Preservation and phylogeny of Cambrian ecdysozoans tested by experimental decay of Priapulus

Science.gov (United States)

Sansom, Robert S.

2016-09-01

The exceptionally preserved Cambrian fossil record provides unique insight into the early evolutionary history of animals. Understanding of the mechanisms of exceptional soft tissue preservation frames all interpretations of the fauna and its evolutionary significance. This is especially true for recent interpretations of preserved nervous tissues in fossil ecdysozoans. However, models of soft tissue preservation lack empirical support from actualistic studies. Here experimental decay of the priapulid Priapulus reveal consistent bias towards rapid loss of internal non-cuticular anatomy compared with recalcitrant cuticular anatomy. This is consistent with models of Burgess Shale-type preservation and indicates that internal tissues are unlikely to be preserved with fidelity if organically preserved. This pattern, along with extreme body margin distortion, is consistent with onychophoran decay, and is therefore resolved as general for early ecdysozoans. Application of these patterns to phylogenetic data finds scalidophoran taxa to be very sensitive to taphonomically informed character coding, but not panarthropodan taxa. Priapulid decay also have unexpected relevance for interpretation of myomeres in fossil chordates. The decay data presented serve not only as a test of models of preservation but also a framework with which to interpret ecdysozoan fossil anatomies, and the subsequent evolutionary inferences drawn from them.

Mechanism for Burgess Shale-type preservation

DEFF Research Database (Denmark)

Gaines, Robert R.; Hammarlund, Emma U.; Hou, Xianguang

2012-01-01

Exceptionally preserved fossil biotas of the Burgess Shale and a handful of other similar Cambrian deposits provide rare but critical insights into the early diversification of animals. The extraordinary preservation of labile tissues in these geographically widespread but temporally restricted......-oxygen bottom water conditions at the sites of deposition resulted in reduced oxidant availability. Subsequently, rapid entombment of fossils in fine-grained sediments and early sealing of sediments by pervasive carbonate cements at bed tops restricted oxidant flux into the sediments. A permeability barrier...

Unraveling Molecular Mechanisms for the Unusual Fossil Preservation and Biomineralization Pathways in Tlayúa, the Mexican Solenhofen

Science.gov (United States)

Cervini-Silva, J.; Fakra, S.; Alvarado-Ortega, J.; Cornejo-Garrido, H.; Marcus, M.; Hao, Z.; Espinosa-Arruberena, L.; Banfield, J.

2007-12-01

The Tlayúa slurry constitutes the most important paleontological locality in the American continent, and constitutes the second most important locality in its genre worldwide. The importance of Tlayúa strives in the fact that a great diversity of marine and terrestrial fossils in perfect state of preservation have been found, with ages surpassing 115 million yrs. Paleomagnetic determinations and biostratigraphic determinations conducted in amonites and belemnites indicate that the formation of the Tlayúa slurry dates back to the late Albian. On the other hand, fish, reptiles, invertebrates, and vegetables fossil specimens have been found to date back to the Mesozoic Era. Because of this fact is unprecedented worldwide, Tlayúa is nowadays considered patrimony for the humanity. One of the most accepted hypothesis for explaining Tlayúa's formation relies on the deposition of sediments and fauna on a shallow platform of a tropical sea. A similar geographic place is located in Solenhofen, Germany, where slurries have been exploited for more than 200 yrs with a production of approximately 500 species. Remarkably, in the Tepexi del Rio region for the past 20 yrs more than 5,000 fossil specimens representing more than 200 species have been collected alone. An exceptional specimen preservation found in Tlayúa has been attributed to restricted circulation of water resulting in an anaerobic and/or hypersaline environment, coupled with the general absence of infaunal species. There were periods when the deposition site supported a rich planktontic community. Large quantities of calcareous ooze were produced, resulting in rapid burial of the organisms. The presence of diagnostic terrestrial and freshwater organisms, including arachnids, insects, lizards, and chelonians, along with typical marine fauna, suggests that Tlayúa lagoon had periodic freshwater inflow, in addition to the strong marine, lagoonal, and reefal influence. Some organisms were transported into the

New Insights in the Ontogeny and Taphonomy of the Devonian Acanthodian Triazeugacanthus affinis From the Miguasha Fossil-Lagerstätte, Eastern Canada

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Marion Chevrinais

2015-12-01

Full Text Available Progressive biomineralization of a skeleton occurs during ontogeny in most animals. In fishes, larvae are poorly mineralized, whereas juveniles and adults display a progressively more biomineralized skeleton. Fossil remains primarily consist of adult specimens because the fossilization of poorly-mineralized larvae and juveniles necessitates exceptional conditions. The Miguasha Fossil-Lagerstätte is renowned for its Late Devonian vertebrate fauna, revealing the exceptional preservation of fossilized ontogenies for 14 of the 20 fish species from this locality. The mineralization of anatomical structures of the acanthodian Triazeugacanthus affinis from Miguasha are compared among larval, juvenile and adult specimens using Energy Dispersive X-ray Spectrometry. Chemical composition of anatomical structures of Triazeugacanthus reveals differences between cartilage and bone. Although the histology and anatomy is well-preserved, Fourier transform infrared spectrometry shows that the original chemical composition of bone is altered by diagenesis; the mineral phase of the bone (i.e., hydroxyapatite is modified chemically to form more stable carbonate-fluorapatite. Fluorination occurring in mineralized skeletal structures of adult Triazeugacanthus is indicative of exchanges between groundwater and skeleton at burial, whereas the preservation of larval soft tissues is likely owing to a rapid burial under anoxic conditions. The exceptional state of preservation of a fossilized ontogeny allowed us to characterize chemically the progressive mineralization of the skeleton in a Devonian early vertebrate.

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

A geochemical study of the Ediacaran discoidal fossil Aspidella preserved in limestones: Implications for its taphonomy and paleoecology.

Science.gov (United States)

Bykova, N; Gill, B C; Grazhdankin, D; Rogov, V; Xiao, S

2017-07-01

The Ediacara biota features the rise of macroscopic complex life immediately before the Cambrian explosion. One of the most abundant and widely distributed elements of the Ediacara biota is the discoidal fossil Aspidella, which is interpreted as a subsurface holdfast possibly anchoring a frondose epibenthic organism. It is a morphologically simple fossil preserved mainly in siliciclastic rocks, which are unsuitable for comprehensive stable isotope geochemical analyses to decipher its taphonomy and paleoecology. In this regard, three-dimensionally preserved Aspidella fossils from upper Ediacaran limestones of the Khatyspyt Formation in the Olenek Uplift of northern Siberia offer a rare opportunity to leverage geochemistry for insights into their taphonomy and paleoecology. To take advantage of this opportunity, we analyzed δ 13 C carb , δ 18 O carb , δ 13 C org , δ 34 S pyr , and iron speciation of the Khatyspyt Aspidella fossils and surrounding sediment matrix in order to investigate whether they hosted microbial symbionts, how they were fossilized, and the redox conditions of their ecological environments. Aspidella holdfasts and surrounding sediment matrix show indistinguishable δ 13 C org values, suggesting they did not host and derive significant amount of nutrients from microbial symbionts such as methanogens, methylotrophs, or sulfide-oxidizing bacteria. δ 13 C carb , δ 18 O carb , and δ 34 S pyr data, along with petrographic observations, suggest that microbial sulfate reduction facilitated the preservation of Aspidella by promoting early authigenic calcite cementation in the holdfasts before matrix cementation and sediment compaction. Iron speciation data are equivocal, largely because of the low total iron concentrations. However, consideration of published sulfur isotope and biomarker data suggests that Aspidella likely lived in non-euxinic waters. It is possible that Aspidella was an opportunistic organism, colonizing the seafloor in large

Exceptionally preserved Cambrian trilobite digestive system revealed in 3D by synchrotron-radiation X-ray tomographic microscopy.

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Mats E Eriksson

Full Text Available The Cambrian 'Orsten' fauna comprises exceptionally preserved and phosphatised microscopic arthropods. The external morphology of these fossils is well known, but their internal soft-tissue anatomy has remained virtually unknown. Here, we report the first non-biomineralised tissues from a juvenile polymerid trilobite, represented by digestive structures, glands, and connective strands harboured in a hypostome from the Swedish 'Orsten' fauna. Synchrotron-radiation X-ray tomographic microscopy enabled three-dimensional internal recordings at sub-micrometre resolution. The specimen provides the first unambiguous evidence for a J-shaped anterior gut and the presence of a crop with a constricted alimentary tract in the Trilobita. Moreover, the gut is Y-shaped in cross section, probably due to a collapsed lumen of that shape, another feature which has not previously been observed in trilobites. The combination of anatomical features suggests that the trilobite hypostome is functionally analogous to the labrum of euarthropods and that it was a sophisticated element closely integrated with the digestive system. This study also briefly addresses the preservational bias of the 'Orsten' fauna, particularly the near-absence of polymerid trilobites, and the taphonomy of the soft-tissue-harbouring hypostome.

Preservation of Plant Biomolecules and the Relevance to the Interpretation of Paleoenvironmental Signals: Tertiary Metasequoia Fossils as Examples

Science.gov (United States)

Yang, H.; Leng, Q.

2004-12-01

The degradation and preservation of biomolecules in plant tissues not only affects the inference on paleoecology of ancient plants but also bears significance in the interpretation of paleoenvironmental signals. Using a combined SEM and geochemical approach, we are able to show the source, liability, and preservation of structural biopolymers from morphologically well-preserved Metasequoia tissues from three Tertiary deposits. We detected a continuum of biomolecular preservation in this evolutionarily-conserved conifer. Pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) was applied to solvent-extracted residues from both fossil leaf and wood remains in comparison with tissues from their living counterparts. The late Paleocene-early Eocene leaves from Ellesmere Island, Canadian Arctic Archipelago, exhibit the best quality of biochemical preservation and show pyrolysis products derived from labile biomolecules characterized by large amounts of polysaccharides. These labile biomolecules are the oldest record of these kinds so far characterized by the pyrolysis technology. The middle Eocene leaf tissues from Axel Heiberg Island, Canadian Arctic Archipelago, yielded slightly lesser amounts of polysaccharide moieties, but the lignin products are similar to those identified from the Ellesmere Island fossils. Compared with these Arctic materials, the Metasequoia leaves from Miocene Clarkia, Idaho, USA, show the lowest quality of molecular preservation, characterized by a dramatic reduction of polysaccharides. This continuum of relative quality of biomolecular preservation is further confirmed by SEM observations of transverse sections of these fossil leaves. The investigation revealed tissue-specific degradation, and our data support the in-situ polymerization hypothesis for the origin of long-chain homologous pairs of aliphatic n-alk-1-enes/n-alkanes as leaf alteration products. The preferential degradation and selective removal of polysaccharides may be

An exceptionally preserved Eocene shark and the rise of modern predator-prey interactions in the coral reef food web.

Science.gov (United States)

Fanti, Federico; Minelli, Daniela; Conte, Gabriele Larocca; Miyashita, Tetsuto

2016-01-01

Following extreme climatic warming events, Eocene Lagerstätten document aquatic and terrestrial vertebrate faunas surprisingly similar to modern counterparts. This transition in marine systems is best documented in the earliest teleost-dominated coral reef assemblage of Pesciara di Bolca, northern Italy, from near the end of the Eocene Climatic Optimum. Its rich fauna shows similarities with that of the modern Great Barrier Reef in niche exploitation by and morphological disparity among teleost primary consumers. However, such paleoecological understanding has not transcended trophic levels above primary consumers, particularly in carcharhiniform sharks. We report an exceptionally preserved fossil school shark (Galeorhinus cuvieri) from Pesciara di Bolca. In addition to the spectacular preservation of soft tissues, including brain, muscles, and claspers, this male juvenile shark has stomach contents clearly identifiable as a sphyraenid acanthomorph (barracuda). This association provides evidence that a predator-prey relationship between Galeorhinus and Sphyraena in the modern coral reefs has roots in the Eocene. A growth curve of the living species of Galeorhinus fitted to G. cuvieri suggests that all specimens of G. cuvieri from the lagoonal deposits of Bolca represent sexually and somatically immature juveniles. The modern trophic association between higher-degree consumers (Galeorhinus and Sphyraena) has a counterpart in the Eocene Bolca, just as Bolca and the Great Barrier Reef show parallels among teleost primary consumers. Given the age of Bolca, trophic networks among consumers observed in modern coral reefs arose by the exit from the Climatic Optimum. The biased representation of juveniles suggests that the Bolca Lagerstätte served as a nursery habitat for G. cuvieri. Ultraviolet photography may be useful in probing for exceptional soft tissue preservation before common acid preparation methods.

The original colours of fossil beetles.

Science.gov (United States)

McNamara, Maria E; Briggs, Derek E G; Orr, Patrick J; Noh, Heeso; Cao, Hui

2012-03-22

Structural colours, the most intense, reflective and pure colours in nature, are generated when light is scattered by complex nanostructures. Metallic structural colours are widespread among modern insects and can be preserved in their fossil counterparts, but it is unclear whether the colours have been altered during fossilization, and whether the absence of colours is always real. To resolve these issues, we investigated fossil beetles from five Cenozoic biotas. Metallic colours in these specimens are generated by an epicuticular multi-layer reflector; the fidelity of its preservation correlates with that of other key cuticular ultrastructures. Where these other ultrastructures are well preserved in non-metallic fossil specimens, we can infer that the original cuticle lacked a multi-layer reflector; its absence in the fossil is not a preservational artefact. Reconstructions of the original colours of the fossils based on the structure of the multi-layer reflector show that the preserved colours are offset systematically to longer wavelengths; this probably reflects alteration of the refractive index of the epicuticle during fossilization. These findings will allow the former presence, and original hue, of metallic structural colours to be identified in diverse fossil insects, thus providing critical evidence of the evolution of structural colour in this group.

Preservation of uropygial gland lipids in a 48-million-year-old bird.

Science.gov (United States)

O'Reilly, Shane; Summons, Roger; Mayr, Gerald; Vinther, Jakob

2017-10-25

Although various kinds of organic molecules are known to occur in fossils and rocks, most soft tissue preservation in animals is attributed to melanin or porphyrins. Lipids are particularly stable over time-as diagenetically altered 'geolipids' or as major molecular constituents of kerogen or fossil 'geopolymers'-and may be expected to be preserved in certain vertebrate tissues. Here we analysed lipid residues from the uropygial gland of an early Eocene bird using pyrolysis gas chromatography mass spectroscopy. We found a pattern of aliphatic molecules in the fossil gland that was distinct from the host oil shale sediment matrix and from feathers of the same fossil. The fossil gland contained abundant n -alkenes, n -alkanes and alkylbenzenes with chain lengths greater than 20, as well as functionalized long-chain aldehydes, ketones, alkylnitriles and alkylthiophenes that were not detected in host sediment or fossil feathers. By comparison with modern bird uropygial gland wax esters, we show that these molecular fossils are likely derived from endogenous wax ester fatty alcohols and fatty acids that survived initial decay and underwent early diagenetic geopolymerization. These data demonstrate the high fidelity preservation of the uropygial gland waxes and showcase the resilience of lipids over geologic time and their potential role in the exceptional preservation of lipid-rich tissues of macrofossils. © 2017 The Author(s).

Absence of ancient DNA in sub-fossil insect inclusions preserved in 'Anthropocene' Colombian copal.

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David Penney

Full Text Available Insects preserved in copal, the sub-fossilized resin precursor of amber, have potential value in molecular ecological studies of recently-extinct species and of extant species that have never been collected as living specimens. The objective of the work reported in this paper was therefore to determine if ancient DNA is present in insects preserved in copal. We prepared DNA libraries from two stingless bees (Apidae: Meliponini: Trigonisca ameliae preserved in 'Anthropocene' Colombian copal, dated to 'post-Bomb' and 10,612±62 cal yr BP, respectively, and obtained sequence reads using the GS Junior 454 System. Read numbers were low, but were significantly higher for DNA extracts prepared from crushed insects compared with extracts obtained by a non-destructive method. The younger specimen yielded sequence reads up to 535 nucleotides in length, but searches of these sequences against the nucleotide database revealed very few significant matches. None of these hits was to stingless bees though one read of 97 nucleotides aligned with two non-contiguous segments of the mitochondrial cytochrome oxidase subunit I gene of the East Asia bumblebee Bombus hypocrita. The most significant hit was for 452 nucleotides of a 470-nucleotide read that aligned with part of the genome of the root-nodulating bacterium Bradyrhizobium japonicum. The other significant hits were to proteobacteria and an actinomycete. Searches directed specifically at Apidae nucleotide sequences only gave short and insignificant alignments. All of the reads from the older specimen appeared to be artefacts. We were therefore unable to obtain any convincing evidence for the preservation of ancient DNA in either of the two copal inclusions that we studied, and conclude that DNA is not preserved in this type of material. Our results raise further doubts about claims of DNA extraction from fossil insects in amber, many millions of years older than copal.

Fossilization processes in siliceous thermal springs: trends in preservation along thermal gradients

Science.gov (United States)

Cady, S. L.; Farmer, J. D.

1996-01-01

To enhance our ability to extract palaeobiological and palaeoenvironmental information from ancient thermal spring deposits, we have studied the processes responsible for the development and preservation of stromatolites in modern subaerial thermal spring systems in Yellowstone National Park (USA). We investigated specimens collected from silica-depositing thermal springs along the thermal gradient using petrographic techniques and scanning electron microscopy. Although it is known that thermophilic cyanobacteria control the morphogenesis of thermal spring stromatolites below 73 degrees C, we have found that biofilms which contain filamentous thermophiles contribute to the microstructural development of subaerial geyserites that occur along the inner rims of thermal spring pools and geyser effluents. Biofilms intermittently colonize the surfaces of subaerial geyserites and provide a favoured substrate for opaline silica precipitation. We have also found that the preservation of biotically produced microfabrics of thermal spring sinters reflects dynamic balances between rates of population growth, decomposition of organic matter, silica deposition and early diagenesis. Major trends in preservation of thermophilic organisms along the thermal gradient are defined by differences in the mode of fossilization, including replacement, encrustation and permineralization.

The fossil Osmundales (Royal Ferns—a phylogenetic network analysis, revised taxonomy, and evolutionary classification of anatomically preserved trunks and rhizomes

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Benjamin Bomfleur

2017-07-01

Full Text Available The Osmundales (Royal Fern order originated in the late Paleozoic and is the most ancient surviving lineage of leptosporangiate ferns. In contrast to its low diversity today (less than 20 species in six genera, it has the richest fossil record of any extant group of ferns. The structurally preserved trunks and rhizomes alone are referable to more than 100 fossil species that are classified in up to 20 genera, four subfamilies, and two families. This diverse fossil record constitutes an exceptional source of information on the evolutionary history of the group from the Permian to the present. However, inconsistent terminology, varying formats of description, and the general lack of a uniform taxonomic concept renders this wealth of information poorly accessible. To this end, we provide a comprehensive review of the diversity of structural features of osmundalean axes under a standardized, descriptive terminology. A novel morphological character matrix with 45 anatomical characters scored for 15 extant species and for 114 fossil operational units (species or specimens is analysed using networks in order to establish systematic relationships among fossil and extant Osmundales rooted in axis anatomy. The results lead us to propose an evolutionary classification for fossil Osmundales and a revised, standardized taxonomy for all taxa down to the rank of (subgenus. We introduce several nomenclatural novelties: (1 a new subfamily Itopsidemoideae (Guaireaceae is established to contain Itopsidema, Donwelliacaulis, and Tiania; (2 the thamnopteroid genera Zalesskya, Iegosigopteris, and Petcheropteris are all considered synonymous with Thamnopteris; (3 12 species of Millerocaulis and Ashicaulis are assigned to modern genera (tribe Osmundeae; (4 the hitherto enigmatic Aurealcaulis is identified as an extinct subgenus of Plenasium; and (5 the poorly known Osmundites tuhajkulensis is assigned to Millerocaulis. In addition, we consider Millerocaulis

The fossil Osmundales (Royal Ferns)-a phylogenetic network analysis, revised taxonomy, and evolutionary classification of anatomically preserved trunks and rhizomes.

Science.gov (United States)

Bomfleur, Benjamin; Grimm, Guido W; McLoughlin, Stephen

2017-01-01

The Osmundales (Royal Fern order) originated in the late Paleozoic and is the most ancient surviving lineage of leptosporangiate ferns. In contrast to its low diversity today (less than 20 species in six genera), it has the richest fossil record of any extant group of ferns. The structurally preserved trunks and rhizomes alone are referable to more than 100 fossil species that are classified in up to 20 genera, four subfamilies, and two families. This diverse fossil record constitutes an exceptional source of information on the evolutionary history of the group from the Permian to the present. However, inconsistent terminology, varying formats of description, and the general lack of a uniform taxonomic concept renders this wealth of information poorly accessible. To this end, we provide a comprehensive review of the diversity of structural features of osmundalean axes under a standardized, descriptive terminology. A novel morphological character matrix with 45 anatomical characters scored for 15 extant species and for 114 fossil operational units (species or specimens) is analysed using networks in order to establish systematic relationships among fossil and extant Osmundales rooted in axis anatomy. The results lead us to propose an evolutionary classification for fossil Osmundales and a revised, standardized taxonomy for all taxa down to the rank of (sub)genus. We introduce several nomenclatural novelties: (1) a new subfamily Itopsidemoideae (Guaireaceae) is established to contain Itopsidema , Donwelliacaulis , and Tiania ; (2) the thamnopteroid genera Zalesskya , Iegosigopteris , and Petcheropteris are all considered synonymous with Thamnopteris ; (3) 12 species of Millerocaulis and Ashicaulis are assigned to modern genera (tribe Osmundeae); (4) the hitherto enigmatic Aurealcaulis is identified as an extinct subgenus of Plenasium ; and (5) the poorly known Osmundites tuhajkulensis is assigned to Millerocaulis . In addition, we consider Millerocaulis

Trace elemental imaging of rare earth elements discriminates tissues at microscale in flat fossils.

Science.gov (United States)

Gueriau, Pierre; Mocuta, Cristian; Dutheil, Didier B; Cohen, Serge X; Thiaudière, Dominique; Charbonnier, Sylvain; Clément, Gaël; Bertrand, Loïc

2014-01-01

The interpretation of flattened fossils remains a major challenge due to compression of their complex anatomies during fossilization, making critical anatomical features invisible or hardly discernible. Key features are often hidden under greatly preserved decay prone tissues, or an unpreparable sedimentary matrix. A method offering access to such anatomical features is of paramount interest to resolve taxonomic affinities and to study fossils after a least possible invasive preparation. Unfortunately, the widely-used X-ray micro-computed tomography, for visualizing hidden or internal structures of a broad range of fossils, is generally inapplicable to flattened specimens, due to the very high differential absorbance in distinct directions. Here we show that synchrotron X-ray fluorescence spectral raster-scanning coupled to spectral decomposition or a much faster Kullback-Leibler divergence based statistical analysis provides microscale visualization of tissues. We imaged exceptionally well-preserved fossils from the Late Cretaceous without needing any prior delicate preparation. The contrasting elemental distributions greatly improved the discrimination of skeletal elements material from both the sedimentary matrix and fossilized soft tissues. Aside content in alkaline earth elements and phosphorus, a critical parameter for tissue discrimination is the distinct amounts of rare earth elements. Local quantification of rare earths may open new avenues for fossil description but also in paleoenvironmental and taphonomical studies.

The fossil Osmundales (Royal Ferns)—a phylogenetic network analysis, revised taxonomy, and evolutionary classification of anatomically preserved trunks and rhizomes

Science.gov (United States)

2017-01-01

The Osmundales (Royal Fern order) originated in the late Paleozoic and is the most ancient surviving lineage of leptosporangiate ferns. In contrast to its low diversity today (less than 20 species in six genera), it has the richest fossil record of any extant group of ferns. The structurally preserved trunks and rhizomes alone are referable to more than 100 fossil species that are classified in up to 20 genera, four subfamilies, and two families. This diverse fossil record constitutes an exceptional source of information on the evolutionary history of the group from the Permian to the present. However, inconsistent terminology, varying formats of description, and the general lack of a uniform taxonomic concept renders this wealth of information poorly accessible. To this end, we provide a comprehensive review of the diversity of structural features of osmundalean axes under a standardized, descriptive terminology. A novel morphological character matrix with 45 anatomical characters scored for 15 extant species and for 114 fossil operational units (species or specimens) is analysed using networks in order to establish systematic relationships among fossil and extant Osmundales rooted in axis anatomy. The results lead us to propose an evolutionary classification for fossil Osmundales and a revised, standardized taxonomy for all taxa down to the rank of (sub)genus. We introduce several nomenclatural novelties: (1) a new subfamily Itopsidemoideae (Guaireaceae) is established to contain Itopsidema, Donwelliacaulis, and Tiania; (2) the thamnopteroid genera Zalesskya, Iegosigopteris, and Petcheropteris are all considered synonymous with Thamnopteris; (3) 12 species of Millerocaulis and Ashicaulis are assigned to modern genera (tribe Osmundeae); (4) the hitherto enigmatic Aurealcaulis is identified as an extinct subgenus of Plenasium; and (5) the poorly known Osmundites tuhajkulensis is assigned to Millerocaulis. In addition, we consider Millerocaulis stipabonettiorum a

The shape of pterosaur evolution: evidence from the fossil record.

Science.gov (United States)

Dyke, G J; McGowan, A J; Nudds, R L; Smith, D

2009-04-01

Although pterosaurs are a well-known lineage of Mesozoic flying reptiles, their fossil record and evolutionary dynamics have never been adequately quantified. On the basis of a comprehensive data set of fossil occurrences correlated with taxon-specific limb measurements, we show that the geological ages of pterosaur specimens closely approximate hypothesized patterns of phylogenetic divergence. Although the fossil record has expanded greatly in recent years, collectorship still approximates a sigmoid curve over time as many more specimens (and thus taxa) still remain undiscovered, yet our data suggest that the pterosaur fossil record is unbiased by sites of exceptional preservation (lagerstätte). This is because as new species are discovered the number of known formations and sites yielding pterosaur fossils has also increased - this would not be expected if the bulk of the record came from just a few exceptional faunas. Pterosaur morphological diversification is, however, strongly age biased: rarefaction analysis shows that peaks of diversity occur in the Late Jurassic and Early Cretaceous correlated with periods of increased limb disparity. In this respect, pterosaurs appear unique amongst flying vertebrates in that their disparity seems to have peaked relatively late in clade history. Comparative analyses also show that there is little evidence that the evolutionary diversification of pterosaurs was in any way constrained by the appearance and radiation of birds.

When a 520 million-year-old Chengjiang fossil meets a modern micro-CT--a case study.

Science.gov (United States)

Liu, Yu; Scholtz, Gerhard; Hou, Xianguang

2015-08-04

The 520 million-year-old Chengjiang biota of China (UNESCO World Heritage) presents the earliest known evidence of the so-called Cambrian Explosion. Studies, however, have mainly been limited to the information exposed on the surface of the slabs. Thus far, structures preserved inside the slabs were accessed by careful removal of the matrix, in many cases with the unfortunate sacrifice of some "less important" structures, which destroys elements of exceptionally preserved specimens. Here, we show for the first time that microtomography (micro-CT) can reveal structures situated inside a Chengjiang fossil slab without causing any damage. In the present study a trilobitomorph arthropod (Xandarella spectaculum) can be reliably identified only with the application of micro-CT. We propose that this technique is an important tool for studying three-dimensionally preserved Chengjiang fossils and, most likely, also those from other biota with a comparable type of preservation, specifically similar iron concentrations.

The fossil Osmundales (Royal Ferns)—a phylogenetic network analysis, revised taxonomy, and evolutionary classification of anatomically preserved trunks and rhizomes

OpenAIRE

Benjamin Bomfleur; Guido W. Grimm; Stephen McLoughlin

2017-01-01

The Osmundales (Royal Fern order) originated in the late Paleozoic and is the most ancient surviving lineage of leptosporangiate ferns. In contrast to its low diversity today (less than 20 species in six genera), it has the richest fossil record of any extant group of ferns. The structurally preserved trunks and rhizomes alone are referable to more than 100 fossil species that are classified in up to 20 genera, four subfamilies, and two families. This diverse fossil record constitutes an exce...

New record of a fossil haplotilapiine cichlid from Central Kenya

Directory of Open Access Journals (Sweden)

Stefanie B. R. Penk

2015-11-01

Full Text Available African freshwater cichlids (Cichlidae: Pseudocrenilabrinae are well known for their exceptionally great diversity and their capability of rapid speciation as well as diverse adaptations. The extant Pseudocrenilabrinae can be grouped into 27 tribes, with more than 2000 species harbored in the Great Lakes and surrounding water bodies of the East African Rift System. However, this unique diversity is not reflected in the fossil record because fossil cichlids were predominantly reported based on isolated teeth and bones. Moreover, the few articulated specimens that are known have not been analyzed sufficiently with regard to their systematic position due to lack of comparative material. Here we present a new extraordinarily well-preserved cichlid fish fossil from the Middle Miocene (c. 12.5 Ma Lagerstaette Kabchore, which was recovered during recent fieldwork in the Tugen Hills (Baringo County, Central Kenya Rift. Based on the evidence of tricuspid teeth, the Kabchore fossil can be assigned to the subclade of the Haplotilapiines within the Pseudocrenilabrinae. The multivariate analysis of a large meristic data set, derived from 1014 extant specimens (encompassing all main lineages of Haplotilapiines and usage of available osteological data suggest that this fossil is most likely related to one of the three haplotilapiine tribes Tilapiini, Haplochromini or Oreochromini. Moreover, the fossil specimen closely resembles the extinct cichlid Oreochromis martyni (Van Couvering, 1982, previously described as species of Sarotherodon from the Middle Miocene alkaline Kapkiamu Lake in the Tugen Hills. The analysis of the greatly preserved fossil fish specimen from Kabchore definitely supplements the fragmentary fossil record of Africa’s Cichlidae and will afford new insights into its evolutionary history. We also expect that this fossil will be useful as calibration point for new divergence-time estimates.

Preserved microstructure and mineral distribution in tooth and periodontal tissues in early fossil hominin material from Koobi Fora, Kenya.

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Klinge, R Furseth; Dean, M C; Risnes, S; Erambert, M; Gunnaes, A E

2009-01-01

The aim of this study was to explore further the preservation of tissues and the mineral distribution in 1.6 million-year-old fossil hominin material from Koobi Fora, Kenya attributed to Paranthropus boisei (KNM-ER 1817). Bone, dentine and cementum microstructure were well preserved. Electron microprobe analysis of dentine and bone revealed an F-bearing apatite. Calcite now filled the original soft tissue spaces. The average Ca/P atomic ratio was 1.93, as compared to 1.67 in biological hydroxyapatite, indicating that the Ca-content had increased during fossilization. Analytical sums for mineral content were approximately 90 wt%. Some of the remaining 10 wt% may be preserved organic material. Demineralized dentine fragments showed irregularly distributed tubules encircled with a fibrous-like electron-dense material. A similar material was observed in demineralized dentine. Within this, structures resembling bacteria were seen. In demineralized bone an electron-dense material with a fibrous appearance and a banding pattern that repeated every 64 nm, similar to that of collagen, was noted. SEM of an enamel fragment (KNM-ER 6081) showed signs of demineralization/remineralization. Retzius lines, Hunter-Schreger bands and prism cross-striations spaced 3.7-7.1.microm apart were noted. Prisms were arranged in a pattern 3 configuration and deeper areas containing aprismatic enamel were occasionally observed. We conclude that a great deal of informative microstructure and ultrastructure remains preserved in this fossil material. We also hypothesize that the high mineral content of the tissues may 'protect' parts of the organic matrix from degradation, since our findings indicate that some organic matrix may still be present. Copyright (c) 2009 S. Karger AG, Basel.

Trace elemental imaging of rare earth elements discriminates tissues at microscale in flat fossils.

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Pierre Gueriau

Full Text Available The interpretation of flattened fossils remains a major challenge due to compression of their complex anatomies during fossilization, making critical anatomical features invisible or hardly discernible. Key features are often hidden under greatly preserved decay prone tissues, or an unpreparable sedimentary matrix. A method offering access to such anatomical features is of paramount interest to resolve taxonomic affinities and to study fossils after a least possible invasive preparation. Unfortunately, the widely-used X-ray micro-computed tomography, for visualizing hidden or internal structures of a broad range of fossils, is generally inapplicable to flattened specimens, due to the very high differential absorbance in distinct directions. Here we show that synchrotron X-ray fluorescence spectral raster-scanning coupled to spectral decomposition or a much faster Kullback-Leibler divergence based statistical analysis provides microscale visualization of tissues. We imaged exceptionally well-preserved fossils from the Late Cretaceous without needing any prior delicate preparation. The contrasting elemental distributions greatly improved the discrimination of skeletal elements material from both the sedimentary matrix and fossilized soft tissues. Aside content in alkaline earth elements and phosphorus, a critical parameter for tissue discrimination is the distinct amounts of rare earth elements. Local quantification of rare earths may open new avenues for fossil description but also in paleoenvironmental and taphonomical studies.

Bias and sensitivity in the placement of fossil taxa resulting from interpretations of missing data.

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Sansom, Robert S

2015-03-01

The utility of fossils in evolutionary contexts is dependent on their accurate placement in phylogenetic frameworks, yet intrinsic and widespread missing data make this problematic. The complex taphonomic processes occurring during fossilization can make it difficult to distinguish absence from non-preservation, especially in the case of exceptionally preserved soft-tissue fossils: is a particular morphological character (e.g., appendage, tentacle, or nerve) missing from a fossil because it was never there (phylogenetic absence), or just happened to not be preserved (taphonomic loss)? Missing data have not been tested in the context of interpretation of non-present anatomy nor in the context of directional shifts and biases in affinity. Here, complete taxa, both simulated and empirical, are subjected to data loss through the replacement of present entries (1s) with either missing (?s) or absent (0s) entries. Both cause taxa to drift down trees, from their original position, toward the root. Absolute thresholds at which downshift is significant are extremely low for introduced absences (two entries replaced, 6% of present characters). The opposite threshold in empirical fossil taxa is also found to be low; two absent entries replaced with presences causes fossil taxa to drift up trees. As such, only a few instances of non-preserved characters interpreted as absences will cause fossil organisms to be erroneously interpreted as more primitive than they were in life. This observed sensitivity to coding non-present morphology presents a problem for all evolutionary studies that attempt to use fossils to reconstruct rates of evolution or unlock sequences of morphological change. Stem-ward slippage, whereby fossilization processes cause organisms to appear artificially primitive, appears to be a ubiquitous and problematic phenomenon inherent to missing data, even when no decay biases exist. Absent characters therefore require explicit justification and taphonomic

Fossil cyclanthus (cyclanthaceae, pandanales) from the eocene of Germany and England.

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Smith, Selena Y; Collinson, Margaret E; Rudall, Paula J

2008-06-01

The first known fossil fruits and seeds of Cyclanthaceae are described here. Cyclanthus messelensis sp. nov., from the Middle Eocene of Messel, Germany, has discoidal fruiting cycles up to 6 cm in diameter, with a central hole, radiating fiber strands, a thickened outer rim, and paratetracytic stomata. In situ seeds are up to 2 mm long, with an elongate micropylar end, a chalazal neck, and adpressed bands. The Messel fruits and seeds are nearly identical to those of Cyclanthus, differing in minor details of cuticular structure and seeds. The exceptional preservation at Messel (including in situ and isolated seeds) has also allowed us to establish the taxonomic affinity of isolated seeds ('Scirpus' lakensis) that are spatially and temporally widespread in the late Early and early Middle Eocene of southern England. Cyclanthus lakensis comb. nov. is described here as a morphotaxon for isolated fossil Cyclanthus seeds, preserved only as cuticular envelopes. Cyclanthus is another example of links between Eocene Europe and Recent South American floras because it is found today only from Mexico to South America. This material represents the first fossil fruits and seeds of Cyclanthus, which clearly was once growing in the Paleogene of the Old World.

Exceptional preservation of eye structure in arthropod visual predators from the Middle Jurassic.

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Vannier, Jean; Schoenemann, Brigitte; Gillot, Thomas; Charbonnier, Sylvain; Clarkson, Euan

2016-01-19

Vision has revolutionized the way animals explore their environment and interact with each other and rapidly became a major driving force in animal evolution. However, direct evidence of how ancient animals could perceive their environment is extremely difficult to obtain because internal eye structures are almost never fossilized. Here, we reconstruct with unprecedented resolution the three-dimensional structure of the huge compound eye of a 160-million-year-old thylacocephalan arthropod from the La Voulte exceptional fossil biota in SE France. This arthropod had about 18,000 lenses on each eye, which is a record among extinct and extant arthropods and is surpassed only by modern dragonflies. Combined information about its eyes, internal organs and gut contents obtained by X-ray microtomography lead to the conclusion that this thylacocephalan arthropod was a visual hunter probably adapted to illuminated environments, thus contradicting the hypothesis that La Voulte was a deep-water environment.

When a 520 million-year-old Chengjiang fossil meets a modern micro-CT – a case study

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Liu, Yu; Scholtz, Gerhard; Hou, Xianguang

2015-01-01

The 520 million-year-old Chengjiang biota of China (UNESCO World Heritage) presents the earliest known evidence of the so-called Cambrian Explosion. Studies, however, have mainly been limited to the information exposed on the surface of the slabs. Thus far, structures preserved inside the slabs were accessed by careful removal of the matrix, in many cases with the unfortunate sacrifice of some “less important” structures, which destroys elements of exceptionally preserved specimens. Here, we show for the first time that microtomography (micro-CT) can reveal structures situated inside a Chengjiang fossil slab without causing any damage. In the present study a trilobitomorph arthropod (Xandarella spectaculum) can be reliably identified only with the application of micro-CT. We propose that this technique is an important tool for studying three-dimensionally preserved Chengjiang fossils and, most likely, also those from other biota with a comparable type of preservation, specifically similar iron concentrations. PMID:26238773

An exceptionally preserved Late Devonian actinopterygian provides a new model for primitive cranial anatomy in ray-finned fishes

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Giles, Sam; Darras, Laurent; Clément, Gaël; Blieck, Alain; Friedman, Matt

2015-01-01

Actinopterygians (ray-finned fishes) are the most diverse living osteichthyan (bony vertebrate) group, with a rich fossil record. However, details of their earliest history during the middle Palaeozoic (Devonian) ‘Age of Fishes' remains sketchy. This stems from an uneven understanding of anatomy in early actinopterygians, with a few well-known species dominating perceptions of primitive conditions. Here we present an exceptionally preserved ray-finned fish from the Late Devonian (Middle Frasnian, ca 373 Ma) of Pas-de-Calais, northern France. This new genus is represented by a single, three-dimensionally preserved skull. CT scanning reveals the presence of an almost complete braincase along with near-fully articulated mandibular, hyoid and gill arches. The neurocranium differs from the coeval Mimipiscis in displaying a short aortic canal with a distinct posterior notch, long grooves for the lateral dorsal aortae, large vestibular fontanelles and a broad postorbital process. Identification of similar but previously unrecognized features in other Devonian actinopterygians suggests that aspects of braincase anatomy in Mimipiscis are apomorphic, questioning its ubiquity as stand-in for generalized actinopterygian conditions. However, the gill skeleton of the new form broadly corresponds to that of Mimipiscis, and adds to an emerging picture of primitive branchial architecture in crown gnathostomes. The new genus is recovered in a polytomy with Mimiidae and a subset of Devonian and stratigraphically younger actinopterygians, with no support found for a monophyletic grouping of Moythomasia with Mimiidae. PMID:26423841

Microscopical and elemental FESEM and Phenom ProX-SEM-EDS analysis of osteocyte- and blood vessel-like microstructures obtained from fossil vertebrates of the Eocene Messel Pit, Germany.

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Cadena, Edwin

2016-01-01

The Eocene (∾48 Ma) Messel Pit in Germany is a UNESCO World Heritage Site because of its exceptionally preserved fossils, including vertebrates, invertebrates, and plants. Messel fossil vertebrates are typically characterized by their articulated state, and in some cases the skin, hair, feathers, scales and stomach contents are also preserved. Despite the exceptional macroscopic preservation of Messel fossil vertebrates, the microstructural aspect of these fossils has been poorly explored. In particular, soft tissue structures such as hair or feathers have not been chemically analyzed, nor have bone microstructures. I report here the preservation and recovery of osteocyte-like and blood vessel-like microstructures from the bone of Messel Pit specimens, including the turtles Allaeochelys crassesculpta and Neochelys franzeni, the crocodile Diplocynodon darwini, and the pangolin Eomanis krebsi. I used a Field Emission Scanning Electron Microscope (FESEM) and a Phenom ProX desktop scanning electron microscope (LOT-QuantumDesign) equipped with a thermionic CeB6 source and a high sensitivity multi-mode backscatter electron (BSE) for microscopical and elemental characterization of these bone microstructures. Osteocyte-like and blood vessel-like microstructures are constituted by a thin layer (∾50 nm thickness), external and internal mottled texture with slightly marked striations. Circular to linear marks are common on the external surface of the osteocyte-like microstructures and are interpreted as microbial troughs. Iron (Fe) is the most abundant element found in the osteocyte-like and blood vessel-like microstructures, but not in the bone matrix or collagen fibril-like microstructures. The occurrence of well-preserved soft-tissue elements (at least their physical form) establishes a promising background for future studies on preservation of biomolecules (proteins or DNA) in Messel Pit fossils.

Microscopical and elemental FESEM and Phenom ProX-SEM-EDS analysis of osteocyte- and blood vessel-like microstructures obtained from fossil vertebrates of the Eocene Messel Pit, Germany

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Edwin Cadena

2016-01-01

Full Text Available The Eocene (∾48 Ma Messel Pit in Germany is a UNESCO World Heritage Site because of its exceptionally preserved fossils, including vertebrates, invertebrates, and plants. Messel fossil vertebrates are typically characterized by their articulated state, and in some cases the skin, hair, feathers, scales and stomach contents are also preserved. Despite the exceptional macroscopic preservation of Messel fossil vertebrates, the microstructural aspect of these fossils has been poorly explored. In particular, soft tissue structures such as hair or feathers have not been chemically analyzed, nor have bone microstructures. I report here the preservation and recovery of osteocyte-like and blood vessel-like microstructures from the bone of Messel Pit specimens, including the turtles Allaeochelys crassesculpta and Neochelys franzeni, the crocodile Diplocynodon darwini, and the pangolin Eomanis krebsi. I used a Field Emission Scanning Electron Microscope (FESEM and a Phenom ProX desktop scanning electron microscope (LOT-QuantumDesign equipped with a thermionic CeB6 source and a high sensitivity multi-mode backscatter electron (BSE for microscopical and elemental characterization of these bone microstructures. Osteocyte-like and blood vessel-like microstructures are constituted by a thin layer (∾50 nm thickness, external and internal mottled texture with slightly marked striations. Circular to linear marks are common on the external surface of the osteocyte-like microstructures and are interpreted as microbial troughs. Iron (Fe is the most abundant element found in the osteocyte-like and blood vessel-like microstructures, but not in the bone matrix or collagen fibril-like microstructures. The occurrence of well-preserved soft-tissue elements (at least their physical form establishes a promising background for future studies on preservation of biomolecules (proteins or DNA in Messel Pit fossils.

Fossil Crinoids

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Hess, Hans; Ausich, William I.; Brett, Carlton E.; Simms, Michael J.

2003-01-01

Crinoids have graced the oceans for more than 500 million years. Among the most attractive fossils, crinoids had a key role in the ecology of marine communities through much of the fossil record, and their remains are prominent rock forming constituents of many limestones. This is the first comprehensive volume to bring together their form and function, classification, evolutionary history, occurrence, preservation and ecology. The main part of the book is devoted to assemblages of intact fossil crinoids, which are described in their geological setting in twenty-three chapters ranging from the Ordovician to the Tertiary. The final chapter deals with living sea lilies and feather stars. The volume is exquisitely illustrated with abundant photographs and line drawings of crinoids from sites around the world. This authoritative account recreates a fascinating picture of fossil crinoids for paleontologists, geologists, evolutionary and marine biologists, ecologists and amateur fossil collectors.

Similarities between several major extinctions and preservation of life - biomolecules to geomolecules: an interdisciplinary approach

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Grice, Kliti; Melendez, Ines; Tulipani, Svenja

2015-04-01

WA Organic and Isotope Geochemistry Centre, The Institute for Geoscience Research, Department of Chemistry, Curtin University, GPO Box U1987 Perth, WA 6845, Australia Photic zone euxinia in ancient seas has proven signficant for elucidating biogeochemical changes that occurred during three of the five Phanerozoic mass extinctions, viz. the Permian/Triassic [1], Triassic/Jurassic [2] and Late Givetian (Devonian) [3] events, including the conditions associated with exceptional fossil preservation [4,5]. The series of events preceding, during and post the Triassic/Jurassic event, is remarkably similar to that reported for the Permian/Triassic extinction, the largest of the Phanerozoic Era. For the Late Givetian event, the first forests evolved and reef-building communities and associated fauna in tropical, marine settings were largely affected [6]. Sedimentary rocks on the margins of the Devonian reef slope in the Canning Basin, WA, contain novel biomarker, isotopic and palynological evidence for the existence of a persistently stratified water-column (comprising a freshwater lens overlying a more saline hypolimnion), with prevailing anoxia and PZE [7]. Also from the Canning Basin, the exceptional preservation of a suite of biomarkers in a Devonian invertebrate fossil within a carbonate concretion supports rapid encasement of the crustacean (identified by % of C27 steroids) enhanced by sulfate reducing bacteria under PZE conditions. PZE plays a critical role in fossil (including soft tissue) and biomarker preservation. In the same sample, the oldest occurrence of intact sterols shows that they have been preserved for ca. 380 Ma [5]. The exceptional preservation of this biomass is attributed to microbially induced carbonate encapsulation, preventing full decomposition and transformation, thus extending the record of sterol occurrences in the geosphere by 250 Ma. A suite of ca. 50 diagenetic transformation products of sterols is also reported, showing the unique

A new fossil cichlid from the Middle Miocene in the East African Rift Valley (Tugen Hills, Central Kenya: First record of a putative Ectodini

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Melanie Altner

2015-11-01

Full Text Available Identification of fossil cichlids is difficult, because the currently used diagnostic morphological characters for living cichlids are mostly soft tissue based and such characters are hardly preserved in fossils. During our recent fieldwork in the Central Kenya Rift (E-Africa, we discovered several exceptionally well-preserved fossil cichlids, which can be assigned to different lineages among the African Pseudocrenilabrinae. Here we present one of those new specimens. Its most conspicuous character is a lateral line divided into three segments. This specimen was found in the lacustrine sediments of the Middle Miocene site Waril, Tugen Hills, Kenya. The site represents the deposits of an ancient freshwater lake ca. 9-10 million years ago. Previous work on fossil leaves from the same site allow for the reconstruction of open vegetation surrounding the lake and pronounced dry seasons. Among the main further characteristics of the new fossil cichlid is a lachrimal with six lateral line canals, big cycloid scales and a low number of dorsal fin spines (XIII. The latter two characters are traceable in several members of tribes within the Pseudocrenilabrinae. However, a lachrimal with six lateral line canals is exclusively found in certain tribes of the EAR (East African Radiation within the Pseudocrenilabrinae. Moreover, the unique lateral line pattern is solely present in two genera of the EAR tribe Ectodini. However, the fossil shows cycloid scales, while modern Ectodini have ctenoid scales. Taken all evidence together, this fossil may perhaps represent an ancient lineage related to the Ectodini. Up to date, there is no definite fossil record of the members of the EAR. Our fossil may represent the first reliable calibration point for this group, which would be consistent with the previously reconstructed diversification time of the H-lineage (EAR tribes, except Boulengerochromini, Bathybatini, Trematocarini and Lamprologini and the Lamprologini ca

Structural coloration in a fossil feather.

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Vinther, Jakob; Briggs, Derek E G; Clarke, Julia; Mayr, Gerald; Prum, Richard O

2010-02-23

Investigation of feathers from the famous Middle Eocene Messel Oil Shale near Darmstadt, Germany shows that they are preserved as arrays of fossilized melanosomes, the surrounding beta-keratin having degraded. The majority of feathers are preserved as aligned rod-shaped eumelanosomes. In some, however, the barbules of the open pennaceous, distal portion of the feather vane are preserved as a continuous external layer of closely packed melanosomes enclosing loosely aligned melanosomes. This arrangement is similar to the single thin-film nanostructure that generates an iridescent, structurally coloured sheen on the surface of black feathers in many lineages of living birds. This is, to our knowledge, the first evidence of preservation of a colour-producing nanostructure in a fossil feather and confirms the potential for determining colour differences in ancient birds and other dinosaurs.

Fossil evidence of the zygomycetous fungi

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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

Variation in osteocytes morphology vs bone type in turtle shell and their exceptional preservation from the Jurassic to the present.

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Cadena, Edwin A; Schweitzer, Mary H

2012-09-01

Here we describe variations in osteocytes derived from each of the three bone layers that comprise the turtle shell. We examine osteocytes in bone from four extant turtle species to form a morphological 'baseline', and then compare these with morphologies of osteocytes preserved in Cenozoic and Mesozoic fossils. Two different morphotypes of osteocytes are recognized: flattened-oblate osteocytes (FO osteocytes), which are particularly abundant in the internal cortex and lamellae of secondary osteons in cancellous bone, and stellate osteocytes (SO osteocytes), principally present in the interstitial lamellae between secondary osteons and external cortex. We show that the morphology of osteocytes in each of the three bone layers is conserved through ontogeny. We also demonstrate that these morphological variations are phylogenetically independent, as well as independent of the bone origin (intramembranous or endochondral). Preservation of microstructures consistent with osteocytes in the morphology in Cenozoic and Mesozoic fossil turtle bones appears to be common, and occurs in diverse diagenetic environments including marine, freshwater, and terrestrial deposits. These data have potential to illuminate aspects of turtle biology and evolution previously unapproachable, such as estimates of genome size of extinct species, differences in metabolic rates among different bones from a single individual, and potential function of osteocytes as capsules for preservation of ancient biomolecules. Copyright © 2012 Elsevier Inc. All rights reserved.

Soft tissue preservation in a fossil marine lizard with a bilobed tail fin.

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Lindgren, Johan; Kaddumi, Hani F; Polcyn, Michael J

2013-01-01

Mosasaurs are secondarily aquatic squamates that became the dominant marine reptiles in the Late Cretaceous about 98-66 million years ago. Although early members of the group possessed body shapes similar to extant monitor lizards, derived forms have traditionally been portrayed as long, sleek animals with broadened, yet ultimately tapering tails. Here we report an extraordinary mosasaur fossil from the Maastrichtian of Harrana in central Jordan, which preserves soft tissues, including high fidelity outlines of a caudal fluke and flippers. This specimen provides the first indisputable evidence that derived mosasaurs were propelled by hypocercal tail fins, a hypothesis that was previously based on comparative skeletal anatomy alone. Ecomorphological comparisons suggest that derived mosasaurs were similar to pelagic sharks in terms of swimming performance, a finding that significantly expands our understanding of the level of aquatic adaptation achieved by these seagoing lizards.

The Late Devonian Gogo Formation Lägerstatte of Western Australia: Exceptional Early Vertebrate Preservation and Diversity

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Long, John A.; Trinajstic, Kate

2010-05-01

The Gogo Formation of Western Australia preserves a unique Late Devonian (Frasnian) reef fauna. The exceptional three-dimensional preservation of macrofossils combined with unprecedented soft-tissue preservation (including muscle bundles, nerve cells, and umbilical structures) has yielded a particularly rich assemblage with almost 50 species of fishes described. The most significant discoveries have contributed to resolving placoderm phylogeny and elucidating their reproductive physiology. Specifically, these discoveries have produced data on the oldest known vertebrate embryos; the anatomy of the primitive actinopterygian neurocranium and phylogeny of the earliest actinopterygians; the histology, radiation, and plasticity of dipnoan (lungfish) dental and cranial structures; the anatomy and functional morphology of the extinct onychodonts; and the anatomy of the primitive tetrapodomorph head and pectoral fin.

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

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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.

3D microstructural architecture of muscle attachments in extant and fossil vertebrates revealed by synchrotron microtomography.

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Sophie Sanchez

Full Text Available BACKGROUND: Firm attachments binding muscles to skeleton are crucial mechanical components of the vertebrate body. These attachments (entheses are complex three-dimensional structures, containing distinctive arrangements of cells and fibre systems embedded in the bone, which can be modified during ontogeny. Until recently it has only been possible to obtain 2D surface and thin section images of entheses, leaving their 3D histology largely unstudied except by extrapolation from 2D data. Entheses are frequently preserved in fossil bones, but sectioning is inappropriate for rare or unique fossil material. METHODOLOGY/PRINCIPAL FINDINGS: Here we present the first non-destructive 3D investigation, by propagation phase contrast synchrotron microtomography (PPC-SRµCT, of enthesis histology in extant and fossil vertebrates. We are able to identify entheses in the humerus of the salamander Desmognathus from the organization of bone-cell lacunae and extrinsic fibres. Statistical analysis of the lacunae differentiates types of attachments, and the orientation of the fibres, reflect the approximate alignment of the muscle. Similar histological structures, including ontogenetically related pattern changes, are perfectly preserved in two 380 million year old fossil vertebrates, the placoderm Compagopiscis croucheri and the sarcopterygian fish Eusthenopteron foordi. CONCLUSIONS/SIGNIFICANCE: We are able to determine the position of entheses in fossil vertebrates, the approximate orientation of the attached muscles, and aspects of their ontogenetic histories, from PPC-SRµCT data. Sub-micron microtomography thus provides a powerful tool for studying the structure, development, evolution and palaeobiology of muscle attachments.

An extraordinary gobioid fish fossil from Southern France.

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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.

The Quality of the Fossil Record: Populations, Species, and Communities

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Kidwell, Susan M.; Flessa, Karl W.

Paleontologists have always been concerned about the documentary quality of the fossil record, and this has also become an important issue for biologists, who increasingly look to accumulations of bones, shells, and plant material as possible ways to extend the time-frame of observation on species and community behaviors. Quantitative data on the postmortem behavior of organic remains in modern environments are providing new insights into death and fossil assemblages as sources of biological information. Important findings include: 1. With the exception of a few circumstances, usually recognizable by independent criteria, transport out of the original life habitat affects few individuals. 2. Most species with preservable hard-parts are in fact represented in the local death assemblage, commonly in correct rank importance. Molluscs are the most durable of modern aquatic groups studied so far, and they show highest fidelity to the original community. 3. Time-averaging of remains from successive generations and communities often prevents the detection of short term (seasons, years) variability but provides an excellent record of the natural range of community composition and structure over longer periods. Thus, although a complex array of processes and circumstances influences preservation, death assemblages of resistant skeletal elements are for many major groups good to excellent records of community composition, morphological variation, and environmental and geographic distribution of species, and such assemblages can record dynamics at ecologically and evolutionarily meaningful scales.

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

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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.

Do fossil vertebrate biominerals hold the key to the Palaeozoic climate?

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Žigaitė, Ž.

2012-04-01

Fossil vertebrate hard tissues - teeth and dermoskeleton - are considered among the most geochemically stable biominerals, and therefore are widely used for palaeoenvironmental and palaeoclimatic reconstructions. Elemental and isotopic compositions of fossil dental tissues may provide unique palaeoenvironmental information, ranging from the diet and trophic positions on a food chain, to the palaeosalinity and water temperatures of ancient seas. However, the post-mortem alteration and re-crystallisation of fossil hard tissues may hamper these interpretations. Chemical composition and isotopic equilibrium of the biomineral change readily at any time from the earliest diagenesis to the final laboratory acid treatment during the fossil preparation. This is why particular attention shall be given to the preservation of fossil tissues, evaluating carefully the level of possible alteration in the primary geochemical composition. Pre-evaluation of fossil preservation can be made by semi-quantitative spot geochemistry analyses on fine polished teeth and scale thin sections using Energy Dispersive X-ray Spectroscopy (EDS), and help to preview the chemical composition of biomineral. The Electron Backscatter Diffractometry (EBSD) is useful to examine the cristallinity and possible structural alterations. In addition, rare earth element (REE) abundances can be measured in situ within the fine fossil tissues (such as enamel) using Laser Ablation Inductively Coupled Plasma Mass-spectrometry (LA-ICP-MS), giving evidence on the selective geochemical resilience between separate vertebrate hard tissues. Therefore, in order to decipher the geochemical signal correctly, the evaluation of preservation is a necessary starting point to any further studies of fossil biomineral geochemistry.

Macro fossils vegetable in Palmar formation (later pleistocene) in Entre Rios - Argentina

International Nuclear Information System (INIS)

Ramos, R.; Brea, M.; Krohling, D.

2012-01-01

This work is about the macro fossil knowledge preserved like wood fossils in the El Palmar Formation (Late Pleistocene) from a systematic - anatomical as well as paleoecological and paleoclimate point of view.The paleo Flora comes from various fossil located in the province of Entre Rios - Argentina

Compression map, functional groups and fossilization: A chemometric approach (Pennsylvanian neuropteroid foliage, Canada)

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D'Angelo, J. A.; Zodrow, E.L.; Mastalerz, Maria

2012-01-01

Nearly all of the spectrochemical studies involving Carboniferous foliage of seed-ferns are based on a limited number of pinnules, mainly compressions. In contrast, in this paper we illustrate working with a larger pinnate segment, i.e., a 22-cm long neuropteroid specimen, compression-preserved with cuticle, the compression map. The objective is to study preservation variability on a larger scale, where observation of transparency/opacity of constituent pinnules is used as a first approximation for assessing the degree of pinnule coalification/fossilization. Spectrochemical methods by Fourier transform infrared spectrometry furnish semi-quantitative data for principal component analysis.The compression map shows a high degree of preservation variability, which ranges from comparatively more coalified pinnules to less coalified pinnules that resemble fossilized-cuticles, noting that the pinnule midveins are preserved more like fossilized-cuticles. A general overall trend of coalified pinnules towards fossilized-cuticles, i.e., variable chemistry, is inferred from the semi-quantitative FTIR data as higher contents of aromatic compounds occur in the visually more opaque upper location of the compression map. The latter also shows a higher condensation of the aromatic nuclei along with some variation in both ring size and degree of aromatic substitution. From principal component analysis we infer correspondence between transparency/opacity observation and chemical information which correlate with varying degree to fossilization/coalification among pinnules. ?? 2011 Elsevier B.V.

