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Van, Dijk D. E. "Contributions to knowledge of some Southern African fossil sites and their fossils /." Link to the online version, 2000. http://hdl.handle.net/10019/3561.
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Van, Dijk D. E. "Contributions to knowledge of some Southern African fossil sites and their fossils." Thesis, Stellenbosch : University of Stellenbosch, 2001. http://hdl.handle.net/10019.1/2988.
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Thesis (MSc (Botany and Zoology. Palaeontology))--University of Stellenbosch, 2001.The fossil sites and fossils reported here range from the Archaean to the Recent. Information is presented on the circumstances of the discovery of some fossil sites in Southern Africa. A number of fossil sites, some of which can no longer be studied, are photographically recorded. Some recorded sites were relocated, while failure to locate others is noted. The assemblages at selected fossil sites are compiled, including some additions to their floras and faunas. Certain individual fossils are illustrated and discussed. Techniques which are not standard are outlined.
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Rydin, Catarina. "The Gnetales : fossils and phylogenies /." Stockholm : Department of Botany, Stockholm University, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-488.
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Brocks, Jochen J. "Molecular fossils in Archean rocks." Phd thesis, School of Geosciences, 2001. http://hdl.handle.net/2123/14300.
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Mounce, Ross. "Comparative cladistics : fossils, morphological data partitions and lost branches in the fossil tree of life." Thesis, University of Bath, 2013. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.642021.
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In this thesis I attempt to gather together a wide range of cladistic analysis of fossil and extant taxa representing a diverse array of phylogenetic groups. I use this data to quantitatively compare the effect of fossil taxa relative to extant taxa in terms of support for relationships, number of most parsimonious trees (MPTs) and leaf stability. In line with previous studies I find that the effects of fossil taxa are seldom different to extant taxa – although I highlight some interesting exceptions. I also use this data to compare the phylogenetic signal within vertebrate morphological data sets, by choosing to compare cranial data to postcranial data. Comparisons between molecular data and morphological data have been previously well explored, as have signals between different molecular loci. But comparative signal within morphological data sets is much less commonly characterized and certainly not across a wide array of clades. With this analysis I show that there are many studies in which the evidence provided by cranial data appears to be be significantly incongruent with the postcranial data – more than one would expect to see just by the effect of chance and noise alone. I devise and implement a modification to a rarely used measure of homoplasy that will hopefully encourage its wider usage. Previously it had some undesirable bias associated with the distribution of missing data in a dataset, but my modification controls for this. I also take an in-depth and extensive review of the ILD test, noting it is often misused or reported poorly, even in recent studies. Finally, in attempting to collect data and metadata on a large scale, I uncovered inefficiencies in the research publication system that obstruct re-use of data and scientific progress. I highlight the importance of replication and reproducibility – even simple re-analysis of high profile papers can turn up some very different results. Data is highly valuable and thus it must be retained and made available for further re-use to maximize the overall return on research investment.
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Herman, Julie D. "Fossil preservation and the effects of groundwater leaching on fossils in the Yorktown Formation (Upper Pliocene), Virginia." Thesis, Virginia Polytechnic Institute and State University, 1987. http://hdl.handle.net/10919/90972.
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Patterns of fossil diagenesis caused by groundwater leaching provide insight into how shells are altered. This study analyzes fossils in unconsolidated terrigenous sediments from the Virginia Coastal Plain, unlike previous studies conducted mostly in carbonate terranes. The vertical and lateral distribution of diagenetic states was mapped in an outcrop (63 m by 2.1 m) of the Yorktown Formation. A paleostream channel located at one end was incised during the Pleistocene and filled with sediments of the Shirley Formation. The Tabb Formation unconformably overlies the outcrop. Acidic groundwater caused the observed patterns of fossil and sediment diagenesis. These patterns include zones of fossil alteration, diagenetic stratification of the sediment, and fossil diagenesis on a microstructural level.
Groundwater movement, controlled by the presence of the paleochannel, caused diagenetic alteration or complete dissolution of the fossils, and possibly caused precipitation of fine-grained iron oxyhydroxides. All carbonate material in the vicinity of the paleochannel is completely dissolved away, although iron oxyhydroxide coatings of fossils remain. Away from the paleochannel Crepidula fornicata (gastropod; aragonite), Ostrea sp. (bivalve; calcite), Balanus sp. (barnacle; calcite), and bryozoans (calcite) are found in parallel zones of alteration that dip toward the paleochannel and cut across horizontal sedimentologic and fossiliferous layers.
Groundwater also leached the Yorktown sediments. This alteration caused a diagenetic stratification of the sediment, with unaltered greenish-gray silty fine sand along the base of the outcrop, overlain by leached yellowish-brown silty fine sand and areas of concentrated iron oxyhydroxides.
The preservation of both aragonitic and calcitic shells was affected by groundwater movement. Original aragonitic shell material is found as chalky, uncrystallized specimens or neomorphosed shells, or is completely dissolved with only molds or ghosts remaining. Neomorphosed specimens typically consist of calcite-replaced shell material with pockets of original aragonite, and sparry calcite filling empty shell cavities. Original calcitic shell material is either chalky or unaltered. Chalky shells range from relatively hard to soft and pasty. Crepidula shells of intermediate chalkiness tend to separate into thin flakes, caused by dissolution along growth surfaces. Chalkiness of pasty shells is caused by dissolution of shell material (without recrystallization) and not simply loss of organic matrix. SEM photos of Crepidula reveal the more porous and leached appearance of chalky shells in contrast with hard; unaltered shells. The presence of chalky aragonitic and calcitic shells indicates that chalky textures are, to some degree, independent of mineralogy and microstructure.M.S.
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Buckman, James O. "Lower Carboniferous trace fossils from northwest Ireland." Thesis, Queen's University Belfast, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262648.
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Legg, David. "The impact of fossils on arthropod phylogeny." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/24168.
