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Sample records for fossil beds early

  1. Deciphering the depositional environment of the laminated Crato fossil beds (Early Cretaceous, Araripe Basin, North-eastern Brazil)

    DEFF Research Database (Denmark)

    Heimhofer, Ulrich; Ariztegui, Daniel; Lenniger, Marc

    2010-01-01

    The laminated limestones of the Early Cretaceous Crato Formation of the Araripe Basin (North-eastern Brazil) are world-famous for their exceptionally well-preserved and taxonomically diverse fossil fauna and flora. Whereas the fossil biota has received considerable attention, only a few studies...... bedded, pale to dark lamination. To obtain information on palaeoenvironmental conditions, sample slabs derived from three local stratigraphic sections within the Araripe Basin were studied using high-resolution multiproxy techniques including detailed logging, petrography, mu-XRF scanning and stable......-poor meteoric water source and support a continental freshwater setting for the Nova Olinda Member. The delta C-13 values, which are comparatively rich in C-13 (between -0.1 and +1.9 parts per thousand), are interpreted to reflect reduced throughflow of water in a restricted basin, promoting...

  2. Radioactivity in fossils at the Hagerman Fossil Beds National Monument.

    Science.gov (United States)

    Farmer, C Neal; Kathren, Ronald L; Christensen, Craig

    2008-08-01

    Since 1996, higher than background levels of naturally occurring radioactivity have been documented in both fossil and mineral deposits at Hagerman Fossil Beds National Monument in south-central Idaho. Radioactive fossil sites occur primarily within an elevation zone of 900-1000 m above sea level and are most commonly found associated with ancient river channels filled with sand. Fossils found in clay rich deposits do not exhibit discernable levels of radioactivity. Out of 300 randomly selected fossils, approximately three-fourths exhibit detectable levels of natural radioactivity ranging from 1 to 2 orders of magnitude above ambient background levels when surveyed with a portable hand held Geiger-Muller survey instrument. Mineral deposits in geologic strata also show above ambient background levels of radioactivity. Radiochemical lab analysis has documented the presence of numerous natural radioactive isotopes. It is postulated that ancient groundwater transported radioactive elements through sand bodies containing fossils which precipitated out of solution during the fossilization process. The elevated levels of natural radioactivity in fossils may require special precautions to ensure that exposures to personnel from stored or displayed items are kept as low as reasonably achievable (ALARA).

  3. Precious Fossil-Bearing Beds of the Lower Cretaceous Jiufotang Formation in Western Liaoning Province, China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Lijun; YANG Yajun; ZHANG Lidong; GUO Shengzhe; WANG Wuli; ZHENG Shaolin

    2007-01-01

    Based on the subdivision into three members of the Lower Cretaceous Jiufotang Formation in western Liaoning, this paper deals mainly with the division and correlation of precious fossil birdand reptile-bearing beds of the formation in the Dachengzi, Chaoyang, Dapingfang-Meileyingzi and Fuxin-Yixian basins. Among them, the precious fossil-bearing beds in the Dachengzi Basin may be recognized as the Xidagou Bed of the second member and the Yangcaogoudonggou Bed of the third member; those in the Chaoyang Basin may be confirmed as the Shangheshou Bed of the second member and the Dongpochi Bed of the third member; those in the Dapingfang-Meileyingzi Basin are as the Lamagou Bed of the second member, the Huanghuagou Bed of the lower third member and the Yuanjiawa Bed of the upper third member; and those in the Fuxin-Yixian Basin are listed as the Tuanshanzi Bed of the second member and the Pijiagou Bed of the third member. Since these basins are distinctly separated and the bird and reptile fossils are mostly new genera and species, we have to use the associated fossil ostracod assemblages as index to correlate the Xidagou Bed with the Shangheshou Bed and the Lamagou Bed, and to correlate the Yuanjiawa Bed with the Yangcaogoudonggou Bed and the Pijiagou Bed. Primarily, we established the sequence of the precious fossil-bearing beds of the Jiufotang Formation in western Liaoning. They are represented by, in ascending order, the Xidagou Bed of the second member, the Huanghuagou Bed of the lower third member, and the Yuanjiawa Bed of the upper third member. Obviously, this work has significance for the study on the time-space distribution and radiation of birds and dinosaurs during the period of the middle Early Cretaceous.

  4. Geologic History of Eocene Stonerose Fossil Beds, Republic, Washington, USA

    Directory of Open Access Journals (Sweden)

    George E. Mustoe

    2015-07-01

    Full Text Available Eocene lakebed sediments at Stonerose Interpretive Center in Republic, Washington, USA are one of the most important Cenozoic fossil sites in North America, having gained international attention because of the abundance and diversity of plant, insect, and fish fossils. This report describes the first detailed geologic investigation of this unusual lagerstätten. Strata are gradationally divided into three units: Siliceous shale that originated as diatomite, overlain by laminated mudstone, which is in turn overlain by massive beds of lithic sandstone. The sedimentary sequence records topographic and hydrologic changes that caused a deep lake to become progressively filled with volcaniclastic detritus from earlier volcanic episodes. The location of the ancient lake within an active graben suggests that displacements along the boundary faults were the most likely trigger for changes in depositional processes.

  5. Distribution of Exotic Vegetation at Florissant Fossil Beds National Monument, Colorado (Linear Features)

    Data.gov (United States)

    National Park Service, Department of the Interior — This is a coverage showing the exotic vegetation distributions within Florissant Fossil Beds National Monument (FLFO). Data was collected using a Trimble Navigation...

  6. Distribution of Exotic Vegetation at Florissant Fossil Beds National Monument, Colorado (Point Features)

    Data.gov (United States)

    National Park Service, Department of the Interior — This is a point coverage showing the exotic vegetation distributions within Florissant Fossil Beds National Monument (FLFO). Data was collected using a Trimble...

  7. Distribution of Exotic Vegetation at Florissant Fossil Beds National Monument, Colorado (Area Features)

    Data.gov (United States)

    National Park Service, Department of the Interior — This is a region coverage showing the exotic vegetation distributions within Florissant Fossil Beds National Monument (FLFO). Data was collected using a Trimble...

  8. Fossil evidence for the early ant evolution

    Science.gov (United States)

    Perrichot, Vincent; Lacau, Sébastien; Néraudeau, Didier; Nel, André

    2008-02-01

    Ants are one of the most studied insects in the world; and the literature devoted to their origin and evolution, systematics, ecology, or interactions with plants, fungi and other organisms is prolific. However, no consensus yet exists on the age estimate of the first Formicidae or on the origin of their eusociality. We review the fossil and biogeographical record of all known Cretaceous ants. We discuss the possible origin of the Formicidae with emphasis on the most primitive subfamily Sphecomyrminae according to its distribution and the Early Cretaceous palaeogeography. And we review the evidence of true castes and eusociality of the early ants regarding their morphological features and their manner of preservation in amber. The mid-Cretaceous amber forest from south-western France where some of the oldest known ants lived, corresponded to a moist tropical forest close to the shore with a dominance of gymnosperm trees but where angiosperms (flowering plants) were already diversified. This palaeoenvironmental reconstruction supports an initial radiation of ants in forest ground litter coincident with the rise of angiosperms, as recently proposed as an ecological explanation for their origin and successful evolution.

  9. Vertebrate fossils and trace fossils in Upper Jurassic-Lower cretaceous red beds in the Atacama region, Chile

    Science.gov (United States)

    Bell, C. M.; Suárez, M.

    Pterosaur, dinosaur, and crocodile bones are recorded here for the first time in Upper Jurassic-Lower Cretaceous red beds in the Atacama region east of Copiapó, Chile. Trace fossils produced by vertebrate animals include the footprints of theropod dinosaurs and the depressions of sandstone laminae interpreted as burrows and foot impressions. The fossils occur in the 1500-meter-thick Quebrada Monardes Formation, which consists predominantly of the aeolian and alluvial deposits of a semi-arid terrestrial environment. Vertebrate fossils are very rare in Chile. Dinosaur bones and footprints have previously been recorded at only seven locations, and pterosaur remains at only one location. The newly discovered dinosaur bones are the oldest to be described in Chile.

  10. Relation between shell beds and trace fossils of the Albian-Cenomanian Aitamir Formation in Amirabad anticline- northeast Mashhad

    OpenAIRE

    2012-01-01

    Aitamir Formation (Albian-Cenomanian) in the Kopet-Dagh Basin has diverse trace fossils and several shell beds. These trace fossils contain diverse ethological patterns, including domichnia, fodinichnia, grazing, equilibrichnia, navichnia, chemichnia and fugichnia. The types of shell beds distinguished based on differences in sedimentological, palaeoecological and taphonomic features. Shell beds and sandstone layers containing characteristic trace fossils represent a storm-influenced successi...

  11. Enigmatic Fossils from the Lower Carboniferous Shrimp Bed, Granton, Scotland.

    Science.gov (United States)

    Zapalski, Mikołaj K; Clarkson, Euan N K

    2015-01-01

    The Lower Carboniferous (Visean) Granton Lagerstätte (Edinburgh, Scotland) is principally known for the discovery of the conodont animal, but has also yielded numerous crustaceans and other faunas. Here we report on small branching colonies, reaching 10 mm in length. They are small, erect, arborescent, and irregularly branched with predominant monopodial and dichotomous growth. They bud in a single plane. In one specimen the wall microstructure is well preserved and it is composed of evenly spaced, linear fibers, running parallel to the axis of the stems, and connected by transverse bars. We discuss possible biological affinities of these organisms; we consider algal, poriferan, hydrozoan and bryozoan affinities. The general pattern of branching, presence of fan-like structures (interpreted here as possible gonophores) and microstructure suggests affinity to Hydrozoa, affinity to non-calcifying algae is less likely. Assuming hydrozoan nature; the microstructure might suggest affinities with the extant family Solanderiidae Marshall, 1892 that possess an internal chitinous skeleton. The EDS analysis shows that fossils discussed here are preserved as phosphates. The skeletons were probably not mineralized, the presence of phosphorus suggests that the colonies were originally composed of chitin. We describe these organisms as Caledonicratis caridum gen. et sp. nov. (Solanderiidae?, Capitata?). Colonies of C. caridum gen et. sp. nov. sometimes encrust the exuviae of crustaceans, which very probably lived in fresh to brackish water thus indicating a likely habitat of Caledonicratis.

  12. Enigmatic Fossils from the Lower Carboniferous Shrimp Bed, Granton, Scotland.

    Directory of Open Access Journals (Sweden)

    Mikołaj K Zapalski

    Full Text Available The Lower Carboniferous (Visean Granton Lagerstätte (Edinburgh, Scotland is principally known for the discovery of the conodont animal, but has also yielded numerous crustaceans and other faunas. Here we report on small branching colonies, reaching 10 mm in length. They are small, erect, arborescent, and irregularly branched with predominant monopodial and dichotomous growth. They bud in a single plane. In one specimen the wall microstructure is well preserved and it is composed of evenly spaced, linear fibers, running parallel to the axis of the stems, and connected by transverse bars. We discuss possible biological affinities of these organisms; we consider algal, poriferan, hydrozoan and bryozoan affinities. The general pattern of branching, presence of fan-like structures (interpreted here as possible gonophores and microstructure suggests affinity to Hydrozoa, affinity to non-calcifying algae is less likely. Assuming hydrozoan nature; the microstructure might suggest affinities with the extant family Solanderiidae Marshall, 1892 that possess an internal chitinous skeleton. The EDS analysis shows that fossils discussed here are preserved as phosphates. The skeletons were probably not mineralized, the presence of phosphorus suggests that the colonies were originally composed of chitin. We describe these organisms as Caledonicratis caridum gen. et sp. nov. (Solanderiidae?, Capitata?. Colonies of C. caridum gen et. sp. nov. sometimes encrust the exuviae of crustaceans, which very probably lived in fresh to brackish water thus indicating a likely habitat of Caledonicratis.

  13. An early Oligocene fossil demonstrates treeshrews are slowly evolving "living fossils".

    Science.gov (United States)

    Li, Qiang; Ni, Xijun

    2016-01-14

    Treeshrews are widely considered a "living model" of an ancestral primate, and have long been called "living fossils". Actual fossils of treeshrews, however, are extremely rare. We report a new fossil species of Ptilocercus treeshrew recovered from the early Oligocene (~34 Ma) of China that represents the oldest definitive fossil record of the crown group of treeshrews and nearly doubles the temporal length of their fossil record. The fossil species is strikingly similar to the living Ptilocercus lowii, a species generally recognized as the most plesiomorphic extant treeshrew. It demonstrates that Ptilocercus treeshrews have undergone little evolutionary change in their morphology since the early Oligocene. Morphological comparisons and phylogenetic analysis support the long-standing idea that Ptilocercus treeshrews are morphologically conservative and have probably retained many characters present in the common stock that gave rise to archontans, which include primates, flying lemurs, plesiadapiforms and treeshrews. This discovery provides an exceptional example of slow morphological evolution in a mammalian group over a period of 34 million years. The persistent and stable tropical environment in Southeast Asia through the Cenozoic likely played a critical role in the survival of such a morphologically conservative lineage.

  14. Investigation of Fossil Insect Systematics of Specimens Collected at the Clare Quarry Site in the Florissant Fossil Beds, Florissant, Colorado from 1996 to Present

    Science.gov (United States)

    Cancellare, J. A.; Villalobos, J. I.; Lemone, D.

    2012-12-01

    antennae,and leg structures are problematic in most specimens. Other factors affecting specimen quality include specimen orientation, partial specimens due to breaks in the matrix, the degree of preservation and effects of weathering. To date classification is strictly superficial. One of the early objectives of this work was to collect series of the same genera however there is no discernible pattern below the ordinal level. In this phase the primary objective will be to place as many insect specimens into families as possible. Many insect families (but no genera) found in the Florissant persist today. Tools used in the initial sorting and extraction process are pin vices, Exacto Knives, razor blades and a Bausch and Lomb zoom dissecting scope fitted with a circular fluorescent illumination ring with magnification ranging from 7 to 45 diameters. During the summer of 2012, twenty one Tipulid specimens were photographed by the Mid - Atlantic Geo - Image Collection (M.A.G. I. C.), Northern Virginia Community College, in order to test the system's efficacy in specimen comparison within series. Preservation of specimens in the Florissant Fossil Beds occurred during the Eocene - Oligocene Transition. Future use of the results generated in this study may have application in the study of climate change.

  15. Rationale of Early Adopters of Fossil Fuel Divestment

    Science.gov (United States)

    Beer, Christopher Todd

    2016-01-01

    Purpose: This research uses the social science perspectives of institutions, ecological modernization and social movements to analyze the rationale used by the early-adopting universities of fossil fuel divestment in the USA. Design/methodology/approach: Through analysis of qualitative data from interviews with key actors at the universities that…

  16. Rationale of Early Adopters of Fossil Fuel Divestment

    Science.gov (United States)

    Beer, Christopher Todd

    2016-01-01

    Purpose: This research uses the social science perspectives of institutions, ecological modernization and social movements to analyze the rationale used by the early-adopting universities of fossil fuel divestment in the USA. Design/methodology/approach: Through analysis of qualitative data from interviews with key actors at the universities that…

  17. Clustering Fossils from the Early Universe

    CERN Document Server

    Jeong, Donghui

    2012-01-01

    Many inflationary theories introduce new scalar, vector, or tensor degrees of freedom that may then affect the generation of primordial density perturbations. Here we show how to search a galaxy (or 21-cm) survey for the imprint of primordial scalar, vector, and tensor fields. These new fields induce local departures to an otherwise statistically isotropic two-point correlation function, or equivalently, nontrivial four-point correlation functions (or trispectra, in Fourier space), that can be decomposed into scalar, vector, and tensor components. We write down the optimal estimators for these various components and show how the sensitivity to these modes depends on the galaxy-survey parameters. New probes of parity-violating early-Universe physics are also presented.

  18. Early penguin fossils, plus mitochondrial genomes, calibrate avian evolution.

    Science.gov (United States)

    Slack, Kerryn E; Jones, Craig M; Ando, Tatsuro; Harrison, G L Abby; Fordyce, R Ewan; Arnason, Ulfur; Penny, David

    2006-06-01

    Testing models of macroevolution, and especially the sufficiency of microevolutionary processes, requires good collaboration between molecular biologists and paleontologists. We report such a test for events around the Late Cretaceous by describing the earliest penguin fossils, analyzing complete mitochondrial genomes from an albatross, a petrel, and a loon, and describe the gradual decline of pterosaurs at the same time modern birds radiate. The penguin fossils comprise four naturally associated skeletons from the New Zealand Waipara Greensand, a Paleocene (early Tertiary) formation just above a well-known Cretaceous/Tertiary boundary site. The fossils, in a new genus (Waimanu), provide a lower estimate of 61-62 Ma for the divergence between penguins and other birds and thus establish a reliable calibration point for avian evolution. Combining fossil calibration points, DNA sequences, maximum likelihood, and Bayesian analysis, the penguin calibrations imply a radiation of modern (crown group) birds in the Late Cretaceous. This includes a conservative estimate that modern sea and shorebird lineages diverged at least by the Late Cretaceous about 74 +/- 3 Ma (Campanian). It is clear that modern birds from at least the latest Cretaceous lived at the same time as archaic birds including Hesperornis, Ichthyornis, and the diverse Enantiornithiformes. Pterosaurs, which also coexisted with early crown birds, show notable changes through the Late Cretaceous. There was a decrease in taxonomic diversity, and small- to medium-sized species disappeared well before the end of the Cretaceous. A simple reading of the fossil record might suggest competitive interactions with birds, but much more needs to be understood about pterosaur life histories. Additional fossils and molecular data are still required to help understand the role of biotic interactions in the evolution of Late Cretaceous birds and thus to test that the mechanisms of microevolution are sufficient to explain

  19. Aluminum-26 in the early solar system - Fossil or fuel

    Science.gov (United States)

    Lee, T.; Papanastassiou, D. A.; Wasserburg, G. J.

    1977-01-01

    The isotopic composition of Mg was measured in different phases of a Ca-Al-rich inclusion in the Allende meteorite. Large excesses of Mg-26 of up to 10% were found. These excesses correlate strictly with the Al-27/Mg-24 ratio for four coexisting phases with distinctive chemical compositions. Models of in situ decay of Al-26 within the solar system and of mixing of interstellar dust grains containing fossil Al-26 with normal solar system material are presented. The observed correlation provides definitive evidence for the presence of Al-26 in the early solar system. This requires either injection of freshly synthesized nucleosynthetic material into the solar system immediately before condensation and planet formation, or local production within the solar system by intense activity of the early sun. Planets promptly produced from material with the inferred Al-26/Al-27 would melt within about 300,000 years.

  20. Aluminum-26 in the early solar system - Fossil or fuel

    Science.gov (United States)

    Lee, T.; Papanastassiou, D. A.; Wasserburg, G. J.

    1977-01-01

    The isotopic composition of Mg was measured in different phases of a Ca-Al-rich inclusion in the Allende meteorite. Large excesses of Mg-26 of up to 10% were found. These excesses correlate strictly with the Al-27/Mg-24 ratio for four coexisting phases with distinctive chemical compositions. Models of in situ decay of Al-26 within the solar system and of mixing of interstellar dust grains containing fossil Al-26 with normal solar system material are presented. The observed correlation provides definitive evidence for the presence of Al-26 in the early solar system. This requires either injection of freshly synthesized nucleosynthetic material into the solar system immediately before condensation and planet formation, or local production within the solar system by intense activity of the early sun. Planets promptly produced from material with the inferred Al-26/Al-27 would melt within about 300,000 years.

  1. Fossil Microorganisms and Formation of Early Precambrian Weathering Profiles

    Science.gov (United States)

    Rozanov, A. Yu; Astafieva, M. M.; Vrevsky, A. B.; Alfimova, N. A.; Matrenichev, V. A.; Hoover, R. B.

    2009-01-01

    Weathering crusts are the only reliable evidences of the existence of continental conditions. Often they are the only source of information about exogenous processes and subsequently about conditions under which the development of the biosphere occurred. A complex of diverse fossil microorganisms was discovered as a result of Scanning Electron Microscope investigations. The chemical composition of the discovered fossils is identical to that of the host rocks and is represented by Si, Al, Fe, Ca and Mg. Probably, the microorganisms fixed in rocks played the role of catalyst. The decomposition of minerals comprising the rocks and their transformation into clayey (argillaceous) minerals, most likely occurred under the influence of microorganisms. And may be unique weathering crusts of Early Precambrian were formed due to interaction between specific composition of microorganism assemblage and conditions of hypergene transformations. So it is possible to speak about colonization of land by microbes already at that time and about existence of single raw from weathering crusts (Primitive soils) to real soils.

  2. Early to Bed, Early to Rise a Back-To-School Challenge

    Science.gov (United States)

    ... medlineplus.gov/news/fullstory_160532.html Early to Bed, Early to Rise a Back-to-School Challenge ... idea. Allow your kids some quiet time before bed to unwind. "That can include relaxing activities, such ...

  3. Vertebrate paleontology, stratigraphy, and paleohydrology of Tule Springs Fossil Beds National Monument, Nevada (USA)

    Science.gov (United States)

    Springer, Kathleen; Pigati, Jeffery S.; Scott, Eric

    2017-01-01

    Tule Springs Fossil Beds National Monument (TUSK) preserves 22,650 acres of the upper Las Vegas Wash in the northern Las Vegas Valley (Nevada, USA). TUSK is home to extensive and stratigraphically complex groundwater discharge (GWD) deposits, called the Las Vegas Formation, which represent springs and desert wetlands that covered much of the valley during the late Quaternary. The GWD deposits record hydrologic changes that occurred here in a dynamic and temporally congruent response to abrupt climatic oscillations over the last ~300 ka (thousands of years). The deposits also entomb the Tule Springs Local Fauna (TSLF), one of the most significant late Pleistocene (Rancholabrean) vertebrate assemblages in the American Southwest. The TSLF is both prolific and diverse, and includes a large mammal assemblage dominated by Mammuthus columbi and Camelops hesternus. Two (and possibly three) distinct species of Equus, two species of Bison, Panthera atrox, Smilodon fatalis, Canis dirus, Megalonyx jeffersonii, and Nothrotheriops shastensis are also present, and newly recognized faunal components include micromammals, amphibians, snakes, and birds. Invertebrates, plant macrofossils, and pollen also occur in the deposits and provide important and complementary paleoenvironmental information. This field compendium highlights the faunal assemblage in the classic stratigraphic sequences of the Las Vegas Formation within TUSK, emphasizes the significant hydrologic changes that occurred in the area during the recent geologic past, and examines the subsequent and repeated effect of rapid climate change on the local desert wetland ecosystem.

  4. Stratigraphic Changes in the Pliocene Carnivoran Assemblage from Hagerman Fossil Beds National Monument, Idaho

    Directory of Open Access Journals (Sweden)

    Dennis R. Ruez

    2016-03-01

    Full Text Available At least 17 carnivoran taxa occur in the Pliocene Glenns Ferry Formation at Hagerman Fossil Beds National Monument (HAFO, Idaho. This assemblage was examined for stratigraphic changes in species distribution, specimen abundance, and species diversity. Three relatively common mustelids, Trigonictis cookii, Trigonictis macrodon, and Mustela rexroadensis, occur at most stratigraphic levels, but are absent during an interval coinciding with the coolest time segment at HAFO. It is within this gap that two less-common mustelids, Ferinestrix vorax and Buisnictis breviramus, first appear at HAFO; they persist up-section with the more common mustelids listed above. Specimens of Borophagus hilli are restricted to the warm intervals at HAFO, irrespective of the relative abundance of surface water. The other canid at HAFO, Canis lepophagus, is more abundant during the dry intervals at HAFO, regardless of the estimated paleotemperature. Most remarkable is the recovery of many taxa impacted by abrupt climate change, although a notable change is the much higher relative abundance of carnivoran species following a return to warm temperatures.

  5. Water availability and flood hazards in the John Day Fossil Beds National Monument, Oregon

    Science.gov (United States)

    Frank, Frank J.; Oster, E.A.

    1979-01-01

    The rock formations of the John Day Fossil Beds National Monument area are aquifers that can be expected to yield less than 10 gallons of water per minute to wells. The most permeable of the geologic units is the alluvium that occurs at low elevations along the John Day River and most of the smaller streams. Wells in the alluvial deposits can be expected to yield adequate water supplies for recreational areas; also, wells completed in the underlying bedrock at depths ranging from 50 to 200 feet could yield as much as 10 gallons per minute. Pumping tests on two unused wells indicated yields of 8 gallons per minute and 2 gallons per minute. Nine of the ten springs measured in and near the monument area in late August of 1978 were flowing 0.2 to 30 gallons per minute. Only the Cant Ranch spring and the Johnny Kirk Spring near the Sheep Rock unit had flows exceeding 6 gallons per minute. Chemical analyses of selected constituents of the ground water indicated generally low concentrations of dissolved minerals. Although cloudbursts in the Painted Hills unit could generate a flood wave on the valley floors, flood danger can be reduced by locating recreational sites on high ground. The campground in Indian Canyon of the Clarno unit is vulnerable to cloudburst flooding. About 80 percent of the proposed campground on the John Day River in the Sheep Rock unit is above the estimated level of 1-percent chance flood (100-year flood) of the river. The 1-percent chance flood would extend about 120 feet from the riverbank into the upstream end of the campground. (USGS).

  6. Weak magnetic fields in early-type stars: failed fossils

    CERN Document Server

    Braithwaite, Jonathan

    2012-01-01

    Weak magnetic fields have recently been detected in Vega and Sirius. Here, we explore the possibility that these fields are the remnants of some field inherited or created during or shortly after star formation and, unlike true fossil fields, are still evolving as we observe them. The timescale of this evolution is given in terms of the Alfven timescale and the rotation frequency by tau_evol ~ tau_A^2 Omega, which would be comparable to the age of the star. It is shown that it is likely that all intermediate- and high-mass stars contain fields of at least the order of the strength found so far in Vega and Sirius. Faster rotators are expected to have stronger magnetic fields. Stars may experience an increase in field strength during their early main-sequence, but for most of their lives field strength will decrease slowly. The length scale of the magnetic structure on the surface may be small in very young stars but should quickly increase to at least very approximately a fifth of the stellar radius.

  7. Earth's early fossil record: Why not look for similar fossils on Mars?

    Science.gov (United States)

    Awramik, Stanley M.

    1989-01-01

    The oldest evidence of life on Earth is discussed with attention being given to the structure and formation of stromatolites and microfossils. Fossilization of microbes in calcium carbonate or chert media is discussed. In searching for fossil remains on Mars, some lessons learned from the study of Earth's earliest fossil record can be applied. Certain sedimentary rock types and sedimentary rock configurations should be targeted for investigation and returned by the Martian rover and ultimately by human explorers. Domical, columnar to wavy laminated stratiform sedimentary rocks that resemble stromatolites should be actively sought. Limestone, other carbonates, and chert are the favored lithology. Being macroscopic, stromatolites might be recognized by an intelligent unmanned rover. In addition, black, waxy chert with conchoidal fracture should be sought. Chert is by far the preferred lithology for the preservation of microbes and chemical fossils. Even under optimal geological conditions (little or no metamorphism or tectonic alteration, excellent outcrops, and good black chert) and using experienced field biogeologists, the chances of finding well preserved microbial remains in chert are very low.

  8. Sponge fossil assemblage from the Early Cambrian Hetang Formation in southern Anhui

    Institute of Scientific and Technical Information of China (English)

    CHEN Zhe; HU Jie; ZHOU Chuanming; XIAO Shuhai; YUAN Xunlai

    2004-01-01

    Abundant well-preserved large articulated sponge fossils and isolated spicules have been reported from the Early Cambrian Hetang Formation, southern Anhui Province. This unique epifaunal fossil assemblage dominated by articulated sponge fossils is called the Xidi Sponge Fauna.The sponge fauna lived in a quiet oxygenic environment below the storm wave base. Bloom of phytoplankton and rapid sedimentation rate resulted in the deposition of the black shales. Sufficient food supply, lack of other competitors,abundant ecological niches, and demand for oxygen during early Cambrian were in favor of the diversification and evolution of large sponges in the Early Cambrian.

  9. Vermicular fossils in the Early Cambrian Xidashan Formation in the Quruqtagh region of Xinjiang, China

    Institute of Scientific and Technical Information of China (English)

    YANG Ruidong; ZHANG Chuanlin; SONG Guoqi; LUO Xinrong

    2006-01-01

    Large amounts of vermicular fossils and a minor amount of sponge animal fossils have been found in the Early Cambrian Xidashan Formation in the region of Quruqtagh, Xinjiang. Vermicular fossils are generally more than 50 mm long and 0.3-1.4 mm wide; their wrinkled lamellae are microfine with 3-10 pieces within the length of every each millimeter. The fossils are considered to be Sabellidites cambriensis Sokolov (1965). The Xidashan Formation is the highest stratum in which Sabellidites occur, as has been so far reported.

  10. Facts and fancies about early fossil chordates and vertebrates.

    Science.gov (United States)

    Janvier, Philippe

    2015-04-23

    The interrelationships between major living vertebrate, and even chordate, groups are now reasonably well resolved thanks to a large amount of generally congruent data derived from molecular sequences, anatomy and physiology. But fossils provide unexpected combinations of characters that help us to understand how the anatomy of modern groups was progressively shaped over millions of years. The dawn of vertebrates is documented by fossils that are preserved as either soft-tissue imprints, or minute skeletal fragments, and it is sometimes difficult for palaeontologists to tell which of them are reliable vertebrate remains and which merely reflect our idea of an ancestral vertebrate.

  11. Stable isotope-based Plio-Pleistocene ecosystem reconstruction of some of the earliest hominid fossil sites in the East African Rift System (Chiwondo Beds, N Malawi)

    Science.gov (United States)

    Lüdecke, Tina; Thiemeyer, Heinrich; Schrenk, Friedemann; Mulch, Andreas

    2014-05-01

    The isotope geochemistry of pedogenic carbonate and fossil herbivore enamel is a powerful tool to reconstruct paleoenvironmental conditions in particular when climate change plays a key role in the evolution of ecosystems. Here, we present the first Plio-Pleistocene long-term carbon (δ13C), oxygen (δ18O) and clumped isotope (Δ47) records from pedogenic carbonate and herbivore teeth in the Malawi Rift. These data represent an important southern hemisphere record in the East African Rift System (EARS), a key region for reconstructing vegetation patterns in today's Zambezian Savanna and correlation with data on the evolution and migration of early hominids across the Inter-Tropical Convergence Zone. As our study site is situated between the well-known hominid-bearing sites of eastern and southern Africa in the Somali-Masai Endemic Zone and Highveld Grassland it fills an important geographical gap for early hominid research. 5.0 to 0.6 Ma fluviatile and lacustrine deposits of the Chiwondo Beds (NE shore of Lake Malawi) comprise abundant pedogenic carbonate and remains of a diverse fauna dominated by large terrestrial mammals. These sediments are also home to two hominid fossil remains, a mandible of Homo rudolfensis and a maxillary fragment of Paranthropus boisei, both dated around 2.4 Ma. The Chiwondo Beds therefore document early co-existence of these two species. We evaluate δ13C data from fossil enamel of different suid, bovid, and equid species and contrast these with δ13C and δ18O values of pedogenic carbonate. We complement the latter with clumped isotope soil temperature data. Results of almost 800 pedogenic carbonate samples from over 20 sections consistently average δ13C = -8.5 ‰ over the past 5 Ma with no significant short-term δ13C excursions or long-term trends. The data from molar tooth enamel of nine individual suids of the genera Metridiochoerus, Notochoerus and Nyanzachoerus support these findings with average δ13C = -10.0 ‰. The absence

  12. Nitrogen compounds in pressurised fluidised bed gasification of biomass and fossil fuels

    NARCIS (Netherlands)

    De Jong, W.

    2005-01-01

    Fossil fuels still dominate the energy supply in modern societies. The resources, however, are depleting. Therefore, other energy sources are to be exploited further within this century. Biomass is one of the practically CO2 neutral, renewable contributors to the future energy production. Nowadays m

  13. A revised checklist of Nepticulidae fossils (Lepidoptera) indicates an Early Cretaceous origin.

    Science.gov (United States)

    Doorenweerd, Camiel; Nieukerken, Erik J Van; Sohn, Jae-Cheon; Labandeira, Conrad C

    2015-05-27

    With phylogenetic knowledge of Lepidoptera rapidly increasing, catalysed by increasingly powerful molecular techniques, the demand for fossil calibration points to estimate an evolutionary timeframe for the order is becoming an increasingly pressing issue. The family Nepticulidae is a species rich, basal branch within the phylogeny of the Lepidoptera, characterized by larval leaf-mining habits, and thereby represents a potentially important lineage whose evolutionary history can be established more thoroughly with the potential use of fossil calibration points. Using our experience with extant global Nepticulidae, we discuss a list of characters that may be used to assign fossil leaf mines to Nepticulidae, and suggest useful methods for classifying relevant fossil material. We present a checklist of 79 records of Nepticulidae representing adult and leaf-mine fossils mentioned in literature, often with multiple exemplars constituting a single record. We provide our interpretation of these fossils. Two species now are included in the collective generic name Stigmellites: Stigmellites resupinata (Krassilov, 2008) comb. nov. (from Ophiheliconoma) and Stigmellites almeidae (Martins-Neto, 1989) comb. nov. (from Nepticula). Eleven records are for the first time attributed to Nepticulidae. After discarding several dubious records, including one possibly placing the family at a latest Jurassic position, we conclude that the oldest fossils likely attributable to Nepticulidae are several exemplars representing a variety of species from the Dakota Formation (USA). The relevant strata containing these earliest fossils are now dated at 102 Ma (million years ago) in age, corresponding to the latest Albian Stage of the Early Cretaceous. Integration of all records in the checklist shows that a continuous presence of nepticulid-like leaf mines preserved as compression-impression fossils and by amber entombment of adults have a fossil record extending to the latest Early Cretaceous.

  14. Diversity in obscurity: fossil flowers and the early history of angiosperms.

    Science.gov (United States)

    Friis, Else Marie; Pedersen, Kaj Raunsgaard; Crane, Peter R

    2010-02-12

    In the second half of the nineteenth century, pioneering discoveries of rich assemblages of fossil plants from the Cretaceous resulted in considerable interest in the first appearance of angiosperms in the geological record. Darwin's famous comment, which labelled the 'rapid development' of angiosperms an 'abominable mystery', dates from this time. Darwin and his contemporaries were puzzled by the relatively late, seemingly sudden and geographically widespread appearance of modern-looking angiosperms in Late Cretaceous floras. Today, the early diversification of angiosperms seems much less 'rapid'. Angiosperms were clearly present in the Early Cretaceous, 20-30 Myr before they attained the level of ecological dominance reflected in some mid-Cretaceous floras, and angiosperm leaves and pollen show a distinct pattern of steadily increasing diversity and complexity through this interval. Early angiosperm fossil flowers show a similar orderly diversification and also provide detailed insights into the changing reproductive biology and phylogenetic diversity of angiosperms from the Early Cretaceous. In addition, newly discovered fossil flowers indicate considerable, previously unrecognized, cryptic diversity among the earliest angiosperms known from the fossil record. Lineages that today have an herbaceous or shrubby habit were well represented. Monocotyledons, which have previously been difficult to recognize among assemblages of early fossil angiosperms, were also diverse and prominent in many Early Cretaceous ecosystems.

  15. Monsters under the Bed: Critically Investigating Early Years Writing

    Science.gov (United States)

    Melrose, Andrew

    2012-01-01

    "Monsters Under the Bed" is an essential text focussing on critical and contemporary issues surrounding writing for "early years" children. Containing a critically creative and a creatively critical investigation of the cult and culture of the child and childhood in fiction and non-fictional writing, it also contains a wealth of ideas and critical…

  16. The Early Cretaceous Hemeroscopid larva fossils from Beijing, China

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    More than 100 Hemeroscopid larva fossils were discovered from the Lower Cretaceous in Southwest Beijing,which effectively ends the discussion of morphology and makes it more complete. It is assigned within the LibelluIoidea, and shows close evolutionary correlations with modern Libellulidae. Although the wing characters of adult Hemeroscopus from the same formation indicates the close relationship to Aeschnoidea, we suggest that the larvae and the adults were the same species. Therefore, it probably shows the evolutionary ancestors of Libellulidae. Being the fundamental species discriminating Jehol Entomofauna and Lushangfen Entomofauna, Hemeroscopus bears great significance in the study of stratigraphy.``

  17. New group of the Early Palaeozoic conodont-like fossils

    Directory of Open Access Journals (Sweden)

    Hubert Szaniawski

    2015-02-01

    Full Text Available The paper is devoted to the Upper Cambrian and Tremadocian organophosphatic microfossils which were hitherto treated as conodonts and assigned mainly to the genera Coelocerodontus and Viirodus. Individual elements of the fossils, similarly to the elements of conodonts, belonged originally to the multi-element apparatuses. Present studies, based mainly on the collections from Sweden, Poland (core sections, Estonia and Kazakhstan, show that despite the similarities of their individual elements to conodonts, they significantly differ from them in the inner structure, as well as in the construction of the apparatuses composed of them. Elements of their apparatuses are matched in shape to each other and certainly functioned in conjunction, while those belonging to the euconodont apparatuses are usually differentiated in shape and usually functioned in separation. All fossils of this group are provisionally named coelocerodonts in this paper. Their individual elements, as well as the apparatuses composed of them, are similar in construction to those of the genus Phakelodus, which is an ancestor of chaetognaths.

  18. Fossil evidence for a herbaceous diversification of early eudicot angiosperms during the Early Cretaceous.

    Science.gov (United States)

    Jud, Nathan A

    2015-09-07

    Eudicot flowering plants comprise roughly 70% of land plant species diversity today, but their early evolution is not well understood. Fossil evidence has been largely restricted to their distinctive tricolpate pollen grains and this has limited our understanding of the ecological strategies that characterized their primary radiation. I describe megafossils of an Early Cretaceous eudicot from the Potomac Group in Maryland and Virginia, USA that are complete enough to allow reconstruction of important life-history traits. I draw on quantitative and qualitative analysis of functional traits, phylogenetic analysis and sedimentological evidence to reconstruct the biology of this extinct species. These plants were small and locally rare but widespread, fast-growing herbs. They had complex leaves and they were colonizers of bright, wet, disturbance-prone habitats. Other early eudicot megafossils appear to be herbaceous rather than woody, suggesting that this habit was characteristic of their primary radiation. A mostly herbaceous initial diversification of eudicots could simultaneously explain the heretofore sparse megafossil record as well as their rapid diversification during the Early Cretaceous because the angiosperm capacity for fast reproduction and fast evolution is best expressed in herbs. © 2015 The Author(s).

  19. Self-sedimented diatom mats as agents of exceptional fossil preservation in the Oligocene Florissant lake beds, Colorado, United States

    Science.gov (United States)

    Harding, Ian C.; Chant, Loraine S.

    2000-03-01

    Microbial mats play a major role in the formation of exceptionally preserved fossil deposits by overgrowing and binding organic remains and sedimentary particles. This minimizes hydrodynamic and biological disruption of dead organisms and sedimentary laminae, but published works all implicate prokaryotic cyanobacteria as the microbial agent. However, exceptionally well preserved macrofossils of the Oligocene Florissant lake beds (Colorado, United States) are enveloped in matted aggregations of mucous-secreting, pennate diatom frustules. It is suggested that the macrobiota became entrapped in mucous-secreting mats of surface water blooms of planktonic diatoms in lake Florissant. As the mats and the incorporated macrobiota were sedimented out of the water column, the mucosic mats and their associated bacterial communities arrested decay and promoted preservation of refractory tissues. Thus, by a completely different mechanism, the diatom mats fulfilled the same preservational role previously suggested for cyanobacterial mats. This hitherto unrecognized mode of preservation may be an important causative factor in the formation of exceptionally preserved lacustrine fossil biotas.

  20. Fossil echinoid (Echinoidea, Echinodermata diversity of the Early Cretaceous (Hauterivian in the Paris Basin (France

    Directory of Open Access Journals (Sweden)

    Sophie Benetti

    2013-08-01

    Full Text Available This dataset inventories occurrence records of fossil echinoid specimens collected in the Calcaires à Spatangues Formation (CSF that crops out in the southeast of the Paris Basin (France, and is dated from the Acanthodiscus radiatus chronozone (ca. 132 Ma, early Hauterivian, Early Cretaceous. Fossil richness and abundance of the CSF has attracted the attention of palaeontologists since the middle of the nineteenth century. This dataset compiles occurrence data (referenced by locality names and geographic coordinates with decimal numbers of fossil echinoids both collated from the literature published over a century and a half, and completed by data from collection specimens. The dataset also gives information on taxonomy (from species to order and higher taxonomic levels, which has been checked for reliability and consistency. It compiles a total of 628 georeferenced occurrence data of 26 echinoid species represented by 22 genera, 14 families, and 9 orders.

  1. Microbial trace fossils in Antarctica and the search for evidence of early life on Mars

    Science.gov (United States)

    Friedmann, E. Imre; Friedmann, Roseli O.

    1989-01-01

    It is possible to hypothesize that, if microbial life evolved on early Mars, fossil remnants of these organisms may be preserved on the surface. However, the cooling and drying of Mars probably resembled a cold desert and such an environment is not suitable for the process of fossilization. The frigid Ross Desert of Antarctica is probably the closest terrestrial analog to conditions that may have prevailed on the surface of the cooling and drying Mars. In this desert, cryptoendolithic microbial communities live in the airspaces of porous rocks, the last habitable niche in a hostile outside environment. The organisms produce characteristic chemical and physical changes in the rock substrate. Environmental changes (deterioration of conditions) may result in the death of the community. Although no cellular structures are fossilized, the conspicuous changes in the rock substrate are preserved as trace fossils. Likewise, microbial trace fossils (without cellular structures) may also be preserved on Mars: Discontinuities in structure or chemistry of the rock that are independent of physical or chemical gradients may be of biological origin. Ross Desert trace fossils can be used as a model for planning search strategies and for instrument design to find evidence of past Martian life.

  2. Age estimation in fossil hominins: comparing dental development in early Homo with modern humans.

    Science.gov (United States)

    Dean, M Christopher; Liversidge, Helen M

    2015-01-01

    Previous studies have used molar tooth eruption as a comparative marker of maturation in early fossil hominins. However, tooth eruption and tooth formation are independent maturational processes. To determine whether estimates of age for entering a stage of dental development in three early hominin fossils fell within the distribution of a modern human sample. This study used a comparative model of dental development to identify the stages of dental development most likely to provide information about length of the growth period in early fossil hominins. Age estimates for stages of dental development in fossils were superimposed onto a normal distribution of the same radiographically defined stages derived from a sample of 6540 children of diverse geographical origin. Both within the dentition of S7-37, from Sangiran, Java, but also for stages of two other specimens (KNM-WT 15000 from Kenya and StW 151 from South Africa), all age estimates for later stages of tooth formation fell within the modern sample range. A pattern appears to exist in early Homo where, both within and between developing dentitions, age estimates for stages of P4, M2 and M3 tooth formation fell consistently among the more advanced individuals of the modern human sample.

  3. Early Life on Earth: the Ancient Fossil Record

    Science.gov (United States)

    Westall, F.

    2004-07-01

    The evidence for early life and its initial evolution on Earth is lin= ked intimately with the geological evolution of the early Earth. The environment of the early Earth would be considered extreme by modern standards: hot (50-80=B0C), volcanically and hydrothermally active, a= noxic, high UV flux, and a high flux of extraterrestrial impacts. Habitats = for life were more limited until continent-building processes resulted in= the formation of stable cratons with wide, shallow, continental platforms= in the Mid-Late Archaean. Unfortunately there are no records of the first appearance of life and the earliest isotopic indications of the exist= ence of organisms fractionating carbon in ~3.8 Ga rocks from the Isua greenst= one belt in Greenland are tenuous. Well-preserved microfossils and micro= bial mats (in the form of tabular and domical stromatolites) occur in 3.5-= 3.3 Ga, Early Archaean, sedimentary formations from the Barberton (South Afri= ca) and Pilbara (Australia) greenstone belts. They document life forms that = show a relatively advanced level of evolution. Microfossil morphology inclu= des filamentous, coccoid, rod and vibroid shapes. Colonial microorganism= s formed biofilms and microbial mats at the surfaces of volcaniclastic = and chemical sediments, some of which created (small) macroscopic microbi= alites such as stromatolites. Anoxygenic photosynthesis may already have developed. Carbon, nitrogen and sulphur isotopes ratios are in the r= ange of those for organisms with anaerobic metabolisms, such as methanogenesi= s, sulphate reduction and photosynthesis. Life was apparently distribute= d widely in shallow-water to littoral environments, including exposed, evaporitic basins and regions of hydrothermal activity. Biomass in t= he early Archaean was restricted owing to the limited amount of energy t= hat could be produced by anaerobic metabolisms. Microfossils resembling o= xygenic photosynthesisers, such as cyanobacteria, probably first occurred in

  4. Early Cambrian phosphatized blastula-and gastrula-stage animal fossils from southern Shaanxi

    Institute of Scientific and Technical Information of China (English)

    HUA Hong; CHEN Zhe; ZHANG Luyi

    2004-01-01

    Marine invertebrate animal embryos and their early developmental products are of great significance to the study of taxonomy and phylogeny of early animals. A great number of phosphatized globular fossils were collected from the early Cambrian Kuanchuanpu Member (upper Dengying Formation), southern Shaanxi, and a nearly complete developmental sequence--from a fertilized egg, via blastodisc formation, blastula development, blastodisc enlargement toward gastrulae, to tissue differentiation--can be discerned in this collection. This discovery provides unmatchable material for studies on the origin, taxonomy, radiation,and ontogeny of early metazoans.

  5. Fossil traces of the bone-eating worm Osedax in early Oligocene whale bones.

    Science.gov (United States)

    Kiel, Steffen; Goedert, James L; Kahl, Wolf-Achim; Rouse, Greg W

    2010-05-11

    Osedax is a recently discovered group of siboglinid annelids that consume bones on the seafloor and whose evolutionary origins have been linked with Cretaceous marine reptiles or to the post-Cretaceous rise of whales. Here we present whale bones from early Oligocene bathyal sediments exposed in Washington State, which show traces similar to those made by Osedax today. The geologic age of these trace fossils ( approximately 30 million years) coincides with the first major radiation of whales, consistent with the hypothesis of an evolutionary link between Osedax and its main food source, although older fossils should certainly be studied. Osedax has been destroying bones for most of the evolutionary history of whales and the possible significance of this "Osedax effect" in relation to the quality and quantity of their fossils is only now recognized.

  6. Unlocking the early fossil record of the arthropod central nervous system

    Science.gov (United States)

    Edgecombe, Gregory D.; Ma, Xiaoya; Strausfeld, Nicholas J.

    2015-01-01

    Extant panarthropods (euarthropods, onychophorans and tardigrades) are hallmarked by stunning morphological and taxonomic diversity, but their central nervous systems (CNS) are relatively conserved. The timing of divergences of the ground pattern CNS organization of the major panarthropod clades has been poorly constrained because of a scarcity of data from their early fossil record. Although the CNS has been documented in three-dimensional detail in insects from Cenozoic ambers, it is widely assumed that these tissues are too prone to decay to withstand other styles of fossilization or geologically older preservation. However, Cambrian Burgess Shale-type compressions have emerged as sources of fossilized brains and nerve cords. CNS in these Cambrian fossils are preserved as carbon films or as iron oxides/hydroxides after pyrite in association with carbon. Experiments with carcasses compacted in fine-grained sediment depict preservation of neural tissue for a more prolonged temporal window than anticipated by decay experiments in other media. CNS and compound eye characters in exceptionally preserved Cambrian fossils predict divergences of the mandibulate and chelicerate ground patterns by Cambrian Stage 3 (ca 518 Ma), a dating that is compatible with molecular estimates for these splits. PMID:26554038

  7. Unlocking the early fossil record of the arthropod central nervous system.

    Science.gov (United States)

    Edgecombe, Gregory D; Ma, Xiaoya; Strausfeld, Nicholas J

    2015-12-19

    Extant panarthropods (euarthropods, onychophorans and tardigrades) are hallmarked by stunning morphological and taxonomic diversity, but their central nervous systems (CNS) are relatively conserved. The timing of divergences of the ground pattern CNS organization of the major panarthropod clades has been poorly constrained because of a scarcity of data from their early fossil record. Although the CNS has been documented in three-dimensional detail in insects from Cenozoic ambers, it is widely assumed that these tissues are too prone to decay to withstand other styles of fossilization or geologically older preservation. However, Cambrian Burgess Shale-type compressions have emerged as sources of fossilized brains and nerve cords. CNS in these Cambrian fossils are preserved as carbon films or as iron oxides/hydroxides after pyrite in association with carbon. Experiments with carcasses compacted in fine-grained sediment depict preservation of neural tissue for a more prolonged temporal window than anticipated by decay experiments in other media. CNS and compound eye characters in exceptionally preserved Cambrian fossils predict divergences of the mandibulate and chelicerate ground patterns by Cambrian Stage 3 (ca 518 Ma), a dating that is compatible with molecular estimates for these splits.

  8. In situ ∼2.0 Ma trees discovered as fossil rooted stumps, lowermost Bed I, Olduvai Gorge, Tanzania.

    Science.gov (United States)

    Habermann, Jörg M; Stanistreet, Ian G; Stollhofen, Harald; Albert, Rosa M; Bamford, Marion K; Pante, Michael C; Njau, Jackson K; Masao, Fidelis T

    2016-01-01

    The discovery of fossil rooted tree stumps in lowermost Lower Bed I from the western Olduvai Basin, Tanzania, age-bracketed by the Naabi Ignimbrite (2.038 ± 0.005 Ma) and Tuff IA (1.88 ± 0.05 Ma), provides the first direct, in situ, and to date oldest evidence of living trees at Olduvai Gorge. The tree relicts occur in an interval dominated by low-viscosity mass flow and braided fluvial sediments, deposited at the toe of a largely Ngorongoro Volcano-sourced volcaniclastic fan apron that comprised a widely spaced network of ephemeral braided streams draining northward into the Olduvai Basin. Preservation of the trees occurred through their engulfment by mass flows, post-mortem mold formation resulting from differential decay of woody tissues, and subsequent fluvially-related sediment infill, calcite precipitation, and cast formation. Rhizolith preservation was triggered by the interaction of root-induced organic and inorganic processes to form rhizocretionary calcareous root casts. Phytolith analyses were carried out to complete the paleoenvironmental reconstruction. They imply a pronounced seasonality and indicate a wooded landscape with grasses, shrubs, and sedges growing nearby, comparable to the low, open riverine woodland (unit 4c) along the Garusi River and tributaries in the Laetoli area. Among the tree stump cluster were found outsized lithic clasts and those consisting of quartzite were identified as Oldowan stone tool artifacts. In the context of hominin activity, the identification of wooded grassland in association with nearby freshwater drainages and Oldowan artifacts significantly extends our paleoenvironmental purview on the basal parts of Lower Bed I, and highlights the hitherto underrated role of the yet poorly explored western Olduvai Gorge area as a potential ecologically attractive setting and habitat for early hominins. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. A reappraisal of the stratigraphy and chronology of Early Pliocene palaeontological sites from Lanzarote Island containing fossil terrestrial animals

    Science.gov (United States)

    Lomoschitz, Alejandro; Sánchez Marco, Antonio; Huertas, María José; Betancort, Juan F.; Isern, Arnau; Sanz, Elena; Meco, Joaquín

    2016-11-01

    The Famara massif, in the north of Lanzarote Island, constitutes the remains of a former island inhabited by the oldest known vertebrate fauna of the Canary archipelago off the coast of Africa. In this study, new ages are offered for the underlying and overlying basaltic lava flows of two paleontological sites. The island's three major palaeontological sites, which contain remains of this ancient fauna (Valle Grande, Valle Chico and Fuente de Gusa), are intercorrelated according to their lithologies, sedimentology, palaeontological content and geochronology. The new K/Ar age interval for the fossiliferous sedimentary deposits ranges between 4.3 ± 0.7 and 3.78 ± 0.71 Ma, within the Early Pliocene, and shows that the first known terrestrial animals in Lanzarote were present on the island for about 500 ka. The principal component of the deposits is a bioclastic calcarenite of aeolian origin (sand sheet deposits), which is present in all three sites and constitutes 65% of the beds. The remaining 35% is of fluvial-aeolian origin (mainly stream deposits). All the beds contain the same fossils (insect egg pods, land snails, avian eggshells and tortoise eggshells). The local palaeogeography and the formation of the deposits were conditioned by a flat plain, larger than 16 km2, over which aeolian sands moved freely with a prevailing NNE-WSW wind direction. In agreement with previous investigations, the palaeoclimate in this interval (ca. 4.3 to 3.8 Ma) must have been mainly dry with some rainy episodes.

  10. Results concerning a clean co-combustion technology of waste biomass with fossil fuel, in a pilot fluidised bed combustion facility

    Energy Technology Data Exchange (ETDEWEB)

    Ionel, Ioana; Trif-Tordai, Gavril; Ungureanu, Corneliu; Popescu, Francisc; Lontis, Nicolae [Politehnica Univ. Timisoara (Romania). Faculty for Mechanical Engineering

    2008-07-01

    The research focuses on a facility, the experimental results, interpretation and future plans concerning a new developed technology of using waste renewable energy by applying the cocombustion of waste biomass with coal, in a fluidised bed system. The experimental facility is working entirely in accordance to the allowed limits for the exhaust flue gas concentration, with special concern for typical pollutants. The experiments conclude that the technology is cleaner, has as main advantage the possibility to reduce both the SO{sub 2} and CO{sub 2} exhaust in comparison to standard fossil fuel combustion, under comparable circumstances. The combustion is occurring in a stable fluidised bed. (orig.)

  11. New fossils from Koobi Fora in northern Kenya confirm taxonomic diversity in early Homo.

    Science.gov (United States)

    Leakey, Meave G; Spoor, Fred; Dean, M Christopher; Feibel, Craig S; Antón, Susan C; Kiarie, Christopher; Leakey, Louise N

    2012-08-09

    Since its discovery in 1972 (ref. 1), the cranium KNM-ER 1470 has been at the centre of the debate over the number of species of early Homo present in the early Pleistocene epoch of eastern Africa. KNM-ER 1470 stands out among other specimens attributed to early Homo because of its larger size, and its flat and subnasally orthognathic face with anteriorly placed maxillary zygomatic roots. This singular morphology and the incomplete preservation of the fossil have led to different views as to whether KNM-ER 1470 can be accommodated within a single species of early Homo that is highly variable because of sexual, geographical and temporal factors, or whether it provides evidence of species diversity marked by differences in cranial size and facial or masticatory adaptation. Here we report on three newly discovered fossils, aged between 1.78 and 1.95 million years (Myr) old, that clarify the anatomy and taxonomic status of KNM-ER 1470. KNM-ER 62000, a well-preserved face of a late juvenile hominin, closely resembles KNM-ER 1470 but is notably smaller. It preserves previously unknown morphology, including moderately sized, mesiodistally long postcanine teeth. The nearly complete mandible KNM-ER 60000 and mandibular fragment KNM-ER 62003 have a dental arcade that is short anteroposteriorly and flat across the front, with small incisors; these features are consistent with the arcade morphology of KNM-ER 1470 and KNM-ER 62000. The new fossils confirm the presence of two contemporary species of early Homo, in addition to Homo erectus, in the early Pleistocene of eastern Africa.

  12. The completeness of the fossil record of mesozoic birds: implications for early avian evolution.

    Directory of Open Access Journals (Sweden)

    Neil Brocklehurst

    Full Text Available Many palaeobiological analyses have concluded that modern birds (Neornithes radiated no earlier than the Maastrichtian, whereas molecular clock studies have argued for a much earlier origination. Here, we assess the quality of the fossil record of Mesozoic avian species, using a recently proposed character completeness metric which calculates the percentage of phylogenetic characters that can be scored for each taxon. Estimates of fossil record quality are plotted against geological time and compared to estimates of species level diversity, sea level, and depositional environment. Geographical controls on the avian fossil record are investigated by comparing the completeness scores of species in different continental regions and latitudinal bins. Avian fossil record quality varies greatly with peaks during the Tithonian-early Berriasian, Aptian, and Coniacian-Santonian, and troughs during the Albian-Turonian and the Maastrichtian. The completeness metric correlates more strongly with a 'sampling corrected' residual diversity curve of avian species than with the raw taxic diversity curve, suggesting that the abundance and diversity of birds might influence the probability of high quality specimens being preserved. There is no correlation between avian completeness and sea level, the number of fluviolacustrine localities or a recently constructed character completeness metric of sauropodomorph dinosaurs. Comparisons between the completeness of Mesozoic birds and sauropodomorphs suggest that small delicate vertebrate skeletons are more easily destroyed by taphonomic processes, but more easily preserved whole. Lagerstätten deposits might therefore have a stronger impact on reconstructions of diversity of smaller organisms relative to more robust forms. The relatively poor quality of the avian fossil record in the Late Cretaceous combined with very patchy regional sampling means that it is possible neornithine lineages were present throughout this

  13. Terrestrial origin of viviparity in mesozoic marine reptiles indicated by early triassic embryonic fossils.

    Science.gov (United States)

    Motani, Ryosuke; Jiang, Da-yong; Tintori, Andrea; Rieppel, Olivier; Chen, Guan-bao

    2014-01-01

    Viviparity in Mesozoic marine reptiles has traditionally been considered an aquatic adaptation. We report a new fossil specimen that strongly contradicts this traditional interpretation. The new specimen contains the oldest fossil embryos of Mesozoic marine reptile that are about 10 million years older than previous such records. The fossil belongs to Chaohusaurus (Reptilia, Ichthyopterygia), which is the oldest of Mesozoic marine reptiles (ca. 248 million years ago, Early Triassic). This exceptional specimen captures an articulated embryo in birth position, with its skull just emerged from the maternal pelvis. Its headfirst birth posture, which is unlikely to be a breech condition, strongly indicates a terrestrial origin of viviparity, in contrast to the traditional view. The tail-first birth posture in derived ichthyopterygians, convergent with the conditions in whales and sea cows, therefore is a secondary feature. The unequivocally marine origin of viviparity is so far not known among amniotes, a subset of vertebrate animals comprising mammals and reptiles, including birds. Therefore, obligate marine amniotes appear to have evolved almost exclusively from viviparous land ancestors. Viviparous land reptiles most likely appeared much earlier than currently thought, at least as early as the recovery phase from the end-Permian mass extinction.

  14. Terrestrial origin of viviparity in mesozoic marine reptiles indicated by early triassic embryonic fossils.

    Directory of Open Access Journals (Sweden)

    Ryosuke Motani

    Full Text Available Viviparity in Mesozoic marine reptiles has traditionally been considered an aquatic adaptation. We report a new fossil specimen that strongly contradicts this traditional interpretation. The new specimen contains the oldest fossil embryos of Mesozoic marine reptile that are about 10 million years older than previous such records. The fossil belongs to Chaohusaurus (Reptilia, Ichthyopterygia, which is the oldest of Mesozoic marine reptiles (ca. 248 million years ago, Early Triassic. This exceptional specimen captures an articulated embryo in birth position, with its skull just emerged from the maternal pelvis. Its headfirst birth posture, which is unlikely to be a breech condition, strongly indicates a terrestrial origin of viviparity, in contrast to the traditional view. The tail-first birth posture in derived ichthyopterygians, convergent with the conditions in whales and sea cows, therefore is a secondary feature. The unequivocally marine origin of viviparity is so far not known among amniotes, a subset of vertebrate animals comprising mammals and reptiles, including birds. Therefore, obligate marine amniotes appear to have evolved almost exclusively from viviparous land ancestors. Viviparous land reptiles most likely appeared much earlier than currently thought, at least as early as the recovery phase from the end-Permian mass extinction.

  15. Early Eocene fossils suggest that the mammalian order Perissodactyla originated in India.

    Science.gov (United States)

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

    2014-11-20

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

  16. Homo floresiensis-like fossils from the early Middle Pleistocene of Flores.

    Science.gov (United States)

    van den Bergh, Gerrit D; Kaifu, Yousuke; Kurniawan, Iwan; Kono, Reiko T; Brumm, Adam; Setiyabudi, Erick; Aziz, Fachroel; Morwood, Michael J

    2016-06-09

    The evolutionary origin of Homo floresiensis, a diminutive hominin species previously known only by skeletal remains from Liang Bua in western Flores, Indonesia, has been intensively debated. It is a matter of controversy whether this primitive form, dated to the Late Pleistocene, evolved from early Asian Homo erectus and represents a unique and striking case of evolutionary reversal in hominin body and brain size within an insular environment. The alternative hypothesis is that H. floresiensis derived from an older, smaller-brained member of our genus, such as Homo habilis, or perhaps even late Australopithecus, signalling a hitherto undocumented dispersal of hominins from Africa into eastern Asia by two million years ago (2 Ma). Here we describe hominin fossils excavated in 2014 from an early Middle Pleistocene site (Mata Menge) in the So'a Basin of central Flores. These specimens comprise a mandible fragment and six isolated teeth belonging to at least three small-jawed and small-toothed individuals. Dating to ~0.7 Ma, these fossils now constitute the oldest hominin remains from Flores. The Mata Menge mandible and teeth are similar in dimensions and morphological characteristics to those of H. floresiensis from Liang Bua. The exception is the mandibular first molar, which retains a more primitive condition. Notably, the Mata Menge mandible and molar are even smaller in size than those of the two existing H. floresiensis individuals from Liang Bua. The Mata Menge fossils are derived compared with Australopithecus and H. habilis, and so tend to support the view that H. floresiensis is a dwarfed descendent of early Asian H. erectus. Our findings suggest that hominins on Flores had acquired extremely small body size and other morphological traits specific to H. floresiensis at an unexpectedly early time.

  17. Leaf economic traits from fossils support a weedy habit for early angiosperms.

    Science.gov (United States)

    Royer, Dana L; Miller, Ian M; Peppe, Daniel J; Hickey, Leo J

    2010-03-01

    Many key aspects of early angiosperms are poorly known, including their ecophysiology and associated habitats. Evidence for fast-growing, weedy angiosperms comes from the Early Cretaceous Potomac Group, where angiosperm fossils, some of them putative herbs, are found in riparian depositional settings. However, inferences of growth rate from sedimentology and growth habit are somewhat indirect; also, the geographic extent of a weedy habit in early angiosperms is poorly constrained. Using a power law between petiole width and leaf mass, we estimated the leaf mass per area (LMA) of species from three Albian (110-105 Ma) fossil floras from North America (Winthrop Formation, Patapsco Formation of the Potomac Group, and the Aspen Shale). All LMAs for angiosperm species are low (240 g/m(2); mean = 291 g/m(2)). On the basis of extant relationships between LMA and other leaf economic traits such as photosynthetic rate and leaf lifespan, we conclude that these Early Cretaceous landscapes were populated with weedy angiosperms with short-lived leaves (success.

  18. Pyrite framboids associated with the Mesozoic Jehol Biota in northeastern China: Implications for microenvironment during early fossilization

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Despite of the recent influx of reports describing important fossil specimens from the Mesozoic Jehol Biota, detailed information on the mechanism of fossilization and paleoenvironment in which these fossils were deposited is scanty. We present an analysis of microenvironment based upon scanning electron microscope observations of in situ pyrite framboids and microcrystallines of plant and vertebrate feather fossils in the Jehol Biota. Pyrite microcrystallines and framboids occur extensively inside and on surface of plant fossils.Framboids found on feathers and in sedimentary matrix were in a lower abundance. These framboids have diameters ranging from 6 μm to 31 μm with an average of 20 μm, indicating a dysoxic aqueous condition with free oxygen level less than 30 μmol/L for the microenvironment where these framboids were formed. The outgrowth of framboids inside plant tissues suggests the presence of water molecules and free oxygen at the cellular level during pyritization; the relative timing between tissue decay and framboid formation implies a rapid tissue degradation occurred during the very early stage of fossilization. This line of reasoning is consistent with the observation that cell level structure of plant fossils from these deposits is rarely preserved. We propose a "fossil envelop" model to accommodate the different geochemical conditions between the microenvironment surrounding the fossil material and the macroenvironment of background lake bottom water.

  19. A total-evidence approach to dating with fossils, applied to the early radiation of the hymenoptera.

    Science.gov (United States)

    Ronquist, Fredrik; Klopfstein, Seraina; Vilhelmsen, Lars; Schulmeister, Susanne; Murray, Debra L; Rasnitsyn, Alexandr P

    2012-12-01

    Phylogenies are usually dated by calibrating interior nodes against the fossil record. This relies on indirect methods that, in the worst case, misrepresent the fossil information. Here, we contrast such node dating with an approach that includes fossils along with the extant taxa in a Bayesian total-evidence analysis. As a test case, we focus on the early radiation of the Hymenoptera, mostly documented by poorly preserved impression fossils that are difficult to place phylogenetically. Specifically, we compare node dating using nine calibration points derived from the fossil record with total-evidence dating based on 343 morphological characters scored for 45 fossil (4--20 complete) and 68 extant taxa. In both cases we use molecular data from seven markers (∼5 kb) for the extant taxa. Because it is difficult to model speciation, extinction, sampling, and fossil preservation realistically, we develop a simple uniform prior for clock trees with fossils, and we use relaxed clock models to accommodate rate variation across the tree. Despite considerable uncertainty in the placement of most fossils, we find that they contribute significantly to the estimation of divergence times in the total-evidence analysis. In particular, the posterior distributions on divergence times are less sensitive to prior assumptions and tend to be more precise than in node dating. The total-evidence analysis also shows that four of the seven Hymenoptera calibration points used in node dating are likely to be based on erroneous or doubtful assumptions about the fossil placement. With respect to the early radiation of Hymenoptera, our results suggest that the crown group dates back to the Carboniferous, ∼309 Ma (95% interval: 291--347 Ma), and diversified into major extant lineages much earlier than previously thought, well before the Triassic. [Bayesian inference; fossil dating; morphological evolution; relaxed clock; statistical phylogenetics.].

  20. Paleoclimate from fossil plants and application to the early Cenozoic Rocky Mountains

    Science.gov (United States)

    Wing, S. L.

    2011-12-01

    Wladimir Köppen called vegetation "crystallized, visible climate," and his metaphor encouraged paleobotanists to climb the chain of inference from fossil plants to paleovegetation to paleoclimate. Inferring paleovegetation from fossils has turned out to be very difficult, however, and today most paleobotanical methods for inferring paleoclimate do not try to reconstruct paleovegetation as a first step. Three major approaches are widely use to infer paleoclimate from plant fossils: 1) phylogenetic inferences rely on the climatic distributions of extant relatives of fossils, 2) morphological inferences use present-day correlations of climate with plant morphology (e.g, leaf shape, wood anatomy), and 3) chemical inferences rely on correlations between climate and the stable isotopic composition of plants or organic compounds. Each approach makes assumptions that are hard to verify. Phylogenetic inference depends on accurate identification of fossils, and also assumes that evolution and/or extinction has not shifted the climatic distributions of plant lineages through time. On average this assumption is less valid for older time periods, but probably it is not radically wrong for the early Cenozoic. Morphological approaches don't require taxonomic identification of plant fossils, but do assume that correlations between plant form and climate have been constant over time. This assumption is bolstered if the ecophysiological cause of the morphology-climate correlation is well understood, but often it isn't. Stable isotopic approaches assume that present-day correlations between isotopic composition and climate apply to the past. Commonly the chemical and physiological mechanisms responsible for the correlation are moderately well known, but often the variation among different taxonomic and functional groups of plants is poorly characterized. In spite of limitations and uncertainties on all methods for inferring paleoclimate from fossil plants, broad patterns emerge from

  1. First discovery of colobine fossils from the Late Miocene/Early Pliocene in central Myanmar.

    Science.gov (United States)

    Takai, Masanaru; Thaung-Htike; Zin-Maung-Maung-Thein; Soe, Aung Naing; Maung, Maung; Tsubamoto, Takehisa; Egi, Naoko; Nishimura, Takeshi D; Nishioka, Yuichiro

    2015-07-01

    Here we report two kinds of colobine fossils discovered from the latest Miocene/Early Pliocene Irrawaddy sediments of the Chaingzauk area, central Myanmar. A left mandibular corpus fragment preserving M1-3 is named as a new genus and species, Myanmarcolobus yawensis. Isolated upper (M(1)?) and lower (M2) molars are tentatively identified as Colobinae gen. et sp. indet. Although both forms are medium-sized colobines, they are quite different from each other in M2 morphology. The isolated teeth of the latter show typical colobine-type features, so it is difficult to identify their taxonomic position, whereas lower molars of Myanmarcolobus have unique features, such as a trapezoid-shaped long median lingual notch, a deeply concave median buccal cleft, a strongly developed mesiobuccal notch, and rather obliquely running transverse lophids. Compared with fossil and living Eurasian colobine genera, Myanmarcolobus is most similar in lower molar morphology to the Pliocene Dolichopithecus of Europe rather than to any Asian forms. In Dolichopithecus, however, the tooth size is much larger and the median lingual notch is mesiodistally much shorter than that of Myanmarcolobus. The discovery of Myanmarcolobus in central Myanmar is the oldest fossil record in Southeast Asia not only of colobine but also of cercopithecid monkeys and raises many questions regarding the evolutionary history of Asian colobine monkeys.

  2. First North American fossil monkey and early Miocene tropical biotic interchange

    Science.gov (United States)

    Bloch, Jonathan I.; Woodruff, Emily D.; Wood, Aaron R.; Rincon, Aldo F.; Harrington, Arianna R.; Morgan, Gary S.; Foster, David A.; Montes, Camilo; Jaramillo, Carlos A.; Jud, Nathan A.; Jones, Douglas S.; MacFadden, Bruce J.

