can expect that preferable arrangements will prevail over the span of evolutionary time, often being reflected in the non-random clustering of structurally and/or functionally related genes. Such non-random arrangements can arise by two distinct evolutionary processes: duplications of DNA sequences that give rise to clusters of genes sharing both sequence similarity and common sequence features and the migration together of genes related by function, but not by common descent. To provide a background for distinguishing between the two, which is important for future efforts to unravel the evolutionary processes involved, we here provide a description of the extent to which ancestrally related genes are found in proximity.Towards this purpose, we combined information from five genomic datasets, InterPro, SCOP, PANTHER, Ensembl protein families, and Ensembl gene paralogs. The results are provided in publicly available datasets ( describing the extent to which ancestrally related genes are in proximity beyond what is expected by chance (i.e. form paraclusters in the human and nine other vertebrate genomes, as well as the D. melanogaster, C. elegans, A. thaliana, and S. cerevisiae genomes. With the exception of Saccharomyces, paraclusters are a common feature of the genomes we examined. In the human genome they are estimated to include at least 22% of all protein coding genes. Paraclusters are far more prevalent among some gene families than others, are highly species or clade specific and can evolve rapidly, sometimes in response to environmental cues. Altogether, they account for a large portion of the functional clustering previously reported in several genomes.

  7. Coalescent models reveal the relative roles of ancestral polymorphism, vicariance, and dispersal in shaping phylogeographical structure of an African montane forest robin. (United States)

    Bowie, Rauri C K; Fjeldså, Jon; Hackett, Shannon J; Bates, John M; Crowe, Timothy M


    Although many studies have documented the effect of glaciation on the evolutionary history of Northern Hemisphere flora and fauna, this study is the first to investigate how the indirect aridification of Africa caused by global cooling in response to glacial cycles at higher latitudes has influenced the evolutionary history of an African montane bird. Mitochondrial DNA sequences from the NADH 3 gene were collected from 283 individual Starred Robins (Pogonocichla stellata, Muscicapoidea). At least two major vicariant events, one that separated the Albertine Rift from all but the Kenyan Highlands around 1.3-1.2 Myrs BP, and another that separated the Kenyan Highlands from the northern Eastern Arc, and the northern Eastern Arc from the south-central Eastern Arc between 0.9 and 0.8 Myrs BP appear to underlie much of the observed genetic diversity and structure within Starred Robin populations. These dates of divergence suggest a lack of recurrent gene flow; although the Albertine Rift and south-central Eastern Arc share haplotypes, based on coalescent analyses this can confidently be accounted for by ancestral polymorphism as opposed to recurrent gene flow. Taken collectively, strong evidence exists for recognition of four major ancestral populations: (1) Kenyan Highlands (subspecies keniensis), (2) Albertine Rift (ruwenzori), (3) northern Eastern Arc (helleri), and (4) south-central Eastern Arc, Ufipa and the Malawi Rift (orientalis). The estimated divergence times cluster remarkably around one of the three estimated peaks of aridification in Africa during the Plio-Pleistocene centred on 1 Myrs BP. Further, time to most recent common ancestor (TMRCA) estimates (1.7-1.6 Myrs BP) of gene divergence between the Albertine Rift and the other montane highlands corresponds closely with a second estimated peak of aridification at about 1.7 Myrs BP. Collectively, these results suggest that aridification of Africa in response to glaciation at higher latitudes during the

  8. Provenance, volcanic record, and tectonic setting of the Paleozoic Ventania Fold Belt and the Claromecó Foreland Basin: Implications on sedimentation and volcanism along the southwestern Gondwana margin (United States)

    Alessandretti, Luciano; Philipp, Ruy Paulo; Chemale, Farid; Brückmann, Matheus Philipe; Zvirtes, Gustavo; Matté, Vinícius; Ramos, Victor A.


    This study focuses on the provenance, volcanic record, and tectonic setting of the Paleozoic Ventania System, a geologic province which comprises the Cambro-Devonian Ventania Fold Belt and the adjoining Permo-Carboniferous Claromecó Foreland Basin, located inboard the deformation front. The Ventania Fold Belt is formed of the Curamalal and Ventana groups, which are composed mainly of mature quartzites that were unconformably deposited on igneous and metamorphic basement. The Pillahuincó Group is exposed as part of the Claromecó Basin and it has lithological and structural features totally distinct from the lowermost groups. This group is composed of immature arkoses and subarkoses with intercalated tuff horizons, unconformably overlaying the quartzites and associated with glacial-marine deposits of the lower Late Carboniferous to Early Permian section. The petrography, as well as major and trace elements (including rare earth elements) support that the Ventania quartzites were derived from cratonic sources and deposited in a passive margin environment. For the Pillahuincó Group, we suggest a transition between rocks derived from and deposited in a passive margin environment to those with geochemical and petrographical signatures indicative of an active continental margin provenance. LA-MC-ICP-MS analysis performed on euhedral and prismatic zircon grains of the tuffs revealed an age of 284 ± 15 Ma. The geochemical fingerprints and geochronological data of the tuffs found in the Claromecó Basin support the presence of an active and widespread Lower Permian pyroclastic activity in southwestern Gondwana, which is interpreted as part of the Choiyoi Volcanic Province in Argentina and Chile.

  9. Pacific Northwest Storms Situation Report # 1

    Energy Technology Data Exchange (ETDEWEB)



    Severe wind and snow storms hit the Pacific Northwest region on December 14 – 15, 2006, following severe flooding during the past few days. The severe weather resulted in major power outages through the region. At peak there were 1.8 million customers without power which included BC Hydro in Canada. Currently, there are over 1.5 million outages in the region as a result of the Pacific Northwest Storms. This represents about 42 percent of customers in affected utility service areas in Oregon and Washington. See table below. Because the current wind and snow storms are coming on the heels of extensive flooding in the region, electric utilities are experiencing damage. Wind gusts reached close to 100 mph in some areas of the region. The storm is expected to bring its strong winds and heavy snow into Idaho, Montana and Wyoming Friday and into the weekend. There are currently no reported major impacts to the petroleum and natural gas infrastructure.

  10. The Pacific Obesity Prevention in Communities project

    DEFF Research Database (Denmark)

    Swinburn, B A; Millar, L; Utter, J;


    , Tonga, New Zealand and Australia) designed to prevent adolescent obesity. This paper overviews the project and the methods common to the four countries. Each country implemented a community-based intervention programme promoting healthy eating, physical activity and healthy weight in adolescents......Obesity is increasing worldwide with the Pacific region having the highest prevalence among adults. The most common precursor of adult obesity is adolescent obesity making this a critical period for prevention. The Pacific Obesity Prevention in Communities project was a four-country project (Fiji....... A community capacity-building approach was used, with common processes employed but with contextualized interventions within each country. Changes in anthropometric, behavioural and perception outcomes were evaluated at the individual level and school environments and community capacity at the settings level...