The isotopic biosignatures of photo- vs. thiotrophic bivalves: are they preserved in fossil shells?

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Dreier, A; Loh, W; Blumenberg, M; Thiel, V; Hause-Reitner, D; Hoppert, M

2014-09-01

Symbiont-bearing and non-symbiotic marine bivalves were used as model organisms to establish biosignatures for the detection of distinctive symbioses in ancient bivalves. For this purpose, the isotopic composition of lipids (δ13C) and bulk organic shell matrix (δ13C, δ34S, δ15N) from shells of several thiotrophic, phototrophic, or non-symbiotic bivalves were compared (phototrophic: Fragum fragum, Fragum unedo, Tridacna maxima; thiotrophic: Codakia tigerina, Fimbria fimbriata, Anodontia sp.; non-symbiotic: Tapes dorsatus, Vasticardium vertebratum, Scutarcopagia sp.). ∆13C values of bulk organic shell matrices, most likely representing mainly original shell protein/chitin biomass, were depleted in thio- and phototrophic bivalves compared to non-symbiotic bivalves. As the bulk organic shell matrix also showed a major depletion of δ15N (down to -2.2 ‰) for thiotrophic bivalves, combined δ13C and δ15N values are useful to differentiate between thio-, phototrophic, and non-symbiotic lifestyles. However, the use of these isotopic signatures for the study of ancient bivalves is limited by the preservation of the bulk organic shell matrix in fossils. Substantial alteration was clearly shown by detailed microscopic analyses of fossil (late Pleistocene) T. maxima and Trachycardium lacunosum shell, demonstrating a severe loss of quantity and quality of bulk organic shell matrix with time. Likewise, the composition and δ13C-values of lipids from empty shells indicated that a large part of these compounds derived from prokaryotic decomposers. The use of lipids from ancient shells for the reconstruction of the bivalve's life style therefore appears to be restricted. © 2014 John Wiley & Sons Ltd.

A fossil protein chimera; difficulties in discriminating dinosaur peptide sequences from modern cross-contamination

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Warwood, Stacey; van Dongen, Bart; Kitchener, Andrew C.; Manning, Phillip L.

2017-01-01

A decade ago, reports that organic-rich soft tissue survived from dinosaur fossils were apparently supported by proteomics-derived sequence information of exceptionally well-preserved bone. This initial claim to the sequencing of endogenous collagen peptides from an approximately 68 Myr Tyrannosaurus rex fossil was highly controversial, largely on the grounds of potential contamination from either bacterial biofilms or from laboratory practice. In a subsequent study, collagen peptide sequences from an approximately 78 Myr Brachylophosaurus canadensis fossil were reported that have remained largely unchallenged. However, the endogeneity of these sequences relies heavily on a single peptide sequence, apparently unique to both dinosaurs. Given the potential for cross-contamination from modern bone analysed by the same team, here we extract collagen from bone samples of three individuals of ostrich, Struthio camelus. The resulting LC–MS/MS data were found to match all of the proposed sequences for both the original Tyrannosaurus and Brachylophosaurus studies. Regardless of the true nature of the dinosaur peptides, our finding highlights the difficulty of differentiating such sequences with confidence. Our results not only imply that cross-contamination cannot be ruled out, but that appropriate measures to test for endogeneity should be further evaluated. PMID:28566488

Features of deep cave sediments: their influence on fossil preservation

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Cobo, R.

2003-08-01

Full Text Available We analyse how physical and chemical deep-cave sediment features preserve the morphological and geochemical characteristics of paleontological materials. Detrital sediment chemistry and clast size are fundamental because they provide a soft, impervious and plastic environment in which fossil remains are transported with minimal erosion. Sediment mineralogy provides a carbonate- and phosphate-buffered environment in which molecules of biological origin hydrolyze slower than in open-air environments or even at cave entrance sites. Because permafrost did not develop in the Iberian Peninsula (at least at the altitudes of inhabited caves, sediment desiccation never took place. In addition, sediment -pores were not aerated, which protected fossil remains from air (oxygen-linked weathering. The annual-temperature variation inside sediment was negligible, which contributed to amino acid racemization dating. Collagen amino acid and amino acid racemization analysis of cave bear and man samples from cave sediments dated from different Oxygen Isotope Stages (4": Sidrón, Amutxate, Troskaeta, El Toll, Coro Tracito, Ekain, Lezetxiki, La Pasada, Eirós; 5": Reguerillo and Arrikrutz; 6"-7": Sima de los Huesos demonstrate that important amounts of almost intact collagen still remain in teeth dentine. Fossil DNA search seems to be very promising.En este trabajo se analiza el papel que juegan las características físicas y químicas de los sedimentos de galerías profundas de cuevas en la preservación de los caracteres morfológicos y paleobiomoleculares del material paleontológico incluido en dichos sedimentos. Los aspectos geoquímicos y de tamaño de grano del sedimento son críticos: las características generan un medio blando, plástico e impermeable que permite el transporte -mecánico sin grave deterioro del material (en coladas de barro; las características químicas mineralogía del sediment* proporcionan un ambiente con tampón fosfatado

Convergent evolution in aquatic tetrapods: insights from an exceptional fossil mosasaur.

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Johan Lindgren

Full Text Available Mosasaurs (family Mosasauridae are a diverse group of secondarily aquatic lizards that radiated into marine environments during the Late Cretaceous (98-65 million years ago. For the most part, they have been considered to be simple anguilliform swimmers--i.e., their propulsive force was generated by means of lateral undulations incorporating the greater part of the body--with unremarkable, dorsoventrally narrow tails and long, lizard-like bodies. Convergence with the specialized fusiform body shape and inferred carangiform locomotory style (in which only a portion of the posterior body participates in the thrust-producing flexure of ichthyosaurs and metriorhynchid crocodyliform reptiles, along with cetaceans, has so far only been recognized in Plotosaurus, the most highly derived member of the Mosasauridae. Here we report on an exceptionally complete specimen (LACM 128319 of the moderately derived genus Platecarpus that preserves soft tissues and anatomical details (e.g., large portions of integument, a partial body outline, putative skin color markings, a downturned tail, branching bronchial tubes, and probable visceral traces to an extent that has never been seen previously in any mosasaur. Our study demonstrates that a streamlined body plan and crescent-shaped caudal fin were already well established in Platecarpus, a taxon that preceded Plotosaurus by 20 million years. These new data expand our understanding of convergent evolution among marine reptiles, and provide insights into their evolution's tempo and mode.

First direct evidence of a vertebrate three-level trophic chain in the fossil record.

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Kriwet, Jürgen; Witzmann, Florian; Klug, Stefanie; Heidtke, Ulrich H J

2008-01-22

We describe the first known occurrence of a Permian shark specimen preserving two temnospondyl amphibians in its digestive tract as well as the remains of an acanthodian fish, which was ingested by one of the temnospondyls. This exceptional find provides for the first time direct evidence of a vertebrate three-level food chain in the fossil record with the simultaneous preservation of three trophic levels. Our analysis shows that small-sized Lower Permian xenacanthid sharks of the genus Triodus preyed on larval piscivorous amphibians. The recorded trophic interaction can be explained by the adaptation of certain xenacanthids to fully freshwater environments and the fact that in these same environments, large temnospondyls occupied the niche of modern crocodiles. This unique faunal association has not been documented after the Permian and Triassic. Therefore, this Palaeozoic three-level food chain provides strong and independent support for changes in aquatic trophic chain structures through time.

Otoliths as an integral part in fossil fish taxonomy

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Christoph Gierl

2015-11-01

Full Text Available Otoliths are small structures in the skull of fishes. They are responsible for hearing and orientation in the 3-dimensional space. They also hold valuable information regarding the taxonomy. Their outline, the shape of the sulcus and other features allow the determination of a fish even to the species level. A lot of fossil species are solely based on otoliths because of their good chance of preservation. Gobies are in this case no different. An additional challenge in gobies is their high similarity between species concerning the preservable parts. Fossil skeletons that are 20 Million years old can show only few differences compared to recent gobies. These features are often hardly recognizable due to their preservation. As a consequence many fossil gobies have been assigned to the genus Gobius sensu lato. Examples are two gobies from the Miocene of Southern Germany. They have a unique combination of characters (six branchiostegals, palatine resembling a “T”, no entopterygoid that allows the rectification of a new fossil genus but the two species are hardly distinguishable based only on the skeleton. The key hints in having two species are the otoliths. They show slight but consistent differences in their outline. This shows that otoliths can be a key feature in species identification. They should also be taken into consideration by recent fish species. Not to mention their possible phylogenetic potential that remains to be explored.

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

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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.

Natural product terpenoids in Eocene and Miocene conifer fossils.

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

2002-08-30

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

Oxygen and Hydrogen Stable Isotope Composition of Eocene ( ~45 million year old) Fossil Tree Cellulose

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Jahren, H.

2001-05-01

I report on \\delta18O and \\deltaD values gained from unusually old tree fossils, collected on Axel Heiberg Island of the Canadian High Arctic. A variety of workers have measured the δ ^{18}O value of cellulose and the δ D value of cellulose nitrate isolated from modern trees and compared it to various environmental parameters (esp. Epstein et al., 1977: 14 tree species sampled at 16 sites ranging from 18 \\deg to 62 \\deg North latitude; \\delta18O of cellulose ranged from +20 to +33 \\permil; \\deltaD of cellulose nitrate ranged from -181 to +18). To date the paleoenvironmental interpretations resulting from these studies have been restricted to application in recent and Quaternary earth history due to the lack of sufficiently preserved cellulose and tree ring structure in older tree fossils. An exception to this generalization are the middle Eocene (\\sim45 my old) fossil forests of Axel Heiberg Island, which contain abundant stumps, branches, twigs, cones and leaves of Metasequoia trees in exquisite preservational condition. These deciduous trees grew at a paleolatitude of 80 ° North, and endured prolonged periods of continuous daylight in the summer and continuous darkness in the winter, making the ecosystem completely unlike any forest community existing today. Fossil wood samples from the site have been slightly compressed, but otherwise exhibit minimal alteration: %C and % cellulose (by mass) are similar to modern Metasequoia wood. δ ^{18}O analyses on cellulose isolated from 14 fossil individuals has yielded the following results: range = +17 to +20 ‰ ; mean = +19 ‰ ; variability within an individual = 0.5 to 1.0 ‰ . In presentation, I will complement these results with δ D determinations on cellulose nitrate isolated from the same individuals, as well as from small plants presently growing in the arctic. I will also discuss the surprising result that Axel Heiberg fossil trees appear to have stable isotope composition as low or lower than trees

The fossil record and taphonomy of butterflies and moths (Insecta, Lepidoptera): implications for evolutionary diversity and divergence-time estimates.

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Sohn, Jae-Cheon; Labandeira, Conrad C; Davis, Donald R

2015-02-04

It is conventionally accepted that the lepidopteran fossil record is significantly incomplete when compared to the fossil records of other, very diverse, extant insect orders. Such an assumption, however, has been based on cumulative diversity data rather than using alternative statistical approaches from actual specimen counts. We reviewed documented specimens of the lepidopteran fossil record, currently consisting of 4,593 known specimens that are comprised of 4,262 body fossils and 331 trace fossils. The temporal distribution of the lepidopteran fossil record shows significant bias towards the late Paleocene to middle Eocene time interval. Lepidopteran fossils also record major shifts in preservational style and number of represented localities at the Mesozoic stage and Cenozoic epoch level of temporal resolution. Only 985 of the total known fossil specimens (21.4%) were assigned to 23 of the 40 extant lepidopteran superfamilies. Absolute numbers and proportions of preservation types for identified fossils varied significantly across superfamilies. The secular increase of lepidopteran family-level diversity through geologic time significantly deviates from the general pattern of other hyperdiverse, ordinal-level lineages. Our statistical analyses of the lepidopteran fossil record show extreme biases in preservation type, age, and taxonomic composition. We highlight the scarcity of identified lepidopteran fossils and provide a correspondence between the latest lepidopteran divergence-time estimates and relevant fossil occurrences at the superfamily level. These findings provide caution in interpreting the lepidopteran fossil record through the modeling of evolutionary diversification and in determination of divergence time estimates.

A fossil protein chimera; difficulties in discriminating dinosaur peptide sequences from modern cross-contamination.

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Buckley, Michael; Warwood, Stacey; van Dongen, Bart; Kitchener, Andrew C; Manning, Phillip L

2017-05-31

A decade ago, reports that organic-rich soft tissue survived from dinosaur fossils were apparently supported by proteomics-derived sequence information of exceptionally well-preserved bone. This initial claim to the sequencing of endogenous collagen peptides from an approximately 68 Myr Tyrannosaurus rex fossil was highly controversial, largely on the grounds of potential contamination from either bacterial biofilms or from laboratory practice. In a subsequent study, collagen peptide sequences from an approximately 78 Myr Brachylophosaurus canadensis fossil were reported that have remained largely unchallenged. However, the endogeneity of these sequences relies heavily on a single peptide sequence, apparently unique to both dinosaurs. Given the potential for cross-contamination from modern bone analysed by the same team, here we extract collagen from bone samples of three individuals of ostrich, Struthio camelus The resulting LC-MS/MS data were found to match all of the proposed sequences for both the original Tyrannosaurus and Brachylophosaurus studies. Regardless of the true nature of the dinosaur peptides, our finding highlights the difficulty of differentiating such sequences with confidence. Our results not only imply that cross-contamination cannot be ruled out, but that appropriate measures to test for endogeneity should be further evaluated. © 2017 The Authors.

Exceptional preservation of children's footprints from a Holocene footprint site in Namibia

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Bennett, Matthew R.; Morse, Sarita A.; Liutkus-Pierce, Cynthia; McClymont, Juliet; Evans, Mary; Crompton, Robin H.; Francis Thackeray, J.

2014-09-01

Here we report on a Holocene inter-dune site close to Walvis Bay (Namibia) which contains exceptionally well-preserved children's footprints. The footprint surface is dated using Optically Stimulated Luminescence (OSL) methods to approximately 1.5 ka. These dates are compared to those obtained at nearby footprint sites and used to verify a model of diachronous footprint surfaces and also add to the archaeological data available for the communities that occupied these near-coastal areas during the Holocene. This model of diachronous footprint surfaces has implications for other soft-sediment footprint sites such as the 1.5 Ma old footprints at Ileret (Kenya). The distribution of both human and animal tracks, is consistent with the passage of small flock of small ungulates (probably sheep/goats) followed by a group of approximately 9 ± 2 individuals (children or young adults). Age estimates from the tracks suggest that some of the individuals may have been as young as five years old. Variation in track topology across this sedimentologically uniform surface is explained in terms of variations in gait and weight/stature of the individual print makers and is used to corroborate a model of footprint morphology developed at a nearby site. The significance of the site within the literature on human footprints lies in the quality of the track preservation, their topological variability despite a potentially uniform substrate, and the small size of the tracks, and therefore the inferred young age of the track-makers. The site provides an emotive insight into the life of the track-makers.

The first fossil cyphophthalmid harvestman from Baltic amber

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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.

Preservation of the bone protein osteocalcin in dinosaurs

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Muyzer, Gerard; Sandberg, Philip; Knapen, Marjo H. J.; Vermeer, Cees; Collins, Matthew; Westbroek, Peter

1992-10-01

Two different immunological assays were used to identify the remains of a bone matrix protein, osteocalcin (OC), in the bones of dinosaurs and other fossil vertebrates. Antibodies raised against OC from modern vertebrates showed strong immunological cross-reactivity with modern and relatively young fossil samples and significant reactions with some of the dinosaur bone extracts. The presence of OC was confirmed by the detection of a peptide-bound, uniquely vertebrate amino acid, γcarboxyglutamic acid (Gla). Preservation of OC in fossil bones appears to be strongly dependent on the burial history and not simply on age. These results extend the range of protein preservation in the geologic record and provide a first step toward a molecular phylogeny of the dinosaurs.

A fossil brain from the Cretaceous of European Russia and avian sensory evolution.

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Kurochkin, Evgeny N; Dyke, Gareth J; Saveliev, Sergei V; Pervushov, Evgeny M; Popov, Evgeny V

2007-06-22

Fossils preserving traces of soft anatomy are rare in the fossil record; even rarer is evidence bearing on the size and shape of sense organs that provide us with insights into mode of life. Here, we describe unique fossil preservation of an avian brain from the Volgograd region of European Russia. The brain of this Melovatka bird is similar in shape and morphology to those of known fossil ornithurines (the lineage that includes living birds), such as the marine diving birds Hesperornis and Enaliornis, but documents a new stage in avian sensory evolution: acute nocturnal vision coupled with well-developed hearing and smell, developed by the Late Cretaceous (ca 90Myr ago). This fossil also provides insights into previous 'bird-like' brain reconstructions for the most basal avian Archaeopteryx--reduction of olfactory lobes (sense of smell) and enlargement of the hindbrain (cerebellum) occurred subsequent to Archaeopteryx in avian evolution, closer to the ornithurine lineage that comprises living birds. The Melovatka bird also suggests that brain enlargement in early avians was not correlated with the evolution of powered flight.

Mineralogy of Non-Silicified Fossil Wood

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George E. Mustoe

2018-03-01

Full Text Available The best-known and most-studied petrified wood specimens are those that are mineralized with polymorphs of silica: opal-A, opal-C, chalcedony, and quartz. Less familiar are fossil woods preserved with non-silica minerals. This report reviews discoveries of woods mineralized with calcium carbonate, calcium phosphate, various iron and copper minerals, manganese oxide, fluorite, barite, natrolite, and smectite clay. Regardless of composition, the processes of mineralization involve the same factors: availability of dissolved elements, pH, Eh, and burial temperature. Permeability of the wood and anatomical features also plays important roles in determining mineralization. When precipitation occurs in several episodes, fossil wood may have complex mineralogy.

The fossil record of the sixth extinction.

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Plotnick, Roy E; Smith, Felisa A; Lyons, S Kathleen

2016-05-01

Comparing the magnitude of the current biodiversity crisis with those in the fossil record is difficult without an understanding of differential preservation. Integrating data from palaeontological databases with information on IUCN status, ecology and life history characteristics of contemporary mammals, we demonstrate that only a small and biased fraction of threatened species (fossil record, compared with 20% of non-threatened species. We find strong taphonomic biases related to body size and geographic range. Modern species with a fossil record tend to be large and widespread and were described in the 19(th) century. The expected magnitude of the current extinction based only on species with a fossil record is about half of that of one based on all modern species; values for genera are similar. The record of ancient extinctions may be similarly biased, with many species having originated and gone extinct without leaving a tangible record. © 2016 John Wiley & Sons Ltd/CNRS.

Fossilization Processes in Thermal Springs

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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

A new ankylosaurine dinosaur from the Judith River Formation of Montana, USA, based on an exceptional skeleton with soft tissue preservation

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Arbour, Victoria M.; Evans, David C.

2017-05-01

The terrestrial Judith River Formation of northern Montana was deposited over an approximately 4 Myr interval during the Campanian (Late Cretaceous). Despite having been prospected and collected continuously by palaeontologists for over a century, few relatively complete dinosaur skeletons have been recovered from this unit to date. Here we describe a new genus and species of ankylosaurine dinosaur, Zuul crurivastator, from the Coal Ridge Member of the Judith River Formation, based on an exceptionally complete and well-preserved skeleton (ROM 75860). This is the first ankylosaurin skeleton known with a complete skull and tail club, and it is the most complete ankylosaurid ever found in North America. The presence of abundant soft tissue preservation across the skeleton, including in situ osteoderms, skin impressions and dark films that probably represent preserved keratin, make this exceptional skeleton an important reference for understanding the evolution of dermal and epidermal structures in this clade. Phylogenetic analysis recovers Zuul as an ankylosaurin ankylosaurid within a clade of Dyoplosaurus and Scolosaurus, with Euoplocephalus being more distantly related within Ankylosaurini. The occurrence of Z. crurivastator from the upper Judith River Formation fills a gap in the ankylosaurine stratigraphic and geographical record in North America, and further highlights that Campanian ankylosaurines were undergoing rapid evolution and stratigraphic succession of taxa as observed for Laramidian ceratopsids, hadrosaurids, pachycephalosaurids and tyrannosaurids.

New insights into Mesozoic cycad evolution: an exploration of anatomically preserved Cycadaceae seeds from the Jurassic Oxford Clay biota

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Alan R.T. Spencer

2017-08-01

Full Text Available Most knowledge concerning Mesozoic Era floras has come from compression fossils. This has been augmented in the last 20 years by rarer permineralized material showing cellular preservation. Here, we describe a new genus of anatomically preserved gymnosperm seed from the Callovian–Oxfordian (Jurassic Oxford Clay Formation (UK, using a combination of traditional sectioning and synchrotron radiation X-ray micro-tomography (SRXMT. Oxfordiana motturii gen. et sp. nov. is large and bilaterally symmetrical. It has prominent external ribs, and has a three-layered integument comprising: a narrow outer layer of thick walled cells; a thick middle parenchymatous layer; and innermost a thin fleshy layer. The integument has a longitudinal interior groove and micropyle, enveloping a nucellus with a small pollen chamber. The large size, bilateral symmetry and integumentary groove demonstrate an affinity for the new species within the cycads. Moreover, the internal groove in extant taxa is an autapomorphy of the genus Cycas, where it facilitates seed germination. Based upon the unique seed germination mechanism shared with living species of the Cycadaceae, we conclude that O. motturii is a member of the stem-group lineage leading to Cycas after the Jurassic divergence of the Cycadaceae from other extant cycads. SRXMT—for the first time successfully applied to fossils already prepared as slides—reveals the distribution of different mineral phases within the fossil, and allows us to evaluate the taphonomy of Oxfordiana. An early pyrite phase replicates the external surfaces of individual cells, a later carbonate component infilling void spaces. The resulting taphonomic model suggests that the relatively small size of the fossils was key to their exceptional preservation, concentrating sulfate-reducing bacteria in a locally closed microenvironment and thus facilitating soft-tissue permineralization.

Estimating Age-Dependent Extinction: Contrasting Evidence from Fossils and Phylogenies.

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Hagen, Oskar; Andermann, Tobias; Quental, Tiago B; Antonelli, Alexandre; Silvestro, Daniele

2018-05-01

The estimation of diversification rates is one of the most vividly debated topics in modern systematics, with considerable controversy surrounding the power of phylogenetic and fossil-based approaches in estimating extinction. Van Valen's seminal work from 1973 proposed the "Law of constant extinction," which states that the probability of extinction of taxa is not dependent on their age. This assumption of age-independent extinction has prevailed for decades with its assessment based on survivorship curves, which, however, do not directly account for the incompleteness of the fossil record, and have rarely been applied at the species level. Here, we present a Bayesian framework to estimate extinction rates from the fossil record accounting for age-dependent extinction (ADE). Our approach, unlike previous implementations, explicitly models unobserved species and accounts for the effects of fossil preservation on the observed longevity of sampled lineages. We assess the performance and robustness of our method through extensive simulations and apply it to a fossil data set of terrestrial Carnivora spanning the past 40 myr. We find strong evidence of ADE, as we detect the extinction rate to be highest in young species and declining with increasing species age. For comparison, we apply a recently developed analogous ADE model to a dated phylogeny of extant Carnivora. Although the phylogeny-based analysis also infers ADE, it indicates that the extinction rate, instead, increases with increasing taxon age. The estimated mean species longevity also differs substantially, with the fossil-based analyses estimating 2.0 myr, in contrast to 9.8 myr derived from the phylogeny-based inference. Scrutinizing these discrepancies, we find that both fossil and phylogeny-based ADE models are prone to high error rates when speciation and extinction rates increase or decrease through time. However, analyses of simulated and empirical data show that fossil-based inferences are more

Taphonomy of the fossil insects of the middle Eocene Kishenehn Formation

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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.

Electron Microscopy and Analytical X-ray Characterization of Compositional and Nanoscale Structural Changes in Fossil Bone

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Boatman, Elizabeth Marie

The nanoscale structure of compact bone contains several features that are direct indicators of bulk tissue mechanical properties. Fossil bone tissues represent unique opportunities to understand the compact bone structure/property relationships from a deep time perspective, offering a possible array of new insights into bone diseases, biomimicry of composite materials, and basic knowledge of bioapatite composition and nanoscale bone structure. To date, most work with fossil bone has employed microscale techniques and has counter-indicated the survival of bioapatite and other nanoscale structural features. The obvious disconnect between the use of microscale techniques and the discernment of nanoscale structure has prompted this work. The goal of this study was to characterize the nanoscale constituents of fossil compact bone by applying a suite of diffraction, microscopy, and spectrometry techniques, representing the highest levels of spatial and energy resolution available today, and capable of complementary structural and compositional characterization from the micro- to the nanoscale. Fossil dinosaur and crocodile long bone specimens, as well as modern ratite and crocodile femurs, were acquired from the UC Museum of Paleontology. Preserved physiological features of significance were documented with scanning electron microscopy back-scattered imaging. Electron microprobe wavelength-dispersive X-ray spectroscopy (WDS) revealed fossil bone compositions enriched in fluorine with a complementary loss of oxygen. X-ray diffraction analyses demonstrated that all specimens were composed of apatite. Transmission electron microscopy (TEM) imaging revealed preserved nanocrystallinity in the fossil bones and electron diffraction studies further identified these nanocrystallites as apatite. Tomographic analyses of nanoscale elements imaged by TEM and small angle X-ray scattering were performed, with the results of each analysis further indicating that nanoscale structure is

Caught in the act: the first record of copulating fossil vertebrates.

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Joyce, Walter G; Micklich, Norbert; Schaal, Stephan F K; Scheyer, Torsten M

2012-10-23

The behaviour of fossil organisms can typically be inferred only indirectly, but rare fossil finds can provide surprising insights. Here, we report from the Eocene Messel Pit Fossil Site between Darmstadt and Frankfurt, Germany numerous pairs of the fossil carettochelyid turtle Allaeochelys crassesculpta that represent for the first time among fossil vertebrates couples that perished during copulation. Females of this taxon can be distinguished from males by their relatively shorter tails and development of plastral kinesis. The preservation of mating pairs has important taphonomic implications for the Messel Pit Fossil Site, as it is unlikely that the turtles would mate in poisonous surface waters. Instead, the turtles initiated copulation in habitable surface waters, but perished when their skin absorbed poisons while sinking into toxic layers. The mating pairs from Messel are therefore more consistent with a stratified, volcanic maar lake with inhabitable surface waters and a deadly abyss.

Evaluation of early Archean volcaniclastic and volcanic flow rocks as possible sites for carbonaceous fossil microbes.

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Walsh, Maud M

2004-01-01

Sedimentary rocks have traditionally been the focus of the search for Archean microfossils; the Earth's oldest fossil bacteria are associated with carbonaceous matter in sedimentary cherts in greenstone belts in the eastern Pilbara block of Western Australia and Barberton greenstone belt of South Africa. Reports of possible fossils in a martian meteorite composed of igneous rock and the discovery of modern bacteria associated with basalts have stimulated a new look at Archean volcanic rocks as possible sites for fossil microbes. This study examines silicified volcaniclastic rocks, near-surface altered volcanic flow rocks, and associated stromatolite- like structures from the Archean Barberton greenstone belt to evaluate their potential for the preservation of carbonaceous fossils. Detrital carbonaceous particles are widely admixed with current-deposited debris. Carbonaceous matter is also present in altered volcanic flow rocks as sparse particles in silica veins that appear to be fed by overlying carbonaceous chert layers. Neither microfossils nor mat-like material was identified in the altered volcanic rocks or adjacent stromatolite-like structures. Ancient volcanic flow and volcaniclastic rocks are not promising sites for carbonaceous fossil preservation.

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

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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.

A new interpretation of the bee fossil Melitta willardi Cockerell (Hymenoptera, Melittidae) based on geometric morphometrics of the wing

OpenAIRE

Dewulf,Alexandre; De Meulemeester,Thibaut; Dehon,Manuel; Engel,Michael; Michez,Denis

2014-01-01

Abstract Although bees are one of the major lineages of pollinators and are today quite diverse, few well-preserved fossils are available from which to establish the tempo of their diversification/extinction since the Early Cretaceous. Here we present a reassessment of the taxonomic affinities of Melitta willardi Cockerell 1909, preserved as a compression fossil from the Florissant shales of Colorado, USA. Based on geometric morphometric wing shape analyses M. willardi cannot be confidently a...

Paleovegetation reconstruction of fossil forests dominated by Metasequoia and Glyptostrobus from the late Pliocene Kobiwako Group, central Japan

OpenAIRE

CHIYOMI, YAMAKAWA; ARATA, MOMOHARA; TOMOO, NUNOTANI; MIDORI, MATSUMOTO; YASUYUKI, WATANO; Lake Biwa Museum; Graduate School of Horticulture, Chiba University; Lake Biwa Museum; Graduate School of Science, Chiba University; Graduate School of Science, Chiba University

2008-01-01

A late Pliocene (1.8-1.9 Ma) wetland fossil forest community that was dominated by Metasequoia and Glyptostrobus was reconstructed based on the species composition of the stumps and other plant macrofossil assemblages. The plant fossils were recovered from a fossil forest preserved in deposits of the Kobiwako Group that are exposed in the Echi River, Shiga Prefecture, central Japan. Fossil wood of Metasequoia and Glyptostrobus was distinguished based on anatomical characteristics. Apportionme...

Cryptic iridescence in a fossil weevil generated by single diamond photonic crystals.

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McNamara, Maria E; Saranathan, Vinod; Locatelli, Emma R; Noh, Heeso; Briggs, Derek E G; Orr, Patrick J; Cao, Hui

2014-11-06

Nature's most spectacular colours originate in integumentary tissue architectures that scatter light via nanoscale modulations of the refractive index. The most intricate biophotonic nanostructures are three-dimensional crystals with opal, single diamond or single gyroid lattices. Despite intense interest in their optical and structural properties, the evolution of such nanostructures is poorly understood, due in part to a lack of data from the fossil record. Here, we report preservation of single diamond (Fd-3m) three-dimensional photonic crystals in scales of a 735,000 year old specimen of the brown Nearctic weevil Hypera diversipunctata from Gold Run, Canada, and in extant conspecifics. The preserved red to green structural colours exhibit near-field brilliancy yet are inconspicuous from afar; they most likely had cryptic functions in substrate matching. The discovery of pristine fossil examples indicates that the fossil record is likely to yield further data on the evolution of three-dimensional photonic nanostructures and their biological functions. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Uranium content and U-Th dating of fossil bones and dental tissues from Lazaret cave

International Nuclear Information System (INIS)

Michel, V.; Falgueres, Ch.; Yokoyama, Y.

1997-01-01

Fossil bone and dental tissues from Lazaret cave and modern ones are here the subject of a comparative microscopical study. Porous tissues such as dentine and bone have retained their Haversian and Tomes canals respectively. However, cracked areas with calcite were detected, indicating a water percolation within porous tissues and an alteration of tissue in places. In addition, compact fossil enamel is particularly well preserved. These results are essential for U-Tb and ESR dating application. Uranium contents, U-Tb ages of two fossil mandibular tissues, two tibias and of six burnt fossil bones are presented and discussed. (authors)

Fossilized biophotonic nanostructures reveal the original colors of 47-million-year-old moths.

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McNamara, Maria E; Briggs, Derek E G; Orr, Patrick J; Wedmann, Sonja; Noh, Heeso; Cao, Hui

2011-11-01

Structural colors are generated by scattering of light by variations in tissue nanostructure. They are widespread among animals and have been studied most extensively in butterflies and moths (Lepidoptera), which exhibit the widest diversity of photonic nanostructures, resultant colors, and visual effects of any extant organism. The evolution of structural coloration in lepidopterans, however, is poorly understood. Existing hypotheses based on phylogenetic and/or structural data are controversial and do not incorporate data from fossils. Here we report the first example of structurally colored scales in fossil lepidopterans; specimens are from the 47-million-year-old Messel oil shale (Germany). The preserved colors are generated by a multilayer reflector comprised of a stack of perforated laminae in the scale lumen; differently colored scales differ in their ultrastructure. The original colors were altered during fossilization but are reconstructed based upon preserved ultrastructural detail. The dorsal surface of the forewings was a yellow-green color that probably served as a dual-purpose defensive signal, i.e. aposematic during feeding and cryptic at rest. This visual signal was enhanced by suppression of iridescence (change in hue with viewing angle) achieved via two separate optical mechanisms: extensive perforation, and concave distortion, of the multilayer reflector. The fossils provide the first evidence, to our knowledge, for the function of structural color in fossils and demonstrate the feasibility of reconstructing color in non-metallic lepidopteran fossils. Plastic scale developmental processes and complex optical mechanisms for interspecific signaling had clearly evolved in lepidopterans by the mid-Eocene.

Fossilized biophotonic nanostructures reveal the original colors of 47-million-year-old moths.

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Maria E McNamara

2011-11-01

Full Text Available Structural colors are generated by scattering of light by variations in tissue nanostructure. They are widespread among animals and have been studied most extensively in butterflies and moths (Lepidoptera, which exhibit the widest diversity of photonic nanostructures, resultant colors, and visual effects of any extant organism. The evolution of structural coloration in lepidopterans, however, is poorly understood. Existing hypotheses based on phylogenetic and/or structural data are controversial and do not incorporate data from fossils. Here we report the first example of structurally colored scales in fossil lepidopterans; specimens are from the 47-million-year-old Messel oil shale (Germany. The preserved colors are generated by a multilayer reflector comprised of a stack of perforated laminae in the scale lumen; differently colored scales differ in their ultrastructure. The original colors were altered during fossilization but are reconstructed based upon preserved ultrastructural detail. The dorsal surface of the forewings was a yellow-green color that probably served as a dual-purpose defensive signal, i.e. aposematic during feeding and cryptic at rest. This visual signal was enhanced by suppression of iridescence (change in hue with viewing angle achieved via two separate optical mechanisms: extensive perforation, and concave distortion, of the multilayer reflector. The fossils provide the first evidence, to our knowledge, for the function of structural color in fossils and demonstrate the feasibility of reconstructing color in non-metallic lepidopteran fossils. Plastic scale developmental processes and complex optical mechanisms for interspecific signaling had clearly evolved in lepidopterans by the mid-Eocene.

Chemical techniques to extract organic fractions from fossil bones for accurate 14C dating

International Nuclear Information System (INIS)

Minami, Masayo; Muto, Hiroo; Nakamura, Toshio

2004-01-01

We examined different concentrations of HCl, such as 0.4, 0.6, 0.8, 1.0 and 1.2 M, for decalcification of fossil bones and different times of 0.1 M NaOH treatment on collagens to determine the best conditions for purifying collagen through extraction of humic contaminants, and compared the alkali treatment method with the XAD-2 treatment method for several types of fossils. The yield of acid-insoluble bone fractions did not change over the range from 0.4 to 1.0 M HCl and decreased suddenly with 1.2 M HCl on decalcification, and the 14 C ages of the extracted gelatins from the five decalcified fractions were unchanged, suggesting that 14 C ages as those of the XAD-purified hydrolysates. The NaOH-treatment time should be less than several hours to avoid a loss of collagen. The fossil bones used are relatively well-preserved, but the alkali treatment could bring about a lot of loss of organic bone proteins for poorly-preserved bones. The XAD-2 treatment method is effective for accurate radiocarbon dating of fossil bones, if the XAD-2 resin is completely pre-cleaned

A Total-Evidence Approach to Dating with Fossils, Applied to the Early Radiation of the Hymenoptera

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

2012-01-01

Abstract 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.] PMID:22723471

Crustal thinning and exhumation along a fossil magma-poor distal margin preserved in Corsica: A hot rift to drift transition?

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Beltrando, Marco; Zibra, Ivan; Montanini, Alessandra; Tribuzio, Riccardo

2013-05-01

Rift-related thinning of continental basement along distal margins is likely achieved through the combined activity of ductile shear zones and brittle faults. While extensional detachments responsible for the latest stages of exhumation are being increasingly recognized, rift-related shear zones have never been sampled in ODP sites and have only rarely been identified in fossil distal margins preserved in orogenic belts. Here we report evidence of the Jurassic multi-stage crustal thinning preserved in the Santa Lucia nappe (Alpine Corsica), where amphibolite facies shearing persisted into the rift to drift transition. In this nappe, Lower Permian meta-gabbros to meta-gabbro-norites of the Mafic Complex are separated from Lower Permian granitoids of the Diorite-Granite Complex by a 100-250 m wide shear zone. Fine-grained syn-kinematic andesine + Mg-hornblende assemblages in meta-tonalites of the Diorite-Granite Complex indicate shearing at T = 710 ± 40 °C at P Lucia basement. These results imply that middle to lower crustal rocks can be cooled and exhumed rapidly in the last stages of rifting, when significant crustal thinning is accommodated in less than 5 Myr through the consecutive activity of extensional shear zones and detachment faults. High thermal gradients may delay the switch from ductile shear zone- to detachment-dominated crustal thinning, thus preventing the exhumation of middle and lower crustal rocks until the final stages of rifting.

Planktonic foraminifera-derived environmental DNA extracted from abyssal sediments preserves patterns of plankton macroecology

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R. Morard

2017-06-01

Full Text Available Deep-sea sediments constitute a unique archive of ocean change, fueled by a permanent rain of mineral and organic remains from the surface ocean. Until now, paleo-ecological analyses of this archive have been mostly based on information from taxa leaving fossils. In theory, environmental DNA (eDNA in the sediment has the potential to provide information on non-fossilized taxa, allowing more comprehensive interpretations of the fossil record. Yet, the process controlling the transport and deposition of eDNA onto the sediment and the extent to which it preserves the features of past oceanic biota remains unknown. Planktonic foraminifera are the ideal taxa to allow an assessment of the eDNA signal modification during deposition because their fossils are well preserved in the sediment and their morphological taxonomy is documented by DNA barcodes. Specifically, we re-analyze foraminiferal-specific metabarcodes from 31 deep-sea sediment samples, which were shown to contain a small fraction of sequences from planktonic foraminifera. We confirm that the largest portion of the metabarcode originates from benthic bottom-dwelling foraminifera, representing the in situ community, but a small portion (< 10 % of the metabarcodes can be unambiguously assigned to planktonic taxa. These organisms live exclusively in the surface ocean and the recovered barcodes thus represent an allochthonous component deposited with the rain of organic remains from the surface ocean. We take advantage of the planktonic foraminifera portion of the metabarcodes to establish to what extent the structure of the surface ocean biota is preserved in sedimentary eDNA. We show that planktonic foraminifera DNA is preserved in a range of marine sediment types, the composition of the recovered eDNA metabarcode is replicable and that both the similarity structure and the diversity pattern are preserved. Our results suggest that sedimentary eDNA could preserve the ecological structure of

Adaptation, plant evolution, and the fossil record

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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

Elucidating the affinities and habitat of ancient, widespread Cyperaceae: Volkeria messelensis gen. et sp. nov., a fossil mapanioid sedge from the Eocene of Europe.

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Smith, Selena Y; Collinson, Margaret E; Simpson, David A; Rudall, Paula J; Marone, Federica; Stampanoni, Marco

2009-08-01

The sedges (family Cyperaceae) are an economically and ecologically important monocot group dating back at least to the Paleocene. While modern genera are mostly unknown before the Oligocene, several extinct taxa are recognized as the earliest sedges. Their affinities have been unclear until now, because they are found as isolated, often abraded fruits or endocarps. Exceptionally preserved sedge fossils from the Middle Eocene of Messel, Germany yield more characters for identification. Fossil cyperacean infructescences with in situ pollen are recognized for the first time and show features of the early-divergent mapanioid sedges. Pollen resembles that of tribe Hypolytreae. Comparisons with extant taxa suggest the closest affinities with Hypolytrum and Mapania. However, the Messel fossils represent a distinct taxon, Volkeria messelensis gen. et sp. nov. Without the additional characters of infructescence and pollen, the Messel fruits would have been placed in the extinct genus Caricoidea, a typical Eocene sedge that was widespread across Eurasia. Similarities of fruit structure suggest that Caricoidea was also a mapanioid sedge. Mapanioid sedges are found today in tropical wet forests and swamps, a distribution suggesting that early sedges occupied a similar habitat, unlike many modern sedges, and were not precursors to open grassland vegetation.

A molecular characterization of a newly discovered megafaunal fossil site in North Canterbury, South Island, New Zealand

International Nuclear Information System (INIS)

Allentoft, M.E.; Scofield, R.P.; Oskam, C.L.; Hale, M.L.; Holdaway, R.N.; Bunce, M.

2012-01-01

In January 2008 an assemblage of large fossil bones was unearthed in a field near Waikari, North Canterbury, South Island, New Zealand. We describe this new fossil site, Rosslea, and provide an inventory of the excavated material. The bones were generally well preserved although stained deep brown, typical of peat preservation. Eight Rosslea bones were 14 C AMS dated and median calibrated ages ranged from 7839 to 1482 years BP. Ancient DNA was isolated from 14 bones and a single piece of eggshell. Genetic species identifications based on mitochondrial DNA matched those based on morphology, confirming that three species of extinct moa (Aves: Dinornithiformes) were present. Also, remains of an extinct South Island Adzebill (Aptornis defossor) were identified. The species composition in the Rosslea assemblage proved typical for the time and region but comparative analyses revealed that each of five major fossil deposits in the area displayed a significantly different relative abundance of moa taxa, despite their proximity and relative contemporaneity (all contain Holocene moa bones). Lastly, indications of DNA damage and failed attempts to amplify nuclear DNA indicated that DNA preservation at Rosslea was relatively poor compared to the preservation known from adjacent deposits. (author). 50 refs., 5 figs., 2 tabs.

Preservation in microbial mats: mineralization by a talc-like phase of a fish embedded in a microbial sarcophagus

Science.gov (United States)

Iniesto, Miguel; Zeyen, Nina; López-Archilla, Ana; Bernard, Sylvain; Buscalioni, Ángela; Guerrero, M. Carmen; Benzerara, Karim

2015-09-01

Microbial mats have been repeatedly suggested to promote early fossilization of macroorganisms. Yet, experimental simulations of this process remain scarce. Here, we report results of 5 year-long experiments performed onfish carcasses to document the influence of microbial mats on mineral precipitation during early fossilization. Carcasses were initially placed on top of microbial mats. After two weeks, fishes became coated by the mats forming a compact sarcophagus, which modified the microenvironment close to the corpses. Our results showed that these conditions favoured the precipitation of a poorly crystalline silicate phase rich in magnesium. This talc-like mineral phase has been detected in three different locations within the carcasses placed in microbial mats for more than 4 years: 1) within inner tissues, colonized by several bacillary cells; 2) at the surface of bones of the upper face of the corpse buried in the mat; and 3) at the surface of several bones such as the dorsal fin which appeared to be gradually replaced by the Mg-silicate phase. This mineral phase has been previously shown to promote bacteria fossilization. Here we provide first experimental evidence that such Mg-rich phase can also be involved in exceptional preservation of animals.

A new, exceptionally preserved juvenile specimen of Eusaurosphargis dalsassoi (Diapsida) and implications for Mesozoic marine diapsid phylogeny.

Science.gov (United States)

Scheyer, Torsten M; Neenan, James M; Bodogan, Timea; Furrer, Heinz; Obrist, Christian; Plamondon, Mathieu

2017-06-30

Recently it was suggested that the phylogenetic clustering of Mesozoic marine reptile lineages, such as thalattosaurs, the very successful fish-shaped ichthyosaurs and sauropterygians (including plesiosaurs), among others, in a so-called 'superclade' is an artefact linked to convergent evolution of morphological characters associated with a shared marine lifestyle. Accordingly, partial 'un-scoring' of the problematic phylogenetic characters was proposed. Here we report a new, exceptionally preserved and mostly articulated juvenile skeleton of the diapsid reptile, Eusaurosphargis dalsassoi, a species previously recovered within the marine reptile 'superclade', for which we now provide a revised diagnosis. Using micro-computed tomography, we show that besides having a deep skull with a short and broad rostrum, the most outstanding feature of the new specimen is extensive, complex body armour, mostly preserved in situ, along its vertebrae, ribs, and forelimbs, as well as a row of flat, keeled ventrolateral osteoderms associated with the gastralia. As a whole, the anatomical features support an essentially terrestrial lifestyle of the animal. A review of the proposed partial character 'un-scoring' using three published data matrices indicate that this approach is flawed and should be avoided, and that within the marine reptile 'superclade' E. dalsassoi potentially is the sister taxon of Sauropterygia.

Phytochemistry of the fossilized-cuticle frond Macroneuropteris macrophylla (Pennsylvanian seed fern, Canada)

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Zodrow, Erwin L. [Palaeobotanical Laboratory, Cape Breton University, Sydney, Nova Scotia, B1P 6L2 (Canada); D' Angelo, Jose A. [IANIGLA, CCT-CONICET-Mendoza, Avda. Ruiz Leal s/n Parque Gral. San Martin (5500) Mendoza (Argentina); Mastalerz, Maria [Indiana Geological Survey, Indiana University, Bloomington, IN, 47405-2208 (United States); Cleal, Christopher J. [Department of Biodiversity and Systematic Biology, National Museum of Wales, Cathays Park, Cardiff, CF10 3NP (United Kingdom); Keefe, Dale [Molecular Spectroscopy Research Laboratory, Department of Chemistry, Cape Breton University, Sydney, Nova Scotia (Canada)

2010-11-01

In Canada's Sydney Coalfield, specimens of the extinct Carboniferous seed fern Macroneuropteris macrophylla (Brongniart) invariably show preservation stages intermediate between compression and fossilized-cuticle, even concerning a single pinnule. In this interdisciplinary approach, we study a ca. 300 to 350 mm long fossilized-cuticle-preserved frond section of M. macrophylla (Brongniart) that represents about one third of the length of a frond that was originally 1 m long. Size and preservation allow us to study the phytochemistry of the cuticle biomacropolymers over the length of the frond to assess what impact, if any, results would have on Carboniferous palaeophytochemotaxonomy. For comparison, the phytochemistry of compressions with their extracted cuticles from the same species and the same sample locality is also investigated. We use solid- and liquid-state, semi-quantitative Fourier transform infrared spectroscopy (FTIR) for the chemical characterization of the frond. Based on our results, we infer an essentially uniform phytochemistry over the fossilized-cuticle frond, suggesting that only a single pinnule needs to be analyzed to get an overall phytochemical picture of the frond, which has been our long-time working hypothesis. We distinguish between phytochemistry and cutinization. The latter is much less pronounced above than below the frond dichotomy, and we suggest a palaeoecological cause, rather than differing pathways of organic matter transformation. Moreover, cuticles below and above the frond dichotomy have essentially the same epidermal pattern, but those from below have features that may have been an adaptation to prevent stomatal flooding during the tropical, rainy season. This study suggests that chemically the fossilized-cuticle is more similar to the compression than to the cuticle obtained from that compression of the same species which invites reevaluation of the classical compression concept. (author)

Phytochemistry of the fossilized-cuticle frond Macroneuropteris macrophylla (Pennsylvanian seed fern, Canada)

Science.gov (United States)

Zodrow, E.L.; D'Angelo, J. A.; Mastalerz, Maria; Cleal, C.J.; Keefe, D.

2010-01-01

In Canada's Sydney Coalfield, specimens of the extinct Carboniferous seed fern Macroneuropteris macrophylla (Brongniart) invariably show preservation stages intermediate between compression and fossilized-cuticle, even concerning a single pinnule. In this interdisciplinary approach, we study a ca. 300 to 350 mm long fossilized-cuticle-preserved frond section of M. macrophylla (Brongniart) that represents about one third of the length of a frond that was originally 1 m long. Size and preservation allow us to study the phytochemistry of the cuticle biomacropolymers over the length of the frond to assess what impact, if any, results would have on Carboniferous palaeophytochemotaxonomy. For comparison, the phytochemistry of compressions with their extracted cuticles from the same species and the same sample locality is also investigated. We use solid- and liquid-state, semi-quantitative Fourier transform infrared spectroscopy (FTIR) for the chemical characterization of the frond.Based on our results, we infer an essentially uniform phytochemistry over the fossilized-cuticle frond, suggesting that only a single pinnule needs to be analyzed to get an overall phytochemical picture of the frond, which has been our long-time working hypothesis. We distinguish between phytochemistry and cutinization. The latter is much less pronounced above than below the frond dichotomy, and we suggest a palaeoecological cause, rather than differing pathways of organic matter transformation. Moreover, cuticles below and above the frond dichotomy have essentially the same epidermal pattern, but those from below have features that may have been an adaptation to prevent stomatal flooding during the tropical, rainy season.This study suggests that chemically the fossilized-cuticle is more similar to the compression than to the cuticle obtained from that compression of the same species which invites reevaluation of the classical compression concept. ?? 2010 Elsevier B.V.

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

The Clare Quarry is located in the town of Florissant, Teller County, Colorado, approximately 30 miles west of Colorado Springs on State Highway 27. The elevation at the quarry face is 2500 meters ASL. Ar40/Ar39 dating of the upper beds of the Florissant Formation indicates an age of 34.07 +/- 0.10 Ma.An Oreodont fossil jaw and other mammalian fossils place the formation in the Chadronian Age.The basin in which the formation lies is undergirded by Wall Mountain Tuff dated at 37Ma, which sits on Pike's Peak Granite, which is dated at1080 Ma. In the Late Eocene the Florissant region was lacustrine in nature due to the damning of the river valley which runs north into Florissant. The ash and lahars from volcanic eruptions from the Thirty-nine Mile Volcano Field formed impoundments that produced shallow lakes for what is thought to been a period for 5000 years. Repeated ash falls placed plant matter and insect material in the lakes and streams that were formed intermittently during the period. The ash layers in the Florissant Formation are very fine grained, and contain diatomaceous mats that formed on the lake deposited ash layers aiding in the preservation of plant and insects material. Previous work on Florissant Fossils has been done by Lesquereaux (plants) 1878, Scudder (insects) 1890, and Mc Ginitie (plants) 1953. This project began 17 years ago and has consisted of collection trips ranging from one to eight days in the summers at a proprietary quarry owned land adjacent to The Florissant Fossil Beds National Monument. The collection consists of 2700 catalogued plants, insects, and fish fossils. Of this number, 513 are insect fossils (19% of the total collection). Quality of preservation ranges from very poor to very good with the average qualitative evaluation between poor to fair. The largest series identied to family are Tipulids (Craneflies) with 23 specimens in the series. In this series wing venation is often incomplete and smaller characters including

A new commelinid monocot seed fossil from the early Eocene previously identified as Solanaceae.

Science.gov (United States)

Särkinen, Tiina; Kottner, Sören; Stuppy, Wolfgang; Ahmed, Farah; Knapp, Sandra

2018-01-01

Fossils provide minimum age estimates for extant lineages. Here we critically evaluate Cantisolanum daturoides Reid & Chandler and two other early putative seed fossils of Solanaceae, an economically important plant family in the Asteridae. Three earliest seed fossil taxa of Solanaceae from the London Clay Formation (Cantisolanum daturoides) and the Poole and Branksome Sand Formations (Solanum arnense Chandler and Solanispermum reniforme Chandler) were studied using x-ray microcomputed tomography (MCT) and scanning electron microscopy (SEM). The MCT scans of Cantisolanum daturoides revealed a high level of pyrite preservation at the cellular level. Cantisolanum daturoides can be clearly excluded from Solanaceae and has more affinities to the commelinid monocots based on a straight longitudinal axis, a prominent single layer of relatively thin-walled cells in the testa, and a clearly differentiated micropyle surrounded by radially elongated and inwardly curved testal cells. While the MCT scans show no internal preservation in Solanum arnense and Solanispermum reniforme, SEM images show the presence of several characteristics that allow the placement of these taxa at the stem node of Solanaceae. Cantisolanum daturoides is likely a member of commelinid monocots and not Solanaceae as previously suggested. The earliest fossil record of Solanaceae is revised to consist of fruit fossil with inflated calyces from the early Eocene of Patagonia (52 Ma) and fossilized seeds from the early to mid-Eocene of Europe (48-46 Ma). The new identity for Cantisolanum daturoides does not alter a late Cretaceous minimum age for commelinids. © 2018 Botanical Society of America.

Fossil Platygastroidea in the National Museum of Natural History, Smithsonian Institution

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Platygastroid wasps preserved in Dominican amber and oil shale from the Kishenehn formation (Montana, USA) in the National Museum of Natural History are catalogued. Compression fossils in Kishenehn oil shale yield a specimen of Fidiobia, a specimen of Telenominae, and a specimen with a Scelio-type o...

Hydrogen movement and the next action: fossil fuels industry and sustainability economics

International Nuclear Information System (INIS)

Nejat Veziroglu, T.

1997-01-01

Since the hydrogen movement started in 1974, there has been progress in research, development, demonstration and commercialization activities, covering all aspects of the hydrogen energy system. In order to solve the interrelated problems of depletion of fossil fuels and the environmental impact of the combustion products of fossil fuels, it is desirable to speed up the conversion to the hydrogen energy system. Most established industries have joined the hydrogen movement. There is one exception: the fossil fuel industry. A call is made to the fossil fuel industry to join the hydrogen movement. It is also proposed to change the present economic system with a sustainability economics in order to account for environmental damage, recyclability and decommissioning, and thus, ensure a sustainable future. (Author)

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.

Embryology of Early Jurassic dinosaur from China with evidence of preserved organic remains.

Science.gov (United States)

Reisz, Robert R; Huang, Timothy D; Roberts, Eric M; Peng, ShinRung; Sullivan, Corwin; Stein, Koen; LeBlanc, Aaron R H; Shieh, DarBin; Chang, RongSeng; Chiang, ChengCheng; Yang, Chuanwei; Zhong, Shiming

2013-04-11

Fossil dinosaur embryos are surprisingly rare, being almost entirely restricted to Upper Cretaceous strata that record the late stages of non-avian dinosaur evolution. Notable exceptions are the oldest known embryos from the Early Jurassic South African sauropodomorph Massospondylus and Late Jurassic embryos of a theropod from Portugal. The fact that dinosaur embryos are rare and typically enclosed in eggshells limits their availability for tissue and cellular level investigations of development. Consequently, little is known about growth patterns in dinosaur embryos, even though post-hatching ontogeny has been studied in several taxa. Here we report the discovery of an embryonic dinosaur bone bed from the Lower Jurassic of China, the oldest such occurrence in the fossil record. The embryos are similar in geological age to those of Massospondylus and are also assignable to a sauropodomorph dinosaur, probably Lufengosaurus. The preservation of numerous disarticulated skeletal elements and eggshells in this monotaxic bone bed, representing different stages of incubation and therefore derived from different nests, provides opportunities for new investigations of dinosaur embryology in a clade noted for gigantism. For example, comparisons among embryonic femora of different sizes and developmental stages reveal a consistently rapid rate of growth throughout development, possibly indicating that short incubation times were characteristic of sauropodomorphs. In addition, asymmetric radial growth of the femoral shaft and rapid expansion of the fourth trochanter suggest that embryonic muscle activation played an important role in the pre-hatching ontogeny of these dinosaurs. This discovery also provides the oldest evidence of in situ preservation of complex organic remains in a terrestrial vertebrate.

A role for iron and oxygen chemistry in preserving soft tissues, cells and molecules from deep time.

Science.gov (United States)

Schweitzer, Mary H; Zheng, Wenxia; Cleland, Timothy P; Goodwin, Mark B; Boatman, Elizabeth; Theil, Elizabeth; Marcus, Matthew A; Fakra, Sirine C

2014-01-22

The persistence of original soft tissues in Mesozoic fossil bone is not explained by current chemical degradation models. We identified iron particles (goethite-αFeO(OH)) associated with soft tissues recovered from two Mesozoic dinosaurs, using transmission electron microscopy, electron energy loss spectroscopy, micro-X-ray diffraction and Fe micro-X-ray absorption near-edge structure. Iron chelators increased fossil tissue immunoreactivity to multiple antibodies dramatically, suggesting a role for iron in both preserving and masking proteins in fossil tissues. Haemoglobin (HB) increased tissue stability more than 200-fold, from approximately 3 days to more than two years at room temperature (25°C) in an ostrich blood vessel model developed to test post-mortem 'tissue fixation' by cross-linking or peroxidation. HB-induced solution hypoxia coupled with iron chelation enhances preservation as follows: HB + O2 > HB - O2 > -O2 > +O2. The well-known O2/haeme interactions in the chemistry of life, such as respiration and bioenergetics, are complemented by O2/haeme interactions in the preservation of fossil soft tissues.

Slow rates of degradation of osteocalcin: Green light for fossil bone protein?

Science.gov (United States)

Collins, M. J.; Gernaey, A. M.; Nielsen-Marsh, C. M.; Vermeer, C.; Westbroek, P.

2000-12-01

Our claim, published in this journal, for successful immunodetection of the protein osteocalcin in dinosaur bone has been challenged on the grounds that the findings are inconsistent with the kinetics of decomposition. Here we show that the close association of osteocalcin to the bone mineral vastly enhances its preservation potential relative to the same protein in aqueous solution. We conducted heating experiments (75 95 °C) of modern bone powder and monitored the survival of three different regions of osteocalcin (N-terminal, His4-Hyp9; C-terminal, Phe45-Val49; and the mid-region, Pro15-Glu31) with monoclonal antibodies. Extrapolation of our data to 10 °C ambient burial temperatures indicates that preservation of the γ-carboxylated mid-region in fossil bone cannot be excluded on kinetic grounds. Clearly, in situ sequence analysis will be the only method by which the preservation of fossil macromolecules will be unequivocally established. Nevertheless, our findings demonstrate the importance of mineral association to protein survival, as was borne out by an investigation of Holocene (ca. 6 ka) bones. Only in those samples with little recrystallization was the γ-carboxylated mid-region well preserved. These results imply that the future success of ancient biomolecule research largely depends on our understanding the interaction between these materials and their environment throughout diagenesis.

