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Hanson, Dale Alan. "The fossil mammals of the southern basin of the John Day Formation, Oregon /." view abstract or download file of text, 2000. http://wwwlib.umi.com/cr/uoregon/fullcit?p1400405.
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Thesis (M.S.)--University of Oregon, 2000.Typescript. Includes vita and abstract. Includes bibliographical references (leaves 192-199). Also available for download via the World Wide Web; free to UO users.
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Meijaard, Erik. "Solving mammalian riddles : a reconstruction of the Tertiary and Quaternary distribution of mammals and their palaeoenvironments in island South-East Asia /." View thesis entry in Australian Digital Theses Program, 2004. http://thesis.anu.edu.au/public/adt-ANU20050924.221423/index.html.
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Schreve, Danielle Caroline. "Mammalian biostratigraphy of the later Middle Pleistocene in Britain." Thesis, University College London (University of London), 1998. http://discovery.ucl.ac.uk/1317926/.
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This study explores and develops the potential of fossil mammals to differentiate between the various climatic episodes of the post-Anglian Middle Pleistocene in Britain. Mammalian fossils are particularly valuable as biostratigraphic indicators on account of their morphological evolution and rapid turnover, through origination and extinction of species. Furthermore, the large-scale climatic fluctuations that affected north-west Europe during the Quaternary produced major shifts in the geographical distributions of many species, resulting in discernible patterns of presence and absence in the fossil record of a particular region. The development of a globally-applicable climatostratigraphic framework, based on the oxygen isotope record from deep-ocean sediments, has provided a new and challenging scheme for the interpretation of the British Quaternary record. Long fluvial sequences in Britain have been related to this record with considerable success, thereby providing a detailed archive of climatic change through the Pleistocene. The Thames valley was selected as a framework for the relative dating of the various climatic fluctuations, since it has been claimed to have the most reliably-dated long terrestrial sequence in the later Middle Pleistocene. The Thames model was therefore adopted as a testable hypothesis against which the mammalian evidence could be compared. The findings of this study confirm the presence of four complete climatic cycles between the Anglian and the Holocene, each with its own distinctive mammalian suite. In addition, it has been possible to identify subdivisions within these temperate stages, probably representing smaller-scale climatic fluctuations within an interglacial, and perhaps corresponding to isotopic substages. It has been possible to resolve a longstanding controversy concerning the age of the British type Hoxnian Interglacial. Amino acid geochronology had suggested that sediments at Hoxne belonged to a later interglacial than deposits from the first post-Anglian temperate episode in the Thames valley, such as Swanscombe. The results of the present study reveal close similarity between the mammalian fauna from Hoxne and that from Swanscombe, suggesting that there was indeed a single Hoxnian Interglacial, and that it directly post-dated the Anglian (i.e. Stage 11). Sediments of this age can be distinguished from those attributable to two other late Middle Pleistocene interglacials, all of them distinct from and older than, the Ipswichian. It has been suggested that distinctive mammalian assemblages can be identified from interglacials equivalent to oxygen isotope stages 9 and 7; moreover, it is apparent that the assemblages from warm Substages 7c and 7a differed from one another in species composition. Certain useful characters have also been determined, which can permit useful separation of some of the late Middle Pleistocene cold episodes, although in comparison with the interglacials, the evidence from these is scanty. The present study has provided a new biostratigraphic framework that may be both tested and refined as new sites become available in Britain, and also compared with the evidence from continental north-west Europe.
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Bassarova, Mina School of Biological Earth & Environmental Sciences UNSW. "Taphonomic and palaeoecological investigations of Riversleigh Oligo-miocene fossil sites: mammalian palaeocommunities and their habitats." Awarded by:University of New South Wales. School of Biological, Earth and Environmental Sciences, 2005. http://handle.unsw.edu.au/1959.4/23074.
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The palaeoecology of selected fossil sites from the Riversleigh World Heritage Area, northwestern Queensland, Australia, was studied with the aim of describing the palaeohabitats of the sites through the use of characteristics of mammalian community structure. Taphonomic analyses were carried out to determine whether the study sites represent allochthonous or autochthonous assemblages. Subsequently, ecological attributes of the mammalian fossil assemblages were inferred from functional morphology. Trophic and locomotor behaviours were used to describe the adaptive structure of communities and a method was established for inferring the locomotor behaviour of fossil taxa from morphometrics of their calcanea. Such ecological attributes of the assemblages can be used in reconstructing habitats. This is possible because modern mammalian community structure (as represented by ecological diversity/attribute characteristics) has been found to correlate with habitat structure and thus has predictive value, directly applicable in palaeoecology. Modern mammalian faunas from a variety of habitats around the world were used as possible analogues for the Riversleigh fossil faunas. Multivariate statistical techniques were explored for identifying potential similarities between the community structure of the fossil faunas and that of the modern faunas. Annual rainfall was then estimated for the fossil sites through regression analysis allowing climatic inference from the faunal palaeocommunities. On the basis of similarities in community structure, general habitat or vegetation structure was proposed for the fossil assemblages. The results of the analyses undertaken indicate that Riversleigh early-middle Miocene habitats were densely forested. The late Oligocene Quantum Leap Site local fauna and the late Miocene Encore Site local fauna suggest mixed vegetation, or more open environments. The trend of decreasing annual rainfall through the Miocene and the palaeohabitats of the Miocene sites proposed here fit the general pattern of vegetation and climate change during this period for the Australian continent as a whole.
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McLaughlin, Win, and Win McLaughlin. "Hawk Rim: A Geologic and Paleontological Description of a New Barstovian Locality in Central Oregon." Thesis, University of Oregon, 2012. http://hdl.handle.net/1794/12553.
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Hawk Rim represents a new mid-Miocene site in Eastern Oregon. This time period offers a rare chance to observe dramatic climatic changes, such as sudden warming trends. The site is sedimentologically and stratigraphically consistent with the Mascall Formation of the John Day Basin to the north and east of Hawk Rim. Hawk Rim preserves taxa such as canids Cynarctoides acridens and Paratomarctus temerarius, the felid Pseudaelurus skinneri, castorids Anchitheriomys and Monosaulax, tortoises and the remains of both cormorants and owls. Hawk Rim has yielded a new genus and species of mustelid. As individuals these taxa are of interest, but the real story is told by the paleoecology. The lower reaches of the section have lacustrine diatomite layers as well as preserved logs, suggesting the presence of a wet, forested ecosystem as conformed by the structure of the paleosols. Climate data allow us to make analyses of large-scale ecological trends in mid-Miocene Oregon.
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Musser, Anne Marie School of Biological Earth & Environmental Sciences UNSW. "Investigations into the evolution of Australian mammals with a focus on monotremata." Awarded by:University of New South Wales. School of Biological, Earth and Environmental Sciences, 2005. http://handle.unsw.edu.au/1959.4/25739.