    2016-05-01

    New World monkeys (platyrrhines) are a diverse part of modern tropical ecosystems in North and South America, yet their early evolutionary history in the tropics is largely unknown. Molecular divergence estimates suggest that primates arrived in tropical Central America, the southern-most extent of the North American landmass, with several dispersals from South America starting with the emergence of the Isthmus of Panama 3-4 million years ago (Ma). The complete absence of primate fossils from Central America has, however, limited our understanding of their history in the New World. Here we present the first description of a fossil monkey recovered from the North American landmass, the oldest known crown platyrrhine, from a precisely dated 20.9-Ma layer in the Las Cascadas Formation in the Panama Canal Basin, Panama. This discovery suggests that family-level diversification of extant New World monkeys occurred in the tropics, with new divergence estimates for Cebidae between 22 and 25 Ma, and provides the oldest fossil evidence for mammalian interchange between South and North America. The timing is consistent with recent tectonic reconstructions of a relatively narrow Central American Seaway in the early Miocene epoch, coincident with over-water dispersals inferred for many other groups of animals and plants. Discovery of an early Miocene primate in Panama provides evidence for a circum-Caribbean tropical distribution of New World monkeys by this time, with ocean barriers not wholly restricting their northward movements, requiring a complex set of ecological factors to explain their absence in well-sampled similarly aged localities at higher latitudes of North America.

  3. Early organisms in the fossil record: paleontological aspects, evolutionary and ecological impacts

    Science.gov (United States)

    Sabbatini, Anna; Negri, Alessandra; Morigi, Caterina; Bartolini, Annachiara; Lipps, Jere

    2017-04-01

    With this abstract we introduce our session whose aim is twofold: 1) to gather information on the earliest foraminifera (single- organic and agglutinated taxa) which so far are sparse and uncoordinated in order to understand their evolution and their relationship with modern single-chambered taxa, contextualizing scientific current results in the geo-biological field. 2) to explore also every other early organism trace fossils or so far overlooked organisms coated with fine sediment (i.e., bacteria, testate amoebae) to understand how and if this coating might help these creatures to fossilize. For this reason, this session will integrate many disciplines, from genomics to palaeo-environmental modelling to palaeontology and geochemistry. Our experience starts from Foraminifera which are an ecologically important group of modern heterotrophic amoeboid eukaryotes whose naked and testate ancestors are thought to have evolved 1 Ga ago. However, the single-chambered agglutinated test of these protists is hypothesized to appear in the fossil record in the Neoproterozoic, before the rise of complex animals. In addition, the difficulty of recognizing unambiguously ancestral monothalamous foraminifera in the fossil record represents the main challenge and might be related to a combination of factors, such as preservation in the sediments, adverse palaeo-environmental conditions and the absence of clear morphological characters distinguishing them from other morphologically simple testate organisms. However, recent publications have evidenced the finding of such organisms in several sedimentary successions tracing back to the Neoproterozoic. An integrate approach will result in profound insights about life—past, present, future— representing a new frontier in the palaeobiological studies. Therefore, aim of this session is to bring together specialists across all these disciplines to provide a uniquely rich and fertile intellectual environment for the pursuit of this

  4. Calcification and Silicification: Fossilization Potential of Cyanobacteria from Stromatolites of Niuafo‘ou's Caldera Lakes (Tonga) and Implications for the Early Fossil Record

    Science.gov (United States)

    Kazmierczak, Józef; Łukomska-Kowalczyk, Maja; Kempe, Stephan

    2012-01-01

    Abstract Calcification and silicification processes of cyanobacterial mats that form stromatolites in two caldera lakes of Niuafo‘ou Island (Vai Lahi and Vai Si‘i) were evaluated, and their importance as analogues for interpreting the early fossil record are discussed. It has been shown that the potential for morphological preservation of Niuafo‘ou cyanobacteria is highly dependent on the timing and type of mineral phase involved in the fossilization process. Four main modes of mineralization of cyanobacteria organic parts have been recognized: (i) primary early postmortem calcification by aragonite nanograins that transform quickly into larger needle-like crystals and almost totally destroy the cellular structures, (ii) primary early postmortem silicification of almost intact cyanobacterial cells that leave a record of spectacularly well-preserved cellular structures, (iii) replacement by silica of primary aragonite that has already recrystallized and obliterated the cellular structures, (iv) occasional replacement of primary aragonite precipitated in the mucopolysaccharide sheaths and extracellular polymeric substances by Al-Mg-Fe silicates. These observations suggest that the extremely scarce earliest fossil record may, in part, be the result of (a) secondary replacement by silica of primary carbonate minerals (aragonite, calcite, siderite), which, due to recrystallization, had already annihilated the cellular morphology of the mineralized microbiota or (b) relatively late primary silicification of already highly degraded and no longer morphologically identifiable microbial remains. Key Words: Stromatolites—Cyanobacteria—Calcification—Silicification—Niuafo‘ou (Tonga)—Archean. Astrobiology 12, 535–548. PMID:22794297

  5. Calcification and silicification: fossilization potential of cyanobacteria from stromatolites of Niuafo'ou's Caldera Lakes (Tonga) and implications for the early fossil record.

    Science.gov (United States)

    Kremer, Barbara; Kazmierczak, Józef; Lukomska-Kowalczyk, Maja; Kempe, Stephan

    2012-06-01

    Calcification and silicification processes of cyanobacterial mats that form stromatolites in two caldera lakes of Niuafo'ou Island (Vai Lahi and Vai Si'i) were evaluated, and their importance as analogues for interpreting the early fossil record are discussed. It has been shown that the potential for morphological preservation of Niuafo'ou cyanobacteria is highly dependent on the timing and type of mineral phase involved in the fossilization process. Four main modes of mineralization of cyanobacteria organic parts have been recognized: (i) primary early postmortem calcification by aragonite nanograins that transform quickly into larger needle-like crystals and almost totally destroy the cellular structures, (ii) primary early postmortem silicification of almost intact cyanobacterial cells that leave a record of spectacularly well-preserved cellular structures, (iii) replacement by silica of primary aragonite that has already recrystallized and obliterated the cellular structures, (iv) occasional replacement of primary aragonite precipitated in the mucopolysaccharide sheaths and extracellular polymeric substances by Al-Mg-Fe silicates. These observations suggest that the extremely scarce earliest fossil record may, in part, be the result of (a) secondary replacement by silica of primary carbonate minerals (aragonite, calcite, siderite), which, due to recrystallization, had already annihilated the cellular morphology of the mineralized microbiota or (b) relatively late primary silicification of already highly degraded and no longer morphologically identifiable microbial remains.

  6. New hominin fossils from Kanapoi, Kenya, and the mosaic evolution of canine teeth in early hominins

    Directory of Open Access Journals (Sweden)

    J. Michael Plavcan

    2012-03-01

    Full Text Available Whilst reduced size, altered shape and diminished sexual dimorphism of the canine–premolar complex are diagnostic features of the hominin clade, little is known about the rate and timing of changes in canine size and shape in early hominins. The earliest Australopithecus, Australopithecus anamensis, had canine crowns similar in size to those of its descendant Australopithecus afarensis, but a single large root alveolus has suggested that this species may have had larger and more dimorphic canines than previously recognised. Here we present three new associated dentitions attributed to A. anamensis, recently recovered from the type site of Kanapoi, Kenya, that provide evidence of canine evolution in early Australopithecus. These fossils include the largest mandibular canine root in the hominin fossil record. We demonstrate that, although canine crown height did not differ between these species, A. anamensis had larger and more dimorphic roots, more like those of extant great apes and Ardipithecus ramidus, than those of A. afarensis. The canine and premolar occlusal shapes of A. anamensis also resemble those of Ar. ramidus, and are intermediary between extant great apes and A. afarensis. A. afarensis achieved Homo-like maxillary crown basal proportions without a reduction in crown height. Thus, canine crown size and dimorphism remained stable during the early evolution of Australopithecus, but mandibular root dimensions changed only later within the A. anamensis–afarensis lineage, coincident with morphological changes in the canine–premolar complex. These observations suggest that selection on canine tooth crown height, shape and root dimensions was not coupled in early hominin evolution, and was not part of an integrated adaptive package.

  7. The use of cusum analysis in the early detection and management of hospital bed occupancy crises.

    Science.gov (United States)

    Burns, Claire M; Bennett, Cameron J; Myers, Colin T; Ward, Michael

    2005-09-19

    To assess the value of cusum analysis in hospital bed management. Comparative analysis of medical patient flows, bed occupancy, and emergency department admission rates and access block over 2 years. Internal Medicine Services and Emergency Department in a teaching hospital. Improvements in bed use and changes in the level of available beds. Average length of stay; percentage occupancy of available beds; number of patients waiting more than 8 hours for admission (access block); number of medical patients occupying beds in non-medical wards; and number of elective surgical admissions. Cusum analysis provided a simple means of revealing important trends in patient flows that were not obvious in conventional time-series data. This prompted improvements in bed use that resulted in a decrease of 9500 occupied bed-days over a year. Unfortunately and unexpectedly, after some initial improvement, the levels of access block, medical ward congestion and elective surgical admissions all then deteriorated significantly. This was probably caused by excessive bed closures in response to the initial improvement in bed use. Cusum analysis is a useful technique for the early detection of significant changes in patient flows and bed use, and in determining the appropriate number of beds required for a given rate of patient flow.

  8. Early motion in a rapidly decompressed particle bed

    Science.gov (United States)

    Zunino, Heather; Adrian, Ronald; Clarke, Amanda

    2016-11-01

    Rapid expansion of dense, pressurized beds of fine particles subjected to rapid reduction of the external pressure is studied in a vertical shock tube. Located at bottom of a high pressure chamber below the shock tube diaphragm, a particle bed expands when the diaphragm bursts, releasing a near-sonic expansion wave that impinges on the particle bed-gas interface. The expansion wave presents a very rapid unloading to the particle bed. A high-speed video camera and pressure sensors capture events occurring during bed expansion. Interesting structures during the first few milliseconds include two-dimensional instabilities of the particle bed's surface and roughly spatially periodic regions void of particles within the bed. One-dimensional and two-dimensional Fourier analyses are used to measure their frequencies in space-time. It is found that the frequencies and patterns exhibit a clear dependence on particle diameter in which cell frequency decreases and cell size increases with increasing particle size. This work is supported by the U.S. Department of Energy, National Nuclear Security Administration, Advanced Simulation and Computing Program, as a Cooperative Agreement under the Predictive Science and Academic Alliance Program, under Contract No. DE-NA0002378.

  9. Stratigraphic implications of Sinian-Early Cambrian volcanic ash beds on the Yangtze Platform

    Institute of Scientific and Technical Information of China (English)

    ZHANG Junming; ZHU Maoyan; YANG Aihua; LI Guoxiang; YANG Jinghong; Christoph HEUBECK

    2004-01-01

    Volcanic ash beds from shallow- to deep-water facies strata of the Sinian-Early Cambrian (Meishucunian) on the Yangtze Platform consist of bentonites and tuffites which are readily recognized in the field by their physical features and confirmed by geochemical analyses.Geochemistry suggests that the volcanic ash beds in Meishucunian time are rhyolite and rhyodacite while those in the Qiongzhusian and Sinian are andesite and trachyandesite.The ash beds in the time-equivalent strata, even in different areas display rather similar geochemical features, whereas the ash beds in different strata even in the same areas show large chemical difference.The results suggest that these ash beds can be used for intra- and extra-basinal correlations of the Sinian-Early Cambrian interval on the Yangtze Platform.Additionally, these ash beds suggest high potentials for further U-Pb dating strategies.

  10. Carbon isotopic composition of fossil leaves from the Early Cretaceous sediments of western India

    Indian Academy of Sciences (India)

    S Chakraborty; B N Jana; S K Bhattacharya; I Robertson

    2011-08-01

    Stable carbon isotope analysis of fossil leaves from the Bhuj Formation, western India was carried out to infer the prevailing environmental conditions. Compression fossil leaves such as Pachypteris indica, Otozamite kachchhensis, Brachyphyllum royii and Dictyozamites sp. were recovered from three sedimentary successions of the Bhuj Formation, Early Cretaceous in age. A chronology was established based on faunal assemblage and palyno-stratigraphy and further constrained by carbon isotope stratigraphy. The three sampling sites were the Karawadi river bank near Dharesi; the Chawad river bank near Mathal; and the Pur river section near Trambau village in Gujarat. The Dharesi sample was also analyzed to investigate intra-leaf 13C variability. The mean 13C of the leaf was −24.6 ± 0.4‰ which implied negligible systematic change along the leaf axis. The Mathal sample was fragmented in nature and showed considerable variation in carbon isotopic composition. The Trambau sample considered to be the oldest, dating to the middle of Aptian (ca. 116 Ma), shows the most depleted value in 13C among all of them. The overall 13C trend ranging from mid Aptian (ca. 116 Ma) to early Albian (ca. 110 Ma) shows a progressive increase in 13C from −26.8 to −20.5‰. Based on these measurements the carbon isotopic composition of atmospheric carbon dioxide of the Aptian–Albian period is estimated to be between −7.4 and −1.7‰. The ratio of the partial pressure of carbon dioxide in leaf to that of the ambient atmosphere calculated based on a model is estimated to be similar to that of the modern plants. This indicates that the Early-Cretaceous plants adapted to the prevailing high carbon dioxide regime by increasing their photosynthetic uptake.

  11. A kind of coccoid dinoflagel-lates-like fossils gives a new explanation of source of dinosterane in the Early- Middle Cambrian

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The coccoid fossils covered with thick gelatinous envelop containing several gametes are discovered in gyps and salt deposits of Cambrian, H4 well and chert bed of the base of Yuertus Formation (∈11) of Xiaoerbulake Section. The fossils are described and compared with coccoid dino-flagellates. These fossils may be a coccoid life-cycle stage (vegetative cyst) of coccoid dinoflagellates. If this identifica-tion is correct, the coccoid dinoflagellates-like fossils could give a reasonable explanation of the dinoflagellate-specific biomarkers from Cambrian, H4 well, Tarim Basin.

  12. Bryophyte-like Fossil (Parafunaria sinensis) from Early-Middle Cambrian Kaili Formation in Guizhou Province, China

    Institute of Scientific and Technical Information of China (English)

    YANGRui-Dong; MAOJia-Rer; ZHANGWei-Hua; JIANGLi-Jun; GAOHui

    2004-01-01

    Abundant well-preserved animal and macroalgal fossils were discovered in the Early-MiddleCambrian Kaili Formation of Taijiang County, Guizhou Province, China, which constitute the Kaili Biota,named as one of the three important Burgess Shale-type faunas. The bryophyte-like fossil (Parafunariasinensis Yang gen. et sp. nov) was discovered in the horizon of occurrence of Macroalgal fossils. The fossilof P. sinensis possesses typical characters of bryophyte, such as whorled leaves, capsule and seta, andcomplex rhizoid or foot. We infer that the bryophyte-like fossil could be the ancestor of bryophyte. Thediscovery provides a new lead for further study on the origin and evolution of bryophyte or land plant.

  13. Early stage biomineralization in the periostracum of the 'living fossil' bivalve Neotrigonia.

    Directory of Open Access Journals (Sweden)

    Antonio G Checa

    Full Text Available A detailed investigation of the shell formation of the palaeoheterodont 'living fossil' Neotrigonia concentrated on the timing and manufacture of the calcified 'bosses' which stud the outside of all trigonioid bivalves (extant and fossil has been conducted. Electron microscopy and optical microscopy revealed that Neotrigonia spp. have a spiral-shaped periostracal groove. The periostracum itself is secreted by the basal cell, as a thin dark pellicle, becoming progressively transformed into a thin dark layer by additions of secretions from the internal outer mantle fold. Later, intense secretion of the internal surface of the outer mantle fold forms a translucent layer, which becomes transformed by tanning into a dark layer. The initiation of calcified bosses occurred at a very early stage of periostracum formation, deep within the periostracal groove immediately below the initialmost dark layer. At this stage, they consist of a series of polycyclically twinned crystals. The bosses grow as the periostracum traverse through the periostracal groove, in coordination with the thickening of the dark periostracal layer and until, upon reaching the mantle edge, they impinge upon each other and become transformed into large prisms separated by dark periostracal walls. In conclusion, the initial bosses and the external part of the prismatic layer are fully intraperiostracal. With later growth, the prisms transform into fibrous aggregates, although the details of the process are unknown. This reinforces the relationships with other groups that have the ability to form intraperiostracal calcifications, for example the unionoids with which the trigonioids form the clade Paleoheterodonta. The presence of similar structures in anomalodesmatans and other euheterodonts raises the question of whether this indicates a relationship or represents a convergence. The identification of very early calcification within an organic sheet has interesting implications for our

  14. Early stage biomineralization in the periostracum of the 'living fossil' bivalve Neotrigonia.

    Science.gov (United States)

    Checa, Antonio G; Salas, Carmen; Harper, Elizabeth M; Bueno-Pérez, Juan de Dios

    2014-01-01

    A detailed investigation of the shell formation of the palaeoheterodont 'living fossil' Neotrigonia concentrated on the timing and manufacture of the calcified 'bosses' which stud the outside of all trigonioid bivalves (extant and fossil) has been conducted. Electron microscopy and optical microscopy revealed that Neotrigonia spp. have a spiral-shaped periostracal groove. The periostracum itself is secreted by the basal cell, as a thin dark pellicle, becoming progressively transformed into a thin dark layer by additions of secretions from the internal outer mantle fold. Later, intense secretion of the internal surface of the outer mantle fold forms a translucent layer, which becomes transformed by tanning into a dark layer. The initiation of calcified bosses occurred at a very early stage of periostracum formation, deep within the periostracal groove immediately below the initialmost dark layer. At this stage, they consist of a series of polycyclically twinned crystals. The bosses grow as the periostracum traverse through the periostracal groove, in coordination with the thickening of the dark periostracal layer and until, upon reaching the mantle edge, they impinge upon each other and become transformed into large prisms separated by dark periostracal walls. In conclusion, the initial bosses and the external part of the prismatic layer are fully intraperiostracal. With later growth, the prisms transform into fibrous aggregates, although the details of the process are unknown. This reinforces the relationships with other groups that have the ability to form intraperiostracal calcifications, for example the unionoids with which the trigonioids form the clade Paleoheterodonta. The presence of similar structures in anomalodesmatans and other euheterodonts raises the question of whether this indicates a relationship or represents a convergence. The identification of very early calcification within an organic sheet has interesting implications for our understanding of

  15. Paleomagnetism of red beds of Early Devonian age from Central Iran

    NARCIS (Netherlands)

    Wensink, H.

    1983-01-01

    Paleomagnetic results are reported from 13 sites of red beds of Early Devonian age from Central Iran. Detailed paleomagnetic analyses were carried out. Two types of partial progressive demagnetization were applied, one using alternating magnetic fields, the other heating.

  16. A New Fossil Termite(Isoptera,Stolotermitidae,Stolotermes)from the Early Miocene of Otago,New Zealand

    Institute of Scientific and Technical Information of China (English)

    Uwe KAULFUSS; Anthony C.HARRIS; Daphne E.LEE

    2010-01-01

    The forewing of a termite from Eady Miocene lake sediments in Otago,southern New Zealand is figured and described.It exhibits the generic characters of the damp-wood termite Stolotermes Hagen,but differs from forewings of the known species in size and venation pattern and is described as Stolotermes kupe sp.nov.S.kupe represents the first confident record of fossil Stolotermitidae and extends the fossil record of the family back to the Early Miocene.It also is the first direct evidence of fossil Isoptera from New Zealand.though silicified termite faecal pellets.referable to Kalotermes brauni,have been previously described.S.kupe indicates that Stolotermitidae has been present in the Australasian re#on since at least the Early Miocene.

  17. Improved age control on early Homo fossils from the upper Burgi Member at Koobi Fora, Kenya.

    Science.gov (United States)

    Joordens, Josephine C A; Dupont-Nivet, Guillaume; Feibel, Craig S; Spoor, Fred; Sier, Mark J; van der Lubbe, Jeroen H J L; Nielsen, Trine Kellberg; Knul, Monika V; Davies, Gareth R; Vonhof, Hubert B

    2013-12-01

    To address questions regarding the evolutionary origin, radiation and dispersal of the genus Homo, it is crucial to be able to place the occurrence of hominin fossils in a high-resolution chronological framework. The period around 2 Ma (millions of years ago) in eastern Africa is of particular interest as it is at this time that a more substantial fossil record of the genus Homo is first found. Here we combine magnetostratigraphy and strontium (Sr) isotope stratigraphy to improve age control on hominin-bearing upper Burgi (UBU) deposits in Areas 105 and 131 on the Karari Ridge in the eastern Turkana Basin (Kenya). We identify the base of the Olduvai subchron (bC2n) plus a short isolated interval of consistently normal polarity that we interpret to be the Pre-Olduvai event. Combined with precession-forced (~20 kyr [thousands of years]) wet-dry climate cycles resolved by Sr isotope ratios, the magnetostratigraphic data allow us to construct an age model for the UBU deposits. We provide detailed age constraints for 15 hominin fossils from Area 131, showing that key specimens such as cranium KNM-ER 1470, partial face KNM-ER 62000 and mandibles KNM-ER 1482, KNM-ER 1801, and KNM-ER 1802 can be constrained between 1.945 ± 0.004 and 2.058 ± 0.034 Ma, and thus older than previously estimated. The new ages are consistent with a temporal overlap of two species of early Homo that can be distinguished by their facial morphology. Further, our results show that in this time interval, hominins occurred throughout the wet-dry climate cycles, supporting the hypothesis that the lacustrine Turkana Basin was a refugium during regionally dry periods. By establishing the observed first appearance datum of a marine-derived stingray in UBU deposits at 2.058 ± 0.034 Ma, we show that at this time the Turkana Basin was hydrographically connected to the Indian Ocean, facilitating dispersal of fauna between these areas. From a biogeographical perspective, we propose that the Indian Ocean

  18. Early Miocene Nothofagus in Antarctica based on fossil leaves from the Transantarctic Mountains

    Science.gov (United States)

    Wrobleski, S. A.; Ashworth, A. C.; Lewis, A. R.

    2014-12-01

    Nothofagus (Southern Beech) is the most widely reported plant from Cenozoic Antarctic fossil assemblages. Most of the fossils are of pollen morphotypes and it is assumed that the plants the pollen represents were growing on the continent. However, because of the uncertainties with systematics, long-distance dispersal, and reworking, it has been difficult to interpret the assemblages in terms of paleoenvironments and paleoclimate. Here, we report an in situ assemblage of Nothofagus leaves and pollen from the Friis Hills (77⁰ 45'S, 161⁰ 28'E). The leaves are preserved as carbonaceous impressions in brown, fissile shales that represent the deposits of a lake occupying a glacial valley. The leaves most probably accumulated from deciduous shrubs. Based on the stratigraphic relationship to a tephra with a 40 Ar/39 Ar age of c. 20 Ma, the leaf assemblage is of early Miocene age. Nothofagus pollen from the shale suggests that at least 3 species were represented. A total of 227 leaves were examined and lengths, widths, and areas recorded. The preservation is generally good but only a few of the specimens represent complete leaves; the spectrum is 30-100%. Plots of the measurements of the leaves provide a summary of size variation but were otherwise not useful for separating out different taxa . The most useful characters for establishing differences between the leaves were the leaf margins, of which three or four types were distinguished: 1. margins entire or finely serrate between ribs; 2. margins with one or two convex lobes between the ribs; 3. margins with convex lobes over the ribs. The leaf study indicates that three or possibly four species were co-inhabiting the valley in the early Miocene and were part of a dynamic vegetation that colonized the valley with each deglaciation. A possible analog today would be at low elevations in Tierra del Fuego where three species of Nothofagus coexist. The stem diameters of abundant wood preserved in adjacent facies indicates

  19. Cleaning of porous filters in fossilized bed reactors; Estudio de limpieza de filtros porosos en reactores de lecho fluidizado

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigo Otero, A.; Sancho Rod, J.

    1965-07-01

    In this report are established the optimum working conditions of a filter cleaning system by blow back. For this purpose it was determined in the first place the blow back air rate necessary to have a good cleaning. The reasons for which it was not possible until now to control the pressure in a fluidized bed calcination reactor are analyzed and a criteria is established to calculate the optimum floe necessary to clean efficiently a porous by this procedures. (Author)

  20. Sedimentary paleoenvironment and fossil plants of the El freno formation (early jurassic in Las leñas valley, Neuquén basin

    Directory of Open Access Journals (Sweden)

    Silvia Lanés

    2013-12-01

    Full Text Available Non-marine Early Jurassic successions in Las Leñas valley and their paleofloristic fossil content have been known since late nineteenth century, though they are scarce in the bibliography. It led us to study the sedimentology and paleobotanical content of El Freno Formation outcrops in the surroundings of the Portezuelo and Peuquenes creeks, report the first finding of fossil plants there and interpret their taphonomic features and enclosing sedimentary environment. The studied section is a lensoidal, fining- and thinning-upwards, conglomerate and sandy succession, with carbonaceous plant impressions and silicified trunks. It records the evolution of a gravel braided fluvial system (with longitudinal and transverse bars, abandoned channels and strong topographic irregularities into a sand braided fluvial system (with transverse bars, overbank deposits and no evidence of lateral migration. Both flowed mainly towards the NNW and show a continuously increasing accommodation probably driven by a relative base level rise and regional sag or erosional lowering of the topography. Collected fossil plants include Dictyophylum (Dictyophylum sp., Goeppertella sp. and undetermined Equisetopsida. Goeppertella sp. is recorded for the first time in this unit. Equisetopsida would have thrived in semi-permanent water bodies on abandoned channels and Dipteridaceae, in well-drained zones of the channel belt above the permanent channel level. Conversely, the trees would have lived in higher and well-drained areas with well-developed soils, probably outside the channel belt. Based largely on lithostratigraphical considerations, the age of the studied deposits was limited to the Hettangian?-Middle Sinemurian without identifying hiatus inside the fluvial succession or between it and the overlain marine beds.

  1. Scenes from the past: initial investigation of early jurassic vertebrate fossils with multidetector CT.

    Science.gov (United States)

    Bolliger, Stephan A; Ross, Steffen; Thali, Michael J; Hostettler, Bernhard; Menkveld-Gfeller, Ursula

    2012-01-01

    The study of fossils permits the reconstruction of past life on our planet and enhances our understanding of evolutionary processes. However, many fossils are difficult to recognize, being encased in a lithified matrix whose tedious removal is required before examination is possible. The authors describe the use of multidetector computed tomography (CT) in locating, identifying, and examining fossil remains of crocodilians (Mesosuchia) embedded in hard shale, all without removing the matrix. In addition, they describe how three-dimensional (3D) reformatted CT images provided details that were helpful for extraction and preparation. Multidetector CT can help experienced paleontologists localize and characterize fossils in the matrix of a promising rock specimen in a nondestructive manner. Moreover, with its capacity to generate highly accurate 3D images, multidetector CT can help determine whether the fossils warrant extraction and can assist in planning the extraction process. Thus, multidetector CT may well become an invaluable tool in the field of paleoradiology.

  2. Early Oligocene plant diversity along the Upper Rhine Graben: The fossil flora of Rauenberg, Germany

    Directory of Open Access Journals (Sweden)

    Kovar-Eder Johanna

    2016-12-01

    Full Text Available The macroflora of Rauenberg, Baden-Württemberg, Germany, is treated monographically. The plant-bearing sediments are marine, mainly well-bedded clay- to siltstones, the so-called Fischschiefer, which are part of the Bodenheim Formation. Based on nannoplankton they are dated to nannoplankton zone NP 23 (Rupelian, Lower Oligocene. The plant remains, mainly leaves and some fructifications, are preserved as compressions. The taxonomic assignment is based on gross morphology and cuticle characteristics. The flora yields marine algae and remains of the very diverse terrestrial flora. A total of 68 taxa, including three types of algae, one cycad, 12 conifers, and 49 dicots, among them 5 palms, are described. The following fossil species are described for the first time: Laurophyllum rauenbergense, Myrica obliquifolia, Distylium metzleri, ? Berchemia altorhenana, ? Ternstroemites maritiae, Trachelospermum kelleri, Oleinites altorhenana, O. rauenbergensis, Dicotylophyllum badense, D. oechsleri, D. vesiculaeferens, D. ziegleri, ? Viscophyllum hendriksiae, and Cladites vesiculaeferens. Dicotylophyllum vesiculaeferens and Cladites vesiculaeferens bear peculiar, complex cuticular structures presumably representing salt-secreting glands. Both taxa are interpreted to derive from one plant species of yet uncertain systematic affinity. The flora bears a high proportion of broad-leaved, presumably evergreen taxa, whereas the diversity of modern Arcto-Tertiary taxa (sensu Kvaček 1994 is rather low. Most abundant are Platanus neptuni, Daphnogene cinnamomifolia, and Tetraclinis salicornioides. On the family level, Lauraceae (10 species and Pinaceae (8 are most diverse, followed by Arecaceae (4-5, Cupressaceae, and Myricaceae (4 species each. Surprisingly, Fagaceae are documented solely by a single leaf of Eotrigonobalanus furcinervis f. haselbachensis, and the record of Pentaphyllaceae remains ambiguous (? Ternstroemites maritiae. Sloanea olmediaefolia is recorded

  3. On the horizon of Protopteryx and the early vertebrate fossil assemblages of the Jehol Biota

    Institute of Scientific and Technical Information of China (English)

    JIN Fan; ZHANG FuCheng; LI ZhiHeng; ZHANG JiangYong; LI Chun; ZHOU ZhongHe

    2008-01-01

    Protopteryx, a monotypic fossil bird discovered from the Sichakou basin in Fengning, Hebei, is the most primitive enantiornithine currently known. The bird-bearing strata do not contain the index fossils of the Yixian Formation in western Liaoning; the fish and bird fossils have more primitive features than the related forms found in the Yixian Formation, and the conchostracans are those usually distributed in the Dabeigou and Dadianzi formations in northern Hebei. Besides, the Protopteryx-bearing strata underlie the deposits bearing the index fossils of the Yixian Formation in the neighboring basin. Thus, it could be confirmed that the horizon of Protopteryx should be lower than the Yixian Formation, and is approximately equivalent to the Dadianzi Formation in northern Hebei. This is the lowest horizon of the known fossil birds in China and Mesozoic enantiornithine birds in the world. Accompanying Protop-teryx, there are other birds, acipenseriform fishes, salamanders, and mammals, which compose the Peipiaosteus fengningensis-Protopteryx fengningensis assemblage. This new assemblage traces the vertebrate evolution history of the Jehol Biota back to 130.7 Ma before. It is suggested that the de-marcation of the Jehol Biota should be based on the large-scale tectonic-sedimentary cycles, and Peipiaosteus, instead of Lycoptera, could be taken as the vertebrate representative of the Jehol Biota.

  4. Improved age control on early Homo fossils from the upper Burgi Member at Koobi Fora, Kenya

    DEFF Research Database (Denmark)

    Nielsen, Trine Kellberg

    2013-01-01

    To address questions regarding the evolutionary origin, radiation and dispersal of the genus Homo, it is crucial to be able to place the occurrence of hominin fossils in a high-resolution chronological framework. The period around 2 Ma (millions of years ago) in eastern Africa is of particular...... interest as it is at this time that a more substantial fossil record of the genus Homo is first found. Here we combine magnetostratigraphy and strontium (Sr) isotope stratigraphy to improve age control on hominin-bearing upper Burgi (UBU) deposits in Areas 105 and 131 on the Karari Ridge in the eastern......, the magnetostratigraphic data allow us to construct an age model for the UBU deposits. We provide detailed age constraints for 15 hominin fossils from Area 131, showing that key specimens such as cranium KNM-ER 1470, partial face KNM-ER 62000 and mandibles KNM-ER 1482, KNM-ER 1801, and KNM-ER 1802 can be constrained...

  5. Arthropod eyes: The early Cambrian fossil record and divergent evolution of visual systems.

    Science.gov (United States)

    Strausfeld, Nicholas J; Ma, Xiaoya; Edgecombe, Gregory D; Fortey, Richard A; Land, Michael F; Liu, Yu; Cong, Peiyun; Hou, Xianguang

    2016-03-01

    Four types of eyes serve the visual neuropils of extant arthropods: compound retinas composed of adjacent facets; a visual surface populated by spaced eyelets; a smooth transparent cuticle providing inwardly directed lens cylinders; and single-lens eyes. The first type is a characteristic of pancrustaceans, the eyes of which comprise lenses arranged as hexagonal or rectilinear arrays, each lens crowning 8-9 photoreceptor neurons. Except for Scutigeromorpha, the second type typifies Myriapoda whose relatively large eyelets surmount numerous photoreceptive rhabdoms stacked together as tiers. Scutigeromorph eyes are facetted, each lens crowning some dozen photoreceptor neurons of a modified apposition-type eye. Extant chelicerate eyes are single-lensed except in xiphosurans, whose lateral eyes comprise a cuticle with a smooth outer surface and an inner one providing regular arrays of lens cylinders. This account discusses whether these disparate eye types speak for or against divergence from one ancestral eye type. Previous considerations of eye evolution, focusing on the eyes of trilobites and on facet proliferation in xiphosurans and myriapods, have proposed that the mode of development of eyes in those taxa is distinct from that of pancrustaceans and is the plesiomorphic condition from which facetted eyes have evolved. But the recent discovery of enormous regularly facetted compound eyes belonging to early Cambrian radiodontans suggests that high-resolution facetted eyes with superior optics may be the ground pattern organization for arthropods, predating the evolution of arthrodization and jointed post-protocerebral appendages. Here we provide evidence that compound eye organization in stem-group euarthropods of the Cambrian can be understood in terms of eye morphologies diverging from this ancestral radiodontan-type ground pattern. We show that in certain Cambrian groups apposition eyes relate to fixed or mobile eyestalks, whereas other groups reveal concomitant

  6. Improved age control on early Homo fossils from the upper Burgi Member at Koobi Fora, Kenya

    NARCIS (Netherlands)

    Joordens, J.C.A.; Dupont-Nivet, G.; Feibel, C.S.; Spoor, F.; Sier, M.J.; Lubbe, J.H.J.L. van der; Kellberg Nielsen, T.; Knul, M.V.; Davies, G.R.; Vonhof, H.B.

    2013-01-01

    To address questions regarding the evolutionary origin, radiation and dispersal of the genus Homo, it is crucial to be able to place the occurrence of hominin fossils in a high-resolution chronological framework. The period around 2 Ma (millions of years ago) in eastern Africa is of particular inter

  7. Involvement of microbial mats in early fossilization by decay delay and formation of impressions and replicas of vertebrates and invertebrates

    Science.gov (United States)

    Iniesto, Miguel; Buscalioni, Ángela D.; Carmen Guerrero, M.; Benzerara, Karim; Moreira, David; López-Archilla, Ana I.

    2016-05-01

    Microbial mats have been hypothesized to improve the persistence and the preservation of organic remains during fossilization processes. We test this hypothesis with long-term experiments (up to 5.5 years) using invertebrate and vertebrate corpses. Once placed on mats, the microbial community coats the corpses and forms a three-dimensional sarcophagus composed of microbial cells and exopolymeric substances (EPS). This coverage provides a template for i) moulding superficial features, resulting in negative impressions, and ii) generating replicas. The impressions of fly setulae, fish scales and frog skin verrucae are shaped mainly by small cells in an EPS matrix. Microbes also replicate delicate structures such as the three successive layers that compose a fish eye. The sarcophagus protects the body integrity, allowing the persistence of inner organs such as the ovaries and digestive apparatus in flies, the swim bladder and muscles in fish, and the bone marrow in frog legs. This study brings strong experimental evidence to the idea that mats favour metazoan fossilization by moulding, replicating and delaying decay. Rapid burial has classically been invoked as a mechanism to explain exceptional preservation. However, mats may play a similar role during early fossilization as they can preserve complex features for a long time.

  8. Palaeoecology and depositional environments of the Tendaguru Beds (Late Jurassic to Early Cretaceous, Tanzania

    Directory of Open Access Journals (Sweden)

    M. Aberhan

    2002-01-01

    Full Text Available The Late Jurassic to Early Cretaceous Tendaguru Beds (Tanzania, East Africa have been well known for nearly a century for their diverse dinosaur assemblages. Here, we present sedimentological and palaeontological data collected by the German-Tanzanian Tendaguru Expedition 2000 in an attempt to reconstruct the palaeo-ecosystems of the Tendaguru Beds at their type locality. Our reconstructions are based on sedimentological data and on a palaeoecological analysis of macroinvertebrates, microvertebrates, plant fossils and microfossils (ostracods, foraminifera, charophytes, palynomorphs. In addition, we included data from previous expeditions, particularly those on the dinosaur assemblages. The environmental model of the Tendaguru Beds presented herein comprises three broad palaeoenvironmental units in a marginal marine setting: (1 Lagoon-like, shallow marine environments above fair weather wave base and with evidence of tides and storms. These formed behind barriers such as ooid bar and siliciclastic sand bar complexes and were generally subject to minor salinity fluctuations. (2 Extended tidal flats and low-relief coastal plains. These include low-energy, brackish coastal lakes and ponds as well as pools and small fluvial channels of coastal plains in which the large dinosaurs were buried. Since these environments apparently were, at best, poorly vegetated, the main feeding grounds of giant sauropods must have been elsewhere. Presumably, tidal flats and coastal plains were visited by dinosaurs primarily during periods of drought. (3 Vegetated hinterland. Vegetation of this environment can only be inferred indirectly from plant material transported into the other depositional environments. Vegetation was dominated by a diverse conifer flora, which apparently formed part of the food source of large herbivorous sauropods. Evidence from various sources suggests a subtropical to tropical palaeoclimate, characterised by seasonal rainfall alternating with

  9. A fossil biting midge (Diptera: Ceratopogonidae) from early Eocene Indian amber with a complex pheromone evaporator

    Science.gov (United States)

    Stebner, Frauke; Szadziewski, Ryszard; Rühr, Peter T.; Singh, Hukam; Hammel, Jörg U.; Kvifte, Gunnar Mikalsen; Rust, Jes

    2016-10-01

    The life-like fidelity of organisms captured in amber is unique among all kinds of fossilization and represents an invaluable source for different fields of palaeontological and biological research. One of the most challenging aspects in amber research is the study of traits related to behaviour. Here, indirect evidence for pheromone-mediated mating behaviour is recorded from a biting midge (Ceratopogonidae) in 54 million-year-old Indian amber. Camptopterohelea odora n. sp. exhibits a complex, pocket shaped structure on the wings, which resembles the wing folds of certain moth flies (Diptera: Psychodidae) and scent organs that are only known from butterflies and moths (Lepidoptera) so far. Our studies suggests that pheromone releasing structures on the wings have evolved independently in biting midges and might be much more widespread in fossil as well as modern insects than known so far.

  10. Into Tibet: An Early Pliocene Dispersal of Fossil Zokor (Rodentia: Spalacidae) from Mongolian Plateau to the Hinterland of Tibetan Plateau.

    Science.gov (United States)

    Li, Qiang; Wang, Xiaoming

    2015-01-01

    This paper reports the fossil zokors (Myospalacinae) collected from the lower Pliocene (~4.4 Ma) of Zanda Basin, southwestern Tibet, which is the first record in the hinterland of Tibetan Plateau within the Himalayan Range. Materials include 29 isolated molars belonging to Prosiphneus eriksoni (Schlosser, 1924) by having characters including large size, highly fused roots, upper molars of orthomegodont type, m1 anterior cap small and centrally located, and first pair of m1 reentrants on opposing sides, high crowns, and high value of dentine tract parameters. Based on the cladistics analysis, all seven species of Prosiphneus and P. eriksoni of Zanda form a monophyletic clade. P. eriksoni from Zanda, on the other hand, is nearly the terminal taxon of this clade. The appearance of P. eriksoni in Zanda represents a significant dispersal in the early Pliocene from its center of origin in north China and Mongolian Plateau, possibly via the Hol Xil-Qiangtang hinterland in northern Tibet. The fast evolving zokors are highly adapted to open terrains at a time when regional climates had become increasingly drier in the desert zones north of Tibetan Plateau during the late Miocene to Pliocene. The occurrence of this zokor in Tibet thus suggests a rather open steppe environment. Based on fossils of large mammals, we have formulated an "out of Tibet" hypothesis that suggests earlier and more primitive large mammals from the Pliocene of Tibet giving rise to the Ice Age megafauna. However, fossil records for large mammals are still too poor to evaluate whether they have evolved from lineages endemic to the Tibetan Plateau or were immigrants from outside. The superior record of small mammals is in a better position to address this question. With relatively dense age intervals and numerous localities in much of northern Asia, fossil zokors provide the first example of an "into Tibet" scenario--earlier and more primitive taxa originated from outside of the Tibetan Plateau and the

  11. The performance of field scientists undertaking observations of early life fossils while in simulated space suit

    Science.gov (United States)

    Willson, D.; Rask, J. C.; George, S. C.; de Leon, P.; Bonaccorsi, R.; Blank, J.; Slocombe, J.; Silburn, K.; Steele, H.; Gargarno, M.; McKay, C. P.

    2014-01-01

    We conducted simulated Apollo Extravehicular Activity's (EVA) at the 3.45 Ga Australian 'Pilbara Dawn of life' (Western Australia) trail with field and non-field scientists using the University of North Dakota's NDX-1 pressurizable space suit to overview the effectiveness of scientist astronauts employing their field observation skills while looking for stromatolite fossil evidence. Off-world scientist astronauts will be faced with space suit limitations in vision, human sense perception, mobility, dexterity, the space suit fit, time limitations, and the psychological fear of death from accidents, causing physical fatigue reducing field science performance. Finding evidence of visible biosignatures for past life such as stromatolite fossils, on Mars, is a very significant discovery. Our preliminary overview trials showed that when in simulated EVAs, 25% stromatolite fossil evidence is missed with more incorrect identifications compared to ground truth surveys but providing quality characterization descriptions becomes less affected by simulated EVA limitations as the science importance of the features increases. Field scientists focused more on capturing high value characterization detail from the rock features whereas non-field scientists focused more on finding many features. We identified technologies and training to improve off-world field science performance. The data collected is also useful for NASA's "EVA performance and crew health" research program requirements but further work will be required to confirm the conclusions.

  12. 云南罗平生物群产出层位沉积微相及其化石富集规律%Microfacies and enrichment pattern of fossils in the fossiliferous beds of Luoping Biota,Yunnan Province

    Institute of Scientific and Technical Information of China (English)

    白建科; 尹福光; 张启跃

    2011-01-01

    云南罗平上石坎剖面是产出罗平生物群的代表性剖面.参考Wilson的标准微相模式,从产化石层位识别出6种沉积微相:灰泥灰岩、生屑粒泥灰岩、粪球粒-生屑泥灰岩、纹层状泥晶灰岩、生屑泥粒灰岩和砾屑灰岩.通过在化石采掘现场对化石富集层位的统计,将产化石层位细分为生物群上层段UFH(Upper Fossil Horizon)和生物群下层段LFH(Lower Fossil Horizon),并进一步探讨了每个层段中沉积微相与化石富集规律的关系,发现化石富集程度高的层段主要发育灰泥灰岩、生屑粒泥灰岩、粪球粒-生屑泥灰岩、纹层状泥晶灰岩等4种沉积微相.这种沉积微相组合主要发育在深水、低能的台内盆地环境中,环境水体的滞留、缺氧给生物埋藏提供了良好的条件.%Shangshikan stratigraphic section in Luoping of Yunnan Province is a representative fossiliferous bed that produced Luoping Biota.According to the standard microfacies model put forward by Wilson (1975), the authors recognized six types of microfacies, i.e., marlite.bioclastic wackestone, pelleted -bioclastic marlite.laminated micrite, bioclastic packstone and calcirudite, in the fossiliferous bed of Shangshikan section.The fossiliferous bed can be subdivided into two horizons: the Upper Fossil Horizon (UFH) and the Lower Fossil Horizon (LFH).The relationship between microfacies and fossil enrichment in each fossiliferous horizon was further studied.The result reveals that four kinds of microfacies are mainly developed in the fossil-enriched horizons, comprising marlite.bioclastic wackestone, pelleted -bioclastic marlite and laminated micrite.whose assemblage always occurs in the deep, low-energy intra-platform basin.The water in this environment implies a high anoxic and retained condition, This study shows that this intra-platform basin is highly anoxic and retained.which is suitable for the preservation of fossils.

  13. Improved age control on early Homo fossils from the upper Burgi Member at Koobi Fora, Kenya

    DEFF Research Database (Denmark)

    Nielsen, Trine Kellberg

    2013-01-01

    Turkana Basin (Kenya). We identify the base of the Olduvai subchron (bC2n) plus a short isolated interval of consistently normal polarity that we interpret to be the Pre-Olduvai event. Combined with precession-forced (∼20 kyr [thousands of years]) wet–dry climate cycles resolved by Sr isotope ratios...... interest as it is at this time that a more substantial fossil record of the genus Homo is first found. Here we combine magnetostratigraphy and strontium (Sr) isotope stratigraphy to improve age control on hominin-bearing upper Burgi (UBU) deposits in Areas 105 and 131 on the Karari Ridge in the eastern...

  14. Virtual assessment of the endocranial morphology of the early modern European fossil calvaria from cioclovina, romania.

    Science.gov (United States)

    Kranioti, Elena F; Holloway, Ralph; Senck, Sascha; Ciprut, Tudor; Grigorescu, Dan; Harvati, Katerina

    2011-07-01

    Endocasts provide evidence on size and shape characteristics, blood supply trajectories, and neurological features of the brain, allowing comparative analyses of fossil hominins crucial to our understanding of human brain evolution. Here, we assess the morphological features of the virtual endocast of the Cioclovina Upper Paleolithic calvarium, one of the earliest reliably dated European modern human fossils. Our study was conducted on a computed tomography (CT) scan of the original specimen. The endocranial profile was approximated via a semiautomatic segmentation of the CT data. Virtual reconstructions of the endocast were used for assessing the morphological features of the endocranium and for the estimation of the endocranial volume. Cioclovina exhibits a clockwise torque with a small anterior extension of the left frontal lobe over the right one and a protrusion of the right occipital lobe over the left, most likely due to the superior sagittal sinus coursing over the occipital pole. There is an obvious right predominance of the posterior drainage system. Interestingly, the area of the frontal sinus is occupied by dense bony tissue with small air cells corresponding probably to a natural bony loss in the diploë and to vascular spaces. An estimated endocranial volume of 1498.53 cc was calculated. The convolutional details of the third inferior frontal gyrus (Broca's caps) are indistinguishable from those found in modern Homo sapiens, and the left occipital lobe appears wider than the right, a possible correlate of right-handedness. Our metric analysis of endocranial measurements also aligns Cioclovina with modern humans.

  15. Early members of 'living fossil' lineage imply later origin of modern ray-finned fishes.

    Science.gov (United States)

    Giles, Sam; Xu, Guang-Hui; Near, Thomas J; Friedman, Matt

    2017-08-30

    Modern ray-finned fishes (Actinopterygii) comprise half of extant vertebrate species and are widely thought to have originated before or near the end of the Middle Devonian epoch (around 385 million years ago). Polypterids (bichirs and ropefish) represent the earliest-diverging lineage of living actinopterygians, with almost all Palaeozoic taxa interpreted as more closely related to other extant actinopterygians than to polypterids. By contrast, the earliest material assigned to the polypterid lineage is mid-Cretaceous in age (around 100 million years old), implying a quarter-of-a-billion-year palaeontological gap. Here we show that scanilepiforms, a widely distributed radiation from the Triassic period (around 252-201 million years ago), are stem polypterids. Importantly, these fossils break the long polypterid branch and expose many supposedly primitive features of extant polypterids as reversals. This shifts numerous Palaeozoic ray-fins to the actinopterygian stem, reducing the minimum age for the crown lineage by roughly 45 million years. Recalibration of molecular clocks to exclude phylogenetically reassigned Palaeozoic taxa results in estimates that the actinopterygian crown lineage is about 20-40 million years younger than was indicated by previous molecular analyses. These new dates are broadly consistent with our revised palaeontological timescale and coincident with an interval of conspicuous morphological and taxonomic diversification among ray-fins centred on the Devonian-Carboniferous boundary. A shifting timescale, combined with ambiguity in the relationships of late Palaeozoic actinopterygians, highlights this part of the fossil record as a major frontier in understanding the evolutionary assembly of modern vertebrate diversity.

  16. Radiometric Dating of Ignimbrite from Inner Mongolia Provides no Indication of a Post-Middle Jurassic Age for the Daohugou Beds

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Lacustrine deposits exposed at Daohugou, Inner Mongolia, China, have yielded superbly preserved vertebrate fossils. The fossil beds were first misinterpreted as of Early Cretaceous age, based on alleged occurrences of key fossils of the Jehol Biota. Compelling evidence revealed by more rigorous research involving regional biostratigraphy, radiometric dating, and paleontology supports the Middle Jurassic age of the fossil beds. Despite the awesome evidence for the Middle Jurassic age of the Daohugou beds, the age dispute has been resurrected recently by invoking an overturned stratigraphic sequence. A careful review of the data, however, found no evidence that this sequence has been overturned. In addition, many of the assumptions, on which the conjecture of the fossil beds being postMiddle Jurassic is imprudently based, are self-contradictory or otherwise misleading. Thus, the postMiddle Jurassic age of the Daohugou beds as an unfounded conclusion can readily be dismissed.

  17. Extending the fossil record of Polytrichaceae: Early Cretaceous Meantoinea alophosioides gen. et sp. nov., permineralized gametophytes with gemma cups from Vancouver Island.

    Science.gov (United States)

    Bippus, Alexander C; Stockey, Ruth A; Rothwell, Gar W; Tomescu, Alexandru M F

    2017-04-01

    Diverse in modern ecosystems, mosses are dramatically underrepresented in the fossil record. Furthermore, most pre-Cenozoic mosses are known only from compression fossils, lacking detailed anatomical information. When preserved, anatomy vastly improves resolution in the systematic placement of fossils. Lower Cretaceous deposits at Apple Bay (Vancouver Island, British Columbia, Canada) contain a diverse anatomically preserved flora that includes numerous bryophytes, many of which have yet to be characterized. Among them is a polytrichaceous moss that is described here. Fossil moss gametophytes preserved in four carbonate concretions were studied in serial sections prepared using the cellulose acetate peel technique. We describe Meantoinea alophosioides gen. et sp. nov., a polytrichaceous moss with terminal gemma cups containing stalked, lenticular gemmae. Leaves with characteristic costal anatomy, differentiated into sheathing base and free lamina and bearing photosynthetic lamellae, along with a conducting strand in the stem, place Meantoinea in family Polytrichaceae. The bistratose leaf lamina with an adaxial layer of mamillose cells, short photosynthetic lamellae restricted to the costa, and presence of gemma cups indicate affinities with basal members of the Polytrichaceae, such as Lyellia, Bartramiopsis, and Alophosia. Meantoinea alophosioides enriches the documented moss diversity of an already-diverse Early Cretaceous plant fossil assemblage. This is the third moss described from the Apple Bay plant fossil assemblage and represents the first occurrence of gemma cups in a fossil moss. It is also the oldest unequivocal record of Polytrichaceae, providing a hard minimum age for the group of 136 million years. © 2017 Botanical Society of America.

  18. Atmospheric CO2 from the late Oligocene to early Miocene reconstructed from photosynthesis data and leaf characteristics of fossil plants

    Science.gov (United States)

    Grein, Michaela; Oehm, Christoph; Konrad, Wilfried; Utescher, Torsten; Kunzmann, Lutz; Roth-Nebelsick, Anita

    2013-04-01

    In the Cenozoic era, global climate changed from greenhouse to icehouse conditions. During the Oligocene, the comparatively cool phase in the earlier part of the late Oligocene is followed by the Late Oligocene Warming and a major glaciation event at the Oligocene-Miocene transition (Mi-1). Various studies indicate that these climate events were coupled to changes in atmospheric CO2 levels. In this study, atmospheric CO2 from the late Oligocene to the early Miocene was reconstructed by using photosynthesis data and fossil leaf characteristics. We used plant material from various sites located in Germany and Austria comprising fossil leaves of four angiosperm plant species: Platanus neptuni (Platanaceae), Quercus rhenana, Q. praerhenana and Eotrigonobalanus furcinervis (all Fagaceae). A mechanistic-theoretical approach based on stomatal parameters, photosynthesis data and gas exchange parameters was applied to model palaeoatmospheric CO2 levels. Detailed climate data of the considered sites were reconstructed as well since the mechanistic-theoretical approach requires climate data as input parameters for calculating both assimilation rate and transpiration rate. Our results indicate a steady CO2 level of about 400 ppm for all sites and therefore suggest a decoupling of CO2 and cooling/warming events for the considered time slices.

  19. New Fossil Evidence on the Sister-Group of Mammals and Early Mesozoic Faunal Distributions

    Science.gov (United States)

    Shubin, Neil H.; Crompton, A. W.; Sues, Hans-Dieter; Olsen, Paul E.

    1991-03-01

    Newly discovered remains of highly advanced mammal-like reptiles (Cynodontia: Tritheledontidae) from the Early Jurassic of Nova Scotia, Canada, have revealed that aspects of the characteristic mammalian occlusal pattern are primitive. Mammals and tritheledontids share an homologous pattern of occlusion that is not seen in other cynodonts. The new tritheledontids represent the first definite record of this family from North America. The extreme similarity of North American and African tritheledontids supports the hypothesis that the global distribution of terrestrial tetrapods was homogeneous in the Early Jurassic. This Early Jurassic cosmopolitanism represents the continuation of a trend toward increased global homogeneity among terrestrial tetrapod communities that began in the late Paleozoic.

  20. Hettangian (early jurassic) plant fossils from Puale Bay (peninsular terrane, Alaska)

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Middle Hettangian (Early Jurassic) plant macrofossils from the Kamishak Formation at Puale Bay,Alaska occur mainly as leaves and leafy shoots found together with...

  1. Growth ring analysis of fossil coniferous woods from early cretaceous of Araripe Basin.

    Science.gov (United States)

    Pires, Etiene F; Guerra-Sommer, Margot

    2011-06-01

    Growth ring analysis on silicified coniferous woods from the Missão Velha Formation (Araripe Basin - Brazil) has yielded important information about periodicity of wood production during the Early Cretaceous in the equatorial belt. Despite warm temperatures, dendrological data indicate that the climate was characterized by cyclical alternation of dry and rainy periods influenced by cyclical precipitations, typical of tropical wet and dry or savanna climate. The abundance of false growth rings can be attributed to both occasional droughts and arthropod damage. The present climate data agree with palaeoclimatic models that inferred summer-wet biomes for the Late Jurassic/Early Cretaceous boundary in the southern equatorial belt.

  2. Individual to community-level faunal responses to environmental change from a marine fossil record of Early Miocene global warming.

    Science.gov (United States)

    Belanger, Christina L

    2012-01-01

    Modern climate change has a strong potential to shift earth systems and biological communities into novel states that have no present-day analog, leaving ecologists with no observational basis to predict the likely biotic effects. Fossil records contain long time-series of past environmental changes outside the range of modern observation, which are vital for predicting future ecological responses, and are capable of (a) providing detailed information on rates of ecological change, (b) illuminating the environmental drivers of those changes, and (c) recording the effects of environmental change on individual physiological rates. Outcrops of Early Miocene Newport Member of the Astoria Formation (Oregon) provide one such time series. This record of benthic foraminiferal and molluscan community change from continental shelf depths spans a past interval environmental change (≈ 20.3-16.7 mya) during which the region warmed 2.1-4.5°C, surface productivity and benthic organic carbon flux increased, and benthic oxygenation decreased, perhaps driven by intensified upwelling as on the modern Oregon coast. The Newport Member record shows that (a) ecological responses to natural environmental change can be abrupt, (b) productivity can be the primary driver of faunal change during global warming, (c) molluscs had a threshold response to productivity change while foraminifera changed gradually, and (d) changes in bivalve body size and growth rates parallel changes in taxonomic composition at the community level, indicating that, either directly or indirectly through some other biological parameter, the physiological tolerances of species do influence community change. Ecological studies in modern and fossil records that consider multiple ecological levels, environmental parameters, and taxonomic groups can provide critical information for predicting future ecological change and evaluating species vulnerability.

  3. Individual to community-level faunal responses to environmental change from a marine fossil record of Early Miocene global warming.

    Directory of Open Access Journals (Sweden)

    Christina L Belanger

    Full Text Available Modern climate change has a strong potential to shift earth systems and biological communities into novel states that have no present-day analog, leaving ecologists with no observational basis to predict the likely biotic effects. Fossil records contain long time-series of past environmental changes outside the range of modern observation, which are vital for predicting future ecological responses, and are capable of (a providing detailed information on rates of ecological change, (b illuminating the environmental drivers of those changes, and (c recording the effects of environmental change on individual physiological rates. Outcrops of Early Miocene Newport Member of the Astoria Formation (Oregon provide one such time series. This record of benthic foraminiferal and molluscan community change from continental shelf depths spans a past interval environmental change (≈ 20.3-16.7 mya during which the region warmed 2.1-4.5°C, surface productivity and benthic organic carbon flux increased, and benthic oxygenation decreased, perhaps driven by intensified upwelling as on the modern Oregon coast. The Newport Member record shows that (a ecological responses to natural environmental change can be abrupt, (b productivity can be the primary driver of faunal change during global warming, (c molluscs had a threshold response to productivity change while foraminifera changed gradually, and (d changes in bivalve body size and growth rates parallel changes in taxonomic composition at the community level, indicating that, either directly or indirectly through some other biological parameter, the physiological tolerances of species do influence community change. Ecological studies in modern and fossil records that consider multiple ecological levels, environmental parameters, and taxonomic groups can provide critical information for predicting future ecological change and evaluating species vulnerability.

  4. A newly recognized fossil coelacanth highlights the early morphological diversification of the clade.

    Science.gov (United States)

    Friedman, Matt; Coates, Michael I

    2006-01-22

    Previously considered an actinopterygian or an osteichthyan incertae sedis, the Devonian (Givetian-Frasnian) Holopterygius nudus is reinterpreted as a coelacanth. This genus is among the oldest coelacanths known from articulated remains, but its eel-like morphology marks a considerable departure from the conventional coelacanth body plan. A cladistic analysis places Holopterygius as the sister taxon of the Carboniferous (Serpukhovian) genus Allenypterus. Despite the specialized morphology of these genera, they occupy a surprisingly basal position in coelacanth phylogeny; only Diplocercides and Miguashaia are further removed from the crown. A morphometric analysis reveals that coelacanths were anatomically disparate early in their history. Conflicts between this result and those of previous studies challenge the adequacy of systematic character sets for describing historical patterns of morphological variety. Coelacanths have long had an iconic place in the study of vertebrate evolution for their apparent anatomical conservatism over geological time, but Holopterygius provides clear evidence for rapid morphological evolution early in the history of this clade.

  5. Early Tertiary marine fossils from northern Alaska: implications for Arctic Ocean paleogeography and faunal evolution.

    Science.gov (United States)

    Marincovich, L.; Brouwers, E.M.; Carter, L.D.

    1985-01-01

    Marine mollusks and ostracodes indicate a post-Danian Paleocene to early Eocene (Thanetian to Ypresian) age for a fauna from the Prince Creek Formation at Ocean Point, northern Alaska, that also contains genera characteristic of the Cretaceous and Neogene-Quaternary. The life-assocation of heterochronous taxa at Ocean Point resulted from an unusual paleogeographic setting, the nearly complete isolation of the Arctic Ocean from about the end of the Cretaceous until sometime in the Eocene, in which relict Cretaceous taxa survived into Tertiary time while endemic taxa evolved in situ; these later migrated to the northern mid- latitudes. Paleobiogeographic affinities of the Ocean Point assocation with mild temperate faunas of the London Basin (England), Denmark, and northern Germany indicate that a shallow, intermittent Paleocene seaway extended through the Norwegian-Greenland Sea to the North Sea Basin. Early Tertiary Arctic Ocean paleogeography deduced from faunal evidence agrees with that inferred from plate-tectonic reconstructions.-Authors

  6. Early modern humans and morphological variation in Southeast Asia: fossil evidence from Tam Pa Ling, Laos.

    Directory of Open Access Journals (Sweden)

    Fabrice Demeter

    Full Text Available Little is known about the timing of modern human emergence and occupation in Eastern Eurasia. However a rapid migration out of Africa into Southeast Asia by at least 60 ka is supported by archaeological, paleogenetic and paleoanthropological data. Recent discoveries in Laos, a modern human cranium (TPL1 from Tam Pa Ling's cave, provided the first evidence for the presence of early modern humans in mainland Southeast Asia by 63-46 ka. In the current study, a complete human mandible representing a second individual, TPL 2, is described using discrete traits and geometric morphometrics with an emphasis on determining its population affinity. The TPL2 mandible has a chin and other discrete traits consistent with early modern humans, but it retains a robust lateral corpus and internal corporal morphology typical of archaic humans across the Old World. The mosaic morphology of TPL2 and the fully modern human morphology of TPL1 suggest that a large range of morphological variation was present in early modern human populations residing in the eastern Eurasia by MIS 3.

  7. Fossil Explorers

    Science.gov (United States)

    Moran, Sean; McLaughlin, Cheryl; MacFadden, Bruce; Jacobbe, Elizabeth; Poole, Michael

    2015-01-01

    Many young learners are fascinated with fossils, particularly charismatic forms such as dinosaurs and giant sharks. Fossils provide tangible, objective evidence of life that lived millions of years ago. They also provide a timescale of evolution not typically appreciated by young learners. Fossils and the science of paleontology can, therefore,…

  8. Marquee Fossils

    Science.gov (United States)

    Clary, Renee; Wandersee, James

    2008-01-01

    Professors of an online graduate-level paleontology class developed the concept of marquee fossils--fossils that have one or more unique characteristics that capture the attention and direct observation of students. In the classroom, Marquee fossils integrate the geology, biology, and environmental science involved in the study of fossilized…

  9. Fossil Explorers

    Science.gov (United States)

    Moran, Sean; McLaughlin, Cheryl; MacFadden, Bruce; Jacobbe, Elizabeth; Poole, Michael

    2015-01-01

    Many young learners are fascinated with fossils, particularly charismatic forms such as dinosaurs and giant sharks. Fossils provide tangible, objective evidence of life that lived millions of years ago. They also provide a timescale of evolution not typically appreciated by young learners. Fossils and the science of paleontology can, therefore,…

  10. Reconstructing early sponge relationships by using the Burgess Shale fossil Eiffelia globosa, Walcott.

    Science.gov (United States)

    Botting, Joseph P; Butterfield, Nicholas J

    2005-02-01

    The relationships of the sponge classes are controversial, particularly between the calcareous and siliceous sponges. Specimens of the putative calcarean Eiffelia globosa Walcott from the Burgess Shale show the presence of diagnostic hexactinellid spicules integrated into the skeletal mesh. The arrangement of these spicules in Eiffelia is shown to be precisely equivalent to that of early protospongioid hexactinellids, and sponge growth occurred through an identical pattern to produce identical skeletal body morphology. The difference in spicule composition of the classes is interpreted through the observation of taphonomic features of Eiffelia that suggest the presence of at least two mineralogically distinct layers within the spicules. These results support molecular analyses that identify the calcarean-silicisponge transition as the earliest major sponge branch and suggest that the heteractinids were paraphyletic with respect to the Hexactinellida.

  11. Growth ring analysis of fossil coniferous woods from early cretaceous of Araripe Basin (Brazil

    Directory of Open Access Journals (Sweden)

    Etiene F. Pires

    2011-06-01

    Full Text Available Growth ring analysis on silicified coniferous woods from the Missão Velha Formation (Araripe Basin - Brazil has yielded important information about periodicity of wood production during the Early Cretaceous in the equatorial belt. Despite warm temperatures, dendrological data indicate that the climate was characterized by cyclical alternation of dry and rainy periods influenced by cyclical precipitations, typical of tropical wet and dry or savanna climate. The abundance of false growth rings can be attributed to both occasional droughts and arthropod damage. The present climate data agree with palaeoclimatic models that inferred summer-wet biomes for the Late Jurassic/Early Cretaceous boundary in the southern equatorial belt.A partir de análise de anéis de crescimento em lenhos de coníferas silicificadas provenientes da Formação Missão Velha(Bacia do Araripe - Brasil, obteve-se importantes informações a respeito da periodicidade de produção lenhosa duranteo início do Cretáceo, na região do equador. Apesar das estimativas de temperatura apresentarem-se elevadas, os dados dendrológicos indicam que o clima foi caracterizado pela alternância cíclica de períodos secos e chuvosos, influenciado por precipitações periódicas, típico das condições atuais de climatropical úmido e seco ou savana. A abundância de falsosanéis de crescimento pode ser atribuída tanto a secas ocasionais quanto a danos causados por artrópodes. Os dados paleoclimáticos aqui obtidos corroboram com modelos paleoclimáticos que inferem a ocorrência de um bioma de verões úmidos para o limite Neojurássico/Eocretáceo ao sul do equador.

  12. The internal structure of Early Cambrian fossil embryo Olivooides revealed in the light of Synchrotron X-ray Tomographic Microscopy

    Institute of Scientific and Technical Information of China (English)

    CHEN Fang; DONG XiPing

    2008-01-01

    Countless fossil embryo Olivooides and the hatched larvae, juveniles and adults (the latter two kinds are Punctatus) are recovered by means of acid maceration from the fine-crystalline to medium-crystalline phosphatic limestone and phosphatic micrite of Early Cambrian Kuanchuanpu Formation at the Shizhonggou section, near Kuanchuanpu Village, Ningqiang County, Shaanxi Province, China. Using the technique of Synchrotron X-ray Tomographic Microscopy, the 3D internal structure of Olivooides and Punctatus is reconstructed. The morphological and statistic analyses are also given to the stellae structure of Olivooides and Punctatus, which indicates that this structure is a result of adaptive evolution to a lifestyle of fast-attaching after hatching, probably with the function of mucilage secretion. The internal structure of Punctatus is described and discussed. The ovum-like structure, a common internal feature of Punctatus, is considered as the taphonomic structure, rather than eggs or other biological structure. This structure is thought to be formed after the burial of the animal and before or during the mineralization. The original internal structure of Punctatus is assumed to be tabulae-filled, with soft body grown on them.

  13. Under-flap stromal bed CXL for early post-LASIK ectasia: a novel treatment technique.

    Science.gov (United States)

    Wallerstein, Avi; Adiguzel, Eser; Gauvin, Mathieu; Mohammad-Shahi, Nima; Cohen, Mark

    2017-01-01

    Collagen cross-linking (CXL) for post-laser-assisted in situ keratomileusis (LASIK) ectasia (PLE) is traditionally performed either epi-on or epi-off on the corneal surface. This study describes a novel technique in treating early PLE with under-flap CXL (ufCXL) to the stromal bed and reports on 6-month outcomes. Case series of seven patients (eight eyes) with topography-diagnosed early PLE treated with ufCXL. Inclusion criteria were early, mild PLE defined as new-onset postoperative manifest refraction cylinder ≤1.50 D, with new topographic inferior steepening consistent with ectasia, uncorrected distance visual acuity (UDVA) of 20/40 or better, and corrected distance visual acuity (CDVA) of 20/25 or better. Existing LASIK flap was lifted, riboflavin was applied directly to the stromal bed, flap was repositioned, and 18 mW/cm(2) ultraviolet light was applied for 3 minutes to the corneal surface. Post-ufCXL manifest refraction, UDVA and CDVA, corneal cylinder, Kmax, and corneal irregularity index were compared with pre-ufCXL measurements. Patients had a pre-ufCXL sphere of 0.09±0.48 D and cylinder of -0.78±0.49 D. At 6 months, post-ufCXL sphere (0.06±0.8 D; P=0.89) and cylinder (-1.09±0.76 D, P=0.26) were unchanged. Cumulative post-ufCXL UDVA was unchanged, achieving 20/20, 20/30, and 20/40 in 25%, 88%, and 88%, respectively, compared with 13%, 63%, and 88% pre-ufCXL (P=0.68). Post-ufCXL CDVA was unchanged (P=0.93) with a gain of one line in two eyes, a loss of one line in one eye, and five eyes unchanged. The efficacy index (P=0.76), safety index (P=0.89), Kmax (P=0.94), and corneal irregularity index (P=0.73) were also unchanged. Preliminary results with ufCXL for early PLE are promising, demonstrating maintenance of visual accuracy, efficacy, safety, Kmax, and cylinder, with much quicker recovery times than surface CXL.

  14. Bed rest versus early ambulation with standard anticoagulation in the management of deep vein thrombosis: a meta-analysis.

    Directory of Open Access Journals (Sweden)

    Zhenlei Liu

    Full Text Available Bed rest has been considered as the cornerstone of management of deep vein thrombosis (DVT for a long time, though it is not evidence-base, and there is growing evidence favoring early ambulation.Electronic databases including Medline, PubMed, Cochrane Library and three Chinese databases were searched with key words of "deep vein thrombosis", "pulmonary embolism", "venous thrombosis", "bed rest", "immobilization", "mobilization" and "ambulation". We considered randomized controlled trials, prospective or retrospective cohort studies that compared the outcomes of acute DVT patients managed with early ambulation versus bed rest, in addition to standard anticoagulation. Meta-analysis pertaining to the incidence of new pulmonary embolism (PE, progression of DVT, and DVT related deaths were conducted, as well as the extent of remission of pain and edema.13 studies were included with a total of 3269 patients. Compared to bed rest, early ambulation was not associated with a higher incidence of new PE, progression of DVT, or DVT related deaths (RD -0.03, 95% CI -0.05∼ -0.02; Z = 1.24, p = 0.22; random effect model, Tau2 = 0.01. Moreover, if the patients suffered moderate or severe pain initially, early ambulation was related to a better outcome, with respect to remission of acute pain in the affected limb (SMD 0.42, 95%CI 0.09∼0.74; Z = 2.52, p = 0.01; random effect model, Tau2 = 0.04. Meta-analysis of alleviation of edema cannot elicit a solid conclusion because of significant heterogeneity among the few studies.Compared to bed rest, early ambulation of acute DVT patients with anticoagulation was not associated with a higher incidence of new PE, progression of DVT, and DVT related deaths. Furthermore, for the patients suffered moderate or severe pain initially, a better outcome can be seen in early ambulation group, regarding to the remission of acute pain in the affected limb.