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The arthropods are the most diverse, abundant and ubiquitous phylum on Earth. Five main extant groups (subphyla) can be recognized: Pycnogonida, Euchelicerata, Myriapoda, Hexapoda, and Crustacea. Each group displays a distinctive body plan and a suite of autapomorphies that makes determining their interrelationships difficult. Although a variety of hypotheses have been proposed regarding their interrelationships, just three have frequently been recovered in recent phylogenetic analyses. Rather than representing incongruent topologies these hypotheses represent variations of the position of the root on the same parent topology. The long histories of the major arthropod subclades, which had begun to diverge by, at least, the early Cambrian, means that long-branch artefacts are highly probable. To alleviate potential long-branch attraction and provide a more accurate placement of the root, 214 fossil taxa were coded into an extensive phylogenetic data set of 753 discrete characters, which also includes 95 extant panarthropods and two cycloneuralian outgroups. Preference was given to those fossil taxa thought to occur during the cladogenesis of the major arthropod clades, i.e. the lower and middle Cambrian. An extensive study of material from the middle Cambrian Burgess Shale Formation and the coeval Stephen Formation in British Columbia (Canada) was undertaken. This study focussed primarily on taxa thought to represent 'upper stem-group euarthropods', namely bivalved arthropods and megacheirans ('great-appendage' arthropods), as they will have the greatest utility in polarizing relationships within the arthropod crown-group [= Euarthropoda]. This study includes the description of three new genera and four new species: the bivalved arthropods Nereocaris exilis, N. briggsi, and Loricicaris spinocaudatus; and the megacheiran Kootenichela deppi; and a restudy selected material referred to the bivalved arthropod taxa Isoxys, Canadaspis perfecta, Odaraia alata and Perspicaris dictynna. Results of the phylogenetic analysis and additional perturbation tests confirm the utility of these taxa for polarizing relationships within Euarthropoda and reducing long-branch artefacts. For example, the hexapods were recovered within a paraphyletic Crustacea, a result anticipated by molecular phylogenetic analyses but until now elusive in morphological phylogenies. Perturbation tests indicate that close affinities of myriapods and hexapods, a result common in morphological analyses, is the result of a long-branch artefact caused by the convergent adaptation to a terrestrial habit, which is broken by the addition of fossil material. The phylogeny provides a detailed picture of character acquisition in the arthropod stem group.
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Cooper, Robert D. "A knowledge-based system for hominid fossils." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0004420.
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Friend, Duncan. "Palaeobiology of Palaeozoic medusiform stem group echinoderms." Thesis, University of Cambridge, 1995. https://www.repository.cam.ac.uk/handle/1810/265414.
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The morphological details of both external and internal anatomy of a group of Palaeozoic fossil medusiform animals are described with the aid of text-figures and plates with explanatory drawings. This fossil group had a worldwide distribution with a stratigraphic range from the Lower Cambrian to the Upper Devonian and includes the following taxa:- Eldonia ludwigi Walcott 1911, E. eumorphus sp. nov., Rotadiscus grandis Sun and Hou 1987, Discophylluni peltatum Hall 1847, D. mirabile Chapman 1926, D. cryptophya (Clarke) 1900. Newly recognised anatomical structures for E. ludwigi include c.30, internal, radially-arranged, bifurcating lobes, a coelomic sac surrounding the alimentary canal, internal structures assumed to represent gonads and c.4 oral tentacles. E. eumorphus has c.44 internal bifurcating lobes associated with rows of pores on the ventral surface, which form a possible respiratory system. R. granclis has a possibly mineralised dorsal surface, rows of pores on the ventral surface and a tentacular appendage with arm-like extensions. Discophylluni 1s characterised by an ornamented dorsal surface with rows of elaborate pores. The nomenclature 1s revised, anatomical reconstructions are presented and modes of life in terms of feeding and benthic versus pelagic existence are discussed. It is concluded that this group, the Discophylla (equivalent in status to a new class), lies within the stem group Echinodermata. As a consequence, current understanding of the early evolution of the Echinodermata, especially with respect to internal anatomy, is questioned . A number of medusiforrn fossils, not studied in detail as part of this work, are discussed and tentatively assigned to the Discophylla.
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Durman, Peter Neville. "The origin and early evolution of graptolites and related hemichordates." Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.260643.
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Baky, Alaaeldin Mohamed Abdel. "Maastrichtian to early Eocene calcareous nannofossils from Egypt." Thesis, University College London (University of London), 1988. http://discovery.ucl.ac.uk/1317747/.
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A study of calcareous nannofossils from the Maastrichtian-Early Eocene from Egypt has resulted in the recognition of four Maastrichtian and seven Early Tertiary biostratigraphic zones. These nannoplankton zones are based upon local ranges and compared with the zones proposed by Martini (1971), Sissingh (1977), Verbeek (1977) and Romein (1979). A new zone, the Fasciculithus ragaae Zone is described and the E1lipsolithus macellus Zone and the Fasciculithus tympaniformis Zone are emended. Study of the vertical ranges of the species provided many markers (including the zonal markers) with distinctive first and/or last occurrence levels. The uppermost Maastrichtian and Lower Danian are missing in the study sections. There is no change in the lithology at the Cretaceous-Tertiary boundary as observed in the Esh Mellaha area, but biostratigraphic evidence shows that there is a time gap and the boundary missing. This boundary is, however, marked by a conglomerate band at Gebel Urn El Ghanayem, a thin bed of black non-calcareous shale at Gebel Duwi and a change in the lithology from chalky limestone (upper part of Sudr Chalk Formation) of Maastrichtian age to shale (lower part of Esna Shale Formation) of Early Palaeocene age at Wadi Tarfa. No continuous Cretaceous-Tertiary boundary sequence was analysed. The palaeoenvironment during the Maastrichtian-Early Eocene according to the nannofossil assemblages, was a warm open marine inner to outer shelf, although the absence of late Maastrichtian and early Danian age sediments limits observation and comment. One hundred and sixty five species have been identified. Descriptions, remarks and figures as well as schematic drawings of many species are presented. A new family RHOMBOASTERACEAE, a new genus Diadochiastozygus, five new species Fasciculithus ragaae, F. gelelii, Discoaster atefii, D. duwiensis and D. amrii are described. New combinations for Bomolithus megastypus, B. cantabriae, Diadochiastozygus imbriei, D. saepes, D. eosaepes, Tranolithus tarboulensis, Vekshinella dorfii and V. compacta are proposed. The evolution of some Cretaceous and Early Tertiary nannofloral groups is discussed and a link between the Bomolithus and Discoaster groups proposed.