  11. 2009 Hands Across Pacific Show Held

    Institute of Scientific and Technical Information of China (English)


    <正>The 2009 Hands Across the Pacific Show co-sponsored by the Canadian International Cultural Exchanges (CICEX) and Hunan Provincial People’s Association for Friendship with Foreign Countries(HPPAFFC) was held respectively in the Tower Hall of Tokyo,Japan from July 2 to 7 and in the Hunan Provincial Museum from August 1 to 5.Jing Dunquan,Vice President of the

  12. Assistance Focus: Asia/Pacific Region

    Energy Technology Data Exchange (ETDEWEB)


    The Clean Energy Solutions Center, an initiative of the Clean Energy Ministerial, helps countries throughout the world create policies and programs that advance the deployment of clean energy technologies. Through the Solutions Center's no-cost 'Ask an Expert' service, a team of international experts has delivered assistance to countries in all regions of the world. High-impact examples from the Asia/Pacific region are featured here.

  13. Geothermal Energy in the Pacific Region (United States)


    verted to electricity at the present time at eight sites, briefly descr: in the Pacific region: The Geysers, California; Cerro Prieto , Mexico...New Zealand, the Geysers in California, Lardarello, in Ttaly, and Cerro Prieto , in Mexico, very high temperatures have been hrought close to the...Mexico es The Mexicali-Imperial valley geothermal province extends into north- ern Mexico in the vicinity of Mexicali, and here, at Cerro Prieto , the

  14. Pacific Northwest Storms Situation Report # 4

    Energy Technology Data Exchange (ETDEWEB)



    Significant progress has been made in restoring power to customers in the Pacific Northwest region. Currently, 237,030 customers remain without power. This is down from 1.8 million customers who lost power following severe wind and snow storms on December 14-15, 2006. The customers without power represent about 8 percent of customers in the affected utility service areas of Oregon and Washington.

  15. Pacific Northwest Storms Situation Report # 5

    Energy Technology Data Exchange (ETDEWEB)



    Significant progress has been made in restoring power to customers in the Pacific Northwest region. Currently, 186,627 customers remain without power. The majority of customers without power are served by Puget Sound Energy. This is down from 1.8 million customers who lost power following severe wind and snow storms on December 14-15, 2006. The customers without power represent about 6 percent of customers in the affected utility service areas of Oregon and Washington. See table below.

  16. Rebalance to the Pacific: Resourcing the Strategy (United States)


    concern is the geophysical stability of the ocean floor. Plate tectonics are shifting the sea floor daily, creating constant seismic activity. Known...presence. Marine air-ground task forces (MAGTFs) will not only be located in Hawaii and Japan but also in Guam and Australia. Guam itself will be a...countriesandterritories/northkorea/ index.html. 13 The Pacific Plate is unstable and always shifting, causing plates to slide underneath each other thus creating energy

  17. Newborn screening in the Asia Pacific region. (United States)

    Padilla, Carmencita D; Therrell, Bradford L


    The success of blood spot newborn screening in the USA led to early screening efforts in parts of the Asia Pacific Region in the mid-1960s. While there were early screening leaders in the region, many of the countries with depressed and developing economies are only now beginning organized screening efforts. Four periods of screening growth in the Asia Pacific region were identified. Beginning in the 1960s, blood spot screening began in New Zealand and Australia, followed by Japan and a cord blood screening programme for G6PD deficiency in Singapore. In the 1980s, established programmes added congenital hypothyroidism and new programmes developed in Taiwan, Hong Kong, China (Shanghai), India and Malaysia. Programmes developing in the 1990s built on the experience of others developing more rapidly in Korea, Thailand and the Philippines. In the 2000s, with limited funding support from the International Atomic Energy Agency, there has been screening programme development around detection of congenital hypothyroidism in Indonesia, Mongolia, Sri Lanka, Myanmar and Pakistan. Palau has recently contracted with the Philippine newborn screening programme. There is little information available on newborn screening activities in Nepal, Cambodia, Laos and the other Pacific Island nations, with no organized screening efforts apparent. Since approximately half of the births in the world occur in the Asia Pacific Region, it is important to continue the ongoing implementation and expansion efforts so that these children can attain the same health status as children in more developed parts of the world and their full potential can be realized.

  18. Assistance Focus: Asia/Pacific Region (Brochure)

    Energy Technology Data Exchange (ETDEWEB)


    The Clean Energy Solutions Center Ask an Expert service connects governments seeking policy information and advice with one of more than 30 global policy experts who can provide reliable and unbiased quick-response advice and information. The service is available at no cost to government agency representatives from any country and the technical institutes assisting them. This publication presents summaries of assistance provided to governments in the Asia/Pacific region, including the benefits of that assistance.

  19. Epidemiology of Glaucoma in Asia-Pacific

    Institute of Scientific and Technical Information of China (English)

    P.Siva; Reddy


    Primary open angle glaucoma is the second most important cause of permanent blindness in the Asia Pacific region. Thus it is very important to identify epidemiological and other risk factore which are associated with open angle glaucoma. The risk for glaucoma optic nerve damage increases with the age and with the level of the intraocular pressure. In this paper, I will highlight our study of several risk factors for development of the open angle glaucoma like (1) elevated intraocular pressure, (2) myopi...

  20. 祠堂文化助力农村社区教育发展研究——基于三水祠堂文化活化视角%Research on How Ancestral Temple Culture Boost Rural Community Education Development—— Based on the New Concept of Sanshui Ancestral Temple Culture

    Institute of Scientific and Technical Information of China (English)



    With the development of rural urbanization, value of the rural ancestral temple was slowly highlighted. The traditional sense of the Ancestral temple′s functions such as social education, village autonomy in rural community governance is renewed. The highly fit of the Ancestral temple culture and the rural community education, with its confidence, inheritance, and liberty is helpful to the villagers′cultural consciousness and education consciousness. It is also helpful to the community autonomy, reshaping rural ethics and cultivating the spirit of the rural citizens. With the guidance of the government organizations at all levels, activating the ancestral temple culture and constructing the rural public cultural synthesis is not only an important way for the innovation of the rural education and the rural community governance model, but also the best performance of the new rural villagers′self-conscious to the traditional culture.%随着农村城镇化进程的深入,农村祠堂文化价值突显. 祠堂传统意义上的社会教化、村落自治功能在农村社区治理中重新焕发. 祠堂文化与农村社区教育的高度契合及其置信、传承、自主等优越性有助于村民文化自觉、教育自觉和社区自治,重塑农村伦理道德和培养农村公民精神. 各级政府部门组织引导社会各方力量,活化祠堂文化,积极构建农村公共文化教育综合体是创新农村社区教育和农村社区治理模式的重要途径,更是新农村村民对传统文化自觉的表现.