  15. Early evolution and historical biogeography of fishflies (Megaloptera: Chauliodinae: implications from a phylogeny combining fossil and extant taxa.

    Directory of Open Access Journals (Sweden)

    Xingyue Liu

    Full Text Available Fishflies (Corydalidae: Chauliodinae are one of the main groups of the basal holometabolous insect order Megaloptera, with ca. 130 species distributed worldwide. A number of genera from the Southern Hemisphere show remarkably disjunctive distributions and are considered to be the austral remnants or "living fossils" of Gondwana. Hitherto, the evolutionary history of fishflies remains largely unexplored due to limited fossil record and incomplete knowledge of phylogenetic relationships. Here we describe two significant fossil species of fishflies, namely Eochauliodes striolatus gen. et sp. nov. and Jurochauliodes ponomarenkoi Wang & Zhang, 2010 (original designation for fossil larvae only, from the Middle Jurassic of Inner Mongolia, China. These fossils represent the earliest fishfly adults. Furthermore, we reconstruct the first phylogenetic hypothesis including all fossil and extant genera worldwide. Three main clades within Chauliodinae are recognized, i.e. the Dysmicohermes clade, the Protochauliodes clade, and the Archichauliodes clade. The phylogenetic and dispersal-vicariance (DIVA analyses suggest Pangaean origin and global distribution of fishflies before the Middle Jurassic. The generic diversification of fishflies might have happened before the initial split of Pangaea, while some Gondwanan-originated clades were likely to be affected by the sequential breakup of Pangaea. The modern fauna of Asian fishflies were probably derived from their Gondwanan ancestor but not the direct descendents of the Mesozoic genera in Asia.

  16. Ediacara Fossils

    Science.gov (United States)

    Science Teacher, 2005

    2005-01-01

    Now, a research team from Virginia Tech and Nanjing Institute of Geology and Paleontology has discovered uniquely well-preserved fossil forms from 550-million-year-old rocks of the Ediacaran Period. The research appears in the Proceedings of the National Academy of Sciences. The discovery of these unusually preserved fossils reveals unprecedented…

  17. Fossil Fuels.

    Science.gov (United States)

    Crank, Ron

    This instructional unit is one of 10 developed by students on various energy-related areas that deals specifically with fossil fuels. Some topics covered are historic facts, development of fuels, history of oil production, current and future trends of the oil industry, refining fossil fuels, and environmental problems. Material in each unit may…

  18. Fossil Fuels.

    Science.gov (United States)

    Crank, Ron

    This instructional unit is one of 10 developed by students on various energy-related areas that deals specifically with fossil fuels. Some topics covered are historic facts, development of fuels, history of oil production, current and future trends of the oil industry, refining fossil fuels, and environmental problems. Material in each unit may…

  19. First known fossil bird tracks on San Salvador island, Bahamas

    National Research Council Canada - National Science Library

    Martin, A.J; Whitten, M.J

    2015-01-01

    ...) are the first known vertebrate trace fossils on this well-studied island. The trace fossils, preserved as bedding-plane impressions in an oolitic-bioclastic grainstone, match the size and form of tracks made by modern gulls...

  20. The early Eocene birds of the Messel fossil site: a 48 million-year-old bird community adds a temporal perspective to the evolution of tropical avifaunas.

    Science.gov (United States)

    Mayr, Gerald

    2016-04-08

    Birds play an important role in studies addressing the diversity and species richness of tropical ecosystems, but because of the poor avian fossil record in all extant tropical regions, a temporal perspective is mainly provided by divergence dates derived from calibrated molecular analyses. Tropical ecosystems were, however, widespread in the Northern Hemisphere during the early Cenozoic, and the early Eocene German fossil site Messel in particular has yielded a rich avian fossil record. The Messel avifauna is characterized by a considerable number of flightless birds, as well as a high diversity of aerial insectivores and the absence of large arboreal birds. With about 70 currently known species in 42 named genus-level and at least 39 family-level taxa, it approaches extant tropical biotas in terms of species richness and taxonomic diversity. With regard to its taxonomic composition and presumed ecological characteristics, the Messel avifauna is more similar to the Neotropics, Madagascar, and New Guinea than to tropical forests in continental Africa and Asia. Because the former regions were geographically isolated during most of the Cenozoic, their characteristics may be due to the absence of biotic factors, especially those related to the diversification of placental mammals, which impacted tropical avifaunas in Africa and Asia. The crown groups of most avian taxa that already existed in early Eocene forests are species-poor. This does not support the hypothesis that the antiquity of tropical ecosystems is key to the diversity of tropical avifaunas, and suggests that high diversification rates may be of greater significance.

  1. Selective Preservation of Fossil Ghost Fish

    Science.gov (United States)

    Meacham, Amanda

    2016-04-01

    A unique type of fossil fish preservation has been discovered in the Angelo Member (Fossil Lake) of the Green River Formation. The Angelo Member is a predominately evaporative deposit dominated by dolomite, but contains facies of fossiliferous laminated calcimicrite. Fossil fish occurring in two beds conspicuously lack bones. Fish in the lower bed are only preserved as organic material, including skin, pigments, and eyes. Fish in the upper bed have three-dimensional etching where bones once existed but also contain skin, pigments, and eyes. The top third of the upper bed often contains calcite crystals that are pseudomorphs after trona and possibly halite. Preliminary mineralogical analysis and mapping of evaporate facies suggests that this unique preservation may be related to lake geochemical conditions, such as high pH and alkalinity. To our knowledge, this is the first time this type of preservation has been observed and studied. Fossils and sediments within these beds are being studied both vertically and laterally through the one-meter thick sequence containing the fossil fish using XRD, isotopic, SEM, thin section, and total organic carbon analysis. Nine quarries, 0.5-1 meter square, were excavated for both fossils and rock samples along with 17 additional rock sample locations across an approximately 25-kilometer square region. This investigation has the capability of reconstructing the paleoenvironment and lake chemistry of Fossil Lake during the deposition of the "ghost-fish" beds and solving the mystery of the "missing bones" and the unusual process of preservation.

  2. New fossil evidence of the early diversification of scarabs:Alloioscarabaeus cheni (Coleoptera: Scarabaeoidea) from the Middle Jurassic of Inner Mongolia, China

    Institute of Scientific and Technical Information of China (English)

    Ming Bai; Dirk Ahrens; Xing-Ke Yang; Dong Ren

    2012-01-01

    Scarabaeoidea are known from the Lower Jurassic and may have originated in the Triassic based on fossil evidence and phylogenetic research.However,the early diversification of Scarabaeoidea remains unclear due to the lack of high-quality fossil evidence.Here we describe an exceptionally well-preserved new fossil of Scarabaeoidea,Alloioscarabaeus cheni gen.et sp.nov from the Middle Jurassic Jiulongshan Formation of Inner Mongolia,China.Based on a morphometric analysis using 17 landmarks of the hind wing of Alloioscarabaeus and 10 scarabaeoid families,we found that Alloioscarabaeus cheni gen.et sp.nov clearly does not belong to any of the known scarabaeoid families and,consequently,is a new family,Alloioscarabaeidae fam.nov.,was erected.The discovery of Alloioscarabaeus brought further evidence for the early diversification of major scarab lineages which could allow more detail in the palaeobiogeography of the Scarabaeoidea and Northeast of China which might be one of the originating places or an important radiation place during the evolution of Scarabaeoidea.Alloioscarabaeidae were very likely not good diggers and might have fed on decaying organic materials.Based on the evidence we have now,we tend to believe that most families and some subfamilies of Scarabaeoidea were present in the Jurassic period.

  3. Taphonomy of Early Triassic fish fossils of the Vega-Phroso Siltstone Member of the Sulphur Mountain Formation near Wapiti Lake, British Columbia, Canada

    Directory of Open Access Journals (Sweden)

    Karen Anderson

    2013-10-01

    Full Text Available The taphonomy of fishes living in lacustrine environments has been extensively studied in both the laboratory and the fossil record; the taphonomy of marine fishes, however, is poorly known. Triassic marine fishes with heavy ganoid and cosmoid scales, which provided protection from rapid taphonomic loss, offer a means to examine marine fish taphonomy in the fossil record. Four genera of Early Triassic fishes (the ray-finned actinopterygians Albertonia, Bobasatrania, Boreosomus, and the lobe-finned coelacanth (sarcopterygian, Whiteia from the Wapiti Lake, British Columbia locality of the Lower Triassic Sulphur Mountain Formation were examined in order to gain a better understanding of the taphonomy of fish in marine environments, determine ambient environmental conditions in the region during the Early Triassic, and ascertain the habitat and mode of life of the fish. Results indicate that environmental conditions that contributed to the preservation of the fossil fishes of the current study included deposition in deep, quiet waters, which reduced the odds of disarticulation, colder waters under higher pressure, which slowed decay and limited postmortem floatation, and waters that were anoxic, which discouraged predators and scavengers. In addition, the thickness of the primitive ganoid and cosmoid scales of the fossil fishes also increased their preservation potential. Taphonomic, physiological and environmental indicators suggest that Whiteia, Albertonia, and possibly Bobasatrania lived in deep, cold waters near the oxygen minimum zone, while Boreosomus lived higher in the water column. While the anatomical and physiological characteristics of modern fishes will likely continue to inhibit marine taphonomy studies, examination of ancient fish, particularly those with ganoid or cosmoid scales, may provide future avenues of research to gain a better understanding of marine fish taphonomy and provide a powerful tool to examine ancient fish behavior

  4. Valdivian ecosystems in the late Cretaceous and early Tertiary of Antarctica: further evidence from myrtaceous and eucryphiaceous fossil wood

    NARCIS (Netherlands)

    Poole, I.J.; Mennega, A.M.W.; Cantrill, David J.

    2003-01-01

    Cool temperate rainforests growing on the flanks of the Andes and along the Coastal Range in Valdivia (Chile) today provide the closest analogue for the fossil floras of Antarctica during the Eocene. This paper records key Valdivian elements in a Maastrichtian to Eocene wood flora that extends the

  5. An Early Cretaceous Ginkgo ovule-bearing organ fossil from Liaoning, Northeast China and its evolutionary implications

    Institute of Scientific and Technical Information of China (English)

    DENG Shenghui; YANG Xiaoju; ZHOU Zhiyan

    2004-01-01

    @@ Ginkgo is a very important gymnospermous genus that has only one surviving species, Ginkgo biloba L. As a so-called "living fossil", wild Ginkgo was found only in China, but it once flourished well and had a world-wide distribution in the Mesozoic. The earliest Ginkgo has been known from the Middle Jurassic, based on ovule-bearing organs[

  6. Taphonomy of the vertebrate bone beds from the Klūnas fossil site, Upper Devonian Tērvete Formation of Latvia

    Directory of Open Access Journals (Sweden)

    Jeļena Vasiļkova

    2012-05-01

    Full Text Available Combined sedimentological and taphonomical study of the siliciclastic sequence of the Tērvete Formation in the stratotypical area was aimed at revealing the formation of the three oryctocoenoses discovered and related structural and textural features of the deposits, as well as at detailed observation of the taphonomical peculiarities of the obtained palaeontological material. The fossil vertebrate assemblage is represented by 14 taxa comprising placoderms, acanthodians, sarcopterygians and actinopterygians. The three oryctocoenoses, first recognized in 2010, differ in the proportions of repeatedly buried material, in the number and degree of preservation of small and fragile skeletal elements, as well as in the evaluated current velocity and the transportation distance. Sedimentary concentrations of marine vertebrate remains, dominated by the antiarchs Bothriolepis ornata and B. jani, have been formed under the influence of fluvial and tidal processes in the shallow-water environment, deltaic or estuarine settings. Elongated placoderm and sarcopterygian bones are probably better indicators of the palaeoflow direction than acanthodian spines or sarcopterygian teeth.

  7. A new hynobiid-like salamander (Amphibia, Urodela from Inner Mongolia, China, provides a rare case study of developmental features in an Early Cretaceous fossil urodele

    Directory of Open Access Journals (Sweden)

    Jia Jia

    2016-10-01

    Full Text Available A new fossil salamander, Nuominerpeton aquilonaris (gen. et sp. nov., is named and described based on specimens from the Lower Cretaceous Guanghua Formation of Inner Mongolia, China. The new discovery documents a far northern occurrence of Early Cretaceous salamanders in China, extending the geographic distribution for the Mesozoic fossil record of the group from the Jehol area (40th–45th parallel north to near the 49th parallel north. The new salamander is characterized by having the orbitosphenoid semicircular in shape; coracoid plate of the scapulocoracoid greatly expanded with a convex ventral and posterior border; ossification of two centralia in carpus and tarsus; and first digit being about half the length of the second digit in both manus and pes. The new salamander appears to be closely related to hynobiids, although this inferred relationship awaits confirmation by research in progress by us on a morphological and molecular combined analysis of cryptobranchoid relationships. Comparison of adult with larval and postmetamorphic juvenile specimens provides insights into developmental patterns of cranial and postcranial skeletons in this fossil species, especially resorption of the palatine and anterior portions of the palatopterygoid in the palate and the coronoid in the mandible during metamorphosis, and postmetamorphic ossification of the mesopodium in both manus and pes. Thus, this study provides a rare case study of developmental features in a Mesozoic salamander.

  8. The early evolution of land plants, from fossils to genomics: a commentary on Lang (1937) 'On the plant-remains from the Downtonian of England and Wales'.

    Science.gov (United States)

    Edwards, Dianne; Kenrick, Paul

    2015-04-19

    During the 1920s, the botanist W. H. Lang set out to collect and investigate some very unpromising fossils of uncertain affinity, which predated the known geological record of life on land. His discoveries led to a landmark publication in 1937, 'On the plant-remains from the Downtonian of England and Wales', in which he revealed a diversity of small fossil organisms of great simplicity that shed light on the nature of the earliest known land plants. These and subsequent discoveries have taken on new relevance as botanists seek to understand the plant genome and the early evolution of fundamental organ systems. Also, our developing knowledge of the composition of early land-based ecosystems and the interactions among their various components is contributing to our understanding of how life on land affects key Earth Systems (e.g. carbon cycle). The emerging paradigm is one of early life on land dominated by microbes, small bryophyte-like organisms and lichens. Collectively called cryptogamic covers, these are comparable with those that dominate certain ecosystems today. This commentary was written to celebrate the 350th anniversary of the journal Philosophical Transactions of the Royal Society.

  9. Ecomorphology of radii in Canidae: Application to fragmentary fossils from Plio-Pleistocene hominin assemblages

    Directory of Open Access Journals (Sweden)

    Carlo Meloro

    2015-12-01

    Full Text Available Fragmentary long bone material from fossil Carnivora is rarely considered to support palaeoenvironmental reconstructions. Here, we use morphometry of the radius in extant carnivorans of the dog family (Canidae to reconstruct the palaeobiology of extinct canids from Olduvai Gorge, Tanzania (Bed I and II and Koobi Fora, Kenya. We use radius morphometrics to predict adaptation to prey size and introduce a new method for quantifying canid habitat adaptations based on the geographic distributions of the extant species sampled. Linear Discriminant Function Analyses (DFA and cluster neighbour-joining algorithms are employed to investigate radial morphometrics as described by 29 linear measurements. Results of our analyses suggest that a phylogenetic signal is present in radial morphometrics, even if it does not allow us to accurately discriminate among genera. A binary prey size categorisation of “small-medium” versus “large” prey can be more accurately predicted than a habitat categorisation scheme (Open, Mixed, Closed. The East African fossil specimens examined show morphometric affinities with the golden jackal (Canis aureus and coyote (Canis latrans and are likely attributable to the genus Canis. Fragmentary fossil specimens from Olduvai Gorge are predicted as habitat generalists (Open for Bed I and Mixed for Bed II adapted for hunting small-medium prey, whereas the specimen from Koobi Fora was predicted as inhabiting mixed habitats and adapted for killing large prey. This study supports the inclusion of fossil Canidae in palaeoecological analyses attempting to clarify the palaeoenvironment of early hominin fossil sites.

  10. Paleomycology of the Princeton Chert I. Fossil hyphomycetes associated with the early Eocene aquatic angiosperm, Eorhiza arnoldii.

    Science.gov (United States)

    Klymiuk, Ashley A; Taylor, Thomas N; Taylor, Edith L; Krings, Michael

    2013-01-01

    The Eocene (~ 48.7 Ma, Ypresian-Lutetian) Princeton Chert of British Columbia, Canada, has long been recognized as a significant paleobotanical locality, and a diverse assemblage of anatomically preserved fossil plants has been extensively documented. Co-occurring fossil fungi also have been observed, but the full scope of their diversity has yet to be comprehensively assessed. Here, we present the first of a series of investigations of fossilized fungi associated with the silicified plants of the Princeton Chert. This report focuses on saprotrophic, facultative-aquatic hyphomycetes observed in cortical aerenchyma tissue of an enigmatic angiosperm, Eorhiza arnoldii. Our use of paleontological thin sections provides the opportunity to observe and infer developmental features, making it possible to more accurately attribute two hyphomycetes that were observed in previous studies. These comprise multiseptate, holothallic, chlamydospore-like phragmoconidia most similar to extant Xylomyces giganteus and basipetal phragmospore-like chains of amerospores like those of extant Thielaviopsis basicola. We also describe a third hyphomycete that previously has not been recognized from this locality; biseptate, chlamydosporic phragmoconidia are distinguished by darkly melanized, inflated apical cells and are morphologically similar to Brachysporiella rhizoidea or Culcitalna achraspora.

  11. Deciphering the preservation of fossil insects: a case study from the Crato Member, Early Cretaceous of Brazil

    Directory of Open Access Journals (Sweden)

    Gabriel Ladeira Osés

    2016-12-01

    Full Text Available Exceptionally well-preserved three-dimensional insects with fine details and even labile tissues are ubiquitous in the Crato Member Konservat Lagerstätte (northeastern Brazil. Here we investigate the preservational pathways which yielded such specimens. We employed high resolution techniques (EDXRF, SR-SXS, SEM, EDS, micro Raman, and PIXE to understand their fossilisation on mineralogical and geochemical grounds. Pseudomorphs of framboidal pyrite, the dominant fossil microfabric, display size variation when comparing cuticle with inner areas or soft tissues, which we interpret as the result of the balance between ion diffusion rates and nucleation rates of pyrite through the originally decaying carcasses. Furthermore, the mineral fabrics are associated with structures that can be the remains of extracellular polymeric substances (EPS. Geochemical data also point to a concentration of Fe, Zn, and Cu in the fossils in comparison to the embedding rock. Therefore, we consider that biofilms of sulphate reducing bacteria (SRB had a central role in insect decay and mineralisation. Therefore, we shed light on exceptional preservation of fossils by pyritisation in a Cretaceous limestone lacustrine palaeoenvironment.

  12. Fossilization of feathers

    Science.gov (United States)

    Davis, Paul G.; Briggs, Derek E. G.

    1995-09-01

    Scanning electron microscopy of feathers has revealed evidence that a bacterial glycocalyx (a network of exocellular polysaccharide fibers) played a role in promoting their fossilization in some cases. This mode of preservation has not been reported in other soft tissues. The majority of fossil feathers are preserved as carbonized traces. More rarely, bacteria on the surface are replicated by authigenic minerals (bacterial autolithification). The feathers of Archaeopteryx are preserved mainly by imprintation following early lithification of the substrate and decay of the feather. Lacustrine settings provide the most important taphonomic window for feather preservation. Preservation in terrestrial and normal-marine settings involves very different processes (in amber and in authigenically mineralized coprolites, respectively). Therefore, there may be a significant bias in the avian fossil record in favor of inland water habitats.

  13. Fossil energy program. Progress report, July 1980

    Energy Technology Data Exchange (ETDEWEB)

    McNeese, L. E.

    1980-10-01

    This report - the seventy-second of a series - is a compendium of monthly progress reports for the ORNL research and development programs that are in support of the increased utilization of coal and other fossil fuel alternatives to oil and gas as sources of clean energy. The projects reported this month include those for coal conversion development, chemical research and development, materials technology, component development and process evaluation, technical support to major liquefaction projects, process and program analysis, fossil energy environmental analysis, coal preparation and waste utilization, coal preparation plant automation, atmospheric fluidized bed coal combustor for cogeneration, technical support to the TVA fluidized bed combustion demonstration plant program, fossil energy applications assessments, performance assurance system support for fossil energy projects, international assessment of atmospheric fluidized bed combustion technology, and PFBC systems analysis.

  14. A model for the spray zone in early-stage fluidized bed granulation

    NARCIS (Netherlands)

    Schaafsma, S. H.; Vonk, P.; Kossen, N. W. F.; Hoffmann, A. C.

    2006-01-01

    The formation of granules in the spray zone of a top-spray fluid-bed granulation process using a known and uniform drop-size is studied experimentally and theoretically. Experimental results indicate a multi-modal size distribution of spherically-shaped granules. A model is presented to explain this

  15. The origin of snakes: revealing the ecology, behavior, and evolutionary history of early snakes using genomics, phenomics, and the fossil record.

    Science.gov (United States)

    Hsiang, Allison Y; Field, Daniel J; Webster, Timothy H; Behlke, Adam D B; Davis, Matthew B; Racicot, Rachel A; Gauthier, Jacques A

    2015-05-20

    The highly derived morphology and astounding diversity of snakes has long inspired debate regarding the ecological and evolutionary origin of both the snake total-group (Pan-Serpentes) and crown snakes (Serpentes). Although speculation abounds on the ecology, behavior, and provenance of the earliest snakes, a rigorous, clade-wide analysis of snake origins has yet to be attempted, in part due to a dearth of adequate paleontological data on early stem snakes. Here, we present the first comprehensive analytical reconstruction of the ancestor of crown snakes and the ancestor of the snake total-group, as inferred using multiple methods of ancestral state reconstruction. We use a combined-data approach that includes new information from the fossil record on extinct crown snakes, new data on the anatomy of the stem snakes Najash rionegrina, Dinilysia patagonica, and Coniophis precedens, and a deeper understanding of the distribution of phenotypic apomorphies among the major clades of fossil and Recent snakes. Additionally, we infer time-calibrated phylogenies using both new 'tip-dating' and traditional node-based approaches, providing new insights on temporal patterns in the early evolutionary history of snakes. Comprehensive ancestral state reconstructions reveal that both the ancestor of crown snakes and the ancestor of total-group snakes were nocturnal, widely foraging, non-constricting stealth hunters. They likely consumed soft-bodied vertebrate and invertebrate prey that was subequal to head size, and occupied terrestrial settings in warm, well-watered, and well-vegetated environments. The snake total-group - approximated by the Coniophis node - is inferred to have originated on land during the middle Early Cretaceous (~128.5 Ma), with the crown-group following about 20 million years later, during the Albian stage. Our inferred divergence dates provide strong evidence for a major radiation of henophidian snake diversity in the wake of the Cretaceous-Paleogene (K

  16. Early and late lithification of aragonitic bivalve beds in the Purbeck Formation (upper jurassic-lower cretaceous) of Southern England

    Science.gov (United States)

    El-Shahat, Adam; West, Ian

    1983-05-01

    Beds of euryhaline bivalves alternating with shales constitute much of the middle Purbeck Formation. They originated on "tidal" flats at the western margin of an extensive brackish lagoon. When these shell beds are thin and enclosed in shale they are often still preserved as aragonite and are associated with "beef", fibrous calcite formed during compaction. In most cases, however, the shell debris has been converted by diagenesis into calcitic biosparrudite limestones. A compacted type has been lithified at a late stage, after deep burial. In this, pyrite is abundant and most of the shell aragonite has been replaced neomorphically by ferroan pseudopleochroic calcite. A contrasting uncompacted type of biosparrudite is characterised by bivalve fragments with micrite envelopes. Shells and former pores are occupied by non-ferroan sparry calcite cement, and there is little pyrite. These limestones frequently contain dinosaur footprints and originated in "supratidal" environments where they were cemented early, mainly in meteoric water. Once lithified they were unaffected by compaction. This uncompacted type indicates phases of mild uplift or halts in subsidence. These shell-bed lithologies, and also intermediate types described here, will probably be recognised in other lagoonal formations.

  17. Parameters determining the carbon isotopic composition of coal and fossil wood in the Early Miocene Oberdorf lignite seam (Styrian Basin, Austria)

    Energy Technology Data Exchange (ETDEWEB)

    Bechtel, A.; Sachsenhofer, R.F.; Gratzer, R.; Lucke, A.; Puttmann, W. [University of Leoben, Leoben (Austria)

    2002-07-01

    Petrographical and geochemical data of gelified and ungelified fossil wood from the Early Miocene Oberdorf lignite seam (Styrian Basin, Austria) provide evidence that the early diagenetic, aerobic degradation of wood by fungi may be followed by further decomposition under reducing conditions by the activity of anaerobic bacteria. Based on the molecular compositions of terpenoid hydrocarbons, the wood fragments in the lignite are identified as gymnosperms. The mean carbon isotope values found for gymnosperms and coals (-24.2 parts per thousand and -24.7 parts per thousand, respectively) confirm the results from biomarker analyses indicating that the peat-forming vegetation of the Oberdorf seam was dominated by gymnosperm taxa. The results obtained from the Early Miocene Oberdorf lignite indicate that the carbon isotope ratios of the coals are primarily affected by varying contributions of different parts of whole-plant tissue, due to their different isotopic and molecular compositions (e.g. epicuticular leaf waxes, resins, wood) and their different decay-resistance against the early diagenetic changes involved in organic matter decomposition. Carbon cycling during anoxic decomposition of plant-derived organic matter is assumed to affect the {delta}-{sup 13}C values of coal. {delta}-{sup 13}C Values of wood and extracted cellulose are affected only to a minor extent.

  18. Early evolution of life cycles in embryophytes:A focus on the fossil evidence of gametophyte/sporophyte size and morphological complexity

    Institute of Scientific and Technical Information of China (English)

    Philippe GERRIENNE; Paul GONEZ

    2011-01-01

    Embryophytes (land plants) are distinguished from their green algal ancestors by diplobiontic life cycles,that is,alternation of multicellular gametophytic and sporophytic generations.The bryophyte sporophyte is small and matrotrophic on the dominant gametophyte; extant vascular plants have an independent,dominant sporophyte and a reduced gametophyte.The elaboration of the diplobiontic life cycle in embryophytes has been thoroughly discussed within the context of the Antithetic and the Homologous Theories.The Antithetic Theory proposes a green algal ancestor with a gametophyte-dominant haplobiontic life cycle.The Homologous Theory suggests a green algal ancestor with alternation of isomorphic generations.The shifts that led from haplobiontic to diplobiontic life cycles and from gametophytic to sporophytic dominance are most probably related with terrestrial habitats.Cladistic studies strongly support the Antithetic Theory in repeatedly identifying charophycean green algae as the closest relatives of land plants.In recent years,exceptionally well-preserved axial gametophytes have been described from the Rhynie chert (Lower Devonian,410 Ma),and the complete life cycle of several Rhynie chert plants has been reconstructed.All show an alternation of more or less isomorphic generations,which is currently accepted as the plesiomorphic condition among all early polysporangiophytes,including basal tracheophytes.Here we review the existing evidence for early embryophyte gametophytes.We also discuss some recently discovered plants preserved as compression fossils and interpreted as gametophytes.All the fossil evidence supports the Antithetic Theory and indicates that the gametophytic generation/sporophytic generation size and complexity ratios show a gradual decrease along the land plant phylogenetic tree.

  19. Early development of rostrum saw-teeth in a fossil ray tests classical theories of the evolution of vertebrate dentitions.

    Science.gov (United States)

    Smith, Moya Meredith; Riley, Alex; Fraser, Gareth J; Underwood, Charlie; Welten, Monique; Kriwet, Jürgen; Pfaff, Cathrin; Johanson, Zerina

    2015-10-07

    In classical theory, teeth of vertebrate dentitions evolved from co-option of external skin denticles into the oral cavity. This hypothesis predicts that ordered tooth arrangement and regulated replacement in the oral dentition were also derived from skin denticles. The fossil batoid ray Schizorhiza stromeri (Chondrichthyes; Cretaceous) provides a test of this theory. Schizorhiza preserves an extended cartilaginous rostrum with closely spaced, alternating saw-teeth, different from sawfish and sawsharks today. Multiple replacement teeth reveal unique new data from micro-CT scanning, showing how the 'cone-in-cone' series of ordered saw-teeth sets arrange themselves developmentally, to become enclosed by the roots of pre-existing saw-teeth. At the rostrum tip, newly developing saw-teeth are present, as mineralized crown tips within a vascular, cartilaginous furrow; these reorient via two 90° rotations then relocate laterally between previously formed roots. Saw-tooth replacement slows mid-rostrum where fewer saw-teeth are regenerated. These exceptional developmental data reveal regulated order for serial self-renewal, maintaining the saw edge with ever-increasing saw-tooth size. This mimics tooth replacement in chondrichthyans, but differs in the crown reorientation and their enclosure directly between roots of predecessor saw-teeth. Schizorhiza saw-tooth development is decoupled from the jaw teeth and their replacement, dependent on a dental lamina. This highly specialized rostral saw, derived from diversification of skin denticles, is distinct from the dentition and demonstrates the potential developmental plasticity of skin denticles. © 2015 The Authors.

  20. Jianshangou Bed of the Yixian Formation in West Liaoning, China

    Institute of Scientific and Technical Information of China (English)

    CHEN; Peiji; WANG; Qifei; ZHANG; Haichun; GAO; Meizhen; LI

    2005-01-01

    The Jianshangou Bed is a set of fossil-bearing sedimentary interlayers of the basal volcano-sedimentary deposits of Yixian Formation in western Liaoning. It is rich in volcanic composition and consists of upper and lower grey-black shale, basal sandy conglomerate, top tuffaceous sandstone, middle massive silty mudstone and siltstone, as well as andesite, with a thickness of 28-95 m. The Jianshangou Bed is famous all over the world for its bearing early birds, angiosperms and feathered dinosaurs, and it also yields bivalves, gastropods, conchostracans, ostracods, shrimps, insects, fish, amphibians, primitive mammals and other reptiles.These fossils are typical representatives of the Late Mesozoic Jehol Biota from eastern Asia. The Chaomidianzi and Sihetun formations, proposed in recent years, are regarded as the junior synonyms of the Jianshangou Bed. The Jehol Biota is endemic to eastern Asia, however, it has a large geographic distribution, more than half of the European territory. Many species of the biota have close relationships with the late Jurassic European counterparts, e.g. both Confuciusornis and Archaeopteryx are primitive birds, Sinosauropteryx has a similar skeleton construction with Compsognathus, the ostracode assemblage from the Jianshangou Bed is close to that from the Purbeck Bed in England, and Aeschnidium occurs in both the Jianshangou Bed and Solnhofen of Germany. Based on the biostratigraphic correlation, the Jianshangou Bed is more probably late Tithonian in age. The latest zircon U-Pb dating of the Jianshangou Bed gives 125.2 Ma, and is close to the feldspar Ar/Ar dating of 124.6 Ma. A glauconite dating of 125 Ma was once got from England near the J/K boundary within the Purbeck Bed, so it is still problematic to place the J/K boundary at 130, 135, 137, 142 or 145.5 Ma in the International Stratigraphic Charts.

  1. Paleoredoc and pyritization of soft-bodied fossils in the Ordovician Frankfort Shale of New York

    DEFF Research Database (Denmark)

    Farrell, Una C.; Briggs, Derek E. G.; Hammarlund, Emma U.

    2013-01-01

    Multiple beds in the Frankfort Shale (Upper Ordovician, New York State), including the original "Beecher's Trilobite Bed," yield fossils with pyritized soft-tissues. A bed-by-bed geochemical and sedimentological analysis was carried out to test previous models of soft-tissue pyritization by inves......Multiple beds in the Frankfort Shale (Upper Ordovician, New York State), including the original "Beecher's Trilobite Bed," yield fossils with pyritized soft-tissues. A bed-by-bed geochemical and sedimentological analysis was carried out to test previous models of soft-tissue pyritization...

  2. Are the oldest 'fossils', fossils

    Science.gov (United States)

    Schopf, J. W.

    1976-01-01

    A comparative statistical study has been carried out on populations of modern algae, Precambrian algal microfossils, the 'organized elements' of the Orgueil carbonaceous meteorite, and the oldest microfossil-like objects now known (spheroidal bodies from the Fig Tree and Onverwacht Groups of the Swaziland Supergroup, South Africa). The distribution patterns exhibited by the more than 3000 m.y.-old Swaziland microstructures bear considerable resemblance to those of the abiotic 'organized elements' but differ rather markedly from those exhibited by younger, assuredly biogenic, populations. Based on these comparisons, it is concluded that the Swaziland spheroids could be, at least in part, of nonbiologic origin; these oldest known fossil-like microstructures should not be regarded as constituting firm evidence of Archean life.

  3. Discovery of Corallina fossil from the Middle Cambrian of Taijiang County,Guizhou Province,China

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Abundant and well-preserved macroalgae fossils have been discovered in silty mudstones and shales from the Middle Cambrian of Taijiang County,Guizhou Province,China.Corallina Paraamphiroa siniansis gen.et sp.nov.in the Kaili Fm.,is the earliest Corallina fossil,which usually coexists with other carbonaceous macroalgae fossils on the bedding planes of mudstone and shale and is different from the calcareous and phosphatized Precambrian-Cambrian thallus discovered in the Lower Cambrian of Siberia and the Doushantou phosphate rocks of Weng'an County,Guizhou Province,China.The discovery of calcified thallus in the Kaili Fm.bears great importance on the study of phylogeny and evolution of early calcareous macroalgae.

  4. Early processing variations in selective attention to the color and direction of moving stimuli during 30 days head-down bed rest

    Science.gov (United States)

    Wang, Lin-Jie; He, Si-Yang; Niu, Dong-Bin; Guo, Jian-Ping; Xu, Yun-Long; Wang, De-Sheng; Cao, Yi; Zhao, Qi; Tan, Cheng; Li, Zhi-Li; Tang, Guo-Hua; Li, Yin-Hui; Bai, Yan-Qiang

    2013-11-01

    Dynamic variations in early selective attention to the color and direction of moving stimuli were explored during a 30 days period of head-down bed rest. Event-related potentials (ERPs) were recorded at F5, F6, P5, P6 scalp locations in seven male subjects who attended to pairs of bicolored light emitting diodes that flashed sequentially to produce a perception of movement. Subjects were required to attend selectively to a critical feature of the moving target, e.g., color or direction. The tasks included: a no response task, a color selective response task, a moving direction selective response task, and a combined color-direction selective response task. Subjects were asked to perform these four tasks on: the 3rd day before bed rest; the 3rd, 15th and 30th day during the bed rest; and the 5th day after bed rest. Subjects responded quickly to the color than moving direction and combined color-direction response. And they had a longer reaction time during bed rest on the 15th and 30th day during bed rest after a relatively quicker response on the 3rd day. Using brain event-related potentials technique, we found that in the color selective response task, the mean amplitudes of P1 and N1 for target ERPs decreased in the 3rd day during bed rest and 5th day after bed rest in comparison with pre-bed rest, 15th day and 30th day during bed rest. In the combined color-direction selective response task, the P1 latencies for target ERPs on the 3rd and 30th day during bed rest were longer than on the 15th day during bed rest. As 3rd day during bed rest was in the acute adaptation period and 30th day during bed rest was in the relatively adaptation stage of head-down bed rest, the results help to clarify the effects of bed rest on different task loads and patterns of attention. It was suggested that subjects expended more time to give correct decision in the head-down tilt bed rest state. A difficulty in the recruitment of brain resources was found in feature selection task

  5. The Pleistocene archaeology and environments of the Wasiriya Beds, Rusinga Island, Kenya.

    Science.gov (United States)

    Tryon, Christian A; Tyler Faith, J; Peppe, Daniel J; Fox, David L; McNulty, Kieran P; Jenkins, Kirsten; Dunsworth, Holly; Harcourt-Smith, Will

    2010-12-01

    Western Kenya is well known for abundant early Miocene hominoid fossils. However, the Wasiriya Beds of Rusinga Island, Kenya, preserve a Pleistocene sedimentary archive with radiocarbon age estimates of >33-45 ka that contains Middle Stone Age artifacts and abundant, well-preserved fossil fauna: a co-occurrence rare in eastern Africa, particularly in the region bounding Lake Victoria. Artifacts and fossils are associated with distal volcanic ash deposits that occur at multiple localities in the Wasiriya Beds, correlated on the basis of geochemical composition as determined by electron probe microanalysis. Sediment lithology and the fossil ungulates suggest a local fluvial system and associated riparian wooded habitat within a predominantly arid grassland setting that differs substantially from the modern environment, where local climate is strongly affected by moisture availability from Lake Victoria. In particular, the presence of oryx (Oryx gazella) and Grevy's zebra (Equus grevyi) suggest a pre-Last Glacial Maximum expansion of arid grasslands, an environmental reconstruction further supported by the presence of several extinct specialized grazers (Pelorovis antiquus, Megalotragus sp., and a small alcelaphine) that are unknown from Holocene deposits in eastern Africa. The combination of artifacts, a rich fossil fauna, and volcaniclastic sediments makes the Wasiriya Beds a key site for examining the Lake Victoria basin, a biogeographically important area for understanding the diversification and dispersal of Homo sapiens from Africa, whose pre-Last Glacial Maximum history remains poorly understood. Copyright © 2010 Elsevier Ltd. All rights reserved.

  6. Undesirable dispersal of eggs and early-stage nymphs of the bed bug Hemiptera: cimicidae) by static electricity and air currents

    Science.gov (United States)

    Movement of whole live insects or other small arthropods attributed to static electricity has been reported only rarely. While viewing bed bugs in plastic or glass Petri dishes using a dissecting microscope, individual eggs and early stage nymphs were occasionally observed to move suddenly and rapid...

  7. Rhizopalmoxylon nypoides - a new palm root from the Deccan Intertrappean beds of Sagar, Madhya Pradesh, India

    Science.gov (United States)

    Kathal, P. K.; Srivastava, Rashmi; Mehrotra, R. C.; Alexander, P. O.

    2017-04-01

    A new species of fossil palm rhizome having root-mat under the organ genus Rhizopalamoxylon ( Rhizopalmoxylon nypoides sp. nov.) is reported. The specimen shows the closest resemblance with the modern monotypic genus Nypa Wurmb of the Arecaceae. The specimen was collected from the late Maastrichtian-early Danian sediments of Deccan Intertrappean beds, Mothi, Sagar district, Madhya Pradesh, India. Nypa is a mangrove palm naturally found in estuaries and swamps of the tropical region and represents one of the oldest records of the genus from the Deccan Intertrappean beds of central India. The abundance of palms, including Nypa and previously recorded coastal and mangrove elements such as Acrostichum, Barringtonia, Cocos, Sonneratia and marine algae ( Distichoplax and Peyssonellia) from the Deccan Intertrappean beds indicate marine influence and existence of tropical rainforest ecosystem in the vicinity of fossil locality in contrast to the deciduous forests occurring there at present.

  8. Changing the picture of Earth's earliest fossils (3.5-1.9 Ga) with new approaches and new discoveries.

    Science.gov (United States)

    Brasier, Martin D; Antcliffe, Jonathan; Saunders, Martin; Wacey, David

    2015-04-21

    New analytical approaches and discoveries are demanding fresh thinking about the early fossil record. The 1.88-Ga Gunflint chert provides an important benchmark for the analysis of early fossil preservation. High-resolution analysis of Gunflintia shows that microtaphonomy can help to resolve long-standing paleobiological questions. Novel 3D nanoscale reconstructions of the most ancient complex fossil Eosphaera reveal features hitherto unmatched in any crown-group microbe. While Eosphaera may preserve a symbiotic consortium, a stronger conclusion is that multicellular morphospace was differently occupied in the Paleoproterozoic. The 3.46-Ga Apex chert provides a test bed for claims of biogenicity of cell-like structures. Mapping plus focused ion beam milling combined with transmission electron microscopy data demonstrate that microfossil-like taxa, including species of Archaeoscillatoriopsis and Primaevifilum, are pseudofossils formed from vermiform phyllosilicate grains during hydrothermal alteration events. The 3.43-Ga Strelley Pool Formation shows that plausible early fossil candidates are turning up in unexpected environmental settings. Our data reveal how cellular clusters of unexpectedly large coccoids and tubular sheath-like envelopes were trapped between sand grains and entombed within coatings of dripstone beach-rock silica cement. These fossils come from Earth's earliest known intertidal to supratidal shoreline deposit, accumulated under aerated but oxygen poor conditions.

  9. A Multi-Institutional Study of Feasibility, Implementation, and Early Clinical Results With Noninvasive Breast Brachytherapy for Tumor Bed Boost

    Energy Technology Data Exchange (ETDEWEB)

    Hamid, Subarna, E-mail: shamid@tuftsmedicalcenter.org [Department of Radiation Oncology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA (United States); Department of Radiation Oncology, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, RI (United States); Rocchio, Kathy [Department of Radiation Oncology, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, RI (United States); Arthur, Douglas; Vera, Robyn [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, VA (United States); Sha, Sandra; Jolly, Michele [Central Florida Cancer Institute, Davenport, FL (United States); Cavanaugh, Sean; Wooten, Eric [Atlanta Oncology Associates, Hawkinsville, GA (United States); Benda, Rashmi; Greenfield, Brad [Department of Radiation Oncology, Boca Raton Community Hospital, Boca Raton, FL (United States); Prestidge, Bradley [Texas Cancer Clinic, San Antonio, TX (United States); Ackerman, Scot [First Coast Oncology, Jacksonville, FL (United States); Kuske, Robert; Quiet, Coral; Snyder, Margaret [Arizona Breast Cancer Specialists, Phoenix, AZ (United States); Wazer, David E. [Department of Radiation Oncology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA (United States); Department of Radiation Oncology, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, RI (United States)

    2012-08-01

    Purpose: To evaluate the feasibility, implementation, and early results of noninvasive breast brachytherapy (NIBB) for tumor bed boost with whole breast radiation therapy (WBRT). Methods and Materials: NIBB is a commercially available (AccuBoost, Billerica, MA) mammography-based, brachytherapy system in which the treatment applicators are centered on the planning target volume (PTV) to direct {sup 192}Ir emissions along orthogonal axes. A privacy-encrypted online data registry collected information from 8 independent academic and community-based institutions. Data were from 146 consecutive women with early-stage breast cancer after lumpectomy and WBRT receiving boost with NIBB between July 2007 and March 2010. Toxicity and cosmesis were graded according to the Common Toxicity Criteria (v. 3.0) and the Harvard scale. Median follow-up was 6 months (1-39 months). Results: Grade 1-2 skin toxicity was observed in 64%, 48%, and 21% during the acute (1-3 weeks), intermediate (4-26 weeks), and late-intermediate (>26 weeks) periods. There was no Grade 4 toxicity. At 6 months, for the entire cohort, cosmesis was excellent/good in 62%/38%. The subset receiving NIBB before WBRT had cosmetic scores of 32% and 63%, whereas during WBRT, 58% and 37% were rated as excellent and good, respectively. Breast compression was scored as 'uncomfortable' in 12%, 29%, and 59% when NIBB was delivered before, during, or after WBRT. For each patient, the fraction-to-fraction variability in PTV was low. Skin flash was associated with a higher proportion of excellent cosmesis (58% vs. 42%) relative to having the applicator all within breast tissue. Conclusions: These data indicate that NIBB is feasible and can be consistently implemented in a broad array of practice settings. Preliminary evaluation suggests that NIBB is associated with acceptably mild normal tissue toxicity and favorable early cosmesis. The application of NIBB before WBRT may be associated with better patient tolerance

  10. Bed Bugs

    Science.gov (United States)

    Prevent, identify, and treat bed bug infestations using EPA’s step-by-step guides, based on IPM principles. Find pesticides approved for bed bug control, check out the information clearinghouse, and dispel bed bug myths.

  11. Ediacaran Macro Body Fossils

    OpenAIRE

    Huang, Timothy D.; Jei-Fu Shaw; Liang Zheng; Chun-Lan Huang; YiLung Chang; ChuanWei Yang

    2010-01-01

    This paper, Ediacaran Macro Body Fossils, reports a new discovery of well preserved three dimensional macro body fossils of the Ediacaran Period in central YunNan province in the People's Republic of China. These body fossils will enable more detailed and in-depth exploration of the evolution of multi-cellular macro organisms on this planet, whereas in the past, researches could only rely on cast or imprint fossils.

  12. The Fossile Episode

    OpenAIRE

    Hassler, John; Sinn, Hans-Werner

    2012-01-01

    We build a two-sector dynamic general equilibrium model with one-sided substitutability between fossil carbon and biocarbon. One shock only, the discovery of the technology to use fossil fuels, leads to a transition from an inital pre-industrial phase to three following phases: a pure fossil carbon phase, a mixed fossil and biocarbon phase and an absorbing biocarbon phase. The increased competition for biocarbon during phase 3 and 4 leads to increasing food prices. We provide closed form expr...

  13. The Fossil Episode

    OpenAIRE

    Hassler, John; Sinn, Hans-Werner

    2012-01-01

    We build a two-sector dynamic general equilibrium model with one-sided substitutability between fossil carbon and biocarbon. One shock only, the discovery of the technology to use fossil fuels, leads to a transition from an initial pre-industrial phase to three following phases: a pure fossil carbon phase, a mixed fossil and biocarbon phase and an absorbing biocarbon phase. The increased competition for biocarbon during phase 3 and 4 leads to increasing food prices. We provide closed form exp...

  14. 贵州早-中寒武世凯里组类似苔藓植物化石%Bryophyte-like Fossil (Parafunaria sinensis) from Early-Middle Cambrian Kaili Formation in Guizhou Province,China

    Institute of Scientific and Technical Information of China (English)

    杨瑞东; 毛家仁; 张位华; 姜立君; 高慧

    2004-01-01

    Abundant well-preserved animal and macroalgal fossils were discovered in the Early-Middle Cambrian Kaili Formation of Taijiang County, Guizhou Province, China, which constitute the Kaili Biota,named as one of the three important Burgess Shale-type faunas. The bryophyte-like fossil (Parafunaria sinensis Yang gen. et sp. nov) was discovered in the horizon of occurrence of Macroalgal fossils. The fossil of P. sinensis possesses typical characters of bryophyte, such as whorled leaves, capsule and seta, and complex rhizoid or foot. We infer that the bryophyte-like fossil could be the ancestor of bryophyte. The discovery provides a new lead for further study on the origin and evolution of bryophyte or land plant.%贵州台江早-中寒武世凯里组保存大量的生物化石,它构成了寒武纪重要的生物群之一--凯里生物群.在凯里生物群中保存有丰富的碳质薄膜藻类化石,新发现类似苔藓植物化石(Parafunaria sinensis Yang(gen.et sp.nov)),它具有藓类植物所拥有的典型的叶状体轮生现象、孢朔、孢朔柄和复杂的根系特征.推测它是藓类植物祖先,它为进一步研究藓类植物和陆生高等植物的起源和演化提供了新的线索.

  15. The taphonomy of unmineralised Palaeozoic fossils preserved as siliciclastic moulds and casts, and their utility in assessing the interaction between environmental change and the fossil record

    Science.gov (United States)

    MacGabhann, Breandán; Schiffbauer, James; Hagadorn, James; Van Roy, Peter; Lynch, Edward; Morrsion, Liam; Murray, John

    2015-04-01

    The enhanced preservation potential of biomineralised tissues in fossil organisms is a key factor in their utility in the investigation of palaeoenvironmental change on fossil ecosystems. By contrast, the considerably lower preservation potential of entirely unmineralised organisms severely reduces the utility of their temporal and spatial distribution in such analyses. However, understanding the taphonomic processes which lead to the preservation of such soft-bodied fossils may be an under-appreciated source of information, particularly in the case of specimens preserved as moulds and casts in coarser siliciclastic sediments. This information potential is well demonstrated by fossil eldonids, a Cambrian to Devonian clade of unmineralised asymmetrical discoidal basal or stem deuterostomes, with an apparently conservative biology and no clear palaeoenvironmental or biogeographical controls on their distribution. We investigated the taphonomic processes involved in the preservation of fossil eldonids as moulds and casts on bedding surfaces and within event beds from sandstones of the Ordovician Tafilalt lagerstätte in south-eastern Morocco, and from siltstones of the Devonian West Falls Group of New York, USA. Laser Raman microspectroscopy, SEM BSE imaging and EDS elemental mapping of fossil specimens reveals that moulded biological surfaces are coated by a fossil surface veneer primarily consisting of mixed iron oxides and oxyhydroxides (including pseudomorphs after pyrite), and aluminosilicate clay minerals. Moreover, comparison to fossil eldonids preserved as carbonaceous compressions in the Burgess Shale reveals that the biological structures preserved in the Tafilalt and New York specimens - the dorsal surface and a coiled sac containing the digestive tract - represent only specific portions of the anatomy of the complete animal. We suggest that the preserved remains were the only parts of these eldonid organisms composed primarily of complex organic

  16. Rhizopalmoxylon nypoides – a new palm root from the Deccan Intertrappean beds of Sagar, Madhya Pradesh, India

    Indian Academy of Sciences (India)

    P K Kathal; Rashmi Srivastava; R C Mehrotra; P O Alexander

    2017-04-01

    A new species of fossil palm rhizome having root-mat under the organ genus Rhizopalamoxylon (Rhizopalmoxylon nypoides sp. nov.) is reported. The specimen shows the closest resemblance with the modern monotypic genus Nypa Wurmb of the Arecaceae. The specimen was collected from the late Maastrichtian–early Danian sediments of Deccan Intertrappean beds, Mothi, Sagar district, Madhya Pradesh, India. Nypa is a mangrove palm naturally found in estuaries and swamps of the tropical region and represents one of the oldest records of the genus from the Deccan Intertrappean beds of centralIndia. The abundance of palms, including Nypa and previously recorded coastal and mangrove elementssuch as Acrostichum, Barringtonia, Cocos, Sonneratia and marine algae (Distichoplax and Peyssonellia)from the Deccan Intertrappean beds indicate marine influence and existence of tropical rainforestecosystem in the vicinity of fossil locality in contrast to the deciduous forests occurring there at present.

  17. UNMINERALIZED FOSSIL BACTERIA.

    Science.gov (United States)

    BRADLEY, W H

    1963-09-06

    Unmineralized bacterial cells, mostly Micrococcus sp., but including also Streptococcus sp. and Actinomyces sp., were found in enormous numbers in lake beds of the Newark Canyon Formation of Early Cretaceous age, Eureka County, Nevada. The micrococci are black, and have an average diameter about 0.5 micro. Similar black micrococci (0.4 to 0.7 micro) were found in profusion in the bottom mud of Green Lake, New York. About 80 percent of this mud consists of minute idiomorphic calcite crystals and about 20 percent of these contain enormous numbers of the black micrococci. It is suggested that the Early Cretaceous bacterial cells owe their preservation to occlusion in calcite crystals that grew in a black, bacterial mud in a meromictic lake in which part of the Newark Canyon Formation accumulated.

  18. Reworked pyroclastic beds in the early Miocene of Patagonia: Reaction in response to high sediment supply during explosive volcanic events

    Science.gov (United States)

    Cuitiño, José I.; Scasso, Roberto A.

    2013-05-01

    Two meter-scale pyroclastic levels are interbedded within the early Miocene succession of the Estancia 25 de Mayo (Patagoniense transgression) and Santa Cruz formations in the foreland Austral (or Magallanes) Basin, Argentina. The Lower Pyroclastic Level (LPL) is a tabular body interbedded within offshore marine deposits, laterally continuous for 30 km and varying in thickness from few centimeters to around 4 m. Grain-size grades from coarse to extremely fine ash with upward-fining along with a northeastern-fining trends. Structureless fine to very fine tuffs dominate and rare parallel laminations are the only tractive sedimentary structures. The Upper Pyroclastic Level (UPL) lies within low energy fluvial deposits and is laterally discontinuous, and it is composed by lenticular bodies reaching a maximum of 15 m thick and 100 m wide, with a concave-up base and a plane top. Grain-size range is similar to the LPL but it coarsens upward. The lower portion of the UPL shows parallel lamination, current ripple lamination and mud drapes with large pumice lapilli and plant debris, whereas the upper portion shows parallel lamination and trough cross-stratification. Both pyroclastic levels are composed mainly of pumice grains and glass shards with minor proportions of quartz and plagioclase crystals and lithic fragments. The LPL shows no mixing with epiclastic material whereas the UPL shows an upward increase in epiclastic material, and an upward increment in the scale of cross-bedding. The large thickness in relation to the possible emission center and the content of plant debris of the LPL does not suggest a direct, submarine, ash-fallout origin. The LPL is interpreted as a deposit of hyperpycnal-flows generated at the coastal zone when tephra-laden rivers plunged into the ocean. Large amounts of well preserved plant debris support the hypothesis of a terrestrial source of the sediments. The UPL is entirely composed of tractive deposits, so an ash fallout origin is

  19. Geo(Im)pulseBite marks on early Holocene Tursiops truncatus fossils from the North Sea indicate scavenging by rays (Chondrichthyes, Rajidae)

    NARCIS (Netherlands)

    Netten, H.H. van; Reumer, J.W.F.

    2010-01-01

    A number of Tursiops truncatus mandibles in the collection of fossil marine mammals in the Rotterdam Natural History Museum have marks consisting of several parallel linear grooves. These marks are also found on four atlas complexes, a scapula and on one vertebra. The hypothesis that they are bite m

  20. Fossil Group Origins VII. Galaxy substructures in fossil systems

    CERN Document Server

    Zarattini, S; Aguerri, J A L; Boschin, W; Barrena, R; del Burgo, C; Castro-Rodriguez, N; Corsini, E M; D'Onghia, E; Kundert, A; Méndez-Abreu, J; Sánchez-Janssen, R

    2016-01-01

    Fossil groups are expected to be the final product of galaxy merging within galaxy groups. In simulations, they are predicted to assemble their mass at high redshift. This early formation allows for the innermost $M^\\ast$ galaxies to merge into a massive central galaxy. Then, they are expected to maintain their fossil status because of the few interactions with the large-scale structure. In this context, the magnitude gap between the two brightest galaxies of the system is considered a good indicator of its dynamical status. As a consequence, the systems with the largest gaps should be dynamically relaxed. In order to examine the dynamical status of these systems, we systematically analyze, for the first time, the presence of galaxy substructures in a sample of 12 spectroscopically-confirmed fossil systems with redshift $z \\le 0.25$. We apply a number of tests in order to investigate the substructure in fossil systems in the two-dimensional space of projected positions out to $R_{200}$. Moreover, for a subsam...

  1. X-ray computed tomography datasets for forensic analysis of vertebrate fossils.

    Science.gov (United States)

    Rowe, Timothy B; Luo, Zhe-Xi; Ketcham, Richard A; Maisano, Jessica A; Colbert, Matthew W

    2016-06-07

    We describe X-ray computed tomography (CT) datasets from three specimens recovered from Early Cretaceous lakebeds of China that illustrate the forensic interpretation of CT imagery for paleontology. Fossil vertebrates from thinly bedded sediments often shatter upon discovery and are commonly repaired as amalgamated mosaics grouted to a solid backing slab of rock or plaster. Such methods are prone to inadvertent error and willful forgery, and once required potentially destructive methods to identify mistakes in reconstruction. CT is an efficient, nondestructive alternative that can disclose many clues about how a specimen was handled and repaired. These annotated datasets illustrate the power of CT in documenting specimen integrity and are intended as a reference in applying CT more broadly to evaluating the authenticity of comparable fossils.

  2. The First Observation on Plant Cell Fossils in China

    Institute of Scientific and Technical Information of China (English)

    WANG Xin; CUI Jinzhong

    2007-01-01

    For a long time, paleontologists have been focusing on hard parts of organisms during different geological periods while soft parts are rarely reported. Well-preserved plant cells, if found in fossils, are treated only as a rarity. Recent progress in research on fossil cytoplasm indicates that plant cytoplasm not only has excellent ultrastructures preserved but also may be a quite commonly seen fossil in strata. However, up to now there is no report of plant cell fossils in China yet. Here plant cell fossils are reported from Huolinhe Coal Mine (the early Cretaceous), Inner Mongolia, China. The presence of plant cytoplasm fossils in two cones on the same specimen not only provides further support for the recently proposed hypothesis on plant cytoplasm fossilization but also marks the first record of plant cytoplasm fossils in China, which suggests a great research potential in this new area.

  3. The early evolution of land plants, from fossils to genomics: a commentary on Lang (1937) ‘On the plant-remains from the Downtonian of England and Wales'

    Science.gov (United States)

    Edwards, Dianne; Kenrick, Paul

    2015-01-01

    During the 1920s, the botanist W. H. Lang set out to collect and investigate some very unpromising fossils of uncertain affinity, which predated the known geological record of life on land. His discoveries led to a landmark publication in 1937, ‘On the plant-remains from the Downtonian of England and Wales’, in which he revealed a diversity of small fossil organisms of great simplicity that shed light on the nature of the earliest known land plants. These and subsequent discoveries have taken on new relevance as botanists seek to understand the plant genome and the early evolution of fundamental organ systems. Also, our developing knowledge of the composition of early land-based ecosystems and the interactions among their various components is contributing to our understanding of how life on land affects key Earth Systems (e.g. carbon cycle). The emerging paradigm is one of early life on land dominated by microbes, small bryophyte-like organisms and lichens. Collectively called cryptogamic covers, these are comparable with those that dominate certain ecosystems today. This commentary was written to celebrate the 350th anniversary of the journal Philosophical Transactions of the Royal Society. PMID:25750238

  4. Shell Bed Identification of Kaliwangu Formation and its Sedimentary Cycle Significance, Sumedang, West Java

    Directory of Open Access Journals (Sweden)

    Aswan Aswan

    2014-07-01

    Full Text Available DOI: 10.17014/ijog.v8i1.151Kaliwangu Formation cropping out around Sumedang area contains mollusk fossils dominated by gastropods and bivalves. In terms of sequence stratigraphy, each sedimentary cycle generally consists of four shell bed types: Early Transgressive Systems Tract (Early TST deposited above an erosional surface or sequence boundary, that is characterized by shell disarticulation, trace fossils, gravelly content, no fossil orientation direction, and concretion at the bottom; Late Transgressive Systems Tract (Late TST identified by articulated (conjoined specimen in its life position, that shows a low level abration and fragmentation, adult specimen with complete shells, and variation of taxa; Early Highstand Systems Tract (Early HST characterized by adult taxa that was found locally in their life position with individual articulation, juvenile specimens frequently occured; Late Highstand Systems Tract (Late HST determined as multiple-event concentrations, disarticulated shell domination, and some carbon or amber intercalation indicating terrestrial influence. Shell bed identification done on this rock unit identified nineteen sedimentary cycles.

  5. Shell Bed Identification of Kaliwangu Formation and its Sedimentary Cycle Significance, Sumedang, West Java

    Directory of Open Access Journals (Sweden)

    Aswan Aswan

    2014-07-01

    Full Text Available DOI: 10.17014/ijog.v8i1.151Kaliwangu Formation cropping out around Sumedang area contains mollusk fossils dominated by gastropods and bivalves. In terms of sequence stratigraphy, each sedimentary cycle generally consists of four shell bed types: Early Transgressive Systems Tract (Early TST deposited above an erosional surface or sequence boundary, that is characterized by shell disarticulation, trace fossils, gravelly content, no fossil orientation direction, and concretion at the bottom; Late Transgressive Systems Tract (Late TST identified by articulated (conjoined specimen in its life position, that shows a low level abration and fragmentation, adult specimen with complete shells, and variation of taxa; Early Highstand Systems Tract (Early HST characterized by adult taxa that was found locally in their life position with individual articulation, juvenile specimens frequently occured; Late Highstand Systems Tract (Late HST determined as multiple-event concentrations, disarticulated shell domination, and some carbon or amber intercalation indicating terrestrial influence. Shell bed identification done on this rock unit identified nineteen sedimentary cycles.

  6. Geo(Im)pulseBite marks on early Holocene Tursiops truncatus fossils from the North Sea indicate scavenging by rays (Chondrichthyes, Rajidae)

    OpenAIRE

    Netten, H.H. van; Reumer, J.W.F.

    2010-01-01

    A number of Tursiops truncatus mandibles in the collection of fossil marine mammals in the Rotterdam Natural History Museum have marks consisting of several parallel linear grooves. These marks are also found on four atlas complexes, a scapula and on one vertebra. The hypothesis that they are bite marks and were caused by scavenging rays (Rajidae, Chondrichthyes) was tested with a real-life experiment using different shark and ray species, allowing them to scavenge on cow ribs as proxies for ...

  7. Factors contributing to fossilization

    Institute of Scientific and Technical Information of China (English)

    徐菁

    2010-01-01

    As the most prominent feature of interlanguage, fossilization is a complex and essential topic in the field of SLA research. Various causes, in spite quantity of them are only theories, have been studied by different researchers from multiple points of view. Daiwei Dong(1990) has pointed out that virtually every inaccurate cause leads to language fossilization. This paper tries to conclude update causes of fossilization.

  8. Stratigraphy and age of the Daohugou Bed in Ningcheng, Inner Mongolia

    Institute of Scientific and Technical Information of China (English)

    WANG Xiaolin; ZHOU Zhonghe; HE Huaiyu; JIN Fan; WANG Yuanqing; ZHANG Jiangyong; WANG Yuan; XU Xing; ZHANG Fucheng

    2005-01-01

    Recent fieldwork has extended the distribution of the Daohugou Bed deposits from the Daohugou Village to its several neighboring areas. The fossil-bearing Daohugou deposits uncomformably overlie complex bedrocks, and comprise three major parts. The red shales in the lower part were misidentified as belonging to the Tuchengzi Formation. Field excavation has indicated that the shales of upper part of the bed are the major fossil-bearing horizon. Due to strong tectonic activities, sediments were often folded with the sequences inverted in the region. Some newly recognized contacts between the Daohugou Bed and the volcanic rocks showed that the ignimbrite of the Tiaojishan Formation (159―164 Ma) underlies the Daohugou deposits, rather than overlying the latter as previously proposed. Thus, the age of the Daohugou deposits should be younger than the age of the ignimbrite, and thus it was incorrect to correlate the Daohugou Bed with the Middle Jurassic Jiulongshan Formation. Although biostratigraphic studies based on conchostracans and insects support a Middle Jurassic-early Late Jurassic age for the Daohugou deposits, vertebrate fossils such as Liaoxitriton, Jeholopterus and feathered maniraptorans show much resemblance to those of the Yixian Formation. In other words, despite the absence of Lycoptera, a typical fish of the Jehol Biota, the Daohugou vertebrate assemblage is closer to that of the Early Cretaceous Jehol Biota than to any other biota. We propose that the Daohugou fossil assemblage probably represents the earliest evolutionary stage of the Jehol Biota based on both vertebrate biostratigraphy and the sedimentological and volcanic features which suggest the Daohugou deposit belongs to the same cycle of volcanism and sedimentation as the Yixian Formation of the Jehol Group.

  9. Modes of fossil preservation

    Science.gov (United States)

    Schopf, J.M.

    1975-01-01

    The processes of geologic preservation are important for understanding the organisms represented by fossils. Some fossil differences are due to basic differences in organization of animals and plants, but the interpretation of fossils has also tended to be influenced by modes of preservation. Four modes of preservation generally can be distinguished: (1) Cellular permineralization ("petrifaction") preserves anatomical detail, and, occasionally, even cytologic structures. (2) Coalified compression, best illustrated by structures from coal but characteristic of many plant fossils in shale, preserves anatomical details in distorted form and produces surface replicas (impressions) on enclosing matrix. (3) Authigenic preservation replicates surface form or outline (molds and casts) prior to distortion by compression and, depending on cementation and timing, may intergrade with fossils that have been subject to compression. (4) Duripartic (hard part) preservation is characteristic of fossil skeletal remains, predominantly animal. Molds, pseudomorphs, or casts may form as bulk replacements following dissolution of the original fossil material, usually by leaching. Classification of the kinds of preservation in fossils will aid in identifying the processes responsible for modifying the fossil remains of both animals and plants. ?? 1975.

  10. Abstracts: Eighth Annual Conference on Fossil Energy Materials. Fossil Energy Program

    Energy Technology Data Exchange (ETDEWEB)

    1994-07-01

    Abstracts are presented for about 40 papers. The Fossil Energy Advanced Research and Technology Development Materials program is an integrated materials research activity of the fossil energy coal program, whose objective is to conduct R and D for all advanced coal conversion and utilization technologies. The program is aimed at understanding materials behavior in coal system environments and the development of new materials for improving plant operations and reliability. A generic approach is used for addressing multiple coal technologies; for example, the hot-gas particulate filter development is applicable to pressurized fluidized bed combustion, integrated coal gasification combined-cycle, coal combustion, and indirectly fired combined-cycle systems.

  11. Comparative evaluation of solar, fission, fusion, and fossil energy resources. Part 4: Energy from fossil fuels

    Science.gov (United States)

    Williams, J. R.

    1974-01-01

    The conversion of fossil-fired power plants now burning oil or gas to burn coal is discussed along with the relaxation of air quality standards and the development of coal gasification processes to insure a continued supply of gas from coal. The location of oil fields, refining areas, natural gas fields, and pipelines in the U.S. is shown. The technologies of modern fossil-fired boilers and gas turbines are defined along with the new technologies of fluid-bed boilers and MHD generators.

  12. The palynological record of the Eemian interglacial and Early Vistulian glaciation in deposits of the Żabieniec Południowy fossil basin (Łódź Plateau, central Poland, and its palaeogeographic significance

    Directory of Open Access Journals (Sweden)

    Majecka Aleksandra

    2014-12-01

    Full Text Available The vegetation of the Eemian interglacial and Early Vistulian glaciation was reconstructed on the basis of pollen analysis, biogenic and mineral-biogenic sediments from the Żabieniec Południowy locality. It was revealed that the present-day fossil reservoir was formerly a lake existing continuously from the decline of the Warta stadial (LG MPG to the end of the Early Vistulian (EV4. The upper Plenivistulian age of top sediments, previously accepted on the basis of the radiocarbon date 24 200 ± 350 yrs BP (uncalibrated, was not confirmed by pollen analysis. In the pollen record from the nearby Żabieniec mire a break in biogenic accumulation corresponding to the Lower and Middle Plenivistulian was discovered. In view of the character of Plenivistulian morphogenesis in that area it appears that the deposits of both basins illustrate the development of one large melt-out depression during the whole postglacial period.

  13. Fossil proboscidea and edentata of the San Pedro Valley, Arizona

    Science.gov (United States)

    Gidley, James Williams

    1926-01-01

    A preliminary report on the fossil vertebrates of the San Pedro Valley, Ariz., collected by Kirk Bryan and me in the winter of 1920 and 1921 was published in 1922. This report includes a brief statement regarding the geology of the locality and a preliminary list of fossil vertebrates obtained by the expedition of 1921, with descriptions of the rodents and rabbits. Two additional papers on this interesting fauna have also appeared, one on the turtles by C.W. Gilmore and one on the birds by Alexander Wetmore. The present contribution deals with the proboscideans and edentates and gives a somewhat fuller discussion of the geology of the fossil-bearing beds.

  14. Fossil-energy program. Progress report for June 1981

    Energy Technology Data Exchange (ETDEWEB)

    1981-08-01

    This report - the eighty-third of series - is a compendium of monthly progress reports for the ORNL research and development programs that are in support of the increased utilization of coal and other fossil fuel alternatives as sources of clean energy. The projects reported this month include those for coal conversion development, chemical research and development, materials technology, component development and process evaluation, technical support to major liquefaction projects, process analysis and engineering evaluations, fossil energy environmental analysis, flue gas desulfurization, coal preparation waste utilization, atmospheric fluidized bed coal combustor for cogeneration, TVA FBC demonstration plant program technical support, PFBC systems analysis, fossil fuel applications assessments, performance assurance system support for fossil energy projects, international energy technology assessment, generalized equilibrium models for liquid and gaseous fuel supplies, analyses of coal production goals, and fossil energy information center.

  15. TryCYCLE: A Prospective Study of the Safety and Feasibility of Early In-Bed Cycling in Mechanically Ventilated Patients

    Science.gov (United States)

    Molloy, Alexander J.; Clarke, France J.; Ajami, Daana; McCaughan, Magda; Obrovac, Kristy; Murphy, Christina; Camposilvan, Laura; Herridge, Margaret S.; Koo, Karen K. Y.; Rudkowski, Jill; Seely, Andrew J. E.; Zanni, Jennifer M.; Mourtzakis, Marina; Piraino, Thomas; Cook, Deborah J.