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Yates, Timothy John Sturgis. "The selection of non-marine molluscan shells for radiocarbon dating." Thesis, University College London (University of London), 1986. http://discovery.ucl.ac.uk/1317885/.
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The use of shells from terrestrial and freshwater molluscs for radiocarbon dating has in the past been viewed with scepticism or even dismissed entirely because the results are prone to distortion from post-depositional diagenesis, or the incorporation of material with a low 14C/12C ratio whilst the mollusc was alive, or both. The thesis attempts to discuss how the relative importance of the two factors can be assessed and the corresponding ages corrected accordingly. Diagenesis was studied by comparing the structure and chemical composition of 39 species of British molluscs from modern specimens with those of fossil samples. Three main effects of diagenesis were studied using light and scanning electron microscopy, mass spectrometry and atomic absorption spectroscopy: the transformation of aragonite to calcite, a reduction in the standard deviation associated with the distribution of major ion concentrations within a shell population, and an enrichment in the lighter isotopes of carbon and oxygen. Only the transformation of mineralogy proved to be sufficiently sensitive to detect diagenetic material present at levels of 1-27%. The effects of diet and ambient carbon dioxide were studied by chemical analysis and mass spectrometry. Differences in stable isotope ratio values between micro-environments were found to be significantly greater than those between and within species. The established relationship between 13C, 14C and the environment can be used to identify shells in which the apparent age effect will be at a minimum. Comparison of 14C dates for charcoal and untreated shell samples showed that the above sources of error led to discrepancies of as much as 1500 years in the shell dates. Seven samples selected and pretreated in accordance with the procedures proposed in this thesis gave ages within two standard deviations of the values accepted for the deposit in question, and four samples gave ages which were being statistically identical with the accepted values. In addition, the screening tests permitted samples destined to give erroneous ages to be identified from the outset.
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Walkling, Adrian Paul. "Coleopteran records from the last interglacial-glacial transition." Thesis, Royal Holloway, University of London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302622.
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Metcalf, Sara J. "The palaeoenvironment and palaeoecology of a Middle Jurassic vertebrate-bearing fen-type paleosol in a coastal carbonate regime." Thesis, University of Bristol, 1995. http://hdl.handle.net/1983/955beb87-8c25-4857-ac91-c3451390ff62.
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Krentz, Hartmut. "The forelimb anatomy of Theropithecus brumpti and Theropithecus oswaldi from the Shungura Formation, Ethiopia /." Thesis, Connect to this title online; UW restricted, 1993. http://hdl.handle.net/1773/6533.
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Sookias, Roland. "Sustainable Fossils: Past Life for the Present and Future." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-160439.
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Fossils are a non-renewable natural resource and impart many different kinds of value including scientific, educational, aesthetic and via practical uses such as construction. They provide an entirely irreplaceable record of life on Earth yet ensuring their sustainable use has often been overlooked. Ten case examples of fossil sites, with a European focus but from around the world, are documented in a framework of economic, social and environmental spheres typically used in sustainable development theory. The sustainability of the way fossils are treated at the sites is examined, compared and discussed. Non-extractive uses are generally found to be most straightforwardly sustainable, but concerns such as pollution must be born in mind. Extractive uses (commercial collecting, quarrying) present more challenges but can be made sustainable by involvement of science and investment of profits. Without a coordinated global policy for sustainable development in all areas fossil use cannot be sustainable globally.
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Jackson, Illiam. "Morphometric analysis of Cambrian fossils and its evolutionary significance." Doctoral thesis, Uppsala universitet, Paleobiologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-319487.
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The Extended Evolutionary Synthesis (EES) is currently emerging as a theoretical alternative to the Modern Synthesis (MS) in which to frame evolutionary observations and interpretations. These alternative frameworks differ fundamentally in their understanding of the relative roles of the genotype, phenotype, development and environment in evolutionary processes and patterns. While the MS represents a gene-centred view of evolution, the EES instead emphasizes the interactions between organism, development and environment. This novel theoretical framework has generated a number of evolutionary predictions that are mutually incompatible with the equivalent of the MS. While research and empirical testing has begun on a number of these in a neontological context, the field of palaeontology has yet to contribute meaningfully to this endeavour. One of the reasons for this is a lack of methodological approaches capable of investigating relevant evolutionary patterns in the fossil record. In this thesis morphometric methods capable of providing relevant data are developed and employed in the analysis of Cambrian fossils. Results of these analyses provide empirical support for the process of evolution through phenotypic plasticity and genetic assimilation hypothesized by the EES. Furthermore, theoretical revision to the species concept in a palaeontological context is suggested. Finally, predictions of the EES specific to the fossil record are made explicit and promising directions of future research are outlined.
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Ketchum, Winn Addison. "Using Geographical Information Systems to Investigate Spatial Patterns in Fossils of Tapirus polkenis from the Gray Fossil Site, Washington County, Tennessee." Digital Commons @ East Tennessee State University, 2011. https://dc.etsu.edu/etd/1227.
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Discovered in 2000, the Gray Fossil Site provides a snapshot of the flora and fauna that lived during late Miocene to early Pliocene time in eastern Tennessee. These fossils occur in sediments consisting of fine-grained clays and sands of lacustrine origin, which were deposited after multiple sinkholes formed in the underlying Knox Group basement carbonates. Three-dimensional nearest neighbor analysis has been applied to fossils of Tapirus polkensis, characterizing the spatial patterns exhibited. These analyses determined the importance of taphonomic and depositional processes that occurred during the sites formation. Six characteristics were analyzed, four at the bone level including carnivore utilization, weathering, abrasion, and arthritis, and two at the specimen level, articulation and age class. Weathering, arthritis, and articulation, show clustered patterns indicating that the site had active predators, it consisted of many microenvironments, and deposition occurred in a passive setting. Although the current state of excavation makes any spatial analyses and taphonomic interpretations difficult, spatial analysis in both dimensions can be accomplished.