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This thesis began as an investigation into evolution of the platypus family (Ornithorhynchidae, Monotremata), now known from both Australia and South America. The thesis broadened its scope with inclusion of non-ornithorhynchid Mesozoic monotremes from Lightning Ridge, NSW. This change in direction brought an unexpected result: a fossil mammal from Lightning Ridge investigated for this thesis (presumed to be monotreme: Flannery et al., 1995) appears to be a new and unique type of mammal. Specimens were procured through Queensland Museum (Riversleigh material); Australian Museum (Lightning Ridge material); and Museum of Victoria and the South Australian Museum (fossil ornithorhynchids). Specimens were examined under a light microscope and scanning electron microscope; specimens were photographed using light photography and a scanning electron microscope; and illustrations and reconstructions were done with a camera lucida microscope attachment and photographic references. Parsimony analysis utilised the computer programs PAUP and MacClade. Major conclusions: 1) analysis and reconstruction of the skull of the Miocene platypus Obdurodon dicksoni suggest this robust, large-billed platypus was a derived northern offshoot off the main line of ornithorhynchid evolution; 2) the well-preserved skull of Obdurodon dicksoni shows aspects of soft anatomy previously unknown for fossil ornithorhynchids; 3) two upper molars from Mammalon Hill (Etadunna Formation, late Oligocene, central Australia) represent a third species of Obdurodon; 4) the South American ornithorhynchid Monotrematum sudamericanum from the Paleocene of Argentina is very close in form to the Oligocene-Miocene Obdurodon species from Australia and should be considered congeneric; 5) a revised diagnosis of the lower jaw of the Early Cretaceous monotreme Steropodon galmani includes the presence of two previously undescribed archaic features: the probable presence of postdentary bones and a meckelian groove; 6) morphological evidence is presented supporting a separate family Steropodontidae; and 7) analysis of new fossil material for Kollikodon ritchiei suggests that this taxon is not a monotreme mammal as originally identified but is a basal mammal with close relationships to allotherian mammals (Morganucodonta; Haramiyida). Kollikodon is provisionally placed as basal allotherian mammal (Allotheria sensu Butler 2000) and is unique at the ordinal level, being neither haramiyid nor multituberculate. A new allotherian order ??? Kollikodonta ??? is proposed.
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TOMIDA, YUKIMITSU. "SMALL MAMMAL FOSSILS AND CORRELATION OF CONTINENTAL DEPOSITS, SAFFORD AND DUNCAN BASINS, ARIZONA (GILA CONGLOMERATE, MAGNETOSTRATIGRAPHY, BIOCHRONOLOGY, BLANCAN AGE, TAXONOMY)." Diss., The University of Arizona, 1985. http://hdl.handle.net/10150/188105.
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Fossil bearing continental deposits, the Gila Conglomerate, of the Safford and Duncan Basins, Arizona were correlated with the magnetic polarity time scale by means of magnetostratigraphy and biochronology of mammalian fossils. Within the Safford Basin, the Bear Springs section with a middle Blancan fauna is correlated with the lower or upper Gauss chron; the 111 Ranch section with a middle to late Blancan fauna is correlated with the upper Gauss to early Matuyama chrons; and the San Simon Power Line section with probably a latest Blancan fauna is correlated with the early Matuyama chron. In the Duncan Basin, the Duncan section with a middle Blancan fauna is correlated with the middle Gauss chron; the Pearson Mesa section with a middle Blancan fauna is correlated with the Upper Gauss chron; and the Country Club section with a middle Blancan fauna is correlated with the latest Gilbert to early Gauss chrons or from the middle Gauss to the earliest Matuyama chrons. A late Blancan fauna is not recognized in the Duncan Basin at least within the study area, whereas the Gila Conglomerate in the Safford Basin includes deposits and fauna of the latest Blancan (latest Pliocene) age. A minimum of 37 taxa of small mammals are recognized among the approximately 1,600 specimens from the Gila Conglomerate of the Safford and Duncan Basins. Three new rodent species are described; they are Pappogeomys (Cratogeomys) sansimonensis, new species; Reithrodontomys galushai, new species; and Repomys arizonensis, new species. One new combination of genus and species, Hypolague virginiae, is described. In the Safford Basin, a minimum of 26 small mammal taxa are now recognized in the 111 Ranch fauna, of which three genera (Dipodomys, Peromyscus, and Repomys) are new records to the fauna; a minimum of 6 taxa of small mammals are recognized and described for the first time in the San Simon Power Line fauna. In the Duncan Basin, a minimum of 15 small mammal taxa are recognized and described for the first time.
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Van, Pletzen Liezl. "The large mammal fauna from Klasies River." Thesis, Stellenbosch : Stellenbosch University, 2000. http://hdl.handle.net/10019.1/51991.
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Thesis (MPhil)--University of Stellenbosch, 2000.ENGLISH ABSTRACT: The large mammal faunal sample, excavated since 1984 from the Late Pleistocene Klasies River main site, was studied. There are 27 species in eight genera represented. The bovids from the LBS member (110 000 years) and the Upper member (70 000 years) shows an increase in grazers relative to the fauna from the SAS member (100 000 years). This confirms previous research. The study of body part frequencies does not confirm the selective transport of the carcasses of larger bovids or that scavenging played an important role in the accumulation of the fauna. It is concluded that availability of marine mammals were the attraction of the locality and that all size classes of bovids were actively hunted and their carcasses returned to the site. KEYWORDS: Klasies River, Late Pleistocene, large mammal fauna, hunting.
AFRIKAANSE OPSOMMING: Die groot soogdier fauna van die Laat Pleistoseen vindplaas Klasies River main site, opgegrawe vanaf 1984, is bestudeer. Sewe-en-twintig spesies in agt genera is verteenwoordig. Die bokke van die LBS member (110 000 jare) en die Upper member (70 000 jare) toon 'n styging in grasvreters relatief tot dié van die SAS member (100 000 jare). Dit bevestig 'n vorige ondersoek. Die bestudering van ligaamsdeel frekwensies van alle groottes bokke bevestig nie dat selektiewe vervoer van groter bokkarkasse plaasgevind het nie, of dat aas 'n rol in die akkumulasie van die fauna gespeel het nie. Die gevolgtrekking is gemaak dat die teenwoordigheid van marine soogdiere die rede was vir die keuse van hierdie vindplaas was. Alle groottes bokke is doelbewus gejag en hulle karkasse is teruggebring na die vindplaas. SLEUTELWOORDE: Klasies River, Laat Pleistoseen, groot soogdiere, jag.
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Ribeiro, Graziella do Couto. "Osteologia de Taubatherium paulacoutoi Soria & Alvarenga, 1989 (Notoungulata, Leontiniidae) e de um novo Pyrotheria: dois mamíferos fósseis da Formação Tremembé, Brasil (SALMA Deseadense - Oligoceno Superior)." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/41/41133/tde-18012016-163320/.