    2016-01-01

    Introduction The objective of this study was to assess the safety and feasibility of in-bed cycling started within the first 4 days of mechanical ventilation (MV) to inform a future randomized clinical trial. Methods We conducted a 33-patient prospective cohort study in a 21-bed adult academic medical-surgical intensive care unit (ICU) in Hamilton, ON, Canada. We included adult patients (≥ 18 years) receiving MV who walked independently pre-ICU. Our intervention was 30 minutes of in-bed supine cycling 6 days/week in the ICU. Our primary outcome was Safety (termination), measured as events prompting cycling termination; secondary Safety (disconnection or dislodgement) outcomes included catheter/tube dislodgements. Feasibility was measured as consent rate and fidelity to intervention. For our primary outcome, we calculated the binary proportion and 95% confidence interval (CI). Results From 10/2013-8/2014, we obtained consent from 34 of 37 patients approached (91.9%), 33 of whom received in-bed cycling. Of those who cycled, 16(48.4%) were female, the mean (SD) age was 65.8(12.2) years, and APACHE II score was 24.3(6.7); 29(87.9%) had medical admitting diagnoses. Cycling termination was infrequent (2.0%, 95% CI: 0.8%-4.9%) and no device dislodgements occurred. Cycling began a median [IQR] of 3 [2, 4] days after ICU admission; patients received 5 [3, 8] cycling sessions with a median duration of 30.7 [21.6, 30.8] minutes per session. During 205 total cycling sessions, patients were receiving invasive MV (150 [73.1%]), vasopressors (6 [2.9%]), sedative or analgesic infusions (77 [37.6%]) and dialysis (4 [2.0%]). Conclusions Early cycling within the first 4 days of MV among hemodynamically stable patients is safe and feasible. Research to evaluate the effect of early cycling on patient function is warranted. Trial Registration Clinicaltrials.gov: NCT01885442 PMID:28030555

  16. A WELL PRESERVED SKELETON OF THE FOSSIL SHARK COSMOPOLITODUS HASTALIS FROM THE LATE MIOCENE OF PERU, FEATURING FISH REMAINS AS FOSSILIZED STOMACH CONTENTS

    Directory of Open Access Journals (Sweden)

    ALBERTO COLLARETA

    2017-01-01

    Full Text Available Both the preservation of the poorly mineralized skeleton of sharks and the preservation of stomach contents are rarely observed in the fossil record. Here we report on a partial skeleton of a lamniform shark, including portions of the visceral arches and the anterior segment of the vertebral column, collected from the late Miocene beds of the Pisco Formation exposed at Cerro Yesera (Ica Desert, South Peru. Based on the morphology of the preserved teeth, this specimen was determined as a juvenile of the extinct lamnid species Cosmopolitodus hastalis. The shark skeleton includes remains of fish (featuring a pilchard determined as Sardinops sp. cf. S. sagax in the abdominal region. These fish remains are interpreted herein as the fossilized stomach contents of the shark. For the first time, piscivory is demonstrated in a juvenile individual of Cosmopolitodus hastalis. This result is consistent with the current knowledge about the feeding habits of immature individuals of extant lamniform shark species (including Carcharodon carcharias and Isurus oxyrinchus. Our report further outlines the fundamental role of schooling pilchards in the late Miocene trophic chains of the highly productive coastal waters off present South Peru. Moreover, the find of this well preserved shark skeleton strengthens the qualification of the Pisco Formation as a Fossil-Lagerstätte, and emphasizes the role of early mineralization processes in cases of exceptional preservation.

  17. Fossil turbulence revisited

    CERN Document Server

    Gibson, C H

    1999-01-01

    A theory of fossil turbulence presented in the 11th Liege Colloquium on Marine turbulence is "revisited" in the 29th Liege Colloquium "Marine Turbulence Revisited". The Gibson (1980) theory applied universal similarity theories of turbulence and turbulent mixing to the vertical evolution of an isolated patch of turbulence in a stratified fluid as it is constrained and fossilized by buoyancy forces. Towed oceanic microstructure measurements of Schedvin (1979) confirmed the predicted universal constants. Universal constants, spectra, hydrodynamic phase diagrams (HPDs) and other predictions of the theory have been reconfirmed by a wide variety of field and laboratory observations. Fossil turbulence theory has many applications; for example, in marine biology, laboratory and field measurements suggest phytoplankton species with different swimming abilities adjust their growth strategies differently by pattern recognition of several days of turbulence-fossil-turbulence dissipation and persistence times above thres...

  18. A new archosauriform (Reptilia: Diapsida from the Manda beds (Middle Triassic of southwestern Tanzania.

    Directory of Open Access Journals (Sweden)

    Sterling J Nesbitt

    Full Text Available BACKGROUND: Archosauria and their closest relatives, the non-archosaurian archosauriforms, diversified in the Early and Middle Triassic, soon after the end-Permian extinction. This diversification is poorly documented in most Lower and Middle Triassic rock sequences because fossils of early groups of archosauriforms are relatively rare compared to those of other amniotes. The early Middle Triassic (? late Anisian Manda beds of southwestern Tanzania form an exception, with early archosaur skeletons being relatively common and preserved as articulated or associated specimens. The Manda archosaur assemblage is exceptionally diverse for the Middle Triassic. However, to date, no non-archosaurian archosauriforms have been reported from these rocks. METHODOLOGY/PRINCIPAL FINDINGS: Here, we name a new taxon, Asperoris mnyama gen. et sp. nov., from the Manda beds and thoroughly describe the only known specimen. The specimen consists of a well-preserved partial skull including tooth-bearing elements (premaxilla, maxilla, the nasal, partial skull roof, and several incomplete elements. All skull elements are covered in an autapomorphic highly rugose sculpturing. A unique combination of character states indicates that A. mnyama lies just outside Archosauria as a stem archosaur within Archosauriformes, but more precise relationships of A. mnyama relative to other early archosauriform clades (e.g., Erythrosuchidae cannot be determined currently. CONCLUSIONS/SIGNIFICANCE: Asperoris mnyama is the first confirmed non-archosaurian archosauriform from the Manda beds and increases the morphological and taxonomic diversity of early archosauriforms known from the Middle Triassic. The direct association of A. mnyama with species referable to Archosauria demonstrates that non-archosaurian archosauriforms were present during the rise and early diversification of Archosauria. Non-archosaurian archosauriforms and archosaurs co-occur in fossil reptile assemblages across

  19. Fossil worm burrows reveal very early terrestrial animal activity and shed light on trophic resources after the end-cretaceous mass extinction.

    Directory of Open Access Journals (Sweden)

    Karen Chin

    Full Text Available The widespread mass extinctions at the end of the Cretaceous caused world-wide disruption of ecosystems, and faunal responses to the one-two punch of severe environmental perturbation and ecosystem collapse are still unclear. Here we report the discovery of in situ terrestrial fossil burrows from just above the impact-defined Cretaceous-Paleogene (K/Pg boundary in southwestern North Dakota. The crisscrossing networks of horizontal burrows occur at the interface of a lignitic coal and silty sandstone, and reveal intense faunal activity within centimeters of the boundary clay. Estimated rates of sedimentation and coal formation suggest that the burrows were made less than ten thousand years after the end-Cretaceous impact. The burrow characteristics are most consistent with burrows of extant earthworms. Moreover, the burrowing and detritivorous habits of these annelids fit models that predict the trophic and sheltering lifestyles of terrestrial animals that survived the K/Pg extinction event. In turn, such detritus-eaters would have played a critical role in supporting secondary consumers. Thus, some of the carnivorous vertebrates that radiated after the K/Pg extinction may owe their evolutionary success to thriving populations of earthworms.

  20. Fossil Worm Burrows Reveal Very Early Terrestrial Animal Activity and Shed Light on Trophic Resources after the End-Cretaceous Mass Extinction

    Science.gov (United States)

    Chin, Karen; Pearson, Dean; Ekdale, A. A.

    2013-01-01

    The widespread mass extinctions at the end of the Cretaceous caused world-wide disruption of ecosystems, and faunal responses to the one-two punch of severe environmental perturbation and ecosystem collapse are still unclear. Here we report the discovery of in situ terrestrial fossil burrows from just above the impact-defined Cretaceous-Paleogene (K/Pg) boundary in southwestern North Dakota. The crisscrossing networks of horizontal burrows occur at the interface of a lignitic coal and silty sandstone, and reveal intense faunal activity within centimeters of the boundary clay. Estimated rates of sedimentation and coal formation suggest that the burrows were made less than ten thousand years after the end-Cretaceous impact. The burrow characteristics are most consistent with burrows of extant earthworms. Moreover, the burrowing and detritivorous habits of these annelids fit models that predict the trophic and sheltering lifestyles of terrestrial animals that survived the K/Pg extinction event. In turn, such detritus-eaters would have played a critical role in supporting secondary consumers. Thus, some of the carnivorous vertebrates that radiated after the K/Pg extinction may owe their evolutionary success to thriving populations of earthworms. PMID:23951041

  1. Discovering Fossils--A Hands-on Lab.

    Science.gov (United States)

    Goldstein, Alan

    2002-01-01

    Describes fossil investigations developed and provided by the Falls of the Ohio State Park near Louisville, Kentucky. The Devonian shale beds contain representatives of over 600 species including corals, sponges, brachiopods, mollusks, and echinoderms. Rather than focusing on identification, the activities emphasize the past ecological…

  2. Fossil Odobenidae in some Dutch collections (Mammalia, Carnivora)

    NARCIS (Netherlands)

    Bosscha Erdbrink, D.P.; Bree, van P.J.H.

    1986-01-01

    Eight cranial and five postcranial fossil specimens are described and identified as remains of Odobenidae. Two of these (one, from Rhenen, certainly, and the other tentatively) are ascribed to the fossil, Early Pleistocene Odobenus huxleyi (Lankester, 1865), the others to the recent form, O.

  3. First fossil chimpanzee.

    Science.gov (United States)

    McBrearty, Sally; Jablonski, Nina G

    2005-09-01

    There are thousands of fossils of hominins, but no fossil chimpanzee has yet been reported. The chimpanzee (Pan) is the closest living relative to humans. Chimpanzee populations today are confined to wooded West and central Africa, whereas most hominin fossil sites occur in the semi-arid East African Rift Valley. This situation has fuelled speculation regarding causes for the divergence of the human and chimpanzee lineages five to eight million years ago. Some investigators have invoked a shift from wooded to savannah vegetation in East Africa, driven by climate change, to explain the apparent separation between chimpanzee and human ancestral populations and the origin of the unique hominin locomotor adaptation, bipedalism. The Rift Valley itself functions as an obstacle to chimpanzee occupation in some scenarios. Here we report the first fossil chimpanzee. These fossils, from the Kapthurin Formation, Kenya, show that representatives of Pan were present in the East African Rift Valley during the Middle Pleistocene, where they were contemporary with an extinct species of Homo. Habitats suitable for both hominins and chimpanzees were clearly present there during this period, and the Rift Valley did not present an impenetrable barrier to chimpanzee occupation.

  4. Fossil energy biotechnology: A research needs assessment. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1993-11-01

    The Office of Program Analysis of the US Department of Energy commissioned this study to evaluate and prioritize research needs in fossil energy biotechnology. The objectives were to identify research initiatives in biotechnology that offer timely and strategic options for the more efficient and effective uses of the Nation`s fossil resource base, particularly the early identification of new and novel applications of biotechnology for the use or conversion of domestic fossil fuels. Fossil energy biotechnology consists of a number of diverse and distinct technologies, all related by the common denominator -- biocatalysis. The expert panel organized 14 technical subjects into three interrelated biotechnology programs: (1) upgrading the fuel value of fossil fuels; (2) bioconversion of fossil feedstocks and refined products to added value chemicals; and, (3) the development of environmental management strategies to minimize and mitigate the release of toxic and hazardous petrochemical wastes.

  5. Trace fossils and sedimentary facies from a Late Cambrian-Early Ordovician tide-dominated shelf (Santa Rosita Formation, northwest Argentina): Implications for ichnofacies models of shallow marine successions

    Science.gov (United States)

    Mangano, M.G.; Buatois, L.A.; Acenolaza, G.F.

    1996-01-01

    The Santa Rosita Formation is one the most widely distributed lower Paleozoic units of northwest Argentina. At the Quebrada del Salto Alto section, east of Purmamarca, Jujuy Province, it is represented by four sedimentary facies: thick-bedded planar cross-stratified quartzose sandstones (A), thin-bedded planar cross-stratified quartzose sandstones and mudstones (B), wave-rippled sandstones and bioturbated mudstones (C), and black and greenish gray shales (D). Paleocurrent data, sandstone architecture, and sedimentary structures from facies A and B indicate bipolar/bimodal paleoflows, suggesting the action of tidal currents. The succession is interpreted as that of a tide-dominated shelf, with only secondary influence of wave processes. Trace fossils are restricted to facies B and C. The Cruziana ichnocoenosis is preserved on the soles of thin-bedded planar cross-stratified quartzose sandstones (facies B). This ichnocoenosis consists of Conostichus isp., Cruziana omanica, C. semiplicata, C. cf. tortworthi, Cruziana isp. Helminthopsis abeli, Monomorphichnus bilinearis, M. multilineatus, Palaeophycus tubularis, Rusophycus carbonarius, R. latus, and R. isp. The occurrence of Cruziana semiplicata, C. omanica, C. cf. tortworthi, and Rusophycus latus supports a Late Cambrian-Tremadoc age. Slabbing of Cruziana shows complex interactions between biologic and sedimentologic processes, and suggests a predominance of exhumed traces, washed out and recast by tractive sand deposition. Sandstone soles are densely packed with biogenic structures and exhibit distinctive clusters of Rusophycus isp. that most likely represent trilobite nesting burrows. The Cruziana ichnocoenosis records the resident fauna of a protected, lower intertidal to subtidal interbar setting. The Skolithos ichnocoenosis is represented by high to low density vertical burrows of Skolithos linearis, which extend downwards to the quartzose sandstone soles of facies B and cross the Cruziana ichnocoenosis. The

  6. The taphonomy of a remarkable leaf bed assemblage from the Late Oligocene-Early Miocene Gore Lignite Measures, southern New Zealand

    Energy Technology Data Exchange (ETDEWEB)

    Ferguson, David K.; Zetter, Reinhard; Vavra, Norbert [Department of Paleontology, University of Vienna, Althanstrasse 14, A-1090 Vienna (Austria); Lee, Daphne E. [Department of Geology, University of Otago, PO Box 56, Dunedin (New Zealand); Bannister, Jennifer M. [Department of Botany, University of Otago, PO Box 56, Dunedin (New Zealand); Jordan, Gregory J. [School of Plant Sciences, University of Tasmania, Private Bag 55, Hobart, Tasmania 7001 (Australia); Mildenhall, Dallas C. [GNS Science, PO Box 30-368, Lower Hutt (New Zealand)

    2010-08-01

    A diverse assemblage of fossil leaves showing cellular detail is reported from the Late Oligocene-Early Miocene Gore Lignite Measures, southern New Zealand. The leaf-remains include at least five conifers, such as the genera Agathis, Dacrycarpus, Phyllocladus and Dacrydium, as well as a number of angiosperms including Gymnostoma, Nothofagus Subgenus Brassospora, Phormium, Proteaceae, Sapindaceae and Ericaceae. A parallel palynological study has identified a number of the same elements. The leaf layers represent litter horizons laid down in pools on the surface of a subtropical ombrotrophic forest mire that formed on an extensive low-lying coastal plain. Highly acidic water ponded in tree-fall depressions prevented microbial decay of the foliage. Taxa represented by both leaves and pollen are considered to have been components of the autochthonous swamp forest. Some other pollen grains are thought to represent local elements, based on the pollination biology of their nearest living relatives. Other taxa whose extant representatives are wind-pollinated may have grown further away. (author)

  7. Central heating: fossil-fired boilers

    Energy Technology Data Exchange (ETDEWEB)

    Blazek, C.F.; Baker, N.R.; Tison, R.R.

    1979-05-01

    This evaluation provides performance and cost data for fossil-fuel-fired steam boilers, hot-water generators, and thermal fluid generators currently available from manufacturers. Advanced-technology fluidized-bed boilers also are covered. Performance characteristics investigated include unit efficiencies, turndown capacity, and pollution requirements. Costs are tabulated for equipment and installation of both field-erected and packaged units. The information compiled in this evaluation will assist in the process of selecting energy-conversion units required for industrial, commercial, and residential applications.

  8. First Record of Fossil Mesocupes from China (Coleoptera: Archostemata: Cupedidae)

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Three new fossil species of the genus Mesocupes of fossil cupedids, M. angustilabialis sp.nov., M. latilabialis sp. nov. and M. collaris sp. nov., are described from the Jiulongshan Formation of Inner Mongolia, China. These new species are the first three records of fossil Mesocupes in China as well as the oldest ones in the world now. This finding also extends the geographical distribution of this genus from Central to East Asia. In addition, based on the ratio of the length of the last to the penultimate abdominal ventrites of new beetles distinctly lower than that of the species from the Karabastau Formation, the age of Daohugou fossil-bearing beds might be older than that of Karatau assemblage and consequently of Middle Jurassic.

  9. Mineralization of fossil wood

    NARCIS (Netherlands)

    Buurman, P.

    1972-01-01

    Several pieces of fossil wood have been analyzed with X-ray diffraction and were grouped on the basis of mineralogical composition. Various mineralizations were studied in thin sections and by means of the scanning electron microscope. Wood-opals appear to show a structure preservation that points t

  10. Fossils and decapod phylogeny

    NARCIS (Netherlands)

    Schram, Frederick R.; Dixon, Christopher

    2003-01-01

    An expanded series of morphological characters developed for a cladistic analysis of extant decapods has yielded a new hypothesis for the phylogeny of the group. Application of this database to selected fossil genera produces some interesting results and demonstrates the feasibility of treating foss

  11. Fossil Dot Com

    DEFF Research Database (Denmark)

    2011-01-01

    , and the transformation has moved 50% of us to live in cities, whereas a mere 3% dwelled in cities in 1800. However, this 200 year long fossil fuelled bubble is coming to an end, which affects societies around the world and the way we design products and services for these societies beyond imagination. With rich...

  12. Fossil energy research meeting

    Energy Technology Data Exchange (ETDEWEB)

    Kropschot, R. H.; Phillips, G. C.

    1977-12-01

    U.S. ERDA's research programs in fossil energy are reviewed with brief descriptions, budgets, etc. Of general interest are discussions related to the capabilities for such research of national laboratories, universities, energy centers, etc. Of necessity many items are treated briefly, but a general overview of the whole program is provided. (LTN)

  13. Two episodic changes of trace fossils through the Permian-Triassic transition in the Meishan cores,Zhejiang Province

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Six ichnogenera,Chondrites,Palaeophycus,Planolites,Rhizocorallium,Skolithos,and Thalassinoides,were identified from the drilling cores near the Global Stratotype Section and Point(GSSP) of Permian-Triassic boundary at Meishan,Zhejiang Province.The ichnological indices,including abundance,bioturbation index,and disturbed depth of trace fossils,show two episodes of intense changes near the Permian-Triassic Boundary(PTB).Episode I occurred in Beds 25-27b when the ecologically complicate forms such as Chondrites,Skolithos,Rhizocorallium,and Thalassinoides disappeared hereafter,the bioturbation index reduced from 1-5 to 1-3,and the disturbed depth declined from 5-66 to 2-5 cm.Episode II took place at the base of Bed 33 with the disappearance of Palaeophycus and Planolites,and subsequent absence of trace fossils and bioturbation till the middle-upper part of Bed 41 when the disturbed structures reoccurred,but they are only tiny Planolites and the bioturbation index was never higher than 3 and the disturbed depth less than 4 mm.Episode I shows an intense change,corresponding to the main stage of the end-Permian mass extinction,whereas Episode II is relatively weak,corresponding to the epilogue of the mass extinction of trace makers in the Early Triassic.Subsequently,ichnofossils were dominated by surface tracks in simple ecological habit and structures.This phenomenon indicates that the Early Triassic benthonic fauna is changed from sessile benthic system to mobile benthic system after the end-Permian mass extinction.In other words,the evolution of the trace fossils across the Permian-Triassic transition had an episodic process similar to the body fossils.In addition,the change of ichnofabrics is well coincided with the negative excursion of carbon isotopes and the expansion of cyanobacteria.As the results of physical and biogenic processes,trace fossils provided unique materials for the study of the biotic and environmental events,as well as their coupling evolution

  14. Lost toy? Monsters under the bed? Contributions of temperament and family factors to early internalizing problems in boys and girls.

    Science.gov (United States)

    Marakovitz, Susan E; Wagmiller, Robert L; Mian, Nicholas D; Briggs-Gowan, Margaret J; Carter, Alice S

    2011-01-01

    This study was designed to examine the contribution of multiple risk factors to early internalizing problems and to investigate whether family and ecological context moderated the association between child temperament and internalizing outcomes. A sample of 1,202 mothers of 2- and 3-year-old children completed a survey of child social-emotional functioning, family environment, and violence exposure. Child temperament, maternal affective symptoms, and family expressiveness were associated with child anxiety and depression problems. Violence exposure was related only to child anxiety. When maternal affective symptoms were elevated, inhibited girls but not boys were rated as more anxious and youngsters with heightened negative emotionality were rated as more depressed. Family expressiveness moderated the association between inhibited temperament and anxiety symptoms.

  15. Fossil Association from the Lower Cambrian Yanjiahe Formation in the Yangtze Gorges Area, Hubei, South China

    Institute of Scientific and Technical Information of China (English)

    GUO Junfeng; Tsuyoshi KOMIYA; LI Yong; HAN Jian; ZHANG Xingliang; ZHANG Zhifei; OU Qiang; LIU Jianni; SHU Degan; Shigenori MARUYAMA

    2008-01-01

    Apart from previously reported Small Shelly Fossils (SSFs), a macroscopic fossil assemblage, comprising abundant algae, cone-shaped tubular fossil forms, and probable impressions of a megascopic metazoan, comes from the Lower Cambrian Yanjiahe Formation in the Yangtze Gorges area of western Hubei Province, south China. The visible fossils are preserved in thin-laminated siltstone or muddy siltstone intercalated between 8-15 mm-thick carbonate deposits, probably representing sedimentary settings of a constrained local depression in the shallow water carbonate platform during the Early Cambrian Meishucunian Stage. The macroscopic fossil association provides significant fossil evidence about the evolution of life from the late Precambrian to the 'Cambrian explosion' interval.

  16. Sustainability of Fossil Fuels

    Science.gov (United States)

    Lackner, K. S.

    2002-05-01

    For a sustainable world economy, energy is a bottleneck. Energy is at the basis of a modern, technological society, but unlike materials it cannot be recycled. Energy or more precisely "negentropy" (the opposite of entropy) is always consumed. Thus, one either accepts the use of large but finite resources or must stay within the limits imposed by dilute but self-renewing resources like sunlight. The challenge of sustainable energy is exacerbated by likely growth in world energy demand due to increased population and increased wealth. Most of the world still has to undergo the transition to a wealthy, stable society with the near zero population growth that characterizes a modern industrial society. This represents a huge unmet demand. If ten billion people were to consume energy like North Americans do today, world energy demand would be ten times higher. In addition, technological advances while often improving energy efficiency tend to raise energy demand by offering more opportunity for consumption. Energy consumption still increases at close to the 2.3% per year that would lead to a tenfold increase over the course of the next century. Meeting future energy demands while phasing out fossil fuels appears extremely difficult. Instead, the world needs sustainable or nearly sustainable fossil fuels. I propose the following definition of sustainable under which fossil fuels would well qualify: The use of a technology or resource is sustainable if the intended and unintended consequences will not force its abandonment within a reasonable planning horizon. Of course sustainable technologies must not be limited by resource depletion but this is only one of many concerns. Environmental impacts, excessive land use, and other constraints can equally limit the use of a technology and thus render it unsustainable. In the foreseeable future, fossil fuels are not limited by resource depletion. However, environmental concerns based on climate change and other environmental

  17. Fossil gastropods from the Indian Upper Siwaliks and their stable carbon and oxygen isotope values indicate presence of cold climatic conditions in the Early Pleistocene.

    Science.gov (United States)

    Singh Kotla, Simran

    2016-04-01

    The Early Pleistocene in general is characterized by widespread glaciations in the Northern Hemisphere. Early to Middle Pleistocene freshwater Pinjor Formation (Upper Siwalik) exposed all along the Himalayan Foothills preserves a diverse faunal and floral assemblage. We carried out paleontological (gastropods) and stable isotope (carbon and oxygen isotope) studies of a 6 m thick swamp/pond deposit (that represents ~ 12,000 yrs) of Pinjor Formation, exposed near the Village Nadah, Panchkula (Haryana) and dated to ~ 1.8 Ma (Azzaroli and Napoleon,1982). We have identified four gastropod species in the assemblage, Lymnae sp., Gyraulus sp., Viviparous bengalensis and Hippeutis complantus. The first two are widespread throughout the globe. Lymnae can exist in temperature range of 19 to 24 ° C and occur in Palearctic and Neoartic regions (animalbase.org). Gyraulus occur in Holoarctic region with temperature ranging from 17.8 to 30 ° C (animalbase.org, theaquariumwiki.com), whereas Viviparous bengalensis typically exists in the Oriental region suggesting an overall warm and humid condition (Moore,1997). Hippeutis complantus on the other hand exists in palearctic regions upto 63 ° N (Aplinarska and Cisewka 2006) under cold (6 ° to 23.3 ° C) and dry climatic conditions (Spyra., 2014).The powdered gastropod shell samples were analyzed using Continues Flow Isotope Ratio Mass Spectrometer (CF-IRMS) at the Wadia Institute of Himalayan Geology, Dehradun, India. The δ13C values of gastropod shells fall between -2.56‰ and 6.14‰ VPDB and suggest the dominance of C4 vegetation. The δ18O value of gastropod shell fall between -0.64‰ and -7.80‰ VPDB, suggesting fluctuation of climate between warm and cold conditions . Presence of Hippeutis complantus may suggest the extension of palearctic region up to Panchkula (Haryana, India) in the Early Pleistocene which presently lies in the Oriental Province. Therefore, our results indicate that the overall climatic condition

  18. The Review of Interlanguage Fossilization

    Institute of Scientific and Technical Information of China (English)

    李霄露

    2011-01-01

    Interlanguage fossilization is a common phenomenon in second language acquisition. This paper reyiews the important achievements in the study of interlanguage fossilization, analyzing its definition, types and causes. And then find some ways to re- duce the interference of interlanguage fossilization in second language learning.

  19. Exceptional fossil preservation and the cambrian explosion.

    Science.gov (United States)

    Butterfield, Nicholas J

    2003-02-01

    Exceptionally preserved, non-biomineralizing fossils contribute importantly to resolving details of the Cambrian explosion, but little to its overall patterns. Six distinct "types" of exceptional preservation are identified for the terminal Proterozoic-Cambrian interval, each of which is dependent on particular taphonomic circumstances, typically restricted both in space and time. Taphonomic pathways yielding exceptional preservation were particularly variable through the Proterozoic-Cambrian transition, at least in part a consequence of contemporaneous evolutionary innovations. Combined with the reasonably continuous record of "Doushantuo-type preservation," and the fundamentally more robust records of shelly fossils, phytoplankton cysts and trace fossils, these taphonomic perturbations contribute to the documentation of major evolutionary and biogeochemical shifts through the terminal Proterozoic and early Cambrian.Appreciation of the relationship between taphonomic pathway and fossil expression serves as a useful tool for interpreting exceptionally preserved, often problematic, early Cambrian fossils. In shale facies, for example, flattened non-biomineralizing structures typically represent the remains of degradation-resistant acellular and extracellular "tissues" such as chaetae and cuticles, whereas three-dimensional preservation represents labile cellular tissues with a propensity for attracting and precipitating early diagenetic minerals. Such distinction helps to identify the acuticular integument of hyolithids, the chaetae-like nature of Wiwaxia sclerites, the chaetognath-like integument of Amiskwia, the midgut glands of various Burgess Shale arthropods, and the misidentification of deposit-feeding arthropods in the Chengjiang biota. By the same reasoning, putative lobopods in the Sirius Passet biota and putative deuterostomes in the Chengiang biota are better interpreted as arthropods.

  20. Fossilization Processes in Thermal Springs

    Science.gov (United States)

    Farmer, Jack D.; Cady, Sherry; Desmarais, David J.; Chang, Sherwood (Technical Monitor)

    1995-01-01

    To create a comparative framework for the study of ancient examples, we have been carrying out parallel studies of the microbial biosedimentology, taphonomy and geochemistry of modem and sub-Recent thermal spring deposits. One goal of the research is the development of integrated litho- and taphofacies models for siliceous and travertline sinters. Thermal springs are regarded as important environments for the origin and early evolution of life on Earth, and we seek to utilize information from the fossil record to reconstruct the evolution of high temperature ecosystems. Microbial contributions to the fabric of thermal spring sinters occur when population growth rates keep pace with, or exceed rates of inorganic precipitation, allowing for the development of continuous biofilms or mats. In siliceous thermal springs, microorganisms are typically entombed while viable. Modes of preservation reflect the balance between rates of organic matter degradation, silica precipitation and secondary infilling. Subaerial sinters are initially quite porous and permeable and at temperatures higher than about 20 C, organic materials are usually degraded prior to secondary infilling of sinter frameworks. Thus, organically-preserved microfossils are rare and fossil information consists of characteristic biofabrics formed by the encrustation and underplating of microbial mat surfaces. This probably accounts for the typically low total organic carbon values observed in thermal spring deposits. In mid-temperature, (approx. 35 - 59 C) ponds and outflows, the surface morphology of tufted Phormidium mats is preserved through mat underplating by thin siliceous: crusts. Microbial taxes lead to clumping of ceils and/or preferred filament orientations that together define higher order composite fabrics in thermal spring stromatolites (e.g. network, coniform, and palisade). At lower temperatures (less than 35 C), Calothrix mats cover shallow terracette pools forming flat carpets or pustular

  1. The largest fossil rodent

    Science.gov (United States)

    Rinderknecht, Andrés; Blanco, R. Ernesto

    2008-01-01

    The discovery of an exceptionally well-preserved skull permits the description of the new South American fossil species of the rodent, Josephoartigasia monesi sp. nov. (family: Dinomyidae; Rodentia: Hystricognathi: Caviomorpha). This species with estimated body mass of nearly 1000 kg is the largest yet recorded. The skull sheds new light on the anatomy of the extinct giant rodents of the Dinomyidae, which are known mostly from isolated teeth and incomplete mandible remains. The fossil derives from San José Formation, Uruguay, usually assigned to the Pliocene–Pleistocene (4–2 Myr ago), and the proposed palaeoenvironment where this rodent lived was characterized as an estuarine or deltaic system with forest communities. PMID:18198140

  2. Late Olenekian Radiolarians from Bedded Chert of Ashio Terrane, Northeast Japan,and Faunal Turnovers in Western Panthalassa during Early Triassic

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Late Olenekian assemblages in the western Panthalassa have been recovered from bedded radiolarian chert sequences of an accretionary complex, the Ashio belt. These faunas are documented and considered in terms of radiolarian diversity and faunal turnover during the latest Permian to Middle Triassic time. The fauna includes 30 radiolarians belonging to Spumellaria or Entactinaria, with two relicts from the Late Permian. This late Olenekian fauna is markedly different from Permian and Anisian faunas, respectively, and is herein named the Minowa fauna. Study of the literature indicates that radiolarian provinces were significantly disconnected between the western Panthalassa and eastern Tethys during late Olenekian time. Furthermore, 121 of 143 species disappeared during late Olenekian time, and in turn 118 new species appeared in the western Panthalassa around the Olenekian-Anisian boundary. It is concluded that faunal turnover occurred at least three times between the latest Permian and Middle Triassic. The first turnover is the Paleozoic-type radiolarian extinction at the Permian-Triassic boundary, the second is the diversification of spheroidal Spumellaria and Entactinaria between early and late Olenekian time, and the third is a faunal turnover from the Minowa fauna to the true Mesozoic-type radiolarian faunas that are characterized by multi-segmented Nassellaria.

  3. Chronic early life stress induced by limited bedding and nesting (LBN) material in rodents: critical considerations of methodology, outcomes and translational potential.

    Science.gov (United States)

    Walker, Claire-Dominique; Bath, Kevin G; Joels, Marian; Korosi, Aniko; Larauche, Muriel; Lucassen, Paul J; Morris, Margaret J; Raineki, Charlis; Roth, Tania L; Sullivan, Regina M; Taché, Yvette; Baram, Tallie Z

    2017-07-12

    The immediate and long-term effects of exposure to early life stress (ELS) have been documented in humans and animal models. Even relatively brief periods of stress during the first 10 days of life in rodents can impact later behavioral regulation and the vulnerability to develop adult pathologies, in particular an impairment of cognitive functions and neurogenesis, but also modified social, emotional, and conditioned fear responses. The development of preclinical models of ELS exposure allows the examination of mechanisms and testing of therapeutic approaches that are not possible in humans. Here, we describe limited bedding and nesting (LBN) procedures, with models that produce altered maternal behavior ranging from fragmentation of care to maltreatment of infants. The purpose of this paper is to discuss important issues related to the implementation of this chronic ELS procedure and to describe some of the most prominent endpoints and consequences, focusing on areas of convergence between laboratories. Effects on the hypothalamic-pituitary adrenal (HPA) axis, gut axis and metabolism are presented in addition to changes in cognitive and emotional functions. Interestingly, recent data have suggested a strong sex difference in some of the reported consequences of the LBN paradigm, with females being more resilient in general than males. As both the chronic and intermittent variants of the LBN procedure have profound consequences on the offspring with minimal external intervention from the investigator, this model is advantageous ecologically and has a large translational potential. In addition to the direct effect of ELS on neurodevelopmental outcomes, exposure to adverse early environments can also have intergenerational impacts on mental health and function in subsequent generation offspring. Thus, advancing our understanding of the effect of ELS on brain and behavioral development is of critical concern for the health and wellbeing of both the current

  4. Florissant Fossil Beds National Monument Tract and Boundary Data

    Data.gov (United States)

    National Park Service, Department of the Interior — These ESRI shape files are of National Park Service tract and boundary data that was created by the Land Resources Division. Tracts are numbered and created by the...

  5. Hagerman Fossil Beds National Monument Tract and Boundary Data

    Data.gov (United States)

    National Park Service, Department of the Interior — These ESRI shape files are of National Park Service tract and boundary data that was created by the Land Resources Division. Tracts are numbered and created by the...

  6. Agate Fossil Beds National Monument Tract and Boundary Data

    Data.gov (United States)

    National Park Service, Department of the Interior — These ESRI shape files are of National Park Service tract and boundary data that was created by the Land Resources Division. Tracts are numbered and created by the...

  7. Cycles in fossil diversity

    Energy Technology Data Exchange (ETDEWEB)

    Rohde, Robert A.; Muller, Richard A.

    2004-10-20

    It is well-known that the diversity of life appears to fluctuate during the course the Phanerozoic, the eon during which hard shells and skeletons left abundant fossils (0-542 Ma). Using Sepkoski's compendium of the first and last stratigraphic appearances of 36380 marine genera, we report a strong 62 {+-} 3 Myr cycle, which is particularly strong in the shorter-lived genera. The five great extinctions enumerated by Raup and Sepkoski may be an aspect of this cycle. Because of the high statistical significance, we also consider contributing environmental factors and possible causes.

  8. Biodesulfurization of fossil fuels.

    Science.gov (United States)

    Gray, Kevin A; Mrachko, Gregory T; Squires, Charles H

    2003-06-01

    Biotechnological techniques enabling the specific removal of sulfur from fossil fuels have been developed. In the past three years there have been important advances in the elucidation of the mechanisms of biodesulfurization; some of the most significant relate to the role of a flavin reductase, DszD, in the enzymology of desulfurization, and to the use of new tools that enable enzyme enhancement via DNA manipulation to influence both the rate and the substrate range of Dsz. Also, a clearer understanding of the unique desulfinase step in the pathway has begun to emerge.

  9. Trace fossil evidence for late Permian shallow water condition in Guryul ravine, Kashmir, India

    Science.gov (United States)

    Parcha, Suraj; Horacek, Micha; Krystyn, Leopold; Pandey, Shivani

    2015-04-01

    The present study is focused on the Late Permian (Changhsingian) succession, present in the Guryul ravine, Kashmir Basin. The basin has a complete Cambro-Triassic sequence and thus contains a unique position in the geology of Himalaya. The Guryul Ravine Permian mainly comprises of mixed siliciclastic-carbonate sediments deposited in a shallow-shelf or ramp setting. The present assemblage of Ichnofossils is the first significant report of trace fossils in the Guryul ravine since early reports in the 1970s. The Ichnofossils reported from this section include: Diplichnites, Dimorphichnus, Monomorphichnus, Planolites, Skolithos along with burrow, scratch marks and annelid worm traces?. The ichnofossils are mainly preserved in medium grain sandstone-mudstone facies. The Ichnofossils are widely distributed throughout the section and are mostly belonging to arthropods and annelid origin, showing behavioral activity, mainly dwelling and feeding, and evidence the dominant presence of deposit feeders. The vertical to slightly inclined biogenic structures are commonly recognized from semi-consolidated substrate which are characteristic features of the near shore/foreshore marine environment, with moderate to high energy conditions. The topmost layer of silty shale contains trace fossils like Skolithos and poorly preserved burrows. The burrow material filled is same as that of host rock. The studied Zewan C and D sequence represents the early to late part of the Changhsingian stage, from 40 to 5 m below the top of Zewan D member with bioturbation still evident in some limestone layers till 2 metres above. No trace fossils could be recognized in the topmost 3 m beds of Zewan D due to their gliding related amalgamated structure. The widespread distribution of traces and their in situ nature will be useful for interpretation of the paleoecological and paleoenvironmental conditions during the late Permian in the Guryul ravine of Kashmir.

  10. Fossil Energy Program progress report for May 1979

    Energy Technology Data Exchange (ETDEWEB)

    1979-07-01

    This report - the fifty eighth of a series - is a compendium of monthly progress reports for the ORNL research and development programs that are in support of the increased utilization of coal and other fossil fuel alternatives to oil and gas as sources of clean energy. The projects reported this month include those for coal conversion development, materials engineering, a coal equipment test program, an atmospheric fluid bed combustor for cogeneration, engineering studies and technical support, process and program analysis, environmental assessment studies, magnetic beneficiation of dry pulverized coal, technical support to the TVA fluid bed combustion program, coal cogeneration/district heating plant assessment, and chemical research and development.

  11. Bed bugs in healthcare settings.

    Science.gov (United States)

    Munoz-Price, L Silvia; Safdar, Nasia; Beier, John C; Doggett, Stephen L

    2012-11-01

    Infestations caused by bed bugs have resurfaced during the past decade across all continents. Even though bed bugs primarily cause skin manifestations in humans, a major stigma is placed upon people or institutions found to carry them. It is important for healthcare facilities to be prepared for this pest by implementing policies, carefully selecting materials used for hospital furniture, and educating providers on early identification and control.

  12. Paleomagnetism of Late Jurassic to Early Cretaceous red beds from the Cardamom Mountains, southwestern Cambodia: Tectonic deformation of the Indochina Peninsula

    Science.gov (United States)

    Tsuchiyama, Yukiho; Zaman, Haider; Sotham, Sieng; Samuth, Yos; Sato, Eiichi; Ahn, Hyeon-Seon; Uno, Koji; Tsumura, Kosuke; Miki, Masako; Otofuji, Yo-ichiro

    2016-01-01

    Late Jurassic to Early Cretaceous red beds of the Phuquoc Formation were sampled at 33 sites from the Sihanoukville and Koah Kong areas of the Phuquoc-Kampot Som Basin, southwestern Cambodia. Two high-temperature remanent components with unblocking temperature ranging 650°-670 °C and 670-690 °C were identified. The magnetization direction for the former component (D = 5.2 °, I = 18.5 ° with α95 = 3.1 ° in situ) reveals a negative fold test that indicates a post-folding secondary nature. However, the latter component, carried by specular hematite, is recognized as a primary remanent magnetization. A tilt-corrected mean direction of D = 43.4 °, I = 31.9 ° (α95 = 3.6 °) was calculated for the primary component at 11 sites, corresponding to a paleopole of 47.7°N, 178.9°E (A95 = 3.6 °). When compared with the 130 Ma East Asian pole, a southward displacement of 6.0 ° ± 3.5 ° and a clockwise rotation of 33.1 ° ± 4.0 ° of the Phuquoc-Kampot Som Basin (as a part of the Indochina Block) with respect to East Asia were estimated. This estimate of the clockwise rotation is ∼15° larger than that of the Khorat Basin, which we attribute to dextral motion along the Wang Chao Fault since the mid-Oligocene. The comparison of the herein estimated clockwise rotation with the counter-clockwise rotation reported from the Da Lat area in Vietnam suggests the occurrence of a differential tectonic rotation in the southern tip of the Indochina Block. During the southward displacement of the Indochina Block, the non-rigid lithosphere under its southern tip moved heterogeneously, while the rigid lithosphere under the Khorat Basin moved homogeneously.

  13. Fossil energy program. Progress report for May 1980

    Energy Technology Data Exchange (ETDEWEB)

    McNeese, L.E.

    1980-08-01

    This report - the seventieth of a series - is a compendium of monthly progress reports for the ORNL research and development programs that are in support of the increased utilization of coal and other fossil fuel alternatives to oil and gas as sources of clean energy. The projects reported this month include those for coal conversion development, chemical research and development, materials technology, component and process evaluation studies, technical support to major liquefaction projects, process analysis and engineering evaluations, fossil energy environmental analysis, coal preparation and waste utilization, coal preparation plant automation, technical support to the TVA fluidized bed combustion demonstration plant program, coal cogeneration/district heating plant assessment, atmospheric fluidized bed coal combustor for cogeneration, performance assurance system support and international energy technology assessment.

  14. Fossil Energy Program. Progress report for April 1980

    Energy Technology Data Exchange (ETDEWEB)

    McNeese, L.E.

    1980-06-01

    This report - the sixty-ninth of a series - is a compendium of monthly progress reports for the ORNL research and development programs that are in support of the increased utilization of coal and other fossil fuel alternatives to oil and gas as sources of clean energy. The projects reported this month include those for coal conversion development, chemical research and development, materials technology, component and process evaluation studies, technical support to major liquefaction projects, process analysis and engineering evaluations, fossil energy environmental analysis, coal preparation and waste utilization, coal preparation plant automation, atmospheric fluidized bed coal combustor for cogeneration, technical support to the TVA fluidized bed combustion demonstration plant program, coal cogeneration/district heating plant assessment, performance assurance system support, and international energy technology assessment.

  15. A Galactic Fossil

    Science.gov (United States)

    2007-05-01

    How old are the oldest stars? Using ESO's VLT, astronomers recently measured the age of a star located in our Galaxy. The star, a real fossil, is found to be 13.2 billion years old, not very far from the 13.7 billion years age of the Universe. The star, HE 1523-0901, was clearly born at the dawn of time. "Surprisingly, it is very hard to pin down the age of a star", the lead author of the paper reporting the results, Anna Frebel, explains. "This requires measuring very precisely the abundance of the radioactive elements thorium or uranium, a feat only the largest telescopes such as ESO's VLT can achieve." ESO PR Photo 23a/07 ESO PR Photo 23a/07 The 'Cosmic Clock' This technique is analogous to the carbon-14 dating method that has been so successful in archaeology over time spans of up to a few tens of thousands of years. In astronomy, however, this technique must obviously be applied to vastly longer timescales. For the method to work well, the right choice of radioactive isotope is critical. Unlike other, stable elements that formed at the same time, the abundance of a radioactive (unstable) isotope decreases all the time. The faster the decay, the less there will be left of the radioactive isotope after a certain time, so the greater will be the abundance difference when compared to a stable isotope, and the more accurate is the resulting age. Yet, for the clock to remain useful, the radioactive element must not decay too fast - there must still be enough left of it to allow an accurate measurement, even after several billion years. "Actual age measurements are restricted to the very rare objects that display huge amounts of the radioactive elements thorium or uranium," says Norbert Christlieb, co-author of the report. ESO PR Photo 23b/07 ESO PR Photo 23b/07 Uranium Line in the Spectrum of an Old Star Large amounts of these elements have been found in the star HE 1523-0901, an old, relatively bright star that was discovered within the Hamburg/ESO survey [1]. The

  16. Fossil Groups Origins III. Characterization of the sample and observational properties of fossil systems

    CERN Document Server

    Zarattini, S; Girardi, M; Castro-Rodriguez, N; Boschin, W; Aguerri, J A L; Méndez-Abreu, J; Sánchez-Janssen, R; Catalán-Torrecilla, C; Corsini, E M; del Burgo, C; D'Onghia, E; Herrera-Ruiz, N; Iglesias-Páramo, J; Bailon, E Jimenez; Muñoz, M Lozada; Napolitano, N; Vilchez, J M

    2014-01-01

    (Abridged) Fossil systems are group- or cluster-sized objects whose luminosity is dominated by a very massive central galaxy. In the current cold dark matter scenario, these objects formed hierarchically at an early epoch of the Universe and then slowly evolved until present day. That is the reason why they are called {\\it fossils}. We started an extensive observational program to characterize a sample of 34 fossil group candidates spanning a broad range of physical properties. Deep $r-$band images were taken for each candidate and optical spectroscopic observations were obtained for $\\sim$ 1200 galaxies. This new dataset was completed with SDSS DR7 archival data to obtain robust cluster membership and global properties of each fossil group candidate. For each system, we recomputed the magnitude gaps between the two brightest galaxies ($\\Delta m_{12}$) and the first and fourth ranked galaxies ($\\Delta m_{14}$) within 0.5 $R_{{\\rm 200}}$. We consider fossil systems those with $\\Delta m_{12} \\ge 2$ mag or $\\Del...

  17. Trace fossils of microbial colonization on Mars: Criteria for search and for sample return

    Science.gov (United States)

    Friedmann, E. I.

    1988-01-01

    The recent discovery of microbial trace-fossil formation in the frigid Ross Desert of Antarctica suggests that early primitive life on Mars may have left behind similar signatures. These trace fossils are apparent as chemical or physical changes in rock (or sediment) structure (or chemistry) caused by the activity of organisms. Life on Mars, if it ever existed, almost certainly did not evolve above the level of microorganisms, and this should be considered in search for fossil life. For the reasons detailed here, microbial trace fossils seem to be a better and more realistic target for search than would be true microbial fossils (remnants of cellular structures).

  18. Fossil turbulence and fossil turbulence waves can be dangerous

    CERN Document Server

    Gibson, Carl H

    2012-01-01

    Turbulence is defined as an eddy-like state of fluid motion where the inertial-vortex forces of the eddies are larger than any other forces that tend to damp the eddies out. By this definition, turbulence always cascades from small scales where vorticity is created to larger scales where turbulence fossilizes. Fossil turbulence is any perturbation in a hydrophysical field produced by turbulence that persists after the fluid is no longer turbulent at the scale of the perturbation. Fossil turbulence patterns and fossil turbulence waves preserve and propagate energy and information about previous turbulence. Ignorance of fossil turbulence properties can be dangerous. Examples include the Osama bin Laden helicopter crash and the Air France 447 Airbus crash, both unfairly blamed on the pilots. Observations support the proposed definitions, and suggest even direct numerical simulations of turbulence require caution.

  19. First fossil insectivores from Flores

    NARCIS (Netherlands)

    Hoek Ostende, van den L.W.; Berch, van der G.; Awe Due, R.

    2006-01-01

    The hominid bearing strata from the Liang Bua cave on Flores have yielded a large amount of microvertebrate remains. Among these are three mandibles of shrews, the first record of fossil insectivores from the island. The fossils, representing two different species, are not referable to any of the

  20. Likelihood of tree topologies with fossils and diversification rate estimation.

    Science.gov (United States)

    Didier, Gilles; Fau, Marine; Laurin, Michel

    2017-04-18

    Since the diversification process cannot be directly observed at the human scale, it has to be studied from the information available, namely the extant taxa and the fossil record. In this sense, phylogenetic trees including both extant taxa and fossils are the most complete representations of the diversification process that one can get. Such phylogenetic trees can be reconstructed from molecular and morphological data, to some extent. Among the temporal information of such phylogenetic trees, fossil ages are by far the most precisely known (divergence times are inferences calibrated mostly with fossils). We propose here a method to compute the likelihood of a phylogenetic tree with fossils in which the only considered time information is the fossil ages, and apply it to the estimation of the diversification rates from such data. Since it is required in our computation, we provide a method for determining the probability of a tree topology under the standard diversification model.Testing 21 our approach on simulated data shows that the maximum likelihood rate estimates from the phylogenetic tree topology and the fossil dates are almost as accurate as those obtained by taking into account all the data, including the divergence times. Moreover, they are substantially more accurate than the estimates obtained only from the exact divergence times (without taking into account the fossil record).We also provide an empirical example composed of 50 Permo-carboniferous eupelycosaur (early synapsid) taxa ranging in age from about 315 Ma (Late Carboniferous) to 270 Ma (shortly after the end of the Early Permian). Our analyses suggest a speciation (cladogenesis, or birth) rate of about 0.1 per lineage and per My, a marginally lower extinction rate, and a considerable hidden paleobiodiversity of early synapsids. © The Author(s) 2017. Published by Oxford University Press, on behalf of the Society of Systematic Biologists. All rights reserved. For Permissions, please email

  1. Stratigraphy, correlation, and age estimates for fossils from Area 123, Koobi Fora.

    Science.gov (United States)

    Feibel, Craig S; Lepre, Christopher J; Quinn, Rhonda L

    2009-08-01

    Geological data from the Bura Hasuma region at Koobi Fora provide important constraints for estimating the ages of hominin fossils recovered there, including the cranium KNM-ER 1813. Strata of the upper Burgi, KBS, and Okote members in this part of Koobi Fora reflect three depositional regimes driven by changing paleogeography through time. The upper Burgi and lowermost KBS sequence in the southern Bura Hasuma region accumulated in a lacustrine to delta front setting, with highly localized depositional patterns, limiting the lateral extent of lithostratigraphic markers. Farther north, uppermost upper Burgi through KBS member strata document a fluctuating lake margin, with complex facies patterns. This interval is marked by laterally extensive lithostratigraphic markers, including molluscan packstones, beach sandstones, and stromatolite beds. The uppermost KBS and Okote members show a transition to dominantly fluvial character, with localized and discontinuous accumulation. An age model for the richly fossiliferous Area 123 sequence demonstrates the complexity of terrestrial accumulation patterns. Early lacustrine and delta front accumulation is marked by fairly continuous sedimentation, and high accumulation rates (up to ca. 91 cm/k.yr.). The fluctuating lake margin interval reflects lower sedimentation rates coupled with intervals of exposure, decreasing accumulation significantly (to ca. 13 cm/k.yr.). The capping fluvial interval is marked by significant erosion surfaces, breaks which may drop the overall accumulation rate even lower (ca. 0.3 cm/k.yr.). The data provided here establish a geological framework at odds with a recent proposal of ages considerably younger (by ca. 250 k.yr.) for many of the fossils from Area 123 and elsewhere. Tests of age models demonstrate that the younger ages are not possible. While minor refinements to age estimates for fossils are indicated by improved chronostratigraphic control, in the case of KNM-ER 1813, an age of younger

  2. The first fossil cyphophthalmid harvestman from Baltic amber

    Directory of Open Access Journals (Sweden)

    Dunlop, Jason A.

    2011-01-01

    Full Text Available The first fossil cyphophthalmid harvestman (Opiliones: Cyphophthalmi from Palaeogene (Eocene Baltic amber is described. This is only the third fossil example of this basal harvestman lineage; the others being from the probably slightly younger Bitterfeld amber and the much older, early Cretaceous, Myanmar (Burmese amber. Although incomplete and lacking most of the appendages, the new Baltic amber fossil can be identified as a female. The somatic characters preserved, especially spiracle morphology and the coxo-genital region, allow it to be assigned with some confidence to the extant genus Siro Latreille, 1796 (Sironidae. This fossil is formally described here as Siro balticus sp. nov. It resembles modern North American Siro species more than modern European ones, and can be distinguished principally on its relatively large size and the outline form of the body.

  3. Fossilization of melanosomes via sulfurization.

    Science.gov (United States)

    McNamara, Maria E; van Dongen, Bart E; Lockyer, Nick P; Bull, Ian D; Orr, Patrick J

    2016-05-01

    Fossil melanin granules (melanosomes) are an important resource for inferring the evolutionary history of colour and its functions in animals. The taphonomy of melanin and melanosomes, however, is incompletely understood. In particular, the chemical processes responsible for melanosome preservation have not been investigated. As a result, the origins of sulfur-bearing compounds in fossil melanosomes are difficult to resolve. This has implications for interpretations of original colour in fossils based on potential sulfur-rich phaeomelanosomes. Here we use pyrolysis gas chromatography mass spectrometry (Py-GCMS), fourier transform infrared spectroscopy (FTIR) and time of flight secondary ion mass spectrometry (ToF-SIMS) to assess the mode of preservation of fossil microstructures, confirmed as melanosomes based on the presence of melanin, preserved in frogs from the Late Miocene Libros biota (NE Spain). Our results reveal a high abundance of organosulfur compounds and non-sulfurized fatty acid methyl esters in both the fossil tissues and host sediment; chemical signatures in the fossil tissues are inconsistent with preservation of phaeomelanin. Our results reflect preservation via the diagenetic incorporation of sulfur, i.e. sulfurization (natural vulcanization), and other polymerization processes. Organosulfur compounds and/or elevated concentrations of sulfur have been reported from melanosomes preserved in various invertebrate and vertebrate fossils and depositional settings, suggesting that preservation through sulfurization is likely to be widespread. Future studies of sulfur-rich fossil melanosomes require that the geochemistry of the host sediment is tested for evidence of sulfurization in order to constrain interpretations of potential phaeomelanosomes and thus of original integumentary colour in fossils.

  4. FOSSIL2 energy policy model documentation: FOSSIL2 documentation

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-10-01

    This report discusses the structure, derivations, assumptions, and mathematical formulation of the FOSSIL2 model. Each major facet of the model - supply/demand interactions, industry financing, and production - has been designed to parallel closely the actual cause/effect relationships determining the behavior of the United States energy system. The data base for the FOSSIL2 program is large, as is appropriate for a system dynamics simulation model. When possible, all data were obtained from sources well known to experts in the energy field. Cost and resource estimates are based on DOE data whenever possible. This report presents the FOSSIL2 model at several levels. Volumes II and III of this report list the equations that comprise the FOSSIL2 model, along with variable definitions and a cross-reference list of the model variables. Volume III lists the model equations and a one line definition for equations, in a short, readable format.

  5. Discontinuity surfaces in the Lower Cretaceous of the high Andes (Mendoza, Argentina): Trace fossils and environmental implications

    Science.gov (United States)

    Mangano, M. G.; Buatois, L. A.

    The paleoecologic and paleoenvironmental significance of trace fossils related to discontinuity surfaces in the Lower Cretaceous marine deposits of the Aconcagua area are analysed here. Carbonate-evaporite shoaling-upward cycles, developed by high organic production in a shallow hypersaline restricted environment, make up the section. Two types of cycles are defined, being mainly distinguished by their subtidal unit. Cycle I begins with a highly dolomitized lower subtidal unit (Facies A), followed upward by an intensely bioturbated upper subtidal unit (Facies B). The nodular packstone facies (B 1) is capped by a discontinuity surface (firmground or hardground) and occasionally overlain by an oystreid bed (Facies C). Cycle II is characterized by a pelletoidal subtidal unit (Facies B 2) with an abnormal salinity impoverished fauna. Both cycles end with intertidal to supratidal evaporite deposits (Facies D and E, respectively). Attention is particularly focused on cycle I due to its ichologic content. The mode of preservation and the distribution of trace fossils in nodular packstone facies are controlled by original substrate consolidation. Thalassinoides paradoxicus (pre-omission suite) represents colonization in a soft bottom, while Thalassinoides suevicus (omission suite pre-lithification) is apparently restricted to firm substrates. When consolidation processes are interrupted early, only an embryonic hard-ground that represents a minor halt in sedimentation was developed. Sometimes, consolidation processes continued leading to an intraformational hardground. Colonization by Trypanites solitarius (omission suite post-lithification) and Exogyra-like oystreids possibly characterizes hard substrate stage. When two discontinuity surfaces follow closely, a post-omission suite may be defined in relation to the lower cemented surface. As trace fossils are so closely related to changes in the degree of bottom lithification, they prove to be very useful as indicators of

  6. Bed rest during pregnancy

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/patientinstructions/000581.htm Bed rest during pregnancy To use the sharing features on ... few days or weeks. This is called bed rest. Bed rest used to be recommended routinely for ...

  7. Depositional model of Early Permian reef-island ocean inEastern Kunlun

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Many fusulinid fossils have been found in thin- to middle-bedded limestones which aredistributed between the Early Permian limestone hills and formerly considered as Early Triassic.The fusulinid fossils, identified as Neoshwagerina sp., Verbeekina sp. and Schwagerina sp., canalso be found in massive limestone hills. At the same time, Early Permian radiolarian chert of deepbasin facies was discovered in Animaqing. All the above show that the massive limestone hills,thin- to middle-bedded limestones and radiolarian chert belong to syndeposits in Early Permianocean. The sediments in the study area can roughly be divided into three types: shallow facies,basin facies and transitional facies. The carbonate buildup can be subdivided into massive bioclas-tic limestone and reef framestone. Basin facies contains thin- or middle-bedded limestone, abyssalred mudstone or ooze, blue-green mudstone and radiolarian chert. Transitional facies includes reeftalus and platformal skirt facies. The Early Permian ocean in Eastern Kunlun is recognized as akind of reef-island ocean environment according to distribution and composition of different facies.The reef-island ocean in Eastern Kunlun is characterized by reef islands (or carbonate buildups)alternating with basins, complicated sea-floor topography, sharp facial change and well-developedreefs

  8. Age of the Kalana Lagerstätte, early Silurian, Estonia

    Directory of Open Access Journals (Sweden)

    Peep Männik

    2016-05-01

    Full Text Available The Kalana quarry in central Estonia is known for its exceptionally well-preserved non-calcified algal and other fossils. The interval with the fossil Konservat Lagerstätte in the Kalana section has previously been tentatively dated as early Aeronian. Recent findings of graptolites now enable more precise dating of these beds. The strata yielding the Lagerstätte are not older than the mid-Aeronian and correspond to the Pribylograptus leptotheca graptolite Biozone. In terms of conodont biostratigraphy they correlate with the middle of the Pranognathus tenuis conodont Biozone. It has also become evident that the uppermost Jõgeva Beds of the Nurmekund Formation, and probably also the uppermost Ikla Member of the Saarde Formation, are younger than previously thought and correlate with the Pribylograptus leptotheca graptolite Biozone. Our data additionally indicate that the conodont genus Aulacognathus had appeared by the mid-Aeronian.

  9. How to Find Bed Bugs

    Science.gov (United States)

    Find and correctly identify an infestation early before it becomes widespread. Look for rusty or reddish stains and pinpoint dark spots on bed sheets or mattresses, and search for bugs near the piping, seams and tags of the mattress and box spring.

  10. The legacy of fossil fuels.

    Science.gov (United States)

    Armaroli, Nicola; Balzani, Vincenzo

    2011-03-01

    Currently, over 80% of the energy used by mankind comes from fossil fuels. Harnessing coal, oil and gas, the energy resources contained in the store of our spaceship, Earth, has prompted a dramatic expansion in energy use and a substantial improvement in the quality of life of billions of individuals in some regions of the world. Powering our civilization with fossil fuels has been very convenient, but now we know that it entails severe consequences. We treat fossil fuels as a resource that anyone anywhere can extract and use in any fashion, and Earth's atmosphere, soil and oceans as a dump for their waste products, including more than 30 Gt/y of carbon dioxide. At present, environmental legacy rather than consistence of exploitable reserves, is the most dramatic problem posed by the relentless increase of fossil fuel global demand. Harmful effects on the environment and human health, usually not incorporated into the pricing of fossil fuels, include immediate and short-term impacts related to their discovery, extraction, transportation, distribution, and burning as well as climate change that are spread over time to future generations or over space to the entire planet. In this essay, several aspects of the fossil fuel legacy are discussed, such as alteration of the carbon cycle, carbon dioxide rise and its measurement, greenhouse effect, anthropogenic climate change, air pollution and human health, geoengineering proposals, land and water degradation, economic problems, indirect effects on the society, and the urgent need of regulatory efforts and related actions to promote a gradual transition out of the fossil fuel era. While manufacturing sustainable solar fuels appears to be a longer-time perspective, alternatives energy sources already exist that have the potential to replace fossil fuels as feedstocks for electricity production. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Problems with fossil fuels

    Energy Technology Data Exchange (ETDEWEB)

    Smedsvig, K.G. [AEDENAT, Madrid (Spain)

    1995-10-01

    Three coal-fired power plants are responsible for 60% of the Spanish emissions of sulphur dioxide. These are: the As Pontes and the Meirama plants fired with brown lignite and the Andorra plant fired with black lignite. Permissible emission limits of SO{sub 2} were increased from 8000 mg/m{sup 3} to 12,500 mg/m{sup 3} when the As Pontes and Andorra plants were put into operation. As Pontes will change from brown lignite to imported hard coal to reduce sulphur emissions but this coal will have to be hauled 50 km by 750 20-ton trucks, or one every other minute in each direction, around the clock, from port to power plant. The Andorra complex, will be equipped for flue gas desulphurisation. Two new plants included in the programme of the state-owned ENDESA power company include a 175 MW generator with fluidised-bed combustion and a 350 MW installation for coal gasification. ENDESA has been criticised by AEDENAT the Spanish environmentalist group for continued investment in nuclear plants and little use of renewable resources. This short paper is based on an article by AEDENAT entitled `Atmospheric pollutants from electric power generation in peninsular Spain`. 1 ref., 1 fig.

  12. Dating fossil opal phytoliths

    Energy Technology Data Exchange (ETDEWEB)

    Lentfer, C.; Boyd, B. [Southern Cross University, Lismore, NSW (Australia). School of Resource Science and Management; Torrence, R. [Australian Museum, Sydney, NSW (Australia). Division of Anthropology

    1999-11-01

    Full text: Opal phytoliths are microscopic silica bodies formed by the precipitation of hydrated silica dioxide (SiO{sub 2}nH{sub 2}0) in, around and between cell walls. They are relatively resistant to degradation in most environments and thus, can occur in large quantities in palaeosediments. Consequently, they are valuable tools for environmental reconstruction. Furthermore, phytoliths are often the only recoverable organic material in well oxidised sediments, the occluded carbon provides the opportunity for dating sediment whose ages have previously been difficult to determine, and thus, increase the potential for fine resolution determination of environmental change. This poster describes the results of an investigation assessing the viability of AMS radiocarbon dating of fossil phytolith inclusions using samples from Garua Island, West New Britain, PNG. Thirteen phytolith samples, isolated from sediments previously dated using tephrastratigraphy and C14 dating of macroremains of nutshells and wood charcoal, were used in the analysis. As a control measure, thirteen parallel samples of microscopic charcoal were also dated using AMS. The results show that the AMS dates for the microscopic charcoal samples are consistent with ages anticipated from the other dating methods, for all but one sample. However, the dates for eight of the thirteen phytolith samples are considerably younger than expected. This bias could be explained by several factors, including downwashing of phytolith through soils, bioturbation, carbon exchange through the siliceous matrix of the phytolith bodies, and contamination from extraneous sources of modern carbon retained in the samples. Research is currently focusing on the investigation of these issues and selected samples are in the process of being retreated with strong oxidising agents to clear contaminants prior to re-dating. Further to this, a full investigation of one profile with a long sequence is underway. High concentrations of

  13. Contemporaneous trace and body fossils from a late Pleistocene Lakebed in Victoria, Australia, allow assessment of bias in the fossil record.

    Science.gov (United States)

    Camens, Aaron Bruce; Carey, Stephen Paul

    2013-01-01

    The co-occurrence of vertebrate trace and body fossils within a single geological formation is rare and the probability of these parallel records being contemporaneous (i.e. on or near the same bedding plane) is extremely low. We report here a late Pleistocene locality from the Victorian Volcanic Plains in south-eastern Australia in which demonstrably contemporaneous, but independently accumulated vertebrate trace and body fossils occur. Bite marks from a variety of taxa are also present on the bones. This site provides a unique opportunity to examine the biases of these divergent fossil records (skeletal, footprints and bite marks) that sampled a single fauna. The skeletal record produced the most complete fauna, with the footprint record indicating a markedly different faunal composition with less diversity and the feeding traces suggesting the presence, amongst others, of a predator not represented by either the skeletal or footprint records. We found that the large extinct marsupial predator Thylacoleo was the only taxon apparently represented by all three records, suggesting that the behavioral characteristics of large carnivores may increase the likelihood of their presence being detected within a fossil fauna. In contrast, Diprotodon (the largest-ever marsupial) was represented only by trace fossils at this site and was absent from the site's skeletal record, despite its being a common and easily detected presence in late Pleistocene skeletal fossil faunas elsewhere in Australia. Small mammals absent from the footprint record for the site were represented by skeletal fossils and bite marks on bones.

  14. The Fossil Phase in the Life of a Galaxy Group

    CERN Document Server

    von Benda-Beckmann, Alexander M; Gottloeber, Stefan; Hoeft, Matthias; Khalatyan, Arman; Klypin, Anatoly; Mueller, Volker

    2007-01-01

    We investigate the origin and evolution of fossil groups in a concordance LCDM cosmological simulation. We consider haloes with masses between $(1-5)\\times10^{13} \\hMsun$ and study the physical mechanisms that lead to the formation of the large gap in magnitude between the brightest and the second most bright group member, which is typical for these fossil systems. Fossil groups are found to have high dark matter concentrations, which we can relate to their early formation time. The large magnitude-gaps arise after the groups have build up half of their final mass, due to merging of massive group members. We show that the existence of fossil systems is primarily driven by the relatively early infall of massive satellites, and that we do not find a strong environmental dependence for these systems. In addition, we find tentative evidence for fossil group satellites falling in on orbits with typically lower angular momentum, which might lead to a more efficient merger onto the host. We find a population of grou...

  15. Fossil and non-fossil source contributions to atmospheric carbonaceous aerosols during extreme spring grassland fires in Eastern Europe

    Directory of Open Access Journals (Sweden)

    V. Ulevicius

    2015-09-01

    Full Text Available In early spring the Baltic region is frequently affected by high pollution events due to biomass burning in that area. Here we present a comprehensive study to investigate the impact of biomass/grass burning (BB on the evolution and composition of aerosol in Preila, Lithuania, during springtime open fires. Non-refractory submicron particulate matter (NR-PM1 was measured by an Aerodyne aerosol chemical speciation monitor (ACSM and a source apportionment with the multilinear engine (ME-2 running the positive matrix factorization (PMF model was applied to the organic aerosol fraction to investigate the impact of biomass/grass burning. Satellite observations over regions of biomass burning activity supported the results and identification of air mass transport to the area of investigation. Sharp increases in biomass burning tracers, such as levoglucosan up to 683 ng m−3 and black carbon (BC up to 17 μg m−3 were observed during this period. A further separation between fossil and non-fossil primary and secondary contributions was obtained by coupling ACSM PMF results and radiocarbon (14C measurements of the elemental (EC and organic (OC carbon fractions. Non-fossil organic carbon (OCnf was the dominant fraction of PM1, with the primary (POCnf and secondary (SOCnf fractions contributing 26–44 % and 13–23 % to the TC, respectively. 5–8 % of the TC had a primary fossil origin (POCf, whereas the contribution of fossil secondary organic carbon (SOCf was 4–13 %. Non-fossil EC (ECnf and fossil EC (ECf ranged from 13–24 % and 7–12 %, respectively. Isotope ratio of stable carbon and nitrogen isotopes were used to distinguish aerosol particles associated with solid and liquid fossil fuel burning.

  16. Travels with the Fossil Hunters

    Science.gov (United States)

    Whybrow, Peter J.

    2000-04-01

    Whether dodging bullets in West Africa, or rabid dogs in Pakistan, surviving yak-butter tea in Tibet, or eating raw fish in China, the life of a globe-trotting fossil hunter is often hazardous and always filled with surprises. Travels with the Fossil Hunters lets readers share the wonder, joys of discovery, and excitement of these intrepid scientists. Packed with more than 100 beautiful, full-color photographs, the volume takes readers on twelve expeditions to remote parts of the world in search of diverse fossil remains, from those of dinosaurs to human ancestors. Each expedition by paleontologists from London's Natural History Museum reveals the problems and challenges of working in extreme conditions, from the deserts of the Sahara and Yemen to the frozen wastes of Antarctica, from the mountains of India to the forests of Latvia. Along the way they also describe the paleontology and geology of the countries they visit and the scientific reasons for their expeditions. With a foreword from Sir David Attenborough and an introduction from Richard Fortey, this fascinating book will appeal to amateur and professional fossil hunters alike and to readers interested in accounts of exotic locales. Peter Whybrow is a research scientist at the Natural History Museum, London. His research interests include Arabian Miocene vertebrates, paleoclimates, paleogeography, and biotic diversity. He is senior editor with A. Hill of Fossil Vertebrates of Arabia (Yale University Press, New Haven, 1999).

  17. Turbulence and diffusion fossil turbulence

    CERN Document Server

    Gibson, C H

    2000-01-01

    Fossil turbulence processes are central to turbulence, turbulent mixing, and turbulent diffusion in the ocean and atmosphere, in astrophysics and cosmology, and in most other natural flows. George Gamov suggested in 1954 that galaxies might be fossils of primordial turbulence produced by the Big Bang. John Woods showed that breaking internal waves on horizontal dye sheets in the interior of the stratified ocean form highly persistent remnants of these turbulent events, which he called fossil turbulence. The dark mixing paradox of the ocean refers to undetected mixing that must exist somewhere to explain why oceanic scalar fields like temperature and salinity are so well mixed, just as the dark matter paradox of galaxies refers to undetected matter that must exist to explain why rotating galaxies don't fly apart by centrifugal forces. Both paradoxes result from sampling techniques that fail to account for the extreme intermittency of random variables involved in self-similar, nonlinear, cascades over a wide ra...