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Thomson, A. J. "Lower Cambrian trace fossils of the Amadeus Basin, central Australia /." Title page, abstract and contents only, 1992. http://web4.library.adelaide.edu.au/theses/09SB/09sbt482.pdf.
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Broce, Jesse S. "Taphonomic Characteristics of Fossils on the Burgess-shale-type Spectrum." Thesis, University of Missouri - Columbia, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=13877133.
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Korneisel, Dana Elaine. "Are 'exceptionally' preserved skeletal fossils necessarily exceptional chemically and cytologically?" Thesis, Virginia Tech, 2019. http://hdl.handle.net/10919/93932.
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At the macroscopic scale, vertebrate fossils are considered exceptional when non-biomineralized (soft) tissues are preserved. Histologically, high quality is defined by trueness to original shape of a bone, preservation of fine details (e.g. canaliculi), and presence or absence of matrix material in void spaces. Some fossils are hypothesized to preserve cells and durable organelles. Traditionally, cytological details and biomolecular remains have been sought in exceptional fossils. Durable cytological features such as melanosomes do appear to follow feather preservation, but traditionally exceptional fossils are not necessarily exceptional on a microscopic scale. Here, we analyze a feathered dinosaur specimen from the Jehol Lagerstätte to assess claims of blood cell preservation and the state of potential biomolecular preservation. Beipiaosaurus inexpectus is a fairly complete specimen with preserved feathers. Though crushed, fine details in thin section are prevalent. Using Raman spectroscopy, Energy Dispersive X-ray Spectrometry, and Time-of-Flight Secondary Ion Mass Spectroscopy we found no evidence of exceptional molecular preservation. Instead, we found evidence that the vasculature, once hypothesized to contain preserved red blood cells, is filled with clay minerals, with the purported cells chemically indistinguishable from materials of other shapes infilling the vessels. Despite yielding exceptional fossils, the preservational environment of the Jehol biota does not necessarily preserve exceptional details cytologically or biomolecularly. Consequently, we conclude that a systematic approach to biomolecular and cytological preservation studies should rely on traits other than classic exceptional preservation.Master of Science
What makes a fossil particularly excellent? Traditionally, fossils from animals with skeletons were considered high quality when many or most of the bones from an animal are preserved. If these bones line up with one another like they would in the animal when it was alive (i.e. are articulated) the fossil is even better. To be exceptional, though, soft tissues, or parts of the animal that were not hardened with minerals while the animal lived (e.g. feathers, skin) need to be preserved. All of these traits can be observed with the naked eye. With the use of a microscope, we can see how much a skeleton has been crushed and whether the spaces in the bone for blood vessels and cells have been well preserved. Additionally, we may be able to observe preserved cells, which would be exceptional. On an even smaller scale, the molecules present in a bone might be well or poorly preserved. How much the minerals that make up the bone have changed chemically from when the animal was alive is one indicator of quality. Another might be preservation of molecules that come from the animal such as DNA and the proteins present in bone. In this study, we chose an exceptional fossil based on the traits visible to the naked eye (many of the bones are present and it has feathers) and looked for evidence of cell and unique molecule preservation. On the microscope, we saw beautiful details of the structures in the bone that held bone cells and blood vessels. We also observed red spheres which have been described by other researchers as possible blood cells in the spaces for blood vessels. Using three types of machine which can identify minerals, elements, and molecules in the bone and vessels, we did not find any evidence that the spheres represent preserved blood cells. Nor did we find any evidence of exceptional molecules. However, we did find evidence that the bone itself is not highly changed from when the animal lived, though we see elements and molecules in the vessels that probably did not come from the animal. We started this study knowing that the fossil we chose is exceptional in some ways, but what we found shows that it has a mix of excellent and poor traits visible on the microscope and it does not have any excellent traits in terms of its molecules besides the minerals in the bone itself. We conclude that fossils that are exceptional in the traditional sense are not necessarily exceptional in other ways.
What makes a fossil particularly excellent? Traditionally, fossils from animals with skeletons were considered high quality when many or most of the bones from an animal are preserved. If these bones line up with one another like they would in the animal when it was alive (i.e. are articulated) the fossil is even better. To be exceptional, though, soft tissues, or parts of the animal that were not hardened with minerals while the animal lived (e.g. feathers, skin) need to be preserved. All of these traits can be observed with the naked eye. With the use of a microscope, we can see how much a skeleton has been crushed and whether the spaces in the bone for blood vessels and cells have been well preserved. Additionally, we may be able to observe preserved cells, which would be exceptional. On an even smaller scale, the molecules present in a bone might be well or poorly preserved. How much the minerals that make up the bone have changed chemically from when the animal was alive is one indicator of quality. Another might be preservation of molecules that come from the animal such as DNA and the proteins present in bone. In this study, we chose an exceptional fossil based on the traits visible to the naked eye (many of the bones are present and it has feathers) and looked for evidence of cell and unique molecule preservation. On the microscope, we saw beautiful details of the structures in the bone that held bone cells and blood vessels. We also observed red spheres which have been described by other researchers as possible blood cells in the spaces for blood vessels. Using three types of machine which can identify minerals, elements, and molecules in the bone and vessels, we did not find any evidence that the spheres represent preserved blood cells. Nor did we find any evidence of exceptional molecules. However, we did find evidence that the bone itself is not highly changed from when the animal lived, though we see elements and molecules in the vessels that probably did not come from the animal. We started this study knowing that the fossil we chose is exceptional in some ways, but what we found shows that it has a mix of excellent and poor traits visible on the microscope and it does not have any excellent traits in terms of its molecules besides the minerals in the bone itself. We conclude that fossils that are exceptional in the traditional sense are not necessarily exceptional in other ways.
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Tibbs, Sarah Louise. "Mineralization of fossils from the Lower Devonian Hunsruck Slate, Germany." Thesis, University of Bristol, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.393084.
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Ellis, Caroline Sarah. "Molluscan biostratigraphy of Flandrian slope deposits in East Sussex." Thesis, Imperial College London, 1985. http://hdl.handle.net/10044/1/7855.