Remarkable preservation of microfossils and biofilms in mesoproterozoic silicified bitumen concretions from Northern China

DEFF Research Database (Denmark)

Wang, Xiaomei; Zhang, Shuichang; Wang, Huajian

2017-01-01

Prokaryotes, often generally referred to as “bacteria,” are the original and thus oldest life on Earth. They have shaped the chemical environment of the Earth, but they are difficult to find as ancient fossils due to their subtle structure. Here we report well-preserved fossilized microbial...

Teneur en uranium et datation U-Th des tissus osseux et dentaires fossiles de la grotte du Lazaret

Science.gov (United States)

Michel, Véronique; Falguères, Christophe; Yokoyama, Yuji

1997-09-01

Fossil bone and dental tissues from Lazaret cave and modern ones are here the subject of a comparative microscopical study. Porous tissues such as dentine and bone have retained their Haversian and Tomes canals respectively. However, cracked areas with calcite were detected, indicating a water percolation within porous tissues and an alteration of tissue in places. In addition, compact fossil enamel is particularly well preserved. These results are essential for U-Th and ESR dating application. Uranium contents, U-Th ages of two fossil mandibular tissues, two tibias and of six burnt fossil bones are presented and discussed.

Exploring the interior of cuticles and compressions of fossil plants by FIB-SEM milling and image microscopy.

Science.gov (United States)

Sender, L M; Escapa, I; Benedetti, A; Cúneo, R; Diez, J B

2018-01-01

We present the first study of cuticles and compressions of fossil leaves by Focused Ion Beam Scanning Electron Microscopy (FIB-SEM). Cavities preserved inside fossil leaf compressions corresponding to substomatal chambers have been observed for the first time and several new features were identified in the cross-section cuts. These results open a new way in the investigation of the three-dimensional structures of both micro- and nanostructural features of fossil plants. Moreover, the application of the FIB-SEM technique to both fossils and extant plant remains represent a new source of taxonomical, palaeoenvironmental and palaeoclimatic information. © 2017 The Authors Journal of Microscopy © 2017 Royal Microscopical Society.

Preservation of rodent bones from El Harhoura 2 cave (Morocco, Neolithic - Middle Palaeolithic): Microstructure, mineralogy, crystallinity and composition

Science.gov (United States)

Farre, Bastien; Massard, Pierre; Nouet, Julius; Dauphin, Yannicke

2014-04-01

Thin sections, scanning electron microscopy (SEM), diffraction X (DRX) and infrared spectrometry (FTIR) have been used to study the structure, mineralogy, crystallinity and bulk composition of fossil rodent long bones extracted from a succession of sedimentary layers in a cave from Morocco (Neolithic - Middle Palaeolithic, El Harhoura 2). The microstructure of fossil bones is well-preserved at this scale of observation, and encrusted deposits are rare. All bones are preserved in apatite, but the crystallinity is modified, as well as the crystallite shape, the organic content and the organic-mineral ratio. No fluor enrichment has been observed. Alone or together, the studied parameters do not show a regular trend from the upper to the lower layers of the cave. The preservation of the fossil bones does not confirm the sequence of arid and humid periods inferred from taphonomic analyses.

Origin and monitoring of pollutants in fossil-fuel flames

International Nuclear Information System (INIS)

Chigier, N.A.

1976-01-01

A review is given of the origin of pollutants in fossil-fuel flames. Burning of fossil fuels is the major cause of air pollution and significant reductions in levels of environmental pollution can be achieved by more effective control of combustion systems. The chemical kinetics of formation of unburned hydrocarbons, oxides of nitrogen, carbon monoxide and particulate matter are described, as well as the reactions which can lead to oxidation and destruction of these pollutants within the flame. The important influence of mixing and aerodynamics is discussed, together with methods of mathematical modelling and prediction methods. Practical problems arising in gas turbine engines, spark ignition engines and diesel engines are investigated in order to minimize the emission of pollutants while preserving fuel economy. (author)

Functional groups of fossil marattialeans: Chemotaxonomic implications for Pennsylvanian tree ferns and pteridophylls

Science.gov (United States)

Psenicka, J.; Zodrow, E.L.; Mastalerz, Maria; Bek, J.

2005-01-01

Marattialean-fossil foliage, assigned to Pecopteris Brongniart, was an important and widespread floral component in Late Pennsylvanian mires, with phylogenetic affinity to extant marattialean taxa in tropical regions. Marattialean fossil taxonomy is, however, still uncertain. Specimens from the Pilsen limnic Basin, Westphalian D, Czech Republic, represent fertile marattialean foliage of Pecopteris (Asterotheca) nyranensis and Pecopteris (Asterotheca) miltonii, and sterile foliage of Pecopteris aspidioides and Pecopteris polypodioides. Taxonomic parameters for their assignments included cuticle, stomatal morphologies (studied for the first time), and in situ reproductive organs and spores. Chemotaxonomic interpretations hinge on fidelity of preservation of compounds, or molecular fragments thereof, that were synthesized by the once-living plants. This preservation state was possibly due to the thermal history (maximum temperature of 130 ??C) in the Pilsen Basin, acidic preservation conditions, lithology and facies stability. Although subtle, the four pecopterid species are differentiable from one another by combined FTIR characteristics, supporting taxonomy. The ratio of CH2/CH3 is hypothesized to be a chemotaxonomic parameter for Pennsylvanian pteridophylls, both in seed and true ferns that have previously been studied. It will, however, be supplemented by additional biochemical markers. ?? 2004 Elsevier B.V. All rights reserved.

Mid-Cretaceous amber fossils illuminate the past diversity of tropical lizards

Science.gov (United States)

Daza, Juan D.; Stanley, Edward L.; Wagner, Philipp; Bauer, Aaron M.; Grimaldi, David A.

2016-01-01

Modern tropical forests harbor an enormous diversity of squamates, but fossilization in such environments is uncommon and little is known about tropical lizard assemblages of the Mesozoic. We report the oldest lizard assemblage preserved in amber, providing insight into the poorly preserved but potentially diverse mid-Cretaceous paleotropics. Twelve specimens from the Albian-Cenomanian boundary of Myanmar (99 Ma) preserve fine details of soft tissue and osteology, and high-resolution x-ray computed tomography permits detailed comparisons to extant and extinct lizards. The extraordinary preservation allows several specimens to be confidently assigned to groups including stem Gekkota and stem Chamaleonidae. Other taxa are assignable to crown clades on the basis of similar traits. The detailed preservation of osteological and soft tissue characters in these specimens may facilitate their precise phylogenetic placement, making them useful calibration points for molecular divergence time estimates and potential keys for resolving conflicts in higher-order squamate relationships. PMID:26973870

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.

The Cova des Pas de Vallgornera (Llucmajor, Mallorca: a singular deposit bearing an exceptional well preserved Early Pleistocene vertebrate fauna

Directory of Open Access Journals (Sweden)

Pere Bover

2014-05-01

Full Text Available The Cova des Pas de Vallgornera is the longest cave of Mallorca (Balearic Islands, Western Mediterranean and one of the 30 longest caves in the world. The exploration of one of the galleries allowed the discovery of a fossiliferous deposit of vertebrate remains in a remarkable preservation state. The fossil faunal complex found in this gallery is composed of up to 5 mammalian species (Myotragus aff. kopperi, Hypnomys onicensis, Nesiotites aff. ponsi, Rhinolophus aff. mehelyi and Pipistrellus sp., at least 14 bird species (among them two Mallorcan endemic taxa: Pica mourerae and Athene vallgornerensis, one reptile (Podarcis aff. lilfordi and one amphibian (Discoglossus sp.. This faunal composition is similar to the one recorded in the Pedrera de s’Ònix, a well known deposit from the Early Pleistocene of Mallorca, and shared morphological characteristics between taxa of both deposits suggest that the chronology of the Cova des Pas de Vallgornera should be considered Early Pleistocene as well. Both taxonomical analysis and chronology of this fauna furnished information on some speleological aspects of the cave.

Implications of a fossil stickleback assemblage for Darwinian gradualism.

Science.gov (United States)

Bell, M A

2009-11-01

Darwin postulated that a complete fossil record would contain numerous gradual transitions between ancestral and descendant species, but 150 years after publication of The Origin of Species, few such transitions have materialized. The fossil stickleback Gasterosteus doryssus and the deposit in which it occurs provide excellent conditions to detect such transitions. Abundant, well-preserved fossils occur in a stratigraphic setting with fine temporal resolution. The paleoecology of G. doryssus resembles the ecology of modern lakes that harbour the phenotypically similar three-spined stickleback Gasterosteus aculeatus. Gasterosteus aculeatus are primitively highly armoured, but G. doryssus comprised two contemporaneous biological species with relatively weak armour, including a near-shore, benthic feeder (benthic) and an offshore planktivore (limnetic). The benthic species expanded its range into the limnetic zone of the lake, where it apparently switched to planktivory and evolved reduced armour within c. 5000 years in response to directional selection. Although gradual evolution of mean phenotypes occurred, a single major gene caused much of evolutionary change of the pelvic skeleton. Thus, Darwin's expectation that transitions between species in the fossil record would be gradual was met at a fine time scale, but for pelvic structure, a well-studied trait, his expectation that gradual change would depend entirely on numerous, small, heritable differences among individuals was incorrect.

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

Science.gov (United States)

Wing, S. L.

2011-12-01

analysis of early Cenozoic floras from the Rocky Mountain region. Paleocene climates across the region were warm with warm winters. Mean annual temperature estimates vary from 10-18 °C depending on the time and place, and ground-freezing climates occurred only north of 40-45 °N. Plants and sedimentary environments suggest low altitude deposition, though floras are not as homogeneous as once thought, suggesting barriers existed. Eocene climates were warmer, with mean annual temperature estimates of 14-25 °C, and ground-freezing climates occurring only north of the Canadian border. Paleobotanical evidence for substantial paleoelevations in basinal areas is weak, but volcanic terrains to the west preserve floras that suggest higher paleoelevations, even in the early and middle Eocene. The terms "frost-free" and "tropical" have sometimes been used to describe Eocene climate and vegetation of the northern U.S. Rocky Mountains, but are probably not justified, with the possible exception of the the warmest early Eocene hyperthermal events at low paleoelevation.

21 CFR 146.152 - Orange juice with preservative.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Orange juice with preservative. 146.152 Section... Fruit Juices and Beverages § 146.152 Orange juice with preservative. (a) Orange juice with preservative... of orange juice for manufacturing as provided for in § 146.151, except that a preservative is added...

An exceptionally preserved transitional lungfish from the lower permian of Nebraska, USA, and the origin of modern lungfishes.

Directory of Open Access Journals (Sweden)

Jason D Pardo

Full Text Available Complete, exceptionally-preserved skulls of the Permian lungfish Persephonichthys chthonica gen. et sp. nov. are described. Persephonichthys chthonica is unique among post-Devonian lungfishes in preserving portions of the neurocranium, permitting description of the braincase of a stem-ceratodontiform for the first time. The completeness of P. chthonica permits robust phylogenetic analysis of the relationships of the extant lungfish lineage within the Devonian lungfish diversification for the first time. New analyses of the relationships of this new species within two published matrices using both maximum parsimony and Bayesian inference robustly place P. chthonica and modern lungfishes within dipterid-grade dipnoans rather than within a clade containing Late Devonian 'phaneropleurids' and common Late Paleozoic lungfishes such as Sagenodus. Monophyly of post-Devonian lungfishes is not supported and the Carboniferous-Permian taxon Sagenodus is found to be incidental to the origins of modern lungfishes, suggesting widespread convergence in Late Paleozoic lungfishes. Morphology of the skull, hyoid arch, and pectoral girdle suggests a deviation in feeding mechanics from that of Devonian lungfishes towards the more dynamic gape cycle and more effective buccal pumping seen in modern lungfishes. Similar anatomy observed previously in 'Rhinodipterus' kimberyensis likely represents an intermediate state between the strict durophagy observed in most Devonian lungfishes and the more dynamic buccal pump seen in Persephonichthys and modern lungfishes, rather than adaptation to air-breathing exclusively.

An Exceptionally Preserved Transitional Lungfish from the Lower Permian of Nebraska, USA, and the Origin of Modern Lungfishes

Science.gov (United States)

Pardo, Jason D.; Huttenlocker, Adam K.; Small, Bryan J.

2014-01-01

Complete, exceptionally-preserved skulls of the Permian lungfish Persephonichthys chthonica gen. et sp. nov. are described. Persephonichthys chthonica is unique among post-Devonian lungfishes in preserving portions of the neurocranium, permitting description of the braincase of a stem-ceratodontiform for the first time. The completeness of P. chthonica permits robust phylogenetic analysis of the relationships of the extant lungfish lineage within the Devonian lungfish diversification for the first time. New analyses of the relationships of this new species within two published matrices using both maximum parsimony and Bayesian inference robustly place P. chthonica and modern lungfishes within dipterid-grade dipnoans rather than within a clade containing Late Devonian ‘phaneropleurids’ and common Late Paleozoic lungfishes such as Sagenodus. Monophyly of post-Devonian lungfishes is not supported and the Carboniferous-Permian taxon Sagenodus is found to be incidental to the origins of modern lungfishes, suggesting widespread convergence in Late Paleozoic lungfishes. Morphology of the skull, hyoid arch, and pectoral girdle suggests a deviation in feeding mechanics from that of Devonian lungfishes towards the more dynamic gape cycle and more effective buccal pumping seen in modern lungfishes. Similar anatomy observed previously in ‘Rhinodipterus’ kimberyensis likely represents an intermediate state between the strict durophagy observed in most Devonian lungfishes and the more dynamic buccal pump seen in Persephonichthys and modern lungfishes, rather than adaptation to air-breathing exclusively. PMID:25265394

A new U-Pb zircon age and a volcanogenic model for the early Permian Chemnitz Fossil Forest

Science.gov (United States)

Luthardt, Ludwig; Hofmann, Mandy; Linnemann, Ulf; Gerdes, Axel; Marko, Linda; Rößler, Ronny

2018-04-01

The Chemnitz Fossil Forest depicts one of the most completely preserved forest ecosystems in late Paleozoic Northern Hemisphere of tropical Pangaea. Fossil biota was preserved as a T0 taphocoenosis resulting from the instantaneous entombment by volcanic ashes of the Zeisigwald Tuff. The eruption depicts one of the late magmatic events of post-variscan rhyolitic volcanism in Central Europe. This study represents a multi-method evaluation of the pyroclastic ejecta encompassing sedimentological and (isotope) geochemical approaches to shed light on magmatic and volcanic processes, and their role in preserving the fossil assemblage. The Zeisigwald Tuff pyroclastics (ZTP) reveal a radiometric age of 291 ± 2 Ma, pointing to a late Sakmarian/early Artinskian (early Permian) stratigraphic position for the Chemnitz Fossil Forest. The initial eruption was of phreatomagmatic style producing deposits of cool, wet ashes, which deposited from pyroclastic fall out and density currents. Culmination of the eruption is reflected by massive hot and dry ignimbrites. Whole-rock geochemistry and zircon grain analysis show that pyroclastic deposits originated from a felsic, highly specialised magma, which underwent advanced fractionation, and is probably related to post-Carboniferous magmatism in the Western Erzgebirge. The ascending magma recycled old cadomic crust of the Saxo-thuringian zone, likely induced by a mantle-derived heat flow during a phase of post-variscan crustal delamination. Geochemical trends within the succession of the basal pyroclastic horizons reflect inverse zonation of the magma chamber and provide evidence for the continuous eruption and thus a simultaneous burial of the diverse ecosystem.

Early Pliocene anuran fossils from Kanapoi, Kenya, and the first fossil record for the African burrowing frog Hemisus (Neobatrachia: Hemisotidae).

Science.gov (United States)

Delfino, Massimo

2017-07-13

Isolated amphibian bones from the early Pliocene of Kanapoi (West Turkana, Kenya) help to improve the scarce fossil record of the late Neogene and Quaternary amphibians from East Africa. All currently available 579 bones are referable exclusively to the Anura (frogs and toads). More than half of the remains (366) are identified as Hemisus cf. Hemisus marmoratus, an extant species that still inhabits Kenya, but apparently not the northwest of the country and the Turkana area in particular. The rest of the remains are identified simply as Anura indet. because of poor preservation or non congruence with the relatively few African extant taxa whose osteology is known in detail. The Hemisus material represents the first fossil record for Hemisotidae, an endemic African family of peculiar, head-first burrowing frogs, whose sister taxon relationships indicate a divergence from brevicipitids in the Late Cretaceous or early Paleocene. The ecological requirements of extant H. marmoratus suggest that the Kanapoi area surrounding the fluvial and deltaic settings, from where the fossil remains of vertebrates were buried, was likely a grassland or relatively dry, open low tree-shrub savanna. Copyright © 2017 Elsevier Ltd. All rights reserved.

Fossil butterflies, calibration points and the molecular clock (Lepidoptera: Papilionoidea).

Science.gov (United States)

Jong, Rienk DE

2017-05-25

Fossil butterflies are extremely rare. Yet, they are the only direct evidence of the first appearance of particular characters and as such, they are crucial for calibrating a molecular clock, from which divergence ages are estimated. In turn, these estimates, in combination with paleogeographic information, are most important in paleobiogeographic considerations. The key issue here is the correct allocation of fossils on the phylogenetic tree from which the molecular clock is calibrated.The allocation of a fossil on a tree should be based on an apomorphic character found in a tree based on extant species, similar to the allocation of a new extant species. In practice, the latter is not done, at least not explicitly, on the basis of apomorphy, but rather on overall similarity or on a phylogenetic analysis, which is not possible for most butterfly fossils since they usually are very fragmentary. Characters most often preserved are in the venation of the wings. Therefore, special attention is given to possible apomorphies in venational characters in extant butterflies. For estimation of divergence times, not only the correct allocation of the fossil on the tree is important, but also the tree itself influences the outcome as well as the correct determination of the age of the fossil. These three aspects are discussed.        All known butterfly fossils, consisting of 49 taxa, are critically reviewed and their relationship to extant taxa is discussed as an aid for correctly calibrating a molecular clock for papilionoid Lepidoptera. In this context some aspects of age estimation and biogeographic conclusions are briefly mentioned in review. Specific information has been summarized in four appendices.

X-ray photoelectron emission spectromicroscopic analysis of arborescent lycopsid cell wall composition and Carboniferous coal ball preservation

Energy Technology Data Exchange (ETDEWEB)

Boyce, C. Kevin [Department of the Geophysical Sciences, University of Chicago, Chicago, IL 60637 (United States); Abrecht, Mike; Zhou, Dong; Gilbert, P.U.P.A. [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States)

2010-08-01

Two alternative processes complicate understanding of the biochemical origins and geochemical alteration of organic matter over geologic time: selective preservation of original biopolymers and in situ generation of new geopolymers. One of the best constrained potential sources of bio- and geochemical information about extinct fossil plants is frequently overlooked. Permineralized anatomically preserved plant fossils allow analysis of individual cell and tissue types that have an original biochemical composition already known from living plants. The original composition of more enigmatic fossils can be constrained by geochemical comparisons to tissues of better understood fossils from the same locality. This strategy is possible using synchrotron-based techniques for submicron-scale imaging with X-rays over a range of frequencies in order to provide information concerning the relative abundance of different organic bonds with X-ray Absorption Near Edge Spectroscopy. In this study, X-ray PhotoElectron Emission spectroMicroscopy (X-PEEM) was used to analyze the tissues of Lepidodendron, one of the lycopsid trees that were canopy dominants of many Pennsylvanian coal swamp forests. Its periderm or bark - the single greatest biomass contributor to many Late Paleozoic coals - is found to have a greater aliphatic content and an overall greater density of organic matter than lignified wood. Because X-PEEM allows simultaneous analysis of organic matter and matrix calcite in fully mineralized fossils, this technique also has great potential for analysis of fossil preservation, including documentation of significant traces of organic matter entrained in the calcite crystal fabric that fills the cell lumens. (author)

Icnology and fossils of the 'Palacio Member of the Asencio Formation' (superior cretaceous - inferior tertiary of Uruguay)

International Nuclear Information System (INIS)

Gonzalez, M.; Tofalo, O.; Pazos, P.

1998-01-01

Observations at three different quarries outcrops of the Del Palacio Member of the Asencio Formation near Nueva Palmira suggest that insect fossil nests occur in tiered paleosols, in which two different subborizons can be recognized. One of them showing columnar structure containing mostly Palmiraichmus castellonsi and Teisseirei barattinia preserved in their origininal position in many of them containing fossil nests rotated from their original position. This level is characterized by the abundance of Caprinisphaera ispp, Monesichnus ameghinoi and Uruguay ispp. Although rain forest conditions, the trace fossil association suggests that insects nested more likely under ecological conditions compatible with herbaceous. (author)

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.

The late Paleozoic ecological-evolutionary laboratory, a land-plant fossil record perspective

NARCIS (Netherlands)

Looy, Cindy; Kerp, Hans; Duijnstee, Ivo; DiMichele, Bill

2014-01-01

In this essay we examine the fossil record of land plants, focusing on the late Paleozoic. We explore the nature of this record in terms of what is preserved, where, why and with what biases. And as a consequence, how it can be used to answer questions posed at various spatial and temporal scales,

Fossils mollusc asemblage found at Zagarzazu, marine Pleistocene, Uruguay

International Nuclear Information System (INIS)

Rojas, A. . E mail: alejandra@fcien.edu.uy

2004-01-01

There are presented the results of the paleoecological analysis of the mollusc assemblage found at Zagarzazu, Colonia department. The fossils are well preserved, arranged in thin shell-beds with some specimens in life position. The assemblage is indicative of higher temperatures than present, and a strong marine influence. It is important to stress that new thermophilic molluscs for the marine Quaternary were found and that this locality represents a new Pleistocene marine record in Uruguay [es

The Completeness of the Fossil Record of Mesozoic Birds: Implications for Early Avian Evolution

Science.gov (United States)

Brocklehurst, Neil; Upchurch, Paul; Mannion, Philip D.; O'Connor, Jingmai

2012-01-01

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 interval but

Systematics, phylogeny, and taphonomy of ghost shrimps (Decapoda): a perspective from the fossil record

Science.gov (United States)

Klompmaker, Adiël A.

2016-01-01

Ghost shrimps of Callianassidae and Ctenochelidae are soft-bodied, usually heterochelous decapods representing major bioturbators of muddy and sandy (sub)marine substrates. Ghost shrimps have a robust fossil record spanning from the Early Cretaceous (~ 133 Ma) to the Holocene and their remains are present in most assemblages of Cenozoic decapod crustaceans. Their taxonomic interpretation is in flux, mainly because the generic assignment is hindered by their insufficient preservation and disagreement in the biological classification. Furthermore, numerous taxa are incorrectly classified within the catch-all taxon Callianassa. To show the historical patterns in describing fossil ghost shrimps and to evaluate taphonomic aspects influencing the attribution of ghost shrimp remains to higher level taxa, a database of all fossil species treated at some time as belonging to the group has been compiled: 250 / 274 species are considered valid ghost shrimp taxa herein. More than half of these taxa (160 species, 58.4%) are known only from distal cheliped elements, i.e., dactylus and / or propodus, due to the more calcified cuticle locally. Rarely, ghost shrimps are preserved in situ in burrows or in direct association with them, and several previously unpublished occurrences are reported herein. For generic assignment, fossil material should be compared to living species because many of them have modern relatives. Heterochely, intraspecific variation, ontogenetic changes and sexual dimorphism are all factors that have to be taken into account when working with fossil ghost shrimps. Distal elements are usually more variable than proximal ones. Preliminary results suggest that the ghost shrimp clade emerged not before the Hauterivian (~ 133 Ma). The divergence of Ctenochelidae and Paracalliacinae is estimated to occur within the interval of Hauterivian to Albian (133–100 Ma). Callichirinae and Eucalliacinae likely diverged later during the Late Cretaceous (100–66 Ma

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,…

Testing New Proxies for Photosymbiosis in the Fossil Record

Science.gov (United States)

Tornabene, C.; Martindale, R. C.; Schaller, M. F.

2015-12-01

Photosymbiosis is a mutualistic relationship that many corals have developed with dinoflagellates called zooxanthellae. The dinoflagellates, of the genus Symbiodinium, photosynthesize and provide corals with most of their energy, while in turn coral hosts live in waters where zooxanthellae have optimal exposure to sunlight. Thanks to this relationship, symbiotic corals calcify faster than non-symbiotic corals. Photosymbiosis is therefore considered the evolutionary innovation that allowed corals to become major reef-builders through geological time.This relationship is extremely difficult to study. Zooxanthellae, which are housed in the coral tissue, are not preserved in fossil coral skeletons, thus determining whether corals had symbionts requires a robust proxy. In order to address this critical question, the goal of this research is to test new proxies for ancient photosymbiosis. Currently the project is focused on assessing the nitrogen (δ15N) isotopes of corals' organic matrices, sensu Muscatine et al. (2005), as well as carbon and oxygen (δ13C, δ18O) isotopes of fossil coral skeletons. Samples from Modern, Pleistocene, Oligocene and Triassic coral skeletons were analyzed to test the validity of these proxies. Coral samples comprise both (interpreted) symbiotic and non-symbiotic fossil corals from the Oligocene and Triassic as well as symbiotic fossil corals from the Modern and Pleistocene to corroborate our findings with the results of Muscatine et al. (2005). Samples were tested for diagenesis through petrographic and scanning electron microscope (SEM) analyses to avoid contamination. Additionally, a novel technique that has not yet been applied to the fossil record was tested. The technique aims to recognize dinosterol, a dinoflagellate biomarker, in both modern and fossil coral samples. The premise of this proxy is that symbiotic corals should contain the dinoflagellate biomarker, whereas those lacking symbionts should lack dinosterol. Results from this

Penetrative trace fossils from the late Ediacaran of Mongolia: early onset of the agronomic revolution

Science.gov (United States)

Oji, Tatsuo; Dornbos, Stephen Q.; Yada, Keigo; Hasegawa, Hitoshi; Gonchigdorj, Sersmaa; Mochizuki, Takafumi; Takayanagi, Hideko; Iryu, Yasufumi

2018-02-01

The Cambrian radiation of complex animals includes a dramatic increase in the depth and intensity of bioturbation in seafloor sediment known as the `agronomic revolution'. This bioturbation transition was coupled with a shift in dominant trace fossil style from horizontal surficial traces in the late Precambrian to vertically penetrative trace fossils in the Cambrian. Here we show the existence of the first vertically penetrative trace fossils from the latest Ediacaran: dense occurrences of the U-shaped trace fossil Arenicolites from late Precambrian marine carbonates of Western Mongolia. Their Ediacaran age is established through stable carbon isotope chemostratigraphy and their occurrence stratigraphically below the first appearance of the trace fossil Treptichnus pedum. These Arenicolites are large in diameter, penetrate down to at least 4 cm into the sediment, and were presumably formed by the activity of bilaterian animals. They are preserved commonly as paired circular openings on bedding planes with maximum diameters ranging up to almost 1 cm, and as U- and J-shaped tubes in vertical sections of beds. Discovery of these complex penetrative trace fossils demonstrates that the agronomic revolution started earlier than previously considered.

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).

New Mesozoic and Cenozoic fossils from Ecuador: Invertebrates, vertebrates, plants, and microfossils

Science.gov (United States)

Cadena, Edwin A.; Mejia-Molina, Alejandra; Brito, Carla M.; Peñafiel, Sofia; Sanmartin, Kleber J.; Sarmiento, Luis B.

2018-04-01

Ecuador is well known for its extensive extant biodiversity, however, its paleobiodiversity is still poorly explored. Here we report seven new Mesozoic and Cenozoic fossil localities from the Pacific coast, inter-Andean depression and Napo basin of Ecuador, including vertebrates, invertebrates, plants, and microfossils. The first of these localities is called El Refugio, located near the small town of Chota, Imbabura Province, from where we report several morphotypes of fossil leaves and a mycetopodid freshwater mussel of the Upper Miocene Chota Formation. A second site is also located near the town of Chota, corresponding to potentially Pleistocene to Holocene lake deposits from which we report the occurrence of leaves and fossil diatoms. A third locality is at the Pacific coast of the country, near Rocafuerte, a town in Esmeraldas Province, from which we report a late Miocene palm leaf. We also report the first partially articulated skull with teeth from a Miocene scombridid (Mackerels) fish from El Cruce locality, and completely preserved seeds from La Pila locality, both sites from Manabí Province. Two late Cretaceous fossil sites from the Napo Province, one near Puerto Napo showing a good record of fossil shrimps and a second near the town of Loreto shows the occurrence of granular amber and small gymnosperms seeds and cuticles. All these new sites and fossils show the high potential of the sedimentary sequences and basins of Ecuador for paleontological studies and for a better understanding of the fossil record of the country and northern South America.

Melanins in Fossil Animals: Is It Possible to Infer Life History Traits from the Coloration of Extinct Species?

OpenAIRE

Negro, Juan J.; Fynlayson, Clive; Galván, Ismael

2018-01-01

Paleo-colour scientists have recently made the transition from describing melanin-based colouration in fossil specimens to inferring life-history traits of the species involved. Two such cases correspond to counter-shaded dinosaurs: dark-coloured due to melanins dorsally, and light-coloured ventrally. We believe that colour reconstruction of fossils based on the shape of preserved microstructures—the majority of paleo-colour studies involve melanin granules—is not without risks. In addition, ...

Preservation of biological information in thermal spring deposits - Developing a strategy for the search for fossil life on Mars

Science.gov (United States)

Walter, M. R.; Des Marais, David J.

1993-01-01

Paleobiological experience on earth is used here to develop a search strategy for fossil life on Mars. In particular, the exploration of thermal spring deposits is proposed as a way to maximize the chance of finding fossil life on Mars. As a basis for this suggestion, the characteristics of thermal springs are discussed in some detail.

The oldest known digestive system consisting of both paired digestive glands and a crop from exceptionally preserved trilobites of the Guanshan Biota (Early Cambrian, China.

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Melanie J Hopkins

Full Text Available The early Cambrian Guanshan biota of eastern Yunnan, China, contains exceptionally preserved animals and algae. Most diverse and abundant are the arthropods, of which there are at least 11 species of trilobites represented by numerous specimens. Many trilobite specimens show soft-body preservation via iron oxide pseudomorphs of pyrite replacement. Here we describe digestive structures from two species of trilobite, Palaeolenus lantenoisi and Redlichia mansuyi. Multiple specimens of both species contain the preserved remains of an expanded stomach region (a "crop" under the glabella, a structure which has not been observed in trilobites this old, despite numerous examples of trilobite gut traces from other Cambrian Lagerstätten. In addition, at least one specimen of Palaeolenus lantenoisi shows the preservation of an unusual combination of digestive structures: a crop and paired digestive glands along the alimentary tract. This combination of digestive structures has also never been observed in trilobites this old, and is rare in general, with prior evidence of it from one juvenile trilobite specimen from the late Cambrian Orsten fauna of Sweden and possibly one adult trilobite specimen from the Early Ordovician Fezouata Lagerstätte. The variation in the fidelity of preservation of digestive structures within and across different Lagerstätten may be due to variation in the type, quality, and point of digestion of food among specimens in addition to differences in mode of preservation. The presence and combination of these digestive features in the Guanshan trilobites contradicts current models of how the trilobite digestive system was structured and evolved over time. Most notably, the crop is not a derived structure as previously proposed, although it is possible that the relative size of the crop increased over the evolutionary history of the clade.

The oldest known digestive system consisting of both paired digestive glands and a crop from exceptionally preserved trilobites of the Guanshan Biota (Early Cambrian, China).

Science.gov (United States)

Hopkins, Melanie J; Chen, Feiyang; Hu, Shixue; Zhang, Zhifei

2017-01-01

The early Cambrian Guanshan biota of eastern Yunnan, China, contains exceptionally preserved animals and algae. Most diverse and abundant are the arthropods, of which there are at least 11 species of trilobites represented by numerous specimens. Many trilobite specimens show soft-body preservation via iron oxide pseudomorphs of pyrite replacement. Here we describe digestive structures from two species of trilobite, Palaeolenus lantenoisi and Redlichia mansuyi. Multiple specimens of both species contain the preserved remains of an expanded stomach region (a "crop") under the glabella, a structure which has not been observed in trilobites this old, despite numerous examples of trilobite gut traces from other Cambrian Lagerstätten. In addition, at least one specimen of Palaeolenus lantenoisi shows the preservation of an unusual combination of digestive structures: a crop and paired digestive glands along the alimentary tract. This combination of digestive structures has also never been observed in trilobites this old, and is rare in general, with prior evidence of it from one juvenile trilobite specimen from the late Cambrian Orsten fauna of Sweden and possibly one adult trilobite specimen from the Early Ordovician Fezouata Lagerstätte. The variation in the fidelity of preservation of digestive structures within and across different Lagerstätten may be due to variation in the type, quality, and point of digestion of food among specimens in addition to differences in mode of preservation. The presence and combination of these digestive features in the Guanshan trilobites contradicts current models of how the trilobite digestive system was structured and evolved over time. Most notably, the crop is not a derived structure as previously proposed, although it is possible that the relative size of the crop increased over the evolutionary history of the clade.

Phymosoma maastrichtensis spec. nov., a fossil echinoid from the Cretaceous of Maastricht (Echinacea, Phymosomatoida, Phymosomatidae)

NARCIS (Netherlands)

Engel, H.

1972-01-01

A beautifully preserved fragment of the test of a fossil Echinoid from the Maestrichtian Cretaceous, found at Belvédère, Caberg and kept in the Natuurhistorisch Museum, Maastricht under no. 1340, differs from the other species of the genus Phymosoma, hitherto described (cf. Fell & Pawson, 1966: U

Physicochemical and biochemical characterization of non-biodegradable cellulose in Miocene gymnosperm wood from the Entre-Sambre-et-Meuse, Southern Belgium

Energy Technology Data Exchange (ETDEWEB)

Lechien, Valerie; Rodriguez, Christian; Ongena, Marc; Hiligsmann, Serge; Thonart, Philippe [Liege Univ., Walloon Center of Industrial Biology, Gembloux (Belgium); Rulmont, Andre [Liege Univ., Chemistry Dept., Liege (Belgium)

2006-11-15

Specimens of Miocene fossil wood from the Entre-Sambre-et-Meuse karsts (southern Belgium) were examined using physicochemical and biochemical techniques in order to understand the reasons for the exceptional preservation of these fossilized remains after 15 million years. Structural and chemical changes were assessed by comparing the structural features of the fossil samples with those of their modern counterpart, Metasequoia. Solid state {sup 13} C nuclear magnetic resonance (NMR) and microscopic analysis showed good preservation of the cellulose structure in the fossil wood from the Florennes peat deposit. Despite the substantial cellulose fraction available in the fossil tissue, an enzymatic degradation test and a biochemical methane potential assay showed that the fossil cellulose could not be degraded by cellulases and anaerobic microorganisms usually involved in the biodegradation of organic matter. Moreover, the cellulose structure (crystallinity and surface area) seemed to have no effect on cellulose biodegradability in these Miocene fossil wood samples. On the basis of our observations, we suggest that the presence of a modified lignin structure could greatly influence cellulose preservation/biodegradability. (Author)

A cosmopolitan late Ediacaran biotic assemblage: new fossils from Nevada and Namibia support a global biostratigraphic link

Science.gov (United States)

Smith, E. F.; Nelson, L. L.; Tweedt, S. M.; Zeng, H.; Workman, Jeremiah B.

2017-01-01

Owing to the lack of temporally well-constrained Ediacaran fossil localities containing overlapping biotic assemblages, it has remained uncertain if the latest Ediacaran (ca 550–541 Ma) assemblages reflect systematic biological turnover or environmental, taphonomic or biogeographic biases. Here, we report new latest Ediacaran fossil discoveries from the lower member of the Wood Canyon Formation in Nye County, Nevada, including the first figured reports of erniettomorphs, Gaojiashania, Conotubus and other problematic fossils. The fossils are spectacularly preserved in three taphonomic windows and occur in greater than 11 stratigraphic horizons, all of which are below the first appearance of Treptichnus pedum and the nadir of a large negative δ13C excursion that is a chemostratigraphic marker of the Ediacaran–Cambrian boundary. The co-occurrence of morphologically diverse tubular fossils and erniettomorphs in Nevada provides a biostratigraphic link among latest Ediacaran fossil localities globally. Integrated with a new report of Gaojiashania from Namibia, previous fossil reports and existing age constraints, these finds demonstrate a distinctive late Ediacaran fossil assemblage comprising at least two groups of macroscopic organisms with dissimilar body plans that ecologically and temporally overlapped for at least 6 Myr at the close of the Ediacaran Period. This cosmopolitan biotic assemblage disappeared from the fossil record at the end of the Ediacaran Period, prior to the Cambrian radiation.

The first fossil of a bolbitidoid fern belongs to the early-divergent lineages of Elaphoglossum (Dryopteridaceae).

Science.gov (United States)

Lóriga, Josmaily; Schmidt, Alexander R; Moran, Robbin C; Feldberg, Kathrin; Schneider, Harald; Heinrichs, Jochen

2014-09-01

• Closing gaps in the fossil record and elucidating phylogenetic relationships of mostly incomplete fossils are major challenges in the reconstruction of the diversification of fern lineages through time. The cosmopolitan family Dryopteridaceae represents one of the most species-rich families of leptosporangiate ferns, yet its fossil record is sparse and poorly understood. Here, we describe a fern inclusion in Miocene Dominican amber and investigate its relationships to extant Dryopteridaceae.• The morphology of the fossil was compared with descriptions of extant ferns, resulting in it being tentatively assigned to the bolbitidoid fern genus Elaphoglossum. This assignment was confirmed by reconstructing the evolution of the morphological characters preserved in the inclusion on a molecular phylogeny of 158 extant bolbitidoid ferns. To assess the morphology-based assignment of the fossil to Elaphoglossum, we examined DNA-calibrated divergence time estimates against the age of the amber deposits from which it came.• The fossil belongs to Elaphoglossum and is the first of a bolbitidoid fern. Its assignment to a particular section of Elaphoglossum could not be determined; however, sects. Lepidoglossa, Polytrichia, and Setosa can be discounted because the fossil lacks subulate scales or scales with acicular marginal hairs. Thus, the fossil might belong to either sects. Amygdalifolia, Wrightiana, Elaphoglossum, or Squamipedia or to an extinct lineage.• The discovery of a Miocene Elaphoglossum fossil provides remarkable support to current molecular clock-based estimates of the diversification of these ferns. © 2014 Botanical Society of America, Inc.

Mummified fossil woods of Fagaceae from the upper Oligocene of Guangxi, South China

Science.gov (United States)

Huang, Luliang; Jin, Jianhua; Quan, Cheng; Oskolski, Alexei A.

2018-02-01

Three new fossil species, two attributed to the genus Castanopsis (C. nanningensis and C. guangxiensis) and one to the organ genus Lithocarpoxylon (L. nanningensis) are described on the basis of well-preserved mummified wood from the upper Oligocene of Yongning Formation in the Nanning Basin, Guangxi Province, South China. The two species of Castanopsis represent the most ancient reliable wood record of this genus in China and also southeastern Asia, which is the center of diversity of extant species. The fossil leaf records of Castanopsis indicated this genus has migrated to South China in the late Eocene. This fossil wood evidence confirms the presence and persistence of Castanopsis in this region in the late Oligocene. In the Yongning Formation, the presence of numerous Fagaceae woods with faint or absent growth ring boundaries (in C. nanningensis) occasionally associated with prominent ring-porous patterns, suggests that Guangxi (South China) had a seasonal (probably monsoonal) tropical climate during the late Oligocene.

Unique growth strategy in the Earth's first trees revealed in silicified fossil trunks from China.

Science.gov (United States)

Xu, Hong-He; Berry, Christopher M; Stein, William E; Wang, Yi; Tang, Peng; Fu, Qiang

2017-11-07

Cladoxylopsida included the earliest large trees that formed critical components of globally transformative pioneering forest ecosystems in the Mid- and early Late Devonian (ca. 393-372 Ma). Well-known cladoxylopsid fossils include the up to ∼1-m-diameter sandstone casts known as Eospermatopteris from Middle Devonian strata of New York State. Cladoxylopsid trunk structure comprised a more-or-less distinct cylinder of numerous separate cauline xylem strands connected internally with a network of medullary xylem strands and, near the base, externally with downward-growing roots, all embedded within parenchyma. However, the means by which this complex vascular system was able to grow to a large diameter is unknown. We demonstrate-based on exceptional, up to ∼70-cm-diameter silicified fossil trunks with extensive preservation of cellular anatomy from the early Late Devonian (Frasnian, ca. 374 Ma) of Xinjiang, China-that trunk expansion is associated with a cylindrical zone of diffuse secondary growth within ground and cortical parenchyma and with production of a large amount of wood containing both rays and growth increments concentrically around individual xylem strands by normal cambia. The xylem system accommodates expansion by tearing of individual strand interconnections during secondary development. This mode of growth seems indeterminate, capable of producing trees of large size and, despite some unique features, invites comparison with secondary development in some living monocots. Understanding the structure and growth of cladoxylopsids informs analysis of canopy competition within early forests with the potential to drive global processes. Published under the PNAS license.

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...

The Fossil Episode

OpenAIRE

John Hassler; Hans-Werner Sinn

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...

Uranium concentration in fossils

International Nuclear Information System (INIS)

Okano, J.; Uyeda, C.

1988-01-01

Recently it is known that fossil bones tend to accumulate uranium. The uranium concentration, C u in fossils has been measured so far by γ ray spectroscopy or by fission track method. The authors applied secondary ion mass spectrometry, SIMS, to detect the uranium in fossil samples. The purpose of this work is to investigate the possibility of semi-quantitative analyses of uranium in fossils, and to study the correlation between C u and the age of fossil bones. The further purpose of this work is to apply SIMS to measure the distribution of C u in fossil teeth

Tracing Biosignature Preservation of Geothermally Silicified Microbial Textures into the Geological Record.

Science.gov (United States)

Campbell, Kathleen A; Lynne, Bridget Y; Handley, Kim M; Jordan, Sacha; Farmer, Jack D; Guido, Diego M; Foucher, Frédéric; Turner, Susan; Perry, Randall S

2015-10-01

New Zealand and Argentine (Late Jurassic-Recent) siliceous hot-spring deposits (sinter) reveal preservation pathways of environmentally controlled, microbe-dominated sedimentary facies over geological time scales. Texturally distinctive, laminated to thinly layered, dense and vertically oriented, microtubular "palisade" fabric is common in low-temperature (geological events. A systematic approach was used to characterize palisade fabric in sinters of different ages to refine tools for recognizing biosignatures in extreme environments and to track their long-term preservation pathways into the geological record. Molecular techniques, scanning electron microscopy, Raman spectrometry, X-ray powder diffraction, petrography, and lipid biomarker analyses were applied. Results indicate that microbial communities vary at the micron scale and that early and rapid silicification is paramount to long-term preservation, especially where minimal postdepositional disturbance follows fossilization. Overall, it appears that the most robust biomarkers of fossil microbial activity in hot-spring deposits are their characteristic macro- and microtextures and laser micro-Raman identified carbon. Studies of Phanerozoic geothermal deposits with mineralized microbial components are relevant analogs for Precambrian geobiology because early life is commonly preserved as microbial microfossils and biofilms in silica, some of it hydrothermal in origin. Yet the diagenetic "movie" has already been run. Hence, studying younger sinters of a range of ages provides an opportunity to "play it again" and follow the varied influences on biosignatures into the deep-time geological record.

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.

Consequences of elevated temperature and pCO 2 on insect folivory at the ecosystem level: perspectives from the fossil record

OpenAIRE

Currano, Ellen D.; Laker, Rachel; Flynn, Andrew G.; Fogt, Kari K.; Stradtman, Hillary; Wing, Scott L.

2016-01-01

Abstract Paleoecological studies document the net effects of atmospheric and climate change in a natural laboratory over timescales not accessible to laboratory or ecological studies. Insect feeding damage is visible on well?preserved fossil leaves, and changes in leaf damage through time can be compared to environmental changes. We measured percent leaf area damaged on four fossil leaf assemblages from the Bighorn Basin, Wyoming, that range in age from 56.1 to 52.65?million years (Ma). We al...

A new interpretation of the bee fossil Melitta willardi Cockerell (Hymenoptera, Melittidae) based on geometric morphometrics of the wing.

Science.gov (United States)

Dewulf, Alexandre; De Meulemeester, Thibaut; Dehon, Manuel; Engel, Michael S; Michez, Denis

2014-01-01

Although bees are one of the major lineages of pollinators and are today quite diverse, few well-preserved fossils are available from which to establish the tempo of their diversification/extinction since the Early Cretaceous. Here we present a reassessment of the taxonomic affinities of Melitta willardiCockerell 1909, preserved as a compression fossil from the Florissant shales of Colorado, USA. Based on geometric morphometric wing shape analyses M. willardi cannot be confidently assigned to the genus Melitta Kirby (Anthophila, Melittidae). Instead, the species exhibits phenotypic affinity with the subfamily Andreninae (Anthophila, Andrenidae), but does not appear to belong to any of the known genera therein. Accordingly, we describe a new genus, Andrenopteryx gen. n., based on wing shape as well as additional morphological features and to accommodate M. willardi. The new combination Andrenopteryx willardi (Cockerell) is established.

A new interpretation of the bee fossil Melitta willardi Cockerell (Hymenoptera, Melittidae based on geometric morphometrics of the wing

Directory of Open Access Journals (Sweden)

Alexandre Dewulf

2014-03-01

Full Text Available Although bees are one of the major lineages of pollinators and are today quite diverse, few well-preserved fossils are available from which to establish the tempo of their diversification/extinction since the Early Cretaceous. Here we present a reassessment of the taxonomic affinities of Melitta willardi Cockerell 1909, preserved as a compression fossil from the Florissant shales of Colorado, USA. Based on geometric morphometric wing shape analyses M. willardi cannot be confidently assigned to the genus Melitta Kirby (Anthophila, Melittidae. Instead, the species exhibits phenotypic affinity with the subfamily Andreninae (Anthophila, Andrenidae, but does not appear to belong to any of the known genera therein. Accordingly, we describe a new genus, Andrenopteryx gen. n., based on wing shape as well as additional morphological features and to accommodate M. willardi. The new combination Andrenopteryx willardi (Cockerell is established.

Spatiotemporal patterns of the fossil-fuel CO2 signal in central Europe: results from a high-resolution atmospheric transport model

Science.gov (United States)

Liu, Yu; Gruber, Nicolas; Brunner, Dominik

2017-11-01

The emission of CO2 from the burning of fossil fuel is a prime determinant of variations in atmospheric CO2. Here, we simulate this fossil-fuel signal together with the natural and background components with a regional high-resolution atmospheric transport model for central and southern Europe considering separately the emissions from different sectors and countries on the basis of emission inventories and hourly emission time functions. The simulated variations in atmospheric CO2 agree very well with observation-based estimates, although the observed variance is slightly underestimated, particularly for the fossil-fuel component. Despite relatively rapid atmospheric mixing, the simulated fossil-fuel signal reveals distinct annual mean structures deep into the troposphere, reflecting the spatially dense aggregation of most emissions. The fossil-fuel signal accounts for more than half of the total (fossil fuel + biospheric + background) temporal variations in atmospheric CO2 in most areas of northern and western central Europe, with the largest variations occurring on diurnal timescales owing to the combination of diurnal variations in emissions and atmospheric mixing and transport out of the surface layer. The covariance of the fossil-fuel emissions and atmospheric transport on diurnal timescales leads to a diurnal fossil-fuel rectifier effect of up to 9 ppm compared to a case with time-constant emissions. The spatial pattern of CO2 from the different sectors largely reflects the distribution and relative magnitude of the corresponding emissions, with power plant emissions leaving the most distinguished mark. An exception is southern and western Europe, where the emissions from the transportation sector dominate the fossil-fuel signal. Most of the fossil-fuel CO2 remains within the country responsible for the emission, although in smaller countries up to 80 % of the fossil-fuel signal can come from abroad. A fossil-fuel emission reduction of 30 % is clearly

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

Livers, guts and gills: mapping the decay profiles of soft tissues to understand authigenic mineral replacement.

Science.gov (United States)

Clements, Thomas; Purnell, Mark; Gabbott, Sarah

2016-04-01

The hard mineralised parts of organisms such as shells, teeth and bones dominate the fossil record. There are, however, sites around the world where soft-tissues are preserved often through rapid replacement of original tissue by rapidly-precipitating authigenic minerals. These exceptionally well-preserved soft-bodied fossils are much more informative about the anatomy, physiology, ecology and behaviour of ancient organisms as well as providing a more inclusive picture of ecosystems and evolution throughout geological time. However, despite the wealth of information that soft-bodied fossils can provide they must first be correctly interpreted as the processes of both decay and preservation act to modify the carcass from its in vivo condition. Decay leads to alteration of the appearance and topology of anatomy, and ultimately to loss. Preservation is selective with some anatomical features being more likely to be captured than others. These problems are especially germane to the interpretation of deep-time and/or enigmatic fossils where no modern analogue exist for comparative anatomical analysis. It is therefore of vital importance to understand the processes carcasses undergo during the fossilisation process, , in order to interpret the anatomical remains of fossils and thus extract true evolutionary presence or absence of anatomy from absence due to taphonomic biases. We have designed a series of novel experiments to investigate, in real time, how decay processes affect the fossilisation potential of soft-tissues - especially of internal anatomy. Our data allow us to unravel both the timing and sequence of anatomical decay of different organs. At the same time through measuring Eh and pH in selected organs we can predict when anatomical features will fall in to the window of authigenic mineralization and thus potentially become preserved. We can also place constraints on which minerals will operate to capture tissues. Our findings are applied to the fossil record

New methods reveal oldest known fossil epiphyllous moss: Bryiidites utahensis gen. et sp. nov. (Bryidae).

Science.gov (United States)

Barclay, Richard S; McElwain, Jennifer C; Duckett, Jeffrey G; van Es, Maarten H; Mostaert, Anika S; Pressel, Silvia; Sageman, Bradley B

2013-12-01

Epiphyllous bryophytes are a highly characteristic feature of many humid tropical forest ecosystems. In contrast to the extensive fossil record for the leaves of their host plants, the record is virtually nonexistent for the epiphylls themselves, despite a fossil record for mosses that begins in the Middle Carboniferous Period, 330 million years ago. Epifluorescence optical microscopy, scanning electron microscopy, and atomic force microscopy were employed to investigate an intimate association between a newly discovered epiphyllous moss and a Lauraceae plant host from the middle Cretaceous. We describe the oldest fossil specimen of an epiphyllous moss, Bryiidites utahensis gen. et sp. nov., identified from an individual specimen only 450 µm long, situated on an approximately one millimeter square fossil leaf fragment. The moss epiphyll is exquisitely preserved as germinating spores and short-celled protonemata with transverse and oblique cross-walls closely matching those of extant epiphyllous mosses on the surface of the plant-leaf hosts. The extension of the epiphyll record back to the middle Cretaceous provides fossil evidence for the appearance of epiphyllous mosses during the diversification of flowering plants, at least 95 million years ago. It also provides substantive evidence for a tropical maritime climate in central North America during the middle Cretaceous.

Insights into the diagenetic environment of fossil marine vertebrates of the Pisco Formation (late Miocene, Peru) from mineralogical and Sr-isotope data

Science.gov (United States)

Gioncada, A.; Petrini, R.; Bosio, G.; Gariboldi, K.; Collareta, A.; Malinverno, E.; Bonaccorsi, E.; Di Celma, C.; Pasero, M.; Urbina, M.; Bianucci, G.

2018-01-01

The late Miocene Pisco Formation of Peru is an outstanding example of richness and high-quality preservation of fossil marine vertebrates. In order to reconstruct the fossilization path, we present new textural, mineralogical and Sr-isotope data of diagenetic minerals formed in correspondence of fossil specimens such as marine vertebrates and mollusks. These fossil specimens were found at Cerro los Quesos, in the Ica Desert, within the diatomaceous strata of the Pisco Formation. Dolomite, gypsum, anhydrite and Mn minerals are the main phases found, while the calcium carbonate originally forming the mollusk valves is replaced by gypsum. An early formation of dolomite and of Mn minerals, triggered by the modifications of the geochemical environment due to organic matter degradation, is suggested by the textural relationships and is confirmed by the Sr isotopic ratio of dolomite, which agrees with that of seawater at the time of sedimentation. Instead, gypsum Sr isotopic ratios indicate a pre-Miocene seawater-derived brine circulating within the sedimentary sequence as a source for Sr. Oxidation of diagenetic sulfide causing a lowering of the pH of porewater is proposed as an explanation for Ca-carbonate dissolution. The diagenetic chemical environment was, nevertheless, favorable to bone preservation.

Preservation of Reduced Carbon on Mars: Implications for Understanding Habitability

Science.gov (United States)

Conrad, Pamela; Fogel, Marilyn; Steele, Andrew; Summons, Roger E.

2007-01-01

Upcoming Mars missions (e.g., Mars Science Laboratory, ExoMars, Astrobiology Field Laboratory, and Mars Sample Return) will search for evidence of extant and fossil microbial habitats and the potential for future habitation. Understanding the distribution and composition of reduced carbon (or organic carbon) is critical for unraveling the Martian carbon cycle, potential for life, and possible biosignature record. Reduced carbon may be produced from biological, geochemical, or interstellar processes; however, evidence for reduced carbon on Mars is lacking with the exception of parts per billion of atmospheric methane. In contrast, abundant atmospheric carbon dioxide may reflect surface oxidation of reduced carbon and accumulation over geological timescales. This suggests that there is an undetected or lost pool of reduced carbon - a pool that may host molecular biosignatures, a characteristic of extant or extinct habitability. In this presentation, we will evaluate factors influencing the preservation potential for organic molecules in rocks on Earth and Martian. We,draw examples from organic molecules in sulfates, basalts, and ancient shales from Mars-analog settings to show how the distribution of organics and their structural patterns will aid Mars habitability studies.

Shotgun microbial profiling of fossil remains

DEFF Research Database (Denmark)

Der Sarkissian, Clio; Ermini, Luca; Jónsson, Hákon

2014-01-01

the specimen of interest, but instead reflect environmental organisms that colonized the specimen after death. Here, we characterize the microbial diversity recovered from seven c. 200- to 13 000-year-old horse bones collected from northern Siberia. We use a robust, taxonomy-based assignment approach...... to identify the microorganisms present in ancient DNA extracts and quantify their relative abundance. Our results suggest that molecular preservation niches exist within ancient samples that can potentially be used to characterize the environments from which the remains are recovered. In addition, microbial...... community profiling of the seven specimens revealed site-specific environmental signatures. These microbial communities appear to comprise mainly organisms that colonized the fossils recently. Our approach significantly extends the amount of useful data that can be recovered from ancient specimens using...

X-ray tomography as a non-destructive tool for evaluating the preservation of primary isotope signatures and mineralogy of Mesozoic fossils

Science.gov (United States)

Santillan, J. D.; Boyce, J. W.; Eagle, R.; Martin, T.; Tuetken, T.; Eiler, J.

2010-12-01

The stable isotope compositions of carbonate and phosphate components in fossil teeth and bone are widely used to infer information on paleoclimate and the physiology of extinct organisms. Recently the potential for measuring the body temperatures of extinct vertebrates from analyses of 13C-18O bond ordering in fossil teeth has been demonstrated (Eagle et al. 2010). The interpretation of these isotopic signatures relies on an assessment of the resistance of fossil bioapatite to alteration, as diffusion within, and partial recrystallization, or replacement of the original bioapatite will lead to measured compositions that represent mixtures between primary and secondary phases and/or otherwise inaccurate apparent temperatures. X-ray computed tomography (CT) allows 3-D density maps of teeth to be made at micron-scale resolution. Such density maps have the potential to record textural evidence for alteration, recrystallization, or replacement of enamel. Because it is non-destructive, CT can be used prior to stable isotope analysis to identify potentially problematic samples without consuming or damaging scientifically significant specimens. As a test, we have applied CT to tooth fragments containing both dentin and enamel from Late Jurassic sauropods and a Late Cretaceous theropod that yielded a range of clumped isotope temperatures from anomalously high ˜60oC to physiologically plausible ≤40oC. This range of temperatures suggests partial, high-temperature modification of some specimens, but possible preservation of primary signals in others. Three-dimensional CT volumes generated using General Electric Phoenix|x-ray CT instruments were compared with visible light and back-scattered electron images of the same samples. The tube-detector combination used for the CT study consisted of a 180 kV nanofocus transmission tube coupled with a 127 micron pixel pitch detector ( ˜3-12μ m voxel edges), allowing us to clearly map out alteration zones in high contrast, while

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.

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…

WHERE ARE THE FOSSILS OF THE FIRST GALAXIES? I. LOCAL VOLUME MAPS AND PROPERTIES OF THE UNDETECTED DWARFS

International Nuclear Information System (INIS)

Bovill, Mia S.; Ricotti, Massimo

2011-01-01

We present a new method for generating initial conditions for ΛCDM N-body simulations which provides the dynamical range necessary to follow the evolution and distribution of the fossils of the first galaxies on Local Volume, 5-10 Mpc, scales. The initial distribution of particles represents the position, velocity, and mass distribution of the dark and luminous halos extracted from pre-reionization simulations. We confirm previous results that ultra-faint dwarfs have properties compatible with being well-preserved fossils of the first galaxies. However, because the brightest pre-reionization dwarfs form preferentially in biased regions, they most likely merge into non-fossil halos with circular velocities >20-30 km s -1 . Hence, we find that the maximum luminosity of true fossils in the Milky Way is L V 6 L sun , casting doubts on the interpretation that some classical dSphs are true fossils. In addition, we argue that most ultra-faints at small galactocentric distance, R V ) 50 (∼400 kpc) up to 1 Mpc from the Milky Way contains about a hundred true fossils of the first galaxies with V-band luminosity 10 3 -10 5 L sun and half-light radii, r hl ∼ 100-1000 pc.

The Postcranial Skeleton of an Exceptionally Complete Individual of the Plated Dinosaur Stegosaurus stenops (Dinosauria: Thyreophora from the Upper Jurassic Morrison Formation of Wyoming, U.S.A.