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O presente estudo aborda a descrição osteológica e a análise taxonômica dos fósseis de Taubatherium paulacoutoi (ordem Notoungulata: família Leontiniidae) e de um novo táxon (ainda não descrito) da ordem Pyrotheria, ambos procedentes da Formação Tremembé (Bacia de Taubaté), com idade ao redor de 24 milhões de anos. A análise inclui todo material disponível, a maioria não estudada previamente. Comparações desses materiais foram feitas com esqueletos de mamíferos fósseis, das mesmas ordens e famílias de outras localidades da América do Sul de idade semelhante. A maioria dos fósseis procedentes da Fm. Tremembé, bem como os esqueletos de mamíferos atuaisencontram-senas coleções do Museu de História Natural de Taubaté (MHNT). Os fósseis procedentes de outros países sul-americanos foram examinados e analisados em coleções paleontológicas de museus da Argentina e dos Estados Unidos. Foram mais de 490 segmentos (dentes e ossos) analisados e referidos a T. paulacoutoi, sendo alguns fragmentados, mas outros praticamente completos e em ótimo estado de conservação. Com o objetivo de ampliar o conhecimento de Taubatherium paulacoutoi foi realizada a descrição anatômica e comparativa do esqueleto, bem como a reconstituição completa do esqueleto e do animal em vida, incluindo hábitos alimentares e postura corporal. Os resultados revelaram que Taubatherium é um mamífero de médio porte, com aproximadamente 1,80 m de comprimento, 80 cm de altura e cerca de 280-350 kg de peso, comparável em tamanho e massa corpórea a uma espécie moderna de Equus (Equidae), cujas características corroboram a hipótese de ter sido um mamífero herbívoro rameador, de hábitos gregários, que vivia em bandos à beira do paleolago. Para uma melhor caracterização do Pyrotheria da Formação Tremembé foram realizadas comparações dos dentes e dos ossos pós-cranianos com os de outros membros da família Pyrotheriidae, especialmente com Pyrotherium romeroi (Argentina) e Pyrotherium macfaddeni (Bolívia). A presença da ordem Pyrotheria foi confirmada para a Fm. Tremembé. Contudo, as características morfológicas observadas nos materiais o diferem dos táxons previamente descritos para a familia; o pirotério da Fm. Tremembé mostra semelhanças com os do gênero Pyrotherium, porém se trata, seguramente, de um gênero e de uma espécie distinta ainda a ser descrita. A paleomastofauna conhecida para a Bacia de Taubaté tem composição própria, representada por espécies endêmicas. Tais registros corroboram com a SALMA Deseadense Superior (Oligoceno Superior ou Mioceno Inferior) para a Fm. Tremembé, cujos depósitos representam um momento singular na história da América do SulThe present study comprises an osteological description and taxonomic analysis of fossil mammal remains of Taubatherium paulacoutoi (order Notoungulata: family Leontiniidae) and also of a new taxon (undescribed) of the order Pyrotheria, both from the Tremembé Formation (Taubaté Basin), aged around 24 mya. The analysis included all available material, most of which had not been studied previously. Comparisons were made with fossil mammals of the same orders and families of similar age from other localities in South America. Most fossil remains from Tremembé Formation and current mammalian skeletons are housed in the collections of Museu de História Natural de Taubaté (MHNT). Fossils from other South American countries were analyzed in paleontological collections from museums in Argentina and the United States.The studied material included more than 490 bone and teeth fossils referable to T. paulacoutoi, some of which were fragmented, but others almost complete and in excellent condition. We made a complete reconstruction of the skeleton, with anatomical and comparative descriptions, and propose body posture and likely eating habits. The results revealed that Taubatherium was a medium-sized mammal, around 1.80 m long, 80 cm high, and about 280-350 kg weight, comparable in size to the body mass of a modern Equus species (Equidae), and its features support the hypothesis of a herbivorous rameador mammal of gregarious habits that lived in herds around the paleo-lake. To characterize the new taxon of Pyrotheria from the Tremembé Formation, comparisons were made of teeth and post-cranial bones with other members of Pyrotheriidae, especially with Pyrotherium romeroi (Argentina) and P. macfaddeni (Bolivia). The presence of the order Pyrotheria in the Tremembé Formation is confirmed.However, the morphological characteristics observed in the fossil samples differ from all previously described taxa for the family; our fossil material from the Fm. Tremembé resembles the genus Pyrotherium, but is sufficiently distinct to warrant recognition as a new species in a distinct genus. The paleomastofauna known for the Taubaté Basin has a distinctive composition and is represented by endemic species. Such records corroborate with the SALMA Upper Deseadense (Upper Oligocene and Lower Miocene) at Fm. Tremembé, and these deposits represent a unique period in the history of South America
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Price, Catherine R. "Late Pleistocene and Early Holocene small mammals in South West Britain : environmental and taphonomic implications, and their role in archaeological research." Thesis, University of South Wales, 2001. https://pure.southwales.ac.uk/en/studentthesis/late-pleistocene-and-early-holocene-small-mammals-in-south-west-britain-environmental-and-taphonomic-implications-and-their-role-in-archaeological-research(0fdb87f2-abcf-4676-9bd3-0a23c9922caf).html.
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This project examines small mammal faunas from cave sites in south-west England and south Wales. The aims are threefold: To examine the rapid environmental changes taking place in the Late Pleistocene and early Holocene: To understand the processes by which small mammal remains were deposited in the caves examined: To demonstrate the value of small mammal studies as an archaeological tool. All identifiable small mammal remains from twelve selected sites are listed. Ten of the sites are new material. As the species examined here are seldom exploited by humans, the small mammals provide a record of the past environment unaffected by human selection of particular species, as might be the case in larger mammal assemblages. An examination of possible agents of accumulation is provided for each site to identify any bias introduced by prey selection. Reconstructions of the environment local to each cave at the time of deposition are offered. The evidence provided by the small mammals is related to the archaeological findings from each cave, to demonstrate the effect of human habitation of cave sites on the depositional and post-depositional processes shown by the microfauna. The environmental evidence provided by the study reflects a wider landscape rather than merely the immediate surroundings of the cave, and so gives a basis for human exploitation patterns in the area accessible from the cave. Reconstructions of the ecological mosaics formed by the rapidly changing climate of the period and the topographic variation around the cave sites are provided, demonstrating the potential complexity of the environment in which the humans and other fauna of the period existed. It is hoped that this will encourage archaeologists to look beyond the general division of environmental boundaries in this period, and to examine the local variation in habitat availability and use.
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Downing, Kevin Francis. "Biostratigraphy, taphonomy, and paleoecology of vertebrates from the Sucker Creek Formation (Miocene) of southeastern Oregon." Diss., The University of Arizona, 1992. http://hdl.handle.net/10150/185976.