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Van, Niel Brigitta E. "Early Cretaceous Nannoconus (Calcareous nannofossil, Incertae sedis) in NW Europe." Thesis, University College London (University of London), 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307692.
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Windley, Dawn Elizabeth. "Calcareous nannofossil applications in the study of cyclic sediments of the Cenomanian." Thesis, University College London (University of London), 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306898.
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Young, Melinda. "The foraminiferal and sedimentological dynamics of a Portuguese submarine canyon system." Thesis, University of Southampton, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.295866.
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Sutcliffe, Owen Edward. "The sedimentology and ichnofauna of the Lower Devonian Hunsrück Slate, Germany : taphonomy and palaeobiological significance." Thesis, University of Bristol, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246291.
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Porro, Francesca. "Understanding palynomorph distribution in turbidite systems." Thesis, University of Aberdeen, 2018. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=238813.
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Duncan, Ian. "The taphonomy of insects." Thesis, University of Bristol, 1997. http://hdl.handle.net/1983/b9255bb1-f863-469c-9511-7909e79353af.
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Willis, Addison O. "Trace and body fossils from the Cuyahoga Formation (Mississippian), Reynoldsburg, Ohio /." Connect to resource, 1996. http://hdl.handle.net/1811/31684.
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Savage, Derek Allan. "Terminal proterozoic stromatolite reefs with shelly fossils, Salient Platform, British Columbia." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=81434.
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The late Neoproterozoic Salient Platform (Byng Formation, upper Miette Group), located 50 km northwest of Jasper, Alberta, contains one of three known occurrences worldwide of the Cloudina-Namacalathus fossil assemblage.The Salient Platform initiated in relatively deep water (minimum 30-50 m) on Mount Machray. Lowermost carbonates on Salient Mountain and The Colonel were deposited in quiet environments behind the developing stromatolitic reef. The upper two thirds of the platform formed in shallow water and consists of huge, elongated Platella and Cryptozoon bioherms, within which most shelly fossils are found. Carbonate production is terminated by Gog Group siliciclastic sedimentation. Thin, shell-bearing stromatolitic carbonates discovered within the lowermost Gog Group bring into question the current position of the Precambrian-Cambrian boundary in the southern Rocky Mountains (western Canada).
Petrographic and geochemical data indicate that the Salient Platform has undergone significant diagenetic alteration. delta13C values of microsparitic limestones appear to retain a primary isotopic signature, which correlates well with coeval late Neoproterozoic successions worldwide.
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Boulton, Huw. "Taphonomy of non-biomineralised tissues in fossils from lacustrine Konservat-Lagerstätten." Thesis, University of Bristol, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.398539.
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Ando, Tatsuro, and n/a. "New Zealand fossil penguins : origin, pattern, and process." University of Otago. Department of Geology, 2007. http://adt.otago.ac.nz./public/adt-NZDU20080204.140701.
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Penguins are middle- to large-sized sea birds and are widely distributed in the Southern Hemisphere. They have completely lost the capability for the aerial flight, but are highly efficient wing-propelled swimmers and divers. They have a long fossil record over 60 million years, and their origin could possibly extend back to the late Cretaceous. This study aims to elaborate the course of penguin evolution and driving force of changes based on fossil records of penguins. Numerous fossil penguin specimens have been collected and studied from New Zealand, Antarctica, South America, Australia, and Africa. Studies on fossil penguins have spanned about 150 years history since Huxley (1859).
Previous works on fossil penguins have achieved excellent results, but at the same time, left considerable confusion on taxonomy and anatomical interpretation, mainly because of the poor nature of the penguin fossils in early studies. Examination of newly found materials and updated evaluation of previously studied materials are needed, using modern methods.
During about 150 years of fossil penguins study since Huxley1859, more than 40 genera and 70 species have been described. The number of specimens listed in the published literature amounts to more than 1300. Chapter II reviews all those fossil penguins in a summarised and consistent style, aiming to present the taxonomy used in this study as a primary and essential resource for research. The chapter also provides other information on fossil penguins, such as geological data and an assessment of the skeletal association of the specimens referred to a species.
Chapter III introduces the osteology of penguins, by describing and comparing the skeletal characteristics and variation of both extant and fossil species. Though previous works on penguins osteology are extensive, the interpretation of the homology, and resulted terminology, are occasionally inappropriate, or incorrect, because of the highly-specialised structure. Many of the new, yet undescribed, fossils prompt a comprehensive update of those previous studies, to understand the nature of morphological variation in penguins, and to correct or clarify confusion in previous works.
The New Zealand fossil penguin fauna is one of the most significant for fossil penguin studies, but there are many undescribed fossil penguin specimens. Chapter IV provides accounts of such materials. Chapter IV also reviews previously-described New Zealand fossil penguins, usually re-evaluated using new materials. This chapter includes reassessment of the controversial, first-described fossil penguin Palaeeudyptes antarcticus, description of an enigmatic new species (Pakudyptes hakataramea gen. et sp. nov.) which could elucidate the evolutionary pattern of the penguin wing, description of new materials of Platydyptes revealing a unique structure and functional interpretation, and redescriptions with functional interpretation of Pachydyptes and Archaeospheniscus.
Published relationships within penguins have not been adequately discussed but stated within rather rough frameworks, so that the relationships within penguins were unclear. Chapter V provides an explicit framework for the phylogeny of penguins. Osteology-based cladistic analysis was performed to seek out the relationships within penguins, using observations on both extant and fossil penguins. There are several important grades in penguin history, which are structurally distant from each other. Results also agree with the published views in which the extant penguins form a rigid group, but Simpson�s subfamily groupings are only partly supported. A postulated phylogenetic tree includes all known fossil penguin taxa including un-named ones.