Directory of Open Access Journals (Sweden)

Susannah Catherine Rose Maidment

Full Text Available Although Stegosaurus is one of the most iconic dinosaurs, well-preserved fossils are rare and as a consequence there is still much that remains unknown about the taxon. A new, exceptionally complete individual affords the opportunity to describe the anatomy of Stegosaurus in detail for the first time in over a century, and enables additional comparisons with other stegosaurian dinosaurs. The new specimen is from the Red Canyon Ranch Quarry, near Shell Wyoming, and appears to have been so well preserved because it was buried rapidly in a pond or body of standing water immediately after death. The quarry is probably located in the middle part of the Morrison Formation, which is believed to be Tithonian in age in this area. The specimen is referable to Stegosaurus stenops based on the possession of an edentulous anterior portion of the dentary and elevated postzygapophyses on the cervical vertebrae. New information provided by the specimen concerns the morphology of the vertebrae, the iliosacral block and dermal armor. Several aspects of its morphology indicate the individual was not fully skeletally mature at the time of death, corroborating a previous histological study.

The Postcranial Skeleton of an Exceptionally Complete Individual of the Plated Dinosaur Stegosaurus stenops (Dinosauria: Thyreophora) from the Upper Jurassic Morrison Formation of Wyoming, U.S.A.

Science.gov (United States)

Maidment, Susannah Catherine Rose; Brassey, Charlotte; Barrett, Paul Michael

2015-01-01

Although Stegosaurus is one of the most iconic dinosaurs, well-preserved fossils are rare and as a consequence there is still much that remains unknown about the taxon. A new, exceptionally complete individual affords the opportunity to describe the anatomy of Stegosaurus in detail for the first time in over a century, and enables additional comparisons with other stegosaurian dinosaurs. The new specimen is from the Red Canyon Ranch Quarry, near Shell Wyoming, and appears to have been so well preserved because it was buried rapidly in a pond or body of standing water immediately after death. The quarry is probably located in the middle part of the Morrison Formation, which is believed to be Tithonian in age in this area. The specimen is referable to Stegosaurus stenops based on the possession of an edentulous anterior portion of the dentary and elevated postzygapophyses on the cervical vertebrae. New information provided by the specimen concerns the morphology of the vertebrae, the iliosacral block and dermal armor. Several aspects of its morphology indicate the individual was not fully skeletally mature at the time of death, corroborating a previous histological study.

Alectorioid Morphologies in Paleogene Lichens: New Evidence and Re-Evaluation of the Fossil Alectoria succini Mägdefrau

Science.gov (United States)

Kaasalainen, Ulla; Heinrichs, Jochen; Krings, Michael; Myllys, Leena; Grabenhorst, Heinrich; Rikkinen, Jouko; Schmidt, Alexander R.

2015-01-01

One of the most important issues in molecular dating studies concerns the incorporation of reliable fossil taxa into the phylogenies reconstructed from DNA sequence variation in extant taxa. Lichens are symbiotic associations between fungi and algae and/or cyanobacteria. Several lichen fossils have been used as minimum age constraints in recent studies concerning the diversification of the Ascomycota. Recent evolutionary studies of Lecanoromycetes, an almost exclusively lichen-forming class in the Ascomycota, have utilized the Eocene amber inclusion Alectoria succinic as a minimum age constraint. However, a re-investigation of the type material revealed that this inclusion in fact represents poorly preserved plant remains, most probably of a root. Consequently, this fossil cannot be used as evidence of the presence of the genus Alectoria (Parmeliaceae, Lecanorales) or any other lichens in the Paleogene. However, newly discovered inclusions from Paleogene Baltic and Bitterfeld amber verify that alectorioid morphologies in lichens were in existence by the Paleogene. The new fossils represent either a lineage within the alectorioid group or belong to the genus Oropogon. PMID:26053106

Paleovegetation changes recorded by n-alkyl lipids bound in macromolecules of plant fossils and kerogens from the Cretaceous sediments in Japan

Science.gov (United States)

Miyata, Y.; Sawada, K.; Nakamura, H.; Takashima, R.; Takahashi, M.

2014-12-01

Resistant macromolecules composing living plant tissues tend to be preserved through degradation and diagenesis, hence constituate major parts of sedimentary plant-derived organic matter (kerogen), and their monomer compositions vary widely among different plant taxa, organs and growth stages. Thus, analysis of such macromolecule may serve as new technique for paleobotanical evaluation distinctive from classical paleobotnical studies depends on morphological preservation of fossils. In the present study, we analyzed plant fossils and kerogens in sediments from the Cretaceous strata in Japan to examine chemotaxonomic characteristics of fossil macromolecules and to reconstruct paleovegetation change by kerogen analysis. The kerogens were separated from the powdered sediments of Cretaceous Yezo Group, Hokkaido, Japan. All kerogens have been confirmed to be mostly originated from land plant tissues by microscopic observation. Mummified angiosperm and gymnosperm fossil leaves were separated from carbonaceous sandstone of the Cretaceous Ashizawa Formation, Futaba Group. The kerogens and plant fossils were extracted with methanol and dichloromethane, and were subsequently refluxed under 110°C to remove free compounds completely. The residues are hydrolyzed by KOH/methanol under 110°C. These released compounds are analyzed by GC-MS. As main hydrolyzed products (ester-bound molecular units) from all kerogens, C10-C28 n-alkanoic acids and C10-C30 n-alkanols were detected. Recent studies on the hydrolysis products of plant tissues suggested the long chain (>C20) n-alkanols were predominantly abundant in deciduous broadleaved angiosperms. Correspondingly, the stratigraphic variation of the ratios of long chain (>C20) n-alkanols to fatty acids was concordant with the variation of angiosperm/gymnosperm ratios recorded by land plant-derived terpenoid biomarkers. In addition, we found that the long chain n-alkanols/fatty acids ratio in the angiosperm fossil leaf was

Fossil bird eggs from the Pliocene of Laetoli, Tanzania: Their taxonomic and paleoecological relationships

Science.gov (United States)

Harrison, Terry

2005-04-01

Recent paleontological investigations at the Pliocene site of Laetoli and at neighboring localities on the Eyasi Plateau of northern Tanzania have led to the recovery of a sizable collection of fossil bird eggs. The material comes from the Upper Laetolil Beds, dated at ˜3.6-3.8 Ma, and the Lower Laetolil Beds, dated at 3.8 Ma to older than 4.3 Ma. The preservation of relatively complete eggs (other than those of ratites) is an extremely rare occurrence in the fossil record, and Laetoli is the only locality in Africa that has produced such well-preserved eggs. Deposition of carbonatite air-fall tuffs led to the rapid burial of the eggs sub-aerially, and they were then preserved in paleosols that were geochemically conducive to their preservation. The collection of fossil eggs from Laetoli can be assigned to at least five different species of ground-nesting birds, including two or three species of francolins, a species of guineafowl, and a larger bird of uncertain taxonomic status about the size of a bustard. Most of the eggs can be assigned to a large species of Francolinus, similar in size to the extant F. afer and F. leucoscepus. A smaller species of francolin, about the size of Francolinus coqui or F. sephaena, is also represented, but is less common. A single egg may represent an even smaller species of francolin, about the size of Francolinus lathami or F. nahani, but its attribution to Francolinus is less certain. The evidence of at least two species of Francolinus at Laetoli indicates that francolins were already taxonomically diverse in East Africa by the mid-Pliocene. Three eggs are similar in their overall dimensions and morphology to the living Numida meleagris, the helmeted guineafowl. An avian community including at least one small species of francolin, a larger francolin, and a guineafowl (as well as ostriches and a vulture) implies that the paleoecology at Laetoli was likely to have been open woodland, bushland, savanna or grassland. However

Scale insect larvae preserved in vertebrate coprolites (Le Quesnoy, France, Lower Eocene): paleoecological insights.

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Robin, Ninon; Foldi, Imre; Godinot, Marc; Petit, Gilles

2016-10-01

Coprolites of terrestrial vertebrates from the Sparnacian Le Quesnoy locality (Ypresian, Eocene, MP7, 53 Ma; Oise, France) were examined for possible parasitic helminth eggs. The extraction of the coprolite components was performed by a weak acetolyse and a slide mounting in glycerin. This long examination did not reveal paleoparasite remains, which may be explained through several arguments. However, some pollen grains, some enigmatic components, and two well-preserved first-instar cochineal nymphs (Hemiptera: Sternorrhyncha: Coccoidea) were evidenced in coprolites. Identified as Coccidae, these larvae are the earliest stage of the scale insect development ever reported as fossil, revealing the specific environment of preservation that fossilized scats may provide. These observations, combined to the coprolites morphotype, enable to ascribe the fossil scats producer to a small herbivorous mammal present in the deposit (early perissodactyls or Plesiadapidae). Regarding the ecology of extant representatives of Coccidae, this mammal was a likely foliage consumer, and the abundant Juglandaceae and/or Tiliaceae from Le Quesnoy might have lived parasitized by scale insects. These Early Eocene parasites had an already well-established dissemination strategy, with prevalent minute first-instar larvae. The herein performed extraction technique appears well-suited for the study of carbonate coprolites and could certainly be useful for evidencing other kind of microorganisms (including internal parasites).

RX J1548.9+0851, a fossil cluster?

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Eigenthaler, P.; Zeilinger, W. W.

2012-04-01

Context. Fossil galaxy groups are spatially extended X-ray sources with X-ray luminosities above L{X, bol ≥ 1042 h50-2} erg s-1 and a central elliptical galaxy dominating the optical, the second-brightest galaxy being at least 2 mag fainter in the R band. Whether these systems are a distinct class of objects resulting from exceptional formation and evolution histories is still unclear, mainly due to the small number of objects studied so far, mostly lacking spectroscopy of group members for group membership confirmation and a detailed kinematical analysis. Aims: To complement the scarce sample of spectroscopically studied fossils down to their faint galaxy populations, the fossil candidate RX J1548.9+0851 (z = 0.072) is studied in this work. Our results are compared with existing data from fossils in the literature. Methods: We use ESO VLT VIMOS multi-object spectroscopy to determine redshifts of the faint galaxy population and study the luminosity-weighted dynamics and luminosity function of the system. The full-spectrum fitting package ULySS is used to determine ages and metallicities of group members. VIMOS imaging data are used to study the morphology of the central elliptical. Results: We identify 40 group members spectroscopically within the central 300 kpc of the system and find 31 additional redshifts from the literature, resulting in a total number of 54 spectroscopically confirmed group members within 1 Mpc. RX J1548.9+0851 is made up of two bright ellipticals in the central region with a magnitude gap of Δm1,2 = 1.34 in the SDSS r' band leaving the definition of RX J1548.9+0851 being a fossil to the assumption of the virial radius. We find a luminosity-weighted velocity dispersion of 568 km s-1 and a mass of 2.5 × 1014 M⊙ for the system confirming previous studies that revealed fossils to be massive. An average mass-to-light ratio of M/L 400 M⊙/L⊙ is derived from the SDSS g', r', and i' bands. The central elliptical is well-fitted by a pure de

Surface modifications of the Sima de los Huesos fossil humans.

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Andrews, P; Fernandez Jalvo, Y

1997-01-01

The sample of fossil human bones from the Sima de los Huesos, Atapuerca, has been analysed to trace parts of its taphonomic history. The work reported here is restricted to analysis of the skeletal elements preserved and their surface modifications. Preliminary plans of specimen distribution published 6 years ago indicate that the skeletal elements are dispersed within the cave, but more recent data are not yet available. Most of the fossils are broken, with some breakage when the bone was fresh and some when already partly mineralized, both types showing some rounding. There are few longitudinal breaks on shafts of long bones and so very few bone splinters. All skeletal elements are preserved but in unequal proportions, with elements like femora, humeri and mandibles and teeth with greater structural density being best represented. There is no evidence of weathering or of human damage such as cut marks on any of the human assemblage, but trampling damage is present on most bones. Carnivore damage is also common, with some present on more than half the sample, but it is mostly superficial, either on the surfaces of shafts and articular ends or on the edges of spiral breaks. The sizes and distribution of the carnivore pits indicate extensive canid activity, and this is interpreted as scavenging of the bones in place in the cave. Indications of tooth marks from a larger carnivore indicate the activity possibly of a large felid: the marks are too large to be produced by small canids, with the larger marks concentrated on spiral breaks on the more robust bones, and there is no evidence of bone crushing and splintering in the manner of hyaenas. The nature of the SH human assemblage is also consistent with accumulation by humans, the evidence for this being the lack of other animals, especially the lack of herbivorous animals, associated with the humans, and the high number of individuals preserved.

Synchrotron μ-XRF determination of element distribution in fossilized sauropod bones

International Nuclear Information System (INIS)

Zoeger, N.; Wobrauschek, P.; Streli, C.; Jokubonis, C.; Pepponi, G.; FalKEXnberg, G.; Sander, P.M.; Ferreyro, R.; Pyzalla, A.R.

2005-01-01

Full text: Sauropod dinosaurs were typically one magnitude larger than any other living or extinct terrestrial animal. This sheer size of the sauropod leads to scale effects in their biology and physiology that still are only inadequately understood. The primary remnants of the sauropods are their fossilized bones. These fossilized bones have sustained burial for some hundred million years and thus may have experienced significant diagenetic changes which are not affecting bone preservation at the histological level, but lead to significant alterations of the bone microstructure at the sub histological level. We investigated the influence of diagenesis on the microstructure of fossilized sauropod bones using bone cross sections of Brachiosaurus brancai and Barosaurus africanus long bones (femura and humeri) that were excavated from the Tendaguru beds in Tanzania. The change in chemical composition due to interactions between bone and sediments was characterized by synchrotron micro-X-ray fluorescence analysis (SR l'-XRF) in confocal geometry. Measurements have been carried out at the micro-focus end-station at HASYLAB beamline L using a monochromatic synchrotron beam from a bending magnet at 17.2 KEXV. The high spatial resolution achievable using this variant of SR l'-XRF revealed two-dimensional element maps of U, Sr, Pb, Fe, Cu, Mn, V, Cr, Co in the fluorapatite of the fossilized bone and in the calcite filling of the bone cavities. The results show distinct differences in the spatial distribution of these elements. The inhomogeneities of the element distribution observed in the dinosaur bone thus give some indications about the interdiffusion between the bone and its environment. (author)

Synchrotron {mu}-XRF determination of element distribution in fossilized sauropod bones

Energy Technology Data Exchange (ETDEWEB)

Zoeger, N; Wobrauschek, P; Streli, C; Jokubonis, C [TU Wien, Atominstitiut der Oesterreichischen Universitaeten, Stadionallee 2, A-1020 Wien (Austria); Pepponi, G [ITC-irst, Centro per la Ricerca Scientifica e Tecnologica, via Sommarive 18, 38050 Povo, Trento (Italy); FalKEXnberg, G [Hamburger Synchrotronstrahlungslabor HASYLAB am Deutschen Elektronen-Synchrotron, NotKEXstr. 85, 22603 Hamburg (Germany); Sander, P M [Institute for Paleontology, University of Bonn, Nussallee 8, D-53115 Bonn (Germany); Ferreyro, R; Pyzalla, A R [TU Wien, Institute of Material Science and Technology, Karlsplatz 13-308, A-1040 Wien (Austria)

2005-07-01

Full text: Sauropod dinosaurs were typically one magnitude larger than any other living or extinct terrestrial animal. This sheer size of the sauropod leads to scale effects in their biology and physiology that still are only inadequately understood. The primary remnants of the sauropods are their fossilized bones. These fossilized bones have sustained burial for some hundred million years and thus may have experienced significant diagenetic changes which are not affecting bone preservation at the histological level, but lead to significant alterations of the bone microstructure at the sub histological level. We investigated the influence of diagenesis on the microstructure of fossilized sauropod bones using bone cross sections of Brachiosaurus brancai and Barosaurus africanus long bones (femura and humeri) that were excavated from the Tendaguru beds in Tanzania. The change in chemical composition due to interactions between bone and sediments was characterized by synchrotron micro-X-ray fluorescence analysis (SR l'-XRF) in confocal geometry. Measurements have been carried out at the micro-focus end-station at HASYLAB beamline L using a monochromatic synchrotron beam from a bending magnet at 17.2 KEXV. The high spatial resolution achievable using this variant of SR l'-XRF revealed two-dimensional element maps of U, Sr, Pb, Fe, Cu, Mn, V, Cr, Co in the fluorapatite of the fossilized bone and in the calcite filling of the bone cavities. The results show distinct differences in the spatial distribution of these elements. The inhomogeneities of the element distribution observed in the dinosaur bone thus give some indications about the interdiffusion between the bone and its environment. (author)

Investigating the stratigraphy and palaeoenvironments for a suite of newly discovered mid-Cretaceous vertebrate fossil-localities in the Winton Formation, Queensland, Australia

Science.gov (United States)

Tucker, Ryan T.; Roberts, Eric M.; Darlington, Vikie; Salisbury, Steven W.

2017-08-01

The Winton Formation of central Queensland is recognized as a quintessential source of mid-Cretaceous terrestrial faunas and floras in Australia. However, sedimentological investigations linking fossil assemblages and palaeoenvironments across this unit remain limited. The intent of this study was to interpret depositional environments and improve stratigraphic correlations between multiple fossil localities within the preserved Winton Formation in the Eromanga Basin, including Isisford, Lark Quarry, and Bladensburg National Park. Twenty-three facies and six repeated facies associations were documented, indicating a mosaic of marginal marine to inland alluvial depositional environments. These developed synchronously with the final regression of the Eromanga Seaway from central Australia during the late Albian-early Turonian. Investigations of regional- and local-scale structural features and outcrop, core and well analysis were combined with detrital zircon provenance signatures to help correlate stratigraphy and vertebrate faunas across the basin. Significant palaeoenvironmental differences exist between the lower and upper portions of the preserved Winton Formation, warranting informal subdivisions; a lower tidally influenced fluvial-deltaic member and an upper inland alluvial member. This work further demonstrates that the Isisford fauna is part of the lower member of the preserved Winton Formation; whereas, fossil localities around Winton, including Lark Quarry and Bladensburg National Park, are part of the upper member of the Winton Formation. These results permit a more meaningful framework for both regional and global comparisons of the Winton flora and fauna.

First Record of Soft Tissue Preservation in the Upper Devonian of Poland

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Zatoń, Michał; Broda, Krzysztof

2015-01-01

Soft tissue preservation is reported from Upper Devonian deposits of the Holy Cross Mountains, central Poland, for the first time. The preserved soft tissues are muscles associated with arthropod cuticle fragments. The muscles are phosphatized with variable states of preservation. Well-preserved specimens display the typical banding of striated muscles. Other muscle fragments are highly degraded and/or recrystallized such that their microstructure is barely visible. The phosphatized muscles and associated cuticle are fragmented, occur in patches and some are scattered on the bedding plane. Due to the state of preservation and the lack of diagnostic features, the cuticle identification is problematic; however, it may have belonged to a phyllocarid crustacean. Taphonomic features of the remains indicate that they do not represent fossilized fecal matter (coprolite) but may represent a regurgitate, but the hypothesis is difficult to test. Most probably they represent the leftover remains after arthropod or fish scavenging. The present study shows that soft tissues, which even earlier were manipulated by scavenger, may be preserved if only special microenvironmental conditions within and around the animal remains are established. PMID:26559060

El Morro caldera (33° 10‧ S, 66° 24‧ W), San Luis, Argentina: An exceptional case of fossil pre-collapse updoming

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Sruoga, P.; Ibañes, O. D.; Japas, M. S.; Urbina, N. E.

2017-05-01

Volcanism at Sierra del Morro represents the final stages of the flat-slab related magmatism in the easternmost San Luis Neogene Volcanic Belt. This 80 km-long NW-WNW-trending belt tracks the episodic inland migration of both magmatism and tectonic deformation since 18 Ma. The Sierra del Morro stands out in the Eastern Sierras Pampeanas as a metamorphic block uplifted during the Late Miocene-Pleistocene by a combination of magma injection and tectonic deformation. Although sequences that preserve stages of basement updoming are not often preserved, exposures in Sierra del Morro are exception in providing key evidence and insight into the involved processes. Based on the comprehensive study of volcanic stratigraphy and structures, the reconstruction of the volcanic architecture has been carried out. We infer a three stage evolution of the El Morro caldera as follows: 1) pre-collapse updoming and volcanism, 2) collapse caldera formation and 3) post-caldera volcanism. The ascent of magma is recorded in small tumescence sites, strongly controlled by oblique transtensional WNW-NW and ENE-striking brittle-ductile megashear zones. Even though the area affected by tumescence was large, magma injection progressed only locally. At Cerros Guanaco and Pampa, metamorphic rocks were updomed and strongly brecciated, whereas at Sierra del Morro magma was emplaced as pre-collapse domes with associated block-and-ash flows, ignimbrite caldera-forming eruptions and post-caldera lava domes and dykes. The caldera is located in the intersection of two major oblique transtensional WNW-NW and ENE-trending brittle-ductile megashear zones, where the highest positive dilatation occurred.

Regulatory taxation of fossil fuels. Theory and policy

International Nuclear Information System (INIS)

Wolfson, Dirk J.; Koopmans, Carl C.

1996-01-01

Research on energy taxation is often based on purely theoretical deductions. This paper stays closer to the real world, using empirical data and interpreting results in a political-economic setting of risk and uncertainty. Economic growth in developing countries will boost energy demand, increasing the risk of shortages of oil and natural gas half-way through the next century, and of coal towards the year 2100. Furthermore, there is mounting evidence that emissions of CO 2 trigger harmful climate changes. A timely introduction of regulatory taxes will reduce demand for fossil fuels and accelerate the introduction of sustainable technology. The empirical results presented show, moreover, that such taxes may claim a substantial part of the rent on energy extraction for the energy-importing countries. It is argued that optimal control and the avoidance of displacement effects require a tax affecting marginal use, with exceptions to safeguard competitive positions. Exceptions may be scaled down as the jurisdiction is enlarged

Disparities in correlating microstructural to nanostructural preservation of dinosaur femoral bones

Science.gov (United States)

Kim, Jung-Kyun; Kwon, Yong-Eun; Lee, Sang-Gil; Lee, Ji-Hyun; Kim, Jin-Gyu; Huh, Min; Lee, Eunji; Kim, Youn-Joong

2017-03-01

Osteohistological researches on dinosaurs are well documented, but descriptions of direct correlations between the bone microstructure and corresponding nanostructure are currently lacking. By applying correlative microscopy, we aimed to verify that well-preserved osteohistological features correlate with pristine fossil bone nanostructures from the femoral bones of Koreanosaurus boseongensis. The quality of nanostructural preservation was evaluated based on the preferred orientation level of apatite crystals obtained from selected area electron diffraction (SAED) patterns and by measuring the “arcs” from the {100} and {002} diffraction rings. Unlike our expectations, our results revealed that well-preserved microstructures do not guarantee pristine nanostructures and vice versa. Structural preservation of bone from macro- to nanoscale primarily depends on original bioapatite density, and subsequent taphonomical factors such as effects from burial, pressure, influx of external elements and the rate of diagenetic alteration of apatite crystals. Our findings suggest that the efficient application of SAED analysis opens the opportunity for comprehensive nanostructural investigations of bone.

Disc-shaped fossils resembling porpitids or eldonids from the early Cambrian (Series 2: Stage 4 of western USA

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Bruce S. Lieberman

2017-06-01

Full Text Available The morphology and affinities of newly discovered disc-shaped, soft-bodied fossils from the early Cambrian (Series 2: Stage 4, Dyeran Carrara Formation are discussed. These specimens show some similarity to the Ordovician Discophyllum Hall, 1847; traditionally this taxon had been treated as a fossil porpitid. However, recently it has instead been referred to as another clade, the eldonids, which includes the enigmatic Eldonia Walcott, 1911 that was originally described from the Cambrian Burgess Shale. The status of various Proterozoic and Phanerozoic taxa previously referred to porpitids and eldonids is also briefly considered. To help ascertain that the specimens were not dubio- or pseudofossils, elemental mapping using energy dispersive X-ray spectroscopy (EDS was conducted. This, in conjunction with the morphology of the specimens, indicated that the fossils were not hematite, iron sulfide, pyrolusite, or other abiologic mineral precipitates. Instead, their status as biologic structures and thus actual fossils is supported. Enrichment in the element carbon, and also possibly to some extent the elements magnesium and iron, seems to be playing some role in the preservation process.

Fossil evidence for the origin of Homo sapiens.

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Schwartz, Jeffrey H; Tattersall, Ian

2010-01-01

Our species Homo sapiens has never received a satisfactory morphological definition. Deriving partly from Linnaeus's exhortation simply to "know thyself," and partly from the insistence by advocates of the Evolutionary Synthesis in the mid-20th Century that species are constantly transforming ephemera that by definition cannot be pinned down by morphology, this unfortunate situation has led to huge uncertainty over which hominid fossils ought to be included in H. sapiens, and even over which of them should be qualified as "archaic" or as "anatomically modern," a debate that is an oddity in the broader context of paleontology. Here, we propose a suite of features that seems to characterize all H. sapiens alive today, and we review the fossil evidence in light of those features, paying particular attention to the bipartite brow and the "chin" as examples of how, given the continuum from developmentally regulated genes to adult morphology, we might consider features preserved in fossil specimens in a comparative analysis that includes extant taxa. We also suggest that this perspective on the origination of novelty, which has gained a substantial foothold in the general field of evolutionary developmental biology, has an intellectual place in paleoanthropology and hominid systematics, including in defining our species, H. sapiens. Beginning solely with the distinctive living species reveals a startling variety in morphologies among late middle and late Pleistocene hominids, none of which can be plausibly attributed to H. sapiens/H. neanderthalensis admixture. Allowing for a slightly greater envelope of variation than exists today, basic "modern" morphology seems to have appeared significantly earlier in time than the first stirrings of the modern symbolic cognitive system. Copyright © 2010 Wiley-Liss, Inc.

A fossil loricariid catfish (Siluriformes: Loricarioidea from the Taubaté Basin, eastern Brazil

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Maria Claudia Malabarba

Full Text Available A new loricariid catfish is described from the Tremembé Formation (Late Oligocene to Early Miocene sediments of the Taubaté Basin in eastern São Paulo State, Brazil. Taubateia paraiba, new genus and species, is based on a single specimen preserved as a ventral-side impression of an articulated partial neurocranium, dorsal elements of the pectoral girdle and anterior vertebrae. The fossil is identified as belonging to family Loricariidae based on obvious overall similarity and the presence of diagnostic derived characters such as: odontodes, dorsal margin of metapterygoid contacting lateral ethmoid, presence of mesethmoid disk (condyle, and compound pterotic-supracleithrum bone. Also, as in most loricariids, the ossified transcapular (Baudelot's ligament plus basiocciptal lateral process form a prominent transverse wall at the occiput. Other derived characters preserved in Taubateia are synapomorphies at different levels within Loricariidae, including a wide and low parasphenoid, form of pterotic-supracleithrum, shape and position of the mesethmoid disk, a triangular lateral ethmoid with expanded posterolateral corner and a rounded and low ridge articulating with the metapterygoid, and a pointed distal margin of transverse process of the Weberian compound centrum. The derived characters recognized in this fossil are a distinctive combination for diagnosing a new genus and species but not for its unambiguous placements in any of the currently recognized loricariid subfamilies.

Trace Fossil Evidence of Trematode-Bivalve Parasite-Host Interactions in Deep Time.

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Huntley, John Warren; De Baets, Kenneth

2015-01-01

Parasitism is one of the most pervasive phenomena amongst modern eukaryotic life and yet, relative to other biotic interactions, almost nothing is known about its history in deep time. Digenean trematodes (Platyhelminthes) are complex life cycle parasites, which have practically no body fossil record, but induce the growth of characteristic malformations in the shells of their bivalve hosts. These malformations are readily preserved in the fossil record, but, until recently, have largely been overlooked by students of the fossil record. In this review, we present the various malformations induced by trematodes in bivalves, evaluate their distribution through deep time in the phylogenetic and ecological contexts of their bivalve hosts and explore how various taphonomic processes have likely biased our understanding of trematodes in deep time. Trematodes are known to negatively affect their bivalve hosts in a number of ways including castration, modifying growth rates, causing immobilization and, in some cases, altering host behaviour making the host more susceptible to their own predators. Digeneans are expected to be significant agents of natural selection. To that end, we discuss how bivalves may have adapted to their parasites via heterochrony and suggest a practical methodology for testing such hypotheses in deep time. Copyright © 2015 Elsevier Ltd. All rights reserved.

Modeling CO2 emissions from fossil fuel combustion using the logistic equation

International Nuclear Information System (INIS)

Meng, Ming; Niu, Dongxiao

2011-01-01

CO 2 emissions from fossil fuel combustion have been known to contribute to the greenhouse effect. Research on emission trends and further forecasting their further values is important for adjusting energy policies, particularly those relative to low carbon. Except for a few countries, the main figures of CO 2 emission from fossil fuel combustion in other countries are S-shaped curves. The logistic function is selected to simulate the S-shaped curve, and to improve the goodness of fit, three algorithms were provided to estimate its parameters. Considering the different emission characteristics of different industries, the three algorithms estimated the parameters of CO 2 emission in each industry separately. The most suitable parameters for each industry are selected based on the criterion of Mean Absolute Percentage Error (MAPE). With the combined simulation values of the selected models, the estimate of total CO 2 emission from fossil fuel combustion is obtained. The empirical analysis of China shows that our method is better than the linear model in terms of goodness of fit and simulation risk. -- Highlights: → Figures of CO 2 emissions from fossil fuel combustion in most countries are S-shape curves. → Using the logistic function to model the S-shape curve. → Three algorithms are offered to estimate the parameters of the logistic function. → The empirical analysis from China shows that the logistic equation has satisfactory simulation results.

Evidence for opal phytolith preservation in the Langebaanweg ‘E’ Quarry Varswater Formation and its potential for palaeohabitat reconstruction

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P. Haarhof

2010-01-01

Full Text Available At the end of the Miocene epoch, C4 grasslands began to expand at the expense of tree-, shrub- and forb-dominated C3 ecosystems. While C4 grasses were spreading throughout most regions of the world, C3 grasses may have been spreading along South Africa’s southwest coast. Stable isotope analyses of hypsodont fossil ungulates from ‘E’ Quarry, a well-known Late Miocene/Early Pliocene fossil locality near the town of Langebaanweg, suggest that the local environment might have included a substantial C3 grass component. Besides this indirect evidence, little is known about the evolution, nature and importance of grass in the ‘E’ Quarry biome. As a preliminary step towards addressing these questions, we initiated a trial investigation to assess whether sediments at the site are conducive to the preservation of phytoliths, an important tool in the reconstruction of palaeohabitats. Results indicate that fossil phytoliths are sufficiently well preserved to allow a comprehensive analysis of the ‘E’ Quarry phytolith assemblage.

Fossil woods of Detarioideae subfamily (Fabaceae) from El Palmar Formation (Late Pleistocene) in South America

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Ramos, R. Soledad; Brea, Mariana; Kröhling, Daniela M.

2017-11-01

The main aim of the present paper is to describe the first Detarioideae fossil woods from El Palmar Formation (Late Pleistocene) in the Uruguay River Basin (Entre Ríos, Argentina). This study is based on five silicified wood specimens preserved in fluvial deposits, which were transported from their growth site. Two new genera and species are described: Paraoxystigma concordiensis gen. nov and sp. nov. has medium-sized vessels, paratracheal axial parenchyma, heterocellular and multiseriate rays, and diffuse axial canals similar in size and shape to vessels, and Gossweilerodendroxylon palmariensis gen. nov and sp. nov. has medium-sized vessels, alternate intervessel pits, paratracheal and apotracheal axial parenchyma, homocellular and uni to-multiseriate rays, and small diffuse axial canals. These Detarioideae fossil records in south-eastern South America support the existence of a very old relationship with the extant West African forests. Eco-anatomical features observed in these fossil woods, along with the climatic information available from the Nearest Living Relatives (NLRs) comparison, suggest warm and humid climatic conditions for the upper-middle basin of the Uruguay River during some periods of the Late Pleistocene.

Study of metal bioaccumulation by nuclear microprobe analysis of algae fossils and living algae cells

International Nuclear Information System (INIS)

Guo, P.; Wang, J.; Li, X.; Zhu, J.; Reinert, T.; Heitmann, J.; Spemann, D.; Vogt, J.; Flagmeyer, R.-H.; Butz, T.

2000-01-01

Microscopic ion-beam analysis of palaeo-algae fossils and living green algae cells have been performed to study the metal bioaccumulation processes. The algae fossils, both single cellular and multicellular, are from the late Neoproterozonic (570 million years ago) ocean and perfectly preserved within a phosphorite formation. The biosorption of the rare earth element ions Nd 3+ by the green algae species euglena gracilis was investigated with a comparison between the normal cells and immobilized ones. The new Leipzig Nanoprobe, LIPSION, was used to produce a proton beam with 2 μm size and 0.5 nA beam current for this study. PIXE and RBS techniques were used for analysis and imaging. The observation of small metal rich spores (<10 μm) surrounding both of the fossils and the living cells proved the existence of some specific receptor sites which bind metal carrier ligands at the microbic surface. The bioaccumulation efficiency of neodymium by the algae cells was 10 times higher for immobilized algae cells. It confirms the fact that the algae immobilization is an useful technique to improve its metal bioaccumulation

Almost a spider: a 305-million-year-old fossil arachnid and spider origins.

Science.gov (United States)

Garwood, Russell J; Dunlop, Jason A; Selden, Paul A; Spencer, Alan R T; Atwood, Robert C; Vo, Nghia T; Drakopoulos, Michael

2016-03-30

Spiders are an important animal group, with a long history. Details of their origins remain limited, with little knowledge of their stem group, and no insights into the sequence of character acquisition during spider evolution. We describe a new fossil arachnid, Idmonarachne brasierigen. et sp. nov. from the Late Carboniferous (Stephanian,ca 305-299 Ma) of Montceau-les-Mines, France. It is three-dimensionally preserved within a siderite concretion, allowing both laboratory- and synchrotron-based phase-contrast computed tomography reconstruction. The latter is a first for siderite-hosted fossils and has allowed us to investigate fine anatomical details. Although distinctly spider-like in habitus, this remarkable fossil lacks a key diagnostic character of Araneae: spinnerets on the underside of the opisthosoma. It also lacks a flagelliform telson found in the recently recognized, spider-related, Devonian-Permian Uraraneida. Cladistic analysis resolves our new fossil as sister group to the spiders: the spider stem-group comprises the uraraneids and I. brasieri While we are unable to demonstrate the presence of spigots in this fossil, the recovered phylogeny suggests the earliest character to evolve on the spider stem-group is the secretion of silk. This would have been followed by the loss of a flagelliform telson, and then the ability to spin silk using spinnerets. This last innovation defines the true spiders, significantly post-dates the origins of silk, and may be a key to the group's success. The Montceau-les-Mines locality has previously yielded a mesothele spider (with spinnerets). Evidently, Late Palaeozoic spiders lived alongside Palaeozoic arachnid grades which approached the spider condition, but did not express the full suite of crown-group autapomorphies. © 2016 The Authors.

Preservation and reactivation of Candidatus Jettenia asiatica and Anammoxoglobus propionicus using different preservative agents.

Science.gov (United States)

Viancelli, A; Pra, M C; Scussiato, L A; Cantão, M; Ibelli, A M G; Kunz, A

2017-11-01

Anaerobic ammonium oxidation (anammox) bacteria have peculiar characteristics that make them difficult to cultivate. The conservation of these microorganisms in culture collections or laboratories requires successful preservation and reactivation techniques. Furthermore, studies have shown that successful reactivation may be preservative dependent. Considering this, the present study aimed to evaluate the preservation and reactivation of anammox consortia enriched from swine manure treatment lagoons, by using different preservative agents at different temperatures: KNO 3 (at 4 °C), glycerol (-20 °C, -80 °C), and skimmed cow milk (-20 °C, -80 °C, -200 °C). After 4 months, the biomass was thawed (except for KNO 3 ), and the reestablishment of anammox activity was evaluated by stoichiometric coefficients. Microbial community transformation during the reactivation process was also studied by 16S rDNA sequence analysis. The results showed that the anammox biomass preserved with glycerol or skimmed cow milk at -80 °C recovered activity, while the biomass preserved with other methodologies did not reestablish activity during the studied time (90 days). The bacterial community from the biomass with anammox activity was characterized and showed the presence of Candidatus Brocadia anammoxidans, Candidatus Jettenia asiatica, and Candidatus Anammoxoglobus propionicus. Preservation with skimmed cow milk at -80 °C favored the selection of Candidatus Anammoxoglobus propionicus, while preservation with glycerol at -80 °C was successful for Candidatus Jettenia asiatica. The present study was effective on anammox sludge preservation and reactivation using low-cost processes for anammox cultures preservation, which is important for biomass transport and deammonification reactor start up. Copyright © 2017 Elsevier Ltd. All rights reserved.

Morphometric analysis of chameleon fossil fragments from the Early Pliocene of South Africa: a new piece of the chamaeleonid history.

Science.gov (United States)

Dollion, Alexis Y; Cornette, Raphaël; Tolley, Krystal A; Boistel, Renaud; Euriat, Adelaïde; Boller, Elodie; Fernandez, Vincent; Stynder, Deano; Herrel, Anthony

2015-02-01

The evolutionary history of chameleons has been predominantly studied through phylogenetic approaches as the fossil register of chameleons is limited and fragmented. The poor state of preservation of these fossils has moreover led to the origin of numerous nomen dubia, and the identification of many chameleon fossils remains uncertain. We here examine chameleon fossil fragments from the Early Pliocene Varswater formation, exposed at the locality of Langebaanweg "E" Quarry along the southwestern coast of South Africa. Our aim was to explore whether these fossil fragments could be assigned to extant genera. To do so, we used geometric morphometric approaches based on microtomographic imaging of extant chameleons as well as the fossil fragments themselves. Our study suggests that the fossils from this deposit most likely represent at least two different forms that may belong to different genera. Most fragments are phenotypically dissimilar from the South African endemic genus Bradypodion and are more similar to other chameleon genera such as Trioceros or Kinyongia. However, close phenetic similarities between some of the fragments and the Seychelles endemic Archaius or the Madagascan genus Furcifer suggest that some of these fragments may not contain enough genus-specific information to allow correct identification. Other fragments such as the parietal fragments appear to contain more genus-specific information, however. Although our data suggest that the fossil diversity of chameleons in South Africa was potentially greater than it is today, this remains to be verified based on other and more complete fragments.

Status of fossil fuel reserves; Etat des reserves des combustibles fossiles

Energy Technology Data Exchange (ETDEWEB)

Laherrere, J

2005-07-01

Reserves represent the sum of past and future productions up to the end of production. In most countries the reserve data of fields are confidential. Therefore, fossil fuel reserves are badly known because the published data are more political than technical and many countries make a confusion between resources and reserves. The cumulated production of fossil fuels represents only between a third and a fifth of the ultimate reserves. The production peak will take place between 2020 and 2050. In the ultimate reserves, which extrapolate the past, the fossil fuels represent three thirds of the overall energy. This document analyses the uncertainties linked with fossil fuel reserves: reliability of published data, modeling of future production, comparison with other energy sources, energy consumption forecasts, reserves/production ratio, exploitation of non-conventional hydrocarbons (tar sands, extra-heavy oils, bituminous shales, coal gas, gas shales, methane in overpressure aquifers, methane hydrates), technology impacts, prices impact, and reserves growth. (J.S.)

The completeness of the fossil record of plesiosaurs, marine reptiles from the Mesozoic

Directory of Open Access Journals (Sweden)

Samuel L. Tutin

2017-09-01

Full Text Available Plesiosaurs were a highly successful group of marine reptiles occurring worldwide in the Jurassic and Cretaceous, but to date few studies have focused on their preservation through time. Here, we conduct the first detailed assessment of the quality of the plesiosaur fossil record. Data was compiled for 178 specimens representing 114 valid species. For each species we calculated the character completeness metric (CCM: percentage of phylogenetic characters from a cladistic dataset that can be scored for that species and the skeletal completeness metric (SCM: percentage of the overall skeleton that is preserved for that species. Average CCM and SCM values were calculated for individual geological stages. A strong significant positive correlation was recovered between CCM and SCM, suggesting that the two metrics are recording the same signal, at least for this clade. Although a significant correlation between changes in sea level and changes in plesiosaur completeness was not recovered, an underlying negative relationship may be present but obscured by poorly sampled time bins. Plesiosaur completeness though time is not significantly correlated with that for contemporary terrestrial groups (sauropods, pterosaurs, birds, but is significantly correlated with that for ichthyosaurs, suggesting common controls on skeletal preservation in the marine realm. Significantly higher median completeness values in plesiosaurs and ichthyosaurs than in contemporary terrestrial groups support the hypothesis that the marine tetrapod fossil record is more complete than that of terrestrial tetrapods. A collector’s curve for plesiosaurs shows a generally slow constant rate of discovery from the latter part of the 19th century until the 1990s, at which point the rate of discovery increased substantially and shows no sign of slowing. A significant but very weak negative correlation between SCM and the year in which a taxon was named suggests a weak tendency for more

The completeness of the fossil record of plesiosaurs, marine reptiles from the Mesozoic.

Science.gov (United States)

Tutin, Samuel L; Butler, Richard J

2017-01-01

Plesiosaurs were a highly successful group of marine reptiles occurring worldwide in the Jurassic and Cretaceous, but to date few studies have focused on their preservation through time. Here, we conduct the first detailed assessment of the quality of the plesiosaur fossil record. Data was compiled for 178 specimens representing 114 valid species. For each species we calculated the character completeness metric (CCM: percentage of phylogenetic characters from a cladistic dataset that can be scored for that species) and the skeletal completeness metric (SCM: percentage of the overall skeleton that is preserved for that species). Average CCM and SCM values were calculated for individual geological stages. A strong significant positive correlation was recovered between CCM and SCM, suggesting that the two metrics are recording the same signal, at least for this clade. Although a significant correlation between changes in sea level and changes in plesiosaur completeness was not recovered, an underlying negative relationship may be present but obscured by poorly sampled time bins. Plesiosaur completeness though time is not significantly correlated with that for contemporary terrestrial groups (sauropods, pterosaurs, birds), but is significantly correlated with that for ichthyosaurs, suggesting common controls on skeletal preservation in the marine realm. Significantly higher median completeness values in plesiosaurs and ichthyosaurs than in contemporary terrestrial groups support the hypothesis that the marine tetrapod fossil record is more complete than that of terrestrial tetrapods. A collector's curve for plesiosaurs shows a generally slow constant rate of discovery from the latter part of the 19 th century until the 1990s, at which point the rate of discovery increased substantially and shows no sign of slowing. A significant but very weak negative correlation between SCM and the year in which a taxon was named suggests a weak tendency for more recently named

A comparative study of modern and fossil cone scales and seeds of conifers: A geochemical approach

Science.gov (United States)

Artur, Stankiewicz B.; Mastalerz, Maria; Kruge, M.A.; Van Bergen, P. F.; Sadowska, A.

1997-01-01

Modern cone scales and seeds of Pinus strobus and Sequoia sempervirens, and their fossil (Upper Miocene, c. 6 Mar) counterparts Pinus leitzii and Sequoia langsdorfi have been studied using pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS), electron-microprobe and scanning electron microscopy. Microscopic observations revealed only minor microbial activity and high-quality structural preservation of the fossil material. The pyrolysates of both modern genera showed the presence of ligno-cellulose characteristic of conifers. However, the abundance of (alkylated)phenols and 1,2-benzenediols in modern S. sempervirens suggests the presence of non-hydrolysable tannins or abundant polyphenolic moieties not previously reported in modern conifers. The marked differences between the pyrolysis products of both modern genera are suggested to be of chemosystematic significance. The fossil samples also contained ligno-cellulose which exhibited only partial degradation, primarily of the carbohydrate constituents. Comparison between the fossil cone scale and seed pyrolysates indicated that the ligno-cellulose complex present in the seeds is chemically more resistant than that in the cone scales. Principal component analysis (PCA) of the pyrolysis data allowed for the determination of the discriminant functions used to assess the extent of degradation and the chemosystematic differences between both genera and between cone scales and seeds. Elemental composition (C, O, S), obtained using electron-microprobe, corroborated the pyrolysis results. Overall, the combination of chemical, microscopic and statistical methods allowed for a detailed characterization and chemosystematic interpretations of modern and fossil conifer cone scales and seeds.

Children's Ideas about Fossils and Foundational Concepts Related to Fossils

Science.gov (United States)

Borgerding, Lisa A.; Raven, Sara

2018-01-01

Many standards documents and learning progressions recommend evolution learning in elementary grades. Given young children's interest in dinosaurs and other fossils, fossil investigations can provide a rich entry into evolutionary biology for young learners. Educational psychology literature has addressed children's reasoning about foundational…

A Paleocene penguin from New Zealand substantiates multiple origins of gigantism in fossil Sphenisciformes

OpenAIRE

Mayr, Gerald; Scofield, R. Paul; De Pietri, Vanesa L.; Tennyson, Alan J. D.

2017-01-01

One of the notable features of penguin evolution is the occurrence of very large species in the early Cenozoic, whose body size greatly exceeded that of the largest extant penguins. Here we describe a new giant species from the late Paleocene of New Zealand that documents the very early evolution of large body size in penguins. Kumimanu biceae, n. gen. et sp. is larger than all other fossil penguins that have substantial skeletal portions preserved. Several plesiomorphic features place the ne...

The fossil record, function, and possible origins of shell color patterns in Paleozoic marine invertebrates

Energy Technology Data Exchange (ETDEWEB)

Kobluk, D.R. (Univ. of Toronto, Ontario (Canada)); Mapes, R.H. (Ohio Univ., Athens (USA))

1989-02-01

Fossil invertebrate shells and carapaces displaying preserved original color patterns are among the rarest fossils. The fossil record of color patterns extends into the Middle Cambrian where the trilobite Anomocare displays a fan-like array of stripes on the pygidium. About 180 Paleozic genera are known with patterns, including trilobites, cephalopods, gastropods, brachiopods, bivalves, crinoids, and crustaceans. Based upon an analysis of these taxa, it appears that patterns and pigments in middle and late Paleozoic invertebrates may have served several functions such as warning displays, light screening, camouflage, or waste disposal. However, the presence of color patterns in fossil invertebrates in the early Paleozoic may have developed prior to the evolution of vision sufficiently sophisticated to see them. This suggests that camouflage and warning displays were not the original functions of color patterns, and that in the earliest Paleozoic they may not have been functional. The authors propose a hypothesis that involves three developmental phases in the evolution of invertebrate color patterns: (1) the incorporation of metabolic by-products, perhaps some pigmented and some not pigmented, into shells and carapaces as a means of disposal of dietary or metabolic wastes, (2) use of these pigments and patterns as an environmental adaptation, such as light screening, and (3) display during and following the evolution of vision in predators sufficiently sophisticated to see the patterns.

Right-handed fossil humans.

Science.gov (United States)

Lozano, Marina; Estalrrich, Almudena; Bondioli, Luca; Fiore, Ivana; Bermúdez de Castro, José-Maria; Arsuaga, Juan Luis; Carbonell, Eudald; Rosas, Antonio; Frayer, David W

2017-11-01

Fossil hominids often processed material held between their upper and lower teeth. Pulling with one hand and cutting with the other, they occasionally left impact cut marks on the lip (labial) surface of their incisors and canines. From these actions, it possible to determine the dominant hand used. The frequency of these oblique striations in an array of fossil hominins documents the typically modern pattern of 9 right- to 1 left-hander. This ratio among living Homo sapiens differs from that among chimpanzees and bonobos and more distant primate relatives. Together, all studies of living people affirm that dominant right-handedness is a uniquely modern human trait. The same pattern extends deep into our past. Thus far, the majority of inferred right-handed fossils come from Europe, but a single maxilla from a Homo habilis, OH-65, shows a predominance of right oblique scratches, thus extending right-handedness into the early Pleistocene of Africa. Other studies show right-handedness in more recent African, Chinese, and Levantine fossils, but the sample compiled for non-European fossil specimens remains small. Fossil specimens from Sima del los Huesos and a variety of European Neandertal sites are predominately right-handed. We argue the 9:1 handedness ratio in Neandertals and the earlier inhabitants of Europe constitutes evidence for a modern pattern of handedness well before the appearance of modern Homo sapiens. © 2017 Wiley Periodicals, Inc.

Evolution of body size, vision, and biodiversity of coral-associated organisms: evidence from fossil crustaceans in cold-water coral and tropical coral ecosystems.

Science.gov (United States)

Klompmaker, Adiël A; Jakobsen, Sten L; Lauridsen, Bodil W

2016-06-16

Modern cold-water coral and tropical coral environments harbor a highly diverse and ecologically important macrofauna of crustaceans that face elevated extinction risks due to reef decline. The effect of environmental conditions acting on decapod crustaceans comparing these two habitats is poorly understood today and in deep time. Here, we compare the biodiversity, eye socket height as a proxy for eye size, and body size of decapods in fossil cold-water and tropical reefs that formed prior to human disturbance. We show that decapod biodiversity is higher in fossil tropical reefs from The Netherlands, Italy, and Spain compared to that of the exceptionally well-preserved Paleocene (Danian) cold-water reef/mound ecosystem from Faxe (Denmark), where decapod diversity is highest in a more heterogeneous, mixed bryozoan-coral habitat instead of in coral and bryozoan-dominated facies. The relatively low diversity at Faxe was not influenced substantially by the preceding Cretaceous/Paleogene extinction event that is not apparent in the standing diversity of decapods in our analyses, or by sampling, preservation, and/or a latitudinal diversity gradient. Instead, the lower availability of food and fewer hiding places for decapods may explain this low diversity. Furthermore, decapods from Faxe are larger than those from tropical waters for half of the comparisons, which may be caused by a lower number of predators, the delayed maturity, and the increased life span of crustaceans in deeper, colder waters. Finally, deep-water specimens of the benthic crab Caloxanthus from Faxe exhibit a larger eye socket size compared to congeneric specimens from tropical reefs, suggesting that dim light conditions favored the evolution of relatively large eyes. The results suggest a strong habitat control on the biodiversity of crustaceans in coral-associated environments and that the diversity difference between deep, cold-water reefs and tropical reefs evolved at least ~63 million years ago

The Evolution of Reproduction within Testudinata as Evidenced by the Fossil Record

Science.gov (United States)

Lawver, Daniel Ryan

Although known from every continent except Antarctica and having a fossil record ranging from the Middle Jurassic to the Pleistocene, fossil turtle eggs are relatively understudied. In this dissertation I describe four fossil specimens, interpret paleoecology and conduct cladistic analyses in order to investigate the evolution of turtle reproduction. Fossil eggshell descriptions primarily involve analysis by scanning electron and polarized light microscopy, as well as cathodoluminescence to determine the degree of diagenetic alteration. Carapace lengths and gas conductance are estimated in order to investigate the ecology of the adults that produced fossil turtle eggs and clutches, as well as their incubation environments, respectively. Cladistic analyses of turtle egg and reproductive characters permit assessment of the usefulness of these characters for determining phylogenetic relationships of fossil specimens and the evolution of reproduction in turtles. Specimens described here include 1) Testudoolithus oosp. from the Late Cretaceous of Madagascar, 2) a clutch of eggs (some containing late stage embryos and at least one exhibiting multilayer eggshell) from the Late Cretaceous Judith River Formation of Montana and named Testudoolithus zelenitskyae oosp. nov., 3) an egg contained within an adult Basilemys nobilis from the Late Cretaceous Kaiparowits Formation of Utah, and 4) a clutch of Meiolania platyceps eggs from the Pleistocene of Lord Howe Island, Australia. Meiolania platyceps eggs are named Testudoolithus lordhowensis oosp. nov. and provide valuable information on the origin of aragonite eggshell composition and nesting behaviors. Cladistic analyses utilizing egg and reproductive characters are rarely performed on taxa outside of Dinosauria. My analyses demonstrate that morphological data produces poorly resolved trees in which only the clades Adocia and Trionychia are resolved and all other turtles form a large polytomy. However, when combined with

AMERICAN EXCEPTIONALISM

Directory of Open Access Journals (Sweden)

Oana-Andreea Pirnuta

2017-11-01

Full Text Available In an interconnected world where foreign relations matter not only for resources or military alliances but also for cultural relationships, it is highly important to have a better understanding of the power relations among nations. The information carries certain meanings that have important outcomes thus defining the power of a given nation. Foreign policy is the channel through which global politics is exercised. International politics is a hierarchy of power being determined by important cultural, economic as well as geographical aspects. The reasons and strategies that are used in order to reach the outcomes in global politics represent the focus of the present paper. The United States has been the leader in international politics since the early 20th century due to its vast resources and wealth as well as its cultural output. America’s interest in preserving a democratic and free world has its foundation in the beliefs and values it stands for the aim of this paper is to question whether or not there is a concrete premise for the idea of American exceptionalism.

The GB/3D Type Fossils Online Web Portal

Science.gov (United States)

McCormick, T.; Howe, M. P.

2013-12-01

fossils which can be used in education and public outreach. The audience for the web portal includes both professional paleontologists and the general public. The professional paleontologist can use the portal to discover the whereabouts of the type material for a taxon they are studying, and can use the pictures and 3d models to assess the completeness and preservation quality of the material. This may reduce or negate the need to send specimens (which are often fragile and always irreplaceable) to researchers through the post, or for researchers to make possibly long, expensive and environmentally damaging journeys to visit far-off collections. We hope that the pictures and 3d models will help to stimulate public interest in paleontology and natural history. The ability to digitally image and scan specimens in 3d enables institutions to have an archive record in case specimens are lost or destroyed by accident or warfare. Recent events in Cairo and Baghdad remind us that museum collections are vulnerable to civil and military strife.

Comparative taphonomy, taphofacies, and bonebeds of the Mio-Pliocene Purisima Formation, central California: strong physical control on marine vertebrate preservation in shallow marine settings.

Directory of Open Access Journals (Sweden)

Robert W Boessenecker

Full Text Available Taphonomic study of marine vertebrate remains has traditionally focused on single skeletons, lagerstätten, or bonebed genesis with few attempts to document environmental gradients in preservation. As such, establishment of a concrete taphonomic model for shallow marine vertebrate assemblages is lacking. The Neogene Purisima Formation of Northern California, a richly fossiliferous unit recording nearshore to offshore depositional settings, offers a unique opportunity to examine preservational trends across these settings.Lithofacies analysis was conducted to place vertebrate fossils within a hydrodynamic and depositional environmental context. Taphonomic data including abrasion, fragmentation, phosphatization, articulation, polish, and biogenic bone modification were recorded for over 1000 vertebrate fossils of sharks, bony fish, birds, pinnipeds, odontocetes, mysticetes, sirenians, and land mammals. These data were used to compare both preservation of multiple taxa within a single lithofacies and preservation of individual taxa across lithofacies to document environmental gradients in preservation. Differential preservation between taxa indicates strong preservational bias within the Purisima Formation. Varying levels of abrasion, fragmentation, phosphatization, and articulation are strongly correlative with physical processes of sediment transport and sedimentation rate. Preservational characteristics were used to delineate four taphofacies corresponding to inner, middle, and outer shelf settings, and bonebeds. Application of sequence stratigraphic methods shows that bonebeds mark major stratigraphic discontinuities, while packages of rock between discontinuities consistently exhibit onshore-offshore changes in taphofacies.Changes in vertebrate preservation and bonebed character between lithofacies closely correspond to onshore-offshore changes in depositional setting, indicating that the dominant control of preservation is exerted by physical

Comparative taphonomy, taphofacies, and bonebeds of the Mio-Pliocene Purisima Formation, central California: strong physical control on marine vertebrate preservation in shallow marine settings.

Science.gov (United States)

Boessenecker, Robert W; Perry, Frank A; Schmitt, James G

2014-01-01

Taphonomic study of marine vertebrate remains has traditionally focused on single skeletons, lagerstätten, or bonebed genesis with few attempts to document environmental gradients in preservation. As such, establishment of a concrete taphonomic model for shallow marine vertebrate assemblages is lacking. The Neogene Purisima Formation of Northern California, a richly fossiliferous unit recording nearshore to offshore depositional settings, offers a unique opportunity to examine preservational trends across these settings. Lithofacies analysis was conducted to place vertebrate fossils within a hydrodynamic and depositional environmental context. Taphonomic data including abrasion, fragmentation, phosphatization, articulation, polish, and biogenic bone modification were recorded for over 1000 vertebrate fossils of sharks, bony fish, birds, pinnipeds, odontocetes, mysticetes, sirenians, and land mammals. These data were used to compare both preservation of multiple taxa within a single lithofacies and preservation of individual taxa across lithofacies to document environmental gradients in preservation. Differential preservation between taxa indicates strong preservational bias within the Purisima Formation. Varying levels of abrasion, fragmentation, phosphatization, and articulation are strongly correlative with physical processes of sediment transport and sedimentation rate. Preservational characteristics were used to delineate four taphofacies corresponding to inner, middle, and outer shelf settings, and bonebeds. Application of sequence stratigraphic methods shows that bonebeds mark major stratigraphic discontinuities, while packages of rock between discontinuities consistently exhibit onshore-offshore changes in taphofacies. Changes in vertebrate preservation and bonebed character between lithofacies closely correspond to onshore-offshore changes in depositional setting, indicating that the dominant control of preservation is exerted by physical processes. The

Gas in the EU in the Policy of Climate Preservation and Fulfillment of EU Obligations in the Paris Climate Agreement

International Nuclear Information System (INIS)

Bosnjak, R.

2016-01-01

In the last forty years, European energy policies were characterized by efforts toward environment preservation: firstly by reducing harmful gas emissions and secondly by reducing greenhouse gas emissions. The reduction of harmful gases epitomised a renaissance of natural gas consumption as the cleanest fossil fuel. While it was expected that natural gas will, at least in the transitional period up until a complete decarbonization of energy sector, replace consumption of carbon and other fossil fuels with a higher greenhouse gas emission, because of the global economy crisis and because of the change between the ratio of fuel and electrical energy prices, those expectations haven't reached their full potential. This material will present an impact of the climate preservation policies on the expected gas consumption and the possibilities of supplying the European Union with gas in the future.(author).