  18. FOSSIL2 energy policy model documentation: FOSSIL2 documentation

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-10-01

    This report discusses the structure, derivations, assumptions, and mathematical formulation of the FOSSIL2 model. Each major facet of the model - supply/demand interactions, industry financing, and production - has been designed to parallel closely the actual cause/effect relationships determining the behavior of the United States energy system. The data base for the FOSSIL2 program is large, as is appropriate for a system dynamics simulation model. When possible, all data were obtained from sources well known to experts in the energy field. Cost and resource estimates are based on DOE data whenever possible. This report presents the FOSSIL2 model at several levels. Volumes II and III of this report list the equations that comprise the FOSSIL2 model, along with variable definitions and a cross-reference list of the model variables. Volume II provides the model equations with each of their variables defined, while Volume III lists the equations, and a one line definition for equations, in a shorter, more readable format.

  19. NMR potentials for studying physical processes in fossil coals

    Energy Technology Data Exchange (ETDEWEB)

    Alekseev, Anatolii D; Ul' yanova, Ekaterina V; Vasilenko, Tat' yana A [Institute of Mining Processes Physics, National Academy of Sciences of Ukraine, Donetsk (Ukraine)

    2005-11-30

    High-resolution, pulsed, and wide-line NMR studies of fossil coals are reviewed. Coal substance conversion due to outbursts is discussed. Results on water and methane interactions with coal substance, which provide insight into the dynamic characteristics of boundary water, the location of methane in coal structure, and water and methane's hazard implications for coal beds (gas- or geodynamic phenomena) are presented; these are shown to have potential for predicting and preventing life threatening situations. (instruments and methods of investigation)

  20. Early

    Directory of Open Access Journals (Sweden)

    Kamel Abd Elaziz Mohamed

    2014-04-01

    Conclusion: Early PDT is recommended for patients who require prolonged tracheal intubation in the ICU as outcomes like the duration of mechanical ventilation length of ICU stay and hospital stay were significantly shorter in early tracheostomy.

  1. Fossil Energy Program. Progress report for October 1979

    Energy Technology Data Exchange (ETDEWEB)

    McNeese, L.E.

    1979-12-01

    This report, the sixty-third of a series, is a compendium of monthly progress reports for the ORNL research and development programs that are in support of the increased utilization of coal and other fossil fuel alternatives to oil and gas as sources of clean energy. The projects reported this month include those for coal conversion development, materials engineering, a coal equipment test program, an atmospheric fluid bed combustor for cogeneration, engineering studies and technical support, process and program analysis, environmental assessment studies, magnetic beneficiation of dry pulverized coal, technical support to the TVA fluid bed combustion program, coal cogeneration/district heating plant assessment, chemical research and development, and technical support to major liquefaction projects.

  2. Fossil Energy Program. Progress report for September 1979

    Energy Technology Data Exchange (ETDEWEB)

    McNeese, L.E.

    1979-11-01

    This report - the sixty-second of a series - is a compendium of monthly progress reports for the ORNL research and development programs that are in support of the increased utilization of coal and other fossil fuel alternatives to oil and gas as sources of clean energy. The projects reported this month include those for coal conversion development, materials engineering, a coal equipment test program, an atmospheric fluidized bed combustor for cogeneration, engineering studies and technical support, process and program analysis, environmental assessment studies, magnetic beneficiation of dry pulverized coal, technical support to the TVA fluidized bed combustion program, coal cogeneration/district heating plant assessment, chemical research and development, and technical support to major liquefaction projects.

  3. Fossil Energy Program. Progress report for August 1979

    Energy Technology Data Exchange (ETDEWEB)

    McNeese, L.E.

    1979-10-01

    This report - the sixty-first of a series - is a compendium of monthly progress reports for the ORNL research and development programs that are in support of the increased utilization of coal and other fossil fuel alternatives to oil and gas as sources of clean energy. The projects reported this month include those for coal conversion development, materials engineering, a coal equipment test program, an atmospheric fluid bed combustor for cogeneration, engineering studies and technical support, process and program analysis, environmental assessment studies, magnetic beneficiation of dry pulverized coal, technical support to the TVA fluid bed combustion program, coal cogeneration/district heating plant assessment, chemical research and development, and technical support to major liquefaction projects.

  4. Fossil Polypodiaceae and their spores

    NARCIS (Netherlands)

    Uffelen, van Gerda A.

    1991-01-01

    In this publication emphasis is laid on the modern definition of the family Polypodiaceae (Filicales), which is based on an extensive study of Recent material and which is much restricted with respect to older circumscriptions of the family as usually applied by palaeobotanists. Fossils of fems belo

  5. Equatorial spread F fossil plumes

    Directory of Open Access Journals (Sweden)

    S. L. Ossakow

    2010-11-01

    Full Text Available Behaviour of equatorial spread F (ESF fossil plumes, i.e., ESF plumes that have stopped rising, is examined using the NRL SAMI3/ESF three-dimensional simulation code. We find that fossil bubbles, plasma density depletions associated with fossil plumes, can persist as high-altitude equatorial depletions even while being "blown" by zonal winds. Corresponding airglow-proxy images of fossil plumes, plots of electron density versus longitude and latitude at a constant altitude of 288 km, are shown to partially "fill in" in most cases, beginning with the highest altitude field lines within the plume. Specifically, field lines upon which the E field has fallen entirely to zero are affected and only the low altitude (≤600 km portion if each field line fills in. This suggests that it should be possible to observe a bubble at high altitude on a field line for which the corresponding airglow image no longer shows a depletion. In all cases ESF plumes stop rising when the flux-tube-integrated ion mass density inside the upper edge of the bubble is equal to that of the nearby background, further supporting the result of Krall et al. (2010b.

  6. Fossil Polypodiaceae and their spores

    NARCIS (Netherlands)

    Uffelen, van Gerda A.

    1991-01-01

    In this publication emphasis is laid on the modern definition of the family Polypodiaceae (Filicales), which is based on an extensive study of Recent material and which is much restricted with respect to older circumscriptions of the family as usually applied by palaeobotanists. Fossils of fems

  7. Fossil Energy: Drivers and Challenges.

    Science.gov (United States)

    Friedmann, Julio

    2007-04-01

    Concerns about rapid economic growth, energy security, and global climate change have created a new landscape for fossil energy exploration, production, and utilization. Since 85% of primary energy supply comes from fossil fuels, and 85% of greenhouse gas emissions come from fossil fuel consumption, new and difficult technical and political challenges confront commercial, governmental, and public stakeholders. As such, concerns over climate change are explicitly weighed against security of international and domestic energy supplies, with economic premiums paid for either or both. Efficiency improvements, fuel conservation, and deployment of nuclear and renewable supplies will help both concerns, but are unlikely to offset growth in the coming decades. As such, new technologies and undertakings must both provide high quality fossil energy with minimal environmental impacts. The largest and most difficult of these undertakings is carbon management, wherein CO2 emissions are sequestered indefinitely at substantial incremental cost. Geological formations provide both high confidence and high capacity for CO2 storage, but present scientific and technical challenges. Oil and gas supply can be partially sustained and replaced through exploitation of unconventional fossil fuels such as tar-sands, methane hydrates, coal-to-liquids, and oil shales. These fuels provide enormous reserves that can be exploited at current costs, but generally require substantial energy to process. In most cases, the energy return on investment (EROI) is dropping, and unconventional fuels are generally more carbon intensive than conventional, presenting additional carbon management challenges. Ultimately, a large and sustained science and technology program akin to the Apollo project will be needed to address these concerns. Unfortunately, real funding in energy research has dropped dramatically (75%) in the past three decades, and novel designs in fission and fusion are not likely to provide any

  8. Improving large-scale groundwater models by considering fossil gradients

    Science.gov (United States)

    Schulz, Stephan; Walther, Marc; Michelsen, Nils; Rausch, Randolf; Dirks, Heiko; Al-Saud, Mohammed; Merz, Ralf; Kolditz, Olaf; Schüth, Christoph

    2017-05-01

    Due to limited availability of surface water, many arid to semi-arid countries rely on their groundwater resources. Despite the quasi-absence of present day replenishment, some of these groundwater bodies contain large amounts of water, which was recharged during pluvial periods of the Late Pleistocene to Early Holocene. These mostly fossil, non-renewable resources require different management schemes compared to those which are usually applied in renewable systems. Fossil groundwater is a finite resource and its withdrawal implies mining of aquifer storage reserves. Although they receive almost no recharge, some of them show notable hydraulic gradients and a flow towards their discharge areas, even without pumping. As a result, these systems have more discharge than recharge and hence are not in steady state, which makes their modelling, in particular the calibration, very challenging. In this study, we introduce a new calibration approach, composed of four steps: (i) estimating the fossil discharge component, (ii) determining the origin of fossil discharge, (iii) fitting the hydraulic conductivity with a pseudo steady-state model, and (iv) fitting the storage capacity with a transient model by reconstructing head drawdown induced by pumping activities. Finally, we test the relevance of our approach and evaluated the effect of considering or ignoring fossil gradients on aquifer parameterization for the Upper Mega Aquifer (UMA) on the Arabian Peninsula.

  9. Bed Bug Infestations and Control Practices in China: Implications for Fighting the Global Bed Bug Resurgence

    Directory of Open Access Journals (Sweden)

    Changlu Wang

    2011-04-01

    Full Text Available The bed bug resurgence in North America, Europe, and Australia has elicited interest in investigating the causes of the widespread and increasing infestations and in developing more effective control strategies. In order to extend global perspectives on bed bug management, we reviewed bed bug literature in China by searching five Chinese language electronic databases. We also conducted telephone interviews of 68 pest control firms in two cities during March 2011. In addition, we conducted telephone interviews to 68 pest control companies within two cities in March 2011. Two species of bed bugs (Cimex lectularius L. and Cimex hemipterus (F. are known to occur in China. These were common urban pests before the early1980s. Nationwide “Four-Pest Elimination” campaigns (bed bugs being one of the targeted pests were implemented in China from 1960 to the early 1980s. These campaigns succeeded in the elimination of bed bug infestations in most communities. Commonly used bed bug control methods included applications of hot water, sealing of bed bug harborages, physical removal, and applications of residual insecticides (mainly organophosphate sprays or dusts. Although international and domestic travel has increased rapidly in China over the past decade (2000–2010, there have only been sporadic new infestations reported in recent years. During 1999–2009, all documented bed bug infestations were found in group living facilities (military dormitories, worker dormitories, and prisons, hotels, or trains. One city (Shenzhen city near Hong Kong experienced significantly higher number of bed bug infestations. This city is characterized by a high concentration of migratory factory workers. Current bed bug control practices include educating residents, washing, reducing clutter, putting items under the hot sun in summer, and applying insecticides (pyrethroids or organophosphates. There have not been any studies or reports on bed bug insecticide

  10. Bed Bugs - Multiple Languages

    Science.gov (United States)

    ... Are Here: Home → Multiple Languages → All Health Topics → Bed Bugs URL of this page: https://medlineplus.gov/languages/ ... V W XYZ List of All Topics All Bed Bugs - Multiple Languages To use the sharing features on ...

  11. Bed Bugs and Schools

    Science.gov (United States)

    Bed bugs have long been a pest – feeding on blood, causing itchy bites and generally irritating their human hosts. They are successful hitchhikers, and can move from an infested site to furniture, bedding, baggage, boxes, and clothing.

  12. Sanitary effects of fossil fuels; Effets sanitaires des combustibles fossiles

    Energy Technology Data Exchange (ETDEWEB)

    Nifenecker, H. [Centre National de la Recherche Scientifique (IN2P3/CNRS), 38 - Grenoble (France)

    2006-07-01

    In this compilation are studied the sanitary effects of fossil fuels, behavioral and environmental sanitary risks. The risks in connection with the production, the transport and the distribution(casting) are also approached for the oil(petroleum), the gas and the coal. Accidents in the home are evoked. The risks due to the atmospheric pollution are seen through the components of the atmospheric pollution as well as the sanitary effects of this pollution. (N.C.)

  13. Introduction to Bed Bugs

    Science.gov (United States)

    ... that there are ways to control bed bugs. Getting good, solid information is the first step in both prevention and control. While there is no chemical quick fix, there are effective strategies to control bed bugs involving both non-chemical and chemical methods. Bed bugs can be hard to find and ...

  14. Looking at Fossils in New Ways

    Science.gov (United States)

    Flannery, Maura C.

    2005-01-01

    Existing fossils could be studied from a different prospective with the use of new methods of analysis for gathering more information. The new techniques of studying fossils binds the new and the old techniques and information and provides another way to look at fossils.

  15. Cycads: Fossil evidence of late paleozoic origin

    Science.gov (United States)

    Mamay, S.H.

    1969-01-01

    Plant fossils from Lower Permian strata of the southwestern United States have been interpreted as cycadalean megasporophylls. They are evidently descended from spermopterid elements of the Pennsylvanian Taeniopteris complex; thus the known fossil history of the cycads is extended from the Late Triassic into the late Paleozoic. Possible implications of the Permian fossils toward evolution of the angiosperm carpel are considered.

  16. Fossil Leaves and Fossil Leaf n-Alkanes: Reconstructing the First Closed Canopied Rainforests

    Science.gov (United States)

    Graham, H. V.; Freeman, K. H.

    2013-12-01

    Although the age and location is disputed, the rise of the first closed-canopy forest is likely linked with the expansion of angiosperms in the late Cretacous or early Cenozoic. The carbon isotope 'canopy effect' reflects the extent of canopy closure, and is well documented in δ13C values of the leaves and leaf lipids in modern forests. To test the extent of canopy closure among the oldest documented angiosperm tropical forests, we analyzed isotopic characteristics of leaf fossils and leaf waxes from the Guaduas and Cerrejón Formations. The Guaduas Fm. (Maastrichtian) contains some of the earliest angiosperm fossils in the Neotropics, and both leaf morphology and pollen records at this site suggest an open-canopy structure. The Cerrejón Fm. (Paleocene) contains what are believed to be the first recorded fossil leaves from a closed-canopy forest. We analyzed the bulk carbon isotope content (δ13Cleaf) of 199 fossil leaves, as well as the n-alkane concentration and chain-length distribution, and δ13C of alkanes (δ13Clipid) of 73 fossil leaves and adjacent sediment samples. Fossil leaves are dominated by eudicots and include ten modern plant families (Apocynaceae, Bombaceae, Euphorbaceae, Fabaceae, Lauraceae, Malvaceae, Meliaceae, Menispermaceae, Moraceae, Sapotaceae). We interpreted extent of canopy coverage based on the range of δ13Cleaf values. The narrow range of δ13C values in leaves from the Guaduas Fm (2.7‰) is consistent with an open canopy. A significantly wider range in values (6.3‰) suggests a closed-canopy signature for site 0315 of the Cerrejón Fm,. In contrast, at Site 0318, a lacustrine deposit, leaves had a narrow range (3.3‰) in δ13C values, and this is not consistent with a closed-canopy, but is consistent with leaf assemblages from a forest edge. Leaves that accumulate in lake sediments tend to be biased toward plants living at the lake edge, which do not experience closed-canopy conditions, and do not express the isotopic

  17. Preliminary elemental analysis of fossil insects from the Middle Jurassic of Daohugou, Inner Mongolia and its taphonomic implications

    Institute of Scientific and Technical Information of China (English)

    WANG Bo; LI JianFeng; FANG Yan; ZHANG HaiChun

    2009-01-01

    Fossil insects from the Middle Jurassic of Daohugou, Inner Mongolia were investigated using Scanning Electron Microscope (SEM) for the first time, and portions and distribution of some elements in com-pression and pyrited fossils were also revealed by X-ray Energy Dispersive Spectroscopy (EDS) at-tached to SEM. Most of compression fossil insects from the Daohugou Biota are preserved in organic remains (diagenetic products of the original organic components). A small part of compression fossils retain a comparatively high Fe concentration which probably resulted from the absorption of Fe by biopolymers during the decaying period. Pyritized insect fossils suggest that the "fossil envelop" model found in the Early Cretaceous Jehol Biota probably also occurs in the Daohugou Biota. Different preservation modes show various mechanisms of fossilization, and also suggest that several different microenvironments are present in Daohugou palaeolakes.

  18. Using more than the oldest fossils: dating osmundaceae with three Bayesian clock approaches.

    Science.gov (United States)

    Grimm, Guido W; Kapli, Paschalia; Bomfleur, Benjamin; McLoughlin, Stephen; Renner, Susanne S

    2015-05-01

    A major concern in molecular clock dating is how to use information from the fossil record to calibrate genetic distances from DNA sequences. Here we apply three Bayesian dating methods that differ in how calibration is achieved-"node dating" (ND) in BEAST, "total evidence" (TE) dating in MrBayes, and the "fossilized birth-death" (FBD) in FDPPDiv-to infer divergence times in the royal ferns. Osmundaceae have 16-17 species in four genera, two mainly in the Northern Hemisphere and two in South Africa and Australasia; they are the sister clade to the remaining leptosporangiate ferns. Their fossil record consists of at least 150 species in ∼17 genera. For ND, we used the five oldest fossils, whereas for TE and FBD dating, which do not require forcing fossils to nodes and thus can use more fossils, we included up to 36 rhizomes and frond compression/impression fossils, which for TE dating were scored for 33 morphological characters. We also subsampled 10%, 25%, and 50% of the 36 fossils to assess model sensitivity. FBD-derived divergence ages were generally greater than those inferred from ND; two of seven TE-derived ages agreed with FBD-obtained ages, the others were much younger or much older than ND or FBD ages. We prefer the FBD-derived ages because they best fit the Osmundales fossil record (including Triassic fossils not used in our study). Under the preferred model, the clade encompassing extant Osmundaceae (and many fossils) dates to the latest Paleozoic to Early Triassic; divergences of the extant species occurred during the Neogene. Under the assumption of constant speciation and extinction rates, the FBD approach yielded speciation and extinction rates that overlapped those obtained from just neontological data. However, FBD estimates of speciation and extinction are sensitive to violations in the assumption of continuous fossil sampling; therefore, these estimates should be treated with caution.

  19. Collaborative Strategy on Bed Bugs

    Science.gov (United States)

    The Collaborative Strategy on Bed Bugs was developed by the Federal Bed Bug Workgroup to clarify the federal role in bed bug control and highlight ways that government, community, academia and private industry can work together on bed bug issues.

  20. 四川珙县石碑恐龙化石埋藏地红层分子化石特征及其古环境意义%Features of molecular fossils at the Shibei dinosaur fossil site-Early Jurassic red beds-in Gongxian, Sichuan, and their paleoenvironmental significance

    Institute of Scientific and Technical Information of China (English)

    梁斌; 王全伟; 阚泽忠; 朱兵

    2006-01-01

    利用气相色谱-质谱仪(GC/MS)从四川珙县石碑恐龙化石埋藏地早侏罗世红层中检出了包括正构烷烃、类异戊二烯烃、长链三环萜、藿烷和甾烷等系列分子化石,这些分子化石来源于低等菌藻类生物和水生、陆生高等植物.利用这些分子化石的特征讨论了恐龙生活时代的古环境特征.姥鲛烷与植烷的比值(Pr/Ph)表明该恐龙化石埋藏地的沉积环境应为淡水、弱氧化的湖泊环境.所研究样品高碳数的正构烷烃均以与水生大型植物有关的C25为主峰,并具有来自陆生高等植物的C27~C31正构烷烃,反映出研究区湖盆水体中发育水生高等植物,周围陆地上发育木本和草本植物的古植物特征,体现了分子化石在恢复古环境研究方面的潜力.

  1. An extraordinary gobioid fish fossil from Southern France.

    Directory of Open Access Journals (Sweden)

    Christoph Gierl

    Full Text Available BACKGROUND: The classification of gobioid fishes is still under discussion. Several lineages, including the Eleotridae and Butidae, remain difficult to characterize because synapomorphies are rare (Eleotridae or have not yet been determined (Butidae. Moreover, the fossil record of these groups is scarce. RESULTS: Exceptionally well-preserved fish fossils with otoliths in situ from uppermost Oligocene sediments (≈23-24 Mio. y. ago in Southern France provide the most in-depth description of a fossil gobioid to date. The species was initially described as Cottus aries Agassiz, then transferred to †Lepidocottus Sauvage, and subsequently assigned to Gobius. Based on a comparative analysis of meristic, osteological and otolith data, this species most likely is a member of the family Butidae. This discovery is important because it represents the first record of a fossil butid fish based on articulated skeletons from Europe. SIGNIFICANCE: The Butidae and Eleotridae are currently distributed in W-Africa, Madagascar, Asia and Australia, but they do not appear in Europe and also not in the Mediterranean Sea. The new results indicate that several species of the Butidae thrived in Europe during the Oligocene and Early Miocene. Similar to the recent Butidae and Eleotridae, these fishes were adapted to a wide range of salinities and thrived in freshwater, brackish and marginal marine habitats. The fossil Butidae disappeared from Europe and the Mediterranean and Paratethys areas during the Early Miocene, due probably to their lack of competitiveness compared to other Gobioidei that radiated during this period of time. In addition, this study documents the great value of otoliths for gobioid systematics.

  2. A Miocene ostrich fossil from Gansu Province, northwest China

    Institute of Scientific and Technical Information of China (English)

    HOU Lianhai; ZHOU Zhonghe; ZHANG Fucheng; WANG Zhao

    2005-01-01

    @@ A pelvic skeleton, recognized as a large terrestrial bird in the field, was recently collected by our paleomammalogist colleagues from the Institute of Vertebrate Paleontology and Paleoanthropology from the late Miocene sandy mudstones in the Linxia Basin in Gansu Province, northwest China. We have further referred this bird to as an early representative of ostrich. Ostrich fossils usually coexisted with the famous Hipparion Fauna from the Miocene to Pliocene.

  3. The eukaryotic fossil record in deep time

    Science.gov (United States)

    Butterfield, N.

    2011-12-01

    Eukaryotic organisms are defining constituents of the Phanerozoic biosphere, but they also extend well back into the Proterozoic record, primarily in the form of microscopic body fossils. Criteria for identifying pre-Ediacaran eukaryotes include large cell size, morphologically complex cell walls and/or the recognition of diagnostically eukaryotic cell division patterns. The oldest unambiguous eukaryote currently on record is an acanthomorphic acritarch (Tappania) from the Palaeoproterozoic Semri Group of central India. Older candidate eukaryotes are difficult to distinguish from giant bacteria, prokaryotic colonies or diagenetic artefacts. In younger Meso- and Neoproterozoic strata, the challenge is to recognize particular grades and clades of eukaryotes, and to document their macro-evolutionary expression. Distinctive unicellular forms include mid-Neoproterozoic testate amoebae and phosphate biomineralizing 'scale-microfossils' comparable to an extant green alga. There is also a significant record of seaweeds, possible fungi and problematica from this interval, documenting multiple independent experiments in eukaryotic multicellularity. Taxonomically resolved forms include a bangiacean red alga and probable vaucheriacean chromalveolate algae from the late Mesoproterozoic, and populations of hydrodictyacean and siphonocladalean green algae of mid Neoproterozoic age. Despite this phylogenetic breadth, however, or arguments from molecular clocks, there is no convincing evidence for pre-Ediacaran metazoans or metaphytes. The conspicuously incomplete nature of the Proterozoic record makes it difficult to resolve larger-scale ecological and evolutionary patterns. Even so, both body fossils and biomarker data point to a pre-Ediacaran biosphere dominated overwhelming by prokaryotes. Contemporaneous eukaryotes appear to be limited to conspicuously shallow water environments, and exhibit fundamentally lower levels of morphological diversity and evolutionary turnover than

  4. Latent methane in fossil coals

    Energy Technology Data Exchange (ETDEWEB)

    A.D. Alexeev; E.V. Ulyanova; G.P. Starikov; N.N. Kovriga [Academy of Sciences of Ukraine, Donetsk (Ukraine). Institute for Physics of Mining Processes

    2004-07-01

    It is established experimentally using 1H NMR wide line spectroscopy that methane can exist in coals not only in open or closed porosity and fracture systems but also in solid solutions in coal substance, in particular, under methane pressure 2 MPa or higher. Methane dissolved in coal minerals reversibly modifies their lattice parameters as determined from X-ray diffraction analysis. Co-existence of these methane forms in fossil coals causes multi-step desorption kinetics. It is shown experimentally that the long-term latent methane desorption is effected mainly by closed porosity, which in turn is determined by coal rank. 21 refs., 3 figs., 2 tabs.

  5. Dinosaur fossils predict body temperatures.

    Directory of Open Access Journals (Sweden)

    James F Gillooly

    2006-07-01

    Full Text Available Perhaps the greatest mystery surrounding dinosaurs concerns whether they were endotherms, ectotherms, or some unique intermediate form. Here we present a model that yields estimates of dinosaur body temperature based on ontogenetic growth trajectories obtained from fossil bones. The model predicts that dinosaur body temperatures increased with body mass from approximately 25 degrees C at 12 kg to approximately 41 degrees C at 13,000 kg. The model also successfully predicts observed increases in body temperature with body mass for extant crocodiles. These results provide direct evidence that dinosaurs were reptiles that exhibited inertial homeothermy.

  6. THE XMM CLUSTER SURVEY: THE STELLAR MASS ASSEMBLY OF FOSSIL GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, Craig D.; Miller, Christopher J. [Department of Astronomy, University of Michigan, Ann Arbor, MI 48109 (United States); Richards, Joseph W.; Deadman, Paul-James [Center for Time Domain Informatics, University of California, Berkeley, CA 94720 (United States); Lloyd-Davies, E. J.; Kathy Romer, A.; Mehrtens, Nicola; Liddle, Andrew R. [Astronomy Centre, University of Sussex, Falmer, Brighton BN1 9QH (United Kingdom); Hoyle, Ben [Institute of Sciences of the Cosmos (ICCUB) and IEEC, Physics Department, University of Barcelona, Barcelona 08024 (Spain); Hilton, Matt [Astrophysics and Cosmology Research Unit, School of Mathematical Sciences, University of KwaZulu-Natal, Private Bag X54001, Durban 4000 (South Africa); Stott, John P.; Capozzi, Diego; Collins, Chris A. [Astrophysics Research Institute, Liverpool John Moores University, Twelve Quays House, Egerton Wharf, Birkenhead CH41 1LD (United Kingdom); Sahlen, Martin [Oskar Klein Centre for Cosmoparticle Physics, Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm (Sweden); Stanford, S. Adam [Physics Department, University of California, Davis, CA 95616 (United States); Viana, Pedro T. P., E-mail: craigha@umich.edu [Centro de Astrofisica da Universidade do Porto, Rua das Estrelas, 4150-762 Porto (Portugal)

    2012-06-10

    This paper presents both the result of a search for fossil systems (FSs) within the XMM Cluster Survey and the Sloan Digital Sky Survey and the results of a study of the stellar mass assembly and stellar populations of their fossil galaxies. In total, 17 groups and clusters are identified at z < 0.25 with large magnitude gaps between the first and fourth brightest galaxies. All the information necessary to classify these systems as fossils is provided. For both groups and clusters, the total and fractional luminosity of the brightest galaxy is positively correlated with the magnitude gap. The brightest galaxies in FSs (called fossil galaxies) have stellar populations and star formation histories which are similar to normal brightest cluster galaxies (BCGs). However, at fixed group/cluster mass, the stellar masses of the fossil galaxies are larger compared to normal BCGs, a fact that holds true over a wide range of group/cluster masses. Moreover, the fossil galaxies are found to contain a significant fraction of the total optical luminosity of the group/cluster within 0.5 R{sub 200}, as much as 85%, compared to the non-fossils, which can have as little as 10%. Our results suggest that FSs formed early and in the highest density regions of the universe and that fossil galaxies represent the end products of galaxy mergers in groups and clusters.

  7. Modeling neck mobility in fossil turtles.

    Science.gov (United States)

    Werneburg, Ingmar; Hinz, Juliane K; Gumpenberger, Michaela; Volpato, Virginie; Natchev, Nikolay; Joyce, Walter G

    2015-05-01

    Turtles have the unparalleled ability to retract their heads and necks within their shell but little is known about the evolution of this trait. Extensive analysis of neck mobility in turtles using radiographs, CT scans, and morphometry reveals that basal turtles possessed less mobility in the neck relative to their extant relatives, although the anatomical prerequisites for modern mobility were already established. Many extant turtles are able to achieve hypermobility by dislocating the central articulations, which raises cautions about reconstructing the mobility of fossil vertebrates. A 3D-model of the Late Triassic turtle Proganochelys quenstedti reveals that this early stem turtle was able to retract its head by tucking it sideways below the shell. The simple ventrolateral bend seen in this stem turtle, however, contrasts with the complex double-bend of extant turtles. The initial evolution of neck retraction therefore occurred in a near-synchrony with the origin of the turtle shell as a place to hide the unprotected neck. In this early, simplified retraction mode, the conical osteoderms on the neck provided further protection. © 2014 Wiley Periodicals, Inc.

  8. Paleoenvironmental conditions and strontium isotope stratigraphy in the Paleogene Gafsa Basin (Tunisia) deduced from geochemical analyses of phosphatic fossils

    Science.gov (United States)

    Kocsis, László; Ounis, Anouar; Chaabani, Fredj; Salah, Neili Mohamed

    2013-06-01

    Fossil shark teeth and coprolites from three major phosphorite occurrences in the Gafsa Basin (southwestern Tunisia) were investigated for their geochemical compositions to improve local stratigraphy and to better assess paleoenvironmental conditions. 87Sr/86Sr isotope ratios of shark teeth from the Early Maastrichtian El Haria Formation and from the Early Eocene Métlaoui s.s. Formation yielded Sr isotope ages of 68 ± 1 and 47.9 ± 1.3 Ma, respectively, which accord with the expected stratigraphic positions of these sediments. Conversely, shark teeth from the Paleocene-Eocene Chouabine Formation have large variation in Sr isotope ratios even within individual layers. After statistical treatment and then elimination of certain outlier samples, three age-models are proposed and discussed. The most reasonable solution includes three subsequent Sr ages of 61.8 ± 2.2 Ma, 57.2 ± 1.8 and 54.6 ± 1.6 for layer IX, layers VIII-V and layers IV-0, respectively. Three scenarios are discussed for explanation of the presence of the outliers: (1) diagenesis, (2) re-working and (3) locally controlled seawater Sr isotope ratio. The most plausible account for the higher 87Sr/86Sr ratios relative to the global ocean in some fossils is enhanced intrabasinal re-working due to low sea level. Conversely, the sample with lower 87Sr/86Sr than the global seawater may link to diagenesis or to seawater influenced by weathering of Late Cretaceous marine carbonates, which latter is supported by model calculation as well. The ɛNd values of these fossils are very similar to those reported for Paleogene and Late Cretaceous Tethyan seawater and are compatible with the above interpretations. The relatively low oxygen isotope values in shark teeth from the topmost phosphate bed of the Chouabine Formation, together with the Sr isotope results, point toward recovering better connections with the open sea. These δ18O data reflect elevated ambient temperature, which may link to the Early Eocene

  9. Fossil energy program. Summary document

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-05-01

    This program summary document presents a comprehensive overview of the research, development, and demonstration (RD and D) activities that will be performed in FY 1981 by the Assistant Secretary for Fossil Energy (ASFE), US Department of Energy (DOE). The ASFE technology programs for the fossil resources of coal, petroleum (including oil shale) and gas have been established with the goal of making substantive contributions to the nation's future supply and efficienty use of energy. On April 29, 1977, the Administration submitted to Congress the National Energy Plan (NEP) and accompanying legislative proposals designed to establish a coherent energy policy structure for the United States. Congress passed the National Energy Act (NEA) on October 15, 1978, which allows implementation of the vital parts of the NEP. The NEP was supplemented by additional energy policy statements culminating in the President's address on July 15, 1979, presenting a program to further reduce dependence on imported petroleum. The passage of the NEA-related energy programs represent specific steps by the Administration and Congress to reorganize, redirect, and clarify the role of the Federal Government in the formulation and execution of national energy policy and programs. The energy technology RD and D prog4rams carried out by ASFE are an important part of the Federal Government's effort to provide the combination and amounts of energy resources needed to ensure national security and continued economic growth.

  10. Discovery of sponge body fossils from the late Meishucunian (Cambrian) at Jinsha, Guizhou, south China

    Institute of Scientific and Technical Information of China (English)

    YANG Xinglian; ZHAO Yuanlong; WANG Yue; WANG Pingli

    2005-01-01

    Here we report discovery of a sponge body fossil Triticispongia sp. from the base of lower Cambrian Niutitang Formation at Jinsha, Guizhou. Stratigraphically, the fossil horizon is located below Ni-Mo ore layer with the Niutitang Biota above, and is equivalent to the late Meishucunian. The species is global in shape with skeletons composed of stauractins and monaxons. Triticispongia sp. reported here may be the earliest sponge body fossils of Cambrian, which provides new informationfor understanding early evolution and radiation of sponge animals.

  11. Early warning indicators for river nutrient and sediment loads in tropical seagrass beds: a benchmark from a near-pristine archipelago in Indonesia.

    Science.gov (United States)

    van Katwijk, M M; van der Welle, M E W; Lucassen, E C H E T; Vonk, J A; Christianen, M J A; Kiswara, W; al Hakim, I Inayat; Arifin, A; Bouma, T J; Roelofs, J G M; Lamers, L P M

    2011-07-01

    In remote, tropical areas human influences increase, potentially threatening pristine seagrass systems. We aim (i) to provide a bench-mark for a near-pristine seagrass system in an archipelago in East Kalimantan, by quantifying a large spectrum of abiotic and biotic properties in seagrass meadows and (ii) to identify early warning indicators for river sediment and nutrient loading, by comparing the seagrass meadow properties over a gradient with varying river influence. Abiotic properties of water column, pore water and sediment were less suitable indicators for increased sediment and nutrient loading than seagrass properties. Seagrass meadows strongly responded to higher sediment and nutrient loads and proximity to the coast by decreasing seagrass cover, standing stock, number of seagrass species, changing species composition and shifts in tissue contents. Our study confirms that nutrient loads are more important than water nutrient concentrations. We identify seagrass system variables that are suitable indicators for sediment and nutrient loading, also in rapid survey scenarios with once-only measurements.

  12. Social Perspective on Fossilization of Interlanguage

    OpenAIRE

    Ren Hulin

    2013-01-01

    The paper is to investigate the role of social factors that influence the fossilization of learners’ interlanguage. In this context, "fossilization" refers to the stopping in the acquisition of a second language (L2) short of native-like proficiency(Towell and Hawkins, 1994). The paper begins with Wolfson’s (1989) overview of social settings that influence the fossilization of learners’ interlanguage and Ellis (2005) discussion of the impact of social factors on L2 proficiency evidenced with ...

  13. Proceedings of the second US Department of Energy environmental control symposium. Volume 1. Fossil energy

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-06-01

    These proceedings document the presentations given at the Second Environmental Control Symposium. Symposium presentations highlighted environmental control activities which span the entire DOE. Volume I contains papers relating to coal preparation, oil shales, coal combustion, advanced coal utilization (fluidized bed combustion, MHD generators, OCGT, fuel cells), coal gasification, coal liquefaction, and fossil resource extraction (enhanced recovery). Separate abstracts for individual papers are prepared for inclusion in the Energy Data Base. (DMC)

  14. A new fossil weevil (Coleoptera, Curculionoidea, Belidae) from the Yixian Formation of western Liaoning, China

    Institute of Scientific and Technical Information of China (English)

    LIU Ming; REN Dong; SHIH Chungkun

    2006-01-01

    This paper reports a new genus and a new species Microprobelus liuae gen. et sp. nov. referred to the family Belidae.This fossil was collected from the Late Jurassic Yixian Formation of western Liaoning, China. Detailed description and illustration of the specimen along with a brief review of fossil belids are given. And the age of the Yixian Formation and the early diversification of the weevils are discussed.

  15. An AFM Observation on Fossil Cytoplasm

    Institute of Scientific and Technical Information of China (English)

    WANG Xin; YU Junping; FANG Xiaohong

    2008-01-01

    Fossil cytoplasm is a new research topic of interest in paleobotany. Atomic force microscope (AFM) is a new technology applied widely in physics and biology; however, it is rarely used in paleontology. Here we applied AFM for the first time to study fossil cytoplasm. The results indicate that the fossil cytoplasm is heterogeneous and full of ultrastructures, just like extant cytoplasm, and that the application of AFM, especially in combination with other techniques, can reveal the subcellular details of fossil plants with more confidence.

  16. Fluidized bed calciner apparatus

    Science.gov (United States)

    Owen, Thomas J.; Klem, Jr., Michael J.; Cash, Robert J.

    1988-01-01

    An apparatus for remotely calcining a slurry or solution feed stream of toxic or hazardous material, such as ammonium diurante slurry or uranyl nitrate solution, is disclosed. The calcining apparatus includes a vertical substantially cylindrical inner shell disposed in a vertical substantially cylindrical outer shell, in which inner shell is disposed a fluidized bed comprising the feed stream material to be calcined and spherical beads to aid in heat transfer. Extending through the outer and inner shells is a feed nozzle for delivering feed material or a cleaning chemical to the beads. Disposed in and extending across the lower portion of the inner shell and upstream of the fluidized bed is a support member for supporting the fluidized bed, the support member having uniform slots for directing uniform gas flow to the fluidized bed from a fluidizing gas orifice disposed upstream of the support member. Disposed in the lower portion of the inner shell are a plurality of internal electric resistance heaters for heating the fluidized bed. Disposed circumferentially about the outside length of the inner shell are a plurality of external heaters for heating the inner shell thereby heating the fluidized bed. Further, connected to the internal and external heaters is a means for maintaining the fluidized bed temperature to within plus or minus approximately 25.degree. C. of a predetermined bed temperature. Disposed about the external heaters is the outer shell for providing radiative heat reflection back to the inner shell.

  17. Processes of benthic foraminiferal fossil assemblage formation on the continental slope

    Energy Technology Data Exchange (ETDEWEB)

    Loubere, P. (Northern Illinois Univ., DeKalb (United States))

    1991-03-01

    Theoretical analysis of benethic foraminiferal fossil assemblage formation shows that the assemblage eventually preserved in the sediments is an integrated result of species' test production rate, microhabitat behavior, and biogeochemical processes that control the probability of species' test preservation. The biogeochemical processes that influence test preservation in slope sediments are controlled by the flux of organic carbon to the sea-bed and the botton water oxygen concentration. These variables also affect the depth of the biotic habitation zone in the sediments. Therefore, organic carbon flux and bottom water oxygen content should be reflected in benthic foraminiferal fossil assemblages for both ecologic and taphonomic reasons. An integrated study of fossil assemblage generation was conducted on the Gulf of Mexico continental slope using box cores collected along depth transects across the oxygen minimum, and using live and dead assemblage analysis combined with {sup 210}Pb measurements to quantify biotic activity in the sediments and pore water nutrient and metals analysis to quantify biogeochemical processes acting in the sediment habitation zone. The results show that the size of the habitation zone and live standing stock are influenced by organic carbon flux and oxygen supply to the sea-bed. The fossil assemblage is created progressively through the upper 10-20 cm of sediment and biologichemically driven test destruction (taphonomic process) is important in determining the assemblage that enters the geologic record.

  18. Effectiveness of bed bug monitors for detecting and trapping bed bugs in apartments.

    Science.gov (United States)

    Wang, Changlu; Tsai, Wan-Tien; Cooper, Richard; White, Jeffrey

    2011-02-01

    Bed bugs, Cimex lectularius L., are now considered a serious urban pest in the United States. Because they are small and difficult to find, there has been strong interest in developing and using monitoring tools to detect bed bugs and evaluate the results of bed bug control efforts. Several bed bug monitoring devices were developed recently, but their effectiveness is unknown. We comparatively evaluated three active monitors that contain attractants: CDC3000, NightWatch, and a home-made dry ice trap. The Climbup Insect Interceptor, a passive monitor (without attractants), was used for estimating the bed bug numbers before and after placing active monitors. The results of the Interceptors also were compared with the results of the active monitors. In occupied apartments, the relative effectiveness of the active monitors was: dry ice trap > CDC3000 > NightWatch. In lightly infested apartments, the Interceptor (operated for 7 d) trapped similar number of bed bugs as the dry ice trap (operated for 1 d) and trapped more bed bugs than CDC3000 and NightWatch (operated for 1 d). The Interceptor was also more effective than visual inspections in detecting the presence of small numbers of bed bugs. CDC3000 and the dry ice trap operated for 1 d were equally as effective as the visual inspections for detecting very low level of infestations, whereas 1-d deployment of NightWatch detected significantly lower number of infestations compared with visual inspections. NightWatch was designed to be able to operate for several consecutive nights. When operated for four nights, NightWatch trapped similar number of bed bugs as the Interceptors operated for 10 d after deployment of NightWatch. We conclude these monitors are effective tools in detecting early bed bug infestations and evaluating the results of bed bug control programs.

  19. Fossil record of Ephedra in the Lower Cretaceous (Aptian), Argentina.

    Science.gov (United States)

    Puebla, Gabriela G; Iglesias, Ari; Gómez, María A; Prámparo, Mercedes B

    2017-05-20

    Fossil plants from the Lower Cretaceous (upper Aptian) of the La Cantera Formation, Argentina, are described. The fossils studied represent a leafy shooting system with several orders of articulated and striated axes and attached leaves with unequivocal ephedroid affinity. We also found associated remains of ovulate cones with four whorls of sterile bracts, which contain two female reproductive units (FRU). Ovulate cone characters fit well within the genus Ephedra. Special characters in the ovulate cones including an outer seed envelope with two types of trichomes, allowed us to consider our remains as a new Ephedra species. Abundant dispersed ephedroid pollen obtained from the macrofossil-bearing strata also confirms the abundance of Ephedraceae in the basin. The co-occurrence of abundant fossil of Ephedra (adapted to dry habitats) associated with thermophilic cheirolepideacean conifer pollen (Classopollis) in the unit would suggest marked seasonality at the locality during the Early Cretaceous. Furthermore, the floristic association is linked to dry sensitive rocks in the entire section. The macro- and microflora from San Luis Basin are similar in composition to several Early Cretaceous floras from the Northern Gondwana floristic province, but it may represent one of the southernmost records of an arid biome in South America.

  20. The hominin fossil record: taxa, grades and clades.

    Science.gov (United States)

    Wood, Bernard; Lonergan, Nicholas

    2008-04-01

    This paper begins by reviewing the fossil evidence for human evolution. It presents summaries of each of the taxa recognized in a relatively speciose hominin taxonomy. These taxa are grouped in grades, namely possible and probable hominins, archaic hominins, megadont archaic hominins, transitional hominins, pre-modern Homo and anatomically modern Homo. The second part of this contribution considers some of the controversies that surround hominin taxonomy and systematics. The first is the vexed question of how you tell an early hominin from an early panin, or from taxa belonging to an extinct clade closely related to the Pan-Homo clade. Secondly, we consider how many species should be recognized within the hominin fossil record, and review the philosophies and methods used to identify taxa within the hominin fossil record. Thirdly, we examine how relationships within the hominin clade are investigated, including descriptions of the methods used to break down an integrated structure into tractable analytical units, and then how cladograms are generated and compared. We then review the internal structure of the hominin clade, including the problem of how many subclades should be recognized within the hominin clade, and we examine the reliability of hominin cladistic hypotheses. The last part of the paper reviews the concepts of a genus, including the criteria that should be used for recognizing genera within the hominin clade.

  1. Paleoradiology. Imaging mummies and fossils

    Energy Technology Data Exchange (ETDEWEB)

    Chhem, Rethy K. [Western Ontario Univ. London Health Sciences Centre, ON (Canada). Dept. of Diagnostic Radiology and Nuclear Medicine; Brothwell, Don R. [York Univ. (United Kingdom). Dept. of Archaeology

    2008-07-01

    This is an important work on a topic of huge interest to archaeologists and related scientists, since the use of imaging techniques in the field has been expanding rapidly in recent decades. Paleoradiology involves the use of X-rays and advanced medical imaging modalities to evaluate ancient human and animal skeletons as well as biological materials from archaeological sites. Paleoradiological studies have been performed on mummies, skeletal remains and fossils to determine their sex and age at death. Diagnostic paleoradiology is the use of X-ray studies to detect ancient diseases. The broad range of themes and imaging techniques in this volume reflects four decades of research undertaken by Don Brothwell in the fields of anthropology, human paleopathology, and zooarchaeology, combined with two decades of skeletal radiology experience during which Rethy Chhem read over 150,000 skeletal X-ray and CT studies. (orig.)

  2. What fossils can tell us about the evolution of viviparity and placentation

    DEFF Research Database (Denmark)

    Carter, A M

    2008-01-01

    mammals is reviewed. Of particular interest are the fossils of horses as they document that a reproductive strategy with a single precocial newborn was evolved early on. In one instance there is sufficient representation of soft tissue to imply that early horses had a diffuse placenta, much as had been...

  3. A high resolution stratigraphic framework for the remarkable fossil cetacean assemblage of the Miocene/Pliocene Pisco Formation, Peru

    Science.gov (United States)

    Brand, Leonard; Urbina, Mario; Chadwick, Arthur; DeVries, Thomas J.; Esperante, Raul

    2011-04-01

    The Miocene/Pliocene Pisco Formation of Peru contains a rich marine vertebrate fossil record, providing a unique opportunity for the study of paleoecology and evolution, along with the sedimentological context of the fossils. The lack of a high-resolution stratigraphic framework has hampered such study. In this paper we develop the needed stratigraphy for the areas in the Pisco Formation where most of the vertebrate paleontological research is occurring. In the Ica Valley and in the vicinity of Lomas, series of lithologically or paleontologically unique marker beds were identified. These were walked out and documented with GPS technology. Measured sections connecting these marker beds provide a stratigraphic framework for the areas studied. GPS locations, maps of the marker beds on aerial photographs, and outcrop photographs allow field determination of the stratigraphic positions of study areas.

  4. Fossil mammals and paleoenvironments in the Omo-Turkana Basin.

    Science.gov (United States)

    Bobe, René

    2011-01-01

    Although best known for its fossil hominins, the Omo-Turkana Basin of Kenya and Ethiopia is the source of one of the best records of vertebrate evolution from the Late Cenozoic of Africa. Located near the heart of the East African Rift Valley, the basin serves as an important frame of reference for the continent. The fossil record from this region plays a key role in our efforts to understand the environmental and ecological context of human evolution in Africa. The Omo-Turkana faunal data shed light on key questions of human evolution: What kinds of environments did early humans inhabit? How did these environments change over time? What is the relationship between faunal change in East Africa and broader patterns of climatic change? Copyright © 2011 Wiley Periodicals, Inc.

  5. Molecular and Fossil Evidence on the Origin of Angiosperms

    Science.gov (United States)

    Doyle, James A.

    2012-05-01

    Molecular data on relationships within angiosperms confirm the view that their increasing morphological diversity through the Cretaceous reflected their evolutionary radiation. Despite the early appearance of aquatics and groups with simple flowers, the record is consistent with inferences from molecular trees that the first angiosperms were woody plants with pinnately veined leaves, multiparted flowers, uniovulate ascidiate carpels, and columellar monosulcate pollen. Molecular data appear to refute the hypothesis based on morphology that angiosperms and Gnetales are closest living relatives. Morphological analyses of living and fossil seed plants that assume molecular relationships identify glossopterids, Bennettitales, and Caytonia as angiosperm relatives; these results are consistent with proposed homologies between the cupule of glossopterids and Caytonia and the angiosperm bitegmic ovule. Jurassic molecular dates for the angiosperms may be reconciled with the fossil record if the first angiosperms were restricted to wet forest understory habitats and did not radiate until the Cretaceous.

  6. Fossil bacteria in Xuanlong iron ore deposits of Hebei Province

    Institute of Scientific and Technical Information of China (English)

    DAI Yongding; SONG Haiming; SHEN Jiying

    2004-01-01

    Discovered in Early Proterozoic Xuanlong iron ore deposits are six genera of fossil iron bacteria, i. e. sphere (coenobium of) rod-shaped (monomer) Naumanniella, ellipsoid elliptical Ochrobium, sphere spherical Siderocapsa and chain spherical Siderococcus, chain rod-shaped Leptothrix and Lieskeella, and six genera of fossil blue bacteria, namely sphere spherical Gloeocapsa, Synechocystis and Globobacter, chain spherical Anabaena and Nostoc, and constrictive septate tubular Nodularia. The biomineralized monomers and coenobia of the two categories of bacteria, together with hematite plates made up the bacteria pelletal, bacteria silky,bacteria fibrous and clasty bacteria pelletal textural lamina. The bacteria pelletal laminae combined with other bacteria laminae to make up oncolite, stromatolite and laminate. The precipitation of iron oxide was accelerated due to iron and blue bacteria cohabiting on microbial film or mat. The Xuanlong iron ore deposits are microbial binding ore deposits of ocean source.

  7. Phase 2 Trial of Accelerated, Hypofractionated Whole-Breast Irradiation of 39 Gy in 13 Fractions Followed by a Tumor Bed Boost Sequentially Delivering 9 Gy in 3 Fractions in Early-Stage Breast Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ja Young [Proton Therapy Center, Research Institute and Hospital, National Cancer Center, Goyang (Korea, Republic of); Jung, So-Youn; Lee, Seeyoun; Kang, Han-Sung; Lee, Eun Sook; Park, In Hae; Lee, Keun Seok; Ro, Jungsil [Center for Breast Cancer, Research Institute and Hospital, National Cancer Center, Goyang (Korea, Republic of); Lee, Nam Kwon [Proton Therapy Center, Research Institute and Hospital, National Cancer Center, Goyang (Korea, Republic of); Department of Radiation Oncology, Korea University Medical Center, Collage of Medicine, Seoul (Korea, Republic of); Shin, Kyung Hwan, E-mail: radiat@ncc.re.kr [Proton Therapy Center, Research Institute and Hospital, National Cancer Center, Goyang (Korea, Republic of); Department of Radiation Oncology, Korea University Medical Center, Collage of Medicine, Seoul (Korea, Republic of)

    2013-12-01

    Purpose: To report a phase 2 trial of accelerated, hypofractionated whole-breast irradiation (AH-WBI) delivered as a daily dose of 3 Gy to the whole breast followed by a tumor bed boost. Methods and Materials: Two hundred seventy-six patients diagnosed with breast cancer (pT1-2 and pN0-1a) who had undergone breast-conserving surgery in which the operative margins were negative were treated with AH-WBI delivered as 39 Gy in 13 fractions of 3 Gy to the whole breast once daily over 5 consecutive working days, and 9 Gy in 3 sequential fractions of 3 Gy to a lumpectomy cavity, all within 3.2 weeks. Results: After a median follow-up period of 57 months (range: 27-75 months), the rate of 5-year locoregional recurrence was 1.4% (n=4), whereas that of disease-free survival was 97.4%. No grade 3 skin toxicity was reported during the follow-up period. Qualitative physician cosmetic assessments of good or excellent were noted in 82% of the patients at 2 months after the completion of AH-WBI. The global cosmetic outcome did not worsen over time, and a good or excellent cosmetic outcome was reported in 82% of the patients at 3 years. The mean pretreatment percentage breast retraction assessment was 12.00 (95% confidence interval [CI]: 11.14-12.86). The mean value of percentage breast retraction assessment increased to 13.99 (95% CI: 12.17-15.96) after 1 year and decreased to 13.54 (95% CI: 11.84-15.46) after 3 years but was not significant (P>.05). Conclusions: AH-WBI consisting of 39 Gy in 13 fractions followed by a tumor bed boost sequentially delivering 9 Gy in 3 fractions can be delivered with excellent disease control and tolerable skin toxicity in patients with early-stage breast cancer after breast-conserving surgery.

  8. The non-uniformity of fossil preservation.

    Science.gov (United States)

    Holland, Steven M

    2016-07-19

    The fossil record provides the primary source of data for calibrating the origin of clades. Although minimum ages of clades are given by the oldest preserved fossil, these underestimate the true age, which must be bracketed by probabilistic methods based on multiple fossil occurrences. Although most of these methods assume uniform preservation rates, this assumption is unsupported over geological timescales. On geologically long timescales (more than 10 Myr), the origin and cessation of sedimentary basins, and long-term variations in tectonic subsidence, eustatic sea level and sedimentation rate control the availability of depositional facies that preserve the environments in which species lived. The loss of doomed sediments, those with a low probability of preservation, imparts a secular trend to fossil preservation. As a result, the fossil record is spatially and temporally non-uniform. Models of fossil preservation should reflect this non-uniformity by using empirical estimates of fossil preservation that are spatially and temporally partitioned, or by using indirect proxies of fossil preservation. Geologically, realistic models of preservation will provide substantially more reliable estimates of the origination of clades.This article is part of the themed issue 'Dating species divergences using rocks and clocks'.

  9. Estimating body mass of fossil rodents

    NARCIS (Netherlands)

    Freudenthal, M.; Martín-Suárez, E.

    2013-01-01

    Reconstructing the body mass of a fossil animal is an essential step toward understanding its palaeoecological role. Length × width (L×W) of the first lower molar (m1) is frequently used as a proxy for body mass in fossil mammals. However, among rodents, Muroidea have no premolar and an elongated m1

  10. Fossil evidence of the zygomycetous fungi

    NARCIS (Netherlands)

    Krings, M.; Taylor, T.N.; Dotzler, N.

    2013-01-01

    Molecular clock data indicate that the first zygomycetous fungi occurred on Earth during the Precambrian, however, fossil evidence of these organisms has been slow to accumulate. In this paper, the fossil record of the zygomycetous fungi is compiled, with a focus on structurally preserved Carbonifer

  11. A new Lower Triassic ichthyopterygian assemblage from Fossil Hill, Nevada

    Directory of Open Access Journals (Sweden)

    Neil P. Kelley

    2016-01-01

    Full Text Available We report a new ichthyopterygian assemblage from Lower Triassic horizons of the Prida Formation at Fossil Hill in central Nevada. Although fragmentary, the specimens collected so far document a diverse fauna. One partial jaw exhibits isodont dentition with blunt tipped, mesiodistally compressed crowns and striated enamel. These features are shared with the Early Triassic genus Utatsusaurus known from coeval deposits in Japan and British Columbia. An additional specimen exhibits a different dentition characterized by relatively small, rounded posterior teeth resembling other Early Triassic ichthyopterygians, particularly Grippia. This Nevada assemblage marks a southward latitudinal extension for Early Triassic ichthyopterygians along the eastern margin of Panthalassa and indicates repeated trans-hemispheric dispersal events in Early Triassic ichthyopterygians.

  12. Radio properties of fossil galaxy groups

    Science.gov (United States)

    Miraghaei, H.; Khosroshahi, H. G.

    2016-09-01

    We study 1.4 GHz radio properties of a sample of fossil galaxy groups using GMRT radio observations and the FIRST survey catalog. Fossil galaxy groups, having no recent major mergers in their dominant galaxies and also group scale mergers, give us the opportunity to investigate the effect of galaxy merger on AGN activity. In this work, we compare the radio properties of a rich sample of fossil groups with a sample of normal galaxy groups and clusters and show that the brightest group galaxies in fossil groups are under luminous at 1.4 GHz, relative to the general population of the brightest group galaxies, indicating that the dynamically relaxed nature of fossil groups has influenced the AGN activity in their dominant galaxy.

  13. A preliminary study of the effects of plastic film-mulched raised beds on soil temperature and crop performance of early-sown short-season spring maize (Zea mays L. in the North China Plain

    Directory of Open Access Journals (Sweden)

    Jing Dang

    2016-08-01

    Full Text Available To identify a strategy for earlier sowing and harvesting of spring maize (Zea mays L. in an alternative maize–maize double cropping system, a 2-year field experiment was performed at Quzhou experimental station of China Agricultural University in 2014 and 2015. A short-season cultivar, Demeiya number 1 (KX7349, was used in the experiment. Soil temperature to 5 cm depth in the early crop growth stage, crop growth, crop yield, and water use of different treatments (plastic film-mulched raised bed (RF and flat field without plastic film mulching (CK in 2014; RF, plastic film-mulched flat field (FF, and CK in 2015 were measured or calculated and compared. Soil temperature in the film-mulched treatments was consistently higher than that in CK (1.6–3.5 °C in average during the early growth stage. Crops in plastic film-mulched treatments used 214 fewer growing-degree days (GDDs in 2014 and 262 fewer GDDs in 2015. In 2014, the RF treatment yielded 32.7% higher biomass than CK, although its 9.4% higher grain yield was not statistically significant. Also, RF used 17.9% less water and showed 33.1% higher water use efficiency (WUE than CK. In 2015, RF and FF showed 56.2% and 49.5% higher yield, 15.0% and 4.5% lower water use (ET, and 63.4% and 75.7% higher WUE, respectively, than CK. RF markedly increased soil temperature in the early crop season, accelerated crop growth, reduced ET, and greatly increased crop yield and WUE. Compared with FF, RF had no obvious effect on crop growth rate, although soil temperature during the period between sowing and stem elongation was slightly increased. However, RF resulted in lower ET and higher WUE than FF. Effects of RF on soil water dynamics as well as its cost-effectiveness remain topics for further study.

  14. New dinosaur fossils from ANA locality, Arcillas de Morella Formation (Aptian, Lower Cretaceous, Cinctorres, Spain)

    Science.gov (United States)

    Santos-Cubedo, A.; de Santisteban, C.; Suñer, M.; Galobart, A.

    2009-04-01

    Ana is one of the several dinosaur bone sites located in the Arcillas de Morella Formation (Aptian, Lower Cretaceous; eastern Iberian Chain, Spain). This site was discovered in 1998, but it remained unexcavated until 2002, when a palaeontologist team formed by members of the Institut Paleontología Miquel Crusafont from Sabadell and the Grup Guix from Vila-real unearthed the first fossil from the locality. Nowadays there are five hundred fossils collected, including vertebrate and invertebrate species. Dinosaur bones (Theropoda and Ornithopoda) are abundant in this assemblage and in the last field season bones determined as Sauropoda were found. Taxonomically, Ana is dominated by disarticulated remains of Ornithopoda, which are usually fragmentary and abraded. Many of the elements may have been reworked (spatial averaging and/or time averaging), and the fossil concentration constitutes an autochthonous to parautochthonous association, in a spatial sense. The remains found in the Ana fossils site are placed in sandstones and limes containing marine autochthonous fauna. These deposits were formed during the transgressive infilling of an incised valley. Sedimentological features indicate that fossils were finally deposited in starved shallow estuarine environment. Mineralogically, the sediment including the fossils contains grains of quartz, illite/mica, kaolinite/clorite, K-feldspar and plagioclase, distributed in two mainly grain populations, a silty-clay and a coarse sand size grain, indicating that the sediments were bedded in a low-medium energy depositional environment. Nowadays we identified in Ana, teeth of Theropoda indet. and Baryonychinae indet., and bones of Iguanodon sp. Herein, we report new fossil findings from Ana site. These materials have been determined as Iguanodontia, Titanosauriformes and Theropoda. These new findings will help to understand the dinosaur fauna present in the Lower Cretaceous of Els Ports (Castellón, Spain). Acknowledgments This

  15. Tapered bed bioreactor

    Science.gov (United States)

    Scott, Charles D.; Hancher, Charles W.

    1977-01-01

    A vertically oriented conically shaped column is used as a fluidized bed bioreactor wherein biologically catalyzed reactions are conducted in a continuous manner. The column utilizes a packing material a support having attached thereto a biologically active catalytic material.

  16. Bed Bugs FAQs

    Science.gov (United States)

    ... Bed bugs have been found in five-star hotels and resorts and their presence is not determined ... sleep. These areas include apartments, shelters, rooming houses, hotels, cruise ships, buses, trains, and dorm rooms. They ...

  17. Moving-bed sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Ayala, R.E.; Gupta, R.P.; Chuck, T.

    1995-12-01

    The objective of this program is to develop mixed-metal oxide sorbent formulations that are suitable for moving-bed, high-temperature, desulfurization of coal gas. Work continues on zinc titanates formulations and Z-sorb III sorbent.

  18. Bed Bug Information Clearinghouse

    Science.gov (United States)

    Its purpose is to help states, communities, and consumers in efforts to prevent and control bed bug infestations. Currently includes only reviewed material from federal/state/local government agencies, extension services, and universities.

  19. Bed Bug Tips

    Science.gov (United States)

    How to deal with bed bugs in one printable page. Ten tips include ensuring correct insect identification, reducing clutter, understand integrated pest management, using mattress and box spring encasements, and heat treatment.

  20. The controversial "Cambrian" fossils of the Vindhyan are real but more than a billion years older.

    Science.gov (United States)

    Bengtson, Stefan; Belivanova, Veneta; Rasmussen, Birger; Whitehouse, Martin

    2009-05-12

    The age of the Vindhyan sedimentary basin in central India is controversial, because geochronology indicating early Proterozoic ages clashes with reports of Cambrian fossils. We present here an integrated paleontologic-geochronologic investigation to resolve this conundrum. New sampling of Lower Vindhyan phosphoritic stromatolitic dolomites from the northern flank of the Vindhyans confirms the presence of fossils most closely resembling those found elsewhere in Cambrian deposits: annulated tubes, embryo-like globules with polygonal surface pattern, and filamentous and coccoidal microbial fabrics similar to Girvanella and Renalcis. None of the fossils, however, can be ascribed to uniquely Cambrian or Ediacaran taxa. Indeed, the embryo-like globules are not interpreted as fossils at all but as former gas bubbles trapped in mucus-rich cyanobacterial mats. Direct dating of the same fossiliferous phosphorite yielded a Pb-Pb isochron of 1,650 +/- 89 (2sigma) million years ago, confirming the Paleoproterozoic age of the fossils. New U-Pb geochronology of zircons from tuffaceous mudrocks in the Lower Vindhyan Porcellanite Formation on the southern flank of the Vindhyans give comparable ages. The Vindhyan phosphorites provide a window of 3-dimensionally preserved Paleoproterozoic fossils resembling filamentous and coccoidal cyanobacteria and filamentous eukaryotic algae, as well as problematic forms. Like Neoproterozoic phosphorites a billion years later, the Vindhyan deposits offer important new insights into the nature and diversity of life, and in particular, the early evolution of multicellular eukaryotes.

  1. Discovery of fossil lamprey larva from the Lower Cretaceous reveals its three-phased life cycle.

    Science.gov (United States)

    Chang, Mee-mann; Wu, Feixiang; Miao, Desui; Zhang, Jiangyong

    2014-10-28

    Lampreys are one of the two surviving jawless vertebrate groups and one of a few vertebrate groups with the best exemplified metamorphosis during their life cycle, which consists of a long-lasting larval stage, a peculiar metamorphosis, and a relatively short adulthood with a markedly different anatomy. Although the fossil records have revealed that many general features of extant lamprey adults were already formed by the Late Devonian (ca. 360 Ma), little is known about the life cycle of the fossil lampreys because of the lack of fossilized lamprey larvae or transformers. Here we report the first to our knowledge discovery of exceptionally preserved premetamorphic and metamorphosing larvae of the fossil lamprey Mesomyzon mengae from the Lower Cretaceous of Inner Mongolia, China. These fossil ammocoetes look surprisingly modern in having an eel-like body with tiny eyes, oral hood and lower lip, anteriorly positioned branchial region, and a continuous dorsal skin fin fold and in sharing a similar feeding habit, as judged from the detritus left in the gut. In contrast, the larger metamorphosing individuals have slightly enlarged eyes relative to large otic capsules, thickened oral hood or pointed snout, and discernable radials but still anteriorly extended branchial area and lack a suctorial oral disk, which characterize the early stages of the metamorphosis of extant lampreys. Our discovery not only documents the larval conditions of fossil lampreys but also indicates the three-phased life cycle in lampreys emerged essentially in their present mode no later than the Early Cretaceous.

  2. Approaches to bioremediation of fossil fuel contaminated soil: An ...

    African Journals Online (AJOL)

    Biological methods for combating pollutants generated within the fossil fuels ... metabolism of fossil fuel contaminants in soil and water bodies is presented. ... Keywords: Fossil fuels, coal, petroleum hydrocarbons, biodegradation, pollutants

  3. Fossilization in Geopark Araripe studied through X-ray diffraction, scanning microscopy and thermogravimetric analysis

    CERN Document Server

    Lima, Ricardo J C; Macedo, Zélia S; Sasaki, José M; Saraiva, Antônio A F

    2008-01-01

    The Geopark Araripe, located in Northeastern Brazil, is the first UNESCO Natural Park in the South hemisphere and a world-famous fossil deposit of the Early Cretaceous period (approximately 120 million years). Fossilized fish fauna in Geopark Araripe is found inside of sedimentary rocks in three-dimensional forms. In the present study sedimentary rocks and fossil fish Rhacolepis bucalis have been carefully analysed by means of X-ray powder diffraction, scanning electron microscopy and termogravimetric analysis. Mineralogical composition of the fossil fish was explained in terms of facts occurred at the initial stages of the opening of the South Atlantic and the oceanic hydrothermal phenomena (``black smoker'', ``white smoker'' and warm-water events). The occurrence of organic substance was, for the first time, evaluated in collapsed internal elements (intestinal and muscles) by termogravimetric analysis.

  4. Discovery of phosphatized gastrula fossils from the Doushantuo Formation, Weng'an,Guizhou Province, China

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Globular fossils from Doushantuo phosphorites at the Weng'an area are for the first time identified as a gastrulation stage of phosphatized embryos. They are got from the fossiliferous remains after acetic acid maceration. The fossils are found together with formerly reported animal resting eggs and embryos of the earlier cleavage stage. The oblate-shaped fossils with the same size as those reported embryos and invaginate at the middle part into the embryos, show the characteristics of the late blastula to the early gastrula stage of the embryo development. This discovery convinces the existence of animal embryos at Doushantuo age and offers new facts for the studying of the affinity of related fossils, which are still controversial at present.

  5. The nature of fossil bacteria: A guide to the search for extraterrestrial life

    Science.gov (United States)

    Westall, Frances

    1999-07-01

    In an attempt to establish reliable criteria for the identification of potential fossil life in extraterrestrial materials, the fossilizable characteristics of bacteria, namely, size, shape, cell wall texture, association, and colony formation, are described, and an overview is given of the ways in which fossil bacteria are preserved (as compressions in fine-grained sediments; preservation in amber; permineralized by silica; replacement by minerals such as silica, pyrite, Fe/Mn oxides, calcite, phosphate, and siderite; or as molds in minerals). The problem of confounding minerally replaced bacteria with non biological structures having a bacterial morphology is addressed. Examples of fossilized bacteria from the Early Archaean through to the Recent are used to illustrate the various modes of preservation and the morphology of fossil bacteria.

  6. Fossil fungi with suggested affinities to the Endogonaceae from the Middle Triassic of Antarctica.

    Science.gov (United States)

    Krings, Michael; Taylor, Thomas N; Dotzler, Nora; Persichini, Gianna

    2012-01-01

    Documented fossil evidence of zygomycetous fungi is rare. A conspicuous fungal fossil, Jimwhitea circumtecta gen. et sp. nov., occurs in permineralized peat from the Middle Triassic of Antarctica. The fossil is interpreted as a mantled zygosporangium that buds from a macrogametangium subtended by a sac-like macrosuspensor. The macrogametangium is united at its tip with a microgametangium which is subtended by a micro-suspensor. This configuration is strikingly similar to the zygosporangium-gametangia complexes seen in certain modern Endogonaceae. Co-occurring with J. circumtecta are isolated propagules closely resembling the zygosporangium of J. circumtecta and a portion of a sporocarp containing zygosporangia embedded in a gleba. Several of the sporangia are borne on ovoid or elongate structures, which we interpret as gametangia. These fossils offer an exceptionally detailed view of the morphology and reproductive biology of early Mesozoic zygomycetes.

  7. Summary statistics for fossil spider species taxonomy

    Directory of Open Access Journals (Sweden)

    David Penney

    2012-05-01

    Full Text Available Spiders (Araneae are one of the most species-rich orders on Earth today, and also have one of the longest geological records of any terrestrial animal groups, as demonstrated by their extensive fossil record. There are currently around 1150 described fossil spider species, representing 2.6% of all described spiders (i.e. extinct and extant. Data for numbers of fossil and living spider taxa described annually (and various other metrics for the fossil taxa were compiled from current taxonomic catalogues. Data for extant taxa showed a steady linear increase of approximately 500 new species per year over the last decade, reflecting a rather constant research activity in this area by a large number of scientists, which can be expected to continue. The results for fossil species were very different, with peaks of new species descriptions followed by long troughs, indicating minimal new published research activity for most years. This pattern is indicative of short bursts of research by a limited number of authors. Given the frequent discovery of new fossil deposits containing spiders, a wealth of new material coming to light from previously worked deposits, and the application of new imaging techniques in palaeoarachnology that allow us to extract additional data from historical specimens, e.g. X-ray computed tomography, it is important not only to ensure a sustained research activity on fossil spiders (and other arachnids through training and enthusing the next generation of palaeoarachnologists, but preferably to promote increased research and expertise in this field.

  8. Shock-Induced Flows through Packed Beds: Transient Regimes

    CERN Document Server

    Shtemler, Yuri M; Britan, Alex

    2006-01-01

    The early stage of the transient regimes in the shock-induced flows within solid-packed beds are investigated in the linear longwave and high-frequency approximation. The transient resistance law is refined as the Duhameltime integral that follows from the general concept of dynamic tortuosity and compressibility of the packed beds. A closed-form solution is expected to describe accurately the early stage of the transient regime flow and is in qualitative agreement with available experimental data.