Chapter VI, as a synthesis of contents of previous chapters, provides a broad interpretation of penguin evolution through the Cenozoic: origin, body size increase, demise of 'giant penguins', and the emergence of modern penguins. The chapter gives a global picture of the interaction of penguins, pinnipeds, cetaceans, and temperature and sea-level change. Two main sections are: 'Origin of penguins' and 'Evolutionary process of penguins.' The loss of aerial flight and increase of body size were possibly triggered by the K/T mass extinction event which drastically reduced the predatory pressure for early penguins. The 'giant penguins' survived until the Late Oligocene but declined as the oceans modernised, and new forms of whales with advanced feeding function appeared. There is controversy about appearance of modern penguins. The fossil-based hypothesis (relatively recent origin for crown-penguins) contradicts the molecular-based one (ancient origin for crown penguins), though 'hard evidence' at present does not easily refute either hypothesis.
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Bingham, Patrick Sean. "Stratigraphic and paleoenvironmental context of the Ingersoll shale, an upper cretaceous conservation Lagerstätte, Eutaw Formation, Eastern Alabama." Auburn, Ala., 2007. http://repo.lib.auburn.edu/2007%20Spring%20Theses/BINGHAM_PATRICK_34.pdf.
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McCoy, Michelle. "Effect of the trans-Arctic invasion on Pliocene predator-prey interactions on Tjörnes Peninsula, Iceland /." Electronic version (Microsoft Word), 2007. http://dl.uncw.edu/etd/2007-3/mccoym/michellemccoy.doc.
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Ross, Andrew J. "The Purbeck and Wealden cockroaches and their potential use in biostratigraphy." Thesis, University of Brighton, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341285.
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Davis, Paul G. "The taphonomy of birds." Thesis, University of Bristol, 1994. http://hdl.handle.net/1983/66bf971f-5ef0-44ec-83e5-92c7887f7471.
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Palaeo-ornithology has been dominated by taxonomy. To try and redress the balance and help palaeoecologists interpret fossil birds in a biological and ecological perspective, the taphonomy of birds needs to be fully understood. The taphonomy of birds is concerned with all processes from death to the collection of the fossil bird. Between these two points (the transfer of the organism from the biosphere to the lithosphere) a variety of forces and processes affect the bird/fossil. By means of experiments in the natural environment and in controlled conditions in the laboratory, and subsequent comparisons of the results with case studies of fossil assemblages, the processes leading to preservation can be deduced and the former living community restored on the basis of the fossil evidence. The research involved two main approaches: 1. experimental taphonomy / observational taphonomy; and 2. case histories of fossil communities and their interpretation. Experimental work was carried out in the natural environment. Two field sites were chosen in southern Florida, a freshwater environment and a marine environment. The monitoring and controlling of these experiments required knowledge and techniques in zoology, botany, ecology, sedimentology, limnology, marine biology, microbiology, pathology and forensic science. Results obtained included the effects of scavenging, anoxia, transport, rate of burial, and temperature on rates of decay, the causes of bird mortality, the processes resulting in disarticulation, and the effects of decay upon feathers. Once the experimentaVobservational data had been collected they allowed a series of taphonomic thresholds (a decay sequence) to be defined. These data were then applied to case studies of fossil bird assemblages from different sedimentological environments. The following LagersHitten were investigated: Messel (Eocene, Germany) = restricted lacustrine; Green River (Eocene, USA) = lacustrine; Solnhofen Lithographic Limestone (Jurassic, Germany) = restricted marine; La Meseta Formation (Eocene, Antarctica) = marine; Rancho La Brea (Pleistocene, USA) = terrestrial "trap". The biases in each environment were assessed (e.g. birds in an aquatic ten-estrial environment had a higher preservation potential than birds from a tenestrial environment). The fossil record of birds is not as depauperate as previously thought but is heavily biased, depending on the proximity of the bird's habitat to that of the preserving sedimentary environment. Marine and littoral birds are poorly represented even though they inhabit sedimentary environments with a high preservation potential. This reflects low densities of birds per unit area. Aquatic birds (and terrestrial birds that inhabit the ecotone surrounding freshwater together with some larger fOlIDS from further away) are much better represented. This is because they inhabit the only terrestrial environments with a high preservation potential, coupled with the high densities of individuals per unit area. The bias towards large terrestrial birds is due to their large bones being more resistant to transport induced damage. These results have implications for the understanding of the evolution of birds. Patterns of evolution in birds can not be fully resolved on fossil evidence alone; biases in the taphonomy of birds only permit a small proportion of species from certain environments to be preserved. The taphonomy of feathers was investigated and it was discovered that the "organic trace" that commonly represents the outline of the feather trace is the diagenetically altered glycocalyx of the bacteria that were degrading the feather. In several localities these feather-degrading bactelia are preserved in authigenic minerals. The taphonomy of bats and pterosaurs was also investigated. The similarity of anatomical structures of birds, bats and pterosaurs results in similar taphonomic pathways.
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Townsend, Marisia Jean. "The palaeogeography of the Lower Cretaceous Aysen Basin of southern Chile." Thesis, University of Bristol, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246282.
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Leeming, Peter Joseph. "'What do we collect and seek to interpret?' : fossils in Neolithic and Bronze Age contexts in Britain and Ireland." Thesis, University of Exeter, 2016. http://hdl.handle.net/10871/28005.
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A PhD thesis which draws together the evidence for the occurrence of fossil objects in archaeological sites in Great Britain and Ireland during the Neolithic, Chalcolithic and Bronze Age. The wider contexts of fossils discovered in sites of the same period in Europe and of fossils discovered in earlier periods (Palaeolithic and Mesolithic) are also discussed. This is also a re-examination and update of the work of Kenneth Oakley and as such investigates the folklore of fossils. The use of fossiliferous stone for lithics is also considered.
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Riley, David Anthony. "Preservation and taphonomy of the fossils of the Herefordshire (Silurian) Konservat-Lagerstätte." Thesis, University of Leicester, 2012. http://hdl.handle.net/2381/10317.