  1. Central Equatorial Pacific Experiment (CEPEX). Design document

    Energy Technology Data Exchange (ETDEWEB)


    The Earth`s climate has varied significantly in the past, yet climate records reveal that in the tropics, sea surface temperatures seem to have been remarkably stable, varying by less than a few degrees Celsius over geologic time. Today, the large warm pool of the western Pacific shows similar characteristics. Its surface temperature always exceeds 27{degree}C, but never 31{degree}C. Heightened interest in this observation has been stimulated by questions of global climate change and the exploration of stabilizing climate feedback processes. Efforts to understand the observed weak sensitivity of tropical sea surface temperatures to climate forcing has led to a number of competing ideas about the nature of this apparent thermostat. Although there remains disagreement on the processes that regulate tropical sea surface temperature, most agree that further progress in resolving these differences requires comprehensive field observations of three-dimensional water vapor concentrations, solar and infrared radiative fluxes, surface fluxes of heat and water vapor, and cloud microphysical properties. This document describes the Central Equatorial Pacific Experiment (CEPEX) plan to collect such observations over the central equatorial Pacific Ocean during March of 1993.

  2. Pacific Array (Transportable Broadband Ocean Floor Array) (United States)

    Kawakatsu, Hitoshi; Ekstrom, Goran; Evans, Rob; Forsyth, Don; Gaherty, Jim; Kennett, Brian; Montagner, Jean-Paul; Utada, Hisashi


    Based on recent developments on broadband ocean bottom seismometry, we propose a next generation large-scale array experiment in the ocean. Recent advances in ocean bottom broadband seismometry1, together with advances in the seismic analysis methodology, have enabled us to resolve the regional 1-D structure of the entire lithosphere/asthenosphere system, including seismic anisotropy (azimuthal, and hopefully radial), with deployments of ~15 broadband ocean bottom seismometers (BBOBSs). Having ~15 BBOBSs as an array unit for a 2-year deployment, and repeating such deployments in a leap-frog way or concurrently (an array of arrays) for a decade or so would enable us to cover a large portion of the Pacific basin. Such efforts, not only by giving regional constraints on the 1-D structure beneath Pacific ocean, but also by sharing waveform data for global scale waveform tomography, would drastically increase our knowledge of how plate tectonics works on this planet, as well as how it worked for the past 150 million years. International collaborations is essential: if three countries/institutions participate this endeavor together, Pacific Array may be accomplished within five-or-so years.

  3. Eastern tropical North Pacific coral radiocarbon reveals North Pacific Gyre Oscillation (NPGO) variability (United States)

    Rafter, Patrick A.; Sanchez, Sara C.; Ferguson, Julie; Carriquiry, Jose D.; Druffel, Ellen R. M.; Villaescusa, J. A.; Southon, John R.


    Fluctuations in oceanic circulation and upwelling associated with the North Pacific Gyre Oscillation (NPGO) are the largest source of salinity and nutrient concentration variability across the Pacific basin. Recent observations suggest NPGO-like variability is intensifying, but longer, "pre-instrumental" records are required to improve our understanding of NPGO amplitude and phase change. Here, using measurements of coral skeletal chemistry from San Benedicto Island in the Eastern Tropical North Pacific (ETNP), we assess this region's suitability for reconstructing NPGO behavior. We find that coral geochemical proxy measurements of ETNP salinity and dissolved inorganic carbon radiocarbon (Δ14C) content reflect NPGO-driven gyre circulation and regional coastal upwelling. These results provide the basis for reconstructing NPGO-related ocean conditions hundreds of years prior to the modern observational record.

  4. Heat flow in northwest Pacific marginal seas

    Institute of Scientific and Technical Information of China (English)

    JIANG Lili; LI Guanbao; LI Naisheng


    Heat flow studies in Northwest Pacific marginal seas has a more than 40 years history with more than 4000 heat flow values obtained. The regional average value is 80.4 mW/m2, which is lower than the world's 87 mW/m2, but higher than those of the Eurasia continent and the Pacific Ocean. This reflects the regional crust property in the area. The studies on distribution of the heat flow and contour pattern of heat flow in 1°×1°and 2°×2°scales in Northwest Pacific marginal seas revealed that the most high heat flow anomalies in the area were found along back-arc basins and island arc in an obviously northeasterly track. Exceptions are the Komandoskaya Basin (KMB), the Izu-Bonin Trough (IBT) and the Mariana Trough (MT), which extend in northwest. The contours of low heat flow marked the boundaries of the continent and the ocean. The present heat flow values reflect the imprint of the last thermal event and relate closely to tectonic activity. The high heat flow gradient areas have high frequency of earthquake. Therefore, the area of faulting controlled the pattern of the heat flow anomalies. Heat flow gradient in 135°direction indicated a major lithosphere transformation oceanward resulting from movement of the earth's material. In this paper, we described patterns of heat flow distribution in the Northwest Pacific, heat flow value changes in horizontal and vertical directions, combining the studies of Shi (1997) on the landforms of the island arcs in east Asia and plate movement, and the results of Shi and Zhang (1998) on heat simulation of subduction of active ocean mountain and the activity of islands arc. A preliminary model of geodynamics in the Northwest Pacific and its adjacent area was put forward. There is a great lateral heat flow gradient on the surface of the mantle between ocean and continent, which indicates that the materials in asthenosphere move from continent to ocean causing movement of the crust.

  5. Pacific Lamprey Research and Restoration : Annual Report 1996.

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, Aaron D.


    The once abundant stocks of Pacific lamprey (Lampetra tridentata) above Bonneville Dam are currently depressed (Close et al. 1995). It is likely that many of the same factors that led to the decline of wild stocks of Columbia River Pacific salmon and steelhead have impacted Pacific lamprey populations. The Pacific lamprey is an important part of the food web of North Pacific ecosystems, both as predator and prey. Lamprey (a.k.a. eels) are also a valuable food and culture resource for American Indian Tribes of the Pacific Northwest. Depressed Pacific lamprey runs have impacted treaty secured fishing opportunities by forcing tribal members to gather this traditional food in lower Columbia River locations. The Pacific Lamprey Research and Restoration Project, funded by Bonneville Power Administration, is a cooperative effort between the Confederated Tribes of The Umatilla Indian Reservation, the Columbia River Intertribal Fish Commission, and Oregon State University with the goal to increase Pacific lamprey stocks above Bonneville Dam. The initial objectives of the project are to determine the past and current abundance of Pacific lamprey stocks in major mid Columbia tributaries and at various hydroelectric facilities, and to determine factors limiting Pacific lamprey abundance and distribution. Ultimately, Pacific lamprey restoration plans will be developed and implemented. Part (A)-CTUIR: (1) determine past and present abundance and distribution in NE Oregon and SE Washington tributaries; and (2) determine limiting habitat factors. Part (B)-CRITFC: (1) adult abundance monitoring at Columbia and Snake River dams; (2) juvenile abundance monitoring at Columbia and Snake River dams; and (3) juvenile passage impediments and needed improvements at Columbia and Snake River dams. Part (C)- OSU: (1) adult passage impediments and needed improvements at Columbia and Snake River dams; and (2) juvenile passage impediments and needed improvements at Columbia and Snake River dams.