Cuban strategy for reproducing, preserving and developing nuclear knowledge

International Nuclear Information System (INIS)

Elias Hardy, L.L.; Guzman Martinez, F.; Rodriguez Hoyos, O.E.; Lopez Nunez, A.F.

2006-01-01

One of the problems in the changing world is the preservation of knowledge for the next human generation, and nuclear knowledge is not an exception. Cuba has worked for reproducing, preserving, developing and capturing nuclear knowledge, mainly through a higher education centre, the Higher Institute of Nuclear Sciences and Technologies. This institute is a component of a national network in the preparation of manpower not only for nuclear activities but also for environmental and managerial activities too. (author)

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.

The legacy of fossil fuels

Energy Technology Data Exchange (ETDEWEB)

Armaroli, N.; Balzani, V. [CNR, Bologna (Italy)

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.

Central nervous system and muscular bundles preserved in a 240 million year old giant bristletail (Archaeognatha: Machilidae).

Science.gov (United States)

Montagna, Matteo; Haug, Joachim T; Strada, Laura; Haug, Carolin; Felber, Markus; Tintori, Andrea

2017-04-07

Among the incomparably diverse group of insects no cases of central nervous system (CNS) preservation have been so far described in compression fossils. A third of the fossil insects collected from a 240-239 million year old (Ma) level at Monte San Giorgio UNESCO World Heritage (Switzerland-Italy) underwent phosphatization, resulting in the extraordinary preservation of soft tissues. Here we describe Gigamachilis triassicus gen. et sp. nov. (Archaeognatha: Machiloidea: Machilidae) that, with an estimated total length of ~80 millimeters, represents the largest apterygote insect ever recorded. The holotype preserves: (i) components of the CNS represented by four abdominal ganglia, optic lobes with neuropils and compound retina; (ii) muscular bundles. Moreover, G. triassicus, possessing morphological features that prompt its assignment to the extant archaeognathan ingroup Machilidae, places the origin of modern lineages to Middle Triassic. Interestingly, at Monte San Giorgio, in the same stratigraphic unit the modern morphology of G. triassicus co-occurs with the ancient one represented by Dasyleptus triassicus (Archaeognatha: †Monura). Comparing these two types of body organization we provide a new reconstruction of the possible character evolution leading towards modern archaeognathan forms, suggesting the acquisition of novel features in a lineage of apterygote insects during the Permian or the Lower Triassic.

Sequences, stratigraphy and scenarios: what can we say about the fossil record of the earliest tetrapods?

Science.gov (United States)

Friedman, Matt; Brazeau, Martin D

2011-02-07

Past research on the emergence of digit-bearing tetrapods has led to the widely accepted premise that this important evolutionary event occurred during the Late Devonian. The discovery of convincing digit-bearing tetrapod trackways of early Middle Devonian age in Poland has upset this orthodoxy, indicating that current scenarios which link the timing of the origin of digited tetrapods to specific events in Earth history are likely to be in error. Inspired by this find, we examine the fossil record of early digit-bearing tetrapods and their closest fish-like relatives from a statistical standpoint. We find that the Polish trackways force a substantial reconsideration of the nature of the early tetrapod record when only body fossils are considered. However, the effect is less drastic (and often not statistically significant) when other reliably dated trackways that were previously considered anachronistic are taken into account. Using two approaches, we find that 95 per cent credible and confidence intervals for the origin of digit-bearing tetrapods extend into the Early Devonian and beyond, spanning late Emsian to mid Ludlow. For biologically realistic diversity models, estimated genus-level preservation rates for Devonian digited tetrapods and their relatives range from 0.025 to 0.073 per lineage-million years, an order of magnitude lower than species-level rates for groups typically considered to have dense records. Available fossils of early digited tetrapods and their immediate relatives are adequate for documenting large-scale patterns of character acquisition associated with the origin of terrestriality, but low preservation rates coupled with clear geographical and stratigraphic sampling biases caution against building scenarios for the origin of digits and terrestrialization tied to the provenance of particular specimens or faunas.

The Evolution of Arthropod Body Plans: Integrating Phylogeny, Fossils, and Development-An Introduction to the Symposium.

Science.gov (United States)

Chipman, Ariel D; Erwin, Douglas H

2017-09-01

The last few years have seen a significant increase in the amount of data we have about the evolution of the arthropod body plan. This has come mainly from three separate sources: a new consensus and improved resolution of arthropod phylogeny, based largely on new phylogenomic analyses; a wealth of new early arthropod fossils from a number of Cambrian localities with excellent preservation, as well as a renewed analysis of some older fossils; and developmental data from a range of model and non-model pan-arthropod species that shed light on the developmental origins and homologies of key arthropod traits. However, there has been relatively little synthesis among these different data sources, and the three communities studying them have little overlap. The symposium "The Evolution of Arthropod Body Plans-Integrating Phylogeny, Fossils and Development" brought together leading researchers in these three disciplines and made a significant contribution to the emerging synthesis of arthropod evolution, which will help advance the field and will be useful for years to come. © The Author 2017. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

Uranium concentrations in fossils measured by SIMS

International Nuclear Information System (INIS)

Uyeda, Chiaki; Okano, Jun

1988-01-01

Semiquantitative analyses of uranium in fossil bones and teeth were carried out by SIMS. The results show a tendency that uranium concentrations in the fossils increase with the ages of the fossils. It is noticed that fossil bones and teeth having uranium concentration of more than several hundred ppm are not rare. (author)

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.

Three Cambrian fossils assembled into an extinct body plan of cnidarian affinity.

Science.gov (United States)

Ou, Qiang; Han, Jian; Zhang, Zhifei; Shu, Degan; Sun, Ge; Mayer, Georg

2017-08-15

The early Cambrian problematica Xianguangia sinica , Chengjiangopenna wangii , and Galeaplumosus abilus from the Chengjiang biota (Yunnan, China) have caused much controversy in the past and their phylogenetic placements remain unresolved. Here we show, based on exceptionally preserved material (85 new specimens plus type material), that specimens previously assigned to these three species are in fact parts of the same organism and propose that C. wangii and G. abilus are junior synonyms of X. sinica Our reconstruction of the complete animal reveals an extinct body plan that combines the characteristics of the three described species and is distinct from all known fossil and living taxa. This animal resembled a cnidarian polyp in overall morphology and having a gastric cavity partitioned by septum-like structures. However, it possessed an additional body cavity within its holdfast, an anchoring pit on the basal disk, and feather-like tentacles with densely ciliated pinnules arranged in an alternating pattern, indicating that it was a suspension feeder rather than a predatory actiniarian. Phylogenetic analyses using Bayesian inference and maximum parsimony suggest that X. sinica is a stem-group cnidarian. This relationship implies that the last common ancestor of X. sinica and crown cnidarians was probably a benthic, polypoid animal with a partitioned gastric cavity and a single mouth/anus opening. This extinct body plan suggests that feeding strategies of stem cnidarians may have been drastically different from that of their crown relatives, which are almost exclusively predators, and reveals that the morphological disparity of total-group Cnidaria is greater than previously assumed.

Hominid mandibular corpus shape variation and its utility for recognizing species diversity within fossil Homo.

Science.gov (United States)

Lague, Michael R; Collard, Nicole J; Richmond, Brian G; Wood, Bernard A

2008-12-01

Mandibular corpora are well represented in the hominin fossil record, yet few studies have rigorously assessed the utility of mandibular corpus morphology for species recognition, particularly with respect to the linear dimensions that are most commonly available. In this study, we explored the extent to which commonly preserved mandibular corpus morphology can be used to: (i) discriminate among extant hominid taxa and (ii) support species designations among fossil specimens assigned to the genus Homo. In the first part of the study, discriminant analysis was used to test for significant differences in mandibular corpus shape at different taxonomic levels (genus, species and subspecies) among extant hominid taxa (i.e. Homo, Pan, Gorilla, Pongo). In the second part of the study, we examined shape variation among fossil mandibles assigned to Homo (including H. habilis sensu stricto, H. rudolfensis, early African H. erectus/H. ergaster, late African H. erectus, Asian H. erectus, H. heidelbergensis, H. neanderthalensis and H. sapiens). A novel randomization procedure designed for small samples (and using group 'distinctness values') was used to determine whether shape variation among the fossils is consistent with conventional taxonomy (or alternatively, whether a priori taxonomic groupings are completely random with respect to mandibular morphology). The randomization of 'distinctness values' was also used on the extant samples to assess the ability of the test to recognize known taxa. The discriminant analysis results demonstrated that, even for a relatively modest set of traditional mandibular corpus measurements, we can detect significant differences among extant hominids at the genus and species levels, and, in some cases, also at the subspecies level. Although the randomization of 'distinctness values' test is more conservative than discriminant analysis (based on comparisons with extant specimens), we were able to detect at least four distinct groups among the

Hominid mandibular corpus shape variation and its utility for recognizing species diversity within fossil Homo

Science.gov (United States)

Lague, Michael R; Collard, Nicole J; Richmond, Brian G; Wood, Bernard A

2008-01-01

Mandibular corpora are well represented in the hominin fossil record, yet few studies have rigorously assessed the utility of mandibular corpus morphology for species recognition, particularly with respect to the linear dimensions that are most commonly available. In this study, we explored the extent to which commonly preserved mandibular corpus morphology can be used to: (i) discriminate among extant hominid taxa and (ii) support species designations among fossil specimens assigned to the genus Homo. In the first part of the study, discriminant analysis was used to test for significant differences in mandibular corpus shape at different taxonomic levels (genus, species and subspecies) among extant hominid taxa (i.e. Homo, Pan, Gorilla, Pongo). In the second part of the study, we examined shape variation among fossil mandibles assigned to Homo(including H. habilis sensu stricto, H. rudolfensis, early African H. erectus/H. ergaster, late African H. erectus, Asian H. erectus, H. heidelbergensis, H. neanderthalensis and H. sapiens). A novel randomization procedure designed for small samples (and using group ‘distinctness values’) was used to determine whether shape variation among the fossils is consistent with conventional taxonomy (or alternatively, whether a priori taxonomic groupings are completely random with respect to mandibular morphology). The randomization of ‘distinctness values’ was also used on the extant samples to assess the ability of the test to recognize known taxa. The discriminant analysis results demonstrated that, even for a relatively modest set of traditional mandibular corpus measurements, we can detect significant differences among extant hominids at the genus and species levels, and, in some cases, also at the subspecies level. Although the randomization of ‘distinctness values’ test is more conservative than discriminant analysis (based on comparisons with extant specimens), we were able to detect at least four distinct groups

Eocene Antarctic seasonality inferred from high-resolution stable isotope profiles of fossil bivalves and driftwood

Science.gov (United States)

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

2017-12-01

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

Decay of velvet worms (Onychophora), and bias in the fossil record of lobopodians.

Science.gov (United States)

Murdock, Duncan Je; Gabbott, Sarah E; Mayer, Georg; Purnell, Mark A

2014-11-29

Fossil lobopodians, including animals proposed to have close affinity to modern onychophorans, are crucial to understanding the evolution of the panarthropod body plan and the phylum-level relationships between the ecdysozoan groups. Unfortunately, the key features of their anatomy are un-mineralized and subject to biases introduced during death, decay and preservation, yet the extent to which these fossils have been affected by the processes of post-mortem decay is entirely untested. Recent experimental work on chordates has highlighted a profound bias caused by decay, resulting in the erroneous interpretation of badly decayed specimens as primitive members of a clade (stemward slippage). The degree to which this bias affects organisms other than chordates is unknown. Here we use experimental decay of velvet worms (Onychophora) to examine the importance of decay bias in fossil lobopodians. Although we find stemward slippage is not significant in the interpretation of non-mineralized lobopodian fossils, the affect of decay is far from unbiased. Quantitative analysis reveals significant changes in body proportions during decay, a spectrum of decay resistance across anatomical features, and correlated decay of topologically associated characters. These results have significant implications for the interpretation of fossil lobopodian remains, demonstrating that features such as body outline and relative proportions are unreliable for taxonomy or phylogenetic reconstruction, unless decay is taken into account. Similarly, the non-independent loss of characters, due to juxtaposition in the body, during decay has the potential to bias phylogenetic analyses of non-biomineralized fossils. Our results are difficult to reconcile with interpretations of highly decay-prone tissues and structures, such as neural tissue, and complex musculature, in recently described Cambrian lobopodians. More broadly, we hypothesize that stemward slippage is unlikely to be a significant factor

Fossilized skin reveals coevolution with feathers and metabolism in feathered dinosaurs and early birds.

Science.gov (United States)

McNamara, Maria E; Zhang, Fucheng; Kearns, Stuart L; Orr, Patrick J; Toulouse, André; Foley, Tara; Hone, David W E; Rogers, Chris S; Benton, Michael J; Johnson, Diane; Xu, Xing; Zhou, Zhonghe

2018-05-25

Feathers are remarkable evolutionary innovations that are associated with complex adaptations of the skin in modern birds. Fossilised feathers in non-avian dinosaurs and basal birds provide insights into feather evolution, but how associated integumentary adaptations evolved is unclear. Here we report the discovery of fossil skin, preserved with remarkable nanoscale fidelity, in three non-avian maniraptoran dinosaurs and a basal bird from the Cretaceous Jehol biota (China). The skin comprises patches of desquamating epidermal corneocytes that preserve a cytoskeletal array of helically coiled α-keratin tonofibrils. This structure confirms that basal birds and non-avian dinosaurs shed small epidermal flakes as in modern mammals and birds, but structural differences imply that these Cretaceous taxa had lower body heat production than modern birds. Feathered epidermis acquired many, but not all, anatomically modern attributes close to the base of the Maniraptora by the Middle Jurassic.

Three-dimensional preservation of cellular and subcellular structures suggests 1.6 billion-year-old crown-group red algae

DEFF Research Database (Denmark)

Bengtson, Stefan; Sallstedt, Therese; Belivanova, Veneta

2017-01-01

The ~1.6 Ga Tirohan Dolomite of the Lower Vindhyan in central India contains phosphatized stromatolitic microbialites. We report from there uniquely well-preserved fossils interpreted as probable crown-group rhodophytes (red algae). The filamentous form Rafatazmia chitrakootensis n. gen, n. sp. has....... The wider affinities of Denaricion are uncertain. Ramathallus lobatus n. gen., n. sp. is a lobate sessile alga with pseudoparenchymatous thallus, “cell fountains,” and apical growth, suggesting florideophycean affinity. If these inferences are correct, Rafatazmia and Ramathallus represent crown......-group multicellular rhodophytes, antedating the oldest previously accepted red alga in the fossil record by about 400 million years....

Fossil fuel produced radioactivities and their effect on the food chain (II)

International Nuclear Information System (INIS)

Okamoto, K.

1982-01-01

The effects of radioactivities released from fossil fuel burning are examined. Main radioactivities are 210 Pb and 210 Po. Revised values of the dose due to the intake of leafy vegetables and seafoods are presented. The dose from natural gas from the Northern Sea is shown to be much lower than the dose from coal. This conclusion can probably apply to other natural gas except for that from the North American continent. The dose due to coal burning is found to be much higher than that due to marine disposal of nuclear waste

Fossil fuel produced radioactivities and their effect on the food chain (II)

Energy Technology Data Exchange (ETDEWEB)

Okamoto, K [New South Wales Univ., Kensington (Australia). Dept. of Applied Mathematics

1982-03-01

The effects of radioactivities released from fossil fuel burning are examined. Main radioactivities are /sup 210/Pb and /sup 210/Po. Revised values of the dose due to the intake of leafy vegetables and seafoods are presented. The dose from natural gas from the Northern Sea is shown to be much lower than the dose from coal. This conclusion can probably apply to other natural gas except for that from the North American continent. The dose due to coal burning is found to be much higher than that due to marine disposal of nuclear waste.

Bayesian phylogenetic estimation of fossil ages.

Science.gov (United States)

Drummond, Alexei J; Stadler, Tanja

2016-07-19

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 using

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

Evaluation of fresh and preserved herbaceous field crops for biogas and ethanol production

Energy Technology Data Exchange (ETDEWEB)

Pakarinen, A

2012-07-01

In the future, various forms of bioenergy will be increasingly required to replace fossil energy. Globally, transportation uses almost one third of fossil energy resources, and it is thus of great importance to find ethically, economically, and environmentally viable biofuels in near future. Fieldgrown biomass, including energy crops and crop residues, are alternatives to supplement other non-food biofuel raw materials. The aim of this work was to evaluate the potential of five crops, maize (Zea mays L.), fiber hemp (Cannabis sativa L.), faba bean (Vicia faba L.), white lupin (Lupinus albus L.), and Jerusalem artichoke (Heliantus tuborosus L.) cultivated in boreal conditions as raw materials for methane and ethanol. Climate, cultivation requirements, chemical composition, and recalcitrance are some of the parameters to be considered when choosing energy crops for cultivation and for efficient conversion into biofuels. Among the studied crops, protein-rich legumes (faba bean and white lupin) were attractive options for methane, while hemp and Jerusalem artichoke had high theoretical potential for ethanol. Maize was, however, equally suitable for production of both energy carriers. Preservation of crop materials is essential to preserve and supply biomass material throughout the year. Preservation can be also considered as a mild pretreatment prior to biofuel production. Ensiling was conducted on maize, hemp, and faba bean in this work and additionally hemp was preserved in alkali conditions. Ensiling was found to be most beneficial for hemp when converted to methane, increasing the methane yield by more than 50%, whereas preservation with urea increased the energy yield of hemp as ethanol by 39%. Maize, with a high content of water-soluble carbohydrates (20% of DM), required an acid additive in order to preserve the sugars. Interestingly, hydrothermal pretreatment for maize and hemp prior to methane production was less efficient than ensiling. Enzymatic hydrolysis

CERN Services for Long Term Data Preservation

CERN Document Server

Shiers, Jamie; Blomer, Jakob; Ganis, Gerardo; Dallmeier-Tiessen, Sunje; Simko, Tibor; Cancio Melia, German; CERN. Geneva. IT Department

2016-01-01

In this paper we describe the services that are offered by CERN for Long Term preservation of High Energy Physics (HEP) data, with the Large Hadron Collider (LHC) as a key use case. Data preservation is a strategic goal for European High Energy Physics (HEP), as well as for the HEP community worldwide and we position our work in this global content. Specifically, we target the preservation of the scientific data, together with the software, documentation and computing environment needed to process, (re-)analyse or otherwise (re-)use the data. The target data volumes range from hundreds of petabytes (PB – 10^15 bytes) to hundreds of exabytes (EB – 10^18 bytes) for a target duration of several decades. The Use Cases driving data preservation are presented together with metrics that allow us to measure how close we are to meeting our goals, including the possibility for formal certification for at least part of this work. Almost all of the services that we describe are fully generic – the exception being A...

Anaerobic Cultures from Preserved Tissues of Baby Mammoth

Science.gov (United States)

Pikuta, Elena V.; Hoover, Richard B.; Fisher, Daniel

2011-01-01

Microbiological analysis of several cold-preserved tissue samples from the Siberian baby mammoth known as Lyuba revealed a number of culturable bacterial strains that were grown on anaerobic media at 4 C. Lactic acid produced by LAB (lactic acid bacteria) group, usually by members of the genera Carnobacterium and Lactosphera, appears to be a wonderful preservative that prevents other bacteria from over-dominating a system. Permafrost and lactic acid preserved the body of this one-month old baby mammoth and kept it in exceptionally good condition, resulting in this mammoth being the most complete such specimen ever recovered. The diversity of novel anaerobic isolates was expressed on morphological, physiological and phylogenetic levels. Here we discuss the specifics of the isolation of new strains, differentiation from trivial contamination, and preliminary results for the characterization of cultures.

A review and phylogeny of Scarabaeine dung beetle fossils (Coleoptera: Scarabaeidae: Scarabaeinae, with the description of two Canthochilum species from Dominican amber

Directory of Open Access Journals (Sweden)

Sergei Tarasov

2016-05-01

Full Text Available Despite the increasing rate of systematic research on scarabaeine dung beetles (Coleoptera: Scarabaeidae: Scarabaeinae, their fossil record has remained largely unrevised. In this paper, we review all 33 named scarabaeine fossils and describe two new species from Dominican amber (Canthochilum alleni sp.n., Canthochilum philipsivieorum sp.n.. We provide a catalogue of all fossil Scarabaeinae and evaluate their assignment to this subfamily, based primarily on the original descriptions but also, where possible, by examining the type specimens. We suggest that only 21 fossil taxa can be reliably assigned to the Scarabaeinae, while the remaining 14 should be treated as doubtful Scarabaeinae. The doubtful scarabaeines include the two oldest dung beetle fossils known from the Cretaceous and we suggest excluding them from any assessments of the minimum age of scarabaeine dung beetles. The earliest reliably described scarabaeine fossil appears to be Lobateuchus parisii, known from Oise amber (France, which shifts the minimum age of the Scarabaeinae to the Eocene (53 Ma. We scored the best-preserved fossils, namely Lobateuchus and the two Canthochilum species described herein, into the character matrix used in a recent morphology-based study of dung beetles, and then inferred their phylogenetic relationships with Bayesian and parsimony methods. All analyses yielded consistent phylogenies where the two fossil Canthochilum are placed in a clade with the extant species of Canthochilum, and Lobateuchus is recovered in a clade with the extant genera Ateuchus and Aphengium. Additionally, we evaluated the distribution of dung beetle fossils in the light of current global dung beetle phylogenetic hypotheses, geological time and biogeography. The presence of only extant genera in the late Oligocene and all later records suggests that the main present-day dung beetle lineages had already been established by the late Oligocene–mid Miocene.

Progress in ESR dating of fossils

International Nuclear Information System (INIS)

Ikeya, M.

1983-01-01

In this review the progress of ESR dating is briefly described together with its historical development. Examples of fossil dating include shells and corals in geological sediments, fossil bones and teeth in anthropology and fossil woods in geology. The total dose of natural radiation (TD) equivalent to the archaeological dose in TL dating was obtained by the additive dose method. Initially, the TDs were plotted against the known ages; using the apparent annual dose-rate thus obtained gives the ESR age within a factor of 2 or 3 for a fossil. Precise assessment of the radiation environment was made later taking the disequilibrium of uranium series disintegration into account. ESR ages of corals agreed well with those obtained by radiocarbon and uranium-thorium methods. The time-independent accumulation rate or a linear accumulation or uranium was adopted as a first sensible model for the opensystem fossil bones: the relation between the TD and the age explains the ages of anthropologically important bones. Lastly, geological assessment of fossil woods was made by ESR based on the organic radicals and electron traps in the silicified part. (author)

Miocene Fossils Reveal Ancient Roots for New Zealand's Endemic Mystacina (Chiroptera and Its Rainforest Habitat.

Directory of Open Access Journals (Sweden)

Suzanne J Hand

Full Text Available The New Zealand endemic bat family Mystacinidae comprises just two Recent species referred to a single genus, Mystacina. The family was once more diverse and widespread, with an additional six extinct taxa recorded from Australia and New Zealand. Here, a new mystacinid is described from the early Miocene (19-16 Ma St Bathans Fauna of Central Otago, South Island, New Zealand. It is the first pre-Pleistocene record of the modern genus and it extends the evolutionary history of Mystacina back at least 16 million years. Extant Mystacina species occupy old-growth rainforest and are semi-terrestrial with an exceptionally broad omnivorous diet. The majority of the plants inhabited, pollinated, dispersed or eaten by modern Mystacina were well-established in southern New Zealand in the early Miocene, based on the fossil record from sites at or near where the bat fossils are found. Similarly, many of the arthropod prey of living Mystacina are recorded as fossils in the same area. Although none of the Miocene plant and arthropod species is extant, most are closely related to modern taxa, demonstrating potentially long-standing ecological associations with Mystacina.

First report of bats (Mammalia: Chiroptera from the Gray Fossil Site (late Miocene or early Pliocene, Tennessee, USA

Directory of Open Access Journals (Sweden)

Nicholas J. Czaplewski

2017-04-01

Full Text Available Thousands of vertebrate fossils have been recovered from the Gray Fossil Site, Tennessee, dating to the Miocene-Pliocene boundary. Among these are but eight specimens of bats representing two different taxa referable to the family Vespertilionidae. Comparison of the fossils with Neogene and Quaternary bats reveals that seven of the eight specimens pertain to a species of Eptesicus that cannot be distinguished from recent North American Eptesicus fuscus. The remaining specimen, a horizontal ramus with m3, is from a smaller vespertilionid bat that cannot confidently be assigned to a genus. Although many vespertilionid genera can be excluded through comparisons, and many extinct named taxa cannot be compared due to nonequivalence of preserved skeletal elements, the second taxon shows morphological similarities to small-bodied taxa with three lower premolar alveoli, three distinct m3 talonid cusps, and m3 postcristid showing the myotodont condition. It resembles especially Nycticeius humeralis and small species of Eptesicus. Eptesicus cf. E. fuscus potentially inhabited eastern North America continuously since the late Hemphillian land mammal age, when other evidence from the Gray Fossil Site indicates the presence in the southern Appalachian Mountains of a warm, subtropical, oak-hickory-conifer forest having autochthonous North American as well as allochthonous biogeographical ties to eastern Asia and tropical-subtropical Middle America.

The fossil history of pseudoscorpions (Arachnida: Pseudoscorpiones

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D. Harms

2017-08-01

Full Text Available Pseudoscorpions, given their resemblance to scorpions, have attracted human attention since the time of Aristotle, although they are much smaller and lack the sting and elongated tail. These arachnids have a long evolutionary history but their origins and phylogenetic affinities are still being debated. Here, we summarise their fossil record based on a comprehensive review of the literature and data contained in other sources. Pseudoscorpions are one of the oldest colonisers of the land, with fossils known since the Middle Devonian (ca. 390 Ma. The only arachnid orders with an older fossil record are scorpions, harvestmen and acariform mites, plus two extinct groups. Pseudoscorpions do not fossilise easily, and records from the Mesozoic and Cenozoic consist almost exclusively of amber inclusions. Most Mesozoic fossils come from Archingeay and Burmese ambers (Late Cretaceous and those from the Cenozoic are primarily from Eocene Baltic amber, although additional fossils from, for example, Miocene Dominican and Mexican ambers, are known. Overall, 16 of the 26 families of living pseudoscorpions have been documented from fossils and 49 currently valid species are recognised in the literature. Pseudoscorpions represent a case of morphological stasis and even the Devonian fossils look rather modern. Indeed, most amber fossils are comparable to Recent groups despite a major gap in the fossil record of almost 250 Myr. Baltic amber inclusions indicate palaeofauna inhabiting much warmer climates than today and point to climatic shifts in central Europe since the Eocene. They also indicate that some groups (e.g. Feaellidae and Pseudogarypidae had much wider Eocene distributions. Their present-day occurrence is relictual and highlights past extinction events. Faunas from younger tropical amber deposits (e.g. Dominican and Mexican amber are comparable to Recent ones. Generally, there is a strong bias in the amber record towards groups that live under tree

Evaluation of hard fossil fuel

International Nuclear Information System (INIS)

Zivkovic, S.; Nuic, J.

1999-01-01

Because of its inexhaustible supplies hard fossil fuel will represent the pillar of the power systems of the 21st century. Only high-calorie fossil fuels have the market value and participate in the world trade. Low-calorie fossil fuels ((brown coal and lignite) are fuels spent on the spot and their value is indirectly expressed through manufactured kWh. For the purpose of determining the real value of a tonne of low-calorie coal, the criteria that help in establishing the value of a tonne of hard coal have to be corrected and thus evaluated and assessed at the market. (author)

A new find of the fossil Cyclosorus from the Eocene of South China and its paleoclimatic implication.

Science.gov (United States)

Naugolnykh, Serge V; Wang, Li; Han, Meng; Jin, Jian-Hua

2016-01-01

The thelypteroid ferns are widely distributed across tropical regions around the world, but information about their fossil representatives is scarce. A new species, Cyclosorus scutum Naugolnykh, Wang, Han et Jin was discovered from the Eocene Changchang Formation of Hainan Island, South China, and is described on the basis of sterile and fertile leaves, sori, sporangia and spores preserved in situ. Discovery of this new species clearly shows that climatic conditions of that time in this area were humid, i.e. warm and wet.

Fossil energy use and the environment

International Nuclear Information System (INIS)

Sage, P.W.

1994-01-01

Energy demand projections indicate that fossil energy will provide some ninety per cent of global primary energy demand for the foreseeable future. This paper considers the principal environmental impacts associated with fossil energy use and describes approaches to minimise them. Technologies are now available to reduce significantly pollutant emissions from fossil fuel use. Emerging technologies offer higher conversion efficiencies to reduce still further specific emissions per unit of energy output. It is essential, particularly in those areas of rapid growth in energy use, that best practice and technology are deployed. Technology transfer and training will help to achieve this and enable fossil energy use to be fully compatible with increasingly stringent environmental requirements. (author) 4 figs., 12 refs

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.

Status of fossil fuel reserves

International Nuclear Information System (INIS)

Laherrere, J.

2005-01-01

Reserves represent the sum of past and future productions up to the end of production. In most countries the reserve data of fields are confidential. Therefore, fossil fuel reserves are badly known because the published data are more political than technical and many countries make a confusion between resources and reserves. The cumulated production of fossil fuels represents only between a third and a fifth of the ultimate reserves. The production peak will take place between 2020 and 2050. In the ultimate reserves, which extrapolate the past, the fossil fuels represent three thirds of the overall energy. This document analyses the uncertainties linked with fossil fuel reserves: reliability of published data, modeling of future production, comparison with other energy sources, energy consumption forecasts, reserves/production ratio, exploitation of non-conventional hydrocarbons (tar sands, extra-heavy oils, bituminous shales, coal gas, gas shales, methane in overpressure aquifers, methane hydrates), technology impacts, prices impact, and reserves growth. (J.S.)

New fossil fuel combustion technologies

International Nuclear Information System (INIS)

Minghetti, E.; Palazzi, G.

1995-01-01

The aim of the present article 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 efforts 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 article the international and national energy situations and trends are shown. After some brief notes on environmental problems and alternative fuels, such as bio masses and municipal wastes, technological aspects, mainly relevant to increase fossil-fueled power plant performances, are examined in greater depth. Finally the research and technological development activities of ENEA (Italian Agency for New Technologies, Energy and Environment) Engineering Branch, in order to improve fossil fuels energy and environmental use are presented

Hominin track assemblages from Okote Member deposits near Ileret, Kenya, and their implications for understanding fossil hominin paleobiology at 1.5 Ma.

Science.gov (United States)

Hatala, Kevin G; Roach, Neil T; Ostrofsky, Kelly R; Wunderlich, Roshna E; Dingwall, Heather L; Villmoare, Brian A; Green, David J; Braun, David R; Harris, John W K; Behrensmeyer, Anna K; Richmond, Brian G

2017-11-01

Tracks can provide unique, direct records of behaviors of fossil organisms moving across their landscapes millions of years ago. While track discoveries have been rare in the human fossil record, over the last decade our team has uncovered multiple sediment surfaces within the Okote Member of the Koobi Fora Formation near Ileret, Kenya that contain large assemblages of ∼1.5 Ma fossil hominin tracks. Here, we provide detailed information on the context and nature of each of these discoveries, and we outline the specific data that are preserved on the Ileret hominin track surfaces. We analyze previously unpublished data to refine and expand upon earlier hypotheses regarding implications for hominin anatomy and social behavior. While each of the track surfaces discovered at Ileret preserves a different amount of data that must be handled in particular ways, general patterns are evident. Overall, the analyses presented here support earlier interpretations of the ∼1.5 Ma Ileret track assemblages, providing further evidence of large, human-like body sizes and possibly evidence of a group composition that could support the emergence of certain human-like patterns of social behavior. These data, used in concert with other forms of paleontological and archaeological evidence that are deposited on different temporal scales, offer unique windows through which we can broaden our understanding of the paleobiology of hominins living in East Africa at ∼1.5 Ma. Copyright © 2017 Elsevier Ltd. All rights reserved.

A Late Jurassic fossil assemblage in Gondwana: Biostratigraphy and correlations of the Tacuarembó Formation, Parana Basin, Uruguay

Science.gov (United States)

Perea, Daniel; Soto, Matías; Veroslavsky, Gerardo; Martínez, Sergio; Ubilla, Martín

2009-08-01

The Tacuarembó Formation has yielded a fossil assemblage that includes the best known body fossils, consisting of isolated scales, teeth, spines, and molds of bones, recovered from thin and patchy bonebeds, from the Botucatu Desert, Parana Basin, South America. The remains are preserved in the sandstones widespread around the city of Tacuarembó. We propose a new formalized nomenclature for the Tacuarembó Formation, naming its "Lower" and "Upper" members as the Batoví (new name) and Rivera (new rank) members, respectively. An assemblage zone is defined for the Batoví Member (fluviolacustrine and aeolian deposits). In this unit, the freshwater hybodontid shark Priohybodusarambourgi D'Erasmo is well represented. This species was previously recorded in Late Jurassic-Early Cretaceous units of the Sahara and the southern Arabian Peninsula. Globally considered, the fossil assemblage of this member ( P. arambourgi, dipnoan fishes, Ceratosaurus-like theropods, and conchostracans) is indicative of a Kimmeridgian-Tithonian age, which in combination with the stratigraphic relationships of the Tacuarembó Formation with the overlying basalts of the Arapey Formation (132 My average absolute age) implies that the latter was deposited during the Kimmeridgian-Hauterivian interval.

Melanins in Fossil Animals: Is It Possible to Infer Life History Traits from the Coloration of Extinct Species?

Science.gov (United States)

Negro, Juan J; Finlayson, Clive; Galván, Ismael

2018-01-23

Paleo-colour scientists have recently made the transition from describing melanin-based colouration in fossil specimens to inferring life-history traits of the species involved. Two such cases correspond to counter-shaded dinosaurs: dark-coloured due to melanins dorsally, and light-coloured ventrally. We believe that colour reconstruction of fossils based on the shape of preserved microstructures-the majority of paleo-colour studies involve melanin granules-is not without risks. In addition, animals with contrasting dorso-ventral colouration may be under different selection pressures beyond the need for camouflage, including, for instance, visual communication or ultraviolet (UV) protection. Melanin production is costly, and animals may invest less in areas of the integument where pigments are less needed. In addition, melanocytes exposed to UV radiation produce more melanin than unexposed melanocytes. Pigment economization may thus explain the colour pattern of some counter-shaded animals, including extinct species. Even in well-studied extant species, their diversity of hues and patterns is far from being understood; inferring colours and their functions in species only known from one or few specimens from the fossil record should be exerted with special prudence.

Melanins in Fossil Animals: Is It Possible to Infer Life History Traits from the Coloration of Extinct Species?

Science.gov (United States)

Negro, Juan J.; Finlayson, Clive; Galván, Ismael

2018-01-01

Paleo-colour scientists have recently made the transition from describing melanin-based colouration in fossil specimens to inferring life-history traits of the species involved. Two such cases correspond to counter-shaded dinosaurs: dark-coloured due to melanins dorsally, and light-coloured ventrally. We believe that colour reconstruction of fossils based on the shape of preserved microstructures—the majority of paleo-colour studies involve melanin granules—is not without risks. In addition, animals with contrasting dorso-ventral colouration may be under different selection pressures beyond the need for camouflage, including, for instance, visual communication or ultraviolet (UV) protection. Melanin production is costly, and animals may invest less in areas of the integument where pigments are less needed. In addition, melanocytes exposed to UV radiation produce more melanin than unexposed melanocytes. Pigment economization may thus explain the colour pattern of some counter-shaded animals, including extinct species. Even in well-studied extant species, their diversity of hues and patterns is far from being understood; inferring colours and their functions in species only known from one or few specimens from the fossil record should be exerted with special prudence. PMID:29360744

Melanins in Fossil Animals: Is It Possible to Infer Life History Traits from the Coloration of Extinct Species?

Directory of Open Access Journals (Sweden)

Juan J. Negro

2018-01-01

Full Text Available Paleo-colour scientists have recently made the transition from describing melanin-based colouration in fossil specimens to inferring life-history traits of the species involved. Two such cases correspond to counter-shaded dinosaurs: dark-coloured due to melanins dorsally, and light-coloured ventrally. We believe that colour reconstruction of fossils based on the shape of preserved microstructures—the majority of paleo-colour studies involve melanin granules—is not without risks. In addition, animals with contrasting dorso-ventral colouration may be under different selection pressures beyond the need for camouflage, including, for instance, visual communication or ultraviolet (UV protection. Melanin production is costly, and animals may invest less in areas of the integument where pigments are less needed. In addition, melanocytes exposed to UV radiation produce more melanin than unexposed melanocytes. Pigment economization may thus explain the colour pattern of some counter-shaded animals, including extinct species. Even in well-studied extant species, their diversity of hues and patterns is far from being understood; inferring colours and their functions in species only known from one or few specimens from the fossil record should be exerted with special prudence.

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

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

Uranium in fossil bones

International Nuclear Information System (INIS)

Koul, S.L.

1978-01-01

An attempt has been made to determine the uranium content and thus the age of certain fossil bones Haritalyangarh (Himachal Pradesh), India. The results indicate that bones rich in apatite are also rich in uranium, and that the radioactivity is due to radionuclides in the uranium series. The larger animals apparently have a higher concentration of uranium than the small. The dating of a fossil jaw (elephant) places it in the Pleistocene. (Auth.)

ISCTN: Cuban strategy for reproducing, preserving and developing the nuclear knowledge

International Nuclear Information System (INIS)

Elias Hardy, L.L.; Martinez, F.G.; Rodriguez Hoyos, O.E.; Nunez, A.L.

2004-01-01

One of the problems in the changing world is the preservation of the knowledge for the next human generation and the nuclear knowledge is not an exception. Cuba has worked for reproducing, preserving, developing and capturing the nuclear knowledge, mainly through a higher education center, the Higher Institute of Nuclear Sciences and Technologies. This institute is a component of a national network in the preparation of Manpower not only for nuclear activities and for environmental and managerial too. (author)

Quantifying the impact of µCT-scanning of human fossil teeth on ESR age results.

Science.gov (United States)

Duval, Mathieu; Martín-Francés, Laura

2017-05-01

Fossil human teeth are nowadays systematically CT-scanned by palaeoanthropologists prior to any further analysis. It has been recently demonstrated that this noninvasive technique has, in most cases, virtually no influence on ancient DNA preservation. However, it may have nevertheless an impact on other techniques, like Electron Spin Resonance (ESR) dating, by artificially ageing the apparent age of the sample. To evaluate this impact, we µCT-scanned several modern enamel fragments following the standard analytical procedures employed by the Dental Anthropology Group at CENIEH, Spain, and then performed ESR dose reconstruction for each of them. The results of our experiment demonstrate that the systematic high-resolution µCT-scanning of fossil hominin remains introduces a nonnegligible X-ray dose into the tooth enamel, equivalent to 15-30 Gy depending on the parameters used. This dose may be multiplied by a factor of ∼8 if no metallic filter is used. However, this dose estimate cannot be universally extrapolated to any µCT-scan experiment but has instead to be specifically assessed for each device and set of parameters employed. The impact on the ESR age results is directly dependent on the magnitude of the geological dose measured in fossil enamel but could potentially lead to an age overestimation up to 40% in case of Late Pleistocene samples, if not taken into consideration. © 2017 Wiley Periodicals, Inc.

The Rhynie Chert, Scotland, and the search for life on Mars.

Science.gov (United States)

Preston, Louisa J; Genge, Matthew J

2010-06-01

Knowledge of ancient terrestrial hydrothermal systems-how they preserve biological information and how this information can be detected-is important in unraveling the history of life on Earth and, perhaps, that of extinct life on Mars. The Rhynie Chert in Scotland was originally deposited as siliceous sinter from Early Devonian hot springs and contains exceptionally well-preserved fossils of some of the earliest plants and animals to colonize the land. The aim of this study was to identify biomolecules within the samples through Fourier transform infrared (FTIR) spectroscopy and aid current techniques in identification of ancient hot spring deposits and their biological components on Mars. Floral and faunal fossils within the Rhynie Chert are commonly known; but new, FTIR spectroscopic analyses of these fossils has allowed for identification of biomolecules such as aliphatic hydrocarbons and OH molecules that are potentially derived from the fossilized biota and their environment. Gas chromatograph-mass spectrometer (GCMS) data were used to identify n-alkanes; however, this alone cannot be related to the samples' biota. Silicified microfossils are more resistant to weathering or dissolution, which renders them more readily preservable over time. This is of particular interest in astropaleontological research, considering the similarities in the early evolution of Mars and Earth.

Boron-containing organic pigments from a Jurassic red alga.

Science.gov (United States)

Wolkenstein, Klaus; Gross, Jürgen H; Falk, Heinz

2010-11-09

Organic biomolecules that have retained their basic chemical structures over geological periods (molecular fossils) occur in a wide range of geological samples and provide valuable paleobiological, paleoenvironmental, and geochemical information not attainable from other sources. In rare cases, such compounds are even preserved with their specific functional groups and still occur within the organisms that produced them, providing direct information on the biochemical inventory of extinct organisms and their possible evolutionary relationships. Here we report the discovery of an exceptional group of boron-containing compounds, the borolithochromes, causing the distinct pink coloration of well-preserved specimens of the Jurassic red alga Solenopora jurassica. The borolithochromes are characterized as complicated spiroborates (boric acid esters) with two phenolic moieties as boron ligands, representing a unique class of fossil organic pigments. The chiroptical properties of the pigments unequivocally demonstrate a biogenic origin, at least of their ligands. However, although the borolithochromes originated from a fossil red alga, no analogy with hitherto known present-day red algal pigments was found. The occurrence of the borolithochromes or their possible diagenetic products in the fossil record may provide additional information on the classification and phylogeny of fossil calcareous algae.

Microscopic and immunohistochemical analyses of the claw of the nesting dinosaur, Citipati osmolskae.

Science.gov (United States)

Moyer, Alison E; Zheng, Wenxia; Schweitzer, Mary H

2016-11-16

One of the most well-recognized Cretaceous fossils is Citipati osmolskae (MPC-D 100/979), an oviraptorid dinosaur discovered in brooding position on a nest of unhatched eggs. The original description refers to a thin lens of white material extending from a manus ungual, which was proposed to represent original keratinous claw sheath that, in life, would have covered it. Here, we test the hypothesis that this exceptional morphological preservation extends to the molecular level. The fossil sheath was compared with that of extant birds, revealing similar morphology and microstructural organization. In living birds, the claw sheath consists primarily of two structural proteins; alpha-keratin, expressed in all vertebrates, and beta-keratin, found only in reptiles and birds (sauropsids). We employed antibodies raised against avian feathers, which comprise almost entirely of beta-keratin, to demonstrate that fossil tissues respond with the same specificity, though less intensity, as those from living birds. Furthermore, we show that calcium chelation greatly increased antibody reactivity, suggesting a role for calcium in the preservation of this fossil material. © 2016 The Author(s).

Differential preservation of vertebrates in Southeast Asian caves

Directory of Open Access Journals (Sweden)

Julien Louys

2017-09-01

Full Text Available Caves have been an important source of vertebrate fossils for much of Southeast Asia, particularly for the Quaternary. Despite this importance, the mechanisms by which vertebrate remains accumulate and preserve in Southeast Asian caves has never been systematically reviewed or examined. Here, we present the results of three years of cave surveys in Indonesia and Timor-Leste, describing cave systems and their attendant vertebrate accumulations in diverse geological, biogeographical, and environmental settings. While each cave system is unique, we find that the accumulation and preservation of vertebrate remains are highly dependent on local geology and environment. These factors notwithstanding, we find the dominant factor responsible for faunal deposition is the presence or absence of biological accumulating agents, a factor directly dictated by biogeographical history. In small, isolated, volcanic islands, the only significant accumulation occurs in archaeological settings, thereby limiting our understanding of the palaeontology of those islands prior to human arrival. In karstic landscapes on both oceanic and continental islands, our understanding of the long-term preservation of vertebrates is still in its infancy. The formation processes of vertebrate-bearing breccias, their taphonomic histories, and the criteria used to determine whether these represent syngenetic or multiple deposits remain critically understudied. The latter in particular has important implications for arguments on how breccia deposits from the region should be analysed and interpreted when reconstructing palaeoenvironments.

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

Science.gov (United States)

Ulevicius, Vidmantas; Byčenkienė, Steigvilė; Bozzetti, Carlo; Vlachou, Athanasia; Plauškaitė, Kristina; Mordas, Genrik; Dudoitis, Vadimas; Abbaszade, Gülcin; Remeikis, Vidmantas; Garbaras, Andrius; Masalaite, Agne; Blees, Jan; Fröhlich, Roman; Dällenbach, Kaspar R.; Canonaco, Francesco; Slowik, Jay G.; Dommen, Josef; Zimmermann, Ralf; Schnelle-Kreis, Jürgen; Salazar, Gary A.; Agrios, Konstantinos; Szidat, Sönke; El Haddad, Imad; Prévôt, André S. H.

2016-05-01

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 total carbon (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 7-13 %, respectively. Isotope ratios of stable carbon and nitrogen isotopes were used to distinguish aerosol particles associated with solid and liquid fossil fuel burning.

The first fossil leaf insect: 47 million years of specialized cryptic morphology and behavior.

Science.gov (United States)

Wedmann, Sonja; Bradler, Sven; Rust, Jes

2007-01-09

Stick and leaf insects (insect order Phasmatodea) are represented primarily by twig-imitating slender forms. Only a small percentage ( approximately 1%) of extant phasmids belong to the leaf insects (Phylliinae), which exhibit an extreme form of morphological and behavioral leaf mimicry. Fossils of phasmid insects are extremely rare worldwide. Here we report the first fossil leaf insect, Eophyllium messelensis gen. et sp. nov., from 47-million-year-old deposits at Messel in Germany. The new specimen, a male, is exquisitely preserved and displays the same foliaceous appearance as extant male leaf insects. Clearly, an advanced form of extant angiosperm leaf mimicry had already evolved early in the Eocene. We infer that this trait was combined with a special behavior, catalepsy or "adaptive stillness," enabling Eophyllium to deceive visually oriented predators. Potential predators reported from the Eocene are birds, early primates, and bats. The combination of primitive and derived characters revealed by Eophyllium allows the determination of its exact phylogenetic position and illuminates the evolution of leaf mimicry for this insect group. It provides direct evidence that Phylliinae originated at least 47 Mya. Eophyllium enlarges the known geographical range of Phylliinae, currently restricted to southeast Asia, which is apparently a relict distribution. This fossil leaf insect bears considerable resemblance to extant individuals in size and cryptic morphology, indicating minimal change in 47 million years. This absence of evolutionary change is an outstanding example of morphological and, probably, behavioral stasis.

Fossil Groups as Cosmological Labs

Science.gov (United States)

D'Onghia, Elena

Optical and X-ray measurements of fossil groups (FGs) suggest that they are old and relaxed systems. If FGs are assembled at higher redshift, there is enough time for intermediate-luminosity galaxies to merge, resulting in the formation of the brightest group galaxy (BGG). We carry out the first, systematic study of a large sample of FGs, the "FOssil Group Origins'' (FOGO) based on an International Time Project at the Roque de los Muchachos Observatory. For ten FOGO FGs we have been awarded time at SUZAKU Telescope to measure the temperature of the hot intragroup gas (IGM). For these systems we plan to evaluate and correlate their X-ray luminosity and X-ray temperature, Lx-Tx, optical luminosity and X-ray temperature, Lopt-Tx, and group velocity dispersion with their X-ray temperature, sigma V-Tx, as compared to the non fossil systems. By combining these observations with state-of-art cosmological hydrodynamical simulations we will open a new window into the study of the IGM and the nature of fossil systems. Our proposed work will be of direct relevance for the understanding and interpretation of data from several NASA science missions. Specifically, the scaling relations obtained from these data combined with our predictions obtained using state-of-the-art hydrodynamical simulation numerical adopting a new hydrodynamical scheme will motivate new proposal on CHANDRA X-ray telescope for fossil groups and clusters. We will additionally create a public Online Planetarium Show. This will be an educational site, containing an interactive program called: "A Voyage to our Universe''. In the show we will provide observed images of fossil groups and similar images and movies obtained from the numerical simulations showing their evolution. The online planetarium show will be a useful reference and an interactive educational tool for both students and the public.

On the age of the hominid fossils at the Sima de los Huesos, Sierra de Atapuerca, Spain: paleomagnetic evidence.

Science.gov (United States)

Parés, J M; Pérez-González, A; Weil, A B; Arsuaga, J L

2000-04-01

We report new paleomagnetic data for the Middle Pleistocene hominid-bearing strata in the Sima de los Huesos, North Spain. Sediments (brown muds with human and bear fossils and the underlying sterile clayey and sandy unit) preserve both normal and reversed magnetic components. The sterile unit has exclusively reversed magnetization, dating back to the Matuyama Chron, and thus is Lower Pleistocene in age. The overlying fossiliferous muds have a dominant normal magnetization that overprints a partially resolved reversed magnetization. These data are compatible with one of the reversal events that occurred during the Brunhes Chron. Combined with the existing U-series dates and evidence from the macro- and microfauna, these paleomagnetic results suggest an age of the hominid fossils between 325 to 205 ka, whereas the underlying sand and silts are older than 780 ka. Copyright 2000 Wiley-Liss, Inc.

Fossil and non-fossil sources of organic carbon (OC and elemental carbon (EC in Göteborg, Sweden

Directory of Open Access Journals (Sweden)

S. Szidat

2009-03-01

Full Text Available Particulate matter was collected at an urban site in Göteborg (Sweden in February/March 2005 and in June/July 2006. Additional samples were collected at a rural site for the winter period. Total carbon (TC concentrations were 2.1–3.6 μg m⁻³, 1.8–1.9 μg m⁻³, and 2.2–3.0 μg m⁻³ for urban/winter, rural/winter, and urban/summer conditions, respectively. Elemental carbon (EC, organic carbon (OC, water-insoluble OC (WINSOC, and water-soluble OC (WSOC were analyzed for ¹⁴C in order to distinguish fossil from non-fossil emissions. As wood burning is the single major source of non-fossil EC, its contribution can be quantified directly. For non-fossil OC, the wood-burning fraction was determined independently by levoglucosan and ¹⁴C analysis and combined using Latin-hypercube sampling (LHS. For the winter period, the relative contribution of EC from wood burning to the total EC was >3 times higher at the rural site compared to the urban site, whereas the absolute concentrations of EC from wood burning were elevated only moderately at the rural compared to the urban site. Thus, the urban site is substantially more influenced by fossil EC emissions. For summer, biogenic emissions dominated OC concentrations most likely due to secondary organic aerosol (SOA formation. During both seasons, a more pronounced fossil signal was observed for Göteborg than has previously been reported for Zurich, Switzerland. Analysis of air mass origin using back trajectories suggests that the fossil impact was larger when local sources dominated, whereas long-range transport caused an enhanced non-fossil signal. In comparison to other European locations, concentrations of levoglucosan and other monosaccharide anhydrides were low for the urban and the rural site in the area of Göteborg during winter.

THE GB/3D Fossil Types Online Database

Science.gov (United States)

Howe, M. P.; McCormick, T.

2012-12-01

The ICZN and the International Code of Nomenclature for algae, fungi and plants require that every species or subspecies of organism (living & fossil), should have a type or reference specimen to define its characteristic features. These specimens are held in collections around the world and must be available for study. Over time, type specimens can deteriorate or become lost. The British Geological Survey, the National Museum of Wales, the Sedgwick Museum Cambridge and the Oxford Museum of Natural History are working together to create an online database of the type fossils they hold. The web portal provides data about each specimen, searchable on taxonomic, stratigraphic and spatial criteria. For each specimen it is possible to view and download high resolution photographs, and for many of them, 'anaglyph' stereo pairs and 3D scans are available. The portal also provides educational resources (OERs). The rise to prominence of the Web has transformed expectations in accessing information and the Web is now usually the first port of call. However, while many geological museums are providing web-searchable text catalogues, few have undertaken a large-scale program of providing images and 3D models. This project has tackled the issues of merging four distinct data holdings, and setting up workflows to image and scan large numbers of disparate fossils, ranging from small invertebrate macrofossils to large vertebrate skeletal elements. There are three advantages in providing such resources: (1) All users can exploit the collections more efficiently. End-users can view specimens remotely and assess their nature, preservation quality and completeness - in some cases this may be sufficient. It will reduce the need for institutions to send specimens (which are often fragile and always irreplaceable) to researchers by post, or for researchers to make possibly long, expensive and environmentally damaging journeys. (2) A public outreach and education dividend - the ability to

Eocene fossil is earliest evidence of flower-visiting by birds.

Science.gov (United States)

Mayr, Gerald; Wilde, Volker

2014-05-01

Birds are important pollinators, but the evolutionary history of ornithophily (bird pollination) is poorly known. Here, we report a skeleton of the avian taxon Pumiliornis from the middle Eocene of Messel in Germany with preserved stomach contents containing numerous pollen grains of an eudicotyledonous angiosperm. The skeletal morphology of Pumiliornis is in agreement with this bird having been a, presumably nectarivorous, flower-visitor. It represents the earliest and first direct fossil evidence of flower-visiting by birds and indicates a minimum age of 47 million years for the origin of bird-flower interactions. As Pumiliornis does not belong to any of the modern groups of flower-visiting birds, the origin of ornithophily in some angiosperm lineages may have predated that of their extant avian pollinators. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Environmental costs of fossil fuel energy production

International Nuclear Information System (INIS)

Riva, A.; Trebeschi, C.

1997-01-01

The costs of environmental impacts caused by fossil fuel energy production are external to the energy economy and normally they are not reflected in energy prices. To determine the environmental costs associated with an energy source a detailed analysis of all environmental impacts of the complete energy cycle is required. The economic evaluation of environmental damages is presented caused by atmospheric emissions produced by fossil fuel combustion for different uses. Considering the emission factors of sulphur oxides, nitrogen oxides, dust and carbon dioxide and the economic evaluation of their environmental damages reported in literature, a range of environmental costs associated with different fossil fuels and technologies is presented. A comparison of environmental costs resulting from atmospheric emissions produced by fossil-fuel combustion for energy production shows that natural gas has a significantly higher environmental value than other fossil fuels. (R.P.)

Comparison of 230Th/234U Dating Results Obtained on Fossil Mollusk Shell from Morocco and Fossil Coral Samples from Egypt. Research of Methodological Criteria to Valid the Measured Age

International Nuclear Information System (INIS)

Choukri, A.; Hakam, O.K.; Reyss, J.L.

2013-01-01

Radiochemical ages of 126 unrecrystallized coral samples from the Egyptian shoreline and 125 fossil mollusk shell samples from the Atlantic coast of Moroccan High Atlas are discussed.For corals, the obtained ages are in good agreement with the ages reported previously on urecristallized corals except in some sites where some samples are affected by a cementation of younger aragonite.For mollusk shells, the obtained ages are in the most of cases, rejuvenated.This rejuvenation is due eventually to a post-incorporation of secondary uranium that is responsible of the wide dispersion of apparent ages of mollusk shells.

The rise of fire: Fossil charcoal in late Devonian marine shales as an indicator of expanding terrestrial ecosystems, fire, and atmospheric change

Science.gov (United States)

Rimmer, Susan M.; Hawkins, Sarah J.; Scott, Andrew C.; Cressler, Walter L.

2015-01-01

Fossil charcoal provides direct evidence for fire events that, in turn, have implications for the evolution of both terrestrial ecosystems and the atmosphere. Most of the ancient charcoal record is known from terrestrial or nearshore environments and indicates the earliest occurrences of fire in the Late Silurian. However, despite the rise in available fuel through the Devonian as vascular land plants became larger and trees and forests evolved, charcoal occurrences are very sparse until the Early Mississippian where extensive charcoal suggests well-established fire systems. We present data from the latest Devonian and Early Mississippian of North America from terrestrial and marine rocks indicating that fire became more widespread and significant at this time. This increase may be a function of rising O2 levels and the occurrence of fire itself may have contributed to this rise through positive feedback. Recent atmospheric modeling suggests an O2 low during the Middle Devonian (around 17.5%), with O2 rising steadily through the Late Devonian and Early Mississippian (to 21–22%) that allowed for widespread burning for the first time. In Devonian-Mississippian marine black shales, fossil charcoal (inertinite) steadily increases up-section suggesting the rise of widespread fire systems. There is a concomitant increase in the amount of vitrinite (preserved woody and other plant tissues) that also suggests increased sources of terrestrial organic matter. Even as end Devonian glaciation was experienced, fossil charcoal continued to be a source of organic matter being introduced into the Devonian oceans. Scanning electron and reflectance microscopy of charcoal from Late Devonian terrestrial sites indicate that the fires were moderately hot (typically 500–600 °C) and burnt mainly surface vegetation dominated by herbaceous zygopterid ferns and lycopsids, rather than being produced by forest crown fires. The occurrence and relative abundance of fossil charcoal in

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

2016-05-01

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 total carbon (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 7–13 %, respectively. Isotope ratios of stable carbon and nitrogen isotopes were used to distinguish aerosol particles associated with solid and liquid fossil fuel burning.

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.

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.

Fossil power plant automation

International Nuclear Information System (INIS)

Divakaruni, S.M.; Touchton, G.

1991-01-01

This paper elaborates on issues facing the utilities industry and seeks to address how new computer-based control and automation technologies resulting from recent microprocessor evolution, can improve fossil plant operations and maintenance. This in turn can assist utilities to emerge stronger from the challenges ahead. Many presentations at the first ISA/EPRI co-sponsored conference are targeted towards improving the use of computer and control systems in the fossil and nuclear power plants and we believe this to be the right forum to share our ideas

Progress of fossil fuel science

Energy Technology Data Exchange (ETDEWEB)

Demirbas, M.F.

2007-07-01

Coal is the most abundant and widely distributed fossil fuel. More than 45% of the world's electricity is generated from coal, and it is the major fuel for generating electricity worldwide. The known coal reserves in the world are enough for more than 215 years of consumption, while the known oil reserves are only about 39 times of the world's consumption and the known natural gas reserves are about 63 times of the world's consumption level in 1998. In recent years, there have been effective scientific investigations on Turkish fossil fuels, which are considerable focused on coal resources. Coal is a major fossil fuel source for Turkey. Turkish coal consumption has been stable over the past decade and currently accounts for about 24% of the country's total energy consumption. Lignite coal has had the biggest share in total fossil fuel production, at 43%, in Turkey. Turkish researchers may investigate ten broad pathways of coal species upgrading, such as desulfurization and oxydesulfurization, pyrolysis and hydropyrolysis, liquefaction and hydroliquefaction, extraction and supercritical fluid extraction, gasification, oxidation, briquetting, flotation, and structure identification.