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The Herefordshire Lagerstätte represents a fully marine Silurian ecosystem, three dimensionally soft-bodied fossils, preserved by sparry calcite, which are recovered from carbonate concretions. Although, a taphonomic model exists it does not determine the pathways that led to their preservation, nor has it been tested on the other taxa recovered from the Lagerstätte. X-ray fluorescence (XRF) analysis indicates the sediment originated from an andesitic volcano from a destructive plate margin. Field relationships suggest that the bed was deposited from either a turbidity current or debris flow. Given the highly reactive nature of the volcanic ash, the cation exchanges that occur provide a mechanism for supersaturating the pore-fluid with carbonates. Examination of the four common taxa; Offacolus kingi (arthropod), Tanazios dokeron (arthropod), Kenostrychus clementsi (polychaete worm) and Acaenoplax hayae (mollusc), indicates a similar pathway of preservation. Energy-dispersive X-ray spectroscopy (EDX) identifies the only impurity within the fossil calcite is manganese; in comparison the concretion carbonates contain a variety of different cations. Therefore, the fossils and the concretions are the result of different processes, which were not coeval. Comparing the preservation Kenostrychus clementsi (polychaete) against experimental work indicates that preservation occurred within 6 days and rules out the occurrence of a void stage as previously thought. In addition, it also suggests that preservation was either instantaneous or there must have been an intermediate “medusa” stage that preserved the tissue prior to templating. Electron microprobe analysis (EMPA) data indicate that the clay minerals that precipitated around the decaying animal were templating the organic matter. To precipitate the sparry calcite without the void stage, an hypothesis is proposed in which the sparry calcite nucleates and grows through the soft tissues. Isotopic data indicates that the concretions are not produced by organic matter decay. This is supported by the lack of correlation between the concretion and the fossil and the occurrence of barren concretions. Radial variation in the mineralogy, chemistry and isotopic ratios support the hypothesis that these concretions grew concentrically around a non-organic nucleus. These exceptional conditions may account for a preservation style that is so far unique to this single exposure.
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Page, Alexander Alfred. "Graptolitic mudrocks and their implications for the taphonomy of organic compression fossils." Thesis, University of Leicester, 2008. http://hdl.handle.net/2381/30464.
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This thesis addresses graptolitic mudrocks in an Earth system context and examines issues concerning the preservation of organic carbon. It investigates the palaeoenvironmental and paleoecological aspects of these mudrocks. It relates their deposition to climate modulation in an hitherto-unrecognised Early Palaeozoic Icehouse, and reassesses the fossils of the problematic genus Dawsonia Nicholson. This work identifies seven glacial maxima in the Late Ordovician and Early Silurian recognised by the occurrence of well-dated glacial deposits coincident with stable isotope excursions and eustatic regressions. Comparison of these data with the occurrence of graptolitic shales reveals that deglacial transgressions led to increased stratification of the water column and the onset of widespread marine anoxia. The burial of organic carbon in these deglacial anoxic events may have served as a negative feedback mechanism by drawing down sufficient atmospheric carbon dioxide to prevent runaway warming and stabilise this long-lived Early Palaeozoic Icehouse. This study suggests that graptolites are best viewed as a mixed-layer zooplankton and that their occurrence in anoxic mudrocks should be regarded as representing the conditions they were preserved in rather than those in which they lived. Comparison of published data on graptolite diversity with the oxic-anoxic stratigraphy for the EPI shows there is no strong link between graptolite diversity and marine anoxia. Meanwhile, the general absence of graptolites from bioturbated facies may reflect enhanced decay and scavenging related to well-oxygenated conditions; whilst the documentation of rare occurrences of graptolites in oxic facies and those from above the storm wave base shows that they could live in well-oxygenated waters. Though anoxia alone is insufficient to explain the fossilisation of organic-walled fossils and conversion of subfossil cuticle to a more stable biopolymer may have inhibited degradation, it is clear that fossilisation does not render such fossils entirely inert or homogeneous. Analysis of multifaunal assemblages, such as those preserving Dawsonia Nicholson (shown to be brachiopods, crustacean tailpieces and an organic-walled problematicum), where graptolites co-occur with shelly fossils and diagenetic pyrite, shows that graptolites acted as a key site for phyllosilicate authigenesis in very low-grade metamorphism. Petrographic evidence and comparison with white mica crystallinity data suggests that the expulsion of volatiles in maturation may have catalysed the formation of phyllosilicates on these fossils. This mode of phyllosilicate formation may also account for the formation of phyllosilicate films on Burgess Shale fossils.
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Skinner, Ethan S. "Taphonomy of exceptionally preserved fossils from the Kinzers Formation (Cambrian), southeastern Pennsylvania." The Ohio State University, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=osu1090592371.
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Brooks, Bjorn-Gustaf James. "Computational geological approaches for assessing the diversity and ecological distribution of fossils." [Ames, Iowa : Iowa State University], 2009.
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Skinner, Ethan S. "Taphonomy of exceptionally perserved fossils from the Kinzers Formation (Cambrian), southeastern Pennsylvania." Connect to this title online, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1090592371.
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Thesis (Ph. D.)--Ohio State University, 2004.Title from first page of PDF file. Document formatted into pages; contains xiv, 167 p.; also includes graphics. Includes bibliographical references (p. 127-143).
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Wang, Xing. "Diversification précoce des cnidaires : études des microfossiles à préservation exceptionnelle de la Formation de Kuanchuanpu (base du Cambrien; env. 535 Ma), province de Shaanxi, Chine." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSE1308/document.