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The Sucker Creek Formation exposures at Devils Gate in southeastern Oregon have yielded a significant small mammal fauna of at least thirty small mammal taxa from five stratigraphic horizons. The mammal-bearing portion of the Devils Gate section is more than 200 m thick. Fossil mammals occur in lacustrine and marginal lacustrine deposits lower in the section and occur in overbank and paleosol deposits higher in the section. ⁴⁰Ar/³⁹Ar single-crystal laser-fusion dates on three Devils Gate ashes shows that the age of the mammal-bearing sequence at Devils Gate spans the late early Barstovian land-mammal age with possible overlap into the late Barstovian, as currently defined. Duration of the entire mammal-bearing portion of the Devils Gate section was less than a million years. Both a new ash date from the type section and biostratigraphic correlations between Devils Gate and the type section support considerable temporal overlap between the two exposures. The Devils Gate Local Fauna includes several new taxa: a phyllostomatid bat; two "flying squirrels", Petauristodon sp. A and Petauristodon sp. B; and an eomyid rodent, Leptodontomys sp. A. Several fossil occurrences represent the first record of a taxon in the northern Great Basin and/or in the Barstovian land-mammal age, including: Blackia sp., Schaubeaumys grangeri, Protospermophilus quatalensis, and Pseudadjidaumo stirtoni. The Stagestop locality produced two new taxa, Copemys sp. aff C. esmeraldensis and Mystipterus sp. The Stagestop local fauna is Clarendonian in age. Concretions are an important source of fossil mammals in exposures of the Sucker Creek Formation. Geochemical analyses show that concretions formed through a complex interaction between bone and surrounding volcaniclastic material. Although some superficial bone was consumed during concretion diagenesis, concretion development reduced the chance of prolonged chemical and physical destruction of bone during later soil development. The broad ecological diversity of small mammals recovered from Devils Gate supports an interpretation of the local paleoecology as a mosaic of grassland, forest, and pond/lake-bank environments. Sequential small mammal faunas across a prominent ash event show a generally stable composition with no pronounced ecomorphic differences in pre- and post-volcanic disturbance intervals. Therefore, small mammals do not show analogous ecological patterns to disturbance-driven plant successions in the Sucker Creek Formation. I infer that the local ecosystem recovered from volcanic blasts at a temporal scale below the resolution of time-averaged, post-disturbance paleosols.
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Ribeiro, Graziella do Couto. "Avaliação morfológica, taxonômica e cronológica dos mamíferos fósseis da Formação Tremembé (Bacia de Taubaté), Estado de São Paulo, Brasil." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/41/41133/tde-15022011-104125/.
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Com base em novos fósseis de mamíferos coletados na Formação Tremembé, Bacia de Taubaté, Estado de São Paulo, Brasil e na reavaliação dos materiais anteriormente estudados e coletados nesta mesma localidade, é apresentado um panorama da paleomastofauna desta Formação. Foram feitas redescrições de materiais de alguns grupos, melhorando o conhecimento anatômico de alguns espécimes. A ampliação da diversidade conhecida de mamíferos fósseis deve-se a materiais inéditos coletados no afloramento da Fazenda Santa Fé (Tremembé) e depositados no Museu de História Natural de Taubaté (MHNT). As comparações foram feitas com materiais de outras localidades da América do Sul, de idade igual ou semelhante, que confirmam a identificação de diversos táxons, contribui com a reconstituição do paleoambiente e a determinação da idade dos sedimentos da Formação Tremembé. Três novos táxons de metatérios são reconhecidos, sendo dois deles representados por material de excelente valor diagnóstico. São reconhecidos um Proborhyaenidae de médio porte (no lugar de um suposto Borhyaenidae) e um Metatheria da família Hathliacynidae (próximo de Sipalocyon) de tamanho semelhante ao de um gambá atual (Didelphis). A presença de um material dentário de Pyrotheriidae, juntamente com material pós-craniano, também contribui com características diagnósticas de um táxon distinto de outros membros da família. O fragmento dentário até então identificado como de um Notohippidae indeterminado é aqui atribuído a Rhynchippus brasiliensis que, como Taubatherium paulacoutoi, parece ser uma espécie polimórfica quanto aos caracteres dentários. Com base em materiais dentários, Taubatherium paulacoutoi é o único Leontiniidae seguramente descrito para a Formação Tremembé. Entretanto, um novo material pertencente a esta família é aqui apresentado, porém com dados insuficientes para uma melhor identificação. Os materiais analisados reforçam, para a Formação Tremembé, a idade Deseadense Superior, ou ainda, sugerem idade Oligoceno Superior ou, com menor probabilidade, Mioceno Inferior, ou seja, ao redor de 23,5 a 24 milhões de anos. Os mamíferos colaboram também para reforçar a idéia de um paleoambiente ligado a uma região de beira de lago, com grande oferta de peixes, principalmente, durante as estações de estiagem, que atraía um grande número de animais oportunistas.This study presents a comprehensive panorama of the fossil mammal fauna of the Tremembé Formation, Taubaté Basin, São Paulo State, Brazil based on recently collected materials, and revaluation of previous specimens collected from the same fossil quarries. We improved our understanding of previously examined material by making new descriptions, and our appreciation of the diversity of fossil mammals in this area was further enhanced by studies on hitherto unpublished collections from outcrops at the Fazenda Santa Fé (Tremembé) that are now deposited in the Museu de História Natural de Taubaté (MHNT). Comparisons were made with fossil collections of the same or similar age from other localities in South America. The comparisons helped confirm the identity of diverse taxa, and contributed to a reconstruction of the palaeoenvironment, and to the determination of the age of the sediments in the Tremembé Formation. Three new Metatheria taxa were recognised, two of which were based on material with excellent diagnostic features: they comprise a medium sized Proborhyaenidae (previously identified as a supposed Borhyaenidae), and a Metatheria of the family Hathliacynidae (a close relative of Sipalocyon) that was similar in size to the recent opossum (Didelphis). A dental and also post-cranial material of the Pyrotheriidae provided diagnostic characters for a new taxon distinct from other members of the pyrotheriids. Another dental fragment previously identified as an undetermined Notohippidae, we attribute to Rhynchippus brasiliensis which, like Taubatherium paulacoutoi, seems to be a rather polymorphic species with regard to dental features. Taubatherium paulacoutoi is the only Leontiniidae that has been identified with confidence for Tremembé, and whilst we assign the new material to this family, the data are insufficient for a more positive identification. The analysed materials reinforce the view that the Tremembé Formation belongs to the Upper Deseadense, or perhaps the Upper Oligocene, or more unlikely the Lower Miocene, i.e. around 23.5-24 mya. These mammal fossils also support the idea of a palaeoenvironment that was a lakeside habitat, with the occurerence of many fish, mainly, in the dry season, that may have attracted a large number of opportunistic animals.
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Gilmour, Daniel McGowan. "Chronology and Ecology of Late Pleistocene Megafauna in the Northern Willamette Valley, Oregon." PDXScholar, 2011. https://pdxscholar.library.pdx.edu/open_access_etds/416.