  9. Five-year results of a prospective case series of accelerated hypofractionated whole breast radiation with concomitant boost to the surgical bed after conserving surgery for early breast cancer.

    Science.gov (United States)

    Cante, Domenico; Franco, Pierfrancesco; Sciacero, Piera; Girelli, Giuseppe; Marra, Anna Maria; Pasquino, Massimo; Russo, Giuliana; Borca, Valeria Casanova; Mondini, Guido; Paino, Ovidio; Barmasse, Roberto; Tofani, Santi; Numico, Gianmauro; La Porta, Maria Rosa; Ricardi, Umberto

    2013-06-01

    Accelerated hypofractionation (HF) using larger dose per fraction, delivered in fewer fractions over a shorter overall treatment time, is presently a consistent possibility for adjuvant whole breast radiation (WBRT) after breast-conserving surgery for early breast cancer (EBC). Between 2005 and 2008, we submitted 375 consecutive patients to accelerated hypofractionated WBRT after breast-conserving surgery for EBC. The basic course of radiation consisted of 45 Gy in 20 fractions over 4 weeks to the whole breast (2.25 Gy daily) with an additional daily concomitant boost of 0.25 Gy up to 50 Gy to the surgical bed. Overall survival (OS), cancer-specific survival (CSS), disease-free survival (DFS) and local control (LC) were assessed. Late toxicity was scored according to the CTCAE v3.0; acute toxicity using the RTOG/EORTC toxicity scale. Cosmesis was assessed comparing treated and untreated breast. Quality of life (QoL) was determined using EORTC QLQ-C30/QLQ-BR23 questionnaires. With a median follow-up of 60 months (range 42-88), 5 years OS, CSS, DFS and LC were 97.6, 99.4, 96.6 and 100 %, respectively. Late skin and subcutaneous toxicity was generally mild, with few events > grade 2 observed. Cosmetic results were excellent in 75.7 % of patients, good in 20 % and fair in 4.3 %. QoL, assessed both through QLQ-C30/QLQ-BR23, was generally favorable, within the functioning and symptoms domains. Our study is another proof of principle that HF WBRT with a concurrent boost dose to the surgical cavity represents a safe and effective postoperative treatment modality with excellent local control and survival, consistent cosmetic results and mild toxicity.

  10. Spherule Beds 3.47-3.24 Billion Years Old in the Barberton Greenstone Belt, South Africa: A Record of Large Meteorite Impacts and Their Influence on Early Crustal and Biological Evolution

    Science.gov (United States)

    Lowe, Donald R.; Byerly, Gary R.; Kyte, Frank T.; Shukolyukov, Alexander; Asaro, Frank; Krull, Alexander

    2003-01-01

    Four layers, S1-S4, containing sand-sized spherical particles formed as a result of large meteorite impacts, occur in 3.47-3.24 Ga rocks of the Barberton Greenstone Belt, South Africa. Ir levels in S3 and S4 locally equal or exceed chondritic values but in other sections are at or only slightly above background. Most spherules are inferred to have formed by condensation of impact-produced rock vapor clouds, although some may represent ballistically ejected liquid droplets. Extreme Ir abundances and heterogeneity may reflect element fractionation during spherule formation, hydraulic fractionation during deposition, and/or diagenetic and metasomatic processes. Deposition of S1, S2, and S3 was widely influenced by waves and/or currents interpreted to represent impact-generated tsunamis, and S1 and S2 show multiple graded layers indicating the passage of two or more wave trains. These tsunamis may have promoted mixing within a globally stratified ocean, enriching surface waters in nutrients for biological communities. S2 and S3 mark the transition from the 300-million-year-long Onverwacht stage of predominantly basaltic and komatiitic volcanism to the late orogenic stage of greenstone belt evolution, suggesting that regional and possibly global tectonic reorganization resulted from these large impacts. These beds provide the oldest known direct record of terrestrial impacts and an opportunity to explore their influence on early life, crust, ocean, and atmosphere. The apparent presence of impact clusters at 3.26-3.24 Ga and approx. 2.65-2.5 Ga suggests either spikes in impact rates during the Archean or that the entire Archean was characterized by terrestrial impact rates above those currently estimated from the lunar cratering record.

  11. Spherule Beds 3.47-3.24 Billion Years Old in the Barberton Greenstone Belt, South Africa: A Record of Large Meteorite Impacts and Their Influence on Early Crustal and Biological Evolution

    Science.gov (United States)

    Lowe, Donald R.; Byerly, Gary R.; Kyte, Frank T.; Shukolyukov, Alexander; Asaro, Frank; Krull, Alexander

    2003-01-01

    Four layers, S1-S4, containing sand-sized spherical particles formed as a result of large meteorite impacts, occur in 3.47-3.24 Ga rocks of the Barberton Greenstone Belt, South Africa. Ir levels in S3 and S4 locally equal or exceed chondritic values but in other sections are at or only slightly above background. Most spherules are inferred to have formed by condensation of impact-produced rock vapor clouds, although some may represent ballistically ejected liquid droplets. Extreme Ir abundances and heterogeneity may reflect element fractionation during spherule formation, hydraulic fractionation during deposition, and/or diagenetic and metasomatic processes. Deposition of S1, S2, and S3 was widely influenced by waves and/or currents interpreted to represent impact-generated tsunamis, and S1 and S2 show multiple graded layers indicating the passage of two or more wave trains. These tsunamis may have promoted mixing within a globally stratified ocean, enriching surface waters in nutrients for biological communities. S2 and S3 mark the transition from the 300-million-year-long Onverwacht stage of predominantly basaltic and komatiitic volcanism to the late orogenic stage of greenstone belt evolution, suggesting that regional and possibly global tectonic reorganization resulted from these large impacts. These beds provide the oldest known direct record of terrestrial impacts and an opportunity to explore their influence on early life, crust, ocean, and atmosphere. The apparent presence of impact clusters at 3.26-3.24 Ga and approx. 2.65-2.5 Ga suggests either spikes in impact rates during the Archean or that the entire Archean was characterized by terrestrial impact rates above those currently estimated from the lunar cratering record.

  12. Bayesian phylogenetic estimation of fossil ages

    Science.gov (United States)

    Drummond, Alexei J.; Stadler, Tanja

    2016-01-01

    Recent advances have allowed for both morphological fossil evidence and molecular sequences to be integrated into a single combined inference of divergence dates under the rule of Bayesian probability. In particular, the fossilized birth–death tree prior and the Lewis-Mk model of discrete morphological evolution allow for the estimation of both divergence times and phylogenetic relationships between fossil and extant taxa. We exploit this statistical framework to investigate the internal consistency of these models by producing phylogenetic estimates of the age of each fossil in turn, within two rich and well-characterized datasets of fossil and extant species (penguins and canids). We find that the estimation accuracy of fossil ages is generally high with credible intervals seldom excluding the true age and median relative error in the two datasets of 5.7% and 13.2%, respectively. The median relative standard error (RSD) was 9.2% and 7.2%, respectively, suggesting good precision, although with some outliers. In fact, in the two datasets we analyse, the phylogenetic estimate of fossil age is on average less than 2 Myr from the mid-point age of the geological strata from which it was excavated. The high level of internal consistency found in our analyses suggests that the Bayesian statistical model employed is an adequate fit for both the geological and morphological data, and provides evidence from real data that the framework used can accurately model the evolution of discrete morphological traits coded from fossil and extant taxa. We anticipate that this approach will have diverse applications beyond divergence time dating, including dating fossils that are temporally unconstrained, testing of the ‘morphological clock', and for uncovering potential model misspecification and/or data errors when controversial phylogenetic hypotheses are obtained based on combined divergence dating analyses. This article is part of the themed issue ‘Dating species divergences

  13. Fossil fuel support mechanisms in Finland

    Energy Technology Data Exchange (ETDEWEB)

    Lampinen, Ari

    2013-10-15

    Fossil fuel subsidies and other state support for fossil fuels are forbidden by the Kyoto Protocol and other international treaties. However, they are still commonly used. This publication presents and analyses diverse state support mechanisms for fossil fuels in Finland in 2003-2010. Total of 38 support mechanisms are covered in quantitative analysis and some other mechanisms are mentioned qualitatively only. For some mechanisms the study includes a longer historical perspective. This is the case for tax subsidies for crude oil based traffic fuels that have been maintained in Finland since 1965.

  14. Fossils, molecules and embryos: new perspectives on the Cambrian explosion

    Science.gov (United States)

    Valentine, J. W.; Jablonski, D.; Erwin, D. H.

    1999-01-01

    The Cambrian explosion is named for the geologically sudden appearance of numerous metazoan body plans (many of living phyla) between about 530 and 520 million years ago, only 1.7% of the duration of the fossil record of animals. Earlier indications of metazoans are found in the Neoproterozic; minute trails suggesting bilaterian activity date from about 600 million years ago. Larger and more elaborate fossil burrows appear near 543 million years ago, the beginning of the Cambrian Period. Evidence of metazoan activity in both trace and body fossils then increased during the 13 million years leading to the explosion. All living phyla may have originated by the end of the explosion. Molecular divergences among lineages leading to phyla record speciation events that have been earlier than the origins of the new body plans, which can arise many tens of millions of years after an initial branching. Various attempts to date those branchings by using molecular clocks have disagreed widely. While the timing of the evolution of the developmental systems of living metazoan body plans is still uncertain, the distribution of Hox and other developmental control genes among metazoans indicates that an extensive patterning system was in place prior to the Cambrian. However, it is likely that much genomic repatterning occurred during the Early Cambrian, involving both key control genes and regulators within their downstream cascades, as novel body plans evolved.

  15. At the origin of animals: the revolutionary cambrian fossil record.

    Science.gov (United States)

    Budd, Graham E

    2013-09-01

    The certain fossil record of animals begins around 540 million years ago, close to the base of the Cambrian Period. A series of extraordinary discoveries starting over 100 years ago with Walcott's discovery of the Burgess Shale has accelerated in the last thirty years or so with the description of exceptionally-preserved Cambrian fossils from around the world. Such deposits of "Burgess Shale Type" have been recently complemented by other types of exceptional preservation. Together with a remarkable growth in knowledge about the environments that these early animals lived in, these discoveries have long exerted a fascination and strong influence on views on the origins of animals, and indeed, the nature of evolution itself. Attention is now shifting to the period of time just before animals become common, at the base of the Cambrian and in the preceding Ediacaran Period. Remarkable though the Burgess Shale deposits have been, a substantial gap still exists in our knowledge of the earliest animals. Nevertheless, the fossils from this most remarkable period of evolutionary history continue to exert a strong influence on many aspects of animal evolution, not least recent theories about developmental evolution.

  16. New genomic and fossil data illuminate the origin of enamel.

    Science.gov (United States)

    Qu, Qingming; Haitina, Tatjana; Zhu, Min; Ahlberg, Per Erik

    2015-10-01

    Enamel, the hardest vertebrate tissue, covers the teeth of almost all sarcopterygians (lobe-finned bony fishes and tetrapods) as well as the scales and dermal bones of many fossil lobe-fins. Enamel deposition requires an organic matrix containing the unique enamel matrix proteins (EMPs) amelogenin (AMEL), enamelin (ENAM) and ameloblastin (AMBN). Chondrichthyans (cartilaginous fishes) lack both enamel and EMP genes. Many fossil and a few living non-teleost actinopterygians (ray-finned bony fishes) such as the gar, Lepisosteus, have scales and dermal bones covered with a proposed enamel homologue called ganoine. However, no gene or transcript data for EMPs have been described from actinopterygians. Here we show that Psarolepis romeri, a bony fish from the the Early Devonian period, combines enamel-covered dermal odontodes on scales and skull bones with teeth of naked dentine, and that Lepisosteus oculatus (the spotted gar) has enam and ambn genes that are expressed in the skin, probably associated with ganoine formation. The genetic evidence strengthens the hypothesis that ganoine is homologous with enamel. The fossil evidence, further supported by the Silurian bony fish Andreolepis, which has enamel-covered scales but teeth and odontodes on its dermal bones made of naked dentine, indicates that this tissue originated on the dermal skeleton, probably on the scales. It subsequently underwent heterotopic expansion across two highly conserved patterning boundaries (scales/head-shoulder and dermal/oral) within the odontode skeleton.

  17. Late Early Permian continental ichnofauna from Lake Kemp, north-central Texas, USA

    Science.gov (United States)

    Lucas, S.G.; Voigt, S.; Lerner, A.J.; Nelson, W.J.

    2011-01-01

    Continental trace fossils of Early Permian age are well known in the western United States from Wolfcampian (~. Asselian to Artinskian) strata, but few examples are known from Leonardian (~. Kungurian) deposits. A substantial ichnofauna from strata of the lower part of the Clear Fork Formation at Lake Kemp, Baylor County, Texas, augments the meager North American record of Leonardian continental trace fossil assemblages. Ichnofossils at Lake Kemp occur in the informally-named Craddock dolomite member of the Clear Fork Formation, which is 12-15. m above the local base of the Clear Fork. The trace-bearing stratum is an up-to-0.3. m thick, laminated to flaser-bedded, dolomitic siltstone that also contains mud cracks, raindrop impressions, microbially induced mat structures, and some land-plant impressions. We interpret the Craddock dolomite member as the feather-edge of a marine transgressive carbonate deposit of an irregular coastline marked by shallow bays or estuaries on the eastern shelf of the Midland basin, and the trace-fossil-bearing stratum at Lake Kemp is an unchannelized flow deposit on a muddy coastal plain. The fossil site at Lake Kemp yields a low to moderately diverse fauna of invertebrate and vertebrate traces. A sparse invertebrate ichnofauna consists of arthropod feeding and locomotion traces assigned to Walpia cf. W. hermitensis White, 1929 and Diplichnites gouldi Gevers in Gevers et al., 1971. Tetrapod footprints are most common and assigned to Batrachichnus salamandroides (Geinitz, 1861), cf. Amphisauropus kablikae (Geinitz and Deichm??ller, 1882), and Dromopus lacertoides (Geinitz, 1861), which represent small temnospondyl, seymouriamorph, and basal sauropsid trackmakers. Both the traces and sedimentary features of the fossil horizon indicate a freshwater setting at the time of track formation, and the trace assemblage represents the Scoyenia ichnofacies and the Batrachichnus ichnofacies in an overbank environment with sheet flooding and shallow

  18. 中新世水杉叶片和白垩纪松型球果化石中的挥发性成分%Volatiles from Two Gymnosperm Fossils: Miocene Leaves of Metasequoia glyptostroboides and Early Cretaceous Seed Cone of Pityostrobus spp.

    Institute of Scientific and Technical Information of China (English)

    赵友兴; 武素功; 张和; 罗晓东; 刘玉清; 周俊

    2007-01-01

    Fifty-one and nineteen compounds were detected respectively from the volatile extracts from the fossils of Miocene leaves of Metasequoia glyptostroboides and early Cretaceous seed cone of Pityostrobus spp. by gas chromatography-mass spectrometry (GC-MS) analysis. These compounds were found belonging to n-alkanes, n-alkenes, n-alkanols, long chain fatty acids and their esters, phthalates, terpenoids and aromatic compounds, and three compounds of them, abietane diterpenoid, heptadecanoic acid and retene were considered as biomarkers for gymnosperm plants. Fig 1, Tab 2, Ref 22%采用气相色谱-质谱联用分析技术从中新世水杉叶片和白垩纪松型球果两种裸子植物化石中分别鉴定了51个和19个挥发性成分,类型涉及烷烃、烷烯、烷醇、长链脂肪酸及其酯、邻苯二甲酸酯、萜类和芳香族化合物.其中3种成分--松香烷型二萜、饱和十七碳脂肪酸和惹烯是裸子植物的生物标志分子.图1 表2 参22

  19. 西准噶尔玛依勒山一带早泥盆世生物化石的发现及其意义%Discovery and significance of Early Devonian fossils in the Mayileshan area,western Junggar,Xinjiang,China

    Institute of Scientific and Technical Information of China (English)

    魏荣珠; 董挨管; 李嵩; 王瑞军; 柴金钟

    2011-01-01

    新疆北部西准噶尔地区玛依勒山一带泥盆纪火山碎屑岩、陆源碎屑沉积岩建造较发育,以往资料一般将其划为中泥盆统.本次工作在该套地层中发现了大量属于早泥盆世的化石,为该套地层的时代确定提供了依据.根据岩石地层单位将该区泥盆系划分为下泥盆统马拉苏组和中泥盒统库鲁木迪组.%In the Mayileshan area, western Junggar, northern Xinjiang, Devonian volcaniclastic rocks and the construction of clastic sedimentary rocks are comparative development. In the previous data, they generally were classified as Middle Devonian. In this work, a large number of fossils belonged to Early Devonian were found in the strata, which provided the basis for the age determination of the strata. According to lithostratigraphic units, Devonian was divided into the Lower Devonian Malassu Formation and the Middle Devonian Kourou Moody Formation.

  20. Maturation experiments reveal bias in the fossil record of feathers

    Science.gov (United States)

    McNamara, Maria; Field, Daniel

    2016-04-01

    The evolutionary history of birds and feathers is a major focus in palaeobiology and evolutionary biology. Diverse exceptionally preserved birds and feathered dinosaurs from Jurassic and Cretaceous biotas in China have provided pivotal evidence of early feathers and feather-like integumentary features, but the true nature of many of these fossil soft tissues is still debated. Interpretations of feathers at intermediate developmental stages (i.e. Stages II, III and IV) and of simple quill-like (Stage I) feathers are particularly controversial. This reflects key uncertainties relating to the preservation potential of feathers at different evolutionary-developmental stages, and to the relative preservation potential of diagnostic features of Stage I feathers and hair. To resolve these issues, we used high pressure-high temperature autoclave experiments to simulate the effects of burial on modern feathers from the Black Coucal (Centropus grilii) and Common Starling (Sturnus vulgaris), and on human hair. Our results reveal profound differences in the recalcitrance of feathers of different types during maturation: Stage I and Stage V feathers retain diagnostic morphological and ultrastructural details following maturation, whereas other feather types do not. Further, the morphology and arrangement of certain ultrastructural features diagnostic of Stages III and IV, e.g. barbules, are preferentially lost during maturation. These results indicate a pervasive bias in the fossil record of feathers, whereby preservation of feathers at Stages I and V is favored. Critical stages in the evolution of feathers, i.e. Stages II, III and IV, are less likely to be preserved and more likely to be misinterpreted as feathers at earlier developmental stages. Our discovery has major implications for our understanding of the fidelity of the fossil record of feathers and provides a framework for testing the significance of putative examples of fossil feathers at different developmental

  1. A fossil flora from the Frontier formation of southwestern Wyoming

    Science.gov (United States)

    Knowlton, F.H.

    1917-01-01

    This paper deals with a small but important fossil flora, now known to be of Colorado age, from the vicinity of Cumberland, Lincoln County, Wyo. It was for many years thought to be of Jurassic age, and only within the last decade has its stratigraphic position been established. Although small in number of species, this flora offers information bearing on the physical and climatic conditions that prevailed during early Upper Cretaceous time in this region, and, moreover, it furnishes a series of stratigraphic marks that may be used in the recognition of this horizon elsewhere.

  2. U-Pb geochronology of the Santa Cruz Formation (early Miocene) at the Río Bote and Río Santa Cruz (southernmost Patagonia, Argentina): Implications for the correlation of fossil vertebrate localities

    Science.gov (United States)

    Cuitiño, José I.; Fernicola, Juan Carlos; Kohn, Matthew J.; Trayler, Robin; Naipauer, Maximiliano; Bargo, M. Susana; Kay, Richard F.; Vizcaíno, Sergio F.

    2016-10-01

    The early Miocene Santa Cruz Formation (SCF) in southern Patagonia hosts the Santacrucian South American Land Mammal Age (SALMA), whose age is known mainly from exposures along the Atlantic coast. Zircon U-Pb ages were obtained from intercalated tuffs from four inland sections of the SCF: 17.36 ± 0.63 Ma for the westernmost Río Bote locality, and 17.04 ± 0.55 Ma-16.32 ± 0.62 Ma for central Río Santa Cruz localities. All ages agree with the bounding age of underlying marine units and with equivalent strata in coastal exposures. New ages and available sedimentation rates imply time spans for each section of ∼18.2 to 17.36 Ma for Río Bote and 17.45-15.63 Ma for central Río Santa Cruz (Burdigalian). These estimates support the view that deposition of the SCF began at western localities ∼1 Ma earlier than at eastern localities, and that the central Río Santa Cruz localities expose the youngest SCF in southern Santa Cruz Province. Associated vertebrate faunas are consistent with our geochronologic synthesis, showing older (Notohippidian) taxa in western localities and younger (Santacrucian) taxa in central localities. The Notohippidian fauna (19.0-18.0 Ma) of the western localities is synchronous with Pinturan faunas (19.0-18.0 Ma), but older than Santacrucian faunas of the Río Santa Cruz (17.2-15.6 Ma) and coastal localities (18.0-16.2 Ma). The Santacrucian faunas of the central Río Santa Cruz localities temporally overlap Colloncuran (15.7 Ma), Friasian (16.5 Ma), and eastern Santacrucian faunas.

  3. Extant-only comparative methods fail to recover the disparity preserved in the bird fossil record.

    Science.gov (United States)

    Mitchell, Jonathan S

    2015-09-01

    Most extant species are in clades with poor fossil records, and recent studies of comparative methods show they have low power to infer even highly simplified models of trait evolution without fossil data. Birds are a well-studied radiation, yet their early evolutionary patterns are still contentious. The fossil record suggests that birds underwent a rapid ecological radiation after the end-Cretaceous mass extinction, and several smaller, subsequent radiations. This hypothesized series of repeated radiations from fossil data is difficult to test using extant data alone. By uniting morphological and phylogenetic data on 604 extant genera of birds with morphological data on 58 species of extinct birds from 50 million years ago, the "halfway point" of avian evolution, I have been able to test how well extant-only methods predict the diversity of fossil forms. All extant-only methods underestimate the disparity, although the ratio of within- to between-clade disparity does suggest high early rates. The failure of standard models to predict high early disparity suggests that recent radiations are obscuring deep time patterns in the evolution of birds. Metrics from different models can be used in conjunction to provide more valuable insights than simply finding the model with the highest relative fit. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

  4. Trace fossils in coal-bearing sequences

    Energy Technology Data Exchange (ETDEWEB)

    Pollard, J.E.

    1988-03-01

    In the past decade trace fossils have been recorded extensively from coal-bearing sediments, differing widely in facies, age and location. Westphalian or Stephanian 'coal-measures' in Britain, Europe and Eastern Canada contain an ichnofauna produced by invertebrates and/or vertebrates in upper delta plain sediments. This contrasts with the marine-related lower delta plain ichnofaunas known from Pennsylvanian rocks of the United States and Permian Gondwana 'coal-measures' of South Africa. Deltaic complexes of Middle Jurassic age in the North Sea basin and Upper Cretaceous age in North America contain marine trace fossils and dinosaur footprints in coastal coal- bearing facies. These case histories illustrate the importance of trace fossils both in facies analysis of coal-bearing sequences and in recording the presence of animals rarely known as body fossils in such clastic sediments. 80 refs., 5 figs.

  5. Evolution: Fossil Ears and Underwater Sonar.

    Science.gov (United States)

    Lambert, Olivier

    2016-08-22

    A key innovation in the history of whales was the evolution of a sonar system together with high-frequency hearing. Fossils of an archaic toothed whale's inner ear bones provide clues for a stepwise emergence of underwater echolocation ability.

  6. Biodiversity Risks from Fossil Fuel Extraction

    National Research Council Canada - National Science Library

    N. Butt; H. L. Beyer; J. R. Bennett; D. Biggs; R. Maggini; M. Mills; A. R. Renwick; L. M. Seabrook; H. P. Possingham

    2013-01-01

    .... Although fossil fuel (FF) extraction has traditionally been seen as a temporary and spatially limited perturbation to ecosystems , even local or limited biodiversity loss can have large cascade effects on ecosystem function and productivity...

  7. Fossil fuels in the 21st century.

    Science.gov (United States)

    Lincoln, Stephen F

    2005-12-01

    An overview of the importance of fossil fuels in supplying the energy requirements of the 21st century, their future supply, and the impact of their use on global climate is presented. Current and potential alternative energy sources are considered. It is concluded that even with substantial increases in energy derived from other sources, fossil fuels will remain a major energy source for much of the 21st century and the sequestration of CO2 will be an increasingly important requirement.

  8. Sustainable generation of bioenergy in fluidized bed boilers

    Energy Technology Data Exchange (ETDEWEB)

    Offenbacher, Elmar

    2010-07-01

    Full text: These days, reflecting a growing demand of heat and power, increasing cost for fossil fuels and more environmental issues (limitation of greenhouse gases, regulations for landfill etc.), the sustainable conversion of renewable fuels to bioenergy is becoming increasingly important. Renewable fuels cover a wide range, from traditional wood, bark, harvesting residues to all kind of sludges, and contain a remarkable calorific value that can easily compete with fossil fuels such as brown coal and lignite. The combustion of these renewable fuels does not create any greenhouse gases. The favourable technology for combusting renewable fuels is the fluidized bed technology, bubbling fluidized bed and circulating fluidized bed, as this system provides maximum fuel flexibility combined with high combustion efficiency and low emissions. Neither a variation of the water content and the heating value nor different sources of the material streams have a negative impact on the combustion. Fluidized bed boilers can switch from one fuel to the other quiet easily and can also be fired with conventional fuels that ensure a smooth and reliable generation of process heat and/or power in any case. The reasons that make fluidized bed boilers the most sustainable combustion technology for renewable fuels are various: The main feature of this technology is the principle of staged combustion of the fuel: The oxygen level in the fluidized bed is limited and hence only a part of the fuel is combusted, whereas the rest of the fuel is gasified. The staged combustion concept results in a homogenous temperature profile of less than 850 deg. C in the furnace and low NO{sub x} emission as a consequence. The turbulences in the furnace result and an efficient combustion that is combined with very low CO and TOC emissions in the flue gas. This paper will describe design features of the latest fluidized bed technology especially suitable for firing renewable fuels, and the research results of

  9. Linking megathrust earthquakes to faulting and mineral vein formation in a fossil accretionary complex

    Science.gov (United States)

    Dielforder, Armin; Herwegh, Marco; Berger, Alfons

    2015-04-01

    Geodetic and seismological data recorded at active subduction zones suggest that megathrust earthquakes induce transient stress changes in the upper plate, which shift the wedge into an unstable state and trigger >Mw 6 aftershocks. These stress changes have, however, never been linked to geological structures that are preserved within fossil accretionary wedges, although plate interface of palaeo-subduction zones has been studied. The conditions under which accretionary wedges fail have therefore remained controversial. Here we show that faulting and associated vein formation in the palaeo-accretionary complex of the European Alps record stress changes generated by the subduction earthquake cycle. Our data integrate wedge deformation over millions of years but still demonstrate the dominance of specific fracture modes at different depths within the wedge. We trace the subduction of sediments by means of the 87Sr/86Sr isotope-systematics of mineral veins, which became more radiogenic at deeper levels. By combining our field observations and geochemical data with a dynamic Mohr-Coulomb wedge analysis, we show that early veins were formed in shallow levels by bedding-parallel shear during coseismic compression of the outer wedge. In contrast, later veins originated at deeper levels during normal faulting and extensional fracturing recording coseismic extension of the inner wedge. Our study shows how mineral veins can be used to reveal the dynamics of outer and inner wedges, which response in opposite ways to megathrust earthquakes by compressional and extensional faulting, respectively. We emphasise, that coseismic fracturing implicates an increase in permeability within the hanging wall of megathrusts. Understanding how fractures are generated throughout the subduction earthquake cycle is therefore essential to better contstrain the nature of postseismic fluid flow and to assess the seismic hazard of hydraulically driven aftershocks.

  10. Primate diversification inferred from phylogenies and fossils.

    Science.gov (United States)

    Herrera, James P

    2017-09-14

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

  11. The shadow price of fossil groundwater

    Science.gov (United States)

    Bierkens, Marc F. P.; Reinhard, Stijn; de Bruijn, Jens A.; Wada, Yoshihide

    2017-04-01

    The expansion of irrigated agriculture into areas with limited precipitation and surface water during the growing season has greatly increased the use of fossil groundwater (Wada et al., 2012). As a result, the depletion rate of fossil groundwater resources has shown an increasing rate during the last decades (Wada et al, 2010; Konikow, 2011; Wada et al., 2012; De Graaf et al. 2015; Ritchy et al., 2015). Although water pricing has been used extensively to stimulate efficient application of water to create maximum value (e.g. Medellín-Azuara et al., 2012; Rinaudo et al., 2012; Dinar et al., 2015), it does not preclude the use of non-renewable water resources. Here, we use a global hydrological model and historical crop production and price data to assess the shadow price of non-renewable or fossil groundwater applied to major crops in countries that use large quantities of fossil groundwater. Our results show that shadow prices for many crops are very low, indicating economically inefficient or even wasteful use of fossil groundwater resources. Using India as an example, we show that small changes in the crop mix could lead to large reductions in fossil groundwater use or alternatively, create additional financial means to invest in water saving technologies. Our study thus provides a hydro-economic basis to further the sustainable use of finite groundwater resources.

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

    DEFF Research Database (Denmark)

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

    2015-01-01

    A cliff exposure of the Eocene Lillebælt Clay Formation, on the Røsnæs peninsula of Zealand, Denmark, has yielded a diverse trace-fossil assemblage. The trace fossils are described formally for the first time and assigned to Phymatoderma melvillensis, unnamed clusters of small burrows, Ophiomorpha...... nodosa, Spongeliomorpha isp., Dreginozoum beckumensis, Bichordites isp., Chondrites isp., Atollites zitteli? and ?Rhizocorallium isp. The preservation of the trace fossils is strongly related to early diagenetic enhancement. The trace-fossil assemblage is dominated by a combination of dwelling...... and feeding burrows. The bioturbation took place in very clean clay of a shelf setting far offshore. The trace-fossil assemblage is indicative of the distal Cruziana ichnofacies....

  13. Bed bug deterrence

    Directory of Open Access Journals (Sweden)

    Haynes Kenneth F

    2010-09-01

    Full Text Available Abstract A recent study in BMC Biology has determined that the immature stage of the bed bug (the nymph signals its reproductive status to adult males using pheromones and thus avoids the trauma associated with copulation in this species. The success of this nymphal strategy of deterrence is instructive. Against the background of increasing problems with bed bugs, this research raises the question whether pheromones might be used to control them. See research article http://www.biomedcentral.com/1741-7007/8/121

  14. in Spouted Bed

    Directory of Open Access Journals (Sweden)

    Bronislaw Buczek

    2013-01-01

    Full Text Available Samples of active coke, fresh and spent after cleaning flue gases from communal waste incinerators, were investigated. The outer layers of both coke particles were separately removed by comminution in a spouted bed. The samples of both active cokes were analysed by means of densities, mercury porosimetry, and adsorption technique. Remaining cores were examined to determine the degree of consumption of coke by the sorption of hazardous emissions (SO2, HCl, and heavy metals through its bed. Differences in contamination levels within the porous structure of the particles were estimated. The study demonstrated the effectiveness of commercial active coke in the cleaning of flue gases.

  15. The Safety of Hospital Beds

    Science.gov (United States)

    Gervais, Pierre; Pooler, Charlotte; Merryweather, Andrew; Doig, Alexa K.; Bloswick, Donald

    2015-01-01

    To explore the safety of the standard and the low hospital bed, we report on a microanalysis of 15 patients’ ability to ingress, move about the bed, and egress. The 15 participants were purposefully selected with various disabilities. Bed conditions were randomized with side rails up or down and one low bed with side rails down. We explored the patients’ use of the side rails, bed height, ability to lift their legs onto the mattress, and ability to turn, egress, and walk back to the chair. The standard bed was too high for some participants, both for ingress and egress. Side rails were used by most participants when entering, turning in bed, and exiting. We recommend that side rails be reconsidered as a means to facilitate in-bed movement, ingress, and egress. Furthermore, single deck height settings for all patients are not optimal. Low beds as a safety measure must be re-evaluated. PMID:28462302

  16. New hominid fossils from Member 1 of the Swartkrans formation, South Africa.

    Science.gov (United States)

    Pickering, Travis Rayne; Heaton, Jason L; Clarke, Ronald J; Sutton, Morris B; Brain, C K; Kuman, Kathleen

    2012-05-01

    Member 1 of the Swartkrans Formation is comprised of two sedimentary infills, the Lower Bank (LB) and the Hanging Remnant (HR). Together, the LB and HR preserve fossils of early Homo and Paranthropus robustus, Earlier Stone Age lithic artifacts, purported bone digging tools and butchered animal bones. Collectively, this evidence was the first to establish the co-existence of two early Pleistocene hominid species and also led to inferences of plant root harvesting and meat-eating by one or both of those species. P. robustus is the more abundant of the two hominids at Swartrkrans, represented in Member 1 by hundreds of fossils that derive from at least 99 individuals. Thus, Swartkrans Member 1 stands as the world's single largest repository of that extinct species. Here we add to the Member 1 sample of hominid fossils with descriptions of 14 newly discovered specimens.

  17. Experimental mineralization of crustacean eggs: new implications for the fossilization of Precambrian-Cambrian embryos

    Science.gov (United States)

    Hippler, D.; Hu, N.; Steiner, M.; Scholtz, G.; Franz, G.

    2012-05-01

    Phosphatized globular microfossils from the Ediacaran and lower Cambrian of South China represent an impressive record of early animal evolution and development. However, their phylogenetic affinity is strongly debated. Understanding key processes and conditions that cause exceptional egg and embryo preservation and fossilization are crucial for a reliable interpretation of their phylogenetic position. We conducted phosphatization experiments on eggs of the marbled crayfish Procambarus that indicate a close link between early mineralization and rapid anaerobic decay of the endochorional envelope. Our experiments replicated the different preservational stages of degradation observed in the fossil record. Stabilization of the spherical morphology was achieved by pre-heating of the eggs. Complete surface mineralization occurred under reduced conditions within one to two weeks, with fine-grained brushite (CaHPO4 · 2H2O) and calcite. The mechanisms of decay, preservation of surface structures, and mineral replacement in the experiment were likely similar during fossilization of Cambrian embryos.

  18. Age and context of the oldest known hominin fossils from Flores

    DEFF Research Database (Denmark)

    Brumm, Adam; van den Bergh, Gerrit D.; Storey, Michael

    2016-01-01

    Recent excavations at the early Middle Pleistocene site of Mata Menge in the So'a Basin of central Flores, Indonesia, have yielded hominin fossils attributed to a population ancestral to Late Pleistocene Homo floresiensis. Here we describe the age and context of the Mata Menge hominin specimens...... and associated archaeological findings. The fluvial sandstone layer from which the in situ fossils were excavated in 2014 was deposited in a small valley stream around 700 thousand years ago, as indicated by 40Ar/39 Ar and fission track dates on stratigraphically bracketing volcanic ash and pyroclastic density...... current deposits, in combination with coupled uranium-series and electron spin resonance dating of fossil teeth. Palaeoenvironmental data indicate a relatively dry climate in the So'a Basin during the early Middle Pleistocene, while various lines of evidence suggest the hominins inhabited a savannah...

  19. Stable carbon isotope ratios and intrinsic water-use efficiency of Miocene fossil leaves compared to modern congeners

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, J.D.; Zhang, J.; Rember, W.C.; Jennings, D.; Larson, P. (Univ. of Idaho, Moscow, ID (United States))

    1994-06-01

    Miocene fossil leaves of forest trees were extracted from the Clarkia, Idaho fossil beds and their stable carbon isotope ratios were analyzed. Fossils had higher lignin concentrations and lower cellulose concentrations that modern leaves due to diagenesis and the HF used to extract the fossils. Therefore, [delta][sup 13]C of extracted fossil lignin was compared to that of modern lignin. Fossil lignin [delta][sup 13]C was significantly different from that of congeneric modern leaves (paired t-test, P<0.0001), but was 1.9% less negative. Gymnosperms (Metasequoia, Taxodium) were less negative than angiosperms (e.g., Magnolia, Quercus, Acer, Persea), but no difference between evergreen and deciduous species was detected. Using published estimates of the concentration and [delta][sup 13]C of atmospheric CO[sub 2] during the Miocene was estimated the CO[sub 2] partial pressure gradient across the stomata (intrinsic water-use efficiency). Intrinsic water-use efficiency was at least 70% higher during this past [open quotes]greenhouse[close quotes] period than at present.

  20. Cell differentiation and germ-soma separation in Ediacaran animal embryo-like fossils

    Science.gov (United States)

    Chen, Lei; Xiao, Shuhai; Pang, Ke; Zhou, Chuanming; Yuan, Xunlai

    2014-12-01

    Phosphorites of the Ediacaran Doushantuo Formation (~600 million years old) yield spheroidal microfossils with a palintomic cell cleavage pattern. These fossils have been variously interpreted as sulphur-oxidizing bacteria, unicellular protists, mesomycetozoean-like holozoans, green algae akin to Volvox, and blastula embryos of early metazoans or bilaterian animals. However, their complete life cycle is unknown and it is uncertain whether they had a cellularly differentiated ontogenetic stage, making it difficult to test their various phylogenetic interpretations. Here we describe new spheroidal fossils from black phosphorites of the Doushantuo Formation that have been overlooked in previous studies. These fossils represent later developmental stages of previously published blastula-like fossils, and they show evidence for cell differentiation, germ-soma separation, and programmed cell death. Their complex multicellularity is inconsistent with a phylogenetic affinity with bacteria, unicellular protists, or mesomycetozoean-like holozoans. Available evidence also indicates that the Doushantuo fossils are unlikely crown-group animals or volvocine green algae. We conclude that an affinity with cellularly differentiated multicellular eukaryotes, including stem-group animals or algae, is likely but more data are needed to constrain further the exact phylogenetic affinity of the Doushantuo fossils.

  1. Cell differentiation and germ-soma separation in Ediacaran animal embryo-like fossils.

    Science.gov (United States)

    Chen, Lei; Xiao, Shuhai; Pang, Ke; Zhou, Chuanming; Yuan, Xunlai

    2014-12-11

    Phosphorites of the Ediacaran Doushantuo Formation (∼600 million years old) yield spheroidal microfossils with a palintomic cell cleavage pattern. These fossils have been variously interpreted as sulphur-oxidizing bacteria, unicellular protists, mesomycetozoean-like holozoans, green algae akin to Volvox, and blastula embryos of early metazoans or bilaterian animals. However, their complete life cycle is unknown and it is uncertain whether they had a cellularly differentiated ontogenetic stage, making it difficult to test their various phylogenetic interpretations. Here we describe new spheroidal fossils from black phosphorites of the Doushantuo Formation that have been overlooked in previous studies. These fossils represent later developmental stages of previously published blastula-like fossils, and they show evidence for cell differentiation, germ-soma separation, and programmed cell death. Their complex multicellularity is inconsistent with a phylogenetic affinity with bacteria, unicellular protists, or mesomycetozoean-like holozoans. Available evidence also indicates that the Doushantuo fossils are unlikely crown-group animals or volvocine green algae. We conclude that an affinity with cellularly differentiated multicellular eukaryotes, including stem-group animals or algae, is likely but more data are needed to constrain further the exact phylogenetic affinity of the Doushantuo fossils.

  2. Experimental taphonomy and the anatomy and diversity of the earliest fossil vertebrates (Chengjiang Biota, Cambrian, China)

    Science.gov (United States)

    Purnell, Mark; Gabbott, Sarah; Murdock, Duncan; Cong, Peiyun

    2016-04-01

    The oldest fossil vertebrates are from the Lower Cambrian Chengjiang biota of China, which contains four genera of fish-like, primitive vertebrates: Haikouichthys, Myllokunmingia, Zhongjianichthys and Zhongxiniscus. These fossils play key roles in calibrating molecular clocks and informing our view of the anatomy of animals close to the origin of vertebrates, potentially including transitional forms between vertebrates and their nearest relatives. Despite the evident importance of these fossils, the degree to which taphonomic processes have affected their anatomical completeness has not been investigated. For example, some or all might have been affected by stemward slippage - the pattern observed in experimental decay of non-biomineralised chordates in which preferential decay of synapomorphies and retention of plesiomorphic characters would cause fossil taxa to erroneously occupy more basal positions than they should. This hypothesis is based on experimental data derived from decay of non-biomineralised chordates under laboratory conditions. We have expanded this analysis to include a broader range of potentially significant environmental variables; we have also compared and combined the results of experiments from several taxa to identify general patterns of chordate decay. Examination of the Chengjiang vertebrates in the light of these results demonstrates that, contrary to some assertions, experimentally derived models of phylogenetic bias are applicable to fossils. Anatomical and phylogenetic interpretations of early vertebrates that do not take taphonomic biases into account risk overestimating diversity and the evolutionary significance of differences between fossil specimens.

  3. Recent decreases in fossil-fuel emissions of ethane and methane derived from firn air.

    Science.gov (United States)

    Aydin, Murat; Verhulst, Kristal R; Saltzman, Eric S; Battle, Mark O; Montzka, Stephen A; Blake, Donald R; Tang, Qi; Prather, Michael J

    2011-08-10

    Methane and ethane are the most abundant hydrocarbons in the atmosphere and they affect both atmospheric chemistry and climate. Both gases are emitted from fossil fuels and biomass burning, whereas methane (CH(4)) alone has large sources from wetlands, agriculture, landfills and waste water. Here we use measurements in firn (perennial snowpack) air from Greenland and Antarctica to reconstruct the atmospheric variability of ethane (C(2)H(6)) during the twentieth century. Ethane levels rose from early in the century until the 1980s, when the trend reversed, with a period of decline over the next 20 years. We find that this variability was primarily driven by changes in ethane emissions from fossil fuels; these emissions peaked in the 1960s and 1970s at 14-16 teragrams per year (1 Tg = 10(12) g) and dropped to 8-10 Tg  yr(-1) by the turn of the century. The reduction in fossil-fuel sources is probably related to changes in light hydrocarbon emissions associated with petroleum production and use. The ethane-based fossil-fuel emission history is strikingly different from bottom-up estimates of methane emissions from fossil-fuel use, and implies that the fossil-fuel source of methane started to decline in the 1980s and probably caused the late twentieth century slow-down in the growth rate of atmospheric methane.

  4. New fossil seeds of Eurya (Theaceae from East Asia and their paleobiogeographic implications

    Directory of Open Access Journals (Sweden)

    Hai Zhu

    2016-06-01

    Full Text Available Eurya has an excellent fossil record in Europe, but it has only a few fossil occurrences in East Asia though this vast area houses the highest modern diversity of the genus. In this study, three-dimensionally preserved fossil seeds of Eurya stigmosa (Ludwig Mai from the late Pliocene of northwestern Yunnan, southwestern China are described. The seeds are compressed and flattened, slightly campylotropous, and nearly circular to slightly angular in shape. The surface of the seeds is sculptured by a distinctive foveolate pattern, consisting of funnel-shaped and finely pitted cells. Each seed valve contains a reniform or horseshoe-shaped embryo cavity, a characteristic condyle structure and an internal raphe. These fossil seeds represent one of the few fossil records of Eurya in East Asia. This new finding therefore largely extends the distributional ranges of Eurya during Neogene. Fossil records summarized here show that Eurya persisted in Europe until the early Pleistocene, but disappeared thereafter. The genus might have first appeared in East Asia no later than the late Oligocene, and dispersed widely in regions such as Japan, Nepal, and southwestern China.

  5. Molecular fossils of prokaryotes in ancient authigenic minerals: archives of microbial activity in reefs and mounds?

    Science.gov (United States)

    Heindel, Katrin; Birgel, Daniel; Richoz, Sylvain; Westphal, Hildegard; Peckmann, Jörn

    2016-04-01

    Molecular fossils (lipid biomarkers) are commonly used as proxies in organic-rich sediments of various sources, including eukaryotes and prokaryotes. Usually, molecular fossils of organisms transferred from the water column to the sediment are studied to monitor environmental changes (e.g., temperature, pH). Apart from these 'allochthonous' molecular fossils, prokaryotes are active in sediments and mats on the seafloor and leave behind 'autochthonous' molecular fossils in situ. In contrast to many phototrophic organisms, most benthic sedimentary prokaryotes are obtaining their energy from oxidation or reduction of organic or inorganic substrates. A peculiarity of some of the sediment-thriving prokaryotes is their ability to trigger in situ mineral precipitation, often but not only due to metabolic activity, resulting in authigenic rocks (microbialites). During that process, prokaryotes are rapidly entombed in the mineral matrix, where the molecular fossils are protected from early (bio)degradation. In contrast to other organic compounds (DNA, proteins etc.), molecular fossils can be preserved over very long time periods (millions of years). Thus, molecular fossils in authigenic mineral phases are perfectly suitable to trace microbial activity back in time. Among the best examples of molecular fossils, which are preserved in authigenic rocks are various microbialites, forming e.g. in phototrophic microbial mats and at cold seeps. Microbialite formation is reported throughout earth history. We here will focus on reefal microbialites form the Early Triassic and the Holocene. After the End-Permian mass extinction, microbialites covered wide areas on the ocean margins. In microbialites from the Griesbachian in Iran and Turkey (both Neotethys), molecular fossils of cyanobacteria, archaea, anoxygenic phototrophs, and sulphate-reducing bacteria indicate the presence of layered microbial mats on the seafloor, in which carbonate precipitation was induced. In association with

  6. Molecular fossils and the late rise of oxygenic photosynthesis

    Science.gov (United States)

    Brocks, J. J.

    2012-04-01

    Biomarkers are the molecular fossils of natural products such as lipids and pigments. They can yield a wealth of information about early microbial ecosystems and are particularly valuable when preserved in > 1 billion-year old (Ga) sedimentary rocks where conventional fossils are often lacking. Therefore, in 1999, the detection of traces of biomarkers in 2.5 to 2.7 Ga shales from Western Australia (Brocks et al. 1999, Summons et al. 1999) was celebrated as a breakthrough. The discovery, which was later confirmed by several independent studies, led to far reaching conclusions about the early evolution of oxygenic photosynthesis (Summons et al. 1999) and ancestral eukaryotes (Brocks et al. 1999). However, here we present new data based on the carbon isotopic composition of solidified hydrocarbons (Rasmussen et al. 2008) and the spatial distribution of liquid hydrocarbons within the original 2.5 and 2.7 Ga shales (Brocks 2011) that demonstrate that the molecules must have entered the rocks much later in Earth's history and therefore provide no information about the Archean (>2.5 Ga) biosphere or environment. The elimination of the Archean biomarker data has immense implications for our understanding of Earth's early biosphere. 2-Methylhopanes have been interpreted as evidence for the existence of cyanobacteria at 2.7 Ga, about ~300 million years before the atmosphere became mildly oxygenated in the Great Oxidation Event (GOE; between 2.45 and 2.32 Ga). Now, the oldest direct fossil evidence for cyanobacteria reverts back to 2.15 Ga, and the most ancient robust sign for oxygenic photosynthesis becomes the GOE itself. Moreover, the presence of steranes has been interpreted as evidence for the existence of ancestral eukaryotes at 2.7 Ga. However, without the steranes, the oldest fossil evidence for the domain falls into the range ~1.78-1.68 Ga. Recognition that the biomarkers from Archean rocks are not of Archean age renders permissive hypotheses about a late evolution

  7. A Brief Analysis of Oral Fossilization of English Major Students

    Institute of Scientific and Technical Information of China (English)

    SUN Jian-xia

    2014-01-01

    This paper on the basis of former studies and researches has analyzed fossilization particularly oral fossilization. Further more, this paper has analyzed the reasons of fossilization and at the same time put forward some tentative solutions to reduce or avoid fossilization. Hope that this paper can offer some help for both the second language learners and teachers.

  8. MULTISTAGE FLUIDIZED BED REACTOR

    Science.gov (United States)

    Jonke, A.A.; Graae, J.E.A.; Levitz, N.M.

    1959-11-01

    A multistage fluidized bed reactor is described in which each of a number of stages is arranged with respect to an associated baffle so that a fluidizing gas flows upward and a granular solid downward through the stages and baffles, whereas the granular solid stopsflowing downward when the flow of fluidizing gas is shut off.

  9. Fluidized bed combustion chamber

    Energy Technology Data Exchange (ETDEWEB)

    Kullendorff, A.; Wikner, J.

    1985-03-25

    The chamber is confined in a pressure vessel. The lower part of the chamber has tilted parallel gutters up to the height of the fluidized bed. The slope of the gutter walls is 5 degrees-15 degrees and the top area of the gutters is 1.3 to 3 times larger than their bottom.

  10. Bed Bug Myths

    Science.gov (United States)

    Learn the truth about bed bugs, such as how easy they are to see with the naked eye, their preferred habitat, whether they transmit diseases, their public health effects, and whether pesticides are the best way to deal with an infestation.

  11. Surviving Bed Rest

    Science.gov (United States)

    ... your pregnancy — and your bed rest start a family tree that you can share with your child someday firm up your baby-name choices; use books and websites for ideas organize photo albums read anything — ... people (friends and family) whom you know will probably give gifts build ...

  12. Comparing primate crania: The importance of fossils.

    Science.gov (United States)

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

    2016-10-01

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

  13. A fossil wood flora from King George Island: ecological implications for an Antarctic eocene vegetation

    NARCIS (Netherlands)

    Poole, I.J.; Hunt, Richard J.; Cantrill, David J.

    2001-01-01

    Early Tertiary sediments of the Antarctic Peninsula region continue to yield a rich assemblage of well-preserved fossil dicotyledonous angiosperm wood. The wood flora under consideration is from the Collins Glacier region on Fildes Peninsula, King George Island and is derived from tuffaceous

  14. A fossil wood flora from King George Island: ecological implications for an Antarctic eocene vegetation

    NARCIS (Netherlands)

    Poole, I.J.; Hunt, Richard J.; Cantrill, David J.

    2001-01-01

    Early Tertiary sediments of the Antarctic Peninsula region continue to yield a rich assemblage of well-preserved fossil dicotyledonous angiosperm wood. The wood flora under consideration is from the Collins Glacier region on Fildes Peninsula, King George Island and is derived from tuffaceous sedimen

  15. A New Genus of Fossil Cycads Yixianophyllum gen. nov. from the Late Jurassic Yixian Formation, Western Liaoning, China

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    A new genus of fossil Cycads, Yixianophyllum gen. nov., is reported here. The specimens were collected from the southern hill of Jinjiagou village, Toudaohezi Town, Yixian County, western Liaoning Province, China. The fossil plant-bearing bed belongs to the lower part, the Zhuanchengzi bed, of the Upper Jurassic Yixian Formation (Yixianian). The new genus in leaf shape, venation and epidermal structure shows a transitional form between Mesozoic Cycads (Ctenis, Nilssonia) and modern Cycads (Stangeria and Encephalartos). Since the features of these specimens differ from any known genera of Cycads, a new genetic name Yixianophyllum is proposed for these leaves. Typical species, Yixianophyllum jinjiagouense gen. et sp. nov. is described here. A supposed evolutionary tendency of Cycadean leaf-forms with Taeniopteris-type is discussed.

  16. Present knowledge on the fossil mammals record from Chile; Estado actual del conocimiento de los mamiferos fosiles de Chile

    Energy Technology Data Exchange (ETDEWEB)

    Canto, J.; Yanez, J.; Rovira, J.

    2010-07-01

    An updated revision is presented regarding fossil mammals of aquatic and terrestrial environments. This update includes up to year 2008. Those registrations of doubtful assignation or that couldn't be confirmed were not considered in this review. These new registrations are classified in four groups of time that extend from the Late Eocene-Early Oligocene to the Pleistocene-Recent. The evidence shows that the greatest quantity of fossils are concentrated from the Early Miocene to the Middle Miocene reaching 37 (41.5%) genus of a total of 77 and 54 (49.5%) fossil species of a total of 89. It is observed a significant increase in works devoted to paleontology of mammal fossils in Chile between 1981-2008. (Author)

  17. Macroevolutionary developmental biology: Embryos, fossils, and phylogenies.

    Science.gov (United States)

    Organ, Chris L; Cooper, Lisa Noelle; Hieronymus, Tobin L

    2015-10-01

    The field of evolutionary developmental biology is broadly focused on identifying the genetic and developmental mechanisms underlying morphological diversity. Connecting the genotype with the phenotype means that evo-devo research often considers a wide range of evidence, from genetics and morphology to fossils. In this commentary, we provide an overview and framework for integrating fossil ontogenetic data with developmental data using phylogenetic comparative methods to test macroevolutionary hypotheses. We survey the vertebrate fossil record of preserved embryos and discuss how phylogenetic comparative methods can integrate data from developmental genetics and paleontology. Fossil embryos provide limited, yet critical, developmental data from deep time. They help constrain when developmental innovations first appeared during the history of life and also reveal the order in which related morphologies evolved. Phylogenetic comparative methods provide a powerful statistical approach that allows evo-devo researchers to infer the presence of nonpreserved developmental traits in fossil species and to detect discordant evolutionary patterns and processes across levels of biological organization.

  18. Fossil fuels in a trillion tonne world

    Science.gov (United States)

    Scott, Vivian; Haszeldine, R. Stuart; Tett, Simon F. B.; Oschlies, Andreas

    2015-05-01

    The useful energy services and energy density value of fossil carbon fuels could be retained for longer timescales into the future if their combustion is balanced by CO2 recapture and storage. We assess the global balance between fossil carbon supply and the sufficiency (size) and capability (technology, security) of candidate carbon stores. A hierarchy of value for extraction-to-storage pairings is proposed, which is augmented by classification of CO2 containment as temporary (100,000 yr). Using temporary stores is inefficient and defers an intergenerational problem. Permanent storage capacity is adequate to technically match current fossil fuel reserves. However, rates of storage creation cannot balance current and expected rates of fossil fuel extraction and CO2 consequences. Extraction of conventional natural gas is uniquely holistic because it creates the capacity to re-inject an equivalent tonnage of carbon for storage into the same reservoir and can re-use gas-extraction infrastructure for storage. By contrast, balancing the extraction of coal, oil, biomass and unconventional fossil fuels requires the engineering and validation of additional carbon storage. Such storage is, so far, unproven in sufficiency.

  19. Bathing a patient in bed

    Science.gov (United States)

    ... medlineplus.gov/ency/patientinstructions/000427.htm Bathing a patient in bed To use the sharing features on this page, please enable JavaScript. Some patients cannot safely leave their beds to bathe. For ...

  20. VA National Bed Control System

    Data.gov (United States)

    Department of Veterans Affairs — The VA National Bed Control System records the levels of operating, unavailable and authorized beds at each VAMC, and it tracks requests for changes in these levels....

  1. Molecular fossils in Cretaceous condensate from western India

    Indian Academy of Sciences (India)

    Sharmila Bhattacharya; Suryendu Dutta; Ratul Dutta

    2014-07-01

    The present study reports the biomarker distribution of condensate belonging to the early Cretaceous time frame using gas chromatography-mass spectrometry (GC–MS). The early Cretaceous palaeoenvironment was inscribed into these molecular fossils which reflected the source and conditions of deposition of the condensate. The saturate fraction of the condensate is characterized by normal alkanes ranging from -C9 to -C29} (CPI-1.13), cycloalkanes and C14 and C15 sesquiterpanes. The aromatic fraction comprises of naphthalene, phenanthrene, their methylated derivatives and cyclohexylbenzenes. Isohexylalkylnaphthalenes, a product of rearrangement process of terpenoids, is detected in the condensate. Several aromatic sesquiterpenoids and diterpenoids have been recorded. Dihydro-ar-curcumene, cadalene and ionene form the assemblage of sesquiterpenoids which are indicative of higher plant input. Aromatic diterpenoid fraction comprises of simonellite and retene. These compounds are also indicative of higher plants, particularly conifer source which had been a predominant flora during the Cretaceous time.

  2. Fossils and Fossil Climate: The Case for Equable Continental Interiors in the Eocene

    Science.gov (United States)

    Wing, Scott L.; Greenwood, David R.

    1993-08-01

    There are many methods for inferring terrestrial palaeoclimates from palaeontological data, including the size and species diversity of ectothermic vertebrates, the locomotor and dental adaptations of mammals, characteristics of leaf shape, size, and epidermis, wood anatomy, and the climatic preferences of nearest living relatives of fossil taxa. Estimates of palaeotemperature have also been based on stable oxygen isotope ratios in shells and bones. Interpretation of any of these data relies in some way on uniformitarian assumptions, although at different levels depending on the method. Most of these methods can be applied to a palaeoclimatic reconstruction for the interior of North America during the early Eocene, which is thought to be the warmest interval of global climate in the Cenozoic. Most of the data indicate warm equable climates with little frost. Rainfall was variable, but strong aridity was local or absent. The inferred palaeoclimate is very different from the present climate of the region and from model simulations for the Eocene. This suggests that models fail to incorporate forcing factors that were present at that time, that they treat the heat regime of continents unrealistically, and/or that model inputs such as sea surface temperature gradients or palaeotopography are incorrect.

  3. Trace fossils of a cyclic chalk-marl succession; the upper Maastrichtian Rørdal Member, Denmark

    DEFF Research Database (Denmark)

    Lauridsen, Bodil Wesenberg; Surlyk, Finn; Bromley, Richard Granville

    2011-01-01

    Trace fossils from an upper Maastrichtian cyclic chalk–marl succession, the Rørdal Member, exposed in the Rørdal quarry, Denmark, are analysed in order to test whether the changes in substrate lithology exerted any control over the ichnodiversity, tiering complexity, and density of the infauna....... Ichnofabric A is found only in chalk samples and shows a poor preservation of trace fossils, whereas ichnofabric C is found in a few chalk and all marl samples and comprises a very dense, diverse and well preserved ichnofauna representing a high tiering complexity. Ichnofabric B represents an intermediate...... situation between ichnofabrics A and C and occurs in chalk samples immediately adjacent to marl beds. The observed changes in ichnofabrics between chalk and marl are related to the amount of clay in the samples and the differences in the occurrence of trace fossils are interpreted as due to differences...

  4. Parameter Estimation of Fossil Oysters from High Resolution 3D Point Cloud and Image Data

    Science.gov (United States)

    Djuricic, Ana; Harzhauser, Mathias; Dorninger, Peter; Nothegger, Clemens; Mandic, Oleg; Székely, Balázs; Molnár, Gábor; Pfeifer, Norbert

    2014-05-01

    A unique fossil oyster reef was excavated at Stetten in Lower Austria, which is also the highlight of the geo-edutainment park 'Fossilienwelt Weinviertel'. It provides the rare opportunity to study the Early Miocene flora and fauna of the Central Paratethys Sea. The site presents the world's largest fossil oyster biostrome formed about 16.5 million years ago in a tropical estuary of the Korneuburg Basin. About 15,000 up to 80-cm-long shells of Crassostrea gryphoides cover a 400 m2 large area. Our project 'Smart-Geology for the World's largest fossil oyster reef' combines methods of photogrammetry, geology and paleontology to document, evaluate and quantify the shell bed. This interdisciplinary approach will be applied to test hypotheses on the genesis of the taphocenosis (e.g.: tsunami versus major storm) and to reconstruct pre- and post-event processes. Hence, we are focusing on using visualization technologies from photogrammetry in geology and paleontology in order to develop new methods for automatic and objective evaluation of 3D point clouds. These will be studied on the basis of a very dense surface reconstruction of the oyster reef. 'Smart Geology', as extension of the classic discipline, exploits massive data, automatic interpretation, and visualization. Photogrammetry provides the tools for surface acquisition and objective, automated interpretation. We also want to stress the economic aspect of using automatic shape detection in paleontology, which saves manpower and increases efficiency during the monitoring and evaluation process. Currently, there are many well known algorithms for 3D shape detection of certain objects. We are using dense 3D laser scanning data from an instrument utilizing the phase shift measuring principle, which provides accurate geometrical basis < 3 mm. However, the situation is difficult in this multiple object scenario where more than 15,000 complete or fragmentary parts of an object with random orientation are found. The goal

  5. The First Occurrence in the Fossil Record of an Aquatic Avian Twig-Nest with Phoenicopteriformes Eggs: Evolutionary Implication

    OpenAIRE

    Gerald Grellet-Tinner; Xabier Murelaga; Juan C Larrasoaña; Silveira, Luis F.; Maitane Olivares; Ortega, Luis A.; Trimby, Patrick W.; Ana Pascual

    2012-01-01

    14 p. Background: We describe the first occurrence in the fossil record of an aquatic avian twig-nest with five eggs in situ (Early Miocene Tudela Formation, Ebro Basin, Spain). Extensive outcrops of this formation reveal autochthonous avian osteological and oological fossils that represent a single taxon identified as a basal phoenicopterid. Although the eggshell structure is definitively phoenicopterid, the characteristics of both the nest and the eggs are similar to those of modern greb...

  6. A revision of the fossil genus Miocepphus and other Miocene Alcidae (Aves: Charadriiformes) of the Western North Atlantic Ocean

    OpenAIRE

    Wijnker, T.G.; Olson, S. L.

    2009-01-01

    This study reviews and describes all known fossils of Alcidae from the Miocene of the western North Atlantic. Because the majority of alcid fossils recovered from Miocene sediments are allied with the genus Miocepphus Wetmore, 1940, the genus is revised here. Three new species of Miocepphus are described: Miocepphus bohaskai and Miocepphus blowi from the Early to Late Miocene, and Miocepphus mergulellus of uncertain Neogene age but probably Miocene. A new genus and species, Pseudocepphus tere...

  7. Thermally Altered Silurian Cyanobacterial Mats: A Key to Earth's Oldest Fossils

    Science.gov (United States)

    Kazmierczak, Józef; Kremer, Barbara

    2009-10-01

    Diagenetic changes in thermally altered cyanobacterial mats from early Silurian black radiolarian cherts of southwestern Poland (Bardzkie Montains, Sudetes) have been studied. These early diagenetically silicified mats are composed of variously degraded remains of benthic microbes that resemble some modern chroococcalean and pleurocapsalean cyanobacteria. Two modes of degradational processes have been recognized in the studied mats: (i) early postmortem biodegradation and (ii) late diagenetic thermal or thermobaric degradation. The latter led to partial transformation of the fossilized organic remnants of cyanobacterial sheaths and capsules, which resulted in the formation of objects morphologically distant from the original microbiota but preserved features that allow for their identification as bona fide biogenic structures. Some of these thermally generated Silurian fossils are highly similar to the controversial microfossil-like carbonaceous structures described from the Early Archean Apex Chert of Australia. This similarity opens a promising way for credible recognition of remnants of cyanobacteria and similar microbiota in other thermally metamorphosed Archean sedimentary rocks

  8. Using extant taxa to inform studies of fossil footprints

    Science.gov (United States)

    Falkingham, Peter; Gatesy, Stephen

    2016-04-01

    Attempting to use the fossilized footprints of extinct animals to study their palaeobiology and palaeoecology is notoriously difficult. The inconvenient extinction of the trackmaker makes direct correlation between footprints and foot far from straightforward. However, footprints are the only direct evidence of vertebrate motion recorded in the fossil record, and are potentially a source of data on palaeobiology that cannot be obtained from osteological remains alone. Our interests lie in recovering information about the movements of dinosaurs from their tracks. In particular, the Hitchcock collection of early Jurassic tracks held at the Beneski Museum of Natural History, Amherst, provide a rare look into the 3D form of tracks at and below the surface the animal walked on. Breaking naturally along laminations into 'track books', the specimens present sediment deformation at multiple levels, and in doing so record more of the foot's motion than a single surface might. In order to utilize this rich information source to study the now extinct trackmakers, the process of track formation must be understood at a fundamental level; the interaction of the moving foot and compliant substrate. We used bi-planar X-ray techniques (X-ray Reconstruction of Moving Morphology) to record the limb and foot motions of a Guineafowl traversing both granular and cohesive substrates. This data was supplemented with photogrammetric records of the resultant track surfaces, as well as the motion of metal beads within the sediment, to provide a full experimental dataset of foot and footprint formation. The physical experimental data was used to generate computer simulations of the process using high performance computing and the Discrete Element Method. The resultant simulations showed excellent congruence with reality, and enabled visualization within the sediment volume, and throughout the track-forming process. This physical and virtual experimental set-up has provided major insight into

  9. Fossil jawless fish from China foreshadows early jawed vertebrate anatomy.

    Science.gov (United States)

    Gai, Zhikun; Donoghue, Philip C J; Zhu, Min; Janvier, Philippe; Stampanoni, Marco

    2011-08-17

    Most living vertebrates are jawed vertebrates (gnathostomes), and the living jawless vertebrates (cyclostomes), hagfishes and lampreys, provide scarce information about the profound reorganization of the vertebrate skull during the evolutionary origin of jaws. The extinct bony jawless vertebrates, or 'ostracoderms', are regarded as precursors of jawed vertebrates and provide insight into this formative episode in vertebrate evolution. Here, using synchrotron radiation X-ray tomography, we describe the cranial anatomy of galeaspids, a 435-370-million-year-old 'ostracoderm' group from China and Vietnam. The paired nasal sacs of galeaspids are located anterolaterally in the braincase, and the hypophyseal duct opens anteriorly towards the oral cavity. These three structures (the paired nasal sacs and the hypophyseal duct) were thus already independent of each other, like in gnathostomes and unlike in cyclostomes and osteostracans (another 'ostracoderm' group), and therefore have the condition that current developmental models regard as prerequisites for the development of jaws. This indicates that the reorganization of vertebrate cranial anatomy was not driven deterministically by the evolutionary origin of jaws but occurred stepwise, ultimately allowing the rostral growth of ectomesenchyme that now characterizes gnathostome head development.

  10. Segue 1: An unevolved fossil galaxy from the early universe

    Energy Technology Data Exchange (ETDEWEB)

    Frebel, Anna [Kavli Institute for Astrophysics and Space Research and Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Simon, Joshua D. [Observatories of the Carnegie Institution of Washington, Pasadena, CA 91101 (United States); Kirby, Evan N. [Center for Galaxy Evolution, Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States)

    2014-05-01

    We present Magellan/MIKE and Keck/HIRES high-resolution spectra of six red giant stars in the dwarf galaxy Segue 1. Including one additional Segue 1 star observed by Norris et al., high-resolution spectra have now been obtained for every red giant in Segue 1. Remarkably, three of these seven stars have metallicities below [Fe/H] = –3.5, suggesting that Segue 1 is the least chemically evolved galaxy known. We confirm previous medium-resolution analyses demonstrating that Segue 1 stars span a metallicity range of more than 2 dex, from [Fe/H] = –1.4 to [Fe/H] = –3.8. All of the Segue 1 stars are α-enhanced, with [α/Fe] ∼ 0.5. High α-element abundances are typical for metal-poor stars, but in every previously studied galaxy [α/Fe] declines for more metal-rich stars, which is typically interpreted as iron enrichment from supernova Ia. The absence of this signature in Segue 1 indicates that it was enriched exclusively by massive stars. Other light element abundance ratios in Segue 1, including carbon enhancement in the three most metal-poor stars, closely resemble those of metal-poor halo stars. Finally, we classify the most metal-rich star as a CH star given its large overabundances of carbon and s-process elements. The other six stars show remarkably low neutron-capture element abundances of [Sr/H] < –4.9 and [Ba/H] < –4.2, which are comparable to the lowest levels ever detected in halo stars. This suggests minimal neutron-capture enrichment, perhaps limited to a single r-process or weak s-process synthesizing event. Altogether, the chemical abundances of Segue 1 indicate no substantial chemical evolution, supporting the idea that it may be a surviving first galaxy that experienced only one burst of star formation.

  11. On The Nature of Fossil Galaxy Groups

    CERN Document Server

    La Barbera, F; De la Rosa, I G; Sorrentino, G; Gal, R R; Kohl-Moreira, J L

    2009-01-01

    We present a new sample of 25 fossil groups (FGs) at z < 0.1, along with a control sample of seventeen bright ellipticals located in non-fossil systems. Both the global properties of FGs (e.g. X-ray luminosity) as well as the photometric properties (i.e. isophotal shape parameter, a4) and spectroscopic parameters (e.g. the alpha-enhancement) of their first-ranked ellipticals are consistent with those of the control sample. This result favors a scenario where FGs are not a distinct class of systems, but rather a common phase in the life of galaxy groups. We also find no evidence for an evolutionary sequence explaining the formation of galaxies in fossil systems through the merging of galaxies in compact groups.

  12. Recent synchronous radiation of a living fossil.

    Science.gov (United States)

    Nagalingum, N S; Marshall, C R; Quental, T B; Rai, H S; Little, D P; Mathews, S

    2011-11-11

    Modern survivors of previously more diverse lineages are regarded as living fossils, particularly when characterized by morphological stasis. Cycads are often cited as a classic example, reaching their greatest diversity during the Jurassic-Cretaceous (199.6 to 65.5 million years ago) then dwindling to their present diversity of ~300 species as flowering plants rose to dominance. Using fossil-calibrated molecular phylogenies, we show that cycads underwent a near synchronous global rediversification beginning in the late Miocene, followed by a slowdown toward the Recent. Although the cycad lineage is ancient, our timetrees indicate that living cycad species are not much older than ~12 million years. These data reject the hypothesized role of dinosaurs in generating extant diversity and the designation of today's cycad species as living fossils.