  6. Pacific Decadal Variability and Central Pacific Warming El Niño in a Changing Climate

    Energy Technology Data Exchange (ETDEWEB)

    Di Lorenzo, Emanuele [Georgia Inst. of Technology, Atlanta, GA (United States)


    This research aimed at understanding the dynamics controlling decadal variability in the Pacific Ocean and its interactions with global-scale climate change. The first goal was to assess how the dynamics and statistics of the El Niño Southern Oscillation and the modes of Pacific decadal variability are represented in global climate models used in the IPCC. The second goal was to quantify how decadal dynamics are projected to change under continued greenhouse forcing, and determine their significance in the context of paleo-proxy reconstruction of long-term climate.

  7. Blind to morphology: Genetics identifies several widespread ecologically common species and few endemics among Indo-Pacific cauliflower corals (Pocillopora, Scleractinia)

    KAUST Repository

    Pinzón, Jorge H C


    Aim: Using high-resolution genetic markers on samples gathered from across their wide distributional range, we endeavoured to delimit species diversity in reef-building Pocillopora corals. They are common, ecologically important, and widespread throughout the Indo-Pacific, but their phenotypic plasticity in response to environmental conditions and their nearly featureless microskeletal structures confound taxonomic assignments and limit an understanding of their ecology and evolution. Location: Indo-Pacific, Red Sea, Arabian/Persian Gulf. Methods: Sequence analysis of nuclear ribosomal (internal transcribed spacer 2, ITS2) and mitochondrial (open reading frame) loci were combined with population genetic data (seven microsatellite loci) for Pocillopora samples collected throughout the Indo-Pacific, Red Sea and Arabian Gulf, in order to assess the evolutionary divergence, reproductive isolation, frequency of hybridization and geographical distributions of the genus. Results: Between five and eight genetically distinct lineages comparable to species were identified with minimal or no hybridization between them. Colony morphology was generally incongruent with genetics across the full range of sampling, and the total number of species is apparently consistent with lower estimates from competing morphologically based hypotheses (about seven or eight taxa). The most commonly occurring genetic lineages were widely distributed and exhibited high dispersal and gene flow, factors that have probably minimized allopatric speciation. Uniquely among scleractinian genera, this genus contains a monophyletic group of broadcast spawners that evolved recently from an ancestral brooder. Main conclusions: The delineation of species diversity guided by genetics fundamentally advances our understanding of Pocillopora geographical distributions, ecology and evolution. Because traditional diagnostic features of colony and branch morphology are proving to be of limited utility, the

  8. 76 FR 71321 - North Pacific Fishery Management Council; Public Meetings (United States)


    ... Operations and Procedures (SOPPs) review/approval and update on workshop with International Pacific Halibut... Service Report; Protected Species Report (including Steller Sea Lion (SSL) Center of Independent...

  9. 76 FR 2084 - North Pacific Fishery Management Council; Public Meetings (United States)


    ... discussion paper and TRAWLEX report). Alaska Department of Fish & Game Report. International Pacific Halibut... Species Report (including update on Steller Sea Lion (SSL); Endangered Species Act (ESA) listed...

  10. 78 FR 43125 - Fisheries off West Coast States; Pacific Coast Groundfish Fishery Management Plan; Commercial... (United States)


    ... States; Pacific Coast Groundfish Fishery Management Plan; Commercial, Limited Entry Pacific Coast... Groundfish Fishery Management Plan (FMP). This action proposes to implement trailing actions for the program... time, the Pacific Fishery Management Council (Council) and NMFS have been addressing...

  11. Complementary innate (anti-A-specific) IgM emerging from ontogenic O-GalNAc-transferase depletion: (Innate IgM complementarity residing in ancestral antigen completeness). (United States)

    Arend, Peter


    The murine and the human genome have global properties in common. So the murine anti-A-specific complementary IgM and related human innate isoagglutinin represent developmental, 2-mercaptoethanol-sensitive, complement-binding glycoproteins, which do not arise from any measurable environmentally-induced or auto- immune response. The murine anti-A certainly originates from a cell surface- or cell adhesion molecule, which in the course of germ cell development becomes devoid of O-GalNAc-transferase and is released into the circulation. In human sera the enzyme occurs exclusively in those of blood group A- and AB subjects, while in group O(H) an identically encoded protein lets expect an opposite function and appears in conjunction with a complementary anti-A reactive glycoprotein. Since O-glycosylations rule the carbohydrate metabolism in growth and reproduction processes, we propose that the ancestral histo-(blood)-group A molecule arises in the course of O-GalNAc-glycosylations of glycolipids and protein envelops at progenitor cell surfaces. Germ cell development postulates embryonic stem cell fidelity, which is characterised by persistent production of α-linked O-GalNAc-glycans. They are determined by the A-allele within the human, "complete" histo (blood) group AB(O) structure that in early ontogeny is hypothesised to be synthesised independently from the final phenotype. The structure either passes "completely" through the germline, in transferase-secreting mature tissues becoming the "complete" phenotype AB, or disappears in exhaustive glycotransferase depletion from the differentiating cell surfaces and leaves behind the "incomplete" blood group O-phenotype, which has released a transferase- and O-glycan-depleted, complementary glycoprotein (IgM) into the circulation. The process implies, that in humans the different blood phenotypes evolve from a "complete" AB(O) molecular complex in a distinct enzymatic and/or complement cascade suggesting O

  12. 78 FR 23539 - National Marine Fisheries Service, Pacific Fishery Management Council (Pacific Council); May 6... (United States)


    ..., electronic monitoring, allocation review process, Department of Commerce Office of the Inspector General... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE...), Commerce. ACTION: Notice of public meetings. SUMMARY: The Pacific Council will host a meeting of...

  13. Pn Anisotropy in Old Pacific Lithosphere (United States)

    Shintaku, N.; Forsyth, D. W.; Weeraratne, D. S.