Fossil energy and food security

International Nuclear Information System (INIS)

Folke, G.

2001-01-01

To fulfil the basic goal of delivering food for the tables of the citizens, modern Western agriculture is extremely dependent on supporting material flows, infrastructure, and fossil energy. According to several observers, fossil fuel production is about to peak, i.e., oil extraction is no longer capable of keeping pace with the increasing demand. This situation may trigger an unprecedented increase in fossil energy prices, which may make the current highly energy dependent food production-distribution system highly vulnerable. The paper starts with a survey of this vulnerability. Also, the supply of phosphorus, a key factor in agriculture, may be at stake under such circumstances. The paper analyses this situation and discusses settlement structures integrated with agriculture that might increase food security by reducing energy demands. In the proposed ideal societal structure, agriculture is integrated with settlements and most of the food needed by the population is produced locally, and the nutrients for food production are recycled from households and animals by means of biological processes demanding considerably less mechanical investment and fossil support energy than the conventional type of agriculture. The vulnerability of this structure would be considerably lower, than that of the current system. (author)

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.

2015 Site Environmental Report Fernald Preserve

International Nuclear Information System (INIS)

Hertel, Bill; Hooten, Gwen

2016-01-01

The Fernald Preserve 2015 Site Environmental Report provides stakeholders with the results from the Fernald, Ohio, Site's environmental monitoring programs for 2015; a summary of the U.S. Department of Energy's (DOE's) activities conducted onsite; and a summary of the Fernald Preserve's compliance with the various environmental regulations, compliance agreements, and DOE policies that govern site activities. This report has been prepared in accordance with the ''Integrated Environmental Monitoring Plan,'' which is Attachment D of the Comprehensive Legacy Management and Institutional Controls Plan (LMICP) (DOE 2016). Remediation of the Fernald Preserve has been successfully completed with the exception of the groundwater. During 2015, activities at the Fernald Preserve included: environmental monitoring activities related to direct radiation, groundwater, and surface water; ecological restoration monitoring and maintenance as well as inspections, care, and monitoring of the site and the OSDF to ensure that provisions of the LMICP are fully implemented; OSDF leak detection monitoring and collection, monitoring, and treatment of leachate from the OSDF; extraction, monitoring, and treatment of contaminated groundwater from the Great Miami Aquifer (Operable Unit 5); ongoing operation of the Fernald Preserve Visitors Center, associated outreach, and educational activities; and monitoring as specified in the site's National Pollutant Discharge Elimination System (NPDES) permit. Environmental monitoring programs were developed to ensure that the remedy remains protective of the environment. The requirements of these programs are described in detail in the LMICP and reported in this Site Environmental Report.

Supply of fossil heating and motor fuels

International Nuclear Information System (INIS)

Kaegi, W.; Siegrist, S.; Schaefli, M.; Eichenberger, U.

2003-01-01

This comprehensive study made for the Swiss Federal Office of Energy (SFOE) within the framework of the Energy Economics Fundamentals research programme examines if it can be guaranteed that Swiss industry can be supplied with fossil fuels for heating and transport purposes over the next few decades. The results of a comprehensive survey of literature on the subject are presented, with a major focus being placed on oil. The study examines both pessimistic and optimistic views and also presents an overview of fossil energy carriers and the possibilities of substituting them. Scenarios and prognoses on the availability of fossil fuels and their reserves for the future are presented. Also, new technologies for exploration and the extraction of fossil fuels are discussed, as are international interdependencies that influence supply. Market and price scenarios are presented that take account of a possible increasing scarcity of fossil fuels. The implications for industry and investment planning are examined

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

Directory of Open Access Journals (Sweden)

Jens Lorenz Franzen

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

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

Science.gov (United States)

Franzen, Jens Lorenz; Aurich, Christine; Habersetzer, Jörg

2015-01-01

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

Management of fossil natural resources: the impossible challenge?

International Nuclear Information System (INIS)

Loubens, Audrey

2013-10-01

A set of articles addresses various issues related to fossil energies and resources. A first set addresses the general context of fossil resources: the forced wedding between fossil energies and the environment (discussion of an annual report by the IEA on coal reserves), the availability of fossil fuels (discussion about the high share of fossil fuel in an always more renewable world). A second set addresses how to transform resources into reserves: discussion of the annual IEA report on conventional oil and gas reserves, on unconventional oil and gas reserves, and on coal reserves. The next set is a prospective one, and addresses the question of a scenario by 2040: the extremely high tension between fossil resources and geopolitical reality, and the question of the possibility of a world energy transition (discussions of the World Energy Outlook published by the IEA). Other issues are addressed by the last set of articles: the abundance of fossil energies obscures the potential of renewable energies, the evolution of the chemical industry towards alternative solutions in order to limit the use of hydrocarbons, and the territorial claims by Russia in the Arctic region

Combining phylogenomics and fossils in higher-level squamate reptile phylogeny: molecular data change the placement of fossil taxa.

Science.gov (United States)

Wiens, John J; Kuczynski, Caitlin A; Townsend, Ted; Reeder, Tod W; Mulcahy, Daniel G; Sites, Jack W

2010-12-01

Molecular data offer great potential to resolve the phylogeny of living taxa but can molecular data improve our understanding of relationships of fossil taxa? Simulations suggest that this is possible, but few empirical examples have demonstrated the ability of molecular data to change the placement of fossil taxa. We offer such an example here. We analyze the placement of snakes among squamate reptiles, combining published morphological data (363 characters) and new DNA sequence data (15,794 characters, 22 nuclear loci) for 45 living and 19 fossil taxa. We find several intriguing results. First, some fossil taxa undergo major changes in their phylogenetic position when molecular data are added. Second, most fossil taxa are placed with strong support in the expected clades by the combined data Bayesian analyses, despite each having >98% missing cells and despite recent suggestions that extensive missing data are problematic for Bayesian phylogenetics. Third, morphological data can change the placement of living taxa in combined analyses, even when there is an overwhelming majority of molecular characters. Finally, we find strong but apparently misleading signal in the morphological data, seemingly associated with a burrowing lifestyle in snakes, amphisbaenians, and dibamids. Overall, our results suggest promise for an integrated and comprehensive Tree of Life by combining molecular and morphological data for living and fossil taxa.

Fossil fuel usage and the environment

International Nuclear Information System (INIS)

Klass, D.L.

1991-01-01

The Greenhouse Effect and global warming, ozone formation in the troposphere, ozone destruction in the stratosphere, and acid rain are important environmental issues. The relationship of fossil fuel usage to some of these issues is discussed. Data on fossil fuel consumption and the sources and sinks of carbon dioxide, carbon monoxide, methane, nitrogen and sulfur oxides, and ozone indicate that natural gas provides lower emissions of carbon dioxide, carbon monoxide, and nitrogen and sulfur oxides than other fossil fuels. Global emissions of methane from the gas industry are significantly less than those from other anthropogenic activities and natural sources, and methane plays an important role along with carbon monoxide and nitric oxide in tropospheric ozone formation. Reductions in any or all of these air pollutants would reduce ozone in the lower atmosphere. Several remedial measures have been or are being implemented in certain countries to reduce fossil fuel emissions. These include removal of emissions from the atmosphere by new biomass growth, fuel substitution by use of cleaner burning fuels for stationary and mobile sources, and fossil fuel combustion at higher efficiencies. It is unlikely that concerted environmental action by all governments of the world will occur soon, but much progress has been made to achieve clean air

The advent of animals: The view from the Ediacaran

Science.gov (United States)

Droser, Mary L.; Gehling, James G.

2015-04-01

Patterns of origination and evolution of early complex life on this planet are largely interpreted from the fossils of the Precambrian soft-bodied Ediacara Biota. These fossils occur globally and represent a diverse suite of organisms living in marine environments. Although these exceptionally preserved fossil assemblages are typically difficult to reconcile with modern phyla, examination of the morphology, ecology, and taphonomy of these taxa provides keys to their relationships with modern taxa. Within the more than 30 million y range of the Ediacara Biota, fossils of these multicellular organisms demonstrate the advent of mobility, heterotrophy by multicellular animals, skeletonization, sexual reproduction, and the assembly of complex ecosystems, all of which are attributes of modern animals. This approach to these fossils, without the constraint of attempting phylogenetic reconstructions, provides a mechanism for comparing these taxa with both living and extinct animals.

Primate diversification inferred from phylogenies and fossils.

Science.gov (United States)

Herrera, James P

2017-12-01

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

Using Strong Gravitational Lensing to Identify Fossil Group Progenitors

Science.gov (United States)

Johnson, Lucas E.; Irwin, Jimmy A.; White, Raymond E., III; Wong, Ka-Wah; Maksym, W. Peter; Dupke, Renato A.; Miller, Eric D.; Carrasco, Eleazar R.

2018-04-01

Fossil galaxy systems are classically thought to be the end result of galaxy group/cluster evolution, as galaxies experiencing dynamical friction sink to the center of the group potential and merge into a single, giant elliptical that dominates the rest of the members in both mass and luminosity. Most fossil systems discovered lie within z fossil criteria within the look forward time. Since strong gravitational lensing preferentially selects groups merging along the line of sight, or systems with a high mass concentration like fossil systems, we searched the CASSOWARY survey of strong-lensing events with the goal of determining whether lensing systems have any predisposition to being fossil systems or progenitors. We find that ∼13% of lensing groups are identified as traditional fossils while only ∼3% of nonlensing control groups are. We also find that ∼23% of lensing systems are traditional fossil progenitors compared to ∼17% for the control sample. Our findings show that strong-lensing systems are more likely to be fossil/pre-fossil systems than comparable nonlensing systems. Cumulative galaxy luminosity functions of the lensing and nonlensing groups also indicate a possible, fundamental difference between strong-lensing and nonlensing systems’ galaxy populations, with lensing systems housing a greater number of bright galaxies even in the outskirts of groups.

Developments in fossil fuel electricity generation

International Nuclear Information System (INIS)

Williams, A.; Argiri, M.

1993-01-01

A major part of the world's electricity is generated by the combustion of fossil fuels, and there is a significant environmental impact due to the production of fossil fuels and their combustion. Coal is responsible for 63% of the electricity generated from fossil fuels; natural gas accounts for about 20% and fuel oils for 17%. Because of developments in supply and improvements in generating efficiencies there is apparently a considerable shift towards a greater use of natural gas, and by the year 2000 it could provide 25% of the world electricity output. At the same time the amount of fuel oil burned will have decreased. The means to minimize the environmental impact of the use of fossil fuels, particularly coal, in electricity production are considered, together with the methods of emission control. Cleaner coal technologies, which include fluidized bed combustion and an integrated gasification combined cycle (IGCC), can reduce the emissions of NO x , SO 2 and CO 2 . (author)

OKLO: fossil reactors

International Nuclear Information System (INIS)

Naudet, R.

Events leading up to the discovery during the summer of 1972 of the Oklo fossil reactor in Gabon and its subsequent exploration are reviewed. Results of studies are summarized; future investigations are outlined

Chemosystematics and diagenesis of terpenoids in fossil conifer species and sediment from the Eocene Zeitz formation, Saxony, Germany

Science.gov (United States)

Otto, Angelika; Simoneit, Bernd R. T.

2001-10-01

The biomarker contents of three fossil conifer species (Athrotaxis couttsiae, Taxodium balticum, Pinus palaeostrobus) and the clay sediment from the Eocene Zeitz formation, Germany, have been analyzed by gas chromatography-mass spectrometry. Triterpenoids of the oleanane, ursane and lupane series and aliphatic wax lipids are the major compounds in the total extracts of the sediment indicating a major angiosperm input. In contrast, diterpenoids (abietanes, phenolic abietanes, pimaranes, isopimaranes, kauranes, phyllocladanes, totaranes) and lignin degradation products are predominant in the conifer fossil extracts. Polar diterpenoids (ferruginol and derivatives, dehydroabietic acid) are preserved as major compounds in the conifers, accompained by saturated and aromatic diterpenoid products. The extracts of the fossil conifer species show characteristic biomarker patterns and contain terpenoids of chemosystematic value. The terpenoid composition of the fossil conifers is similar to that of related modern species. Phenolic abietanes (ferruginol, 6,7-dehydroferruginol, hydroxyferruginols, sugiol) which are known from modern species of the Cupressaceae and Podocarpaceae are the major terpenoids in shoots of Athrotaxis couttsiae and a cone of Taxodium balticum (both Cupressaceae). Sesquiterpenoids characteristic for Cupressaceae (cuparene, α-cedrene) are also present in Athrotaxis. Abietane-type acids (dehydroabietic acid, abietic acid) and saturated abietanes [fichtelite, 13α(H)-fichtelite] predominate in the extracts of a Pinus palaeostrobus cone and phenolic abietanes are not detectable. A diagenetic pathway for the degradation of abietic acid is proposed based on the presence of abietane-type acids and a series of their presumed degradation products in the Pinus cone. The formation of diagenetic products from the phenolic abietanes is also discussed.

Taxing fossil fuels under speculative storage

International Nuclear Information System (INIS)

Tumen, Semih; Unalmis, Deren; Unalmis, Ibrahim; Unsal, D. Filiz

2016-01-01

Long-term environmental consequences of taxing fossil fuel usage have been extensively studied in the literature. However, these taxes may also impose several short-run macroeconomic policy challenges, the nature of which remains underexplored. This paper investigates the mechanisms through which environmental taxes on fossil fuel usage can affect the main macroeconomic variables in the short-run. We concentrate on a particular mechanism: speculative storage. Formulating and using a dynamic stochastic general equilibrium (DSGE) model, calibrated for the United States, with an explicit storage facility and nominal rigidities, we show that in designing environmental tax policies it is crucial to account for the fact that fossil fuel prices are subject to speculation. The existence of forward-looking speculators in the model improves the effectiveness of tax policies in reducing fossil fuel usage. Improved policy effectiveness, however, is costly: it drives inflation and interest rates up, while impeding output. Based on this tradeoff, we seek an answer to the question how monetary policy should interact with environmental tax policies in our DSGE model of fossil fuel storage. We show that, in an environment with no speculative storers, monetary policy should respond to output along with CPI inflation in order to minimize the welfare losses brought by taxes. However, when the storage facility is activated, responding to output in the monetary policy rule becomes less desirable.

2015 Site Environmental Report Fernald Preserve

Energy Technology Data Exchange (ETDEWEB)

Hertel, Bill [Navarro Research and Engineering, Oak Ridge, TN (United States); Hooten, Gwen [US Department of Energy, Washington, DC (United States)

2016-05-01

The Fernald Preserve 2015 Site Environmental Report provides stakeholders with the results from the Fernald, Ohio, Site’s environmental monitoring programs for 2015; a summary of the U.S. Department of Energy’s (DOE’s) activities conducted onsite; and a summary of the Fernald Preserve’s compliance with the various environmental regulations, compliance agreements, and DOE policies that govern site activities. This report has been prepared in accordance with the “Integrated Environmental Monitoring Plan,” which is Attachment D of the Comprehensive Legacy Management and Institutional Controls Plan (LMICP) (DOE 2016). Remediation of the Fernald Preserve has been successfully completed with the exception of the groundwater. During 2015, activities at the Fernald Preserve included: environmental monitoring activities related to direct radiation, groundwater, and surface water; ecological restoration monitoring and maintenance as well as inspections, care, and monitoring of the site and the OSDF to ensure that provisions of the LMICP are fully implemented; OSDF leak detection monitoring and collection, monitoring, and treatment of leachate from the OSDF; extraction, monitoring, and treatment of contaminated groundwater from the Great Miami Aquifer (Operable Unit 5); ongoing operation of the Fernald Preserve Visitors Center, associated outreach, and educational activities; and monitoring as specified in the site’s National Pollutant Discharge Elimination System (NPDES) permit. Environmental monitoring programs were developed to ensure that the remedy remains protective of the environment. The requirements of these programs are described in detail in the LMICP and reported in this Site Environmental Report.

Length correction for early-juvenile Brazilian herring Sardinella janeiro (Eigenmann, 1894 after preservation in formalin, ethanol and freezing

Directory of Open Access Journals (Sweden)

Joaquim N. S. Santos

Full Text Available This work aims to quantify the variation in total length and body mass for the early-juvenile Brazilian herring Sardinella janeiro and to determine total length and body mass correction equation to allow fresh measures to be calculated from preserved ones. Fishes were randomly assigned to one of five preservation methods (freezing at - 20º C, 2.5% and 5% formalin, 70% and 95% ethanol, and measured for total length (TL and body mass (W before preservation, and on days 5, 15, 30, and 60 after storage. Significant reductions in total length and body mass occurred during the first 5 days after preservation and continued to contract significantly at a lesser rate through 30 days in most methods. Exceptions were shown for body mass in freezing and 5% formalin, where the greatest losses occurred after 30 days of preservation. The degree of shrinkage for total length and body mass was very much dependent on fish size, with smaller specimens shrinking more than larger ones. The fresh total length and body mass can be back-calculated using equations that describe the relationship between fresh and preserved individuals after 60 days storage for all methods except for body mass in freezing.

First record of lobed trace fossils in Brazil's Upper Cretaceous paleosols: Rhizoliths or evidence of insects and their social behavior?

Science.gov (United States)

Luciano do Nascimento, Diego; Batezelli, Alessandro; Bernardes Ladeira, Francisco Sérgio

2017-11-01

This is the first report of trace fossils potentially associated with insect social behavior in sandy and well-drained paleosols of the Upper Cretaceous continental sequence of Brazil. The trace fossils consist of dozens of lobed and vertical structures cemented by CaCO3 and preserved mainly in full relief in paleosols of the Marilia Formation (Bauru Basin) in the state of Minas Gerais. The described ichnofossils are predominantly vertical, up to 2 m long, and are composed of horizontal lobed structures connected by vertical tunnel-like structures that intersect in the center and at the edges. The lobed structures range from 3 to 15 cm long and 2-6 cm thick. Two different hypotheses are analyzed to explain the origin of the trace fossils; the less probable one is that the structures are laminar calcretes associated with rhizoliths and rhizoconcretions. The hypothesis involving social insects was considered because the trace fossils described herein partially resemble a modern ant nest and the ichnofossil Daimoniobarax. The micromorphological analysis of the lobed and tunnel-like structures indicates modifications of the walls, such as the presence of inorganic fluidized linings, dark linings and oriented grains, supporting the hypothesis that they are chambers and shafts. The architecture and size of the reported nests suggest the possibility that social insect colonies existed during the Maastrichtian and are direct evidence of the social behavior and reproductive strategies of the Cretaceous pedofauna.

Divergence time estimates of mammals from molecular clocks and fossils: relevance of new fossil finds from India.

Science.gov (United States)

Prasad, G V R

2009-11-01

This paper presents a brief review of recent advances in the classification of mammals at higher levels using fossils and molecular clocks. It also discusses latest fossil discoveries from the Cretaceous - Eocene (66-55 m.y.) rocks of India and their relevance to our current understanding of placental mammal origins and diversifications.

High-resolution δ13C record of fossil wood and bulk organic matter from a deep Oligocene lacustrine succession, Bach Long Vi Island, Vietnam

Science.gov (United States)

Rizzi, M.; Schovsbo, N. H.; Fyhn, M. B. W.; Korte, C.

2017-12-01

We present a high-resolution stable isotope record based on bulk organic matter (δ13Corg) and fossil wood (δ13Cwood) originating from Oligocene deep lacustrine sediments cored on the Bach Long Vi Island, northern Gulf of Tonkin, offshore Vietnam. The sediments are exceptionally well preserved. They are thus excellently suited for a detailed stratigraphical analysis of the stable isotope record and as proxy for environmental and climatic changes within this period. The sediments were deposited in rapid subsiding, narrow and elongated fault-bound graben (Fyhn and Phach, 2015) and are represented by deep pelagic lacustrine organic-rich mud interrupted by numerous density-flow deposits (Hovikoski et al., 2016). The density-flow deposits contain abundant fragments of fossil wood. Therefore it was possible to obtain 262 coalified wood fragments together with 1063 bulk organic samples throughout the span of the core. This allowed to establish a high resolution stable C isotope record (δ13Corg and δ13Cwood). In addition 2464 handheld XRF determinations were carried out to further characterize the depositional environment (Rizzi et al., 2017). The organic carbon isotope trend from the 500 m core succession provides insight into the palaeoenvironmental changes of the lake during the Oligocene. Both, global and local factors control the δ13C variations. The aim of the study is to obtain pure global δ13Corg and δ13Cwood signals that would allow comparison of the studied sediments with coeval syn-rift successions in the South China Sea region and other parts of the world. [1] Fyhn and Phach (2015) Tectonics, 34(2): 290-312. [2] Hovikoski et al. (2016) Journal of Sedimentary Research, 86(8): 982-1007. [3] Rizzi et al. (2017) EGU General Assembly Abstract EGU 2017-17584.

Biology in the Anthropocene: Challenges and insights from young fossil records

Science.gov (United States)

Kidwell, Susan M.

2015-01-01

With overwhelming evidence of change in habitats, biologists today must assume that few, if any, study areas are natural and that biological variability is superimposed on trends rather than stationary means. Paleobiological data from the youngest sedimentary record, including death assemblages actively accumulating on modern land surfaces and seabeds, provide unique information on the status of present-day species, communities, and biomes over the last few decades to millennia and on their responses to natural and anthropogenic environmental change. Key advances have established the accuracy and resolving power of paleobiological information derived from naturally preserved remains and of proxy evidence for environmental conditions and sample age so that fossil data can both implicate and exonerate human stressors as the drivers of biotic change and permit the effects of multiple stressors to be disentangled. Legacy effects from Industrial and even pre-Industrial anthropogenic extirpations, introductions, (de)nutrification, and habitat conversion commonly emerge as the primary factors underlying the present-day status of populations and communities; within the last 2 million years, climate change has rarely been sufficient to drive major extinction pulses absent other human pressures, which are now manifold. Young fossil records also provide rigorous access to the baseline composition and dynamics of modern-day biota under pre-Industrial conditions, where insights include the millennial-scale persistence of community structures, the dominant role of physical environmental conditions rather than biotic interactions in determining community composition and disassembly, and the existence of naturally alternating states. PMID:25901315

Radiation exposures due to fossil fuel combustion

Science.gov (United States)

Beck, Harold L.

The current consensus regarding the potential radiation exposures resulting from the combustion of fossil fuels is examined. Sources, releases and potential doses to humans are discussed, both for power plants and waste materials. It is concluded that the radiation exposure to most individuals from any pathway is probably insignificant, i.e. only a tiny fraction of the dose received from natural sources in soil and building materials. Any small dose that may result from power-plant emissions will most likely be from inhalation of the small insoluble ash particles from the more poorly controlled plants burning higher than average activity fuel, rather than from direct or indirect ingestion of food grown on contaminated soil. One potentially significant pathway for exposure to humans that requires further evaluation is the effect on indoor external γ-radiation levels resulting from the use of flyash in building materials. The combustion of natural gas in private dwellings is also discussed, and the radiological consequences are concluded to be generally insignificant, except under certain extraordinary circumstances.

Animal behavior frozen in time: gregarious behavior of Early Jurassic lobsters within an ammonoid body chamber.

Directory of Open Access Journals (Sweden)

Adiël A Klompmaker

Full Text Available Direct animal behavior can be inferred from the fossil record only in exceptional circumstances. The exceptional mode of preservation of ammonoid shells in the Posidonia Shale (Lower Jurassic, lower Toarcian of Dotternhausen in southern Germany, with only the organic periostracum preserved, provides an excellent opportunity to observe the contents of the ammonoid body chamber because this periostracum is translucent. Here, we report upon three delicate lobsters preserved within a compressed ammonoid specimen of Harpoceras falciferum. We attempt to explain this gregarious behavior. The three lobsters were studied using standard microscopy under low angle light. The lobsters belong to the extinct family of the Eryonidae; further identification was not possible. The organic material of the three small lobsters is preserved more than halfway into the ammonoid body chamber. The lobsters are closely spaced and are positioned with their tails oriented toward each other. The specimens are interpreted to represent corpses rather than molts. The lobsters probably sought shelter in preparation for molting or against predators such as fish that were present in Dotternhausen. Alternatively, the soft tissue of the ammonoid may have been a source of food that attracted the lobsters, or it may have served as a long-term residency for the lobsters (inquilinism. The lobsters represent the oldest known example of gregariousness amongst lobsters and decapods in the fossil record. Gregarious behavior in lobsters, also known for extant lobsters, thus developed earlier in earth's history than previously known. Moreover, this is one of the oldest known examples of decapod crustaceans preserved within cephalopod shells.

Animal behavior frozen in time: gregarious behavior of Early Jurassic lobsters within an ammonoid body chamber.

Science.gov (United States)

Klompmaker, Adiël A; Fraaije, René H B

2012-01-01

Direct animal behavior can be inferred from the fossil record only in exceptional circumstances. The exceptional mode of preservation of ammonoid shells in the Posidonia Shale (Lower Jurassic, lower Toarcian) of Dotternhausen in southern Germany, with only the organic periostracum preserved, provides an excellent opportunity to observe the contents of the ammonoid body chamber because this periostracum is translucent. Here, we report upon three delicate lobsters preserved within a compressed ammonoid specimen of Harpoceras falciferum. We attempt to explain this gregarious behavior. The three lobsters were studied using standard microscopy under low angle light. The lobsters belong to the extinct family of the Eryonidae; further identification was not possible. The organic material of the three small lobsters is preserved more than halfway into the ammonoid body chamber. The lobsters are closely spaced and are positioned with their tails oriented toward each other. The specimens are interpreted to represent corpses rather than molts. The lobsters probably sought shelter in preparation for molting or against predators such as fish that were present in Dotternhausen. Alternatively, the soft tissue of the ammonoid may have been a source of food that attracted the lobsters, or it may have served as a long-term residency for the lobsters (inquilinism). The lobsters represent the oldest known example of gregariousness amongst lobsters and decapods in the fossil record. Gregarious behavior in lobsters, also known for extant lobsters, thus developed earlier in earth's history than previously known. Moreover, this is one of the oldest known examples of decapod crustaceans preserved within cephalopod shells.

Dental development in living and fossil orangutans.

Science.gov (United States)

Smith, Tanya M

2016-05-01

Numerous studies have investigated molar development in extant and fossil hominoids, yet relatively little is known about orangutans, the only great ape with an extensive fossil record. This study characterizes aspects of dental development, including cuspal enamel daily secretion rate, long-period line periodicities, cusp-specific molar crown formation times and extension rates, and initiation and completion ages in living and fossil orangutan postcanine teeth. Daily secretion rate and periodicities in living orangutans are similar to previous reports, while crown formation times often exceed published values, although direct comparisons are limited. One wild Bornean individual died at 4.5 years of age with fully erupted first molars (M1s), while a captive individual and a wild Sumatran individual likely erupted their M1s around five or six years of age. These data underscore the need for additional samples of orangutans of known sex, species, and developmental environment to explore potential sources of variation in molar emergence and their relationship to life history variables. Fossil orangutans possess larger crowns than living orangutans, show similarities in periodicities, and have faster daily secretion rate, longer crown formation times, and slower extension rates. Molar crown formation times exceed reported values for other fossil apes, including Gigantopithecus blacki. When compared to African apes, both living and fossil orangutans show greater cuspal enamel thickness values and periodicities, resulting in longer crown formation times and slower extension rates. Several of these variables are similar to modern humans, representing examples of convergent evolution. Molar crown formation does not appear to be equivalent among extant great apes or consistent within living and fossil members of Pongo or Homo. Copyright © 2016 The Author. Published by Elsevier Ltd.. All rights reserved.

Na, K, Ca, Mg, and U-series in fossil bone and the proposal of a radial diffusion-adsorption model of uranium uptake.

Science.gov (United States)

Cid, A S; Anjos, R M; Zamboni, C B; Cardoso, R; Muniz, M; Corona, A; Valladares, D L; Kovacs, L; Macario, K; Perea, D; Goso, C; Velasco, H

2014-10-01

Fossil bones are often the only materials available for chronological reconstruction of important archeological sites. However, since bone is an open system for uranium, it cannot be dated directly and therefore it is necessary to develop models for the U uptake. Hence, a radial diffusion-adsorption (RDA) model is described. Unlike the classic diffusion-adsorption (D-A) model, RDA uses a cylindrical geometry to describe the U uptake in fossil bones. The model was applied across a transverse section of a tibia of an extinct megamammal Macrauchenia patachonica from the La Paz Local Fauna, Montevideo State, Uruguay. Measurements of spatial distribution of Na, K, Ca, and Mg were also performed by neutron activation analysis (NAA). Gamma-ray spectrometric U-series dating was applied to determine the age of the bone sample. From U concentration profile, it was possible to observe the occurrence of a relatively slow and continuous uranium uptake under constant conditions that had not yet reached equilibrium, since the uranium distribution is a ∪-shaped closed-system. Predictions of the RDA model were obtained for a specific geochemical scenario, indicating that the effective diffusion coefficient D/R in this fossil bone is (2.4 ± 0.6)10(-12) cm(2)s(-1). Mean values of Na, K, Ca, and Mg contents along the radial line of the fossil tibia are consistent with the expected behavior for spatial distributions of these mineral elements across a modern bone section. This result indicates that the fossil tibia may have its mineral structure preserved. Copyright © 2014 Elsevier Ltd. All rights reserved.

Fossilized intact polar lipids of photosynthetic organisms in ancient subsurface sediments

Science.gov (United States)

Bauersachs, T.; Schouten, S.; Hopmans, E. C.; Sinninghe Damsté, J. S.

2009-12-01

(47 Ma) and the Eocene Green-River Formation (ca. 50 Ma). The presence of IPLs such as HGs in these ancient sediments is remarkable, given the assumed lability of IPLs with glycosidic or phosphoric head groups. Our data, however, show that HGs with glycosidically bound head groups, unambiguously derived from photoautotrophic organisms living in the photic zone of the water column, can fossilize and be well preserved in the sedimentary record. The presence of HGs in fossil sediments, thus, raises the question whether certain IPLs, especially those with glycosidic head groups, may be more recalcitrant than previously thought and can constitute a significant fossil component of the so-called IPL fraction. This has important consequences (1) for the use of IPLs as a proxy of living prokaryotic biomass and (2) for the conclusion that Archaea are the main standing stock of prokaryotes in the deep-biosphere.

Security of supply: a neglected fossil fuel externality

International Nuclear Information System (INIS)

Cavallo, A.J.

1995-01-01

Various groups have attempted to set a monetary value on the externalities of fossil fuel usage based on damages caused by emissions of particulates, sulfur dioxide, and oxides of nitrogen and carbon. One externality that has been neglected in this type of analysis, however, is the cost of maintaining a secure supply of fossil fuels. Military expenditures for this purpose are relatively easy to quantify based on US Department of Defense and Office of Management and Budget figures, and amount to between $1 and more than $3 per million Btu, based on total fossil fuel consumption in the US. Open acknowledgment of such expenses would, at the very least, have a profound effect on the perceived competitiveness of all non-fossil fuel technologies. It should also provide a simple and easily comprehended rationale for an energy content (Btu) charge on all fossil fuels. (Author)

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.

Checking collagen preservation in archaeological bone by non-destructive studies (Micro-CT and IBA)

Science.gov (United States)

Beck, L.; Cuif, J.-P.; Pichon, L.; Vaubaillon, S.; Dambricourt Malassé, A.; Abel, R. L.

2012-02-01

The material to be studied is a piece of human skull discovered (1999) in Pleistocene sediments from the Orsang river (Gujarat state, India). From anatomical view point, this skull is highly composite: modern Homo sapiens characters are associated to undoubtedly more ancient features. Absolute dating by 14C is critical to understand this discovery. Prior to dating measurements, non-destructive studies have been carried out. Micro-CT reconstruction (X-ray microtomography) and Ion Beam Analysis (IBA) have been undertaken to check the structural preservation of the fossil and the collagen preservation. PIXE elemental map was used to select well-preserved bone area. RBS/EBS and NRA were used for light element quantification, in particular C, N and O contents. We also demonstrate that the PIXE-RBS/EBS combination is a effective tool for the whole characterization of archaeological and recent bones by analysing in one experiment both mineral and organic fractions. We have shown that the archaeological bone, a fragment of the potentially oldest modern Indian, is enough preserved for radiocarbon dating. We propose that Elastic Backscattering Spectrometry (EBS) using 3 MeV protons could be a good non destructive alternative to conventional CHN method using Carbon-Hydrogen-Nitrogen analyzer for measuring C and N before 14C dating.

Checking collagen preservation in archaeological bone by non-destructive studies (Micro-CT and IBA)

International Nuclear Information System (INIS)

Beck, L.; Cuif, J.-P.; Pichon, L.; Vaubaillon, S.; Dambricourt Malassé, A.; Abel, R.L.

2012-01-01

The material to be studied is a piece of human skull discovered (1999) in Pleistocene sediments from the Orsang river (Gujarat state, India). From anatomical view point, this skull is highly composite: modern Homo sapiens characters are associated to undoubtedly more ancient features. Absolute dating by 14 C is critical to understand this discovery. Prior to dating measurements, non-destructive studies have been carried out. Micro-CT reconstruction (X-ray microtomography) and Ion Beam Analysis (IBA) have been undertaken to check the structural preservation of the fossil and the collagen preservation. PIXE elemental map was used to select well-preserved bone area. RBS/EBS and NRA were used for light element quantification, in particular C, N and O contents. We also demonstrate that the PIXE-RBS/EBS combination is a effective tool for the whole characterization of archaeological and recent bones by analysing in one experiment both mineral and organic fractions. We have shown that the archaeological bone, a fragment of the potentially oldest modern Indian, is enough preserved for radiocarbon dating. We propose that Elastic Backscattering Spectrometry (EBS) using 3 MeV protons could be a good non destructive alternative to conventional CHN method using Carbon–Hydrogen–Nitrogen analyzer for measuring C and N before 14 C dating.

Checking collagen preservation in archaeological bone by non-destructive studies (Micro-CT and IBA)

Energy Technology Data Exchange (ETDEWEB)

Beck, L., E-mail: lucile.beck@cea.fr [C2RMF - UMR171 CNRS, Centre de Recherche et de Restauration des Musees de France, Palais du Louvre, Porte des Lions, 14 quai Francois Mitterrand, 75001 Paris (France); CEA, DEN, Service de Recherches de Metallurgie Physique, Laboratoire JANNUS, 91191 Gif-sur-Yvette (France); Cuif, J.-P. [UMR IDES 8148, Universite Paris XI-Orsay, 91405 Orsay cedex (France); Pichon, L. [C2RMF - UMR171 CNRS, Centre de Recherche et de Restauration des Musees de France, Palais du Louvre, Porte des Lions, 14 quai Francois Mitterrand, 75001 Paris (France); Vaubaillon, S. [CEA, INSTN, Laboratoire JANNUS, 91191 Gif-sur-Yvette (France); Dambricourt Malasse, A. [Departement de Prehistoire, Museum national d' Histoire naturelle, UMR 7194 - CNRS, Institut de Paleontologie Humaine, 1, rue Rene Panhard, 75013 Paris (France); Abel, R.L. [The Natural History Museum, London (United Kingdom)

2012-02-15

The material to be studied is a piece of human skull discovered (1999) in Pleistocene sediments from the Orsang river (Gujarat state, India). From anatomical view point, this skull is highly composite: modern Homo sapiens characters are associated to undoubtedly more ancient features. Absolute dating by {sup 14}C is critical to understand this discovery. Prior to dating measurements, non-destructive studies have been carried out. Micro-CT reconstruction (X-ray microtomography) and Ion Beam Analysis (IBA) have been undertaken to check the structural preservation of the fossil and the collagen preservation. PIXE elemental map was used to select well-preserved bone area. RBS/EBS and NRA were used for light element quantification, in particular C, N and O contents. We also demonstrate that the PIXE-RBS/EBS combination is a effective tool for the whole characterization of archaeological and recent bones by analysing in one experiment both mineral and organic fractions. We have shown that the archaeological bone, a fragment of the potentially oldest modern Indian, is enough preserved for radiocarbon dating. We propose that Elastic Backscattering Spectrometry (EBS) using 3 MeV protons could be a good non destructive alternative to conventional CHN method using Carbon-Hydrogen-Nitrogen analyzer for measuring C and N before {sup 14}C dating.

Fossil energy: From laboratory to marketplace

International Nuclear Information System (INIS)

1992-03-01

The purpose of this work is to provide a summary description of the role of advanced research in the overall Fossil Energy R ampersand D program successes. It presents the specific Fossil Energy advanced research products that have been adopted commercially or fed into other R ampersand D programs as part of the crosscutting enabling technology base upon which advanced systems are based

Lessons learned from fossil FAC assessments

Energy Technology Data Exchange (ETDEWEB)

Dooley, R. Barry; Shields, Kevin J. [Structural Integrity Associates, Inc., Oakville, ON (Canada); Shulder, Stephen J. [Structural Integrity Associates, Inc., Annapolis, MD (United States)

2010-09-15

In their work the authors have noted great diversity in the Flow-Accelerated Corrosion (FAC) Programs used at conventional fossil power plants. The results and findings of FAC Program assessments conducted at 22 conventional plants are summarized and discussed. By comparing the FAC Program characteristics and relevant unit features with damage and failure experiences, a number of common factors requiring attention from fossil utility organizations have been identified. The assessment experiences have also provided a picture of trends in specific FAC activities and general awareness within the conventional fossil fleet. One of the most important aspects of these studies is that while a few new locations of FAC have been found, there is some consolidation of the most frequently found locations. (orig.)

FOSSIL SYSTEMS IN THE 400d CLUSTER CATALOG

International Nuclear Information System (INIS)

Voevodkin, Alexey; Borozdin, Konstantin; Heitmann, Katrin; Habib, Salman; Vikhlinin, Alexey; Mescheryakov, Alexander; Burenin, Rodion; Hornstrup, Allan

2010-01-01

We report the discovery of seven new fossil systems in the 400d cluster survey. Our search targets nearby, z ≤ 0.2, and X-ray bright, L X ≥ 10 43 erg s -1 , clusters of galaxies. Where available, we measure the optical luminosities from Sloan Digital Sky Survey images, thereby obtaining uniform sets of both X-ray and optical data. Our selection criteria identify 12 fossil systems, out of which five are known from previous studies. While in general agreement with earlier results, our larger sample size allows us to put tighter constraints on the number density of fossil clusters. It has been previously reported that fossil groups are more X-ray bright than other X-ray groups of galaxies for the same optical luminosity. We find, however, that the X-ray brightness of massive fossil systems is consistent with that of the general population of galaxy clusters and follows the same L X -L opt scaling relation.

Fossil Fuels, Backstop Technologies, and Imperfect Substitution

NARCIS (Netherlands)

van der Meijden, G.C.; Pittel, Karen; van der Ploeg, Frederick; Withagen, Cees

2014-01-01

This chapter studies the transition from fossil fuels to backstop technologies in a general equilibrium model in which growth is driven by research and development. The analysis generalizes the existing literature by allowing for imperfect substitution between fossil fuels and the new energy

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)

Fossil Energy Program semiannual progress report for October 1991--March 1992

Energy Technology Data Exchange (ETDEWEB)

Judkins, R.R.

1992-11-01

This report covers progress made during the period October 1, 1991, through March 31, 1992, 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 discussed are under the following projects: materials research and developments; environmental analysis support; coal conversion development; coal combustion research; and fossil fuels supplies modeling and research.

Optimization of preservation activities and preservation engineering (1)

International Nuclear Information System (INIS)

Aoki, Takayuki; Mimaki, Hidehito; Oda, Mitsuyuki

2004-01-01

In order to deal with the optimization of preservation activities and 'preservation engineering' which makes it possible, the relation between general society and preservation, the content and the structure of preservation activities, and the viewpoint and the approach of the optimization of the preventive preservation are described. The optimization of the preventive preservation is shown respectively in the four stages of planning, implementation, result evaluation and countermeasure. (K. Kato)

Na, K, Ca, Mg, and U-series in fossil bone and the proposal of a radial diffusion–adsorption model of uranium uptake

International Nuclear Information System (INIS)

Cid, A.S.; Anjos, R.M.; Zamboni, C.B.; Cardoso, R.; Muniz, M.; Corona, A.; Valladares, D.L.

2014-01-01

Fossil bones are often the only materials available for chronological reconstruction of important archeological sites. However, since bone is an open system for uranium, it cannot be dated directly and therefore it is necessary to develop models for the U uptake. Hence, a radial diffusion–adsorption (RDA) model is described. Unlike the classic diffusion–adsorption (D–A) model, RDA uses a cylindrical geometry to describe the U uptake in fossil bones. The model was applied across a transverse section of a tibia of an extinct megamammal Macrauchenia patachonica from the La Paz Local Fauna, Montevideo State, Uruguay. Measurements of spatial distribution of Na, K, Ca, and Mg were also performed by neutron activation analysis (NAA). Gamma-ray spectrometric U-series dating was applied to determine the age of the bone sample. From U concentration profile, it was possible to observe the occurrence of a relatively slow and continuous uranium uptake under constant conditions that had not yet reached equilibrium, since the uranium distribution is a ∪-shaped closed-system. Predictions of the RDA model were obtained for a specific geochemical scenario, indicating that the effective diffusion coefficient D/R in this fossil bone is (2.4 ± 0.6)10 −12 cm 2 s −1 . Mean values of Na, K, Ca, and Mg contents along the radial line of the fossil tibia are consistent with the expected behavior for spatial distributions of these mineral elements across a modern bone section. This result indicates that the fossil tibia may have its mineral structure preserved. - Highlights: • The Radial diffusion–adsorption (RDA) model is described. • RDA uses a cylindrical geometry to describe the U uptake in fossil bones. • We show new data for an extinct Macrauchenia patachonica from Uruguay. • Spatial distributions of Na, K, Ca, Mg, and U across a fossil bone section. • Gamma-ray spectrometric U-series dating was applied to determine its age

Fossiler i Grønland. 2. del

DEFF Research Database (Denmark)

Harper, David Alexander Taylor; Lindow, Bent Erik Kramer

2009-01-01

Dette er anden og sidste del af POST Greenlands serie om fossiler i Grønland med tre frimærker, der beretter om de mange og spændende fossilfund fra Grønland. Mærkerne fortsætter vores rejse gennem nogle af nøglebegivenhederne i livets historie, smukt illustreret af endnu flere unikke fossiler....... Disse tre fossiler, en plante, et bløddyr og et hvirveldyr, er fra de yngre aflejringer i Grønland med aldre spændende fra for 200 millioner og indtil kun 8.000 år siden....

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.

Proceedings of the Seventh Annual Conference on Fossil Energy Materials. Fossil Energy AR and TD Materials Program

Energy Technology Data Exchange (ETDEWEB)

Cole, N.C.; Judkins, R.R. [comps.

1993-07-01

Objective of the AR&TD Materials Program is to conduct research and development on materials for longer-term fossil energy applications as well as for generic needs of various fossil fuel technologies. The 37 papers are arranged into 3 sessions: ceramics, new alloys/intermetallics, and new alloys/advanced austenitics. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database.

Coastal Microstructure: From Active Overturn to Fossil Turbulence

Science.gov (United States)

Tau Leung, Pak

2011-11-01

The Remote Anthropogenic Sensing Program was a five year effort (2001- 2005) to examine subsurface phenomena related to a sewage outfall off the coast of Oahu, Hawaii. This research has implications for basic ocean hydrodynamics, particularly for a greatly improved understanding of the evolution of turbulent patches. It was the first time a microstructure measurement was used to study such a buoyancy-driven turbulence generated by a sea-floor diffuser. In 2004, two stations were selected to represent the near field and ambient conditions. They have nearly identical bathymetrical and hydrographical features and provide an ideal environment for a control experiment. Repeated vertical microstructure measurements were performed at both stations for 20 days. A time series of physical parameters was collected and used for statistical analysis. After comparing the data from both stations, it can be concluded that the turbulent mixing generated by the diffuser contributes to the elevated dissipation rate observed in the pycnocline and bottom boundary layer. To further understand the mixing processes in both regions, data were plotted on a Hydrodynamic Phase Diagram. The overturning stages of the turbulent patches are identified by Hydrodynamic Phase Diagram. This technique provides detailed information on the evolution of the turbulent patches from active overturns to fossilized scalar microstructures in the water column. Results from this study offer new evidence to support the fossil turbulence theory. This study concluded that: 1. Field Data collected near a sea-floor outfall diffuser show that turbulent patches evolve from active (overturning) to fossil (buoyancy-inhibited) stages, consistent with the process of turbulent patch evolution proposed by fossil turbulence theory. 2. The data show that active (overturning) and fossil (buoyancy-inhibited) patches have smaller length scales than the active+fossil (intermediate) stage of patch evolution, consistent with fossil

Control of SO2 and NOx emissions from fossil fuel-fired power plants: Research and practice of TPRI

International Nuclear Information System (INIS)

Ming-Chuan Zhang.

1993-01-01

The generation of electric power in China has been dominated by coal for many years. By the end of 1990, total installed generating capacity reached 135 GW, of which fossil fuel-fired plants accounted for 74 percent. The total electricity generated reached 615 TWh, with fossil fuels accounting for 80.5 percent. About 276 million tons of raw coal are consumed in these fossil fuel-burning units per year, accounting for about 25 percent of the total output of the country. According to the government, by the year 2000, the total installed capacity of Chinese power systems should be at least 240 GW, of which fossil fuels will account for about 77 percent. The coal required for power generation will increase to about 530 million tons per year, accounting for about 38 percent of the total coal output. So, it is obvious that coal consumed in coal-fired power plants occupies a very important place in the national fuel balance. The current environmental protection standards, which are based on ground-level concentrations of pollutants, do not effectively lead to the control of pollution emission concentrations or total SO 2 emissions. Due to the practical limitations of the Chinese economy, there is a limited capability to introduce advanced sulfur emission control technologies. Thus, except for the two 360 MW units imported from Japan for the Luohuang Power Plant in Shichuan province, all the other fossil fuel-fired units have not yet adopted any kind of SO 2 removal measures. The Luohuang units are equipped with Mitsubishi limestone flue gas desulfurization systems. Because of the lack of effective pollution control technologies, large areas of the country have been seriously polluted by SO 2 , and some of them even by acid rain

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.

The first evidence of trace fossils and pseudo-fossils in the continental interlava volcaniclastic sediments on the Faroe Islands

Czech Academy of Sciences Publication Activity Database

Pokorný, R.; Krmíček, Lukáš; Árting, U. E.

2015-01-01

Roč. 63, č. 1 (2015), s. 45-57 ISSN 2245-7070 Institutional support: RVO:67985831 Keywords : Faroe Islands * trace fossils * pseudo- fossils * volcaniclastic sediments Subject RIV: DB - Geology ; Mineralogy Impact factor: 0.889, year: 2015 http://2dgf.dk/xpdf/bull63-45-57.pdf

Fossil Energy Program semiannual progress report for April 1992-- September 1992

Energy Technology Data Exchange (ETDEWEB)

Judkins, R.R.

1992-12-01

This report covers progress made during the period April 1, 1992, through September 30, 1992, 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 Office of Naval Petroleum and Oil Shale Reserves, and the US Agency for International Development.

Constraints of fossil fuels depletion on global warming projections

International Nuclear Information System (INIS)

Chiari, Luca; Zecca, Antonio

2011-01-01

A scientific debate is in progress about the intersection of climate change with the new field of fossil fuels depletion geology. Here, new projections of atmospheric CO 2 concentration and global-mean temperature change are presented, should fossil fuels be exploited at a rate limited by geological availability only. The present work starts from the projections of fossil energy use, as obtained from ten independent sources. From such projections an upper bound, a lower bound and an ensemble mean profile for fossil CO 2 emissions until 2200 are derived. Using the coupled gas-cycle/climate model MAGICC, the corresponding climatic projections out to 2200 are obtained. We find that CO 2 concentration might increase up to about 480 ppm (445-540 ppm), while the global-mean temperature increase w.r.t. 2000 might reach 1.2 deg. C (0.9-1.6 deg. C). However, future improvements of fossil fuels recovery and discoveries of new resources might lead to higher emissions; hence our climatic projections are likely to be underestimated. In the absence of actions of emissions reduction, a level of dangerous anthropogenic interference with the climate system might be already experienced toward the middle of the 21st century, despite the constraints imposed by the exhaustion of fossil fuels. - Highlights: → CO 2 and global temperature are projected under fossil fuels exhaustion scenarios. → Temperature is projected to reach a minimum of 2 deg. C above pre-industrial. → Temperature projections are possibly lower than the IPCC ones. → Fossil fuels exhaustion will not avoid dangerous global warming.

Constraints of fossil fuels depletion on global warming projections

Energy Technology Data Exchange (ETDEWEB)

Chiari, Luca, E-mail: chiari@science.unitn.it [Department of Physics, University of Trento, Via Sommarive 14, 38123 Povo (Italy); Zecca, Antonio, E-mail: zecca@science.unitn.it [Department of Physics, University of Trento, Via Sommarive 14, 38123 Povo (Italy)

2011-09-15

A scientific debate is in progress about the intersection of climate change with the new field of fossil fuels depletion geology. Here, new projections of atmospheric CO{sub 2} concentration and global-mean temperature change are presented, should fossil fuels be exploited at a rate limited by geological availability only. The present work starts from the projections of fossil energy use, as obtained from ten independent sources. From such projections an upper bound, a lower bound and an ensemble mean profile for fossil CO{sub 2} emissions until 2200 are derived. Using the coupled gas-cycle/climate model MAGICC, the corresponding climatic projections out to 2200 are obtained. We find that CO{sub 2} concentration might increase up to about 480 ppm (445-540 ppm), while the global-mean temperature increase w.r.t. 2000 might reach 1.2 deg. C (0.9-1.6 deg. C). However, future improvements of fossil fuels recovery and discoveries of new resources might lead to higher emissions; hence our climatic projections are likely to be underestimated. In the absence of actions of emissions reduction, a level of dangerous anthropogenic interference with the climate system might be already experienced toward the middle of the 21st century, despite the constraints imposed by the exhaustion of fossil fuels. - Highlights: > CO{sub 2} and global temperature are projected under fossil fuels exhaustion scenarios. > Temperature is projected to reach a minimum of 2 deg. C above pre-industrial. > Temperature projections are possibly lower than the IPCC ones. > Fossil fuels exhaustion will not avoid dangerous global warming.

Finding fossils in new ways: an artificial neural network approach to predicting the location of productive fossil localities.

Science.gov (United States)

Anemone, Robert; Emerson, Charles; Conroy, Glenn

2011-01-01

Chance and serendipity have long played a role in the location of productive fossil localities by vertebrate paleontologists and paleoanthropologists. We offer an alternative approach, informed by methods borrowed from the geographic information sciences and using recent advances in computer science, to more efficiently predict where fossil localities might be found. Our model uses an artificial neural network (ANN) that is trained to recognize the spectral characteristics of known productive localities and other land cover classes, such as forest, wetlands, and scrubland, within a study area based on the analysis of remotely sensed (RS) imagery. Using these spectral signatures, the model then classifies other pixels throughout the study area. The results of the neural network classification can be examined and further manipulated within a geographic information systems (GIS) software package. While we have developed and tested this model on fossil mammal localities in deposits of Paleocene and Eocene age in the Great Divide Basin of southwestern Wyoming, a similar analytical approach can be easily applied to fossil-bearing sedimentary deposits of any age in any part of the world. We suggest that new analytical tools and methods of the geographic sciences, including remote sensing and geographic information systems, are poised to greatly enrich paleoanthropological investigations, and that these new methods should be embraced by field workers in the search for, and geospatial analysis of, fossil primates and hominins. Copyright © 2011 Wiley-Liss, Inc.

Energy properties of solid fossil fuels and solid biofuels

International Nuclear Information System (INIS)

Holubcik, Michal; Jandacka, Jozef; Kolkova, Zuzana

2016-01-01

The paper deals about the problematic of energy properties of solid biofuels in comparison with solid fossil fuels. Biofuels are alternative to fossil fuels and their properties are very similar. During the experiments were done in detail experiments to obtain various properties of spruce wood pellets and wheat straw pellets like biofuels in comparison with brown coal and black coal like fossil fuels. There were tested moisture content, volatile content, fixed carbon content, ash content, elementary analysis (C, H, N, S content) and ash fusion temperatures. The results show that biofuels have some advantages and also disadvantages in comparison with solid fossil fuels.

The strategic value of fossil fuels: challenges and responses

International Nuclear Information System (INIS)

1996-01-01

Several speeches of the conference concerning the strategic value of fossil fuels that was held on May 8 to 11, 1995 in Houston, Texas are presented. The current and future importance of fossil fuels in energy consumption throughout the world is highlighted. The role of developing countries in the fossil fuels market is increasing, and these countries need some assistance from developed countries to develop. International and regional cooperation seems to be a good way to ensure economic growth. The importance of fossil fuels is shown by the growth of international coal and natural gas trade. (TEC)

Energy properties of solid fossil fuels and solid biofuels

Energy Technology Data Exchange (ETDEWEB)

Holubcik, Michal, E-mail: michal.holubcik@fstroj.uniza.sk; Jandacka, Jozef, E-mail: jozef.jandacka@fstroj.uniza.sk [University of Žilina, Faculty of Mechanical Engineering, Department of Power Engineering, Univerzitná 8215/1, 010 26 Žilina (Slovakia); Kolkova, Zuzana, E-mail: zuzana.kolkova@rc.uniza.sk [Research centre, University of Žilina, Univerzitna 8215/1, 010 26 Žilina (Slovakia)

2016-06-30

The paper deals about the problematic of energy properties of solid biofuels in comparison with solid fossil fuels. Biofuels are alternative to fossil fuels and their properties are very similar. During the experiments were done in detail experiments to obtain various properties of spruce wood pellets and wheat straw pellets like biofuels in comparison with brown coal and black coal like fossil fuels. There were tested moisture content, volatile content, fixed carbon content, ash content, elementary analysis (C, H, N, S content) and ash fusion temperatures. The results show that biofuels have some advantages and also disadvantages in comparison with solid fossil fuels.

Microelements in fossil bones and the estimation of age

International Nuclear Information System (INIS)

Besliu, C.; Olariu, A.; Popescu, I.; Badica, Th.

1993-01-01

Neutron activation analysis was used to determine microelements fossil bones and the correlation was found between some elements and the C-14 estimated age of the bones. Fluorine, uranium and manganese content in the bones structure increases with the time elapsed, during fossilization. This means that measurable concentrations of these elements and known environmental conditions could provide a relative dating tool of bones beyond the 70 ky radiocarbon limit, for paleolithic archaeology. Sodium, scandium, iron, and zinc have been also determined in fossil bones, but a relation with the increasing antiquity of the fossil has been observed. (Author)

Optimization of preservation activities and preservation engineering (2)

International Nuclear Information System (INIS)

Aoki, Takayuki; Mimaki, Hidehito; Oda, Mitsuyuki

2004-01-01

In order to deal with the optimization of preservation activities and 'preservation engineering' which makes it possible, the viewpoint and the approach of the optimization of the ex post facto preservation and the content to be possessed in 'preservation engineering' are described. The optimization of the ex post facto preservation is shown respectively in the four stages of planning, implementation, result evaluation and countermeasure. (K. Kato)

Global exergetic dimension of hydrogen use in reducing fossil fuel consumption

International Nuclear Information System (INIS)

Adnan Midilli; Ibrahim Dincer

2009-01-01

In this paper, hydrogen is considered as a renewable and sustainable solution for minimizing the fossil fuel based-global irreversibility coefficient of global fossil fuel consumption and combating global warming and studied exergetically through a parametric performance analysis. The environmental impact results are then compared with the ones obtained for fossil fuels. In this regard, some exergetic expressions such as global waste exergy factor, global irreversibility coefficient and hydrogen based-global exergetic indicator. In order to investigate the role of hydrogen use at minimizing the fossil fuel based global irreversibility, the actual fossil fuel consumption data are taken from the literature. Due to the unavailability of appropriate hydrogen data for analysis, it is assumed that the utilization ratios of hydrogen are ranged between 0 and 1. Consequently, if exergetic utilization ratio of hydrogen from non-fossil fuel sources at a certain exergetic utilization ratio of fossil fuels increases, the fossil fuel based-global irreversibility coefficient will decrease. (author)

100 years of discovery of the Burgess Shale 1909-2009 : a celebration of the discovery of the world's most important fossils

International Nuclear Information System (INIS)

2009-01-01

The centennial celebration of the discovery of the Burgess Shale consisted of informative science presentations to the general public. Scientific presenters also participated in guided hikes in Yoho National Park within the Canadian Rockies where the Burgess Shale can be found. The first Burgess Shale fossils were discovered in 1909 by Charles D. Walcott. Thousands of specimens have since been collected from the quarry named after him. The informative science presentations described the burst of biodiversity of marine plants and marine invertebrate animals that lived in a shallow sea in the vicinity of a massive carbonate reef during the Cambrian Period. They described the unusual conditions that allowed for the very rare preservation of the animals in the Burgess Shale. The Burgess Shale fossils merit special interest because they reveal how animal life appeared on Earth better than any other fossil record. In addition to the geological history of the Burgess Shale area, the centennial lectures also addressed topics such as climate and the geological record of climate change; the influence of continental drift on evolution; and fluid geochemistry in the Western Canada Foreland Basin and paleoclimate influence. The Burgess Shale was designated a UNESCO World Heritage Site in 1981 as it provides key information about evolution of life on Earth. refs. figs

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.