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Le Cambrien basal (Étage Fortunien, env. 535 Ma) de la Formation de Kuanchuanpu dans la Province chinoise du Shaanxi, contient une grande variété de Small Shelly Fossils (SSF) préservés grâce à une phosphatisation secondaire. On y trouve les éléments exosquelettiques de groups animaux très variés mais également des embryons et stades larvaires conservés en trois dimensions et interprétés par les auteurs précédents comme de possible cnidaires. Cette faune dans son ensemble est une source d’informations exceptionnelle sur les toutes premières étapes de la diversification animal avant qu’elle n’atteigne son plein développement (ex : au cours du Cambrien inférieur, Série 2, Étage 3). Nous avons exploré ici la morphologie de ces organismes fossiles submillimétriques au moyen de la Microscopie Électronique à Balayage (SEM) et de techniques microtomographiques aux rayons X (Computed X-ray Microtomography, XTM et Synchrotron X-ray Microtomography, SRXTM), testé les hypothèses concernant leurs possibles affinités avec les cnidaires et analysé leur possible relations phylogénétiques avec les groups actuels de cnidaires. Parmi ces fossiles, certains (ex : Olivooides et formes apparentées) peuvent être raisonnablement considérées comme des cnidaires sur la base de leur anatomie interne, leur symétrie radiale et leurs caractères externes, et pourraient appartenir au groupes-souche des Scyphozoa, Cubozoa et Anthozoa. Des représentants des groupescouronne Scyphozoa, Cubozoa, Anthozoa et Hydrozoa semblent apparaître plus tard dans l’évolution des cnidaires (pas avant le Cambrien inférieur Série 2, Étage 3) comme l’indiquent les méduses du gisement exceptionnel (Lagerstätte) de Chengjiang (env. 521 Ma) qui ressemblent en tout point aux méduses actuelles et possédaient déjà un système sensorial sophistiqué. Notre étude met en lumière une série de caractères atypiques chez les cnidaires ancestraux de Kuanchuanpu: 1) la coexistence de divers modes de symétrie, 2) la prédominance de la symétrie pentaradiale, 3) l’existence d’un mode de développement direct (apparemment sans larve planula) contrastant ainsi avec tous les cnidaires actuels et 4) une taille corporelle très petite compatible avec un mode de vie meiobenthiqueThe lowermost Cambrian (Fortunian Stage; ca. 535 Ma) Kuanchuanpu Formation from China contains a great variety of secondarily phosphatized Small Shelly Fossils such as exoskeletal elements of various animal groups but also yields three-dimension allypreserved embryos and larval stages interpreted as cnidarians by previous authors. This biota is an exceptional source of information on the early steps of animal biodiversification before its full development (e.g. early Cambrian, Series 2, Stage 3).We explored the morphology of these sub-millimetric fossil organisms by means of Scanning Electron Microscopy (SEM), Computed X-ray Microtomography (XTM) and Synchrotron X-ray Microtomography (SRXTM), and tested their cnidarian affinities and analyzed their possible relation to modern cnidarian groups. Some of them (e.g.Olivooides and related forms) can be reasonably considered as cnidarians based on their internal anatomy, radial symmetry and external features, and may belong to the stem groups Scyphozoa, Cubozoa and Anthozoa. Crown-group scyphozoans,cubozoans, anthozoans and hydrozoans seem to appear later in the evolution of cnidarians, not before Stage 3, Series 2 of the early Cambrian as indicated by the jellyfish from the Chengjiang Lagerstätte (ca. 521 Ma) which closely resemble modern tetraradial medusae and possessed sophisticated sensory organs. Our study highlights some important “atypical” features of the ancestral cnidarians from the Kuanchuanpubiota such as 1) the co-existence of diverse symmetry patterns, 2) the prevalence of pentaradial symmetry, 3) a possible direct development (with no planula larva) contrasting with all modern cnidarians and 4) a small body size consistent with ameiobenthic lifestyle
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Almond, J. E. "Studies on Palaeozoic Arthropoda." Thesis, University of Cambridge, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.384278.
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Budd, Graham Edward. "Cambrian arthropods from North Greenland and their evolutionary significance." Thesis, University of Cambridge, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.319381.
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Thompson, Jennifer Louise. "The significance of early hominid cranial variability." Thesis, Durham University, 1991. http://etheses.dur.ac.uk/5875/.
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The aims of this thesis are: 1. To examine patterns of morphological variation in the crania of extant species {Pan, Gorilla, Pongo, and H. sapiens) to determine if any common pattern of primate sexual dimorphism exists which could be used in the assessment of fossil hominid sexual dimorphism; 2. To examine patterns of between species variability among the crania of the above extant species to determine if characters exist which could be useful as taxonomic indicators, especially of specific distinctiveness in fossil Hominidae; and 3. To assess the validity of using traits which are dimorphic and/ or variable within species as taxonomic indicators in systematic analyses. This thesis entails an analysis of inter- and intra-specific diversity among the early hominids based on models derived from samples of modern H. sapiens and pongids. Metrical cranial characters were surveyed in order to assess the implications of their variability within the available early hominid sample {A. afarensis, A. africanus, A. robustus, A. boisei, H. habilis, and H. erectus) using univariate, multi variate, and cladistic analytical techniques. The univariate analysis found no common pattern of primate sexual dimorphism but it did identify characters of low sexual dimorphism and low variability common to all the extant hominoids. These were used to test the homogeneity of the fossil groups and indicated the possible heterogeneity of H. erectus, H. habilis, A. afarensis, and A. boisei. The remaining characters revealed an apparent trend among the hominids (fossil and modern) of dimorphic regions of the skull including the areas of nuchal and temporal muscle attachment, kyphosis of the basicrania, width of the palate, mandible, and base, and facial prognathism. The multivariate analyses used the patterns of variability and dimorphism known from the modern comparators to assess sex, degrees of sexual dimorphism, and homo geneity of the fossil samples. These analyses revealed the possible heterogeneity of H. erectus and A. afarensis, the sex of some individual specimens, and some interesting contrasts in the patterns of sexual dimorphism between the fossil and modern species. They also isolated KNM-ER 1805 as having unique basicranial proportions. Two different types of characters were used in cladistic analyses to determine which type produced the most parsimonious trees and the implications of their use for future cladistic analyses. The results show that non-variable, non-dimorphic traits generally produce more parsimonious trees than variable, dimorphic ones, thus demonstrating the importance of assessing within- and between-group variability of characters prior to cladistic analyses. The method of coding the data prior to the cladistic analysis was tested for its objectivity. The analyses showed that the constant used to code the data into discrete character states had a substantial effect upon the resultant trees. This study has demonstrated that characters have different properties due to the amount they vary or are dimorphic within groups and that utilising these characters for different purposes has the potential to enhance future systematic/ phyletic studies.
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Perry, Christopher Thomas. "Controls on reef framework and sediment preservation : examples from the Holocene and Pleistocene of Jamaica, and the Miocene of Mallorca." Thesis, University of Reading, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362054.
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