    Pn is the high frequency, scattered P phase guided for great distances within old oceanic lithosphere, which is also known as Po. Two arrays of ocean bottom seismometers were deployed on old (~150-160Ma) seafloor in the northwestern Pacific south of Shatsky Rise for the PLATE experiment (Pacific Lithosphere Anisotropy and Thickness Experiment). More than 5 or 6 Pn phases per day are recorded on these ocean bottom seismometers generated by earthquakes in western Pacific subduction zones during one year of deployment; we used 512 Pn phases from earthquakes with locations reported in routine bulletins. Each array was deployed on a separate limb of a magnetic bight, formed at a ridge-ridge-ridge triple junction. The spreading rates on both limbs were ~ 70mm/yr, and the current plate motion direction in the hotspot coordinate frame is WNW. Our overall goal is to identify the pattern of fossil anisotropy in the old oceanic lithosphere, and dynamically generated anisotropy in underlying asthenosphere using both body waves and surface waves. Using high frequency waves (3-10 Hz), we look at variations of Pn velocities as a function of backazimuth. In the western array, where the spreading direction is parallel to the absolute plate motion direction, we find clear Pn anisotropy with velocities varying from ~8.5 km/s in the spreading direction to ~ 8.0 km/s perpendicular to the spreading direction. However, in the eastern array where the fossil spreading direction is perpendicular to the current plate motion, the velocity variations as a function of backazimuth are much less obvious. This may be due to heterogeneity of anisotropy in the oceanic lithosphere, with the fast direction changing from the fossil direction at shallow levels to the absolute direction at greater depth.

  14. Place in Pacific Islands Climate Education (United States)

    Barros, C.; Koh, M. W.


    Understanding place, including both the environment and its people, is essential to understanding our climate, climate change, and its impacts. For us to develop a sense of our place, we need to engage in multiple ways of learning: observation, experimentation, and opportunities to apply new knowledge (Orr, 1992). This approach allows us to access different sources of knowledge and then create local solutions for local issues. It is especially powerful when we rely on experts and elders in our own community along with information from the global community.The Pacific islands Climate Education Partnership (PCEP) is a collaboration of partners—school systems, nongovernmental organizations, and government agencies—working to support learning and teaching about climate in the Pacific. Since 2009, PCEP partners have been working together to develop and implement classroom resources, curriculum standards, and teacher professional learning opportunities in which learners approach climate change and its impacts first through the lens of their own place. Such an approach to putting place central to teaching and learning about climate requires partnership and opportunities for learners to explore solutions for and with their communities. In this presentation, we will share the work unfolding in the Republic of the Marshall Islands (RMI) as one example of PCEP's approach to place-based climate education. Three weeklong K-12 teacher professional learning workshops took place during June-July 2015 in Majuro, RMI on learning gardens, climate science, and project-based learning. Each workshop was co-taught with local partners and supports educators in teaching climate-related curriculum standards through tasks that can foster sense of place through observation, experimentation, and application of new knowledge. Additionally, we will also share PCEP's next steps in place-based climate education, specifically around emerging conversations about the importance of highlighting

  15. Leptospirosis in the Asia Pacific region

    Directory of Open Access Journals (Sweden)

    Coulombe Caroline


    Full Text Available Abstract Background Leptospirosis is a worldwide zoonotic infection that has been recognized for decades, but the problem of the disease has not been fully addressed, particularly in resource-poor, developing countries, where the major burden of the disease occurs. This paper presents an overview of the current situation of leptospirosis in the region. It describes the current trends in the epidemiology of leptospirosis, the existing surveillance systems, and presents the existing prevention and control programs in the Asia Pacific region. Methods Data on leptospirosis in each member country were sought from official national organizations, international public health organizations, online articles and the scientific literature. Papers were reviewed and relevant data were extracted. Results Leptospirosis is highly prevalent in the Asia Pacific region. Infections in developed countries arise mainly from occupational exposure, travel to endemic areas, recreational activities, or importation of domestic and wild animals, whereas outbreaks in developing countries are most frequently related to normal daily activities, over-crowding, poor sanitation and climatic conditions. Conclusion In the Asia Pacific region, predominantly in developing countries, leptospirosis is largely a water-borne disease. Unless interventions to minimize exposure are aggressively implemented, the current global climate change will further aggravate the extent of the disease problem. Although trends indicate successful control of leptospirosis in some areas, there is no clear evidence that the disease has decreased in the last decade. The efficiency of surveillance systems and data collection varies significantly among the countries and areas within the region, leading to incomplete information in some instances. Thus, an accurate reflection of the true burden of the disease remains unknown.

  16. Energy resources of Pacific Coast of Colombia

    Energy Technology Data Exchange (ETDEWEB)

    Bueno Salazar, R.


    Despite failure of modest exploration efforts to yield commercial hydrocarbon production in the Choco-Pacific coastal basin of Colombia, recent geophysical, geochemical, and surface geologic investigations indicate a potential for petroleum accumulations, which could be related to fields located on the western basins of Ecuador that in fact constitute an extension of the Colombian Pacific geologic scheme. The Choco-Pacific coastal basin of Colombia covers an area of approximately 70,000 km/sup 2/, of which 14,000 km/sup 2/ lies offshore. The structural style of this area corresponds to a convergent plate basin created over folded oceanic sediments and adjacent to the subduction zone. Such a framework could be conducive to an attractive array of potential hydrocarbon-bearing traps. Geochemical knowledge of potential source rocks of Cretaceous and early Tertiary age confers an added attraction to the area. Most evaluations reveal kerogen-rich, gas-prone organic matter. Nevertheless, the existence of oil seeps from Cretaceous outcrops could indicate sufficient thermal maturity for oil generation. Adequate reservoirs could be found in sandy or calcareous rocks of late Eocene to Oligocene age, predominantly of marine origin with an estimated thickness exceeding 20,000 ft. Colombia has been one of the leading world producers of gold and platinum, mostly derived from the vast alluvial cover of the onshore area of the basin. In rocks cropping out in the Western Cordillera (eastern margin of the basin), deposits of potentially commercial value of porphyry copper and molybdenum, as well as massive sulfur, manganese, and bauxite, have been found.