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This study is an investigation of the timing of extinction of late Pleistocene, large bodied mammalian herbivores (megafauna) and of the environment in which they lived. The demise of the megafauna near the end of the Pleistocene remains unexplained. Owing to potential human involvement in the extinctions, archaeologists have been particularly concerned to understand the causes for faunal losses. Our current lack of understanding of the timing and the causes of the extinctions in North America may result from a deficiency in understanding the histories of each individual species of extinct animal on a local level. Detailed regional chronologies of fauna are necessary for comparison with paleoenvironmental and archaeological data to help sort out causes for extinction. The Willamette Valley of western Oregon has long been noted for finds of megafauna, though records have not been synthesized since the early 20th century and these materials have remained largely unstudied. In this thesis, I first create a catalog of extinct megafauna recovered from the Willamette Valley. Next, using material from the northern valley, I employ AMS radiocarbon dating, stable isotope δ¹³C and δ¹⁵N analyses, and gross inferences based on the dietary specializations and habitat preferences of taxa in order to reconstruct environments and to develop a local chronology of events that is then arrayed against archaeological and paleoenvironmental data. The results of this study indicate that megafaunal populations in the northern Willamette Valley were contemporaneous with the earliest known human populations of the Pacific Northwest, as well as later populations associated with the Clovis Paleoindian Horizon. Consistent with the overkill hypothesis, radiocarbon ages span the length of the Clovis window, but no ages are younger than Clovis. Moreover, all radiocarbon ages are older than or contemporaneous to the onset of the Younger Dryas Stadial. No age ranges fall exclusively within the Younger Dryas. Comparison of megafaunal ages and paleoenvironmental records support the view that climate change contributed to local animal population declines. Prior to ~13,000 cal BP, the Willamette Valley was an open environment; herbivores mainly consumed C₃ vegetation. The timing of the loss of megafauna coincides with increased forested conditions as indicated by regional paleoenvironmental reconstruction. As the timing of megafaunal decline correlates with Clovis, the onset of the Younger Dryas, and increased forested conditions, it is not possible with the data currently available to distinguish the cause of extinction in the Willamette Valley. The age ranges of the fauna coupled with taphonomic and geologic context indicate that the fauna are autochthonous to the Willamette Valley; they do not represent ice rafted carcasses or isolated skeletal elements transported from elsewhere during late Pleistocene glacial outburst floods.
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Clark, Sarah, and Joshua X. Dr Samuels. "Mammal Community Structure Analysis of the Gray Fossil Site, TN." Digital Commons @ East Tennessee State University, 2021. https://dc.etsu.edu/asrf/2021/presentations/63.
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The early Pliocene age Gray Fossil Site (GFS) was relatively recently found, with much still to be discovered and examined, and represents one of only a few sites of its age in eastern North America. It has been noted that the diverse faunal remains found at GFS are unique compared to what have been found at other fossil sites in North America from the same time period. Studying mammalian community structures at fossil sites can provide an abundance of information about the past environment and species adaptations to it, such as niche occupation of species, resource partitioning, and interactions between organisms and their environment. The main questions being asked in this study are: 1) what is the mammal community structure like at GFS?, and 2) how does the community structure at GFS compare to other contemporaneous sites? While studies of the fauna and flora have helped us to understand the ecosystem at GFS, detailed study of the mammal community will help us better understand this unique site. It is expected that the community structure and niche occupation of the mammals at GFS will be different from other contemporaneous sites, dominated by mammals adapted for life in the warm oak, hickory forest present at the site. A taxon-free approach to analysis will be used so that environments not sharing the same taxa or of different ages can be compared to one another. Each mammal species from GFS (48 total) and five well-known contemporaneous sites are categorized by body size, locomotor mode, and dietary preference to characterize the niches occupied by each species. Categorizations for each species will come from published works and measurements / ecomorphological analysis of specimens. Preliminary results show that GFS is different from other sites in that there are more brachyodont and tree dwelling/climbing adapted species present, and there are fewer running species present. The initial findings are likely associated with the site being a closed, forested ecosystem, compared to the more open environments of the other sites. Moving forward, descriptions pertaining to specifically how GFS and its mammal community structure compare to the niche occupation of similar species at other sites will be discussed. This project will also examine what more this analysis can reveal about the ecosystem at GFS, particularly how the herbivorous mammals can provide greater insight into what environmental conditions were like, including what vegetation was predominant at GFS.
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Iliopoulos, George. "The Giraffidae (Mammalia, Artiodactyla) and the study of the histology and chemistry of fossil mammal bone from the Late Miocene of Kerassia (Euboea Island, Greece)." Thesis, University of Leicester, 2003. http://hdl.handle.net/2381/35044.
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A taphonomic investigation of Late Miocene mammal bones and teeth and a taxonomic study of the abundant and diverse giraffid material from Kerassia, Greece, were undertaken. The material was collected from seven different sites near Kerassia, where at least two fossiliferous horizons occur. Microbial action caused extensive destruction in almost all the examined specimens of bone and teeth tissues from both horizons. Despite this, and contrary to the established ideas, bioeroded tissues survived to become fossils, preserving their histological and bioerosion features. The diameters of the microtunnels (150-600 nm) in the destructive foci indicate that the invading microorganisms were bacteria. Recrystallization of the apatite crystallites in the foci of damaged tissues occurred immediately after the end of bacterial activity, restraining later diagenetic recrystallization. This process is responsible for differences in the chemistry of the three structural areas of the bioeroded tissues, the undamaged areas, the foci and the rims of the foci. X-ray diffraction mineralogical analyses showed that fossil bone and dentine consist of carbonate fluorapatite and enamel consists of carbonate hydroxyapatite. The crystallinity of the fossil tissues is not age dependent but rather reflects the type of the hard tissue and the conditions of the local burial environment. To date, five different species of giraffes have been determined in Kerassia. Four species were found in the lower horizon, Palaeotragus rouenii, Palaeotragus sp., Samotherium major and Helladotherium duvernoyi and four species were found in the upper horizon Palaeotragus rouenii, Samotherium major, Helladotherium duvernoyi and Bohlinia attica. Finally, this study shows that a seasonal Mediterranean type, relatively temperate to warm and moist climate, can be inferred for the MN12 (Middle Turolian) of the Kerassia region.
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Sugawara, Mauro Toshiro Caiuby. "Diversification dynamics of Placentalia (Mammalia): integrating the fossil record with molecular phylogenies." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/41/41134/tde-26102015-165834/.