Lu-Hf isotope systematics of fossil biogenic apatite and their effects on geochronology

Science.gov (United States)

Herwartz, Daniel; Münker, Carsten; Tütken, Thomas; Hoffmann, J. Elis; Wittke, Andreas; Barbier, Bruno

2013-01-01

Reliable methods for direct dating of biogenic apatite from pre-Pleistocene fossils are currently not available, and recent attempts using the Lu-Hf decay system yielded highly inaccurate ages for both bones and teeth. The geological processes accounting for this poor accuracy of Lu-Hf chronometry are not yet understood. Here we explore Lu-Hf systematics in fossil bones and teeth in detail, by applying five different sample digestion techniques that are tested on bones and composites of bone and sediment. Our current dataset implies that dissolution methods only slightly affect the resulting Lu-Hf ages, while clear differences between the individual digestion techniques became apparent for element concentrations. By analysing the insoluble leftovers from incomplete sample dissolution, four main reservoirs of Hf in fossil bones were identified: (1) a radiogenic end-member associated with apatite; (2) an unradiogenic end-member represented by the authigenic minerals or the embedding sediment; (3) a highly unradiogenic end-member that can be attributed to detrital zircon; and (4) a moderately soluble phase (probably a Zr(Hf)-phosphate) that yielded very low Lu/Hf but a highly radiogenic Hf isotope composition at the same time. This Zr(Hf)-phase must have been precipitated within the fossil bone sample at a late stage of burial history, thereby incorporating radiogenic 176Hf released from apatite surfaces over geological timescales. A second focus of our study is the effect of different sediment matrices and of crystal size on the preservation of pristine Lu-Hf isotope compositions in bioapatite. Because near-depositional Lu-Hf ages of phosphate fossils have previously been reported for the London Clay (England) and a calcareous marl from Tendaguru (Tanzania), we herein investigate specimens fossilised in carbonate matrices (calcareous marl from Oker, Germany; carbonate concretions from the Santana Formation, Brazil; carbonate from the Eifel, Germany) and argillaceous

Magnetohydrodynamic dynamos in the presence of fossil magnetic fields

International Nuclear Information System (INIS)

Boyer, D.W.

1982-01-01

A fossil magnetic field embedded in the radiative core of the Sun has been thought possible for some time now. However, such a fossil magnetic field has, a priori, not been considered a visible phenomenon due to the effects of turbulence in the solar convection zone. Since a well developed theory (referred to herein as magnetohydrodynamic dynamo theory) exists for describing the regeneration of magnetic fields in astrophysical objects like the Sun, it is possible to quantitatively evaluate the interaction of a fossil magnetic field with the magnetohydrodynamic dynamo operating in the solar convection zone. In this work, after a brief description of the basic dynamo equations, a spherical model calculation of the solar dynamo is introduced. First, the interaction of a fossil magnetic field with a dynamo in which the regeneration mechanisms of cyclonic convection and large-scale, nonuniform rotation are confined to spherical shells is calculated. It is argued that the amount of amplification or suppression of a fossil magnetic field will be smallest for a uniform distribution of cyclonic convection and nonuniform rotation, as expected in the Sun. Secondly, the interaction of a fossil magnetic field with a dynamo having a uniform distribution of cyclonic convection and large-scale, nonuniform rotation is calculated. It is found that the dipole or quadrupole moments of a fossil magnetic field are suppressed by factors of -0.35 and -0.37, respectively

Are bison exotic in the Wrangell-St. Elias National Park and Preserve?

Science.gov (United States)

Peek, James M.; Miquelle, Dale G.; Wright, R. Gerald

1987-03-01

The effect of past distributions of animal populations now extinct in an area from unknown causes is considered relative to their status as exotic or native in national parks. The example is the bison (Bison bison) on the Copper and Chitina river drainages in Alaska in the USA which was introduced prior to establishment of Wrangell-St. Elias National Park and Preserve. The fossil record suggests that bison were present as recently as 500 years ago in Alaska. The policy of the US National Park Service to maintain natural ecosystems and restrict or eliminate exotic species raises the issue of whether this species should be treated as exotic or native.

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....

{sup 14}C AMS measurements in tree rings to estimate local fossil CO{sub 2} in Bosco Fontana forest (Mantova, Italy)

Energy Technology Data Exchange (ETDEWEB)

Capano, Manuela, E-mail: capanomanuela@tiscali.i [CIRCE, Dipartimento di Scienze Ambientali, Seconda Universita di Napoli, and INNOVA, Via Vivaldi, 43 81100 Caserta (Italy); Marzaioli, Fabio; Sirignano, Carmina; Altieri, Simona; Lubritto, Carmine; D' Onofrio, Antonio; Terrasi, Filippo [CIRCE, Dipartimento di Scienze Ambientali, Seconda Universita di Napoli, and INNOVA, Via Vivaldi, 43 81100 Caserta (Italy)

2010-04-15

Radiocarbon concentration in atmosphere changes overtime due to anthropogenic and natural factors. Species growth preserves the local atmospheric radiocarbon signature over their life span in the annual tree rings and make it possible to use tree rings for the monitoring of changes in fossil-fuel emissions due to an increase of traffic exhaust, during the last decades. In this paper, the CIRCE AMS system has been used to measure the {sup 14}C concentration in tree rings of plants grown near an industrial area and a very busy State Road, in a forest in north Italy. Preliminary results related to tree rings of several years of plants respectively near and far the emitting sources are displayed, in order to estimate the local pollution effect. It is possible to find a dilution in years 2000 and 2006 in both the trees analysed, but not enough data have been analysed yet in order to distinguish the fossil dilution derived from the street vehicular traffic or that from the industries.

Proceedings of the sixth annual conference on fossil energy materials. Fossil Energy AR and TD Mateials Program

Energy Technology Data Exchange (ETDEWEB)

Cole, N.C.; Judkins, R.R. [comps.

1992-07-01

The Sixth Annual Conference on Fossil Energy Materials was held in Oak Ridge, Tennessee, on May 12--14, 1992. The meeting was sponsored by the US Department of Energy`s Office of Fossil Energy through the Advanced Research and Technology Development (AR&TD) Materials Program, and ASM International. The objective of the AR&TD Materials Program is to conduct research and development on materials for longer-term fossil energy applications as well as for generic needs of various fossil fuel technologies. The management of the Program has been decentralized to the DOE Field Office, Oak Ridge with Oak Ridge National Laboratory (ORNL) as the technical support contractor. The research is performed by staff members at ORNL and by a substantial number of researchers at other national laboratories, universities, and in private industry. The work is divided into the following categories: (1) ceramics, (2) development and corrosion resistance of iron aluminide, advanced austenitic and chromium-niobium alloys, and (3) technology assessment and technology transfer. This conference is held each year to review the work on all of the projects of the Program. The agenda for the meeting is given in Appendix A, and a list of attendees is presented in Appendix B. ASM International cosponsored the conference, for which we are especially grateful.

China's INDC and non-fossil energy development

Directory of Open Access Journals (Sweden)

Jian-Kun He

2015-09-01

Full Text Available Global climate change promotes the energy system reform. Achieving a high proportion of renewable energy becomes the major countries' energy strategy. As proposed in its Intended Nationally Determined Contributions (INDC, China intends to raise the proportion of non-fossil energy in primary energy consumption to about 20% by 2030. That ambitious goal means the non-fossil energy supplies by 2030 will be 7–8 times that of 2005, and the annual increase rate is more than 8% within the 25 years. Besides, the capacity of wind power, solar power, hydropower and nuclear power reaches 400 GW, 350 GW, 450 GW, and 150 GW respectively, and China's non-fossil power capacity is even greater than the U.S.'s total power capacity. In addition, the scale of natural gas increases. Consequently, by 2030, the proportion of coal falls from the current 70% to below 50%, and the CO2 intensity of energy consumption decreases by 20% compared with the level of 2005, which play important roles in significantly reducing the CO2 intensity of GDP. Since China has confirmed to achieve the CO2 emissions peak around 2030, at that time, the newly added energy demand will be satisfied by non-fossil energy, and the consumption of fossil fuel will stop growing. By 2030, non-fossil energy accounts for 20%, and the large scale and sound momentum of new and renewable energy industry will support the growth of total energy demand, which plays a key role in CO2 emissions peaking and beginning to decline, and lays the foundation for establishing a new energy system dominated by new and renewable energy in the second half of the 21st century as well as finally achieving the CO2 zero-emission.

Giving the early fossil record of sponges a squeeze.

Science.gov (United States)

Antcliffe, Jonathan B; Callow, Richard H T; Brasier, Martin D

2014-11-01

Twenty candidate fossils with claim to be the oldest representative of the Phylum Porifera have been re-analysed. Three criteria are used to assess each candidate: (i) the diagnostic criteria needed to categorize sponges in the fossil record; (ii) the presence, or absence, of such diagnostic features in the putative poriferan fossils; and (iii) the age constraints for the candidate fossils. All three criteria are critical to the correct interpretation of any fossil and its placement within an evolutionary context. Our analysis shows that no Precambrian fossil candidate yet satisfies all three of these criteria to be a reliable sponge fossil. The oldest widely accepted candidate, Mongolian silica hexacts from c. 545 million years ago (Ma), are here shown to be cruciform arsenopyrite crystals. The oldest reliable sponge remains are siliceous spicules from the basal Cambrian (Protohertzina anabarica Zone) Soltanieh Formation, Iran, which are described and analysed here in detail for the first time. Extensive archaeocyathan sponge reefs emerge and radiate as late as the middle of the Fortunian Stage of the Cambrian and demonstrate a gradual assembly of their skeletal structure through this time coincident with the evolution of other metazoan groups. Since the Porifera are basal in the Metazoa, their presence within the late Proterozoic has been widely anticipated. Molecular clock calibration for the earliest Porifera and Metazoa should now be based on the Iranian hexactinellid material dated to c. 535 Ma. The earliest convincing fossil sponge remains appeared at around the time of the Precambrian-Cambrian boundary, associated with the great radiation events of that interval. © 2014 The Authors. Biological Reviews © 2014 Cambridge Philosophical Society.

Fossil Energy Advanced Research and Technology Development (AR&TD) Materials Program semiannual progress report for the period ending September 30, 1991. Fossil Energy Program

Energy Technology Data Exchange (ETDEWEB)

Judkins, R.R.; Cole, N.C. [comps.

1992-04-01

The objective of the Fossil Energy Advanced Research and Technology Development Materials Program is to conduct research and development on materials for fossil energy applications with a focus on the longer-term and generic needs of the various fossil fuel technologies. The Program includes research aimed toward a better understanding of materials behavior in fossil energy environments and the development of new materials capable of substantial enhancement of plant operations and reliability. Research is outlined in four areas: Ceramics, New Alloys, Corrosion and Erosion Research, and Technology Development and Transfer. (VC)

Implications for global energy markets: implications for non-fossil energy sources

International Nuclear Information System (INIS)

Grubb, Michael

1998-01-01

This paper highlights the recent developments concerning non-fossil energy and examines the impact of the Kyoto Protocol on non-fossil energy sources, and the implications for non-fossil sources in the implementation of the Kyoto Protocol. The current contributions of fossil and non-fossil fuels to electricity production, prospects for expansion of the established non-fossil sources, new renewables in Europe to date, renewables in Europe to 2010, and policy integration in the EU are discussed. Charts illustrating the generating capacity of renewable energy plant in Britain (1992-1966), wind energy capacity in Europe (1990-2000), and projected renewable energy contributions in the EU (wind, small hydro, photovoltaic, biomass and geothermal) are provided. (UK)

The Fossil Calibration Database-A New Resource for Divergence Dating.

Science.gov (United States)

Ksepka, Daniel T; Parham, James F; Allman, James F; Benton, Michael J; Carrano, Matthew T; Cranston, Karen A; Donoghue, Philip C J; Head, Jason J; Hermsen, Elizabeth J; Irmis, Randall B; Joyce, Walter G; Kohli, Manpreet; Lamm, Kristin D; Leehr, Dan; Patané, Josés L; Polly, P David; Phillips, Matthew J; Smith, N Adam; Smith, Nathan D; Van Tuinen, Marcel; Ware, Jessica L; Warnock, Rachel C M

2015-09-01

Fossils provide the principal basis for temporal calibrations, which are critical to the accuracy of divergence dating analyses. Translating fossil data into minimum and maximum bounds for calibrations is the most important-often least appreciated-step of divergence dating. Properly justified calibrations require the synthesis of phylogenetic, paleontological, and geological evidence and can be difficult for nonspecialists to formulate. The dynamic nature of the fossil record (e.g., new discoveries, taxonomic revisions, updates of global or local stratigraphy) requires that calibration data be updated continually lest they become obsolete. Here, we announce the Fossil Calibration Database (http://fossilcalibrations.org), a new open-access resource providing vetted fossil calibrations to the scientific community. Calibrations accessioned into this database are based on individual fossil specimens and follow best practices for phylogenetic justification and geochronological constraint. The associated Fossil Calibration Series, a calibration-themed publication series at Palaeontologia Electronica, will serve as a key pipeline for peer-reviewed calibrations to enter the database. © The Author(s) 2015. Published by Oxford University Press, on behalf of the Society of Systematic Biologists. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

The energy challenge of a post-fossil world: Seasonal energy storage

International Nuclear Information System (INIS)

Forsberg, C.

2009-01-01

Fossil fuels are an energy source and an energy storage system. The demand for electricity and heat varies daily, weekly, and seasonally with seasonal variations often varying by a factor of two or more. The variable demand is met by fossil fuels because 1) fossil fuels are inexpensive to store in coal piles, oil tanks, and underground natural gas storage facilities and 2) the capital cost of the equipment to burn fossil fuels and convert the energy to heat or electricity is small relative to the cost of the fossil fuels. Concerns about climate change may limit the conventional use of fossil fuels. The alternative low-carbon energy production systems (nuclear, fossil fuels with carbon dioxide sequestration, wind, and solar) are capital-intensive energy sources with low operating costs. To obtain favorable economics these technologies must operate at full capacity; but, their output does not match energy demand. We have energy alternatives to fossil fuels but no replacements for the energy storage capabilities or fossil fuels. Proposed strategies and technologies to address the grand storage challenge (including seasonal storage of electricity) are described. The options suggest a nuclear-renewable future to address seasonal energy storage needs in a low-carbon world.

When will fossil fuel reserves be diminished?

International Nuclear Information System (INIS)

Shafiee, Shahriar; Topal, Erkan

2009-01-01

Crude oil, coal and gas are the main resources for world energy supply. The size of fossil fuel reserves and the dilemma that 'when non-renewable energy will be diminished' is a fundamental and doubtful question that needs to be answered. This paper presents a new formula for calculating when fossil fuel reserves are likely to be depleted and develops an econometrics model to demonstrate the relationship between fossil fuel reserves and some main variables. The new formula is modified from the Klass model and thus assumes a continuous compound rate and computes fossil fuel reserve depletion times for oil, coal and gas of approximately 35, 107 and 37 years, respectively. This means that coal reserves are available up to 2112, and will be the only fossil fuel remaining after 2042. In the Econometrics model, the main exogenous variables affecting oil, coal and gas reserve trends are their consumption and respective prices between 1980 and 2006. The models for oil and gas reserves unexpectedly show a positive and significant relationship with consumption, while presenting a negative and significant relationship with price. The econometrics model for coal reserves, however, expectedly illustrates a negative and significant relationship with consumption and a positive and significant relationship with price. Consequently, huge reserves of coal and low-level coal prices in comparison to oil and gas make coal one of the main energy substitutions for oil and gas in the future, under the assumption of coal as a clean energy source

Impact of urine preservation methods and duration of storage on measured levels of environmental contaminants.

Science.gov (United States)

Hoppin, Jane A; Ulmer, Ross; Calafat, Antonia M; Barr, Dana B; Baker, Susan V; Meltzer, Helle M; Rønningen, Kjersti S

2006-01-01

Collection of urine samples in human studies involves choices regarding shipping, sample preservation, and storage that may ultimately influence future analysis. As more studies collect and archive urine samples to evaluate environmental exposures in the future, we were interested in assessing the impact of urine preservative, storage temperature, and time since collection on nonpersistent contaminants in urine samples. In spiked urine samples stored in three types of urine vacutainers (no preservative, boric acid, and chlorhexidine), we measured five groups of contaminants to assess the levels of these analytes at five time points (0, 24, 48, and 72 h, and 1 week) and at two temperatures (room temperature and 4 degrees C). The target chemicals were bisphenol A (BPA), metabolites of organophosphate (OP), carbamate, and pyrethroid insecticides, chlorinated phenols, and phthalate monoesters, and were measured using five different mass spectrometry-based methods. Three samples were analyzed at each time point, with the exception of BPA. Repeated measures analysis of variance was used to evaluate effects of storage time, temperature, and preservative. Stability was summarized with percent change in mean concentration from time 0. In general, most analytes were stable under all conditions with changes in mean concentration over time, temperature, and preservative being generally less than 20%, with the exception of the OP metabolites in the presence of boric acid. The effect of storage temperature was less important than time since collection. The precision of the laboratory measurements was high allowing us to observe small differences, which may not be important when categorizing individuals into broader exposure groups.

Preliminary Micropaleontological Investigation of a Preserved, Late Pleistocene Cypress Forest on the Northern Gulf of Mexico Inner Shelf

Science.gov (United States)

Truong, J. T.; DeLong, K. L.; Bentley, S. J.; Xu, K.; Harley, G. L.; Reese, A.; Gonzalez, S.; Obelcz, J.; Caporaso, A.

2017-12-01

Exposed at the bottom of a trough 13 km offshore Orange Beach, AL on the Gulf of Mexico (GOM) shelf in 18 m water depth are exceptionally preserved in situ bald cypress (Taxodium distichum) stumps. Preserved seeds (T. distichum, Cephalanthus occidentalis, Hibiscus lasiocarpos, Liquidambar styraciflua) discovered in core catcher samples illustrate the exceptional preservation of the site. Woody debris samples have come back radiocarbon dead with an exception to samples located in the upper peat layer with 14C ages from 37,350-41,830 years BP. Optically stimulated luminescence and 14C dates, in combination with GOM eustatic sea level curves, suggest the forest was located 30 m above the paleoshoreline. How the forest remained preserved during subaerial exposure of the continental shelf through the Last Glacial Maximum lowstand until ensuing Holocene sea level transgression remains unknown. The R/V Coastal Profiler collected 7 vibracores from the study site in 2015 and an additional 11 in 2016. A single core (DF1) contains facies identified as the Holocene Mississippi-Alabama-Florida sand sheet, a transitional facies of interbedded sand and mud, and a basal floodplain facies in which the stumps reside. This study seeks to identify the location of the Pleistocene-Holocene unconformity and to assist in stratigraphy of the area. Foraminiferal assemblages found within the transitional facies are of a shallow marine environment that suggests Holocene in age. It is hypothesized that a pulse of sea level rise during Marine Isotope Stages 3-4 caused subsequent rapid aggradation of the paleovalley system allowing for preservation through >30 kyrs of subaerial exposure. One of the ultimate goals of this study is to serve as a guide for identification of other possible sites along the gulf coast.

A long-term view of worldwide fossil fuel prices

International Nuclear Information System (INIS)

Shafiee, Shahriar; Topal, Erkan

2010-01-01

This paper reviews a long-term trend of worldwide fossil fuel prices in the future by introducing a new method to forecast oil, natural gas and coal prices. The first section of this study analyses the global fossil fuel market and the historical trend of real and nominal fossil fuel prices from 1950 to 2008. Historical fossil fuel price analysis shows that coal prices are decreasing, while natural gas prices are increasing. The second section reviews previously available price modelling techniques and proposes a new comprehensive version of the long-term trend reverting jump and dip diffusion model. The third section uses the new model to forecast fossil fuel prices in nominal and real terms from 2009 to 2018. The new model follows the extrapolation of the historical sinusoidal trend of nominal and real fossil fuel prices. The historical trends show an increase in nominal/real oil and natural gas prices plus nominal coal prices, as well as a decrease in real coal prices. Furthermore, the new model forecasts that oil, natural gas and coal will stay in jump for the next couple of years and after that they will revert back to the long-term trend until 2018. (author)

Depletion of fossil fuels and anthropogenic climate change—A review

International Nuclear Information System (INIS)

Höök, Mikael; Tang, Xu

2013-01-01

Future scenarios with significant anthropogenic climate change also display large increases in world production of fossil fuels, the principal CO 2 emission source. Meanwhile, fossil fuel depletion has also been identified as a future challenge. This chapter reviews the connection between these two issues and concludes that limits to availability of fossil fuels will set a limit for mankind's ability to affect the climate. However, this limit is unclear as various studies have reached quite different conclusions regarding future atmospheric CO 2 concentrations caused by fossil fuel limitations. It is concluded that the current set of emission scenarios used by the IPCC and others is perforated by optimistic expectations on future fossil fuel production that are improbable or even unrealistic. The current situation, where climate models largely rely on emission scenarios detached from the reality of supply and its inherent problems are problematic. In fact, it may even mislead planners and politicians into making decisions that mitigate one problem but make the other one worse. It is important to understand that the fossil energy problem and the anthropogenic climate change problem are tightly connected and need to be treated as two interwoven challenges necessitating a holistic solution. - Highlights: ► Review of the development of emission scenarios. ► Survey of future fossil fuel trajectories used by the IPCC emission scenarios. ► Discussions on energy transitions in the light of oil depletion. ► Review of earlier studies of future climate change and fossil fuel limitations.

Renewables vs fossil fuels

Energy Technology Data Exchange (ETDEWEB)

Adams, K. (Energy Research and Development Corporation (Australia))

1992-01-01

The paper examines some of the factors which will influence the future mix of energy from fossil fuels and renewable sources in Australia. Aspects covered include: the present energy situation; impact of environmental issues; potential for renewable energy; motivators for change; and research and development. It is concluded that the future for fossil fuels and renewable energy is dependent on a number of complex factors, many of which are currently unknown. The key factor is economic viability and that will be influenced by a range of factors such as policies of the Australian and overseas governments in relation to pollution and environment protection (reflected in the cost of meeting such requirements), exploration and production costs (also influenced by government policies), availability of supply, rate of technological development and the size of export markets. 8 refs., 2 figs., 1 tab.

Miocene fossil plants from Bukpyeong Formation of Bukpyeong Basin in Donghae City, Gangwon-do Province, Korea and their palaeoenvironmental implications

Science.gov (United States)

Jeong, Eun Kyoung; Kim, Hyun Joo; Uemura, Kazuhiko; Kim, Kyungsik

2016-04-01

The Tertiary sedimentary basins are distributed along the eastern coast of Korean Peninsula. The northernmost Bukpyeong Basin is located in Donghae City, Gangwon-do Province, Korea. The Bukpyeong Basin consists of Bukpyeong Formation and Dogyeongri Conglomerate in ascending order. The geologic age of Bukpyeong Formation has been suggested as from Early Miocene to Pliocene, In particular, Lee & Jacobs (2010) suggested the age of the Bukpyeong Formation as late Early Miocene to early Middle Miocene based on the fossils of rodent teeth. Sedimentary environment has been thought as mainly fresh water lake and/or swamp partly influenced by marine water. Lately, new outcrops of Bukpyeong Formation were exposed during the road construction and abundant fossil plants were yielded from the newly exposed outcrops. As a result of palaeobotanical studies 47 genera of 23 families have been found. This fossil plant assemblage is composed of gymnosperms and dicotyledons. Gymnosperms were Pinaceae (e.g., Pinus, Tsuga), Sciadopityaceae (e.g., Sciadopitys) and Cupressaceae with well-preserved Metasequoia cones. Dicotyledons were deciduous trees such as Betulaceae (e.g., Alnus, Carpinus) and Sapindaceae (e.g., Acer, Aesculus, Sapindus), and evergreen trees such as evergreen Fagaceae (e.g., Castanopsis, Cyclobalanopsis, Pasania) and Lauraceae (e.g., Cinnamomum, Machilus). In addition, fresh water plants such as Hemitrapa (Lytraceae) and Ceratophyllum (Ceratophyllaceae) were also found. The fossil plant assemblage of the Bukpyeong Formation supported the freshwater environment implied by previous studies. It can be suggested that the palaeoflora of Bukpyeong Formation was oak-laurel forest with broad-leaved evergreen and deciduous trees accompanying commonly by conifers of Pinaceae and Cupressaceae under warm-temperate climate.

The financial impact of divestment from fossil fuels

NARCIS (Netherlands)

Plantinga, Auke; Scholtens, Bert

2016-01-01

Divesting from fossil companies has been put forward as a means to address climate change. We study the impact of such divesting on investment portfolio performance. To this extent, we systematically investigate the investment performance of portfolios with and without fossil fuel company stocks. We

Methane emissions and climate compatibility of fossil fuels

International Nuclear Information System (INIS)

Meier, B.

1992-01-01

Methane contributes directly and indirectly to the additional greenhouse effect caused by human activities. The vast majority of the anthropogenic methane release occurs worldwide in non-fossil sources such as rice cultivation, livestock operations, sanitary landfills and combustion of bio-mass. Methane emissions also occur during production, distribution and utilisation of fossil fuels. Also when considering the methane release and CO 2 -emissions of processes upstream of combustion, the ranking of environmental compatibility of natural gas, fuel oil and cool remains unchanged. Of all fossil fuels, natural gas contributes the least to the greenhouse effect. (orig.) [de

FIRST RECORD OF FOSSIL CYSTOPHORINAE (CARNIVORA, PHOCIDAE: MIDDLE MIOCENE SEALS FROM THE NORTHERN PARATETHYS

Directory of Open Access Journals (Sweden)

IRINA A. KORETSKY

2013-11-01

Full Text Available Despite a long history of phocid studies, no fossil members of the Subfamily Cystophorinae have ever been described. New fossil material from the Middle Sarmatian (11.2-12.3 Ma in the Paratethyan Basin of Ukraine allows emended diagnoses and redescriptions to help clarify phylogenetic relationships within the Family Phocidae. After cladistic and morphological analyses of the material, a new genus ( Pachyphoca  was erected, with two new species of extinct fossil true seals ( Pachyphoca ukrainica and Pachyphoca chapskii , belonging to the Subfamily Cystophorinae. This new material shows exceptional pachyosteosclerotic bones, which is uncommon for the family as a whole. The new Miocene genus shares numerous characters with several Recent species of Cystophora and Mirounga , providing the first opportunity to study sexual dimorphism of limb bones and mandibles in the Subfamily Cystophorinae. Sexual dimorphism in postcranial bones and mandibles in living members of Cystophorinae is more obvious than in other representatives of true seals. Examination of anatomical traits demonstrated that both new species are more primitive and better adapted for terrestrial locomotion than any living representatives of Cystophorinae. The smaller Pachyphoca ukrainica is more adapted to terrestrial locomotion than its larger relative, P . chapskii . Phylogenetic analysis suggests that seals with 10 incisors (Phocinae are more primitive than those with 8 (Monachinae, and that Monachinae are more primitive than seals with 6 incisors (Cystophorinae.These findings indicate that the Subfamily Cystophorinae includes not only elephant and hooded seals, but also the two new Middle Sarmatian pachyosteosclerotic seals. 

Problems related to fossil fuels utilization

International Nuclear Information System (INIS)

Rota, R.

1999-01-01

Fossil fuels still present the main energy source in the world since about 90% of the energy produced comes from combustion. This paper, based on the lectures given at the conference of Energy and Environment hold at the Accademia dei Lincei in 1998, presents a short review of some of the problems related to the utilization of fossil fuels, such as their availability in the medium period, the effect of pollutant dispersion in the atmosphere as well as the available technologies to deal with such problems [it

Geomicrobiological study of modern microbialites from Mexico: towards a better understanding of the ancient fossil record

Directory of Open Access Journals (Sweden)

Benzerara K.

2014-02-01

Full Text Available Microbialites are sedimentary formations that are found throughout the geological record and are usually considered as one of the oldest traces of life on Earth. Although they have been known for more than a century and hold as an emblematic object in Earth Sciences, we yet do not understand in details how they form and how microbial processes impact their chemistry, structure and macroscopic morphology. Here, we show recent advances achieved owing to funding provided by the EPOV program on the formation of modern microbialites in the crater Lake Alchichica (Mexico. We first show that very diverse microbial communities populate these microbialites, including diverse microbial groups able to induce carbonate precipitation. We demonstrate that this microbial diversity can be preserved for several years in laboratory aquaria offering a nice opportunity for future studies to assess the relationships between biodiversity and microbialite formation. We then detail the textural modifications affecting cyanobacterial cells during the first steps of fossilization as captured in Alchichica microbialites. Finally, we report the discovery of a new deepbranching cyanobacterium species, Candidatus Gloeomargarita lithophora, able to form intracellular Ca-, Mg-, Sr- and Ba-rich carbonates and discuss the implications for the interpretation of the fossil record.

Hydrogen as a renewable and sustainable solution in reducing global fossil fuel consumption

International Nuclear Information System (INIS)

Midilli, Adnan; Dincer, Ibrahim

2008-01-01

In this paper, hydrogen is considered as a renewable and sustainable solution for reducing global fossil fuel consumption and combating global warming and studied exergetically through a parametric performance analysis. The environmental impact results are then compared with the ones obtained for fossil fuels. In this regard, some exergetic expressions are derived depending primarily upon the exergetic utilization ratios of fossil fuels and hydrogen: the fossil fuel based global waste exergy factor, hydrogen based global exergetic efficiency, fossil fuel based global irreversibility coefficient and hydrogen based global exergetic indicator. These relations incorporate predicted exergetic utilization ratios for hydrogen energy from non-fossil fuel resources such as water, etc., and are used to investigate whether or not exergetic utilization of hydrogen can significantly reduce the fossil fuel based global irreversibility coefficient (ranging from 1 to +∞) indicating the fossil fuel consumption and contribute to increase the hydrogen based global exergetic indicator (ranging from 0 to 1) indicating the hydrogen utilization at a certain ratio of fossil fuel utilization. In order to verify all these exergetic expressions, the actual fossil fuel consumption and production data are taken from the literature. Due to the unavailability of appropriate hydrogen data for analysis, it is assumed that the utilization ratios of hydrogen are ranged between 0 and 1. For the verification of these parameters, the variations of fossil fuel based global irreversibility coefficient and hydrogen based global exergetic indicator as the functions of fossil fuel based global waste exergy factor, hydrogen based global exergetic efficiency and exergetic utilization of hydrogen from non-fossil fuels are analyzed and discussed in detail. Consequently, if exergetic utilization ratio of hydrogen from non-fossil fuel sources at a certain exergetic utilization ratio of fossil fuels increases

Fossil-Fuel C02 Emissions Database and Exploration System

Science.gov (United States)

Krassovski, M.; Boden, T.

2012-04-01

Fossil-Fuel C02 Emissions Database and Exploration System Misha Krassovski and Tom Boden Carbon Dioxide Information Analysis Center Oak Ridge National Laboratory The Carbon Dioxide Information Analysis Center (CDIAC) at Oak Ridge National Laboratory (ORNL) quantifies the release of carbon from fossil-fuel use and cement production each year at global, regional, and national spatial scales. These estimates are vital to climate change research given the strong evidence suggesting fossil-fuel emissions are responsible for unprecedented levels of carbon dioxide (CO2) in the atmosphere. The CDIAC fossil-fuel emissions time series are based largely on annual energy statistics published for all nations by the United Nations (UN). Publications containing historical energy statistics make it possible to estimate fossil-fuel CO2 emissions back to 1751 before the Industrial Revolution. From these core fossil-fuel CO2 emission time series, CDIAC has developed a number of additional data products to satisfy modeling needs and to address other questions aimed at improving our understanding of the global carbon cycle budget. For example, CDIAC also produces a time series of gridded fossil-fuel CO2 emission estimates and isotopic (e.g., C13) emissions estimates. The gridded data are generated using the methodology described in Andres et al. (2011) and provide monthly and annual estimates for 1751-2008 at 1° latitude by 1° longitude resolution. These gridded emission estimates are being used in the latest IPCC Scientific Assessment (AR4). Isotopic estimates are possible thanks to detailed information for individual nations regarding the carbon content of select fuels (e.g., the carbon signature of natural gas from Russia). CDIAC has recently developed a relational database to house these baseline emissions estimates and associated derived products and a web-based interface to help users worldwide query these data holdings. Users can identify, explore and download desired CDIAC

Financial subsidies to the Australian fossil fuel industry

International Nuclear Information System (INIS)

Riedy, Chris; Diesendorf, Mark

2003-01-01

A common claim during international greenhouse gas reduction negotiations has been that domestic emissions cuts will harm national economies. This argument fails to consider the distorting effect of existing financial subsidies and associated incentives to fossil fuel production and consumption provided by governments in most developed countries. These subsidies support a fossil fuel energy sector that is the major contributor to global greenhouse gas emissions and conflict with attempts to expand the role of sustainable energy technologies. Reform of these types of subsidies has the potential to provide substantial gains in economic efficiency as well as reductions in carbon dioxide emissions--a 'no regrets' outcome for the economy and the environment. This paper examines financial subsidies to fossil fuel production and consumption in Australia and estimates the magnitude of the subsidies. Subsidies and associated incentives to fossil fuel production and consumption in Australia are similar to those in the United States and the other countries that have pushed for increased 'flexibility' during international negotiations

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.

News technology utilization fossil fuel

Directory of Open Access Journals (Sweden)

Blišanová Monika

2004-09-01

Full Text Available Fossil fuel – “alternative energy“ is coal, petroleum, natural gas. Petroleum and natural gas are scarce resources, but they are delimited. Reserves petroleum will be depleted after 39 years and reserves natural gas after 60 years.World reserves coal are good for another 240 years. Coal is the most abundant fossil fuel. It is the least expensive energy source for generating electricity. Many environmental problems associated with use of coal:in coal production, mining creates environmental problems.On Slovakia representative coal only important internal fuel – power of source and coal is produced in 5 locality. Nowadays, oneself invest to new technology on utilization coal. Perspective solution onself shows UCG, IGCC.

Water Use of Fossil Energy Production and Supply in China

Directory of Open Access Journals (Sweden)

Gang Lin

2017-07-01

Full Text Available Fossil energy and water resources are both important for economic and social development in China, and they are tightly interlinked. Fossil energy production consumes large amounts of water, and it is essential to investigate the water footprint of fossil energy production (WFEP in China. In addition, fossil energy is supplied to consumers in China by both domestic and foreign producers, and understanding the water footprint of fossil energy supply (WFES is also highly significant for water and energy development programs in the long-term. The objectives of this paper were to provide an estimation of the blue component of WFEP and WFES in China for the period from 2001 to 2014, and to evaluate the impact on water resources from energy production, the contribution of internal and external WFES, and water-energy related issues of the international energy trade by applying water footprint analysis based on the bottom-up approach. The results indicate that generally, the WFEP and WFES in China both maintained steady growth before 2013, with the WFEP increasing from approximately 3900 million m3/year to 10,400 million m3/year, while the WFES grew from 3900 million m3/year to 11,600 million m3/year. The fossil energy production caps of the 13th Five Year Plan can bring the water consumed for fossil energy production back to a sustainable level. Over the long-term, China’s energy trade plan should also consider the water and energy resources of the countries from which fossil energy is imported.

On the importance of stratigraphic control for vertebrate fossil sites in Channel Islands National Park, California, USA: Examples from new Mammuthus finds on San Miguel Island

Science.gov (United States)

Pigati, Jeffery S.; Muhs, Daniel R.; McGeehin, John P.

2016-01-01

Quaternary vertebrate fossils, most notably mammoth remains, are relatively common on the northern Channel Islands of California. Well-preserved cranial, dental, and appendicular elements of Mammuthus exilis (pygmy mammoth) and Mammuthus columbi (Columbian mammoth) have been recovered from hundreds of localities on the islands during the past half-century or more. Despite this paleontological wealth, the geologic context of the fossils is described in the published literature only briefly or not at all, which has hampered the interpretation of associated 14C ages and reconstruction of past environmental conditions. We recently discovered a partial tusk, several large bones, and a tooth enamel plate (all likely mammoth) at two sites on the northwest flank of San Miguel Island, California. At both localities, we documented the stratigraphic context of the fossils, described the host sediments in detail, and collected charcoal and terrestrial gastropod shells for radiocarbon dating. The resulting 14C ages indicate that the mammoths were present on San Miguel Island between ∼20 and 17 ka as well as between ∼14 and 13 ka (thousands of calibrated 14C years before present), similar to other mammoth sites on San Miguel, Santa Cruz, and Santa Rosa Islands. In addition to documenting the geologic context and ages of the fossils, we present a series of protocols for documenting and reporting geologic and stratigraphic information at fossil sites on the California Channel Islands in general, and in Channel Islands National Park in particular, so that pertinent information is collected prior to excavation of vertebrate materials, thus maximizing their scientific value.

Fossil evidence of wing shape in a stem relative of swifts and hummingbirds (Aves, Pan-Apodiformes).

Science.gov (United States)

Ksepka, Daniel T; Clarke, Julia A; Nesbitt, Sterling J; Kulp, Felicia B; Grande, Lance

2013-06-22

A feathered specimen of a new species of Eocypselus from the Early Eocene Green River Formation of Wyoming provides insight into the wing morphology and ecology in an early part of the lineage leading to extant swifts and hummingbirds. Combined phylogenetic analysis of morphological and molecular data supports placement of Eocypselus outside the crown radiation of Apodiformes. The new specimen is the first described fossil of Pan-Apodiformes from the pre-Pleistocene of North America and the only reported stem taxon with informative feather preservation. Wing morphology of Eocypselus rowei sp. nov. is intermediate between the short wings of hummingbirds and the hyper-elongated wings of extant swifts, and shows neither modifications for the continuous gliding used by swifts nor modifications for the hovering flight style used by hummingbirds. Elongate hindlimb elements, particularly the pedal phalanges, also support stronger perching capabilities than are present in Apodiformes. The new species is the smallest bird yet described from the Green River Formation, and supports the hypothesis that a decrease in body size preceded flight specializations in Pan-Apodiformes. The specimen also provides the first instance of melanosome morphology preserved in association with skeletal remains from the Green River Formation.

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

100 years of discovery of the Burgess Shale 1909-2009 : a celebration of the discovery of the world's most important fossils

Energy Technology Data Exchange (ETDEWEB)

NONE

2009-07-01

The centennial celebration of the discovery of the Burgess Shale consisted of informative science presentations to the general public. Scientific presenters also participated in guided hikes in Yoho National Park within the Canadian Rockies where the Burgess Shale can be found. The first Burgess Shale fossils were discovered in 1909 by Charles D. Walcott. Thousands of specimens have since been collected from the quarry named after him. The informative science presentations described the burst of biodiversity of marine plants and marine invertebrate animals that lived in a shallow sea in the vicinity of a massive carbonate reef during the Cambrian Period. They described the unusual conditions that allowed for the very rare preservation of the animals in the Burgess Shale. The Burgess Shale fossils merit special interest because they reveal how animal life appeared on Earth better than any other fossil record. In addition to the geological history of the Burgess Shale area, the centennial lectures also addressed topics such as climate and the geological record of climate change; the influence of continental drift on evolution; and fluid geochemistry in the Western Canada Foreland Basin and paleoclimate influence. The Burgess Shale was designated a UNESCO World Heritage Site in 1981 as it provides key information about evolution of life on Earth. refs. figs.

Fossil resource trade balances. Emerging trends for the UK

International Nuclear Information System (INIS)

Papathanasopoulou, Eleni; Jackson, Tim

2008-01-01

The aim of this paper is to examine the extent to which the UK can be classified as a net importer of fossil resources and a creator of pollution havens abroad between 1968 and 2000. Using input-output techniques and a derived Resource Flow Classification System, both the physical trade balance (PTB) and pollution trade balance (UTB) associated with fossil resource use are computed. The PTB shows that between 1968 and the early 1980's the UK is presented as a net importer of direct fossil resource flows. Between 1984 and 2000, the UK is identified as a net exporter of direct fossil resources. These trends are primarily explained by the UK's discovery and commercial production of North Sea oil and gas fields in the late 1970s. On the other hand, the UTB shows that over the whole period the indirect used flows attributable to the UK's exports are higher than those attributable to its imports. These findings suggest that the UK did not create pollution havens abroad from the use of fossil resources between 1968 and 2000. However, it is noticeable in both cases that from 1995 the UK's position as a net exporter has been decreasing considerably. Maturing North Sea oil and gas fields set against increasing demands for fossil fuels and imported goods is signalling a return to the UK's pre-1984 dependence on direct imported fossil resources and the possible creation of pollution havens abroad. Knowledge of these trends contributes to the evidence base for the UK's changing import and export structure and the potential environmental repercussions at home and abroad. (author)

Fossil resource trade balances. Emerging trends for the UK

Energy Technology Data Exchange (ETDEWEB)

Papathanasopoulou, Eleni; Jackson, Tim [Centre for Environmental Strategy, University of Surrey, Guildford, Surrey, GU2 7TH (United Kingdom)

2008-06-15

The aim of this paper is to examine the extent to which the UK can be classified as a net importer of fossil resources and a creator of pollution havens abroad between 1968 and 2000. Using input-output techniques and a derived Resource Flow Classification System, both the physical trade balance (PTB) and pollution trade balance (UTB) associated with fossil resource use are computed. The PTB shows that between 1968 and the early 1980's the UK is presented as a net importer of direct fossil resource flows. Between 1984 and 2000, the UK is identified as a net exporter of direct fossil resources. These trends are primarily explained by the UK's discovery and commercial production of North Sea oil and gas fields in the late 1970s. On the other hand, the UTB shows that over the whole period the indirect used flows attributable to the UK's exports are higher than those attributable to its imports. These findings suggest that the UK did not create pollution havens abroad from the use of fossil resources between 1968 and 2000. However, it is noticeable in both cases that from 1995 the UK's position as a net exporter has been decreasing considerably. Maturing North Sea oil and gas fields set against increasing demands for fossil fuels and imported goods is signalling a return to the UK's pre-1984 dependence on direct imported fossil resources and the possible creation of pollution havens abroad. Knowledge of these trends contributes to the evidence base for the UK's changing import and export structure and the potential environmental repercussions at home and abroad. (author)

Analysis of radiation level on dinosaur fossil in Zigong

International Nuclear Information System (INIS)

Yang Changshu; Liang Shuzhi; Fan Zhengnian.

1995-01-01

Study on radiation level of dinosaur fossil and environment in conservation zone in Zigong, Sichuan has been done. The results showed that the γ radiation dose and radioactivity strength of 232 Th and 40 K in dinosaur fossil, soil and rock in the conservation zone were within the limits of radioactive background value in Zigong. Radioactivity strength of 238 U, 226 Ra in dinosaur fossil were 26.6 and 29.2 times higher than the rock of same layer respectively

Total-Evidence Dating under the Fossilized Birth-Death Process.

Science.gov (United States)

Zhang, Chi; Stadler, Tanja; Klopfstein, Seraina; Heath, Tracy A; Ronquist, Fredrik

2016-03-01

Bayesian total-evidence dating involves the simultaneous analysis of morphological data from the fossil record and morphological and sequence data from recent organisms, and it accommodates the uncertainty in the placement of fossils while dating the phylogenetic tree. Due to the flexibility of the Bayesian approach, total-evidence dating can also incorporate additional sources of information. Here, we take advantage of this and expand the analysis to include information about fossilization and sampling processes. Our work is based on the recently described fossilized birth-death (FBD) process, which has been used to model speciation, extinction, and fossilization rates that can vary over time in a piecewise manner. So far, sampling of extant and fossil taxa has been assumed to be either complete or uniformly at random, an assumption which is only valid for a minority of data sets. We therefore extend the FBD process to accommodate diversified sampling of extant taxa, which is standard practice in studies of higher-level taxa. We verify the implementation using simulations and apply it to the early radiation of Hymenoptera (wasps, ants, and bees). Previous total-evidence dating analyses of this data set were based on a simple uniform tree prior and dated the initial radiation of extant Hymenoptera to the late Carboniferous (309 Ma). The analyses using the FBD prior under diversified sampling, however, date the radiation to the Triassic and Permian (252 Ma), slightly older than the age of the oldest hymenopteran fossils. By exploring a variety of FBD model assumptions, we show that it is mainly the accommodation of diversified sampling that causes the push toward more recent divergence times. Accounting for diversified sampling thus has the potential to close the long-discussed gap between rocks and clocks. We conclude that the explicit modeling of fossilization and sampling processes can improve divergence time estimates, but only if all important model aspects

Preliminary study of coconut water for graft tissues preservation in transplantation.

Science.gov (United States)

César, Jorge Miguel Schettino; Petroianu, Andy; Vasconcelos, Leonardo de Souza; Cardoso, Valbert Nascimento; Mota, Luciene das Graças; Barbosa, Alfredo José Afonso; Soares, Cristina Duarte Vianna; de Oliveira, Amanda Lima

2015-01-01

to verify the effectiveness of coconut water in preserving tissues for transplant. Fifty male Wistar rats were randomly distributed in five groups, according to the following preservation solutions for tissue grafts: Group 1: Lactated Ringer; Group 2: Belzer solution; Group 3: mature coconut water; Group 4: green coconut water; Group 5: modified coconut water. In Group 5, the green coconut water has been modified like the Belzer solution. From each animal we harvested the spleen, ovaries and skin of the back segment. These tissues were preserved for six hours in one of the solutions. Then, the grafts were reimplanted. The recovery of the function of the implanted tissues was assessed 90 days after surgery, by splenic scintigraphy and blood exam. The implanted tissues were collected for histopathological examination. The serum levels did not differ among groups, except for the animals in Group 5, which showed higher levels of IgG than Group 1, and differences in relation to FSH between groups 1 and 2 (p coconut water (p coconut water-based solutions preserves spleen, ovary, and rat skin for six hours, maintaining their normal function.

Fossil intermediate-depth earthquakes in subducting slabs linked to differential stress release

Science.gov (United States)

Scambelluri, Marco; Pennacchioni, Giorgio; Gilio, Mattia; Bestmann, Michel; Plümper, Oliver; Nestola, Fabrizio

2017-12-01

The cause of intermediate-depth (50-300 km) seismicity in subduction zones is uncertain. It is typically attributed either to rock embrittlement associated with fluid pressurization, or to thermal runaway instabilities. Here we document glassy pseudotachylyte fault rocks—the products of frictional melting during coseismic faulting—in the Lanzo Massif ophiolite in the Italian Western Alps. These pseudotachylytes formed at subduction-zone depths of 60-70 km in poorly hydrated to dry oceanic gabbro and mantle peridotite. This rock suite is a fossil analogue to an oceanic lithospheric mantle that undergoes present-day subduction. The pseudotachylytes locally preserve high-pressure minerals that indicate an intermediate-depth seismic environment. These pseudotachylytes are important because they are hosted in a near-anhydrous lithosphere free of coeval ductile deformation, which excludes an origin by dehydration embrittlement or thermal runaway processes. Instead, our observations indicate that seismicity in cold subducting slabs can be explained by the release of differential stresses accumulated in strong dry metastable rocks.

Comprehensive geobiological characterization of a bituminous carbonate facies with Ediacara-type fossils (Shibantan Member, South China)

Science.gov (United States)

Duda, Jan-Peter; Blumenberg, Martin; Thiel, Volker; Simon, Klaus; Zhu, Maoyan; Reitner, Joachim

2015-04-01

�13C = -31.7 to -36.3o VPDB) indicate a significant withdrawal of 12C by primary producers that thrived within the microbial mats. At the same time, sulphurised biomarkers in the bitumen and HyPy-treated extraction residue hint at organic matter decomposition and concomitant sulphide production by sulphate-reducing bacteria. Given the sedimentological evidence for periodical ventilation of the water column by storms, sulphide oxidising bacteria were possibly favoured whenever oxygen became available at the sediment-water interface. Taken together, the environments in which the microbial-mat-associated biota including Ediacara-type fossils throve were highly dynamic due to a complex interplay of geological and biological processes. References Chen Z., Zhou C., Xiao S., Wang W., Guan C., Hua H., Yuan X., 2014. New Ediacara fossils preserved in marine limestone and their ecological implications. Scientific Reports, 4 Ding Q. and Chen Y., 1981. Discovery of soft metazoan from the Sinian System along eastern Yangtze Gorge, Hubei. Journal of the Wuhan College of Geology, 2, 53-57. Shen, B., Xiao S., Zhou C., Yuan X., 2009. Yangtziramulus zhangi New Genus and Species, a Carbonate-Hosted Macrofossil from the Ediacaran Dengying Formation in the Yangtze Gorges Area, South China. Journal of Paleontology, 83(4): 575-587. Sun W., 1986. Late precambrian pennatulids (sea pens) from the eastern Yangtze Gorge, China: Paracharnia gen. nov. Precambrian Research, 31(4), 361-375. Xiao S., Shen B., Zhou C., Xie G., Yuan X., 2005. A uniquely preserved Ediacaran fossil with direct evidence for a quilted bodyplan. Proceedings of the National Academy of Sciences of the United States of America, 102(29), 10227-10232.

Diagnosing Homo sapiens in the fossil record.

Science.gov (United States)

Stringer, Christopher Brian; Buck, Laura Tabitha

2014-01-01

Diagnosing Homo sapiens is a critical question in the study of human evolution. Although what constitutes living members of our own species is straightforward, in the fossil record this is still a matter of much debate. The issue is complicated by questions of species diagnoses and ideas about the mode by which a new species is born, by the arguments surrounding the behavioural and cognitive separateness of the species, by the increasing appreciation of variation in the early African H. sapiens record and by new DNA evidence of hybridization with extinct species. This study synthesizes thinking on the fossils, archaeology and underlying evolutionary models of the last several decades with recent DNA results from both H. sapiens and fossil species. It is concluded that, although it may not be possible or even desirable to cleanly partition out a homogenous morphological description of recent H. sapiens in the fossil record, there are key, distinguishing morphological traits in the cranium, dentition and pelvis that can be usefully employed to diagnose the H. sapiens lineage. Increasing advances in retrieving and understanding relevant genetic data provide a complementary and perhaps potentially even more fruitful means of characterizing the differences between H. sapiens and its close relatives.

Revised stratigraphy of Area 123, Koobi Fora, Kenya, and new age estimates of its fossil mammals, including hominins.

Science.gov (United States)

Gathogo, Patrick N; Brown, Francis H

2006-11-01

Recent geologic study shows that all hominins and nearly all other published mammalian fossils from Paleontological Collection Area 123, Koobi Fora, Kenya, derive from levels between the KBS Tuff (1.87+/-0.02 Ma) and the Lower Ileret Tuff (1.53+/-0.01 Ma). More specifically, the fossils derive from 53 m of section below the Lower Ileret Tuff, an interval in which beds vary markedly laterally, especially those units containing molluscs and algal stromatolites. The upper Burgi Member (approximately 2.00-1.87 Ma) crops out only in the southwestern part of Area 123. Adjacent Area 110 contains larger exposures of the member, and there the KBS Tuff is preserved as an airfall ash in lacustrine deposits and also as a fluvially redeposited ash. We observed no mammalian fossils in situ in this member in Area 123, but surface specimens have been documented in some monographic treatments. Fossil hominins from Area 123 were attributed to strata above the KBS Tuff in the 1970s, but later they were assigned to strata below the KBS Tuff (now called the upper Burgi Member). This study definitively places the Area 123 hominins in the KBS Member. Most of these hominins are between 1.60 and 1.65 myr in age, but the youngest may date to only 1.53 Ma, and the oldest, to 1.75 Ma. All are 0.15-0.30 myr younger than previously estimated. The new age estimates, in conjunction with published taxonomic attributions of fossils, suggest that at least two species of Homo coexisted in the region along with A. boisei until at least 1.65 Ma. Comparison of crania KNM-ER 1813 and KNM-ER 1470, which were believed to be of comparable age, is at the focus of the debate over whether Homo habilis sensu lato is in fact composed of two species: Homo habilis and Homo rudolfensis. These two crania are separated in time by approximately 0.25 myr, and therefore, arguments for their conspecificity no longer need to confront the issue of unusually high contemporaneous variation within a single species.

Reforming fossil fuel prices in India: Dilemma of a developing economy

International Nuclear Information System (INIS)

Anand, Mukesh Kumar

2016-01-01

Over the period between 1990–1 and 2012–3, fossil fuel use on farms has risen and its indirect use in farming, particularly for non-energy purposes, is also growing. Consequently, both energy intensity and fossil fuel intensity are rising for Indian agriculture. But, these are declining for the aggregate Indian economy. Thus, revision of fossil fuel prices acquires greater significance for Indian agriculture than for rest of the economy. There are significant differences across crops. The crop-level analysis is supplemented by an alternative approach that utilizes a three-sector input–output (I–O) model for the Indian economy representing farming, fossil fuels, and rest of economy. Fossil fuels sector is assessed to portray, in general, strong forward linkages. The increase in total cost of farming, for a given change in fossil fuel prices, is estimated as a multiple of increase in direct input cost of fossil fuels in farming. From the three-sector aggregated economy this multiple was estimated at 3.99 for 1998–9. But it grew to 6.7 in 2007–8. The findings have stronger ramifications than commonly recognized, for inflation and cost of implementing the policy on food security. - Highlights: •Fossil fuels’ contribution in primary energy supply has risen from 55 to 75 per cent. •Energy intensity halved for aggregate GDP, but doubled for agricultural GDP. •Impact of fossil fuel price increase on farming costs mimics a widening spiral. •Total cost of farming may increase 6.7 times the increase in direct fuel input cost.

Association of anatase (TiO2) and microbes: unusual fossilization effect or a potential biosignature?

Science.gov (United States)

Glamoclija, Mihaela; Andrew Steele,; Marc Fries,; Juergen Schieber,; Voytek, Mary A.; Charles S. Cockell,

2015-01-01

We combined microbial paleontology and molecular biology methods to study the Eyreville B drill core from the 35.3-Ma-old Chesapeake Bay impact structure,Virginia, USA. The investigated sample is a pyrite vein collected from the 1353.81-1353.89 m depth interval, located within a section of biotite granite. The granite is a pre-impact rock that was disrupted by the impact event. A search for inorganic (mineral) biosignatures revealed the presence of micron-size rod morphologies of anatase (TiO2) embedded in chlorite coatings on pyrite grains. Neither the Acridine Orange microbial probe nor deoxyribonucleic acid (DNA) extraction followed by polymerase chain reaction (PCR) amplifi cation showed the presence of DNA or ribonucleic acid (RNA) at the location of anatase rods, implying the absence of viable cells in the investigated area. A Nile Red microbial probe revealed the presence of lipids in the rods. Because most of the lipids are resistant over geologic time spans, they are good biomarkers, and they are an indicator of biogenicity for these possibly 35-Ma-old microbial fossils. The mineral assemblage suggests that rod morphologies are associated with low-temperature (<100 °C) hydrothermal alteration that involved aqueous fl uids. The temporal constraints on the anatase fossils are still uncertain because pre-impact alteration of the granite and postimpact heating may have provided identical conditions for anatase precipitation and microbial preservation.

Fossil plants from Romanian deposits of Bacles, Dolj District, Romania

Directory of Open Access Journals (Sweden)

Nicolae T̡icleanu

2001-09-01

Full Text Available From the Middle Romanian lacustrine deposits of the Oltenia province, the authors describe the youngest fossil flora known until now in Oltenia. The inventory of the fossil flora includes the following taxa: Taxodium dubium, ?Platanus platanifolia, Ulmus laevis, Quercus roburoides, Q. cf. muehlenbergii, Carya serraefolia, Acer cf. tricuspidatum and Salix sp. In the Bâcleş fossil flora, Glyptostrobus europaeus, which is a thermophilous and shows a high frequency in all Oltenia area till the XV-th coal seam, is absent. Consequently, having in view the high frequency of Taxodium dubium, which indicate temperate climate conditions, the other consider that the fossil flora from Bâcleş is much more younger and marks an important cooling. From palaeofloristic point of view, the study of Bâcleş fossil flora is indicative for river meadow forest and, probably, flat plain forest environments.

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.

Instrumentation and control for fossil-energy processes

Energy Technology Data Exchange (ETDEWEB)

1982-09-01

The 1982 symposium on instrumentation and control for fossil energy processes was held June 7 through 9, 1982, at Adam's Mark Hotel, Houston, Texas. It was sponsored by the US Department of Energy, Office of Fossil Energy; Argonne National Laboratory; and the Society for Control and Instrumentation of Energy Processes. Fifty-two papers have been entered individually into EDB and ERA; eleven papers had been entered previously from other sources. (LTN)

Comparison of Tissue Preservation using Formalin and Ethanol as Preservative Formula

OpenAIRE

See Woan Shian; Arifin Soenggono; Sawkar Vijay Pramod

2016-01-01

Background: Tissue preservation can be performed through embalming, by providing the chemical embalming fluid to the human remains. Formalin’s preservative formula is the foundation for modern methods of embalming. Unfortunately, this preservative formula has several disadvantages. While Ethanol’s preservative formula is a considerable agent to replace formalin’s preservative formula. The aim of this study was to compare the tissue preservation using formalin and ethanol as preservative formu...

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.)

Changes to the Fossil Record of Insects through Fifteen Years of Discovery

Science.gov (United States)

Nicholson, David B.; Mayhew, Peter J.; Ross, Andrew J.

2015-01-01

The first and last occurrences of hexapod families in the fossil record are compiled from publications up to end-2009. The major features of these data are compared with those of previous datasets (1993 and 1994). About a third of families (>400) are new to the fossil record since 1994, over half of the earlier, existing families have experienced changes in their known stratigraphic range and only about ten percent have unchanged ranges. Despite these significant additions to knowledge, the broad pattern of described richness through time remains similar, with described richness increasing steadily through geological history and a shift in dominant taxa, from Palaeoptera and Polyneoptera to Paraneoptera and Holometabola, after the Palaeozoic. However, after detrending, described richness is not well correlated with the earlier datasets, indicating significant changes in shorter-term patterns. There is reduced Palaeozoic richness, peaking at a different time, and a less pronounced Permian decline. A pronounced Triassic peak and decline is shown, and the plateau from the mid Early Cretaceous to the end of the period remains, albeit at substantially higher richness compared to earlier datasets. Origination and extinction rates are broadly similar to before, with a broad decline in both through time but episodic peaks, including end-Permian turnover. Origination more consistently exceeds extinction compared to previous datasets and exceptions are mainly in the Palaeozoic. These changes suggest that some inferences about causal mechanisms in insect macroevolution are likely to differ as well. PMID:26176667

Changes to the Fossil Record of Insects through Fifteen Years of Discovery.