  17. Flexure and rheology of Pacific oceanic lithosphere (United States)

    Hunter, Johnny; Watts, Tony


    The idea of a rigid lithosphere that supports loads through flexural isostasy was first postulated in the late 19th century. Since then, there has been much effort to investigate the spatial and temporal variation of the lithosphere's flexural rigidity, and to understand how these variations are linked to its rheology. We have used flexural modelling to first re-assess the variation in the rigidity of oceanic lithosphere with its age at the time of loading, and then to constrain mantle rheology by testing the predictions of laboratory-derived flow laws. A broken elastic plate model was used to model trench-normal, ensemble-averaged profiles of satellite-derived gravity at the trench-outer rise system of circum-Pacific subduction zones, where an inverse procedure was used to find the best-fit Te and loading conditions. The results show a first-order increase in Te with plate age, which is best fit by the depth to the 400 ± 35°C plate-cooling isotherm. Fits to the observed gravity are significantly improved by an elastic plate that weakens landward of the outer rise, which suggests that bending-induced plate weakening is a ubiquitous feature of circum-Pacific subduction zones. Two methods were used to constrain mantle rheology. In the first, the Te derived by modelling flexural observations was compared to the Te predicted by laboratory-derived yield strength envelopes. In the second, flexural observations were modelled using elastic-plastic plates with laboratory-derived, depth-dependent yield strength. The results show that flow laws for low-temperature plasticity of dry olivine provide a good fit to the observations at circum-Pacific subduction zones, but are much too strong to fit observations of flexure in the Hawaiian Islands region. We suggest that this discrepancy can be explained by differences in the timescale of loading combined with moderate thermal rejuvenation of the Hawaiian lithosphere.

  18. Genomes of Helicobacter pylori from native Peruvians suggest admixture of ancestral and modern lineages and reveal a western type cag-pathogenicity island

    Directory of Open Access Journals (Sweden)

    Rahman Syed


    Full Text Available Abstract Background Helicobacter pylori is presumed to be co-evolved with its human host and is a highly diverse gastric pathogen at genetic levels. Ancient origins of H. pylori in the New World are still debatable. It is not clear how different waves of human migrations in South America contributed to the evolution of strain diversity of H. pylori. The objective of our 'phylogeographic' study was to gain fresh insights into these issues through mapping genetic origins of H. pylori of native Peruvians (of Amerindian ancestry and their genomic comparison with isolates from Spain, and Japan. Results For this purpose, we attempted to dissect genetic identity of strains by fluorescent amplified fragment length polymorphism (FAFLP analysis, multilocus sequence typing (MLST of the 7 housekeeping genes (atpA, efp, ureI, ppa, mutY, trpC, yphC and the sequence analyses of the babB adhesin and oipA genes. The whole cag pathogenicity-island (cagPAI from these strains was analyzed using PCR and the geographic type of cagA phosphorylation motif EPIYA was determined by gene sequencing. We observed that while European genotype (hp-Europe predominates in native Peruvian strains, approximately 20% of these strains represent a sub-population with an Amerindian ancestry (hsp-Amerind. All of these strains however, irrespective of their ancestral affiliation harbored a complete, 'western' type cagPAI and the motifs surrounding it. This indicates a possible acquisition of cagPAI by the hsp-Amerind strains from the European strains, during decades of co-colonization. Conclusion Our observations suggest presence of ancestral H. pylori (hsp-Amerind in Peruvian Amerindians which possibly managed to survive and compete against the Spanish strains that arrived to the New World about 500 years ago. We suggest that this might have happened after native Peruvian H. pylori strains acquired cagPAI sequences, either by new acquisition in cag-negative strains or by recombination

  19. Comparison with ancestral diets suggests dense acellular carbohydrates promote an inflammatory microbiota, and may be the primary dietary cause of leptin resistance and obesity

    Directory of Open Access Journals (Sweden)

    Spreadbury I


    Full Text Available Ian SpreadburyGastrointestinal Diseases Research Unit, Queen's University, Kingston, Ontario, CanadaAbstract: A novel hypothesis of obesity is suggested by consideration of diet-related inflammation and evolutionary medicine. The obese homeostatically guard their elevated weight. In rodent models of high-fat diet-induced obesity, leptin resistance is seen initially at vagal afferents, blunting the actions of satiety mediators, then centrally, with gastrointestinal bacterial-triggered SOCS3 signaling implicated. In humans, dietary fat and fructose elevate systemic lipopolysaccharide, while dietary glucose also strongly activates SOCS3 signaling. Crucially however, in humans, low-carbohydrate diets spontaneously decrease weight in a way that low-fat diets do not. Furthermore, nutrition transition patterns and the health of those still eating diverse ancestral diets with abundant food suggest that neither glycemic index, altered fat, nor carbohydrate intake can be intrinsic causes of obesity, and that human energy homeostasis functions well without Westernized foods containing flours, sugar, and refined fats. Due to being made up of cells, virtually all "ancestral foods" have markedly lower carbohydrate densities than flour- and sugar-containing foods, a property quite independent of glycemic index. Thus the "forgotten organ" of the gastrointestinal microbiota is a prime candidate to be influenced by evolutionarily unprecedented postprandial luminal carbohydrate concentrations. The present hypothesis suggests that in parallel with the bacterial effects of sugars on dental and periodontal health, acellular flours, sugars, and processed foods produce an inflammatory microbiota via the upper gastrointestinal tract, with fat able to effect a "double hit" by increasing systemic absorption of lipopolysaccharide. This model is consistent with a broad spectrum of reported dietary phenomena. A diet of grain-free whole foods with carbohydrate from cellular

  20. The impact of ancestral heath management on soils and landscapes: a reconstruction based on paleoecological analyses of soil records in the central and southeastern Netherlands (United States)

    Doorenbosch, Marieke; van Mourik, Jan M.


    The evolution of heathlands during the Holocene has been registered in various soil records. Paleoecological analyses of these records enable reconstruction of the changing economic and cultural management of heaths and the consequences for landscape and soils. Heaths are characteristic components of cultural landscape mosaics on sandy soils in the Netherlands. The natural habitat of heather species was moorland. At first, natural events like forest fires and storms caused small-scale forest degradation; in addition on that, the forest degradation accelerated due to cultural activities like forest grazing, wood cutting, and shifting cultivation. Heather plants invaded degraded forest soils, and heaths developed. People learned to use the heaths for economic and cultural purposes. The impact of the heath management on landscape and soils was registered in soil records of barrows, drift sand sequences, and plaggic Anthrosols. Based on pollen diagrams of such records we could reconstruct that heaths were developed and used for cattle grazing before the Bronze Age. During the late Neolithic, the Bronze Age, and Iron Age, people created the barrow landscape on the ancestral heaths. After the Iron Age, people probably continued with cattle grazing on the heaths and plaggic agriculture until the early Middle Ages. Severe forest degradation by the production of charcoal for melting iron during the Iron Age till the 6th-7th century and during the 11th-13th century for the trade of wood resulted in extensive sand drifting, a threat to the valuable heaths. The introduction of the deep, stable economy and heath sods digging in the course of the 18th century resulted in acceleration of the rise of plaggic horizons, severe heath degradation, and again extension of sand drifting. At the end of the 19th century heath lost its economic value due to the introduction of chemical fertilizers. The heaths were transformed into "new" arable fields and forests, and due to deep ploughing

  1. The vertebrate makorin ubiquitin ligase gene family has been shaped by large-scale duplication and retroposition from an ancestral gonad-specific, maternal-effect gene