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The effects of intrinsic traits on the diversification dynamics have been extensively investigated, with several traits being associated with increase in diversification. On the other hand, the possible negative effects of traits on the diversification of a lineage have been for the most part overlooked. Here we used both the fossil record and molecular data to study the diversification dynamics of Placentalia, focusing on the orders in decline of diversity, and investigated different mechanisms that might control the evolutionary success of the 21 placental orders. More specifically we: 1- determined which of the 21 orders of Placentalia are in decline of diversity (i.e., Decline model); 2- investigated whether the Decline model has a phylogenetic signal; 3- tested the hypothesis that the differences in body size are related to the Decline model; 4- tested the hypothesis that the orders in Decline have lower morphological disparity; 5- investigated whether the orders in decline of diversity, inferred from the fossil record, are the ones with higher extinction risk nowadays. Our analysis indicate that the majority of the orders of placental mammals have a pattern consistent with the Decline model and, although the Decline model is not equally distributed among the placental superorders, there was no significant phylogenetic signal for the orders in diversity decline. We found a positive correlation between the Decline model and the average body size which is in line with previous studies on body size evolution. We argue that such results suggest a complex evolutionary dynamics: larger body size appears to be an evolutionary attractor with lineages showing a tendency to increase in size, however, the increase in body size would be counterbalanced by a higher propensity to Decline. Moreover, we found a the negative correlation between the Decline model and morphological variation. We suggest that such results could indicate two possible scenario: (i) the low morphological variation would cause lineages to loose diversity; (ii) the low morphological variation would be the product of decrease in diversity through extinction selectivity. Finally, we found no correlation between the extinction risk of extant species and the deep time diversity decline, which suggests that the drivers of the current and the past Decline are not the sameO efeito de caracteres intrínsecos na dinâmica de diversificação foram extensamente investigados e diversos caracteres foram associados com aumentos na diversificação. Contudo, os possíveis efeitos negativos de um caractere sobre a diversificação de uma linhagem foram em grande parte ignorados. No presente trabalho integramos o registro fóssil com dados moleculares para estudar a dinâmica de diversificação de Placentalia, focando nas ordens em declínio de diversidade, e investigamos possíveis mecanismos responsáveis por gerar os padrões de diversificação encontrados. Mais especificamente nós: 1- determinamos quais das 21 ordens de Placentalia estão em declínio de diversidade (i.e., Declínio); 2- investigamos se o Declínio apresenta um sinal filogenético; 3- testamos a hipótese de que o tamanho do corpo está relacionado com o Declínio; 4- testamos a hipótese de que as ordens em Declínio possum menor disparidade morfológica; 5- investigamos se as ordens em Declínio, inferido a partir do registro fóssil, são as mesas com maior risco de extinção na atualidade. Nossas análises indicam que a maioria das ordens de mamíferos placentários apresentam um signal consistente com o Declínio e, embora o Declínio não esteja igualmente distribuído entre as superorderns de Placentalia, não há um signal filogenético significativo para as ordens em Declínio. Nossos resultados indicam uma correlação positiva entre o Declínio e o tamanho corporal médio de cada ordem que está de acordo com estudos prévios sobre evolução do tamanho do corpo. Argumentamos que estes resultados sugerem uma dinâmica de evolução complexa: tamanho corpóreo grande seria um atrator evolutivo que gera a tendência das linhagens aumentarem de tamanho, todavia, o aumento do tamanho do corpo seria contrabalançado pela maior susceptibilidade ao Declínio. Outrossim, encontramos uma correlação negativa entre o Declínio e a variação morfológica. Argumentamos que essa correlação poderia indicar dois possíveis cenários: (i) a baixa variação morfológica seria responsável pela redução no número de linhagens e tornaria as ordens mais susceptíveis ao declínio de diversidade; (ii) a baixa variação morfológica teria sido gerada pela diminuição da diversidade. Por último, o risco de extinção das espécies atuais não está correlacionado com o Declínio, o que sugere que os mecanismos responsáveis pelo Declínio no passado e no presente não são os mesmos.
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Kitagawa, Hiromichi. "Taxonomic revision of the Pleistocene fossil Elephantidae (Mammalia, Proboscidea) from the Japanese and Taiwanese islands." 京都大学 (Kyoto University), 2011. http://hdl.handle.net/2433/142390.
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Doby, Joshua. "A Systematic Review of the Soricimorph Eulipotyphla (Soricidae: Mammalia) from the Gray Fossil Site (Hemphillian), Tennessee." Digital Commons @ East Tennessee State University, 2015. https://dc.etsu.edu/etd/2526.
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Due in part to the incompleteness of the Cenozoic fossil record in the eastern U.S., the evolution and immigration of shrews (Soricidae) is not well understood. A rich soricid fauna from the Gray Fossil Site (GFS), Washington County, TN, has enabled many new inferences to be made. There are 7 new species in 6 genera: Paenelimnoecus, “Blarinella”, Petenyia, Tregosorex, Crusafontina, and Gen et sp. nov. GFS species of the genera Paenelimnoecus, “Blarinella”, and Petenyia are the first occurrence of each genus in the New World. Tregosorex, Crusafontina, and the N.A. taxon Limnoecus all have their latest documented occurrence at the GFS, extending their temporal range by at least 1 million years. “Blarinella” sp. nov. has a complete lateral groove in the inferior incisor, providing the earliest evidence for venom in soricids by at least 4 million years. GFS taxa also provide insight into the evolution of both Soricini and Blarinini.
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Clifford, Andrew B. "Narial Novelty in Mammals: Case Studies and Rules of Construction." Ohio : Ohio University, 2003. http://www.ohiolink.edu/etd/view.cgi?ohiou1069445156.
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Abernethy, Aaron Randall. "Extreme Variation in the Sagittal Crest of Tapirus polkensis (Mammalia Perissodactyla) at the Gray Fossil Site Northeastern TN." Digital Commons @ East Tennessee State University, 2011. https://dc.etsu.edu/etd/1348.
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The preservation and quantity of fossil tapirs (Tapirus polkensis) from the Gray Fossil Site in northeastern Tennessee provides a unique opportunity for comparison and analysis of skeletal characters. Intraspecifically, modern tapirs show little to no variation in the morphology of the sagittal crest. However, several different morphologies exist within the sample at Gray. No osteological evidence of sexual dimorphism exists for tapirs, and no correlation between crest shape and sex was observed. Several juveniles display well defined crests, while some adults have only minor thickening of the temporal ridges; therefore, no distinct correlation between age and crest state could be established. Three different patterns of wear exist within the sample, but there is no correlation between these and crest morphology. No cranial pathologies were found to be associated with a crest type. Despite some correlations the sagittal crest could simply be a variable character due to intraspecific variation.
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Schubert, Anne Maria [Verfasser]. "Konstruktionsmorphologie hypsodonter Backenzähne bei rezenten und fossilen Rodentia (Mammalia) / Anne Maria Schubert." Bonn : Universitäts- und Landesbibliothek Bonn, 2019. http://d-nb.info/1190723190/34.
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Pujos, François. "Contribution à la connaissance des Tardigrades (Mammalia : Xenarthra) du Pléistocène péruvien : systématique, phylogénie, anatomie fonctionnelle et extinction." Paris, Muséum national d'histoire naturelle, 2002. http://www.theses.fr/2002MNHN0020.
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De nouveaux restes de Tardigrades ont été découverts dans les dépôts pléistocènes péruviens. Les Megatheriidae sont extrêmement diversifiés et deux nouvelles espèces du genre Megatherium font l'objet d'une étude anatomique détaillée. Une analyse phylogénétique des mégathères effectuée sur la base de 35 caractères crâniens et postcrâniens a été réalisée. Un nouveau paresseux singulier est également signalé. Ce mégalonychidé, présente une mosai͏̈que de caractères qu'il est inhabituel de retrouver associés chez un même paresseux et pourrait être mis en relation avec des aptitudes arboricoles. Une analyse phylogénétique préliminaire des Megatherioidea sur la base de 34 caractères crâniens et post-crâniens a été effectuée. Des études stratigraphiques et paléo-environnementales ont été réalisées dans trois sites de mammifères pléistocènes. Les fortes modifications du climat ainsi que l'intervention indirecte de l'homme a peut-être joué un rôle important dans l'extinction de ces mammifèresNew Tardigrada specimens have been discovered in Pleistocene deposits of Peru. Megatheriidae are extremely diversified and two new Megatherium species were described in detail. A megatheriine phylogenetic analysis has been performed on the basis of 35 cranial and postcranial characters. A new peculiar sloth is also reported. This Megalonychidae shows a mosaic of characters that is unusual to find associated a single in sloth species and could be related to arboreal habits. A preliminary phylogenetic analysis of Megatherioidea based on 34 cranial and postcranial characters was performed. Stratigraphical and paleoenvironmental studies were performed in three mammal bearing Pleistocene sites. Strong modifications of the climate and the indirect intervention of man may have played an important role in the extinction of these mammals
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Duvernois, Marie-Pascale. "Les Leptobos (mammalia, artiodactyla) du villafranchien d'Europe occidentale : systématique - Evolution - Biostratigraphie - Paléoécologie." Lyon 1, 1989. http://www.theses.fr/1989LYO10195.