  13. Cerium anomaly at microscale in fossils.

    Science.gov (United States)

    Gueriau, Pierre; Mocuta, Cristian; Bertrand, Loïc

    2015-09-01

    Patterns in rare earth element (REE) concentrations are essential instruments to assess geochemical processes in Earth and environmental sciences. Excursions in the "cerium anomaly" are widely used to inform on past redox conditions in sediments. This proxy resources to the specificity of cerium to adopt both the +III and +IV oxidation states, while most rare earths are purely trivalent and share very similar reactivity and transport properties. In practical terms, the level of cerium anomaly is established through elemental point quantification and profiling. All these models rely on a supposed homogeneity of the cerium oxidation state within the samples. However, this has never been demonstrated, whereas the cerium concentration can significantly vary within a sample, as shown for fossils, which would vastly complicate interpretation of REE patterns. Here, we report direct micrometric mapping of Ce speciation through synchrotron X-ray absorption spectroscopy and production of local rare earth patterns in paleontological fossil tissues through X-ray fluorescence mapping. The sensitivity of the approach is demonstrated on well-preserved fishes and crustaceans from the Late Cretaceous (ca. 95 million years (Myr) old). The presence of Ce under the +IV form within the fossil tissues is attributed to slightly oxidative local conditions of burial and agrees well with the limited negative cerium anomaly observed in REE patterns. The [Ce(IV)]/[Ce(tot)] ratio appears remarkably stable at the microscale within each fossil and is similar between fossils from the locality. Speciation maps were obtained from an original combination of synchrotron microbeam X-ray fluorescence, absorption spectroscopy, and diffraction, together with light and electron microscopy. This work also highlights the need for more systematic studies of cerium geochemistry at the microscale in paleontological contexts, in particular across fossil histologies.

  14. Hybrid Test Bed of Wind Electric Generator with Photovoltaic Panels

    Directory of Open Access Journals (Sweden)

    G.D.Anbarasi Jebaselvi

    2014-03-01

    Full Text Available Driven by the increasing costs of power production and decreasing fossil fuel reserves with the addition of global environmental concerns, renewable energy is now becoming significant fraction of total electricity production in the world. Advancements in the field of wind electric generator technology and power electronics help to achieve rapid progress in hybrid power system which mainly involves wind, solar and diesel energy with a good battery back-up. Here the discussion brings about the installation of real time test bed with a small electric generator and dynamic solar panels with battery backups.

  15. Geomechanics of bedded salt

    Energy Technology Data Exchange (ETDEWEB)

    Serata, S.; Milnor, S.W.

    1979-06-08

    Creep data from the literature search is reinterpreted by SGI, resulting in a better understanding of the temperature and stress state dependence of the octahedral creep rate and the octahedral shear strength. The concept of a transition strength between the elastic and the plastic states is in agreement with the data. The elastic and rheological properties of salt are described, and a set of constitutive equations is presented. The dependence of material properties on parameters such as temperature is considered. Findings on the permeability of salt are summarized, and the in-situ behavior of openings in bedded salt is described based on extensive engineering experience. A stress measuring system utilizing a finite element computer code is discussed. Geological factors affecting the stability of salt openings are considered, and the Stress Control Technique for designing stable openings in bedded salt formations is explained.

  16. First early hominin from central Africa (Ishango, Democratic Republic of Congo.

    Directory of Open Access Journals (Sweden)

    Isabelle Crevecoeur

    Full Text Available Despite uncontested evidence for fossils belonging to the early hominin genus Australopithecus in East Africa from at least 4.2 million years ago (Ma, and from Chad by 3.5 Ma, thus far there has been no convincing evidence of Australopithecus, Paranthropus or early Homo from the western (Albertine branch of the Rift Valley. Here we report the discovery of an isolated upper molar (#Ish25 from the Western Rift Valley site of Ishango in Central Africa in a derived context, overlying beds dated to between ca. 2.6 to 2.0 Ma. We used µCT imaging to compare its external and internal macro-morphology to upper molars of australopiths, and fossil and recent Homo. We show that the size and shape of the enamel-dentine junction (EDJ surface discriminate between Plio-Pleistocene and post-Lower Pleistocene hominins, and that the Ishango molar clusters with australopiths and early Homo from East and southern Africa. A reassessment of the archaeological context of the specimen is consistent with the morphological evidence and suggest that early hominins were occupying this region by at least 2 Ma.

  17. Virtual Test Bed

    Science.gov (United States)

    2016-06-07

    project is to develop a benchmark system for evaluating models for predicting the characteristics of ocean wind waves. SCIENTIFIC OBJECTIVES A...transformation-scale models (i.e. models which treat the physics of waves propagating from offshore areas into the coastline). Each phase is further divided...to be assembled within the virtual test bed. Wind fields for running these tests will be obtained from Oceanweather, Inc. from a separate ONR

  18. Microbial Fossils Detected in Desert Varnish

    Science.gov (United States)

    Flood, B. E.; Allen, C.; Longazo, T.

    2003-01-01

    Mars Global Surveyor Thermal Emission Spectrometer data indicate regions with significant levels of hematite (_Fe2O3). Fe-oxides, like hematite, can form as aqueous mineral precipitates and as such may preserve microscopic fossils or other biosignatures. Several potential terrestrial analogues to martian hematite like hydrothermal vents have preserved microfossils. Microbial fossilization in Fe-oxides is often a function of biomineralization. For example, goethite (FeO2H) encrustation of fungal mycelia from the mid-Tertiary preserved fungal morphologies such that their genera could be determined.

  19. Insect diversity in the fossil record

    Science.gov (United States)

    Labandeira, C. C.; Sepkoski, J. J. Jr; Sepkoski JJ, J. r. (Principal Investigator)

    1993-01-01

    Insects possess a surprisingly extensive fossil record. Compilation of the geochronologic ranges of insect families demonstrates that their diversity exceeds that of preserved vertebrate tetrapods through 91 percent of their evolutionary history. The great diversity of insects was achieved not by high origination rates but rather by low extinction rates comparable to the low rates of slowly evolving marine invertebrate groups. The great radiation of modern insects began 245 million years ago and was not accelerated by the expansion of angiosperms during the Cretaceous period. The basic trophic machinery of insects was in place nearly 100 million years before angiosperms appeared in the fossil record.

  20. Dinosaur Footprint Fossils Discovered in Xinjiang

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ Recently,a Chinese-German science fieldwork investigation team,composed of staff from the SinoGerman Paleontology and Geography Joint Lab and the Xinjiang Geological Work Station,announced that they discovered a batch of dinosaur footprint fossils in the dessert 20 kilometers to the east of Shanshan County in the Turpan Basin,Xinjiang Uyghur Autonomous Region.These fossils spread around an area of 100 square meters and scientists believed that these footprints were left behind by carnivore dinosaurs.This major discovery has been published in Global Geology,an English journal published by the NorthEast Asia Geology Center.

  1. Fossils, Genes and The Origin of Organs

    Energy Technology Data Exchange (ETDEWEB)

    Shubin, Neil (University of Chicago)

    2011-04-20

    A toolkit of experimental and comparative biology can be applied to understand the great transformations in the history of life. Expeditionary paleontology can be used to target key nodes of the tree of life for which new fossils can provide insights into major morphological transformations. These fossils often have intermediate conditions that allow extant creatures to be compared in new ways. The tools of developmental genetics can then be used to explore these new comparisons to understand the genetic basis for macroevolutionary change. These different approaches can be used to predict new discoveries and this is only possible because of the empirical content of the tree of life.

  2. New fossil caddisfly from Middle Jurassic of Daohugou, Inner Mongolia, China (Trichoptera: Philopotamidae)

    Institute of Scientific and Technical Information of China (English)

    Meixia Wang; Yunyun Zhao; Dong Ren

    2009-01-01

    A new genus and new species, Juraphilopotamus lubricus gen. et sp. nov., from the Middle Jurassic Jiulongshan Formation of Daohugou, Inner Mongolia, China, is described and illustrated. It may be the first record of the family Philopotamidae in China, extending the geographic distribution of this family. A detailed description and illustration of the specimen along with a brief review of the fossil Philopotamidae are given. A proposal on dispersion and migration of Philopotamidae and problems of the paleoenvironment of the Daohugou beds are discussed.

  3. New fossil mayflies (Insecta: Ephemeroptera) from the Middle Jurassic of Daohugou, Inner Mongolia, China

    Institute of Scientific and Technical Information of China (English)

    Jian-Dong Huang; Dong Ren; Nina D. Sinitshenkova; Chung-Kun Shih

    2008-01-01

    Jurassonurus amoenus, a new genus and species of Siphlonuridae s. l. is described from the Middle Jurassic Jiulongshan Formation of the Daohugou Village, Shantou Township, Ningcheng County, Inner Mongolia, China. The new species is established by more than 20 imago and subimago specimens in relatively good condition. Detailed description and illustration of the specimens along with a review of fossil Siphlonuridae s.l. are given. Comparing with two known dominant nymph species Fuyous gregarious Zhang and Kluge, 2007 and Shantous lacustri Zhang and Kluge, 2007 from the same locality, we could not find any relationship among them. The new species is another dominant species in Daohugou beds.

  4. Fossilized nuclei and chromosomes reveal 180 million years of genomic stasis in royal ferns.

    Science.gov (United States)

    Bomfleur, Benjamin; McLoughlin, Stephen; Vajda, Vivi

    2014-03-21

    Rapidly permineralized fossils can provide exceptional insights into the evolution of life over geological time. Here, we present an exquisitely preserved, calcified stem of a royal fern (Osmundaceae) from Early Jurassic lahar deposits of Sweden in which authigenic mineral precipitation from hydrothermal brines occurred so rapidly that it preserved cytoplasm, cytosol granules, nuclei, and even chromosomes in various stages of cell division. Morphometric parameters of interphase nuclei match those of extant Osmundaceae, indicating that the genome size of these reputed "living fossils" has remained unchanged over at least 180 million years-a paramount example of evolutionary stasis.

  5. THE NUSPLINGEN LITHOGRAPHIC LIMESTONE - A "FOSSIL LAGERSTAETTE" OF LATE KIMMERIDGIAN AGE FROM THE SWABIAN ALB (GERMANY

    Directory of Open Access Journals (Sweden)

    GERD DIETL

    2004-03-01

    Full Text Available A short overview is given on the actual excavations within a fossiliferous lithographic limestone site near Nusplingen (western Swabian Alb, SW Germany. In contrast to the better known Early Tithonian Solnhofen Lithographic Limestone, it is much richer in fossils and 0.5 my older (Late Kimmeridgian, Beckeri Zone, Ulmense Subzone. Many of the fossils exhibit an excellent preservation, sometimes even of the organic matter. More than 7.000 specimens have been recorded belonging to almost 300 taxa (plants, microfossils, invertebrates, ichnofossils, and vertebrates.

  6. The Westphalian D fossil lepidodendrid forest at Table Head, Sydney Basin, Nova Scotia: Sedimentology, paleoecology and floral response to changing edaphic conditions

    Science.gov (United States)

    Calder, J.H.; Gibling, M.R.; Eble, C.F.; Scott, A.C.; MacNeil, D.J.

    1996-01-01

    Strata of Westphalian D age on the western coast of the Sydney Basin expose a fossil forest of approximately 30 lepidodendrid trees within one of several clastic splits of the Harbour Seam. A mutidisciplinary approach was employed to interpret the origins of the coal bed, the depositional history of the site and the response of the fossil forest to changing edaphic conditions. The megaspore and miospore records indicate that the mire vegetation was dominated by arboreous lycopsids, especially Paralycopodites, with subdominant tree ferns. Petrographic, palynological and geochemical evidence suggest that the Harbour coal bed at Table Head originated as a rheotrophic (cf. planar) mire (eutric histosol). The mire forest is interpreted to have been engulfed by prograding distributary-channel sediments; sparse protist assemblages are suggestive of a freshwater delta-plain lake environment occasionally in contact with brackish waters. Lepidodendrids persisted as site colonizers of clastic substrates even after burial of the rheotrophic peatland and influenced the morphology of deposited sediment, but apparently were unable to colonize distributary channels. Equivocal taxonomic data (compression fossils) show the fossil forest to have been composed of both monocarpic (Lepidodendron) and polycarpic (Diaphorodendron, Paralycopodites, ?Sigillaria) lycopsids, genera recorded in the palynology of the uppermost ply of the underlying coal bed. Comparatively rare within the clastic beds of the fossil forest, however, is the stem compression of Paralycopodites, whose dispersed megapores and miospores dominate the underlying coal bed. Tree diameter data recorded equivalent to breast height indicate a forest of mixed age. These data would appear to suggest that some lepidodendrids employing a polycarpic reproductive strategy were better able to cross the ecological barrier imposed between peat and clastic substrates. Foliar compressions indicate that an understory or stand of

  7. Granulation in Miniaturised Fluid Bed Using Electrostatic Atomisation

    OpenAIRE

    Kivikero, Niina

    2010-01-01

    The development of a new drug is extremely expensive and the development process is very slow, up to 15 years. Especially the early formulation development phase is a challenge for the pharmaceutical industry, as the amount of a new active pharmaceutical ingredient may only be a few grams. A small amount of drug should be used to produce as much data as rapidly possible. In this thesis, a small scale fluid bed device (Multipart Microscale Fluid bed powder Processor, MMFP) with electrosta...

  8. Accuracy of Trained Canines for Detecting Bed Bugs (Hemiptera: Cimicidae).

    Science.gov (United States)

    Cooper, Richard; Wang, Changlu; Singh, Narinderpal

    2014-12-01

    Detection of low-level bed bug, Cimex lectularius L. (Hemiptera: Cimicidae), infestations is essential for early intervention, confirming eradication of infestations, and reducing the spread of bed bugs. Despite the importance of detection, few effective tools and methods exist for detecting low numbers of bed bugs. Scent dogs were developed as a tool for detecting bed bugs in recent years. However, there are no data demonstrating the reliability of trained canines under natural field conditions. We evaluated the accuracy of 11 canine detection teams in naturally infested apartments. All handlers believed their dogs could detect infestations at a very high rate (≥95%). In three separate experiments, the mean (min, max) detection rate was 44 (10-100)% and mean false-positive rate was 15 (0-57)%. The false-positive rate was positively correlated with the detection rate. The probability of a bed bug infestation being detected by trained canines was not associated with the level of bed bug infestations. Four canine detection teams evaluated on multiple days were inconsistent in their ability to detect bed bugs and exhibited significant variance in accuracy of detection between inspections on different days. There was no significant relationship between the team's experience or certification status of teams and the detection rates. These data suggest that more research is needed to understand factors affecting the accuracy of canine teams for bed bug detection in naturally infested apartments. © 2014 Entomological Society of America.

  9. New observations on the Middle Fork Eel River coal-bearing beds, Mendocino County, California, USA

    Energy Technology Data Exchange (ETDEWEB)

    Bartley, Russell H. [Mendocino County Museum, 400 East Commercial Street, Willits, CA 95490 (United States); Bartley, Sylvia E. [Noyo Hill House, 28953 Highway 20, Fort Bragg, CA 95437 (United States); Springer, David J. [College of the Redwoods-Mendocino Coast, 1211 Del Mar Drive, Fort Bragg, CA 95437 (United States); Erwin, Diane M. [Museum of Paleontology, 1101 Valley Life Sciences Building, University of California, Berkeley, CA 94720 (United States)

    2010-08-01

    Mid-19th century reports of ''immense'' coal outcrops in the Middle Fork Eel River (MFER) drainage near Round Valley in California's northern Coast Ranges fueled the early geological interest in this area, with mine development the primary focus of many studies. It was not until Samuel G. Clark's 1940 ''Geology of the Covelo District, Mendocino County, California,'' that the coal was placed in its regional geologic context and assigned to the Miocene, a determination that relied primarily on a Desmostylus hesperus molar found in shale overlying the coal and an associated equivocal, though Miocene-compatible, marine molluscan fauna. Our investigation of the MFER coal-bearing beds has provided new data from foraminifera, marine mollusks, fish remains, and the first reported fossil plants, which as a whole support Clark's Miocene age assignment. We also present an updated stratigraphy proposing under modern-day stratigraphic protocols that the informal name Sand Bank beds (SBb) be used in place of the Temblor Formation to refer to the SBb coal-bearing fluvial-marine unit. Analysis of the SBb stratigraphy and sedimentology reveals the presence of a fluvial system that flowed from a distal upland region southward toward the paleocoast of California. An abundant diverse palynoflora containing lycophytes, ferns, conifers, and mesic, thermophillic herbaceous and woody angiosperms indicates the drainage flowed through a coastal swampy forested bottomland and estuarine environment before emptying into a coastal basin. Presence of Taxodium-like wood, foliage, pollen, and other ''hydrophiles'' suggests the MFER coal was a local mire buried by the progradation of the SBb fluvial system during a regressive phase, an interpretation to be tested with future field work and detailed compositional analysis of the coal. (author)

  10. Phase-Plane Invariant Analysis of Pressure Fluctuations in Fluidized Beds

    Institute of Scientific and Technical Information of China (English)

    WANG Xiaoliang; HE Rong; Toshiyuki Suda; Junichi Sato

    2007-01-01

    Partial agglomeration is a major problem in fluidized beds. A chaotic analytical method based on the phase-plane invariant of the pressure fluctuations in the fluidized beds has been used to warn of agglomeration at an early stage. Cold tests (no combustion) and hot tests (combustion) in fluidized beds show that the phase-plane invariant of the pressure fluctuations can distinguish the dynamic behavior of fluidized beds with different flow rates in cold tests. With combustion, when the flow rate was kept constant, agglomeration was detected very early by looking at the phase-plane invariant. The phase-plane invariant can be used to distinguish changes in fluidized beds due to changes in the flow rate, agglomeration, or various other factors. Therefore, this reliable agglomeration early warning system can be used for better control of circulating fluidized beds.

  11. Taphonomy of the fossil insects of the middle Eocene Kishenehn Formation

    Directory of Open Access Journals (Sweden)

    Dale E. Greenwalt

    2015-12-01

    Full Text Available The lacustrine oil shales of the Coal Creek Member of the Kishenehn Formation in northwestern Montana comprise a relatively unstudied middle Eocene fossil insect locality. Herein, we detail the stratigraphic position of the fossiliferous unit, describe the insect fauna of the Coal Creek locality and document its bias towards very small but remarkably pre-served insects. In addition, the depositional environment is examined and the mineral constituents of the laminations that comprise the varves of the Kishenehn oil shale are defined. Fifteen orders of insects have been recorded with the majority of all insects identified as aquatic with the families Chironomidae (Diptera and Corixidae (Hemiptera dominant. The presence of small aquatic insects, many of which are immature, the intact nature of >90% of the fossil insects and the presence of Daphnia ephippia, all indicate that the depositional environment was the shallow margin of a large freshwater lake. The fossil insects occur within fossilized microbial mat layers that comprise the bedding planes of the oil shale. Unlike the fossiliferous shales of the Florissant and Okanagan Highlands, the mats are not a product of diatomaceous algae nor are diatom frustules a component of the sediments or the varve structure. Instead, the varves are composed of very fine eolian siliciclastic silt grains overlaid with non-diatomaceous, possibly cyanobacteria-derived microbial mats which contain distinct traces of polyaromatic hydrocarbons. A distinct third layer composed of essentially pure calcite is present in the shale of some exposures and is presumably derived from the seasonal warming-induced precipitation of carbonate from the lake’s waters. The Coal Creek locality presents a unique opportunity to study both very small middle Eocene insects not often preserved as compression fossils in most Konservat-Lagerstätte and the processes that led to their preservation.

  12. Spatial Vegetation Data for Hagerman Fossil Beds National Monument Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — High resolution vegetation polygons mapped by the National Park Service. To produce the digital map, 1:12,000-scale true color digital ortho-imagery acquired in 2004...

  13. Field Plot and Accuracy Assessment Points for Hagerman Fossil Beds National Monument Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — Accuracy Assessment, Observation and Plot Points. Plot points were created from the GPS coordinates recorded at the center of each plot to map their distribution and...

  14. Spatial Vegetation Data for Florissant Fossil Beds National Monument Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — The vegetation units on this map were determined through the stereoscopic interpretation of aerial photographs supported by field sampling and ecological analysis....

  15. Accuracy Assessment Points for Florissant Fossil Beds National Monument Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — The accuracy assessment field work was performed in July - August, 2001 to verify the accuracy of the vegetation communities spatial data developed by the USGS-NPS...

  16. Fossil fuels supplies modeling and research

    Energy Technology Data Exchange (ETDEWEB)

    Leiby, P.N.

    1996-06-01

    The fossil fuel supplies modeling and research effort focuses on models for US Strategic Petroleum Reserve (SPR) planning and management. Topics covered included new SPR oil valuation models, updating models for SPR risk analysis, and fill-draw planning. Another task in this program area is the development of advanced computational tools for three-dimensional seismic analysis.

  17. Fossil Energy Materials Program conference proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Judkins, R.R. (comp.)

    1987-08-01

    The US Department of Energy Office of Fossil Energy has recognized the need for materials research and development to assure the adequacy of materials of construction for advanced fossil energy systems. The principal responsibility for identifying needed materials research and for establishing a program to address these needs resides within the Office of Technical Coordination. That office has established the Advanced Research and Technology Development (AR and TD) Fossil Energy Materials Program to fulfill that responsibility. In addition to the AR and TD Materials Program, which is designed to address in a generic way the materials needs of fossil energy systems, specific materials support activities are also sponsored by the various line organizations such as the Office of Coal Gasification. A conference was held at Oak Ridge, Tennessee on May 19-21, 1987, to present and discuss the results of program activities during the past year. The conference program was organized in accordance with the research thrust areas we have established. These research thrust areas include structural ceramics (particularly fiber-reinforced ceramic composites), corrosion and erosion, and alloy development and mechanical properties. Eighty-six people attended the conference. Papers have been entered individually into EDB and ERA. (LTN)

  18. On the fossil record of the Gekkota.

    Science.gov (United States)

    Daza, Juan D; Bauer, Aaron M; Snively, Eric D

    2014-03-01

    Gekkota is often interpreted as sister to all remaining squamates, exclusive of dibamids, or as sister to Autarchoglossa. It is the only diverse lineage of primarily nocturnal lizards and includes some of the smallest amniotes. The skeleton of geckos has often been interpreted as paedomorphic and/or "primitive" but these lizards also display a wide range of structural specializations of the postcranium, including modifications associated with both scansorial locomotion and limb reduction. Although the concept of "Gekkota" has been variously applied by different authors, we here apply a rigorous apomorphy based definition, recent advances in gekkotan morphology and phylogenetics, and diverse comparative material to provide a comprehensive assessment of 28 known pre-Quaternary geckos, updating the last such review, published three decades ago. Fossils evaluated include both sedimentary fossils and amber-embedded specimens. Known Cretaceous geckos are exclusively Asian and exhibit character combinations not seen in any living forms. Cenozoic gekkotans derive from sites around the world, although Europe is especially well represented. Paleogene geckos are largely known from disarticulated remains and show similarities to Sphaerodactylidae and Diplodactylidae, although resemblances may be plesiomorphic in some cases. Many Neogene gekkotans are referable to living families or even genera, but their geographic occurrences are often extralimital to those of modern groups, as is consistent with paleoclimatic conditions. The phylogenetic placement of fossil gekkotans has important repercusions for timetree calibration, but at present only a small number of fossils can be confidently assigned to even family level groupings, limiting their utility in this regard.

  19. The Fascinating Story of Fossil Fuels

    Science.gov (United States)

    Asimov, Isaac

    1973-01-01

    How this energy source was created, its meaning to mankind, our drastically reduced supply, and why we cannot wait for nature to make more are considered. Today fossil fuels supply 96 percent of the energy used but we must find alternate energy options if we are to combat the energy crisis. (BL)

  20. The Fascinating Story of Fossil Fuels

    Science.gov (United States)

    Asimov, Isaac

    1973-01-01

    How this energy source was created, its meaning to mankind, our drastically reduced supply, and why we cannot wait for nature to make more are considered. Today fossil fuels supply 96 percent of the energy used but we must find alternate energy options if we are to combat the energy crisis. (BL)

  1. Fossil Hunting: Intracluster Stars in Virgo

    NARCIS (Netherlands)

    Murphy, Eric; Bridge, Carrie; Desai, Vandana; Kenney, Jeffrey; Krick, Jessica; Surace, Jason; van Gorkom, Jacqueline

    2009-01-01

    In dense clusters, galaxy interactions and mergers play a significant role in galaxy evolution. During these interactions, tidal forces can lead to the ejection of stars from their parent galaxies; these stars are a fossil record of environmentally-driven galaxy evolution. We propose to map the intr

  2. Giant fossil coelacanths of the Late Cretaceous in the eastern United States

    Science.gov (United States)

    Schwimmer, David R.; Stewart, J. D.; Dent Williams, G.

    1994-06-01

    Remains of giant fossil coelacanth fish are relatively common in Upper Cretaceous strata (late Santonian to early Campanian age) in Alabama and Georgia. These are penecontemporaneous with the youngest reported fossil coelacanths from any global location and ˜135 m.y. younger than the last coelacanth fish reported from North America. A coelacanth coronoid fragment from New Jersey, apparently from the same taxon, is of latest Campanian or Maastrichtian age and is the youngest known definite coelacanth fossil. The species reconstructs to 3.5 m, which is as large as any known coelacanth. The name Megalocoelacanthus dobiei is proposed for this new coelacanth, which is also the last known member of the Glade that includes the extant Latimeria.

  3. Transitional fossil earwigs - a missing link in Dermaptera evolution

    Directory of Open Access Journals (Sweden)

    Ren Dong

    2010-11-01

    Full Text Available Abstract Background The Dermaptera belongs to a group of winged insects of uncertain relationship within Polyneoptera, which has expanded anal region and adds numerous anal veins in the hind wing. Evolutional history and origin of Dermaptera have been in contention. Results In this paper, we report two new fossil earwigs in a new family of Bellodermatidae fam. nov. The fossils were collected from the Jiulongshan Formation (Middle Jurassic in Inner Mongolia, northeast China. This new family, characterized by an unexpected combination of primitive and derived characters, is bridging the missing link between suborders of Archidermaptera and Eodermaptera. Phylogenetic analyses support the new family to be a new clade at the base of previously defined Eodermaptera and to be a stem group of (Eodermaptera+Neodermaptera. Conclusion Evolutional history and origin of Dermaptera have been in contention, with dramatically different viewpoints by contemporary authors. It is suggested that the oldest Dermaptera might possibly be traced back to the Late Triassic-Early Jurassic and they had divided into Archidermaptera and (Eodermaptera+Neodermaptera in the Middle Jurassic.

  4. Reciprocal evolution of the cerebellum and neocortex in fossil humans.

    Science.gov (United States)

    Weaver, Anne H

    2005-03-08

    Human brain evolution involved both neurological reorganization and an increase in overall brain volume relative to body mass. It is generally difficult to draw functional inferences about the timing and nature of brain reorganization, given that superficial brain morphology recorded on fossil endocasts is functionally ambiguous. However, the cerebellum, housed in the clearly delineated posterior cranial fossa, is functionally and ontologically discrete. The cerebellum is reciprocally connected to each of 14 neocortical regions important to human cognitive evolution. Cerebellar volume varies significantly relative to overall brain volume among mammalian orders, as well as within the primate order. There is also significant diachronic variation among fossil human taxa. In the australopithecines and early members of the genus Homo, the cerebral hemispheres were large in proportion to the cerebellum, compared with other hominoids. This trend continued in Middle and Late Pleistocene humans, including Neandertals and Cro-Magnon 1, who have the largest cerebral hemispheres relative to cerebellum volume of any primates, including earlier and Holocene humans. In recent humans, however, the pattern is reversed; the cerebellum is larger with respect to the rest of the brain (and, conversely, the cerebral hemispheres are smaller with respect to the cerebellum) than in Late Pleistocene humans. The cerebellum and cerebral hemispheres appear to have evolved reciprocally. Cerebellar development in Holocene humans may have provided greater computational efficiency for coping with an increasingly complex cultural and conceptual environment.

  5. Understanding and predicting bed humidity in fluidized bed granulation.

    Science.gov (United States)

    Hu, Xinhui; Cunningham, John; Winstead, Denita

    2008-04-01

    Bed humidity is a critical parameter that needs to be controlled in a fluidized bed granulation to ensure reliability. To predict and control the bed humidity during the fluidized bed granulation process, a simple model based on the mass conservation of moisture was developed. The moisture mass balance model quantitatively simulates the effects of spray rate, binder solution concentration, airflow rate, inlet air temperature, and dew point on the bed humidity. The model was validated by a series of granulations performed in different scale granulators including Glatt GPCG-1, GPCG-15, and GPCG-60. Good agreement was observed between the theoretical prediction and the measured loss on drying (LOD). The model developed in the current work enables us to choose the appropriate parameters for the fluidized bed granulation and can be used as a valuable tool in process scaling-up.

  6. New fossils of Australopithecus anamensis from Kanapoi, West Turkana, Kenya (2003-2008).

    Science.gov (United States)

    Ward, C V; Manthi, F K; Plavcan, J M

    2013-11-01

    Renewed fieldwork from 2003 through 2008 at the Australopithecus anamensis type-site of Kanapoi, Kenya, yielded nine new fossils attributable to this species. These fossils all date to between 4.195 and 4.108 million years ago. Most were recovered from the lower fluvial sequence at the site, with one from the lacustrine sequence deltaic sands that overlie the lower fluvial deposits but are still below the Kanapoi Tuff. The new specimens include a partial edentulous mandible, partial maxillary dentition, two partial mandibular dentitions, and five isolated teeth. The new Kanapoi hominin fossils increase the sample known from the earliest Australopithecus, and provide new insights into morphology within this taxon. They support the distinctiveness of the early A. anamensis fossils relative to earlier hominins and to the later Australopithecus afarensis. The new fossils do not appreciably extend the range of observed variation in A. anamensis from Kanapoi, with the exception of some slightly larger molars, and a canine tooth root that is the largest in the hominin fossil record. All of the Kanapoi hominins share a distinctive morphology of the canine-premolar complex, typical early hominin low canine crowns but with mesiodistally longer honing teeth than seen in A. afarensis, and large, probably dimorphic, canine tooth roots. The new Kanapoi specimens support the observation that canine crown height, morphology, root size and dimorphism were not altered from a primitive ape-like condition as part of a single event in human evolution, and that there may have been an adaptive difference in canine function between A. anamensis and A. afarensis.

  7. Coal Bed Methane Primer

    Energy Technology Data Exchange (ETDEWEB)

    Dan Arthur; Bruce Langhus; Jon Seekins

    2005-05-25

    During the second half of the 1990's Coal Bed Methane (CBM) production increased dramatically nationwide to represent a significant new source of income and natural gas for many independent and established producers. Matching these soaring production rates during this period was a heightened public awareness of environmental concerns. These concerns left unexplained and under-addressed have created a significant growth in public involvement generating literally thousands of unfocused project comments for various regional NEPA efforts resulting in the delayed development of public and fee lands. The accelerating interest in CBM development coupled to the growth in public involvement has prompted the conceptualization of this project for the development of a CBM Primer. The Primer is designed to serve as a summary document, which introduces and encapsulates information pertinent to the development of Coal Bed Methane (CBM), including focused discussions of coal deposits, methane as a natural formed gas, split mineral estates, development techniques, operational issues, producing methods, applicable regulatory frameworks, land and resource management, mitigation measures, preparation of project plans, data availability, Indian Trust issues and relevant environmental technologies. An important aspect of gaining access to federal, state, tribal, or fee lands involves education of a broad array of stakeholders, including land and mineral owners, regulators, conservationists, tribal governments, special interest groups, and numerous others that could be impacted by the development of coal bed methane. Perhaps the most crucial aspect of successfully developing CBM resources is stakeholder education. Currently, an inconsistent picture of CBM exists. There is a significant lack of understanding on the parts of nearly all stakeholders, including industry, government, special interest groups, and land owners. It is envisioned the Primer would being used by a variety of

  8. Bed Rest Muscular Atrophy

    Science.gov (United States)

    Greenleaf, John E.

    2000-01-01

    A major debilitating response from prolonged bed rest (BR) is muscle atrophy, defined as a "decrease in size of a part of tissue after full development has been attained: a wasting away of tissue as from disuse, old age, injury or disease". Part of the complicated mechanism for the dizziness, increased body instability, and exaggerated gait in patients who arise immediately after BR may be a result of not only foot pain, but also of muscular atrophy and associated reduction in lower limb strength. Also, there seems to be a close association between muscle atrophy and bone atrophy. A discussion of many facets of the total BR homeostatic syndrome has been published. The old adage that use determines form which promotes function of bone (Wolff's law) also applies to those people exposed to prolonged BR (without exercise training) in whom muscle atrophy is a consistent finding. An extreme case involved a 16-year-old boy who was ordered to bed by his mother in 1932: after 50 years in bed he had "a lily-white frame with limbs as thin as the legs of a ladder-back chair". These findings emphasize the close relationship between muscle atrophy and bone atrophy. In addition to loss of muscle mass during deconditioning, there is a significant loss of muscle strength and a decrease in protein synthesis. Because the decreases in force (strength) are proportionately greater than those in fiber size or muscle cross-sectional area, other contributory factors must be involved; muscle fiber dehydration may be important.

  9. Bed Rest Muscular Atrophy

    Science.gov (United States)

    Greenleaf, John E.

    2000-01-01

    A major debilitating response from prolonged bed rest (BR) is muscle atrophy, defined as a "decrease in size of a part of tissue after full development has been attained: a wasting away of tissue as from disuse, old age, injury or disease". Part of the complicated mechanism for the dizziness, increased body instability, and exaggerated gait in patients who arise immediately after BR may be a result of not only foot pain, but also of muscular atrophy and associated reduction in lower limb strength. Also, there seems to be a close association between muscle atrophy and bone atrophy. A discussion of many facets of the total BR homeostatic syndrome has been published. The old adage that use determines form which promotes function of bone (Wolff's law) also applies to those people exposed to prolonged BR (without exercise training) in whom muscle atrophy is a consistent finding. An extreme case involved a 16-year-old boy who was ordered to bed by his mother in 1932: after 50 years in bed he had "a lily-white frame with limbs as thin as the legs of a ladder-back chair". These findings emphasize the close relationship between muscle atrophy and bone atrophy. In addition to loss of muscle mass during deconditioning, there is a significant loss of muscle strength and a decrease in protein synthesis. Because the decreases in force (strength) are proportionately greater than those in fiber size or muscle cross-sectional area, other contributory factors must be involved; muscle fiber dehydration may be important.

  10. Racing for the Bed

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    No one knows when the people ofMacheng City began to employthe marriage custom of racingfor the bed, once a custom unique to theTujia ethnic minority. It is said that at the end of awedding, bride and bridegroom enter thebridal chamber together and race for thebed. The one who is the first to sit on thebed will be the master of the new familyIt sounds unreasonable, but quite anumber of people believe in it.Therefore, on the wedding night, manybrides and bridegrooms try their best to

  11. Biparticle fluidized bed reactor

    Science.gov (United States)

    Scott, C.D.

    1993-12-14

    A fluidized bed reactor system which utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase is described. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary particulate phase, continuously introduced and removed in either cocurrent or countercurrent mode, acts in a secondary role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Introduction and removal of the sorbent phase is accomplished through the use of feed screw mechanisms and multivane slurry valves. 3 figures.

  12. 浙江宁海早上新世枫香树属和栎属化石木及其古环境意义%Identification of the early Early Pliocene fossil woods from Ninghai in Zhejiang Province and its palaeoenvironmental implications

    Institute of Scientific and Technical Information of China (English)

    程业明; 扆铁梅; 李承森

    2013-01-01

    Fossil woods were collected from the Lower Pliocene Shengxian Group near Daoshiqiao village of Chayuan Town, Ninghai County of Zhejiang Province. The specimens were examined microscopically to determine taxonomic affinities. Two fossil taxa were identified based on anatomical characters. One wood is Liquidambar hisauchi of Hamamelidaceae. Its combined characteristics include distinct growth ring, diffuse-porous wood, scalariform perforation plate with 10-23 bars, helical thickenings only in the end of vessels, vessel diameters between 50-100 μm and ray width between 1-3 seriates. The other one is Quercus shimakurae of Fagaceae. Its combined characteristics include very distinct growth ring, ring-porous wood, solitary pore, vessel-ray pitting in paliform , simple perforation, axial parenchyma diffuse-in-aggregate and banded apotracheal, uni-seriate or very wide rays. Results of the palynomor-ph assemblage research indicate that the vegetation of this period was subtropical evergreen and deciduous broad-leaved mixed forest and Liquidambar and Quercus were the dominant.%对发现于浙江省宁海县茶园乡道士桥村附近的上新统嵊县群中的多个化石木材料进行了解剖研究,并对其分类和系统位置进行了讨论.根据解剖特征鉴定出2种化石木.一种为久内枫香树(Liquidambar hisauchi),属于金缕梅科枫香树属,其组合特征为:生长轮明显;散孔材;梯状穿孔板具横隔10 ~ 23条;螺纹加厚仅出现在导管末端;导管直径在50~ 100 μm之间;射线宽1~3列.另一种为岛仓栎(Quercus shimakurae),属于壳斗科栎属,其组合特征为:生长轮极明显;环孔材;单管孔;晚材管孔火焰状径列;早材管孔直径最大达300 μm,明显比晚材管孔大;单穿孔;轴向薄壁组织星散聚合状和离管带状;射线具单列和极宽2种类型.本研究从大化石角度进一步证明栎属和枫香树属为当时植被的重要组成成分.

  13. Inflation Fossils in Cosmic Structure

    Science.gov (United States)

    Kamionkowski, Marc

    The agreement of the predictions of inflation with increasingly precise cosmic microwave background (CMB) and large-scale-structure (LSS) data is remarkable. The notion that such a simple early-Universe scenario, based on still-mysterious ultra-high-energy physics, can explain such a wealth of precise data is simply amazing. An active ongoing program of research is afoot to seek the CMB polarization signatures of inflationary gravitational waves and measure the primordial bispectrum in order to learn about inflation. Still, there is far more that can be done to probe inflationary physics, and no stone should be left unturned in this quest. Here we propose a multi-component program of theoretical research that includes model building, new CMB/LSS tests, a potentially powerful new survey strategy, and the investigation of a new observational avenue for large-scale structure. We propose to broaden the circle of ideas to empirically probe inflation. To begin, the hemispherical power asymmetry seen in WMAP and Planck is truly striking. While it may simply be an unusual statistical fluke, a more tantalizing possibility is that it is a remnant of the pre-inflationary Universe. We propose to develop and study several physical models for this asymmetry and work out other testable predictions of these models. Only by pursuing other signatures of whatever new physics may be responsible for this asymmetry will we be able to infer if it is truly a window to new physics. We also plan to develop departures from statistical isotropy (SI) as a test of inflationary models. We have recently shown that single-field slow-roll inflation generically predicts a quadrupolar departure from SI in primordial perturbations, albeit a very small one. The power quadrupole is expected, however, to be significantly larger in more general inflationary models. We propose to calculate these power quadrupoles so that new constraints to the power quadrupole from CMB and LSS data can be applied to test

  14. [Raman spectra of fossil dinosaurs from different regions].

    Science.gov (United States)

    Yang, Qun; Wang, Yi-lin

    2007-12-01

    Raman microscopic spectra in the higher wave number region were obtained from 7 fossil dinosaurs specimens from different regions. The specimens of fossil dinosaurs are different parts of bone. The Raman spectra of fossil dinosaurs indicate the high similarity among peak positions of different fossil dinosaurs; but important differences exist in the spectral peak figures. In the wave number region of 1000-1800 cm(-1) the Raman spectra of the same bone part fossils from different regions are very similar, example similarities between spectra of Lufeing backbone head and Yua nmou backbone head; Lufeng limb bone and Wuding limb bone. There are relations between the same bone part spectra of different fossil dinosaurs. The characteristic does not relate to regions. Raman spectra of fossil dinosaurs cannot be used to distinguish fossil source, although the part of bone can be used as an indicator to narrow the range of possible geographical origins.

  15. Fossils and palaeontological distributions of Macaranga and Mallotus (Euphorbiaceae)

    NARCIS (Netherlands)

    Nucete, M.; van Konijnenburg-van Cittert, J.H.A.; van Welzen, P.C.

    2012-01-01

    The correct identification of described plant fossils from the sister genera Macaranga and Mallotus (Euphorbiaceae) needs to be confirmed in order to correctly date their phylogeny and map their palaeontological distributions. Previous identifications of fossil specimens often appear to be

  16. The controversial “Cambrian” fossils of the Vindhyan are real but more than a billion years older

    Science.gov (United States)

    Bengtson, Stefan; Belivanova, Veneta; Rasmussen, Birger; Whitehouse, Martin

    2009-01-01

    The age of the Vindhyan sedimentary basin in central India is controversial, because geochronology indicating early Proterozoic ages clashes with reports of Cambrian fossils. We present here an integrated paleontologic–geochronologic investigation to resolve this conundrum. New sampling of Lower Vindhyan phosphoritic stromatolitic dolomites from the northern flank of the Vindhyans confirms the presence of fossils most closely resembling those found elsewhere in Cambrian deposits: annulated tubes, embryo-like globules with polygonal surface pattern, and filamentous and coccoidal microbial fabrics similar to Girvanella and Renalcis. None of the fossils, however, can be ascribed to uniquely Cambrian or Ediacaran taxa. Indeed, the embryo-like globules are not interpreted as fossils at all but as former gas bubbles trapped in mucus-rich cyanobacterial mats. Direct dating of the same fossiliferous phosphorite yielded a Pb–Pb isochron of 1,650 ± 89 (2σ) million years ago, confirming the Paleoproterozoic age of the fossils. New U–Pb geochronology of zircons from tuffaceous mudrocks in the Lower Vindhyan Porcellanite Formation on the southern flank of the Vindhyans give comparable ages. The Vindhyan phosphorites provide a window of 3-dimensionally preserved Paleoproterozoic fossils resembling filamentous and coccoidal cyanobacteria and filamentous eukaryotic algae, as well as problematic forms. Like Neoproterozoic phosphorites a billion years later, the Vindhyan deposits offer important new insights into the nature and diversity of life, and in particular, the early evolution of multicellular eukaryotes. PMID:19416859

  17. NEW MATERIAL OF FOSSIL PLANTS FROM THE EARLY CRETACEOUS MULING FORMATION OF THE JIXI BASIN, EASTERN HEILONGJIANG PROVINCE, CHINA%黑龙江省东部鸡西盆地早白垩世穆棱组植物化石新材料

    Institute of Scientific and Technical Information of China (English)

    杨小菊

    2003-01-01

    The Early Cretaceous flora from the Muling Formation of the Jixi Basin, Heilongjiang Province, Northeast China comprises 38 species, so far as known, belonging to 31 genera of high plants, of which 23 species of 22 genera are described here. The angiospermous leaves Asiatefolium elegans and Dicotylophyllum sp. are found in the Muling Formation for the first time. Cuticles of Tyrmia sp., Nilssoniopteris sp., Ginkgoites cf. sibirica, Sphenobaiera sp., Elatocladus manchurica are studied with scanning electron microscope (SEM). The flora is mainly composed of leptosporangiate ferns and gymnosperms. Most of them occurred in the Lower Cretaceous. The geological age of the Muling Formation and its flora may be Barremian and probably middle Barremian-early Aptian. No representatives of gymnosperms with needle-like leaves have been found in this flora. The occurrence of abundant tropical- or subtropical-type ferns implies a warm and humid climate dominating over the area. On the other hand, some deciduous gymnosperms including Ginkgoales, and the presence of growth rings in the fossil secondary wood, indicate seasonal changes. Paleophytogeographically, the flora belongs to the Early Cretaceous Siberian or Canada-Siberian province.%系统描述了最近采集的穆棱组植物化石22属23种,其中的两种被子植物叶化石均为具原始被子植物叶特征的小型叶, 在该植物群中尚属首次发现.运用扫描电镜(SEM)等方法对其中的Tyrmia sp.,Nilssoniopteris sp.,Ginkgoites cf.sibirica,Sphenobaiera sp.,Elatocladus manchurica等化石的叶角质层进行了研究.据已有的资料统计,穆棱组迄今已知有化石植物31属38种.该植物群以真蕨类占据绝对优势,裸子植物也相当丰富,其中的大多数种类主要见于早白垩世,穆棱组的地质时代应属早白垩世巴列姆期或巴列姆-阿普梯早期.植物组合中以丰富的热带及亚热带型植物为主要特点,未发现针叶类型的植物,说明早白垩世

  18. Quaternary fossil fauna from the Luangwa Valley, Zambia.

    OpenAIRE

    Bishop, LC; Barham, LS; Ditchfield, P.; Elton, S; Harcourt-Smith, WH; Dawkins, P

    2016-01-01

    This paper describes a large collection of Quaternary fossil fauna from the Luangwa rift valley, Zambia. Stone Age artefacts have been recovered from stratified fluvial contexts, but no in situ fossil fauna have yet been recovered. We report on 500 fossil specimens collected from the surface of point bars exposed seasonally along the banks of the main Luangwa river channel. We used non-destructive x-ray fluorescence analysis of the fossils' chemical signatures to determine whether they derive...

  19. A survey of paleozoic microbial fossils in chert

    Science.gov (United States)

    Tobin, Kenneth J.

    2004-06-01

    Non-acritarch, microbial fossils from Paleozoic marine cherts exhibit generally poor preservation with rare exceptional preservation. Microbial microfossils were discovered in 11 out of 17 stromatolitic and non-stromatolitic Paleozoic units containing replacement cherts from the continental United States. Many microfossils likely have a cyanobacterial affinity having both coccoid and filamentous morphotypes. Examined units range in age from Middle Cambrian to Late Permian and were deposited in peritidal, open shelf, and basinal settings; all of which have preserved microbial assemblages. Cherts from the examined units generally formed during early diagenesis and the quality of microbial preservation does not seem to have changed during the Paleozoic, which is a period that experienced significant secular changes in the mode of marine silica formation.

  20. The fossil trade: paying a price for human origins

    DEFF Research Database (Denmark)

    2012-01-01

    Fossils have been traded for centuries. Over the past two hundred years the market has developed into an organised enterprise with fossils serving multiple functions as scientific objects of study, collectors’ items and investments. Finding fossils, digging them up or purchasing them, transporting...

  1. Probe into the Internal Mechanism of Interlanguage Fossilization

    Science.gov (United States)

    Huang, Qian

    2009-01-01

    Interlanguage fossilization is normal for second language acquisition. It is also a hotspot for studies on theory of foreign language acquisition. Many reasons cause the interlanguage fossilization. This paper probes into the internal mechanism of interlanguage fossilization from five aspects, namely the physiological aspect, the psychological…

  2. Age and context of the oldest known hominin fossils from Flores.

    Science.gov (United States)

    Brumm, Adam; van den Bergh, Gerrit D; Storey, Michael; Kurniawan, Iwan; Alloway, Brent V; Setiawan, Ruly; Setiyabudi, Erick; Grün, Rainer; Moore, Mark W; Yurnaldi, Dida; Puspaningrum, Mika R; Wibowo, Unggul P; Insani, Halmi; Sutisna, Indra; Westgate, John A; Pearce, Nick J G; Duval, Mathieu; Meijer, Hanneke J M; Aziz, Fachroel; Sutikna, Thomas; van der Kaars, Sander; Flude, Stephanie; Morwood, Michael J

    2016-06-09

    Recent excavations at the early Middle Pleistocene site of Mata Menge in the So'a Basin of central Flores, Indonesia, have yielded hominin fossils attributed to a population ancestral to Late Pleistocene Homo floresiensis. Here we describe the age and context of the Mata Menge hominin specimens and associated archaeological findings. The fluvial sandstone layer from which the in situ fossils were excavated in 2014 was deposited in a small valley stream around 700 thousand years ago, as indicated by (40)Ar/(39)Ar and fission track dates on stratigraphically bracketing volcanic ash and pyroclastic density current deposits, in combination with coupled uranium-series and electron spin resonance dating of fossil teeth. Palaeoenvironmental data indicate a relatively dry climate in the So'a Basin during the early Middle Pleistocene, while various lines of evidence suggest the hominins inhabited a savannah-like open grassland habitat with a wetland component. The hominin fossils occur alongside the remains of an insular fauna and a simple stone technology that is markedly similar to that associated with Late Pleistocene H. floresiensis.

  3. Himalayan fossils of the oldest known pantherine establish ancient origin of big cats.

    Science.gov (United States)

    Tseng, Z Jack; Wang, Xiaoming; Slater, Graham J; Takeuchi, Gary T; Li, Qiang; Liu, Juan; Xie, Guangpu

    2014-01-07

    Pantherine felids ('big cats') include the largest living cats, apex predators in their respective ecosystems. They are also the earliest diverging living cat lineage, and thus are important for understanding the evolution of all subsequent felid groups. Although the oldest pantherine fossils occur in Africa, molecular phylogenies point to Asia as their region of origin. This paradox cannot be reconciled using current knowledge, mainly because early big cat fossils are exceedingly rare and fragmentary. Here, we report the discovery of a fossil pantherine from the Tibetan Himalaya, with an age of Late Miocene-Early Pliocene, replacing African records as the oldest pantherine. A 'total evidence' phylogenetic analysis of pantherines indicates that the new cat is closely related to the snow leopard and exhibits intermediate characteristics on the evolutionary line to the largest cats. Historical biogeographic models provide robust support for the Asian origin of pantherines. The combined analyses indicate that 75% of the divergence events in the pantherine lineage extended back to the Miocene, up to 7 Myr earlier than previously estimated. The deeper evolutionary origin of big cats revealed by the new fossils and analyses indicate a close association between Tibetan Plateau uplift and diversification of the earliest living cats.

  4. Himalayan fossils of the oldest known pantherine establish ancient origin of big cats

    Science.gov (United States)

    Tseng, Z. Jack; Wang, Xiaoming; Slater, Graham J.; Takeuchi, Gary T.; Li, Qiang; Liu, Juan; Xie, Guangpu

    2014-01-01

    Pantherine felids (‘big cats’) include the largest living cats, apex predators in their respective ecosystems. They are also the earliest diverging living cat lineage, and thus are important for understanding the evolution of all subsequent felid groups. Although the oldest pantherine fossils occur in Africa, molecular phylogenies point to Asia as their region of origin. This paradox cannot be reconciled using current knowledge, mainly because early big cat fossils are exceedingly rare and fragmentary. Here, we report the discovery of a fossil pantherine from the Tibetan Himalaya, with an age of Late Miocene–Early Pliocene, replacing African records as the oldest pantherine. A ‘total evidence’ phylogenetic analysis of pantherines indicates that the new cat is closely related to the snow leopard and exhibits intermediate characteristics on the evolutionary line to the largest cats. Historical biogeographic models provide robust support for the Asian origin of pantherines. The combined analyses indicate that 75% of the divergence events in the pantherine lineage extended back to the Miocene, up to 7 Myr earlier than previously estimated. The deeper evolutionary origin of big cats revealed by the new fossils and analyses indicate a close association between Tibetan Plateau uplift and diversification of the earliest living cats. PMID:24225466

  5. Enamel ultrastructure in fossil cetaceans (Cetacea: Archaeoceti and Odontoceti.

    Directory of Open Access Journals (Sweden)

    Carolina Loch

    Full Text Available The transition from terrestrial ancestry to a fully pelagic life profoundly altered the body systems of cetaceans, with extreme morphological changes in the skull and feeding apparatus. The Oligocene Epoch was a crucial time in the evolution of cetaceans when the ancestors of modern whales and dolphins (Neoceti underwent major diversification, but details of dental structure and evolution are poorly known for the archaeocete-neocete transition. We report the morphology of teeth and ultrastructure of enamel in archaeocetes, and fossil platanistoids and delphinoids, ranging from late Oligocene (Waitaki Valley, New Zealand to Pliocene (Caldera, Chile. Teeth were embedded in epoxy resin, sectioned in cross and longitudinal planes, polished, etched, and coated with gold palladium for scanning electron microscopy (SEM observation. SEM images showed that in archaeocetes, squalodontids and Prosqualodon (taxa with heterodont and nonpolydont/limited polydont teeth, the inner enamel was organized in Hunter-Schreger bands (HSB with an outer layer of radial enamel. This is a common pattern in most large-bodied mammals and it is regarded as a biomechanical adaptation related to food processing and crack resistance. Fossil Otekaikea sp. and delphinoids, which were polydont and homodont, showed a simpler structure, with inner radial and outer prismless enamel. Radial enamel is regarded as more wear-resistant and has been retained in several mammalian taxa in which opposing tooth surfaces slide over each other. These observations suggest that the transition from a heterodont and nonpolydont/limited polydont dentition in archaeocetes and early odontocetes, to homodont and polydont teeth in crownward odontocetes, was also linked to a marked simplification in the enamel Schmelzmuster. These patterns probably reflect functional shifts in food processing from shear-and-mastication in archaeocetes and early odontocetes, to pierce-and-grasp occlusion in crownward

  6. Enamel ultrastructure in fossil cetaceans (Cetacea: Archaeoceti and Odontoceti).

    Science.gov (United States)

    Loch, Carolina; Kieser, Jules A; Fordyce, R Ewan

    2015-01-01

    The transition from terrestrial ancestry to a fully pelagic life profoundly altered the body systems of cetaceans, with extreme morphological changes in the skull and feeding apparatus. The Oligocene Epoch was a crucial time in the evolution of cetaceans when the ancestors of modern whales and dolphins (Neoceti) underwent major diversification, but details of dental structure and evolution are poorly known for the archaeocete-neocete transition. We report the morphology of teeth and ultrastructure of enamel in archaeocetes, and fossil platanistoids and delphinoids, ranging from late Oligocene (Waitaki Valley, New Zealand) to Pliocene (Caldera, Chile). Teeth were embedded in epoxy resin, sectioned in cross and longitudinal planes, polished, etched, and coated with gold palladium for scanning electron microscopy (SEM) observation. SEM images showed that in archaeocetes, squalodontids and Prosqualodon (taxa with heterodont and nonpolydont/limited polydont teeth), the inner enamel was organized in Hunter-Schreger bands (HSB) with an outer layer of radial enamel. This is a common pattern in most large-bodied mammals and it is regarded as a biomechanical adaptation related to food processing and crack resistance. Fossil Otekaikea sp. and delphinoids, which were polydont and homodont, showed a simpler structure, with inner radial and outer prismless enamel. Radial enamel is regarded as more wear-resistant and has been retained in several mammalian taxa in which opposing tooth surfaces slide over each other. These observations suggest that the transition from a heterodont and nonpolydont/limited polydont dentition in archaeocetes and early odontocetes, to homodont and polydont teeth in crownward odontocetes, was also linked to a marked simplification in the enamel Schmelzmuster. These patterns probably reflect functional shifts in food processing from shear-and-mastication in archaeocetes and early odontocetes, to pierce-and-grasp occlusion in crownward odontocetes, with

  7. Body mass estimates of hominin fossils and the evolution of human body size.

    Science.gov (United States)

    Grabowski, Mark; Hatala, Kevin G; Jungers, William L; Richmond, Brian G

    2015-08-01

    Body size directly influences an animal's place in the natural world, including its energy requirements, home range size, relative brain size, locomotion, diet, life history, and behavior. Thus, an understanding of the biology of extinct organisms, including species in our own lineage, requires accurate estimates of body size. Since the last major review of hominin body size based on postcranial morphology over 20 years ago, new fossils have been discovered, species attributions have been clarified, and methods improved. Here, we present the most comprehensive and thoroughly vetted set of individual fossil hominin body mass predictions to date, and estimation equations based on a large (n = 220) sample of modern humans of known body masses. We also present species averages based exclusively on fossils with reliable taxonomic attributions, estimates of species averages by sex, and a metric for levels of sexual dimorphism. Finally, we identify individual traits that appear to be the most reliable for mass estimation for each fossil species, for use when only one measurement is available for a fossil. Our results show that many early hominins were generally smaller-bodied than previously thought, an outcome likely due to larger estimates in previous studies resulting from the use of large-bodied modern human reference samples. Current evidence indicates that modern human-like large size first appeared by at least 3-3.5 Ma in some Australopithecus afarensis individuals. Our results challenge an evolutionary model arguing that body size increased from Australopithecus to early Homo. Instead, we show that there is no reliable evidence that the body size of non-erectus early Homo differed from that of australopiths, and confirm that Homo erectus evolved larger average body size than earlier hominins. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Phosphatized Punctatus with mouthparts and its embryo fossils from the Lower Cambrian of Ningqiang, south Shaanxi, China

    Institute of Scientific and Technical Information of China (English)

    LIU Yunhuan; LI Yong; SHAO Tiequan; ZHU Zhixin; YU Bo; WANG Zhuo; ZHANG Wanqian; LI Rongxi

    2007-01-01

    The appearance of coelenterates marks the real beginning ofmetazoan evolution. It therefore has a prominent position in the origin and evolutionary history of organisms,and is also a pivotal question of evolutionary biology.Punctatus is an extinct, ancient marine animal from the early stage of the Cambrian explosion, occurring at. The lowermost Cambrian of both Kuanchuanpu (Ningqiang, Shaanxi) and Maidiping (Emei, Sichuan) areas. Punctatus has been studied for many years since the discovery of its fragments. System-atic and phylogenetic analysis has long been limited because of the rarity of complete specimens. In order to improve research into Punctatus, more than ten thousand globular fossils were recovered by means of "Chemistry Retting". On the basis of the study of these globular fossils, a series of Punctatus fossils with cone parts and finely preserved soft-tissue mouthparts and fossilized metazoan embryo were recovered. Through research on characteristics such as shape,modality and structure of these fossils symbiotic with Punctatus emeiensis, the author found many possible embryo fossils including the evidence of gastrula-stage animal fossils.The sequence of fetation might have appeared on the corol-liform oral region of Punctatus emeiensis. A study of the soft tissues, functional morphology and the sequence of embryo fossils shows evidence that Punctatus resembles coelenterate polyps in systematic classification. Perhaps it also represents an ancestor of the coelenterate with an original tentacle. A comparison with the real "tentacle animal" found in the Chengjiang Fauna, shows that the original tentacle is very tiny and its function range is limited. This reveals the primi-tive nature of the animal. Although the original tentacle is so small, it does exist, representing the first big step towards the real flexible tentacle with a strong function from the early evolving tentacle.

  9. Danmarks Største Fossiler

    DEFF Research Database (Denmark)

    Lindow, Bent Erik Kramer; Cuny, Gilles Guy Roger

    2008-01-01

    For 8 millioner år siden myldrede Nordsøen af en mangfoldighed af hajer, hvaler, havskildpadder og sæler, mange flere end i dag. Blandt dem finder man Danmarks største fossiler som er udstillet på Museum Sønderjylland - Naturhistorie og Palæontologi i Gram.......For 8 millioner år siden myldrede Nordsøen af en mangfoldighed af hajer, hvaler, havskildpadder og sæler, mange flere end i dag. Blandt dem finder man Danmarks største fossiler som er udstillet på Museum Sønderjylland - Naturhistorie og Palæontologi i Gram....

  10. Cassini State Transitions with a Fossil Figure

    Science.gov (United States)

    Matsuyama, Isamu; Tuttle Keane, James

    2016-10-01

    The Moon has experienced large obliquity variations during Cassini state transitions which greatly impact tidal heating, and the long-term stability of polar volatiles. It has been known for centuries that the lunar rotational and tidal bulges are much larger than expected. The South Pole-Aitken basin can explain a large fraction of the excess deformation. Accounting for the contribution of this basin (and other large basins), the remaining excess deformation arises due to a fossil figure established when the Moon orbited much closer to Earth than it does today. Previous studies assume that the present, excess deformation is entirely preserved throughout Cassini state transitions. This ignores basin contributions to the excess deformation, and requires an interior with infinite rigidity. We consider Cassini state transition models that take into account basin contributions to the excess deformation, and the effect of finite rigidity on the fossil figure.

  11. Fossil energy waste management. Technology status report

    Energy Technology Data Exchange (ETDEWEB)

    Bossart, S.J.; Newman, D.A.

    1995-02-01

    This report describes the current status and recent accomplishments of the Fossil Energy Waste Management (FE WM) projects sponsored by the Morgantown Energy Technology Center (METC) of the US Department of Energy (DOE). The primary goal of the Waste Management Program is to identify and develop optimal strategies to manage solid by-products from advanced coal technologies for the purpose of ensuring the competitiveness of advanced coal technologies as a future energy source. The projects in the Fossil Energy Waste Management Program are divided into three types of activities: Waste Characterization, Disposal Technologies, and Utilization Technologies. This technology status report includes a discussion on barriers to increased use of coal by-products. Also, the major technical and nontechnical challenges currently being addressed by the FE WM program are discussed. A bibliography of 96 citations and a list of project contacts is included if the reader is interested in obtaining additional information about the FE WM program.

  12. Fossil Biodiversity: Red Noise Plus Signal

    CERN Document Server

    Melott, A L; Melott, Adrian L.; Lieberman, Bruce S.

    2006-01-01

    We have examined the Fourier power spectrum as well as the Hurst exponent of extinction, origination, and total biodiversity in the marine fossil record, using a recently improved geologic timescale. We find all of them strongly inconsistent with past claims of self-similarity as well as inconsistent with random walk behavior. Instead, they are dominated by low-frequency power, with approximate f^-2 power over one decade in frequency. The spectrum turns over at about 10^5 y, lending plausibility to connections with galactic dynamics. Even in the background of this low-frequency dominance, a previously noted 62 My biodiversity cycle stands out with better than 99% confidence above the noise level, accounting for about 35% of the total variance in the fossil biodiversity record.

  13. Diatoms: a fossil fuel of the future.

    Science.gov (United States)

    Levitan, Orly; Dinamarca, Jorge; Hochman, Gal; Falkowski, Paul G

    2014-03-01

    Long-term global climate change, caused by burning petroleum and other fossil fuels, has motivated an urgent need to develop renewable, carbon-neutral, economically viable alternatives to displace petroleum using existing infrastructure. Algal feedstocks are promising candidate replacements as a 'drop-in' fuel. Here, we focus on a specific algal taxon, diatoms, to become the fossil fuel of the future. We summarize past attempts to obtain suitable diatom strains, propose future directions for their genetic manipulation, and offer biotechnological pathways to improve yield. We calculate that the yields obtained by using diatoms as a production platform are theoretically sufficient to satisfy the total oil consumption of the US, using between 3 and 5% of its land area. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Decarbonisation of fossil energy via methane pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Kreysa, G.; Agar, D.W.; Schultz, I. [Technische Univ. Dortmund (Germany)

    2010-12-30

    Despite the rising consumption of energy over the last few decades, the proven reserves of fossil fuels have steadily increased. Additionally, there are potentially tremendous reserves of methane hydrates available, which remain to be exploited. The use of fossil energy sources is thus increasingly being dictated less by supply than by the environmental concerns raised by climate change. In the context of the decarbonisation of the global energy system that this has stimulated, new means must be explored for using methane as energy source. Noncatalytic thermal pyrolysis of methane is proposed here as a promising concept for utilising methane with low to zero carbon dioxide emissions. Following cracking, only the energy content of the hydrogen is used, while the carbon can be stored safely and retrievably in disused coal mines. The thermodynamics and different process engineering concepts for the technical realisation of such a carbon moratorium technology are discussed. The possible contribution of methane pyrolysis to carbon negative geoengineering is also addressed. (orig.)

  15. Geochemical characteristics of fossil Solenites murrayana cuticles from the Jurassic in Lanzhou, northwest China

    Energy Technology Data Exchange (ETDEWEB)

    Sun, B.N.; Yan, D.F.; Xie, S.P.; Shi, Y.J.; Zhang, C.J.; Lin, Z.C. [Lanzhou University, Lanzhou (China)

    2006-07-01

    Through geochemical analysis on cuticles of the Jurassic fossil Solenites murrayuna L. et H. from the Yaojie Coalfield in Lanzhou, northwest China, and by comparison of geochemical features with its nearest living equivalent, Ginkgo biloba, we show that the characteristics of organic matter of the fossil plant cuticles accord with evolutionary features of asphalt in oil formation. The content analysis of organic matter indicates that the geochemistry is equivalent to rotten mud-sapropel humus types from Mesozoic and Cenozoic source rock in China. Some analysis data of organic matter indicate that Solenites murrayana cuticles are in a low mature stage, which coincides with the hydrocarbon generation model of cutinite in coal. Moreover, distribution features of soluble organic matter of cuticles show that fossil plant cuticles have a definite action in forming terrestrial high-wax oil, which has testified the contribution of high plants to waxness. The present study proves that Ginkgophytes abundant in the Jurassic were a high potential plant in the formation of coal-bed hydrocarbon.

  16. Development of a new method for improving load turndown in fluidized bed combustors: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Brown, R.C.

    1988-12-01

    The objective of this research was to investigate a new concept in fluidized bed design that improves load turndown capability. This improvement is accomplished by independently controlling heat transfer and combustion in the combustor. The design consists of two fluidized beds, one central and one annular. The central bed serves as the combustion bed. The annular bed is fluidized separately from the combustion bed and its level of fluidization determine the overall heat transfer rate from the combustion bed to the surrounding water jacket. Early theoretical considerations suggested a load turndown exceeding ten was possible for this design. This research consisted of three major phases: development of a computational model to predict heat transfer in the two-bed combustor, heat transfer measurements in hot-and-cold flow models of the combustor, and combustion tests in an optimally designed combustor. The computation model was useful in selecting the design of the combustor. Annular bed width and particle sizes were chosen with the aid of the model. The heat transfer tests were performed to determine if the existing correlations for fluidized bed heat transfer coefficients were sufficiently accurate for high aspect ratio fluidized beds (such as the annular bed in the combustor). Combustion tests were performed in an optimally designed combustor. Three fuel forms were used: double screened, crushed coal, coal-water-limestone mixtures (CWLM), and coal-limestone briquettes. 18 refs., 30 figs., 8 tabs.

  17. Variability of Bed Drag on Cohesive Beds under Wave Action

    Directory of Open Access Journals (Sweden)

    Ilgar Safak

    2016-04-01

    Full Text Available Drag force at the bed acting on water flow is a major control on water circulation and sediment transport. Bed drag has been thoroughly studied in sandy waters, but less so in muddy coastal waters. The variation of bed drag on a muddy shelf is investigated here using field observations of currents, waves, and sediment concentration collected during moderate wind and wave events. To estimate bottom shear stress and the bed drag coefficient, an indirect empirical method of logarithmic fitting to current velocity profiles (log-law, a bottom boundary layer model for combined wave-current flow, and a direct method that uses turbulent fluctuations of velocity are used. The overestimation by the log-law is significantly reduced by taking turbulence suppression due to sediment-induced stratification into account. The best agreement between the model and the direct estimates is obtained by using a hydraulic roughness of 10 - 4 m in the model. Direct estimate of bed drag on the muddy bed is found to have a decreasing trend with increasing current speed, and is estimated to be around 0.0025 in conditions where wave-induced flow is relatively weak. Bed drag shows an increase (up to fourfold with increasing wave energy. These findings can be used to test the bed drag parameterizations in hydrodynamic and sediment transport models and the skills of these models in predicting flows in muddy environments.

  18. Variability of bed drag on cohesive beds under wave action

    Science.gov (United States)

    Safak, Ilgar

    2016-01-01

    Drag force at the bed acting on water flow is a major control on water circulation and sediment transport. Bed drag has been thoroughly studied in sandy waters, but less so in muddy coastal waters. The variation of bed drag on a muddy shelf is investigated here using field observations of currents, waves, and sediment concentration collected during moderate wind and wave events. To estimate bottom shear stress and the bed drag coefficient, an indirect empirical method of logarithmic fitting to current velocity profiles (log-law), a bottom boundary layer model for combined wave-current flow, and a direct method that uses turbulent fluctuations of velocity are used. The overestimation by the log-law is significantly reduced by taking turbulence suppression due to sediment-induced stratification into account. The best agreement between the model and the direct estimates is obtained by using a hydraulic roughness of 10  m in the model. Direct estimate of bed drag on the muddy bed is found to have a decreasing trend with increasing current speed, and is estimated to be around 0.0025 in conditions where wave-induced flow is relatively weak. Bed drag shows an increase (up to fourfold) with increasing wave energy. These findings can be used to test the bed drag parameterizations in hydrodynamic and sediment transport models and the skills of these models in predicting flows in muddy environments.

  19. Future Fossil Fuel Alternative; DME (A review)

    OpenAIRE

    Erdener, Hülya; Arinan, Ayca; Orman, Sultan

    2016-01-01

    The world energy consumption is steadily growing with the industrial improvements of the developing countries and the readily available fossil fuel reserves lack in fulfilling this energy requirement. The depletion of the easily achievable reserves; gives rise to the concept of oil production from oil shale and tar sands. However, the high cost and the operational difficulties stand as the major drawbacks in front of these technologies. Along with these circumstances, and the environmental co...

  20. Adaptation, plant evolution, and the fossil record

    Science.gov (United States)

    Knoll, A. H.; Niklas, K. J.