Directory of Open Access Journals (Sweden)

David B Nicholson

Full Text Available The first and last occurrences of hexapod families in the fossil record are compiled from publications up to end-2009. The major features of these data are compared with those of previous datasets (1993 and 1994. About a third of families (>400 are new to the fossil record since 1994, over half of the earlier, existing families have experienced changes in their known stratigraphic range and only about ten percent have unchanged ranges. Despite these significant additions to knowledge, the broad pattern of described richness through time remains similar, with described richness increasing steadily through geological history and a shift in dominant taxa, from Palaeoptera and Polyneoptera to Paraneoptera and Holometabola, after the Palaeozoic. However, after detrending, described richness is not well correlated with the earlier datasets, indicating significant changes in shorter-term patterns. There is reduced Palaeozoic richness, peaking at a different time, and a less pronounced Permian decline. A pronounced Triassic peak and decline is shown, and the plateau from the mid Early Cretaceous to the end of the period remains, albeit at substantially higher richness compared to earlier datasets. Origination and extinction rates are broadly similar to before, with a broad decline in both through time but episodic peaks, including end-Permian turnover. Origination more consistently exceeds extinction compared to previous datasets and exceptions are mainly in the Palaeozoic. These changes suggest that some inferences about causal mechanisms in insect macroevolution are likely to differ as well.

Fossil human remains from Bolomor Cave (Valencia, Spain).

Science.gov (United States)

Arsuaga, Juan Luis; Fernández Peris, Josep; Gracia-Téllez, Ana; Quam, Rolf; Carretero, José Miguel; Barciela González, Virginia; Blasco, Ruth; Cuartero, Felipe; Sañudo, Pablo

2012-05-01

Systematic excavations carried out since 1989 at Bolomor Cave have led to the recovery of four Pleistocene human fossil remains, consisting of a fibular fragment, two isolated teeth, and a nearly complete adult parietal bone. All of these specimens date to the late Middle and early Late Pleistocene (MIS 7-5e). The fibular fragment shows thick cortical bone, an archaic feature found in non-modern (i.e. non-Homo sapiens) members of the genus Homo. Among the dental remains, the lack of a midtrigonid crest in the M(1) represents a departure from the morphology reported for the majority of Neandertal specimens, while the large dimensions and pronounced shoveling of the marginal ridges in the C(1) are similar to other European Middle and late Pleistocene fossils. The parietal bone is very thick, with dimensions that generally fall above Neandertal fossils and resemble more closely the Middle Pleistocene Atapuerca (SH) adult specimens. Based on the presence of archaic features, all the fossils from Bolomor are attributed to the Neandertal evolutionary lineage. Copyright © 2012 Elsevier Ltd. All rights reserved.

Bioenergy yield from cultivated land in Denmark - competition between food, bioenergy and fossil fuels under physical and environmental constraints

Energy Technology Data Exchange (ETDEWEB)

Callesen, I.; OEstergaard, H. (Technical Univ. of Denmark, Risoe National Lab. for Sustainable Energy. Biosystems Div., Roskilde (Denmark)); Grohnheit, P.E. (Technical Univ. of Denmark, Risoe National Lab. for Sustainable Energy. Systems Analysis Div., Roskilde (Denmark))

2011-07-15

area distributions, except the model optimized with oil index 25. In contrast, no land was allocated for bioenergy from oil seed rape and sugar beet cultivation at oil prices below oil index 170. The analysis shows that the potential for replacing fossil energy with bioenergy is lower than 19% of the primary energy demand if the bioenergy is based on domestic biomass production. A further increase in the use of bioenergy relies on import from world market supplies. (Author)

Preliminary study of coconut water for graft tissues preservation in transplantation

Directory of Open Access Journals (Sweden)

Jorge Miguel Schettino César

Full Text Available OBJECTIVE: to verify the effectiveness of coconut water in preserving tissues for transplant. METHODS: Fifty male Wistar rats were randomly distributed in five groups, according to the following preservation solutions for tissue grafts: Group 1: Lactated Ringer; Group 2: Belzer solution; Group 3: mature coconut water; Group 4: green coconut water; Group 5: modified coconut water. In Group 5, the green coconut water has been modified like the Belzer solution. From each animal we harvasted the spleen, ovaries and skin of the back segment. These tissues were preserved for six hours in one of the solutions. Then, the grafts were reimplanted. The recovery of the function of the implanted tissues was assessed 90 days after surgery, by splenic scintigraphy and blood exame. The implanted tissues were collected for histopathological examination. RESULTS: The serum levels did not differ among groups, except for the animals in Group 5, which showed higher levels of IgG than Group 1, and differences in relation to FSH between groups 1 and 2 (p <0.001, 4 and 2 (p = 0.03 and 5 and 2 (p = 0.01. The splenic scintigraphy was not different between groups. The ovarian tissue was better preserved in mature coconut water (p <0.007. CONCLUSION: the coconut water-based solutions preserves spleen, ovary, and rat skin for six hours, maintaining their normal function.

ESR dating studies on fossil of elaphurus davidianus horn

International Nuclear Information System (INIS)

Chen Shiming; Wang Hong; Tang Jingjuan; Yan Xiaomin; Guo Shiqing

1991-01-01

On the basis of studies on elephant tooth fossil, ESR dating of elaphurus davidianus horn fossil found in Anhui Province was reported. The sample examined by TEM electron spectrum is composed of hydroxyapatite. ESR experiments showed that the solid bone sample can be chosen as dating material. According to the contents of U, Th and K in the sample determined by ICP, the annual dose of radiation was calculated by using the linear uranium accumulation model and disequilibrium decay. The age of this fossil was determined to be 2.5 x 10 4 years

Fossil Energy Program annual progress report for April 1994 through March 1995

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-06-01

This report covers progress made during the period April 1, 1994, through March 31, 1995, 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, and DOE Morgantown Energy Technology Center, the DOE Pittsburgh Energy Technology Center, the DOE Fossil Energy Clean Coal Technology Program, the DOE Bartlesville Project Office, and the DOE Fossil Energy Office of Strategic Petroleum Reserve. The following research areas are covered in this report: Materials research and development; Environmental analysis support; Bioprocessing research; Coal combustion research; and Fossil fuels supplies modeling and research. Selected papers have been processed separately for inclusion in the Energy Science an Technology database.

The Fossil Fuel Divestment Movement: An Ethical Dilemma for the Geosciences?

Science.gov (United States)

Greene, C. H.; Kammen, D. M.

2014-12-01

For over 200 years, fossil fuels have been the basis for an industrial revolution that has delivered a level of prosperity to modern society unimaginable during the previous 5000 years of human civilization. However, society's dependence on fossil fuels is coming to an end for two reasons. The first reason is because our fossil fuel reserves are running out, oil in this century, natural gas during the next century, and coal a few centuries later. The second reason is because fossil fuels are having a devastating impact on the habitability of our planet, disrupting our climate system and acidifying our oceans. So the question is not whether we will discontinue using fossil fuels, but rather whether we will stop using them before they do irreparable damage to the Earth's life-support systems. Within our geoscience community, climate scientists have determined that a majority of existing fossil fuel reserves must remain unburned if dangerous climate change and ocean acidification are to be avoided. In contrast, Exxon-Mobil, Shell, and other members of the fossil fuel industry are pursuing a business model that assumes all of their reserves will be burned and will not become stranded assets. Since the geosciences have had a long and mutually beneficial relationship with the fossil fuel industry, this inherent conflict between climate science and industrial interests presents an ethical dilemma for many geoscientists. This conflict is further heightened by the fossil fuel divestment movement, which is underway at over 400 college and university campuses around the world. This presentation will explore some of the ethical and financial issues being raised by the divestment movement from a geoscientist's perspective.

Revisiting the origin and diversification of vascular plants through a comprehensive Bayesian analysis of the fossil record.

Science.gov (United States)

Silvestro, Daniele; Cascales-Miñana, Borja; Bacon, Christine D; Antonelli, Alexandre

2015-07-01

Plants have a long evolutionary history, during which mass extinction events dramatically affected Earth's ecosystems and its biodiversity. The fossil record can shed light on the diversification dynamics of plant life and reveal how changes in the origination-extinction balance have contributed to shaping the current flora. We use a novel Bayesian approach to estimate origination and extinction rates in plants throughout their history. We focus on the effect of the 'Big Five' mass extinctions and on estimating the timing of origin of vascular plants, seed plants and angiosperms. Our analyses show that plant diversification is characterized by several shifts in origination and extinction rates, often matching the most important geological boundaries. The estimated origin of major plant clades predates the oldest macrofossils when considering the uncertainties associated with the fossil record and the preservation process. Our findings show that the commonly recognized mass extinctions have affected each plant group differently and that phases of high extinction often coincided with major floral turnovers. For instance, after the Cretaceous-Paleogene boundary we infer negligible shifts in diversification of nonflowering seed plants, but find significantly decreased extinction in spore-bearing plants and increased origination rates in angiosperms, contributing to their current ecological and evolutionary dominance. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

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

A Middle Pennsylvanian (Bolsovian) peat-forming forest preserved in situ in volcanic ash of the Whetstone Horizon in the Radnice Basin, Czech Republic

OpenAIRE

Opluštil, Stanislav; Pšenicka, Josef; Libertín, Milan; Bashforth, Arden Roy; Šimunek, Zbynek; Drábková, Jana; Dašková, Jirina

2009-01-01

Udgivelsesdato: 2009 The precursory mire of the Middle Pennsylvanian (Bolsovian) Lower Radnice Coal was buried in situ by volcanic ash, preserving the taxonomic composition, spatial distribution, vertical strati¿cation, and synecology of this peat-forming ecosystem in extraordinary detail. Plant fossil remains represent the pre- eruption vegetation of the swamp, which resulted from accumulation of peat in a high-ash, planar (rheotrophic) mire situated in a narrow palaeovalley containing an...

Proceedings of the fourth annual conference on fossil energy materials

Energy Technology Data Exchange (ETDEWEB)

Judkins, R.R.; Braski, D.N. (comps.)

1990-08-01

The Fourth Annual Conference on Fossil Energy Materials was held in Oak Ridge, Tennessee, on may 15--17, 1990. The meeting was sponsored by the US Department of Energy's Office of Fossil Energy through the Advanced Research and Technology Development (AR TD) Materials Program, and ASM International. The objective of the AR TD Materials Program is to conduct research and development on materials for longer-term fossil energy applications as well as for generic needs of various fossil fuel technologies. The work is divided into the following categories: (1) Ceramics, (2) New Alloys, (3) Corrosion and Erosion, and (4) Technology Assessment and Technology Transfer. Individual projects are processed separately for the data bases.

A fossils detector

International Nuclear Information System (INIS)

Buffetaut, E.

1998-01-01

Because fossil bones are often rich in uraninite they can be detected using a portable gamma-ray detector run over the prospected site. Zones with higher radioactivity are possible accumulations of bones or skeletons. This method invented by R. Jones from the University of Utah (Salt Lake City, USA) has been successfully used in the field and led to the discovery of new dinosaur skeletons. Short paper. (J.S.)

Fossil nutlets of Boraginaceae from the continental Eocene of Hamada of Méridja (southwestern Algeria): The first fossil of the Borage family in Africa.

Science.gov (United States)

Hammouda, Sid Ahmed; Weigend, Maximilian; Mebrouk, Fateh; Chacón, Juliana; Bensalah, Mustapha; Ensikat, Hans-Jürgen; Adaci, Mohammed

2015-12-01

The Paleogene deposits of the Hamada of Méridja, southwestern Algeria, are currently dated as lower-to-middle Eocene in age based on fossil gastropods and charophytes. Here we report the presence of fruits that can be assigned to the Boraginaceae s.str., apparently representing the first fossil record for this family in Africa, shedding new light on the historical biogeography of this group. Microscopic studies of the fossil nutlets were carried out and compared to extant Boraginaceae nutlets, and to types reported in the literature for this family. The fossils are strikingly similar in general size and morphology, particularly in the finer details of the attachment scar and ornamentation, to nutlets of extant representatives of the Boraginaceae tribe Echiochileae, and especially the genus Ogastemma. We believe that these nutlets represent an extinct member of this lineage. The Ogastemma-like fossils indicate that the Echiochileae, which are most diverse in northern Africa and southwestern Asia, have a long history in this region, dating back to the Eocene. This tribe corresponds to the basal-most clade in Boraginaceae s.str., and the fossils described here agree well with an assumed African origin of the family and the Boraginales I, providing an important additional calibration point for dating the phylogenies of this clade. © 2015 Botanical Society of America.

The Development of the Silurian Trilobite Aulacopleura koninckii Reconstructed by Applying Inferred Growth and Segmentation Dynamics: A Case Study in Paleo-Evo-Devo

Directory of Open Access Journals (Sweden)

Nigel C. Hughes

2017-05-01

Full Text Available Fossilized growth series provide rare glimpses into the development of ancient organisms, illustrating descriptively how size and shape changed through ontogeny. Occasionally fossil preservation is such that it is feasible to test alternative possibilities about how ancient development was regulated. Here we apply inferred developmental parameters pertaining to size, shape, and segmentation in the abundant and well-preserved 429 Myr old trilobite Aulacopleura koninckii that we have investigated previously to reconstruct the post-embryonic ontogeny of this ancient arthropod. Our published morphometric analyses associated with model testing have shown that: specification of the adult number of trunk segments (polymorphic in this species was determined precociously in ontogeny; that growth regulation was targeted (i.e., compensatory, such that each developmental stage exhibited comparable variance in size and shape; and that growth gradients operating along the main body axis, both during juvenile and adult ontogeny, resulted from a form of growth control based on positional specification. While such developmental features are common among extant organisms, our results represent the oldest evidence for them within Metazoa. Herein, the novel reconstruction of the development of Aulacopleura koninckii permits visualization of patterns of relative and absolute growth and segmentation as never before possible for a fossilized arthropod ontogeny. By conducting morphometric analysis of appropriate data sets it is thus possible to move beyond descriptive ontogenetic studies and to address questions of high interest for evolutionary developmental biology using data from fossils, which can help elucidate both how developmental processes themselves evolve and how they affect the evolution of organismal body patterning. By extending similar analyses to other cases of exceptional preservation of fossilized ontogeny, we can anticipate beginning to realize the

Clustering fossils in solid inflation

Energy Technology Data Exchange (ETDEWEB)

Akhshik, Mohammad, E-mail: m.akhshik@ipm.ir [Department of Physics, Sharif University of Technology, Tehran (Iran, Islamic Republic of)

2015-05-01

In solid inflation the single field non-Gaussianity consistency condition is violated. As a result, the long tenor perturbation induces observable clustering fossils in the form of quadrupole anisotropy in large scale structure power spectrum. In this work we revisit the bispectrum analysis for the scalar-scalar-scalar and tensor-scalar-scalar bispectrum for the general parameter space of solid. We consider the parameter space of the model in which the level of non-Gaussianity generated is consistent with the Planck constraints. Specializing to this allowed range of model parameter we calculate the quadrupole anisotropy induced from the long tensor perturbations on the power spectrum of the scalar perturbations. We argue that the imprints of clustering fossil from primordial gravitational waves on large scale structures can be detected from the future galaxy surveys.

Emissions Scenarios and Fossil-fuel Peaking

Science.gov (United States)

Brecha, R.

2008-12-01

Intergovernmental Panel on Climate Change (IPCC) emissions scenarios are based on detailed energy system models in which demographics, technology and economics are used to generate projections of future world energy consumption, and therefore, of greenhouse gas emissions. Built into the assumptions for these scenarios are estimates for ultimately recoverable resources of various fossil fuels. There is a growing chorus of critics who believe that the true extent of recoverable fossil resources is much smaller than the amounts taken as a baseline for the IPCC scenarios. In a climate optimist camp are those who contend that "peak oil" will lead to a switch to renewable energy sources, while others point out that high prices for oil caused by supply limitations could very well lead to a transition to liquid fuels that actually increase total carbon emissions. We examine a third scenario in which high energy prices, which are correlated with increasing infrastructure, exploration and development costs, conspire to limit the potential for making a switch to coal or natural gas for liquid fuels. In addition, the same increasing costs limit the potential for expansion of tar sand and shale oil recovery. In our qualitative model of the energy system, backed by data from short- and medium-term trends, we have a useful way to gain a sense of potential carbon emission bounds. A bound for 21st century emissions is investigated based on two assumptions: first, that extractable fossil-fuel resources follow the trends assumed by "peak oil" adherents, and second, that little is done in the way of climate mitigation policies. If resources, and perhaps more importantly, extraction rates, of fossil fuels are limited compared to assumptions in the emissions scenarios, a situation can arise in which emissions are supply-driven. However, we show that even in this "peak fossil-fuel" limit, carbon emissions are high enough to surpass 550 ppm or 2°C climate protection guardrails. Some

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.

Development of concepts for a zero-fossil-energy greenhouse

NARCIS (Netherlands)

Ooster, A. van 't; Henten, E.J. van; Janssen, E.G.O.N.; Bot, G.P.A.; Dekker, E.

2008-01-01

Dutch government and greenhouse horticultural practice aim for strongly reduced fossil energy use and of environmental loads in 2010 and energy neutral greenhouses in 2020. This research aims to design a greenhouse concept with minimal use of fossil energy and independent of nearby greenhouses. The

Material flow analysis of fossil fuels in China during 2000-2010.

Science.gov (United States)

Wang, Sheng; Dai, Jing; Su, Meirong

2012-01-01

Since the relationship between the supply and demand of fossil fuels is on edge in the long run, the contradiction between the economic growth and limited resources will hinder the sustainable development of the Chinese society. This paper aims to analyze the input of fossil fuels in China during 2000-2010 via the material flow analysis (MFA) that takes hidden flows into account. With coal, oil, and natural gas quantified by MFA, three indexes, consumption and supply ratio (C/S ratio), resource consumption intensity (RCI), and fossil fuels productivity (FFP), are proposed to reflect the interactions between population, GDP, and fossil fuels. The results indicated that in the past 11 years, China's requirement for fossil fuels has been increasing continuously because of the growing mine productivity in domestic areas, which also leads to a single energy consumption structure as well as excessive dependence on the domestic exploitation. It is advisable to control the fossil fuels consumption by energy recycling and new energy facilities' popularization in order to lead a sustainable access to nonrenewable resources and decrease the soaring carbon emissions.

Preservation of a Late Glacial terrestrial and Holocene estuarine record on the margins of Kaipara Harbour, Northland, New Zealand

International Nuclear Information System (INIS)

Nichol, S.; Deng, Y.; Horrocks, M.; Zhou, W.; Hume, T.

2009-01-01

Subtidal to intertidal deposits from the margins of Kaipara Harbour in Northland preserve a c. 23,000 year incomplete sedimentary record of the transition from terrestrial to estuarine conditions. Cores are used to reconstruct the depositional setting for this transition, interpreted as a succession from dune and freshwater wetland to shallow estuarine environments. The fossil pollen record provides a proxy of Last Glacial Maximum and Late Glacial vegetation for the area. Stability of the Pleistocene dune landscape during the postglacial marine transgression is interpreted on the basis of strong dominance of tall forest taxa (Dacrydium) in the pollen record and soil development in dune sands, with preservation aided by location along the estuary margin. During the Holocene, reworking of the buried dune and wetland sediments has only reached to a depth of 1.5 m below the modern tidal flat. As such, the site provides a rare example of good preservation of Pleistocene deposits at the coast, where extensive reworking and loss of record are more typical. (author). 41 refs., 6 figs., 1 tab

Fossil fuel power generation within the European Research Area

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-12-10

The report is the first in a series of three produced by the PowerClean Thematic Network that looks at and defines future requirements for research and development of fossil fuel power generation in the European Union. It makes the case for fossil fuel R & D with emphasis on the need for clean coal technologies (to increased efficiency and other CO{sub 2} capture and storage) For satisfying future energy demands of the enlarged European Union between now and 2030. The report concludes that affirmative R, D and D action is needed to support the EU power industry, working together on a Europe-wide basis, to establish the use of coal and other fossil fuels in near-zero emissions power plant. The role model would be the European Research Area, as in the Sixth Framework Programme (FP6), but with a more comprehensive range of technical objectives recognising the importance of fossil fuels. Section headings are: introduction; current energy use; future needs and requirements; the future for clean fossil fuel energy in Europe; comparison with approaches adopted elsewhere (USA Vision 21 and FutureGen programmes, Japan); and responsibilities for EU coal R, D & D. 14 refs., 9 figs., 4 tabs.

An econometrics view of worldwide fossil fuel consumption and the role of US

International Nuclear Information System (INIS)

Shafiee, Shahriar; Topal, Erkan

2008-01-01

Crude oil, coal and gas, known as fossil fuels, play a crucial role in the global economy. This paper proposes new econometrics modelling to demonstrate the trend of fossil fuels consumption. The main variables affecting consumption trends are: world reserves, the price of fossil fuels, US production and US net imports. All variables have been analysed individually for more than half a century. The research found that while the consumption of fossil fuels worldwide has increased trends in the US production and net imports have been dependent on the type of fossil fuels. Most of the US coal and gas production has been for domestic use, which is why it does not have a strong influence on worldwide fossil fuel prices. Moreover, the reserves of fossil fuels have not shown any diminution during the last couple of decades and predictions that they were about to run out are not substantiated. The nominal and real price of fossil fuels was found to change depending on the type. Finally, estimates of three econometric models for the consumption of fossil fuels from 1949 to 2006 are presented which identify the effects of significant variables

Partially incorrect fossil data augment analyses of discrete trait evolution in living species.

Science.gov (United States)

Puttick, Mark N

2016-08-01

Ancestral state reconstruction of discrete character traits is often vital when attempting to understand the origins and homology of traits in living species. The addition of fossils has been shown to alter our understanding of trait evolution in extant taxa, but researchers may avoid using fossils alongside extant species if only few are known, or if the designation of the trait of interest is uncertain. Here, I investigate the impacts of fossils and incorrectly coded fossils in the ancestral state reconstruction of discrete morphological characters under a likelihood model. Under simulated phylogenies and data, likelihood-based models are generally accurate when estimating ancestral node values. Analyses with combined fossil and extant data always outperform analyses with extant species alone, even when around one quarter of the fossil information is incorrect. These results are especially pronounced when model assumptions are violated, such as when there is a trend away from the root value. Fossil data are of particular importance when attempting to estimate the root node character state. Attempts should be made to include fossils in analysis of discrete traits under likelihood, even if there is uncertainty in the fossil trait data. © 2016 The Authors.

Remarkable preservation of terpenoids and record of volatile signalling in plant-animal interactions from Miocene amber.

Science.gov (United States)

Dutta, Suryendu; Mehrotra, Rakesh C; Paul, Swagata; Tiwari, R P; Bhattacharya, Sharmila; Srivastava, Gaurav; Ralte, V Z; Zoramthara, C

2017-09-08

Plants produce and release a large array of volatile organic compounds that play many ecological functions. These volatile plant metabolites serve as pollinator attractants, herbivore and pathogen repellents and protect plants from abiotic stresses. To date, the geological evolution of these organic compounds remains unknown. The preservation potential of these metabolites in the fossil record is very poor due to their low boiling points. Here we report a series of volatile sesquiterpenoids, including δ-elemene, α-copaene, β-elemene, β-caryophyllene, α-humulene, germacrene D, δ-cadiene and spathunenol, from early Miocene (~17 million year) amber from eastern India. The survival of these unaltered bioterpenoids can be attributed to the existence of extraordinary taphonomic conditions conducive to the preservation of volatile biomolecules through deep time. Furthermore, the occurrence of these volatiles in the early Miocene amber suggests that the plants from this period had evolved metabolic pathways to synthesize these organic molecules to play an active role in forest ecology, especially in plant-animal interactions.

Partial preservation of the Tentaculites Crotalinus shell from Ponta Grossa Formation (Devonian)

International Nuclear Information System (INIS)

Ciguel, J.H.G.; Roesler, O.

1988-01-01

This paper deals with an analysis of a single specimen of Tentaculites crotalinus SALTER emend. CIGUEL et al. (1984) that present a possible partial preservation of the shell. It comes from an outcrop of the Grossa Formation (Devonian) near Jaguariaiva, State of Parana. The skeletal microstructure of the Tentaculitoidea shell rather poorly Known. Thus, the phylogenetic relationships of these invertebrates still uncertain. Tentaculitids are very common fossils in Devonian Ponta Grossa Formation (Parana Basin) but so far Known only from external and internal moulds. The objective of this study is to demonstrate wheter the layer found in between the internal and external mould is or not a case shell preservation. The chemical composition of this layer and of the external mould was analysed by X rays. X rays difratometry was applied only to the matrix (at the external mould). The structure of the supposed shell remain was studied by binocular stereomicroscope and scanning electron microscope. It revealed a foliate structure due to several paralel to subparalel oriented lamelae, with a chemical composition distinct from the matrix, and some elements possibly mantained from the original shell composition. Thus, a partial preservation of the original shell seems to be the better explanation for this case. This shell would be composed by calcium carbonate disposed in laminar layers, the outer ones being impregnated by Fe and Mn molecules during the diagenetic processes. The skeletal composition and microstructure would suggest a molluscan affinity for the tentaculitida Order. (auThor) [pt

Education Program on Fossil Resources Including Coal

Science.gov (United States)

Usami, Masahiro

Fossil fuels including coal play a key role as crucial energies in contributing to economic development in Asia. On the other hand, its limited quantity and the environmental problems causing from its usage have become a serious global issue and a countermeasure to solve such problems is very much demanded. Along with the pursuit of sustainable development, environmentally-friendly use of highly efficient fossil resources should be therefore, accompanied. Kyushu-university‧s sophisticated research through long years of accumulated experience on the fossil resources and environmental sectors together with the advanced large-scale commercial and empirical equipments will enable us to foster cooperative research and provide internship program for the future researchers. Then, this program is executed as a consignment business from the Ministry of Economy, Trade and Industry from 2007 fiscal year to 2009 fiscal year. The lecture that uses the textbooks developed by this program is scheduled to be started a course in fiscal year 2010.

CAUSAL RELATIONSHIP BETWEEN FOSSIL FUEL CONSUMPTION AND ECONOMIC GROWTH IN JAPAN: A MULTIVARIATE APPROACH

Directory of Open Access Journals (Sweden)

Hazuki Ishida

2013-01-01

Full Text Available This paper explores whether Japanese economy can continue to grow without extensive dependence on fossil fuels. The paper conducts time series analysis using a multivariate model of fossil fuels, non-fossil energy, labor, stock and GDP to investigate the relationship between fossil fuel consumption and economic growth in Japan. The results of cointegration tests indicate long-run relationships among the variables. Using a vector error-correction model, the study reveals bidirectional causality between fossil fuels and GDP. The results also show that there is no causal relationship between non-fossil energy and GDP. The results of cointegration analysis, Granger causality tests, and variance decomposition analysis imply that non-fossil energy may not necessarily be able to play the role of fossil fuels. Japan cannot seem to realize both continuous economic growth and the departure from dependence on fossil fuels. Hence, growth-oriented macroeconomic policies should be re-examined.

Preserving Canadian Exceptionalism: An Educator's Context

Science.gov (United States)

Shaker, Paul

2009-01-01

In this article, the author discusses the educational and societal differences between Canada and the United States. He claims that an egocentric culture, committed to immediate gratification, stands in the way of a healthy response to change. People are always seeking accommodation to the changes around them. When people choose familiar behaviour…

Hybrid Food Preservation Program Improves Food Preservation and Food Safety Knowledge

Science.gov (United States)

Francis, Sarah L.

2014-01-01

The growing trend in home food preservation raises concerns about whether the resulting food products will be safe to eat. The increased public demand for food preservation information led to the development of the comprehensive food preservation program, Preserve the Taste of Summer (PTTS). PTTS is a comprehensive hybrid food preservation program…

Microalgal and terrestrial transport biofuels to displace fossil fuels

NARCIS (Netherlands)

Reijnders, L.

2009-01-01

Terrestrial transport biofuels differ in their ability to replace fossil fuels. When both the conversion of solar energy into biomass and the life cycle inputs of fossil fuels are considered, ethanol from sugarcane and biodiesel from palm oil do relatively well, if compared with ethanol from corn,

Environmental damage caused by fossil fuels consumption

International Nuclear Information System (INIS)

Barbir, F.; Veziroglu, T.N.

1991-01-01

This paper reports that the objectives of this study is to identify the negative effects of the fossil fuels use and to evaluate their economic significance. An economic value of the damage for each of the analyzed effects has been estimated in US dollars per unit energy of the fuel used ($/GJ). This external costs of fossil fuel use should be added to their existing market price, and such real costs should be compared with the real costs of other, environmentally acceptable, energy alternatives, such as hydrogen

Divesting from Fossil Fuels Makes Sense Morally… and Financially

Science.gov (United States)

Cleveland, Cutler J.; Reibstein, Richard

2015-01-01

Should university endowments divest from fossil fuels? A public discussion of this question has seen some university presidents issuing statements that they would not divest--that investments should not be used for "political action." Many universities hold large endowments that have significant positions in fossil fuel companies or…

Clean fossil-fuelled power generation

International Nuclear Information System (INIS)

Oliver, Tony

2008-01-01

Using fossil fuels is likely to remain the dominant means of producing electricity in 2030 and even 2050, partly because power stations have long lives. There are two main ways of reducing CO 2 emissions from fossil-fuelled power plants. These are carbon capture and storage (CCS), which can produce near-zero CO 2 emissions, and increases in plant efficiency, which can give rise to significant reductions in CO 2 emissions and to reduced costs. If a typical UK coal-fired plant was replaced by today's best available technology, it would lead to reductions of around 25% in emissions of CO 2 per MW h of electricity produced. Future technologies are targeting even larger reductions in emissions, as well as providing a route, with CCS, to zero emissions. These two routes are linked and they are both essential activities on the pathway to zero emissions. This paper focuses on the second route and also covers an additional third route for reducing emissions, the use of biomass. It discusses the current status of the science and technologies for fossil-fuelled power generation and outlines likely future technologies, development targets and timescales. This is followed by a description of the scientific and technological developments that are needed to meet these challenges. Once built, a power plant can last for over 40 years, so the ability to upgrade and retrofit a plant during its lifetime is important

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)

Influence of fossil energy applications on environmental pollution

Energy Technology Data Exchange (ETDEWEB)

Balat, M.; Ayar, G.; Oguzhan, C.; Uluduz, H.; Faiz, U. [University of Mahallesi, Trabzon (Turkey)

2007-07-01

The aim of this work is to investigate influence of fossil energy applications on the environmental pollution. Turkey's high rate of economic growth experienced during much of the 1990s, besides resulting in booming industrial production, also led to higher levels of energy consumption, imports, air and water pollution, and greater risks to the country's environment. Air pollution is a major problem in Turkey, with key pollutants including sulfur dioxide, suspended particulates, nitrogen oxides, and carbon dioxide. In Turkey, carbon dioxide emissions from fossil fuels totaled about 50.07 million tons in 2001. However, fuel share of carbon emissions in 2001 was oil 44.2%, coal 38.8%, and natural gas 16.9%. Total carbon dioxide emissions from fossil fuels are expected to be 104 million tons in 2025.

Software preservation

Directory of Open Access Journals (Sweden)

Tadej Vodopivec

2011-01-01

Full Text Available Comtrade Ltd. covers a wide range of activities related to information and communication technologies; its deliverables include web applications, locally installed programs,system software, drivers, embedded software (used e.g. in medical devices, auto parts,communication switchboards. Also the extensive knowledge and practical experience about digital long-term preservation technologies have been acquired. This wide spectrum of activities puts us in the position to discuss the often overlooked aspect of the digital preservation - preservation of software programs. There are many resources dedicated to digital preservation of digital data, documents and multimedia records,but not so many about how to preserve the functionalities and features of computer programs. Exactly these functionalities - dynamic response to inputs - render the computer programs rich compared to documents or linear multimedia. The article opens the questions on the beginning of the way to the permanent digital preservation. The purpose is to find a way in the right direction, where all relevant aspects will be covered in proper balance. The following questions are asked: why at all to preserve computer programs permanently, who should do this and for whom, when we should think about permanent program preservation, what should be persevered (such as source code, screenshots, documentation, and social context of the program - e.g. media response to it ..., where and how? To illustrate the theoretic concepts given the idea of virtual national museum of electronic banking is also presented.

If an antelope is a document, then a rock is data: preserving earth science samples for the future

Science.gov (United States)

Ramdeen, S.

2015-12-01

As discussed in seminal works by Briet (1951) and Buckland (1998), physical objects can be considered documents when given specific context. In the case of an antelope, in the wild it's an animal, in a zoo it's a document. It is the primary source of information, specifically when it is made an object of study. When discussing earth science data, we may think about numbers in a spreadsheet or verbal descriptions of a rock. But what about physical materials such as cores, cuttings, fossils, and other tangible objects? The most recent version of the American Geophysical Union's data position statement states data preservation and management policies should apply to both "digital data and physical objects"[1]. If an antelope is a document, than isn't a rock a form of data? Like books in a library or items in a museum, these objects require surrogates (digital or analog) that allow researchers to access and retrieve them. Once these scientific objects are acquired, researchers can process the information they contain. Unlike books, and some museum materials, most earth science objects cannot yet be completely replaced by digital surrogates. A fossil may be scanned, but the original is needed for chemical testing and ultimately for 'not yet developed' processes of scientific analysis. These objects along with their metadata or other documentation become scientific data when they are used in research. Without documentation of key information (i.e. the location where it was collected) these objects may lose their scientific value. This creates a complex situation where we must preserve the object, its metadata, and the connection between them. These factors are important as we consider the future of earth science data, our definitions of what constitutes scientific data, as well as our data preservation and management practices. This talk will discuss current initiatives within the earth science communities (EarthCube's EC3 and iSamples; USGS's data preservation program

A CHARACEAN THALLUS WITH ATTACHED GYROGONITES AND ASSOCIATED FOSSIL CHAROPHYTES FROM THE MAASTRICHTIAN OF THE EASTERN PYRENEES (CATALONIA, SPAIN)(1).

Science.gov (United States)

Villalba-Breva, Sheila; Martín-Closas, Carles

2011-02-01

The new species Clavatoraxis microcharophorus is described from the Lower Maastrichtian of the Eastern Pyrenees (Catalonia, Spain). Microchara sp. gyrogonites were found in anatomical connection with this thallus, attached to bract-cell rosettes and coated by a structural tunica, formed by an expanded bract cell. This is a feature unknown in extant characeans, which only display lime incrustations similar to tunicae in extremely alkaline and well-illuminated environments. This is the first time that a complete fossil characean is described. The attribution of characean vegetative remains to the genus Clavatoraxis shows that this genus is not exclusive of clavatoraceans as previously thought. The taphonomic study of C. microcharophorus sp. nov. and associated fossil charophytes, along with sedimentological and microfacies analyses, has enabled us to characterize the habitat of this species in the Maastrichtian lake of Vallcebre. They grew forming meadows, and their remains were deposited in the poorly oxygenated lake bottom, where they were well preserved. A number of other characeans and porocharaceans were living in shallower belts. This was the case for Peckichara sp. and Munieria grambasti in the freshwater lacustrine meadows. Another species, Feistiella malladae, was found parautochthonous in brackish lakes. © 2011 Phycological Society of America.

A synthesis of carbon dioxide emissions from fossil-fuel combustion

DEFF Research Database (Denmark)

Andres, R.J.; Boden, T.A.; Bréon, F.-M.

2012-01-01

This synthesis discusses the emissions of carbon dioxide from fossil-fuel combustion and cement production. While much is known about these emissions, there is still much that is unknown about the details surrounding these emissions. This synthesis explores our knowledge of these emissions in terms......; and the uncertainties associated with these different aspects of the emissions. The magnitude of emissions from the combustion of fossil fuels has been almost continuously increasing with time since fossil fuels were first used by humans. Despite events in some nations specifically designed to reduce emissions......, or which have had emissions reduction as a byproduct of other events, global total emissions continue their general increase with time. Global total fossilfuel carbon dioxide emissions are known to within 10% uncertainty (95% confidence interval). Uncertainty on individual national total fossil-fuel carbon...

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

The late Middle Pleistocene hominin fossil record of eastern Asia: synthesis and review.

Science.gov (United States)

Bae, Christopher J

2010-01-01

Traditionally, Middle Pleistocene hominin fossils that cannot be allocated to Homo erectus sensu lato or modern H. sapiens have been assigned to different specific taxa. For example, in eastern Asia, these hominin fossils have been classified as archaic, early, or premodern H. sapiens. An increasing number of Middle Pleistocene hominin fossils are currently being assigned to H. heidelbergensis. This is particularly the case for the African and European Middle Pleistocene hominin fossil record. There have been suggestions that perhaps the eastern Asian late Middle Pleistocene hominins can also be allocated to the H. heidelbergensis hypodigm. In this article, I review the current state of the late Middle Pleistocene hominin fossil record from eastern Asia and examine the various arguments for assigning these hominins to the different specific taxa. The two primary conclusions drawn from this review are as follows: 1) little evidence currently exists in the eastern Asian Middle Pleistocene hominin fossil record to support their assignment to H. heidelbergensis; and 2) rather than add to the growing list of hominin fossil taxa by using taxonomic names like H. daliensis for northeast Asian fossils and H. mabaensis for Southeast Asian fossils, it is better to err on the side of caution and continue to use the term archaic H. sapiens to represent all of these hominin fossils. What should be evident from this review is the need for an increase in the quality and quantity of the eastern Asian hominin fossil data set. Fortunately, with the increasing number of large-scale multidisciplinary paleoanthropological field and laboratory research projects in eastern Asia, the record is quickly becoming better understood. Copyright © 2010 Wiley-Liss, Inc.

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.

Changes in Ocular Surface Characteristics after Switching from Benzalkonium Chloride-Preserved Latanoprost to Preservative-Free Tafluprost or Benzalkonium Chloride-Preserved Tafluprost

Directory of Open Access Journals (Sweden)

Naoto Tokuda

2017-01-01

Full Text Available Purpose. The aim of the present study was to examine the effects of switching from Latanoprost ophthalmic solution containing a preservative to preservative-free Tafluprost ophthalmic solution or Tafluprost containing a preservative on ocular surfaces. Materials and Methods. Forty patients (40 eyes with glaucoma (mean age: 62.0 ± 10.9 years using Latanoprost with preservative for six months or longer were assigned either to a Tafluprost-containing-preservative group (20 eyes or preservative-free-Tafluprost group (20 eyes. The intraocular pressure, corneal epithelial barrier function (fluorescein uptake concentration with fluorophotometer FL-500, superficial punctate keratopathy (AD classification, and tear film breakup time (TBUT were assessed before switching and at 12 weeks after switching. Results. No significant differences in intraocular pressure were noted after switching in either group. Corneal epithelial barrier function was improved significantly after switching in both the Tafluprost-containing-preservative and the preservative-free-Tafluprost groups. There were no significant differences in AD scores after switching in the Tafluprost-containing-preservative group, but significant improvements were noted in the preservative-free-Tafluprost group. No significant differences in TBUT were noted in the Tafluprost-containing-preservative or preservative-free-Tafluprost groups after switching. Conclusion. After switching from preservative Latanoprost to Tafluprost containing-preservative or preservative-free Tafluprost, corneal epithelial barrier function was improved while the intraocular pressure reduction was retained.

Changes in Ocular Surface Characteristics after Switching from Benzalkonium Chloride-Preserved Latanoprost to Preservative-Free Tafluprost or Benzalkonium Chloride-Preserved Tafluprost.

Science.gov (United States)

Tokuda, Naoto; Kitaoka, Yasushi; Matsuzawa, Akiko; Tsukamoto, Ayaka; Sase, Kana; Sakae, Shinsuke; Takagi, Hitoshi

2017-01-01

The aim of the present study was to examine the effects of switching from Latanoprost ophthalmic solution containing a preservative to preservative-free Tafluprost ophthalmic solution or Tafluprost containing a preservative on ocular surfaces. Forty patients (40 eyes) with glaucoma (mean age: 62.0 ± 10.9 years) using Latanoprost with preservative for six months or longer were assigned either to a Tafluprost-containing-preservative group (20 eyes) or preservative-free-Tafluprost group (20 eyes). The intraocular pressure, corneal epithelial barrier function (fluorescein uptake concentration with fluorophotometer FL-500), superficial punctate keratopathy (AD classification), and tear film breakup time (TBUT) were assessed before switching and at 12 weeks after switching. No significant differences in intraocular pressure were noted after switching in either group. Corneal epithelial barrier function was improved significantly after switching in both the Tafluprost-containing-preservative and the preservative-free-Tafluprost groups. There were no significant differences in AD scores after switching in the Tafluprost-containing-preservative group, but significant improvements were noted in the preservative-free-Tafluprost group. No significant differences in TBUT were noted in the Tafluprost-containing-preservative or preservative-free-Tafluprost groups after switching. After switching from preservative Latanoprost to Tafluprost containing-preservative or preservative-free Tafluprost, corneal epithelial barrier function was improved while the intraocular pressure reduction was retained.

A synthesis of carbon dioxide emissions from fossil-fuel combustion

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R. J. Andres

2012-05-01

Full Text Available This synthesis discusses the emissions of carbon dioxide from fossil-fuel combustion and cement production. While much is known about these emissions, there is still much that is unknown about the details surrounding these emissions. This synthesis explores our knowledge of these emissions in terms of why there is concern about them; how they are calculated; the major global efforts on inventorying them; their global, regional, and national totals at different spatial and temporal scales; how they are distributed on global grids (i.e., maps; how they are transported in models; and the uncertainties associated with these different aspects of the emissions. The magnitude of emissions from the combustion of fossil fuels has been almost continuously increasing with time since fossil fuels were first used by humans. Despite events in some nations specifically designed to reduce emissions, or which have had emissions reduction as a byproduct of other events, global total emissions continue their general increase with time. Global total fossil-fuel carbon dioxide emissions are known to within 10 % uncertainty (95 % confidence interval. Uncertainty on individual national total fossil-fuel carbon dioxide emissions range from a few percent to more than 50 %. This manuscript concludes that carbon dioxide emissions from fossil-fuel combustion continue to increase with time and that while much is known about the overall characteristics of these emissions, much is still to be learned about the detailed characteristics of these emissions.

Fossilized Mammalian Erythrocytes Associated With a Tick Reveal Ancient Piroplasms.

Science.gov (United States)

Poinar, George

2017-07-01

Ticks transmit a variety of pathogenic organisms to vertebrates, especially mammals. The fossil record of such associations is extremely rare. An engorged nymphal tick of the genus Ambylomma in Dominican amber was surrounded by erythrocytes from its mammalian host. Some of the exposed erythrocytes contained developmental stages of a hemoprotozoan resembling members of the Order Piroplasmida. The fossil piroplasm is described, its stages compared with those of extant piroplasms, and reasons provided why the mammalian host could have been a primate. The parasites were also found in the gut epithelial cells and body cavity of the fossil tick. Aside from providing the first fossil mammalian red blood cells and the first fossil intraerythrocytic hemoparasites, the present discovery shows that tick-piroplasm associations were already well established in the Tertiary. This discovery provides a timescale that can be used in future studies on the evolution of the Piroplasmida. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com Version of Record, first published online March 20, 2017 with fixed content and layout in compliance with Art. 8.1.3.2 ICZN.

Fossil energy savings potential of sugar cane bio-energy systems

DEFF Research Database (Denmark)

Nguyen, Thu Lan T; Hermansen, John Erik; Sagisaka, Masayuki

2009-01-01

One important rationale for bio-energy systems is their potential to save fossil energy. Converting a conventional sugar mill into a bio-energy process plant would contribute to fossil energy savings via the extraction of renewable electricity and ethanol substituting for fossil electricity...... and gasoline, respectively. This paper takes a closer look at the Thai sugar industry and examines two practical approaches that will enhance fossil energy savings. The first one addresses an efficient extraction of energy in the form of electricity from the excess bagasse and cane trash. The second while...... proposing to convert molasses or sugar cane to ethanol stresses the use of bagasse as well as distillery spent wash to replace coal in meeting ethanol plants' energy needs. The savings potential achieved with extracting ethanol from surplus sugar versus current practice in sugar industry in Thailand amounts...

The extent of the preserved feathers on the four-winged dinosaur Microraptor gui under ultraviolet light.

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David W E Hone

Full Text Available BACKGROUND: The holotype of the theropod non-avian dinosaur Microraptor gui from the Early Cretaceous of China shows extensive preservation of feathers in a halo around the body and with flight feathers associated with both the fore and hindlimbs. It has been questioned as to whether or not the feathers did extend into the halo to reach the body, or had disassociated and moved before preservation. This taxon has important implications for the origin of flight in birds and the possibility of a four-winged gliding phase. METHODOLOGY/PRINCIPAL FINDINGS: Examination of the specimen under ultraviolet light reveals that these feathers actually reach the body of the animal and were not disassociated from the bones. Instead they may have been chemically altered by the body tissues of the animal meaning that they did not carbonise close into the animal or more likely were covered by other decaying tissue, though evidence of their presence remains. CONCLUSIONS/SIGNIFICANCE: These UV images show that the feathers preserved on the slab are genuinely associated with the skeleton and that their arrangement and orientation is likely correct. The methods used here to reveal hidden features of the specimen may be applicable to other specimens from the fossil beds of Liaoning that produced Microraptor.

Refining of fossil resin flotation concentrate from western coal. Final report

Energy Technology Data Exchange (ETDEWEB)

Jensen, G.F.; Miller, J.D.

1995-02-16

During the past several years, significant research efforts have been made to develop process technology for the selective flotation of fossil resin from western coals. As a result of these efforts, several new flotation technologies have been developed. Operation of a proof-of-concept continuous flotation circuit showed the selective flotation process to be sufficiently profitable to justify the development of a fossil resin industry. However, little attention has been given to the refining of the fossil resin flotation concentrate although solvent refining is a critical step for the fossil resin to become a marketable product. In view of this situation, DOE funded this two-year project to evaluate the following aspects of the fossil resin refining technology: 1) Characterization of the fossil resin flotation concentrate and its refined products; 2) Kinetics of fossil resin extraction; 3) Effects of operating variables on solvent extraction; 4) Extraction solvents; 5) Proof-of-concept continuous refining tests; and 6) Technical and economic analysis. The results from this research effort have led to the following conclusions: Hexane- or heptane-refined fossil resin has a light-yellow color, a melting point of 140 - 142{degrees}C, a density of 1.034 gram/cm, and good solubility in nonpolar solvents. Among the four solvents evaluated (hexane, heptane, toluene and ethyl acetate), hexane is the most appropriate solvent based on overall technical and economic considerations. Batch extraction tests and kinetic studies suggest that the main interaction between the resin and the solvent is expected to be the forces associated with solvation phenomena. Temperature has the most significant effect on extraction rate. With hexane as the solvent, a recovery of 90% cam be achieved at 50{degrees}C and 10% solids concentration with moderate agitation for 1 hour.

The global environment effects of fossil and nuclear fuels

International Nuclear Information System (INIS)

Kemeny, L.G.

1981-01-01

The relative risks and environmental impacts of coal and uranium fueled power plants are dicussed. Fossil-fuel power plants are associated with a build-up of carbon dioxide levels and consequent climatic changes, release of sulphur dioxide and resultant acid rains and radioactive emissions. In comparing the discharges per megawatt year of sulphur dioxide, nitrogen dioxide and radioactive Ra-226 and Ra-225 in fly ash from coal and other fossil plants with Kr-85 and I-131 from nuclear plants, the fossil plants have a much poorer performance. Estimates indicate that nuclear energy can be adopted on a large scale as an alternative to coal without any increase in hazards and with a probability of a substantial reduction

Metamorphosis Is Ancestral for Crown Euarthropods, and Evolved in the Cambrian or Earlier.

Science.gov (United States)

Wolfe, Joanna M

2017-09-01

Macroevolutionary developmental biology employs fossilized ontogenetic data and phylogenetic comparative methods to probe the evolution of development at ancient nodes. Despite the prevalence of ecologically differentiated larval forms in marine invertebrates, it has been frequently presumed that the ancestors of arthropods were direct developers, and that metamorphosis may not have evolved until the Ordovician or later. Using fossils and new dated phylogenies, I infer that metamorphosis was likely ancestral for crown arthropods, contradicting this assumption. Based on a published morphological dataset encompassing 217 exceptionally preserved fossil and 96 extant taxa, fossils were directly incorporated into both the topology and age estimates, as in "tip dating" analyses. Using data from post-embryonic fossils representing 25 species throughout stem and crown arthropod lineages (as well as most of the 96 extant taxa), characters for metamorphosis were assigned based on inferred ecological changes in development (e.g., changes in habitat and adaptive landscape). Under all phylogenetic hypotheses, metamorphosis was supported as most likely ancestral to both ecdysozoans and euarthropods. Care must be taken to account for potential drastic post-embryonic morphological changes in evolutionary analyses. Many stem group euarthrpods may have had ecologically differentiated larval stages that did not preserve in the fossil record. Moreover, a complex life cycle and planktonic ecology may have evolved in the Ediacaran or earlier, and may have typified the pre-Cambrian explosion "wormworld" prior to the origin of crown group euarthropods. © The Author 2017. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

MFTF exception handling system

International Nuclear Information System (INIS)

Nowell, D.M.; Bridgeman, G.D.

1979-01-01

In the design of large experimental control systems, a major concern is ensuring that operators are quickly alerted to emergency or other exceptional conditions and that they are provided with sufficient information to respond adequately. This paper describes how the MFTF exception handling system satisfies these requirements. Conceptually exceptions are divided into one of two classes. Those which affect command status by producing an abort or suspend condition and those which fall into a softer notification category of report only or operator acknowledgement requirement. Additionally, an operator may choose to accept an exception condition as operational, or turn off monitoring for sensors determined to be malfunctioning. Control panels and displays used in operator response to exceptions are described

Ancient feeding ecology inferred from stable isotopic evidence from fossil horses in South America over the past 3 Ma

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Alberdi María T

2011-06-01

Full Text Available Abstract Background Stable isotope ratios (13C/12C and 18O/16O in fossil teeth and bone provide key archives for understanding the ecology of extinct horses during the Plio-Pleistocene in South America; however, what happened in areas of sympatry between Equus (Amerhippus and Hippidion is less understood. Results Here, we use stable carbon and oxygen isotopes preserved in 67 fossil tooth and bone samples for seven species of horses from 25 different localities to document the magnitude of the dietary shifts of horses and ancient floral change during the Plio-Pleistocene. Dietary reconstructions inferred from stable isotopes of both genera of horses present in South America document dietary separation and environmental changes in ancient ecosystems, including C3/C4 transitions. Stable isotope data demonstrate changes in C4 grass consumption, inter-species dietary partitioning and variation in isotopic niche breadth of mixed feeders with latitudinal gradient. Conclusions The data for Hippidion indicate a preference varying from C3 plants to mixed C3-C4 plants in their diet. Equus (Amerhippus shows three different patterns of dietary partitioning Equus (A. neogeus from the province of Buenos Aires indicate a preference for C3 plants in the diet. Equus (A. andium from Ecuador and Equus (A. insulatus from Bolivia show a preference for to a diet of mixed C3-C4 plants, while Equus (A. santaeelenae from La Carolina (sea level of Ecuador and Brazil are mostly C4 feeders. These results confirm that ancient feeding ecology cannot always be inferred from dental morphology. While the carbon isotope composition of horses skeletal material decreased as latitude increased, we found evidence of boundary between a mixed C3/C4 diet signal and a pure C4 signal around 32° S and a change from a mixed diet signal to an exclusively C3 signal around 35°S. We found that the horses living at high altitudes and at low to middle latitude still have a C4 component in their

Fossilization History of Fossil Resin from Jambi Province (Sumatra, Indonesia Based on Physico-Chemical Studies

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Beata Naglik

2018-03-01

Full Text Available A unique specimen of fossil resin originating from the Dipterocarpaceae tree family found in Miocene brown coal deposits in Jambi Province (Sumatra, Indonesia was investigated via microscopic observations, microhardness testing and infrared and Raman spectroscopic methods. Its form is rare in nature, being an aggregate of three varieties of resin differing in colour, transparency and internal structure. This suggests the formation of the resins at different stages. Further alteration processes, including fossilization and maturation of the resin in a swamp environment resulted in stepwise aromatization of the cyclohexane ring in steroids and cross-linking through formation of ester bonds as well as carbon–carbon bonds between steroid molecules. The various environmental and geological conditions affecting the formation processes of the resins were recorded in their physico-chemical properties. Additionally, heating conditions accelerated by volcanism were proposed as a factor determining the maturation grade of the resin.

Material Flow Analysis of Fossil Fuels in China during 2000–2010

Science.gov (United States)

Wang, Sheng; Dai, Jing; Su, Meirong

2012-01-01

Since the relationship between the supply and demand of fossil fuels is on edge in the long run, the contradiction between the economic growth and limited resources will hinder the sustainable development of the Chinese society. This paper aims to analyze the input of fossil fuels in China during 2000–2010 via the material flow analysis (MFA) that takes hidden flows into account. With coal, oil, and natural gas quantified by MFA, three indexes, consumption and supply ratio (C/S ratio), resource consumption intensity (RCI), and fossil fuels productivity (FFP), are proposed to reflect the interactions between population, GDP, and fossil fuels. The results indicated that in the past 11 years, China's requirement for fossil fuels has been increasing continuously because of the growing mine productivity in domestic areas, which also leads to a single energy consumption structure as well as excessive dependence on the domestic exploitation. It is advisable to control the fossil fuels consumption by energy recycling and new energy facilities' popularization in order to lead a sustainable access to nonrenewable resources and decrease the soaring carbon emissions. PMID:23365525

Hydrogen production econometric studies. [hydrogen and fossil fuels

Science.gov (United States)

Howell, J. R.; Bannerot, R. B.

1975-01-01

The current assessments of fossil fuel resources in the United States were examined, and predictions of the maximum and minimum lifetimes of recoverable resources according to these assessments are presented. In addition, current rates of production in quads/year for the fossil fuels were determined from the literature. Where possible, costs of energy, location of reserves, and remaining time before these reserves are exhausted are given. Limitations that appear to hinder complete development of each energy source are outlined.

A Paleocene penguin from New Zealand substantiates multiple origins of gigantism in fossil Sphenisciformes.

Science.gov (United States)

Mayr, Gerald; Scofield, R Paul; De Pietri, Vanesa L; Tennyson, Alan J D

2017-12-12

One of the notable features of penguin evolution is the occurrence of very large species in the early Cenozoic, whose body size greatly exceeded that of the largest extant penguins. Here we describe a new giant species from the late Paleocene of New Zealand that documents the very early evolution of large body size in penguins. Kumimanu biceae, n. gen. et sp. is larger than all other fossil penguins that have substantial skeletal portions preserved. Several plesiomorphic features place the new species outside a clade including all post-Paleocene giant penguins. It is phylogenetically separated from giant Eocene and Oligocene penguin species by various smaller taxa, which indicates multiple origins of giant size in penguin evolution. That a penguin rivaling the largest previously known species existed in the Paleocene suggests that gigantism in penguins arose shortly after these birds became flightless divers. Our study therefore strengthens previous suggestions that the absence of very large penguins today is likely due to the Oligo-Miocene radiation of marine mammals.

Fossil Microorganisms in Archaean

Science.gov (United States)

Astafleva, Marina; Hoover, Richard; Rozanov, Alexei; Vrevskiy, A.

2006-01-01

Ancient Archean and Proterozoic rocks are the model objects for investigation of rocks comprising astromaterials. The first of Archean fossil microorganisms from Baltic shield have been reported at the last SPIE Conference in 2005. Since this confeence biomorphic structures have been revealed in Archean rocks of Karelia. It was determined that there are 3 types of such bion structures: 1. structures found in situ, in other words microorganisms even-aged with rock matrix, that is real Archean fossils biomorphic structures, that is to say forms inhabited early formed rocks, and 3. younger than Archean-Protherozoic minerali microorganisms, that is later contamination. We made attempt to differentiate these 3 types of findings and tried to understand of burial of microorganisms. The structures belongs (from our point of view) to the first type, or real Archean, forms were under examination. Practical investigation of ancient microorganisms from Green-Stone-Belt of Northern Karelia turns to be very perspective. It shows that even in such ancient time as Archean ancient diverse world existed. Moreover probably such relatively highly organized cyanobacteria and perhaps eukaryotic formes existed in Archean world.

The exceptional generalised geometry of supersymmetric AdS flux backgrounds

Energy Technology Data Exchange (ETDEWEB)

Ashmore, Anthony [Merton College, University of Oxford,Merton Street, Oxford, OX1 4JD (United Kingdom); Mathematical Institute, University of Oxford, Andrew Wiles Building,Woodstock Road, Oxford, OX2 6GG (United Kingdom); Petrini, Michela [Sorbonne Université, UPMC Paris 06, UMR 7589,LPTHE, 75005 Paris (France); Waldram, Daniel [Department of Physics, Imperial College London,Prince Consort Road, London, SW7 2AZ (United Kingdom)

2016-12-29

We analyse generic AdS flux backgrounds preserving eight supercharges in D=4 and D=5 dimensions using exceptional generalised geometry. We show that they are described by a pair of globally defined, generalised structures, identical to those that appear for flat flux backgrounds but with different integrability conditions. We give a number of explicit examples of such “exceptional Sasaki-Einstein” backgrounds in type IIB supergravity and M-theory. In particular, we give the complete analysis of the generic AdS{sub 5} M-theory backgrounds. We also briefly discuss the structure of the moduli space of solutions. In all cases, one structure defines a “generalised Reeb vector” that generates a Killing symmetry of the background corresponding to the R-symmetry of the dual field theory, and in addition encodes the generic contact structures that appear in the D=4 M-theory and D=5 type IIB cases. Finally, we investigate the relation between generalised structures and quantities in the dual field theory, showing that the central charge and R-charge of BPS wrapped-brane states are both encoded by the generalised Reeb vector, as well as discussing how volume minimisation (the dual of a- and F-maximisation) is encoded.

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

Implicit CO_2 prices of fossil fuel use in Switzerland

International Nuclear Information System (INIS)

Schleiniger, Reto