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Le genre villafranchien leptobos est represente en asie par l. Falconeri (espece-type du genre) et en europe occidentale par plusieurs especes qui ont ete tres souvent confondues. Un bref historique retrace les diverses synonymies. Dans le present travail, leptobos a valeur de gendre et est considere comme appartenant a la sous-famille des bovinae en raison de ces caracteres craniens relativement evolues. Les especes europeennes sontau nombre de quatre, reparties en deux sous-genres representant deux lignees: 1) le sous-genre leptobos avec: leptobos elatus qui compte deux sous-especes, l. Elatus elatus et l. Elatus merlai, dont l. Stenometopon est un synonyme recent. Et qui contribue a caracteriser les biozones mnq 16 et 17; leptobos furtivus, qui remplace l. Elatus merlai des le debut de la zone 18; 2) le sous-genre smertiobos avec: leptobos bravardi qui est connu pendant une partie de la zone 16; leptobos etruscus dont l'extensin dans le temps va de la fin de la zone 16 au debut de la zone 20. L'apparition du genre leptobos coincide avec le debut du villafranchien. La repartition spatiotemporelle des especes eurpeennes contribue a confirmer l'unite faunique de l'europe occidentale durant le villafranchien. L'etude des faunes et des flores associees revele, pour les deux sous-genres, un environnement assez ouvert ou les zones a graminees et forestieres se juxtaposent. Leptobos est compare a des genres pliocenes: proleptobos, alephis et proamphibos, et a des genres pleistocenes: epileptobos, bibos, bos et bison. Proamphibos apparait comme un ancetre possible de leptobos l. L. Falconeri serait apparente a bibos et a epileptobos; le sous-genre leptobos pourrait etre lie avec bison (eobison); le sous-genre smertiobos n'aurait pas donne de descendant
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Crégut-Bonnoure, Evelyne. "Les ovibovini, caprini et ovini (Mammalia, Artiodactyla, Bovidae, Caprinae) du plio-pléistocène d'Europe occidentale : systématique, évolution et biochronologie." Lyon 1, 2002. http://www.theses.fr/2002LYO10001.
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Une analyse des caractères morphologiques et biométriques des Caprinae actuels (tribus des Ovibovini et des Caprini) et du Plio-Pléistocène d'Europe occidentale débouche sur de nouvelles interprétations et propositions taxonomiques et phylogénétiques. Pour les Ovibovini actuels, qui comprennent dans la plupart des classifications zoologiques les genres Ovibos et Budorcas, l'analyse des caractères permet d'exclure ce dernier de la tribu. Des analogies sont relevées entre les deux genres et Ovis, ce qui suggère une origine commune pour ces trois taxons. Le regroupement de Budorcas et d'Ovis dans la nouvelle tribu des Ovini est proposé. Pour Ammotragus et les Caprini actuels représentés par les genres Hemitragus, Pseudois et Capra, les caractères morphologiques et biométriques montrent que les trois premiers sont apparentés, Ammotragus étant toutefois plus à part. De nombreuses similitudes entre Hemitragus et Capra sont aussi décelables. Chez ce dernier, la quasi-identité de proportions et le peu de différences anatomiques entre C. Nubiana et C. Walie indiquent que le bouquetin d'Abyssinie ne constitue qu'une sous-espèce de celui de Nubie, et qu'il convient donc de la nommer C. Nubiana walie. La monophylie de C. Pyrenaica et C. Ibex, suggérée récemment par des analyses moléculaires, n'est confirmée ni par l'anatomie externe et interne, ni par la parasitologie qui distinguent à un niveau spécifique les deux taxons et montrent une certaine proximité entre C. Pyrenaica et C. Caucasica. La révision et l'étude des Ovibovini, Caprini et Ovini provenant d'environ 200 gisements compris entre la fin du Pliocène et le début de l'Holocène permettent de préciser les modalités de leur mise en place, leur origine et leur évolution. Sept genres (Megalovis, Soergelia, Praeovibos, Ovibos, Ovis, Hemitragus, Capra) et seize espèces sont reconnues (M. Latifrons, S. Minor, S. Brigittae, S. Elisabethae, P. Mediterraneus, P. Cedrensis, C. Ibex, C. Caucasica, C. Pyrenaica). Des néodiagnoses sont proposées et des rectifications de déterminations sont apportées, notamment pour les taxons du Pliocène et du Pléistocène inférieur attribués jusqu'ici à Capra. De nouvelles formes sont définies (P. Priscus delumleyi, C. Caucasica praepyrenaica) ainsi qu'un nouveau genre (Pseudocapra). Pour Capra, en France, le rôle de barrière filtrante joué au Pléistocène par le Rhône et la Durance est clairement montré. La présence de C. Caucasica est aussi confirmée, ainsi que sa nature d'ancêtre de C. Pyrenaica. L'influence de la loi de Bergmann chez Praeovibos et Hemitragus est visible, comme le sont les modifications engendrées par les isolats géographiques chez Capra. Deux phases principales d'immigration des Caprinae sont mises en évidence au début du Pliocène final et au début du Pléistocène moyen, ainsi qu'un appauvrissement progressif de la diversité des taxons. La durée de vie de chaque espèce peut être précisée et une nouvelle répartition chronologique et géographique en découle
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Gerwitz, Andrew. "Evaluating potential growth strategies using bone histology in Pleistocene-Holocene Odocoileus virginianus (Mammalia) from Florida." Kent State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=kent1470322817.
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Carroll, Beth R. "Form and Function of the Limbs of Hegetotheriine Notoungulate Hemihegetotherium trilobus from the Middle Miocene of Quebrada Honda, Bolivia." Case Western Reserve University School of Graduate Studies / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=case155430404598344.
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Berthet, Didier. "Le genre Cainotherium (Mammalia, Artiodactyla) : étude morphométrique, révision systématique, implications évolutives et paléobiogéographiques, extinction." Lyon 1, 2003. http://www.theses.fr/2003LYO10067.