    Directory of Open Access Journals (Sweden)

    Volff Jean-Nicolas


    Full Text Available Abstract Background Members of the makorin (mkrn gene family encode RING/C3H zinc finger proteins with U3 ubiquitin ligase activity. Although these proteins have been described in a variety of eukaryotes such as plants, fungi, invertebrates and vertebrates including human, almost nothing is known about their structural and functional evolution. Results Via partial sequencing of a testis cDNA library from the poeciliid fish Xiphophorus maculatus, we have identified a new member of the makorin gene family, that we called mkrn4. In addition to the already described mkrn1 and mkrn2, mkrn4 is the third example of a makorin gene present in both tetrapods and ray-finned fish. However, this gene was not detected in mouse and rat, suggesting its loss in the lineage leading to rodent murids. Mkrn2 and mkrn4 are located in large ancient duplicated regions in tetrapod and fish genomes, suggesting the possible involvement of ancestral vertebrate-specific genome duplication in the formation of these genes. Intriguingly, many mkrn1 and mkrn2 intronless retrocopies have been detected in mammals but not in other vertebrates, most of them corresponding to pseudogenes. The nature and number of zinc fingers were found to be conserved in Mkrn1 and Mkrn2 but much more variable in Mkrn4, with lineage-specific differences. RT-qPCR analysis demonstrated a highly gonad-biased expression pattern for makorin genes in medaka and zebrafish (ray-finned fishes and amphibians, but a strong relaxation of this specificity in birds and mammals. All three mkrn genes were maternally expressed before zygotic genome activation in both medaka and zebrafish early embryos. Conclusion Our analysis demonstrates that the makorin gene family has evolved through large-scale duplication and subsequent lineage-specific retroposition-mediated duplications in vertebrates. From the three major vertebrate mkrn genes, mkrn4 shows the highest evolutionary dynamics, with lineage-specific loss of zinc

  2. 4th Pacific Rim Underwater Acoustics Conference

    CERN Document Server

    Xu, Wen; Cheng, Qianliu; Zhao, Hangfang


    These proceedings are a collection of 16 selected scientific papers and reviews by distinguished international experts that were presented at the 4th Pacific Rim Underwater Acoustics Conference (PRUAC), held in Hangzhou, China in October 2013. The topics discussed at the conference include internal wave observation and prediction; environmental uncertainty and coupling to sound propagation; environmental noise and ocean dynamics; dynamic modeling in acoustic fields; acoustic tomography and ocean parameter estimation; time reversal and matched field processing; underwater acoustic localization and communication as well as measurement instrumentations and platforms. These proceedings provide insights into the latest developments in underwater acoustics, promoting the exchange of ideas for the benefit of future research.

  3. The Asia-Pacific Strategic Triangle

    DEFF Research Database (Denmark)

    Schmidt, Johannes Dragsbæk


    applicability discussed; third, details about China and India’s relations and responses to the new US policy are being analyzed; the perspective turns to the implications for conflict and security in South Asia with a focus on Afghanistan and Iran where oil and energy security are the main denominators......The objective of this paper is to give insight into the debate over the strategic triangle and how it impacts conflict and security in South Asia. First the new geopolitical motives of the United States in the Asia-Pacific are outlined. Then the concept of strategic triangle is elaborated and its...

  4. Pacific Northwest Storms Situation Report # 6

    Energy Technology Data Exchange (ETDEWEB)



    Significant progress has been made in restoring power to customers in the Pacific Northwest region. Currently, 134,868 customers remain without power. The number of outages is down from 1.8 million customers who lost power following severe wind and snow storms on December 14-15, 2006. The customers without power represent less than 5 percent of customers in the affected utility service areas of Oregon and Washington. The majority of customers without power are served by Puget Sound Energy and Seattle City Light.

  5. Pacific Northwest Storms Situation Report # 3

    Energy Technology Data Exchange (ETDEWEB)



    Significant progress has been made in restoring power to customers in the Pacific Northwest region. Currently, 468,200 customers, including Canada, remain without power. This is down from 1.8 million customers who lost power following severe wind and snow storms on December 14-15, 2006. The customers without power represent about 16 percent of customers in the affected utility service areas of Oregon and Washington. See table below. The Olympic pipeline reports that the pipeline is operational; however, pipeline throughput remains reduced since one substation along the line remains without power. Complete power restoration is expected later today. There are no reports of problems regarding fuel distribution and production.

  6. Organizing III MEF in the Pacific (United States)


    Okinawa and Iwakuni .................................................................................22 The Design Answer………………………………………………………………23...Marines on Marine Corps Air Station (MCAS) Iwakuni and other bases in the Pacific, all III MEF personnel reside on Okinawa.6 During the last decade the...that “space from which to maneuver” Admiral Fallon alluded to in his 2006 speech. Japan: Okinawa and Iwakuni The United States and III MEF need the

  7. Mercury in Pacific bluefin tuna (Thunnus orientalis):bioaccumulation and trans-Pacific Ocean migration (United States)

    Colman, John A.; Nogueira, Jacob I.; Pancorbo, Oscar C.; Batdorf, Carol A.; Block, Barbara A.


    Pacific bluefin tuna (Thunnus orientalis) have the largest home range of any tuna species and are well known for the capacity to make transoceanic migrations. We report the measurement of mercury (Hg) concentrations in wild Pacific bluefin tuna (PBFT), the first reported with known size-of-fish and capture location. The results indicate juvenile PBFT that are recently arrived in the California Current from the western Pacific Ocean have significantly higher Hg concentrations in white muscle (0.51 ug/g wet mass, wm) than PBFT of longer California Current residency (0.41 ug/g wm). These new arrivals are also higher in Hg concentration than PBFT in farm pens (0.43 ug/g wm) that were captured on arrival in the California Current and raised in pens on locally derived feed. Analysis by direct Hg analyzer and attention to Hg by tissue type and location on the fish allowed precise comparisons of mercury among wild and captive fish populations. Analysis of migration and nearshore residency, determined through extensive archival tagging, bioaccumulation models, trophic investigations, and potential coastal sources of methylmercury, indicates Hg bioaccumulation is likely greater for PBFT juvenile habitats in the western Pacific Ocean (East China Sea, Yellow Sea) than in the eastern Pacific Ocean (California Current). Differential bioaccumulation may be a trophic effect or reflect methylmercury availability, with potential sources for coastal China (large hypoxic continental shelf receiving discharge of three large rivers, and island-arc volcanism) different from those for coastal Baja California (small continental shelf, no large rivers, spreading-center volcanism).