    1987-01-01

    The importance of adaptation in determining patterns of evolution has become an important focus of debate in evolutionary biology. As it pertains to paleobotany, the issue is whether or not adaptive evolution mediated by natural selection is sufficient to explain the stratigraphic distributions of taxa and character states observed in the plant fossil record. One means of addressing this question is the functional evaluation of stratigraphic series of plant organs set in the context of paleoenvironmental change and temporal patterns of floral composition within environments. For certain organ systems, quantitative estimates of biophysical performance can be made on the basis of structures preserved in the fossil record. Performance estimates for plants separated in time or space can be compared directly. Implicit in different hypotheses of the forces that shape the evolutionary record (e.g. adaptation, mass extinction, rapid environmental change, chance) are predictions about stratigraphic and paleoenvironmental trends in the efficacy of functional performance. Existing data suggest that following the evolution of a significant structural innovation, adaptation for improved functional performance can be a major determinant of evolutionary changes in plants; however, there are structural and development limits to functional improvement, and once these are reached, the structure in question may no longer figure strongly in selection until and unless a new innovation evolves. The Silurian-Devonian paleobotanical record is consistent with the hypothesis that the succession of lowland floodplain dominants preserved in the fossil record of this interval was determined principally by the repeated evolution of new taxa that rose to ecological importance because of competitive advantages conferred by improved biophysical performance. This does not seem to be equally true for Carboniferous-Jurassic dominants of swamp and lowland floodplain environments. In these cases

  1. The phylogeny of fossil whip spiders.

    Science.gov (United States)

    Garwood, Russell J; Dunlop, Jason A; Knecht, Brian J; Hegna, Thomas A

    2017-04-21

    Arachnids are a highly successful group of land-dwelling arthropods. They are major contributors to modern terrestrial ecosystems, and have a deep evolutionary history. Whip spiders (Arachnida, Amblypygi), are one of the smaller arachnid orders with ca. 190 living species. Here we restudy one of the oldest fossil representatives of the group, Graeophonus anglicus Pocock, 1911 from the Late Carboniferous (Duckmantian, ca. 315 Ma) British Middle Coal Measures of the West Midlands, UK. Using X-ray microtomography, our principal aim was to resolve details of the limbs and mouthparts which would allow us to test whether this fossil belongs in the extant, relict family Paracharontidae; represented today by a single, blind species Paracharon caecus Hansen, 1921. Tomography reveals several novel and significant character states for G. anglicus; most notably in the chelicerae, pedipalps and walking legs. These allowed it to be scored into a phylogenetic analysis together with the recently described Paracharonopsis cambayensis Engel & Grimaldi, 2014 from the Eocene (ca. 52 Ma) Cambay amber, and Kronocharon prendinii Engel & Grimaldi, 2014 from Cretaceous (ca. 99 Ma) Burmese amber. We recovered relationships of the form ((Graeophonus (Paracharonopsis + Paracharon)) + (Charinus (Stygophrynus (Kronocharon (Charon (Musicodamon + Paraphrynus)))))). This tree largely reflects Peter Weygoldt's 1996 classification with its basic split into Paleoamblypygi and Euamblypygi lineages; we were able to score several of his characters for the first time in fossils. Our analysis draws into question the monophyly of the family Charontidae. Our data suggest that Graeophonus is a crown group amblypygid, and falls within a monophyletic Paleoamblypgi clade, but outside the family Paracharontidae (= Paracharonopsis + Paracharon). Our results also suggest a new placement for the Burmese amber genus Kronocharon, a node further down from its original position. Overall, we offer a

  2. The Properties of Fossil Groups of Galaxies

    CERN Document Server

    Eigenthaler, Paul

    2009-01-01

    Numerical simulations as well as optical and X-ray observations over the last few years have shown that poor groups of galaxies can evolve to what is called a fossil group. Dynamical friction as the driving process leads to the coalescence of individual galaxies in ordinary poor groups leaving behind nothing more than a central, massive elliptical galaxy supposed to contain the merger history of the whole group. Due to merging timescales for less-massive galaxies and gas cooling timescales of the X-ray intragroup medium exceeding a Hubble time, a surrounding faint-galaxy population having survived this galactic cannibalism as well as an extended X-ray halo similar to that found in ordinary groups, is expected. Recent studies suggest that fossil groups are very abundant and could be the progenitors of brightest cluster galaxies (BCGs) in the centers of rich galaxy clusters. However, only a few objects are known to the literature. This article aims to summarize the results of observational fossil group research...

  3. Fossil harvestmen (Arachnida, Opiliones from Bitterfeld amber

    Directory of Open Access Journals (Sweden)

    Jason Dunlop

    2009-07-01

    Full Text Available Fossil harvestmen (Arachnida: Opiliones: Dyspnoi and Eupnoi are described from Bitterfeld amber, Sachsen-Anhalt, Germany deposited in the Museum für Naturkunde, Berlin. The exact age of this amber has been in dispute, but recent work suggests it is youngest Palaeogene (Oligocene: Chattian. Histricostoma tuberculatum (Koch & Berendt, 1854, Caddo dentipalpus (Koch & Berendt, 1854, Dicranopalpus ramiger (Koch & Berendt, 1854 and Leiobunum longipes Menge, 1854 – all of which are also known from Eocene Baltic amber – are reported from Bitterfeld amber for the first time. They support the idea that both ambers sampled a similar terrestrial arthropod fauna: irrespective of any difference in age. Mitostoma gruberi sp. n. and Amilenus deltshevi sp. n. are described as new. One fossil is, in our opinion, morphologically indistinguishable from the extant species Lacinius erinaceus Staręga, 1966 from the Caucuses, and is tentatively assigned to this taxon. The Bitterfeld material thus includes the first fossil record of the extant genera Amilenus Martens, 1969 and Lacinius Thorell, 1876 respectively.

  4. A new phyllopod bed-like assemblage from the Burgess Shale of the Canadian Rockies

    OpenAIRE

    Caron, Jean-Bernard; Gaines, Robert; Aria, Cédric; Mangano, Gabriela; Streng, Michael

    2014-01-01

    Burgess Shale-type fossil assemblages provide the best evidence of the ‘Cambrian explosion’. Here we report the discovery of an extraordinary new soft-bodied fauna from the Burgess Shale. Despite its proximity (ca. 40km) to Walcott’s original locality, the Marble Canyon fossil assemblage is distinct, and offers new insights into the initial diversification of metazoans, their early morphological disparity, and the geographic ranges and longevity of many Cambrian taxa. The arthropod-dominated ...

  5. New fossil ants in French Cretaceous amber (Hymenoptera: Formicidae)

    Science.gov (United States)

    Perrichot, Vincent; Nel, André; Néraudeau, Didier; Lacau, Sébastien; Guyot, Thierry

    2008-02-01

    Recent studies on the ant phylogeny are mainly based on the molecular analyses of extant subfamilies and do not include the extinct, only Cretaceous subfamily Sphecomyrminae. However, the latter is of major importance for ant relationships, as it is considered the most basal subfamily. Therefore, each new discovery of a Mesozoic ant is of high interest for improving our understanding of their early history and basal relationships. In this paper, a new sphecomyrmine ant, allied to the Burmese amber genus Haidomyrmex, is described from mid-Cretaceous amber of France as Haidomyrmodes mammuthus gen. and sp. n. The diagnosis of the tribe Haidomyrmecini is emended based on the new type material, which includes a gyne (alate female) and two incomplete workers. The genus Sphecomyrmodes, hitherto known by a single species from Burmese amber, is also reported and a new species described as S. occidentalis sp. n. after two workers remarkably preserved in a single piece of Early Cenomanian French amber. The new fossils provide additional information on early ant diversity and relationships and demonstrate that the monophyly of the Sphecomyrminae, as currently defined, is still weakly supported.

  6. Fossilized melanosomes and the colour of Cretaceous dinosaurs and birds.

    Science.gov (United States)

    Zhang, Fucheng; Kearns, Stuart L; Orr, Patrick J; Benton, Michael J; Zhou, Zhonghe; Johnson, Diane; Xu, Xing; Wang, Xiaolin

    2010-02-25

    Spectacular fossils from the Early Cretaceous Jehol Group of northeastern China have greatly expanded our knowledge of the diversity and palaeobiology of dinosaurs and early birds, and contributed to our understanding of the origin of birds, of flight, and of feathers. Pennaceous (vaned) feathers and integumentary filaments are preserved in birds and non-avian theropod dinosaurs, but little is known of their microstructure. Here we report that melanosomes (colour-bearing organelles) are not only preserved in the pennaceous feathers of early birds, but also in an identical manner in integumentary filaments of non-avian dinosaurs, thus refuting recent claims that the filaments are partially decayed dermal collagen fibres. Examples of both eumelanosomes and phaeomelanosomes have been identified, and they are often preserved in life position within the structure of partially degraded feathers and filaments. Furthermore, the data here provide empirical evidence for reconstructing the colours and colour patterning of these extinct birds and theropod dinosaurs: for example, the dark-coloured stripes on the tail of the theropod dinosaur Sinosauropteryx can reasonably be inferred to have exhibited chestnut to reddish-brown tones.

  7. Traversing the mountaintop: world fossil fuel production to 2050.

    Science.gov (United States)

    Nehring, Richard

    2009-10-27

    During the past century, fossil fuels--petroleum liquids, natural gas and coal--were the dominant source of world energy production. From 1950 to 2005, fossil fuels provided 85-93% of all energy production. All fossil fuels grew substantially during this period, their combined growth exceeding the increase in world population. This growth, however, was irregular, providing for rapidly growing per capita production from 1950 to 1980, stable per capita production from 1980 to 2000 and rising per capita production again after 2000. During the past half century, growth in fossil fuel production was essentially limited by energy demand. During the next half century, fossil fuel production will be limited primarily by the amount and characteristics of remaining fossil fuel resources. Three possible scenarios--low, medium and high--are developed for the production of each of the fossil fuels to 2050. These scenarios differ primarily by the amount of ultimate resources estimated for each fossil fuel. Total fossil fuel production will continue to grow, but only slowly for the next 15-30 years. The subsequent peak plateau will last for 10-15 years. These production peaks are robust; none of the fossil fuels, even with highly optimistic resource estimates, is projected to keep growing beyond 2050. World fossil fuel production per capita will thus begin an irreversible decline between 2020 and 2030.

  8. Effectiveness of Bed Bug Pesticides

    Science.gov (United States)

    Before EPA allows a bed bug claim on a label, the product must be supported by data showing it will kill bed bugs when applied according to the label. Also consider factors such as extent of infestation, site preparation, and insect life stages.

  9. Bed Bug Laws and Regulations

    Science.gov (United States)

    21 states have some level of regulation with regard to bed bugs. Most of these requirements focus on hotels and landlords or other property managers. The Department of Housing and Urban Development has guidance on controlling bed bugs in public housing.

  10. Oldest fossil flowers of hamamelidaceous affinity, from the Late Cretaceous of New Jersey.

    Science.gov (United States)

    Crepet, W L; Nixon, K C; Friis, E M; Freudenstein, J V

    1992-10-01

    Exceptionally well-preserved staminate inflorescences, pistillate inflorescences, and detached stamens with important phylogenetic and paleoecological implications have been discovered from the Turonian (ca. 88.5-90.4 million years B.P.) Raritan Formation of New Jersey. The fossils have a combination of floral and pollen characters found in various genera of modern entomophilous and anemophilous Hamamelidaceae and anemophilous Platanus (Platanaceae). The floral characters of the fossils, including a sepal cup, staminal tube, and apparently nectariferous staminodes, indicate that this taxon was probably insect pollinated. The juxtaposition of character complexes in an extinct taxon from disparate modern taxa provides an interesting phylogenetic perspective on the origins of Hamamelidaceae and is a striking example of a fossil that is a mosaic of familial level characters relative to modern taxa. Of even broader interest, however, is the occurrence of staminodal nectaries that have structural characters intermediate between the fossil's functional stamens and modern hamamelidaceous petals. This transitional staminode morphology in the context of the other fossil characters suggests a staminodal origin of petals in the hamamelid-rosid lineage. This hypothesis is supported by the apparent staminode position within the fossil flowers where petals are found in modern genera. The character complex of morphologically transitional staminodes, a staminal tube, and sepal cup can be viewed as prehypanthial, lacking only fusion of the staminal tube to the sepal cup. The appearance of the character complex embodied in these flowers during the late mid-Cretaceous may signal the early stages of the relationship between specialized pollinators, such as bees, and the hamamelid-rosid-asterid lineage of angiosperms, arguably one of the most important events in angiosperm radiation.

  11. Major Radiations in the Evolution of Caviid Rodents: Reconciling Fossils, Ghost Lineages, and Relaxed Molecular Clocks

    Science.gov (United States)

    Pérez, María Encarnación; Pol, Diego

    2012-01-01

    Background Caviidae is a diverse group of caviomorph rodents that is broadly distributed in South America and is divided into three highly divergent extant lineages: Caviinae (cavies), Dolichotinae (maras), and Hydrochoerinae (capybaras). The fossil record of Caviidae is only abundant and diverse since the late Miocene. Caviids belongs to Cavioidea sensu stricto (Cavioidea s.s.) that also includes a diverse assemblage of extinct taxa recorded from the late Oligocene to the middle Miocene of South America (“eocardiids”). Results A phylogenetic analysis combining morphological and molecular data is presented here, evaluating the time of diversification of selected nodes based on the calibration of phylogenetic trees with fossil taxa and the use of relaxed molecular clocks. This analysis reveals three major phases of diversification in the evolutionary history of Cavioidea s.s. The first two phases involve two successive radiations of extinct lineages that occurred during the late Oligocene and the early Miocene. The third phase consists of the diversification of Caviidae. The initial split of caviids is dated as middle Miocene by the fossil record. This date falls within the 95% higher probability distribution estimated by the relaxed Bayesian molecular clock, although the mean age estimate ages are 3.5 to 7 Myr older. The initial split of caviids is followed by an obscure period of poor fossil record (refered here as the Mayoan gap) and then by the appearance of highly differentiated modern lineages of caviids, which evidentially occurred at the late Miocene as indicated by both the fossil record and molecular clock estimates. Conclusions The integrated approach used here allowed us identifying the agreements and discrepancies of the fossil record and molecular clock estimates on the timing of the major events in cavioid evolution, revealing evolutionary patterns that would not have been possible to gather using only molecular or paleontological data alone. PMID

  12. Fossil Energy Program semiannual progress report, October 1990--March 1991

    Energy Technology Data Exchange (ETDEWEB)

    Judkins, R.R.

    1992-07-01

    This report covers progress made during the period October 1, 1990, through March 31, 1991, for research and development projects that contribute to the advancement of various fossil energy technologies. Projects on the Fossil Energy Program are supported by the DOE Office of Fossil Energy, the DOE Morgantown Energy Technology Center, the DOE Pittsburgh Energy Technology Center, the DOE Fossil Energy Clean Coal Technology Program, the DOE Office of Basic Energy Sciences, the DOE Fossil Energy Office of Petroleum Reserves, the DOE Fossil Energy Naval Petroleum and Oil Shale Reserves, and the US Agency for International Development. The Fossil, Energy Program organization chart is shown in the appendix. Topics include: alloys, ceramics and composite research and development; corrosion and erosion research; environmental analysis and information systems; coal conversion development; mild gasification product characterization; coal combustion research; strategic petroleum reserve planning and modeling; and coal structure and chemistry.

  13. Distinguishing heat from light in debate over controversial fossils.

    Science.gov (United States)

    Donoghue, Philip C J; Purnell, Mark A

    2009-02-01

    Fossil organisms offer our only direct insight into how the distinctive body plans of extant organisms were assembled. However, realizing the potential evolutionary significance of fossils can be hampered by controversy over their interpretation. Here, as a guide to evaluating palaeontological debates, we outline the process and pitfalls of fossil interpretation. The physical remains of controversial fossils should be reconstructed before interpreting homologies, and choice of interpretative model should be explicit and justified. Extinct taxa lack characters diagnostic of extant clades because the characters had not yet evolved, because of secondary loss, or because they have rotted away. The latter, if not taken into account, will lead to the spurious assignment of fossils to basally branching clades. Conflicting interpretations of fossils can often be resolved by considering all the steps in the process of anatomical analysis and phylogenetic placement, although we must accept that some fossil organisms are simply too incompletely preserved for their evolutionary significance to be realized.

  14. Dinosaur footprints and other ichnofauna from the cretaceous Kem Kem beds of Morocco.

    Science.gov (United States)

    Ibrahim, Nizar; Varricchio, David J; Sereno, Paul C; Wilson, Jeffery A; Wilson, Jeff A; Dutheil, Didier B; Martill, David M; Baidder, Lahssen; Zouhri, Samir

    2014-01-01

    We describe an extensive ichnofossil assemblage from the likely Cenomanian-age 'lower' and 'upper' units of the 'Kem Kem beds' in southeastern Morocco. In the lower unit, trace fossils include narrow vertical burrows in cross-bedded sandstones and borings in dinosaur bone, with the latter identified as the insect ichnotaxon Cubiculum ornatus. In the upper unit, several horizons preserve abundant footprints from theropod dinosaurs. Sauropod and ornithischian footprints are much rarer, similar to the record for fossil bone and teeth in the Kem Kem assemblage. The upper unit also preserves a variety of invertebrate traces including Conichnus (the resting trace of a sea-anemone), Scolicia (a gastropod trace), Beaconites (a probable annelid burrow), and subvertical burrows likely created by crabs for residence and detrital feeding on a tidal flat. The ichnofossil assemblage from the Upper Cretaceous Kem Kem beds contributes evidence for a transition from predominantly terrestrial to marine deposition. Body fossil and ichnofossil records together provide a detailed view of faunal diversity and local conditions within a fluvial and deltaic depositional setting on the northwestern coast of Africa toward the end of the Cretaceous.

  15. Dinosaur footprints and other ichnofauna from the cretaceous Kem Kem beds of Morocco.

    Directory of Open Access Journals (Sweden)

    Nizar Ibrahim

    Full Text Available We describe an extensive ichnofossil assemblage from the likely Cenomanian-age 'lower' and 'upper' units of the 'Kem Kem beds' in southeastern Morocco. In the lower unit, trace fossils include narrow vertical burrows in cross-bedded sandstones and borings in dinosaur bone, with the latter identified as the insect ichnotaxon Cubiculum ornatus. In the upper unit, several horizons preserve abundant footprints from theropod dinosaurs. Sauropod and ornithischian footprints are much rarer, similar to the record for fossil bone and teeth in the Kem Kem assemblage. The upper unit also preserves a variety of invertebrate traces including Conichnus (the resting trace of a sea-anemone, Scolicia (a gastropod trace, Beaconites (a probable annelid burrow, and subvertical burrows likely created by crabs for residence and detrital feeding on a tidal flat. The ichnofossil assemblage from the Upper Cretaceous Kem Kem beds contributes evidence for a transition from predominantly terrestrial to marine deposition. Body fossil and ichnofossil records together provide a detailed view of faunal diversity and local conditions within a fluvial and deltaic depositional setting on the northwestern coast of Africa toward the end of the Cretaceous.

  16. Debris-bed friction of hard-bedded glaciers

    Science.gov (United States)

    Cohen, D.; Iverson, N.R.; Hooyer, T.S.; Fischer, U.H.; Jackson, M.; Moore, P.L.

    2005-01-01

    [1] Field measurements of debris-bed friction on a smooth rock tablet at the bed of Engabreen, a hard-bedded, temperate glacier in northern Norway, indicated that basal ice containing 10% debris by volume exerted local shear traction of up to 500 kPa. The corresponding bulk friction coefficient between the dirty basal ice and the tablet was between 0.05 and 0.08. A model of friction in which nonrotating spherical rock particles are held in frictional contact with the bed by bed-normal ice flow can account for these measurements if the power law exponent for ice flowing past large clasts is 1. A small exponent (n glacier sliding at 20 m a-1 with a geothermally induced melt rate of 0.006 m a-1 and an effective pressure of 300 kPa can exceed 100 kPa. Debris-bed friction can therefore be a major component of sliding resistance, contradicting the common assumption that debris-bed friction is negligible. Copyright 2005 by the American Geophysical Union.

  17. Novel molecular fossils of bacteria: insights into hydrothermal origin of life.

    Science.gov (United States)

    Dai, Jianghong

    2012-10-07

    Hydrothermal vents, in particular, alkaline submarine vents, are potential systems for the origin of life. Early hydrothermal vents may have imprinted on biochemical processes and housekeeping proteins of life and have hallmarked key molecules. This essay introduces new information to this discussion by focusing on newly identified sulfur-modified DNA and a heretofore ignored anhydro bond of the cell wall peptidoglycan in bacteria. It is suggested that they are novel molecular fossils that are relevant to the settings of alkaline submarine vents and harbor clues of early life. As DNA and the cell wall are bound up with genetic information and the integrity of cell, respectively, these two molecular fossils may provide insights into hydrothermal origin of life from a new angle.

  18. Hooking some stem-group "worms": fossil lophotrochozoans in the Burgess Shale.

    Science.gov (United States)

    Butterfield, Nicholas J

    2006-12-01

    The fossil record plays a key role in reconstructing deep evolutionary relationships through its documentation of the early diverging stem groups leading to extant phyla. In the middle Cambrian Burgess Shale, two famously problematic worms, Odontogriphus and Wiwaxia, have recently been reinterpreted as stem-group molluscs based on their shared expression of a putative radula and putative ctenidia in Odontogriphus. More detailed analysis of these fossil structures, however, reveals pronounced anatomical and histological discrepancies with molluscan analogues, such that they are more reliably interpreted as primitive features of the superphylum Lophotrochozoa. In the absence of any obviously derived characters, Odontogriphus could be placed in the stem group of the Lophotrochozoa or on the stem of any of its constituent phyla, whereas the dorsal covering of chaetae in Wiwaxia identifies it as a stem-group polychaete. Despite their close relationship, these two jawed, segmented worms could conceivably represent the early stages of two separate phyla.

  19. Fossil energy. Program report, 1 October 1977-30 September 1978. [US DOE

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-12-01

    The Fossil Energy program is now in its second year under the Department of Energy. This document describes the Fossil Energy-supported contract and project activity for FY 1978. The primary thrust of the Program is on coal - especially direct coal combustion and what can be done to increase the environmental acceptability of coal. We are concerned with developing cleaner technologies, and we are working on precombustion cleanup, fluidized-bed combustion, and post-combustion cleanup. Longer range technologies are being developed to use coal more efficiently; for example, magnetohydrodynamics, fuel cells, and high-temperature turbine utilization. Another Fossil Energy priority is the development of a capability to produce synthetic fuels from coal. We are also engaged in a coal mining research and development program that focuses on increased mine productivity and workers' safety through the development of improved technologies. Our activity in the petroleum and gas research areas is intended to complement efforts in the private sector, which are to be further stimulated by new pricing or Federal incentives. Our present enhanced oil recovery efforts represent a shift in emphasis toward longer range, high-technology development projects instead of numerous field demonstrations and tests. The enhanced gas program emphasis activities to increase our knowledge of the size and economic productivity of the unconventional gas resources. We are also involved in oil shale development. We are continually assessing our program. Total annual funding has increased from $58 million in FY 1973 to $881 million in FY 1979.Fossil Energy is working closely with all parts of the Department of Energy, other appropriate Federal agencies, industry, and universities to insure that we maintain a balanced, aggressive, and responsive program suited to our national needs.

  20. Hawaii energy strategy project 2: Fossil energy review. Task 1: World and regional fossil energy dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Breazeale, K. [ed.; Isaak, D.T.; Yamaguchi, N.; Fridley, D.; Johnson, C.; Long, S.

    1993-12-01

    This report in the Hawaii Energy Strategy Project examines world and regional fossil energy dynamics. The topics of the report include fossil energy characteristics, the world oil industry including reserves, production, consumption, exporters, importers, refining, products and their uses, history and trends in the global oil market and the Asia-Pacific market; world gas industry including reserves, production, consumption, exporters, importers, processing, gas-based products, international gas market and the emerging Asia-Pacific gas market; the world coal industry including reserves, classification and quality, utilization, transportation, pricing, world coal market, Asia-Pacific coal outlook, trends in Europe and the Americas; and environmental trends affecting fossil fuels. 132 figs., 46 tabs.

  1. Distal tephras of the eastern Lake Victoria basin, equatorial East Africa: correlations, chronology and a context for early modern humans

    Science.gov (United States)

    Blegen, Nick; Tryon, Christian A.; Faith, J. Tyler; Peppe, Daniel J.; Beverly, Emily J.; Li, Bo; Jacobs, Zenobia

    2015-08-01

    The tephrostratigraphic framework for Pliocene and Early Pleistocene paleoanthropological sites in East Africa has been well established through nearly 50 years of research, but a similarly comprehensive framework is lacking for the Middle and particularly the Late Pleistocene. We provide the first detailed regional record of Late Pleistocene tephra deposits associated with artifacts or fossils from the Lake Victoria basin of western Kenya. Correlations of Late Pleistocene distal tephra deposits from the Wasiriya beds on Rusinga Island, the Waware beds on Mfangano Island and deposits near Karungu, mainland Kenya, are based on field stratigraphy coupled with 916 electron microprobe analyses of eleven major and minor element oxides from 50 samples. At least eight distinct distal tephra deposits are distinguished, four of which are found at multiple localities spanning >60 km over an approximately north to south transect. New optically stimulated luminescence dates help to constrain the Late Pleistocene depositional ages of these deposits. Our correlation and characterization of volcaniclastic deposits expand and refine the current stratigraphy of the eastern Lake Victoria basin. This provides the basis for relating fossil- and artifact-bearing sediments and a framework for ongoing geological, archaeological and paleontological studies of Late Pleistocene East Africa, a crucial time period for human evolution and dispersal within and out of Africa.

  2. The effect of early bed restorative exercise on gastrointestinal function of elderly pa-tients with biliary surgery%早期床上恢复性锻炼对老年胆道手术患者胃肠功能指标影响

    Institute of Scientific and Technical Information of China (English)

    陈秋菊; 唐梅; 易昌华; 张冰; 吴彩霞

    2015-01-01

    目的:探讨早期床上恢复性锻炼对老年胆道手术患者肠胃功能指标的影响,为临床提供相关依据。方法选择本院2008年12月至2012年2月接受腹部手术的老年患者126例做为研究对象,将所有患者严格按照随机原则分为早期锻炼组与非早期锻炼组,各63例。其中早期锻炼组进行早期床上恢复性锻炼,包括床上,床边,床下,肢体,日常生活运动,腹部按摩运动等;另外一组不进行。对比两组患者开始进食、胃肠道通气、肠鸣音恢复、排便时间、住院时间等胃肠功能指标。结果早期锻炼组的胃肠道症状显著少于非早期锻炼组,开始进食时间早于非早期锻炼组,胃肠通气时间、肠鸣音恢复、住院时间、排便时间等均少于非早期锻炼组,且两组差异均具有统计学意义( P<0.05)。结论早期床上恢复性锻炼可以加快老年胆道手术患者术后肠道功能的恢复,效果显著,具有较高的临床应用价值。%Objective To study the effect of early bed restorative exercise on gastrointestinal function of elderly patients with biliar-y surgery.Methods From December 2008 to February 2012, 126 cases accepted abdominal surgery were selected and divided randomly into early exercise and non-early exercise groups, each group had 63 cases.Early exercise group was given early bed restorative exercise.The time of eating, gastrointestinal ventilation, bowel sounds sound recovery, defecate time were compared.Results The gastrointestinal symp-toms of early exercise group was significantly less, the start time of eating was earlier; the gastrointestinal ventilation time, bowel sounds sound recovery, hospital stay, defecate time were less than those of non-early exercise group (P<0.05) .Conclusions Early bed restor-ative exercise could speed up the recovery of elderly patients with biliary surgery.

  3. A new fossil from the mid-Paleocene of New Zealand reveals an unexpected diversity of world's oldest penguins

    Science.gov (United States)

    Mayr, Gerald; De Pietri, Vanesa L.; Paul Scofield, R.

    2017-04-01

    We describe leg bones of a giant penguin from the mid-Paleocene Waipara Greensand of New Zealand. The specimens were found at the type locality of Waimanu manneringi and together with this species they constitute the oldest penguin fossils known to date. Tarsometatarsus dimensions indicate a species that reached the size of Anthropornis nordenskjoeldi, one of the largest known penguin species. Stem group penguins therefore attained a giant size very early in their evolution, with this gigantism existing for more than 30 million years. The new fossils are from a species that is phylogenetically more derived than Waimanu, and the unexpected coexistence of Waimanu with more derived stem group Sphenisciformes documents a previously unknown diversity amongst the world's oldest penguins. The characteristic tarsometatarsus shape of penguins evolved early on, and the significant morphological disparity between Waimanu and the new fossil conflicts with recent Paleocene divergence estimates for penguins, suggesting an older, Late Cretaceous, origin.

  4. New Miocene sulid birds from Peru and considerations on their Neogene fossil record in the Eastern Pacific Ocean

    Directory of Open Access Journals (Sweden)

    Marcelo Stucchi

    2016-06-01

    Full Text Available Boobies and gannets (family Sulidae are the most specialized plunge divers among seabirds. Their fossil record along the Pacific coast of South America extends to the early Middle Miocene. Here we describe three new species of sulids: Sula brandi sp. nov., Sula figueroae sp. nov., and Ramphastosula aguirrei sp. nov., from the early Late Miocene of the Pisco Formation (Peru. Two of them are relatives of the living genus Sula, which represents medium and large-sized boobies. A new species of the extinct genus Ramphastosula is also described, adding to the discussion of possible alternative feeding strategies among sulids. The fossil record suggests that sympatric sulids exhibit different body sizes at least since the Oligocene epoch, a strategy related with resource partitioning. Furthermore, we find current analysis and knowledge of the fossil record unsuitable to evaluate properly seabird diversity changes through time.

  5. Organic and mineral imprints in fossil photosynthetic mats of an East Antarctic lake.

    Science.gov (United States)

    Lepot, K; Compère, P; Gérard, E; Namsaraev, Z; Verleyen, E; Tavernier, I; Hodgson, D A; Vyverman, W; Gilbert, B; Wilmotte, A; Javaux, E J

    2014-09-01

    Lacustrine microbial mats in Antarctic ice-free oases are considered modern analogues of early microbial ecosystems as their primary production is generally dominated by cyanobacteria, the heterotrophic food chain typically truncated due to extreme environmental conditions, and they are geographically isolated. To better understand early fossilization and mineralization processes in this context, we studied the microstructure and chemistry of organo-mineral associations in a suite of sediments 50-4530 cal. years old from a lake in Skarvsnes, Lützow Holm Bay, East Antarctica. First, we report an exceptional preservation of fossil autotrophs and their biomolecules on millennial timescales. The pigment scytonemin is preserved inside cyanobacterial sheaths. As non-pigmented sheaths are also preserved, scytonemin likely played little role in the preservation of sheath polysaccharides, which have been cross-linked by ether bonds. Coccoids preserved thylakoids and autofluorescence of pigments such as carotenoids. This exceptional preservation of autotrophs in the fossil mats argues for limited biodegradation during and after deposition. Moreover, cell-shaped aggregates preserved sulfur-rich nanoglobules, supporting fossilization of instable intracellular byproducts of chemotrophic or phototrophic S-oxidizers. Second, we report a diversity of micro- to nanostructured CaCO3 precipitates intimately associated with extracellular polymeric substances, cyanobacteria, and/or other prokaryotes. Micro-peloids Type 1 display features that distinguish them from known carbonates crystallized in inorganic conditions: (i) Type 1A are often filled with globular nanocarbonates and/or surrounded by a fibrous fringe, (ii) Type 1B are empty and display ovoid to wrinkled fringes of nanocrystallites that can be radially oriented (fibrous or triangular) or multilayered, and (iii) all show small-size variations. Type 2 rounded carbonates 1-2 μm in diameter occurring inside autofluorescent

  6. Early Cretaceous angiosperms and beetle evolution

    OpenAIRE

    Bo eWang; Haichun eZhang; Edmund eJarzembowski

    2013-01-01

    The Coleoptera (beetles) constitute almost one–fourth of all known life-forms on earth. They are also among the most important pollinators of flowering plants, especially basal angiosperms. Beetle fossils are abundant, almost spanning the entire Early Cretaceous, and thus provide important clues to explore the co-evolutionary processes between beetles and angiosperms. We review the fossil record of some Early Cretaceous polyphagan beetles including Tenebrionoidea, Scarabaeoidea, Curculionoide...

  7. [Characterization of dinosaur fossils and their surrounding rocks by atomic emission spectrometry and X-ray powder diffractometry].

    Science.gov (United States)

    Yang, Qun; Wang, Yi-lin; Li, Chao-zhen; Yuan, Bo

    2005-02-01

    More dinosaur fossils have been found in the Laochangqing valley, Lufeng county than anywhere else in the world, and the dinosaur fossils found here cover the longest time span (including the early and middle Jurassic ages). This excavation offers an ideal experimental base for prehistoric biology studies. This paper presents an elementary analysis of the components and structure of the dinosaur fossils in three different geologic-layers and their surrounding rocks in the above mentioned area. Atomic emission spectrum shows that the fossils are rich in the contents of calcium (>5%) and phosphor, but low in the content of silicon (3%-8%), while the surrounding rocks are high in the content of silicon (>10%). Furthermore, XRD results show that the major compound of the fossils is CaCO3 (66%), followed by SiO2 (17%); while that of the surrounding rocks is SiO2 (>80%), followed by CaCO3 (dinosaur fossils from other rocks. This paper provides valuable data for further zoological studies on the living conditions and evolution of the dinosaurs in the Laochangqing valley, Lufeng county.

  8. Phylogeny, historical biogeography, and patterns of diversification for Pinus (Pinaceae): phylogenetic tests of fossil-based hypotheses.

    Science.gov (United States)

    Eckert, Andrew J; Hall, Benjamin D

    2006-07-01

    Pines comprise one of the largest coniferous genera, are distributed throughout the Northern Hemisphere, and have an abundant fossil record. Distributions of fossils have been used to derive a three-step hypothesis of early pine evolution, which postulates a Mesozoic origin for the genus, east-west expansions across Laurasia, and retraction into Eocene refugia. Here, we present phylogenetic tests of this hypothesis using chloroplast sequence data from four loci for 83 pine species. We used the fossil-based hypothesis to derive null expectations concerning monophyly of taxonomic groups, dates of cladogenesis, and patterns of diversification. Phylogenetic analyses using several algorithms subsequently provided rigorous tests of these expectations. Our inferred phylogenies illustrated broad congruence with taxonomic groups, but highlighted consistent problems within subgenus Strobus. Estimated minimum dates of divergence derived from relaxed clock methods were largely consistent with the fossil record and yielded a date for the ingroup node of Pinus of 128+/-4 mya, depending upon the calibration used for subgenus Pinus. Ancestral area reconstructions showed Pinus to have most likely originated in Eurasia. Major clades differed in biogeographic patterns, but were consistent with the fossil-based hypothesis. We found weak support, however, for a change in diversification rate in the Eocene as interpretations of fossil distributions would have predicted.

  9. Bugging forecast: unknown, disliked, occasionally intimate. Bed bugs in Germany meet unprepared people.

    Science.gov (United States)

    Seidel, Conrad; Reinhardt, Klaus

    2013-01-01

    Bed bugs appear to be feared more than vector insects and other household pests. The reasons for this exaggerated fear are not fully understood. One hypothesis is that the folk knowledge on recognising and controlling bed bugs decreased as bed bugs became rarer in the 1960s and led to irrational perceptions. Here, we examine people's ability to recognise a bed bug and their response what to do in case of an infestation. We found that 13% of a sample of 391 people in four large German cities recognised a bed bug; 15% of all respondents would call a pest controller in case of bed bug infestation. This results in the pessimistic estimate that 97% of all early-stage infestations could go untreated. We discuss additional scenarios. The effectiveness of efforts to educate people about the presence of bed bugs has never been tested, but our sample is useful to guide future studies. We found three sources of information were associated with increased recognition rates of bed bugs: a) previous contacts with bed bugs (60% recognition), b) knowledge from friends or relatives (25%) and school or education courses (15%). By contrast, people who heard of bed bugs from television, print media or the Internet showed reduced recognition rates. We propose that the former factors be tested for educational interventions. In Germany, the bed bug is an estranged creature to many people, a fact that seems to hinder rational approaches to their control.

  10. Bugging forecast: unknown, disliked, occasionally intimate. Bed bugs in Germany meet unprepared people.

    Directory of Open Access Journals (Sweden)

    Conrad Seidel

    Full Text Available Bed bugs appear to be feared more than vector insects and other household pests. The reasons for this exaggerated fear are not fully understood. One hypothesis is that the folk knowledge on recognising and controlling bed bugs decreased as bed bugs became rarer in the 1960s and led to irrational perceptions. Here, we examine people's ability to recognise a bed bug and their response what to do in case of an infestation. We found that 13% of a sample of 391 people in four large German cities recognised a bed bug; 15% of all respondents would call a pest controller in case of bed bug infestation. This results in the pessimistic estimate that 97% of all early-stage infestations could go untreated. We discuss additional scenarios. The effectiveness of efforts to educate people about the presence of bed bugs has never been tested, but our sample is useful to guide future studies. We found three sources of information were associated with increased recognition rates of bed bugs: a previous contacts with bed bugs (60% recognition, b knowledge from friends or relatives (25% and school or education courses (15%. By contrast, people who heard of bed bugs from television, print media or the Internet showed reduced recognition rates. We propose that the former factors be tested for educational interventions. In Germany, the bed bug is an estranged creature to many people, a fact that seems to hinder rational approaches to their control.

  11. Energy Ontologies: Wind, Biomass, and Fossil Transportation

    Directory of Open Access Journals (Sweden)

    Heidi Scott

    2016-06-01

    Full Text Available This article uses literary sources to draw ontological distinctions among three distinct energy sources: wind power, biomass, and fossil fuels. The primary aim is to demonstrate how radically our fossil fuel regime has changed human ontology in the last two centuries during which we have entered the Anthropocene. Because this radical transformation contains myriad elements, this article will focus on transportation: the speed, quality, and quantity of travel permitted by successive energy sources. To consider the comparative literatures of energy as they relate to transportation, we will begin with wind, then consider muscle-driven biomass giving way to coal locomotion, and conclude with the highest octane fuel, petroleum. The central interest is in how the fuel depicted in literature illuminates historical moments in which the interfaces between self, society, and nature are configured by specific energy regimes. By using literature as a source text, we may arrive at an emotionally and philosophically more robust synthesis of energy history than the social and natural sciences, relying upon objective accounts and statistics, are able to provide. By re-reading literature through the lens of the Anthropocene, we gain perspective on how earlier insights into the relationship between energy and experience can inform our explorations of today’s ontological reality. Energy literature instructs us out of the fossil fuel mindset of world domination and back to a physical realm in which we are small actors in a world guided by capricious forces. Such a reality requires hard muscular work and emotional immersion to restore an ethic of care and sustainability.

  12. The Early Flowers and Angiosperm Evolution

    DEFF Research Database (Denmark)

    Friis, Else Marie; Crane, P.R.; Pedersen, Kaj Raunsgaard

    The recent discovery of diverse fossil flowers and floral organs in Cretaceous strata has revealed astonishing details about the structural and systematic diversity of early angiosperms. Exploring the rich fossil record that has accumulated over the last three decades, this is a unique study...... based on research into Early and Late Cretaceous fossil floras from Europe and North America, the authors draw on direct palaeontological evidence of the pattern of angiosperm evolution through time. Synthesising palaeobotanical data with information from living plants, this unique book explores...... the latest research in the field, highlighting connections with phylogenetic systematics, structure and the biology of extant angiosperms....

  13. Hummingbird with modern feathering: an exceptionally well-preserved Oligocene fossil from southern France

    Science.gov (United States)

    Louchart, Antoine; Tourment, Nicolas; Carrier, Julie; Roux, Thierry; Mourer-Chauviré, Cécile

    2008-02-01

    Hummingbirds (Trochilidae) today have an exclusively New World distribution, but their pre-Pleistocene fossil record comes from Europe only. In this study, we describe an exceptionally preserved fossil hummingbird from the early Oligocene of southeastern France. The specimen is articulated, with a completely preserved beak and feathering. Osteological characters allow to identify it as Eurotrochilus sp. This genus is a stem group representative of Trochilidae and was recently described from the early Oligocene of southern Germany. The new fossil reveals that these European Trochilidae were remarkably modern in size, skeletal proportions and the shape of the wing, tail and beak and hyoid bones. These features confirm the early acquisition of the abilities of hovering and nectarivory in hummingbirds, probably before the Oligocene. In several morphological characteristics, they resemble members of the ‘true hummingbirds’ (subfamily Trochilinae) and differ from hermits (Phaethornithinae). These features, which include a short and square tail and a moderately long, almost straight beak, appear to be primitive within the family Trochilidae.

  14. Cambrian Burgess Shale-type deposits share a common mode of fossilization

    Science.gov (United States)

    Gaines, Robert R.; Briggs, Derek E. G.; Yuanlong, Zhao

    2008-10-01

    Although Cambrian Burgess Shale-type (BST) biotas arefundamental to understanding the radiation of metazoans, thenature of their extraordinary preservation remains controversial.There remains disagreement about the importance of the roleof early mineral replication of soft tissues versus the conservationof primary organic remains. Most prior work focused on soft-bodiedfossils from the two most important BST biotas, those of theBurgess Shale (Canada) and Maotianshan Shale (Chengjiang, China).Fossils from these two deposits do not provide ideal candidatesfor specimen-level taphonomic study because they have been altered:the Burgess Shale by greenschist facies metamorphism and theMaotianshan Shale by intensive subsurface weathering. Elementalmapping of soft-bodied fossils from 11 other BST deposits worldwidedemonstrates that BST preservation represents a single majortaphonomic pathway that may share a common cause wherever itoccurs. The conservation of organic tissues, and not early authigenicmineralization, is the primary mechanism responsible for thepreservation of BST assemblages. Early authigenic mineral replacementpreserves certain anatomical features of some specimens, butthe preservation of non-biomineralized BST fossils requiressuppression of the processes that normally lead to the degradationof organic remains in marine environments.

  15. Comparing amber fossil assemblages across the Cenozoic.

    Science.gov (United States)

    Penney, David; Langan, A Mark

    2006-06-22

    To justify faunistic comparisons of ambers that differ botanically, geographically and by age, we need to determine that resins sampled uniformly. Our pluralistic approach, analysing size distributions of 671 fossilized spider species from different behavioural guilds, demonstrates that ecological information about the communities of two well-studied ambers is retained. Several lines of evidence show that greater structural complexity of Baltic compared to Dominican amber trees explains the presence of larger web-spinners. No size differences occur in active hunters. Consequently, we demonstrate for the first time that resins were trapping organisms uniformly and that comparisons of amber palaeoecosystem structure across deep time are possible.

  16. Future requirements for fossil power plants

    Directory of Open Access Journals (Sweden)

    Spliethoff H.

    2013-06-01

    Full Text Available The fast increasing installation of technologies to convert renewable energy into power influences the operation of conventional power plants. New requirements on the technology, on the operation and on the economic have to be considered for already running and future power plants. Currently, first experiences with such a production and market situation are available. Technologies are discussed to store power and to reduce CO2 emissions. New compensation models are necessary to enable economic operation of fossil power plants in base load. This article gives a short review about available technologies and future challenges.

  17. Fossil Diatoms in a New Carbonaceous Meteorite

    Science.gov (United States)

    Wickramasinghe, N. C.; Wallis, J.; Wallis, D. H.; Samaranayake, Anil

    2013-01-01

    We report the discovery for the first time of diatom frustules in a carbonaceous meteorite that fell in the North Central Province of Sri Lanka on 29 December 2012. Contamination is excluded by the circumstance that the elemental abundances within the structures match closely with those of the surrounding matrix. There is also evidence of structures morphologically similar to red rain cells that may have contributed to the episode of red rain that followed within days of the meteorite fall. The new data on "fossil" diatoms provide strong evidence to support the theory of cometary panspermia.

  18. Recent developments in biodesulfurization of fossil fuels.

    Science.gov (United States)

    Xu, Ping; Feng, Jinhui; Yu, Bo; Li, Fuli; Ma, Cuiqing

    2009-01-01

    The emission of sulfur oxides can have adverse effects on the environment. Biodesulfurization of fossil fuels is attracting more and more attention because such a bioprocess is environmentally friendly. Some techniques of desulfurization have been used or studied to meet the stricter limitation on sulfur content in China. Recent advances have demonstrated the mechanism and developments for biodesulfurization of gasoline, diesel and crude oils by free cells or immobilized cells. Genetic technology was also used to improve sulfur removal efficiencies. In this review, we summarize recent progress mainly in China on petroleum biodesulfurization.

  19. A lethal combination of toxins and biofilms aids soft tissue fossilization

    Science.gov (United States)

    MacKenzie, L. A.; Hinman, N. W.; Kohn, M. J.; Olin, P. H.

    2012-12-01

    Biofilms, thin microbial communities encased in extracellular polymeric substances, are thought to aid in fossilization, particularly in cases of extraordinary preservation of soft tissues in Konservat-Lagerstätten deposits. The mechanisms by which this occurs, however, are poorly understood. Modern marine biofilms take up trace elements (e.g., Cu, P, Fe, Zn, Cd), some of which are toxic. In this study we investigated trace element patterns across worm fossils from the Early Cambrian Chengjiang biota (Yunnan, China) to explore whether toxic metals preferentially accumulated in soft tissues, retarding biodegradation and promoting extraordinary preservation. This biota is the oldest of the Burgess Shale Type (BST) Lagerstätten, which preserve soft-bodied fossils that range in age from early Cambrian to Ordovician. Concentrations of 24 light elements, transition metals, heavy metals, actinides and lanthanides were measured using laser-ablation ICP-MS in 2-4 mm long transects across rock matrix and 1-2 mm wide fossils to create matrix-worm-matrix geochemical profiles. Spatial and compositional resolutions were ~50 μm and ~1ppm. Six worm fossils were analyzed, and all show higher concentrations of P, Sc, V, Cr, Fe, Ni, Cu, Mo, Sb, Th, and U than the matrix. Increases in Na, Mg, Al, K, Ca, Mn, Co, Sr, Ba, Ce, and Pb were found in some, but not all samples. None of the samples showed significant increases in Ti. Abiotic processes cannot explain increased concentrations of all of these elements, which include both redox-sensitive and immobile elements. Instead we propose that biofilms formed on the surface of the organisms shortly after death (hours to days). Bioaccumulation of toxic trace elements sealed the worms under a thin, deadly trace-element-rich film that prevented further degradation. This process allowed diagenetic cements to form a rigid rock matrix and preserve these delicate fossils. If so, trace element accumulation by biofilms may provide the key for

  20. Torsion testing of bed joints

    DEFF Research Database (Denmark)

    Hansen, Klavs Feilberg; Pedersen, Carsten Mørk

    2008-01-01

    be carried out directly in a normal testing machine. The torsion strength is believed to be the most important parameter in out-of-plane resistance of masonry walls subjected to bending about an axis perpendicular to the bed joints. The paper also contains a few test results from bending of small walls about...... an axis perpendicular to the bed joints, which indicate the close connection between these results and results from torsion tests. These characteristics make the torsion strength well suited to act as substitute parameter for the bending strength of masonry about an axis perpendicular to the bed joints....

  1. Technological research and development of fossil fuels; Ricerca e sviluppo tecnologico per lo sfruttamento ottimale dei combustibili fossili

    Energy Technology Data Exchange (ETDEWEB)

    Minghetti, E.; Palazzi, G. [ENEA, Centro Ricerche Casaccia, Rome (Italy). Dip. Energia

    1995-05-01

    The aim of the present document is to supply general information concerning fossil fuels that represent, today and for the near future, the main energy source of our planet. New fossil fuel technologies are in continual development with two principal goals: to decrease environmental impact and increase transformation process efficiency. Examples of this effort are: (1) gas-steam combined cycles integrated with coal gasification plants, or with pressurized-fluidized-bed combustors; (2) new cycles with humid air or coal direct fired turbine, now under development. In the first part of this document the international and national energy situations and trends are shown. After some brief notes on environment problems and alternative fuels, such as biomasses and municipal wastes, technological aspects, mainly relevant to increasing fossil-fueled power plant performances, are examined in greater depth. Finally the research and technological development activities of ENEA (National Agency for New technologies, Energy and the Environment) Engineering Branch in order to improve fossil fuels energy and environmental use are presented.

  2. The First Galaxies and the Likely Discovery of Their Fossils in the Local Group

    Directory of Open Access Journals (Sweden)

    Massimo Ricotti

    2010-01-01

    Full Text Available The lower bound for the mass of a galaxy is unknown, as are the typical luminosity of the smallest galaxies and their numbers. The answers depend on the extent to which star formation in the first population of small mass halos may be suppressed by radiative feedback loops. If early populations of dwarf galaxies did form in significant number before reionization, their “fossils” should be found today in the Local Group. This paper reviews our ongoing efforts to simulate and identify fossil dwarfs in the Local Group. It is widely believed that reionization stopped star formation in fossil dwarfs. However, here we dispute this idea and discuss a physical mechanism whereby recent episodes of star formation would be produced in some fossil dwarfs that, hence, may characterized by a bimodal star formation history. The same mechanism could turn dark halos that failed to form stars before reionization into gas-rich “dark galaxies”. We believe that current observational data supports the thesis that a fraction of the new ultra-faint dwarfs discovered in the Local Group are fossil dwarfs and we predict the existence of a population of ultra-faint dwarfs with lower surface brightness than currently observed.

  3. Xenopus in Space and Time: Fossils, Node Calibrations, Tip-Dating, and Paleobiogeography.

    Science.gov (United States)

    Cannatella, David

    2015-01-01

    Published data from DNA sequences, morphology of 11 extant and 15 extinct frog taxa, and stratigraphic ranges of fossils were integrated to open a window into the deep-time evolution of Xenopus. The ages and morphological characters of fossils were used as independent datasets to calibrate a chronogram. We found that DNA sequences, either alone or in combination with morphological data and fossils, tended to support a close relationship between Xenopus and Hymenochirus, although in some analyses this topology was not significantly better than the Pipa + Hymenochirus topology. Analyses that excluded DNA data found strong support for the Pipa + Hymenochirus tree. The criterion for selecting the maximum age of the calibration prior influenced the age estimates, and our age estimates of early divergences in the tree of frogs are substantially younger than those of published studies. Node-dating and tip-dating calibrations, either alone or in combination, yielded older dates for nodes than did a root calibration alone. Our estimates of divergence times indicate that overwater dispersal, rather than vicariance due to the splitting of Africa and South America, may explain the presence of Xenopus in Africa and its closest fossil relatives in South America.

  4. Earliest and first Northern Hemispheric hoatzin fossils substantiate Old World origin of a "Neotropic endemic".

    Science.gov (United States)

    Mayr, Gerald; De Pietri, Vanesa L

    2014-02-01

    The recent identification of hoatzins (Opisthocomiformes) in the Miocene of Africa showed part of the evolution of these birds, which are now only found in South America, to have taken place outside the Neotropic region. Here, we describe a new fossil species from the late Eocene of France, which constitutes the earliest fossil record of hoatzins and the first one from the Northern Hemisphere. Protoazin parisiensis gen. et sp. nov. is more closely related to South American Opisthocomiformes than the African taxon Namibiavis and substantiates an Old World origin of hoatzins, as well as a relictual distribution of the single extant species. Although recognition of hoatzins in Europe may challenge their presumed transatlantic dispersal, there are still no North American fossils in support of an alternative, Northern Hemispheric, dispersal route. In addition to Opisthocomiformes, other avian taxa are known from the Cenozoic of Europe, the extant representatives of which are only found in South America. Recognition of hoatzins in the early Cenozoic of Europe is of particular significance because Opisthocomiformes have a fossil record in sub-Saharan Africa, which supports the hypothesis that extinction of at least some of these "South American" groups outside the Neotropic region was not primarily due to climatic factors.

  5. CO2 emissions mitigation and fossil fuel markets: Dynamic and international aspects of climate policies

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, Nico; Bosetti, Valentina; Hamdi-Cherif, Meriem; Kitous, Alban; McCollum, David; Mejean, Aurelie; Rao, Shilpa; Turton, Hal; Paroussos, Leonidas; Ashina, Shuichi; Calvin, Katherine V.; Wada, Kenichi; Van Vuuren, Detlef

    2015-01-01

    This paper explores a multi-model scenario ensemble to assess the impacts of idealized and non-idealized climate change stabilization policies on fossil fuel markets. Under idealized conditions climate policies significantly reduce coal use in the short- and long-term. Reductions in oil and gas use are much smaller, particularly until 2030, but revenues decrease much more because oil and gas prices are higher and decrease with mitigation. A first deviation from the optimal transition pathway relaxes global emission targets until 2030, in accordance with the Copenhagen pledges and regionally-specific low-carbon technology targets. Fossil fuel markets revert back to the no-policy case: though coal use increases strongest, revenue gains are higher for oil and gas. To balance the carbon budget over the 21st century, the long-term reallocation of fossil fuels is significantly larger - twice and more - than the short-term distortion. This amplifying effect results from coal lock-in and inter-fuel substitution effects. The second deviation from the optimal transition pathway relaxes the global participation assumption. The result here is less clear cut across models, as we find carbon leakage effects ranging from positive to negative because leakage and substitution patterns of coal, oil, and gas differ. In summary, distortions of fossil fuel markets resulting from relaxed short-term global emission targets are more important and less uncertain than the issue of carbon leakage from early mover action.

  6. Rare earth element composition of Paleogene vertebrate fossils from Toadstool Geologic Park, Nebraska, USA

    Energy Technology Data Exchange (ETDEWEB)

    Grandstaff, D.E., E-mail: grand@temple.edu [Department of Earth and Environmental Science, Temple University, Philadelphia, PA 19122 (United States); Terry, D.O. [Department of Earth and Environmental Science, Temple University, Philadelphia, PA 19122 (United States)

    2009-04-15

    Fossil bones and teeth from terrestrial environments encode unique rare earth and trace element (REE and TE) signatures as a function of redox conditions, pH, concentrations of complexing ligands, and water-colloid interactions. This signature is set early in the fossilization process and serves as a paleoenvironmental and paleoclimatic proxy. These signatures can also be used to interpret temporal and spatial averaging within vertebrate accumulations, and can help relocate displaced fossil bones back into stratigraphic context. Rare earth elements in vertebrate fossils from upper Eocene and Oligocene strata of Toadstool Geologic Park, northwestern Nebraska, record mixing and evolution of Paleogene vadose or groundwaters and variations in paleoenvironments. REE signatures indicate that HREE-enriched alkaline groundwater reacted with LREE- and MREE-enriched sediments to produce 3-component mixtures. REE signatures become increasingly LREE- and MREE-enriched toward the top of the studied section as the paleoenvironment became cooler and drier, suggesting that REE signatures may be climate proxies. Time series analysis suggests that REE ratios are influenced by cycles of ca. 1050, 800, 570, 440, and 225 ka, similar to some previously determined Milankovitch astronomical and climate periodicities.

  7. Charles Darwin's beagle voyage, fossil vertebrate succession, and "the gradual birth & death of species".

    Science.gov (United States)

    Brinkman, Paul D

    2010-01-01

    The prevailing view among historians of science holds that Charles Darwin became a convinced transmutationist only in the early spring of 1837, after his Beagle collections had been examined by expert British naturalists. With respect to the fossil vertebrate evidence, some historians believe that Darwin was incapable of seeing or understanding the transmutationist implications of his specimens without the help of Richard Owen. There is ample evidence, however, that he clearly recognized the similarities between several of the fossil vertebrates he collected and some of the extant fauna of South America before he returned to Britain. These comparisons, recorded in his correspondence, his diary and his notebooks during the voyage, were instances of a phenomenon that he later called the "law of the succession of types." Moreover, on the Beagle, he was following a geological research agenda outlined in the second volume of Charles Lyell's Principles of Geology, which implies that paleontological data alone could provide an insight into the laws which govern the appearance of new species. Since Darwin claims in On the Origin of Species that fossil vertebrate succession was one of the key lines of evidence that led him to question the fixity of species, it seems certain that he was seriously contemplating transmutation during the Beagle voyage. If so, historians of science need to reconsider both the role of Britain's expert naturalists and the importance of the fossil vertebrate evidence in the development of Darwin's ideas on transmutation.

  8. Do 'Early Birds' Get the Healthier Worm?

    Science.gov (United States)

    ... medlineplus.gov/news/fullstory_163902.html Do 'Early Birds' Get the Healthier Worm? Late-to-bed types ... 2017 FRIDAY, March 3, 2017 (HealthDay News) -- Early birds may have a leg up over night owls ...

  9. Further support for a Cretaceous age for the feathered-dinosaur beds of Liaoning,China:New 40Ar/39Ar dating of the Yixian and Tuchengzi Formations

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    We report new 40Ar/39Ar dating results obtained from total fusion and incremental-heating analyses of sanidine and biotite from three tuffs found interbedded within the fossil-bearing deposits of Liaoning, northeast China. The first is a new sample of the Bed 6 Sihetun tuff from the Yixian Formation, previously dated by our team as middle Early Cretaceous, and recently considered by Lo et al., partially reset due to metamorphism from a nearby basaltic sill. The second is the Yixian Bed 9 tuff from Hengdaozi considered by Lo et al. to be unaffected by metamorphism and whose age, based on total fusion 40Ar/39Ar dating of biotite, argues for a Jurassic age for the Yixian Formation.The third tuff is a previously undated tuff from the upper part of the underlying Tuchengzi Formation. Single crystal total fusion 40Ar/39Ar analyses of the Sihetun sanidine showed homogeneous radiogenic Ar, Ca/K ratios, excellent reproducibility and gave a mean age of 125.0 ± 0.18 (1SD) ±0.04 (SE) Ma. Single sanidine crystal total fusion 40Ar/39Aranalyses of the Hengdaozi tuff gave a mean age of 125.0 +0.19 (1SD) ± 0.04 (SE) Ma, which is indistinguishable from the Sihetun tuff. The Tuchengzi Formation tuff gave a mean age of 139.4 ± 0.19 (1SD) ± 0.05 (SE) Ma. Detailed laser incremental-heating analyses of biotite from Sihetun, Hengdaozi, and Tuchengzi tuffs show disturbed Ar release patterns and evidence of trapped argon components. We conclude from these analyses that the total fusion dates on biotite by Lo et al. are erroneously old and isotopic dating of both biotite and sanidine from tuffs of the Yixian Formation point to a middle Early Cretaceous age. The upper part of the Tuchengzi Formation can be referred to the Early Cretaceous.``

  10. Stable isotope-based Plio-Pleistocene southern hemisphere climate and vegetation reconstructions (Chiwondo Beds, Northern Malawi)

    Science.gov (United States)

    Luedecke, T.; Thiemeyer, H.; Schrenk, F.; Mulch, A.

    2013-12-01

    Oxygen and carbon isotope geochemistry of multi-proxy archives is a powerful tool to reconstruct paleoclimatic and paleoenvironmental conditions in particular when climate seasonality plays a key role in the evolution of ecosystems. Here we present the first pedogenic Plio-Pleistocene long-term East-African carbon, oxygen and clumped isotope (Δ47) records from some of the earliest hominid fossil sites in Eastern Africa. The studied 5.0 to 0.6 Ma paleosol, fluviatile, and lacustrine deposits of the Chiwondo Beds (Karonga-Chilumba area, NE shore of Lake Malawi) comprise abundant pedogenic carbonates and fossil remains of a diverse fauna which are dominated by large terrestrial mammals. The sediments are also home to two hominid fossil finds, a maxillary fragment of Paranthropus boisei and a mandible of Homo rudolfensis, both dated around 2.4 Ma. Here, we present stable carbon (δ13C) and oxygen (δ18O) isotope data from fossil enamel of different suid, bovid, and equid species as well as δ13C and δ18O values of pedogenic carbonate. We complement the latter by clumped isotope data as proxy for soil temperature. Our data represent the first southern hemisphere record in the East African Rift (EAR), a region particularly interesting for reconstructing vegetation patterns and correlating these across the ITCZ with data on the evolution and migration of early hominids. As our study site is situated between the well-known hominid-bearing sites of eastern and southern Africa it fills an important geographical gap for early hominid research. The δ13C values of enamel and pedogenic carbonate assess the evolutionary history of C3 and C4 biomass which is closely linked to climate patterns in the Malawi Rift Valley during the time of early hominid evolution. The reconstruction of the development of C4-grasslands give insights of changing atmospheric CO2-concentration, seasonality and distribution of precipitation, and the retreat of tree cover. Results of almost 500

  11. FOSSIL2 energy policy model documentation: generic structures of the FOSSIL2 model

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-10-01

    This report discusses the structure, derivations, assumptions, and mathematical formulation of the FOSSIL2 model. Each major facet of the model - supply/demand interactions, industry financing, and production - has been designed to parallel closely the actual cause/effect relationships determining the behavior of the United States energy system. The data base for the FOSSIL2 program is large. When possible, all data were obtained from sources well known to experts in the energy field. Cost and resource estimates are based on DOE data whenever possible. This report presents the FOSSIL2 model at several levels. In Volume I, an overview of the basic structures, assumptions, and behavior of the FOSSIL2 model is presented so that the reader can understand the results of various policy tests. The discussion covers the three major building blocks, or generic structures, used to construct the model: supply/demand balance; finance and capital formation; and energy production. These structures reflect the components and interactions of the major processes within each energy industry that directly affect the dynamics of fuel supply, demand, and price within the energy system as a whole.

  12. Experimental mineralization of crustacean eggs leads to surprising tissue conservation: new implications for the fossilization of Precambrian-Cambrian embryos

    OpenAIRE

    2011-01-01

    Phosphatized globular microfossils from the Ediacaran and Lower Cambrian of South China represent an impressive record of early animal evolution and development, however their affinity based on putative embryonic metazoan, bacterial and inorganic features is strongly debated. Understanding key processes and conditions that cause exceptional egg and embryo preservation and fossilization are therefore crucial for a reliable interpretation of their phylogenetic position. Taphonomic experime...

  13. Upper Palaeolithic and Mesolithic human fossils from Moravia and Bohemia (Czech Republic) : Some new C-14 dates

    NARCIS (Netherlands)

    Svoboda, JA; Van der Plicht, J; Kuzelka, [No Value; Svoboda, Jiři A.; Kuželka, Vítězslav

    2002-01-01

    New radiocarbon dates from four Moravian and bohemian sites are presented and linked to previous work on the depositional contexts of human fossils at similar sites in the region. Whilst dates from Mladec confirm its early Upper Palaeolithic age, the chronologies of the other three sites require rev

  14. Atmospheric Lifetime of Fossil Fuel Carbon Dioxide

    Science.gov (United States)

    Archer, David; Eby, Michael; Brovkin, Victor; Ridgwell, Andy; Cao, Long; Mikolajewicz, Uwe; Caldeira, Ken; Matsumoto, Katsumi; Munhoven, Guy; Montenegro, Alvaro; Tokos, Kathy

    2009-05-01

    CO2 released from combustion of fossil fuels equilibrates among the various carbon reservoirs of the atmosphere, the ocean, and the terrestrial biosphere on timescales of a few centuries. However, a sizeable fraction of the CO2 remains in the atmosphere, awaiting a return to the solid earth by much slower weathering processes and deposition of CaCO3. Common measures of the atmospheric lifetime of CO2, including the e-folding time scale, disregard the long tail. Its neglect in the calculation of global warming potentials leads many to underestimate the longevity of anthropogenic global warming. Here, we review the past literature on the atmospheric lifetime of fossil fuel CO2 and its impact on climate, and we present initial results from a model intercomparison project on this topic. The models agree that 20-35% of the CO2 remains in the atmosphere after equilibration with the ocean (2-20 centuries). Neutralization by CaCO3 draws the airborne fraction down further on timescales of 3 to 7 kyr.

  15. Species longevity in North American fossil mammals.

    Science.gov (United States)

    Prothero, Donald R

    2014-08-01

    Species longevity in the fossil record is related to many paleoecological variables and is important to macroevolutionary studies, yet there are very few reliable data on average species durations in Cenozoic fossil mammals. Many of the online databases (such as the Paleobiology Database) use only genera of North American Cenozoic mammals and there are severe problems because key groups (e.g. camels, oreodonts, pronghorns and proboscideans) have no reliable updated taxonomy, with many invalid genera and species and/or many undescribed genera and species. Most of the published datasets yield species duration estimates of approximately 2.3-4.3 Myr for larger mammals, with small mammals tending to have shorter species durations. My own compilation of all the valid species durations in families with updated taxonomy (39 families, containing 431 genera and 998 species, averaging 2.3 species per genus) yields a mean duration of 3.21 Myr for larger mammals. This breaks down to 4.10-4.39 Myr for artiodactyls, 3.14-3.31 Myr for perissodactyls and 2.63-2.95 Myr for carnivorous mammals (carnivorans plus creodonts). These averages are based on a much larger, more robust dataset than most previous estimates, so they should be more reliable for any studies that need species longevity to be accurately estimated. © 2013 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

  16. Cladistics and the hominid fossil record.

    Science.gov (United States)

    Trinkaus, E

    1990-09-01

    Cladistic methodology has become common in phylogenetic analyses of the hominid fossil record. Even though it has correctly placed emphasis on morphology for the primary determination of affinities between groups and on explicit statements regarding traits and methods employed in making phylogenetic assessments, cladistics nonetheless has limitations when applied to the hominid fossil record. These include 1) the uncritical assumption of parsimony, 2) uncertainties in the identification of homoplasies, 3) difficulties in the appropriate delimitation of samples for analysis, 4) failure to account for normal patterns of variation, 5) methodological problems with the appropriate identification of morphological traits involving issues of biological relevance, intercorrelation, primary versus secondary characters, and the use of continuous variables, 6) issues of polarity identification, and 7) problems in hypothesis testing. While cladistics has focused attention on alternative phylogenetic reconstructions in hominid paleontology and on explicit statements regarding their morphological and methodological underpinnings, its biological limitations are too abundant for it to be more than a heuristic device for the preliminary ordering of complex human paleontological and neonatological data.

  17. A Study of Interlanguage Fossilization in College Students' English writing

    Institute of Scientific and Technical Information of China (English)

    王茹

    2014-01-01

    English writing is the college students’synthetical application about the knowledge of English. English writing, how-ever, is the weak segment of the college students' English learning all the time. Based on the researches home and abroad, the pa-per makes an implicational study on interlanguage fossilization in English writing of Chinese college students. Though probing the causes of fossilization in English writing, the paper proposes some measures to reduce the fossilization. In the chapter one, the paper introduces simply the interlanguage fossilization. In the chapter two, the paper analyzes college students English writing and get the causal factors of fossilization:unfavorite learning motivation of students, ineffective feedback to errors, interference of the mother tongue. Then , at the last chapter, the paper put up some measures to overcome and avoid the fossilization in college stu-dents' English writing:promoting students' motivation, providing right feedback, avoiding mother tongue interference.

  18. Late Miocene fossils from shallow marine sediments in Brunei Darussalam: systematics, palaeoenvironment and ecology.

    Science.gov (United States)

    Roslim, Amajida; Briguglio, Antonino; Kocsis, László; Ćorić, Stjepan; Razak, Hazirah

    2016-04-01

    The geology of Brunei Darussalam is fascinating but difficult to approach: rainforests and heavy precipitation tend to erode and smoothen the landscape limiting rocks exposure, whereas abundant constructions sites and active quarries allow the creation of short time available outcrop, which have to be immediately sampled. The stratigraphy of Brunei Darussalam comprises mainly Neogene sediments deposited in a wave to tide dominated shallow marine environment in a pure siliciclastic system. Thick and heavily bioturbated sandstone layers alternate to claystone beds which occasionally yield an extraordinary abundance and diversity of fossils. The sandstones, when not bioturbated, are commonly characterized by a large variety of sedimentary structures (e.g., ripple marks, planar laminations and cross beddings). In this study, we investigate the sediments and the fossil assemblages to record the palaeoenvironmental evolution of the shallow marine environment during the late Miocene, in terms of sea level change, chemostratigraphy and sedimentation rate. The study area is one of the best in terms of accessibility, extension, abundance and preservation of fossils; it is located in the region -'Bukit Ambug' (Ambug Hill), Tutong District. The fossils fauna collected encompasses mollusks, decapods, otoliths, shark and ray teeth, amber, foraminifera and coccolithophorids. In this investigation, sediment samples were taken along a section which measures 62.5 meters. A thick clay layer of 9 meters was sampled each 30 cm to investigate microfossils occurrences. Each sample was treated in peroxide and then sieved trough 63 μm, 150μm, 250μm, 450μm, 600μm, 1mm and 2mm sieves. Results point on the changes in biodiversity of foraminifera along the different horizons collected reflecting sea level changes and sediment production. The most abundant taxa identified are Pseoudorotalia schroeteriana, Ampistegina lessonii, Elphidium advenum, Quinqueloculina sp., Bolivina sp

  19. "Dead in bed": a tragic complication of type 1 diabetes mellitus.

    LENUS (Irish Health Repository)

    O'Reilly, M

    2010-12-01

    "Dead in bed" is a tragic description of a particular type of sudden death in type 1 diabetes mellitus (DM). Patients are typically found dead in the early morning, lying in an undisturbed bed, having been well the previous evening. The incidence of "dead in bed" syndrome is not known but studies suggest figures of between 4.7 and 27.3% of all unexplained deaths in type 1 DM. The pathogenesis is unclear but patients typically have a preceding history of recurrent severe hypoglycaemia. We describe two cases of "dead in bed" syndrome which occurred at our institution within a 12-month period.

  20. Bed Bugs: The Australian Response

    Science.gov (United States)

    Doggett, Stephen L.; Orton, Christopher J.; Lilly, David G.; Russell, Richard C.

    2011-01-01

    Australia has experienced a sudden and unexpected resurgence in bed bug infestations from both Cimex lectularius L. and Cimex hemipterus F. A survey in 2006 revealed that infestations had increased across the nation by an average of 4,500% since the start of the decade. In response, a multi-disciplinary approach to combat the rise of this public health pest was implemented and involved the coordinated efforts of several organizations. The key components of the strategy included the introduction of a pest management standard ‘A Code of Practice for the Control of Bed Bug Infestations in Australia’ that defines and promotes ‘best practice’ in bed bug eradication, the development of a policy and procedural guide for accommodation providers, education of stakeholders in best management practices, and research. These strategies continue to evolve with developments that lead to improvements in ‘best practice’ while bed bugs remain problematic in Australia. PMID:26467616