  8. Tectonic map of the Circum-Pacific region, Pacific basin sheet (United States)

    Scheibner, E.; Moore, G.W.; Drummond, K.J.; Dalziel, Corvalan Q.J.; Moritani, T.; Teraoka, Y.; Sato, T.; Craddock, C.


    Circum-Pacific Map Project: The Circum-Pacific Map Project was a cooperative international effort designed to show the relationship of known energy and mineral resources to the major geologic features of the Pacific basin and surrounding continental areas. Available geologic, mineral, and energy-resource data are being complemented by new, project-developed data sets such as magnetic lineations, seafloor mineral deposits, and seafloor sediment. Earth scientists representing some 180 organizations from more than 40 Pacific-region countries are involved in this work. Six overlapping equal-area regional maps at a scale of 1:10,000,000 form the cartographic base for the project: the four Circum-Pacific Quadrants (Northwest, Southwest, Southeast, and Northeast), and the Antarctic and Arctic Sheets. There is also a Pacific Basin Sheet at a scale of 1:17,000,000. The Base Map Series and the Geographic Series (published from 1977 to 1990), the Plate-Tectonic Series (published in 1981 and 1982), the Geodynamic Series (published in 1984 and 1985), and the Geologic Series (published from 1984 to 1989) all include six map sheets. Other thematic map series in preparation include Mineral-Resources, Energy-Resources and Tectonic Maps. Altogether, more than 50 map sheets are planned. The maps were prepared cooperatively by the Circum-Pacific Council for Energy and Mineral Resources and the U.S. Geological Survey and are available from the Branch of Distribution, U. S. Geological Survey, Box 25286, Federal Center, Denver, Colorado 80225, U.S.A. The Circum-Pacific Map Project is organized under six panels of geoscientists representing national earth-science organizations, universities, and natural-resource companies. The six panels correspond to the basic map areas. Current panel chairmen are Tomoyuki Moritani (Northwest Quadrant), R. Wally Johnson (Southwest Quadrant), Ian W.D. Dalziel (Antarctic Region), vacant. (Southeast Quadrant), Kenneth J. Drummond (Northeast Quadrant), and

  9. 75 FR 76294 - Radio Broadcasting Services: Pacific Junction, IA (United States)


    ... From the Federal Register Online via the Government Publishing Office FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 73 Radio Broadcasting Services: Pacific Junction, IA AGENCY: Federal Communications Commission. ACTION: Final rule. SUMMARY: The staff deletes FM Channel 299C2 at Pacific Junction,...

  10. 7 CFR 1124.2 - Pacific Northwest marketing area. (United States)


    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Pacific Northwest marketing area. 1124.2 Section 1124.2 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE PACIFIC NORTHWEST MARKETING AREA...

  11. Festival of Pacific Arts: Education in Multi-Cultural Encounters (United States)

    d'Hauteserre, Anne-Marie


    Can acts of support and/or revival of Pacific cultures serve to educate international tourists about Indigenous cultures? This paper examines, from a postcolonial perspective and using a qualitative methodology, whether the Festivals of Pacific Arts, to which all nations send delegations, can educate visitors about Indigenous cultures of the…

  12. 21 CFR 161.170 - Canned Pacific salmon. (United States)


    ... forms of canned Pacific salmon are processed from fish prepared by removing the head, gills, and tail... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Canned Pacific salmon. 161.170 Section 161.170... FOR HUMAN CONSUMPTION FISH AND SHELLFISH Requirements for Specific Standardized Fish and...

  13. Pacific Lamprey Research and Restoration Project : Annual Report 2000.

    Energy Technology Data Exchange (ETDEWEB)

    Close, David A.


    This report summarizes results of research activities conducted in 1999-2000. The findings in these chapters represent the efforts of the Confederated Tribes of the Umatilla Indian Reservation (CTUIR) and collaborative efforts among other researchers working on Pacific lampreys (Lampetra tridentata) under this project. The findings in these chapters will help management and recovery of Pacific lampreys in the Columbia River Basin.

  14. Governance, Corruption, and Trade in the Asia Pacific Region


    Abe, Kazutomo; Wilson, John S.


    This paper examines the impact of reducing corruption and improving transparency to lower trade costs in the Asia Pacific Economic Cooperation region. The authors find, based on a computable general equilibrium model, significant potential trade and welfare gains for Asia Pacific Economic Cooperation members, with increased transparency and lower levels of corruption. Results suggest that ...

  15. Education Concerns of Asian and Pacific Americans. 1978 Conference Report. (United States)

    Takei, Barbara

    Five national issues considered to be the most important to Asian and Pacific Americans' (APA) education priorities are discussed in this report. These include the need to: (1) increase Federal assistance and improve access for APAs; (2) gather more data and research on APA education needs; (3) promote more Asian and Pacific American participation…

  16. 76 FR 55614 - Airworthiness Directives; Pacific Aerospace Limited Airplanes (United States)


    ... Order 12866; 2. Is not a ``significant rule'' under the DOT Regulatory Policies and Procedures (44 FR... Federal Aviation Administration 14 CFR Part 39 RIN 2120-AA64 Airworthiness Directives; Pacific Aerospace... (AD) for Pacific Aerospace Limited Models FU24-954 and FU24A-954 airplanes modified with an...

  17. Shaping Education Policy Research in an Asia-Pacific Context (United States)

    Jeong, Dong Wook; Lee, Ho Jun; Lee, Seung Ho; Wi, Eunjoo


    Globalization increasingly calls for comparing educational policies across countries. In this study, we assemble and analyze academic journal publications of the past decade in order to shape education policy research within an Asia-Pacific context. After examining Asia-Pacific research publication data from the Web of Science, we find a few…

  18. 33 CFR 334.1340 - Pacific Ocean, Hawaii; danger zones. (United States)


    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Pacific Ocean, Hawaii; danger... ARMY, DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.1340 Pacific Ocean, Hawaii; danger zones. (a) Danger zones—(1) Aerial bombing and strafing target surrounding Kaula...

  19. 76 FR 16618 - Western Pacific Fishery Management Council; Public Meetings (United States)


    ... Mandates A. Coastal and Marine Spatial Planning (CMSP) i. Overview of CMSP ii. Community CMSP Workshop... A. Coastal and Marine Spatial Planning (CMSP) i. Overview of CMSP ii. Community CMSP Workshop Plans... Initiatives A. Coastal and Marine Spatial Planning i. Pacific Islands Regional Office ii. Pacific...

  20. 75 FR 8674 - Western Pacific Fishery Management Council; Public Meetings (United States)


    ... Spatial Planning, coral reef ecosystem threats, truth in science, Western and Central Pacific Fisheries.... NOAA Draft Catch Shares Policy E. National Ocean Policy and Marine Spatial Planning F. Local, National... the Pacific Islands Fisheries Science Center Director 5. Program Planning A. ACLs...