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Le Cainotherium, artiodactyle endémique de l'Europe occidentale, est fréquemment trouvé dans les gisements de l'Oligocène supérieur (MP28) au Miocène moyen (MN6). Ses restes, souvent peu abondants, rendent alors la détermination difficile, car les nombreuses espèces décrites sont très mal caractérisées. L'étude morphométrique dentaire de populations abondantes récemment récoltées a permis de cerner le polymorphisme intraspécifique et d'aborder la définition des espèces. La grande monotonie des caractères dentaires de celles-ci au cours du temps est confirmée : la distinction des espèces se fait principalement sur des critères de taille et de rapports inter-dentaires. Un schéma phylogénétique, utilisant la distribution géographique et temporelle, est proposé ; il met en évidence une relation entre spéciation et crise. Des renseignements sur les traits de vie de Cainotherium sont fournis par le matériel post-crânien et les causes possibles de leur extinction sont passées en revue.
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Delmer, Cyrille. "Les premières phases de différenciation des Proboscidiens (Tethyria, Mammalia) : le rôle du Barytherium grave de Lybie." Paris, Muséum national d'histoire naturelle, 2005. http://www.theses.fr/2005MNHN0043.
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Cette thèse consiste en la description de vastes collections inédites attribuées au genre énigmatique Barytherium, provenant de Dor El Talha, Libye. Attribués à l'unique espèce connue du genre, B. Grave, ces spécimens ont permis la mise en évidence d'un fort dimorphisme sexuel chez ce taxon, lié au développement massif des incisives chez les mâles. Par ailleurs, B. Grave, bien qu'étant le plus ancien proboscidien de taille comparable à celle des éléphants actuels, présente une morphologie et une posture très différente de la morphologie graviportale partagée par tous les éléphantiformes. Ses membres présentent en effet une angulation nettement marquée, avec des autopodes plantigrades et pseudo-sériés. Une analyse phylogénétique incluant 226 caractères anatomiques appliqués à tous les téthythères primitifs confirme la position basale des proboscidiens primitifs lophodontes stricts, la ressemblance morphologique entre le genre Moeritherium et les siréniens apparaissant issue de convergenceIn this thesis, significant and unpublished collections referred to the enigmatic genus Barytherium found in Dor El Talha are described. Identified as B. Grave, the only species currently described in this genus, the study of these specimens led to the identification of a strong sexual dimorphism within this taxon, related to the enlargement of the incisors of the males. More over, B. Grave, although being the oldest proboscidean of similar size than extant elephant, does not show the graviportal stance shared by all elephantiforms. The angulation of its limbs appears indeed much more significant, while its autopodes show a plantigrade a pseudo-seriated disposition. A phylogenetic analysis including 226 anatomical characters controlled on all early tethytheres confirms the basal position of the lophodont early proboscidieans, the morphological resemblances between the genus Moeritherium and the sirenians being regarded as convergent
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Mercer, Lonnie T. "Geology of the Tierras Blancas Area in the Southeastern Acambay Graben, Central Mexico." BYU ScholarsArchive, 2005. https://scholarsarchive.byu.edu/etd/303.
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Pliocene-Pleistocene sediments in the southeastern Acambay graben, central Mexico have yielded mammal fossils, including Equus simplicidens, cf. Rhynchotherium, ?Camelops, Mammuthus sp., Bison sp., and Antilocapra sp. The fossiliferous sediments include a period of lacustrine sedimentation in the late Pliocene-early Pleistocene that interrupted fluvial and alluvial sedimentation during the early Pliocene and Pleistocene. The sediments deposited in this late Pliocene paleolake record a history of lake level fluctuations, shown by lithologic variations in lacustrine sediments and abundance of vertebrate burrows. Volcanic and tectonic events in the Acambay graben were the major controls on sedimentation during Pliocene-Pleistocene time. Various local volcanic structures produced source rocks for Pliocene-Pleistocene sediments, and intra-arc extensional tectonics caused basin subsidence. Blockage of stream drainages by lava flows or perhaps increased basin subsidence contributed to the appearance of and fluctuations in the lacustrine system during the late Pliocene. Diatom assemblages from lacustrine sediments indicate slightly higher precipitation and humidity than present-day conditions in the Acambay graben. Therefore, climatic forcing may have also contributed to the development of the late Pliocene paleolake in the Acambay graben. Pliocene-Pleistocene volcanic rocks in this part of the Acambay graben range from basaltic andesite to rhyolite. The calc-alkaline composition of these volcanic rocks is similar to others in the modern Mexican Volcanic Belt; they have a continental arc affinity, which is consistent with a tectonic setting within the Mexican Volcanic Belt. The major eruptive episode in the Acambay graben occurred during the early Pliocene, although volcanism, represented by small volcanic structures, continued until the late Pleistocene. This observed decline in volcanism in the Acambay graben correlates with a early Pliocene through Quaternary trenchward migration of volcanism in the Mexican Volcanic Belt.
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Muizon, Christian de. "Les odontocetes ( cetacea, mammalia) du neogene de la formation pisco (perou) : phylogenie et taxonomie des odontocetes fossiles et actuels." Paris 7, 1987. http://www.theses.fr/1987PA077255.
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On etudie les odontocetes de la formation pisco, perou. Les formes pliocenes proviennent en majeure partie du gisement de sud sacaco alors que les formes miocenes proviennent d'aguada de lomas, d'el jahuay, de cerro la bruja et de santa rossa. L'etude de detail permet la reconnaissance de nouveaux genres et de nouvelles especes et de reviser la phylogenie et la taxinomie de tous les groupes d'odontocetes fossiles et actuels, et de preciser le polyphyletisme des dauphins de riviere (platanistoidea). Toutes les donnees utiles concernant le genre considere, son espece-type et le specimen-type sur lequel elle est fondee sont repertoriees dans un catalogue des odontocetes fossiles
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Jourdain, de Muizon Christian. "Les Odontocètes (Cetacea, Mammalia) du néogène de la formation Pisco (Pérou) phylogénie et taxonomie des odontocètes fossiles et actuels /." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37606294j.
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Metz-Muller, Florence. "La population d'Anancus arvernensis (Proboscidea, Mammalia) du Pliocène de Dorkovo (Bulgarie) : étude des modalités évolutives d'Anancus arvernensis et phylogénie du genre Anancus." Paris, Muséum national d'histoire naturelle, 2000. http://www.theses.fr/2000MNHN0018.
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Bachelet, Bernadette. "Muridae et Arvicolidae (Rodentia, Mammalia) du Pliocène du sud de la France : systématique, évolution, biochronologie." Montpellier 2, 1990. http://www.theses.fr/1990MON20299.
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Cinq nouvelles localites karstiques d'age pliocene, riches en micromammiferes et particulierement en rongeurs, ont ete decouvertes en languedoc et en roussillon. Les faunes de rongeurs recoltees permettent le reexamen de celles deja connues dans cette region. L'etude des stephanomys a l'echelle de l'espagne et du sud de la france a conduit a l'identification d'une nouvelle lignee de ce genre au cours du pliocene. Le reexamen des petits mimomys de ces deux memes secteurs geographiques permet une nouvelle definition de l'espece m. Stehlini et une reinterpretation d'une partie du schema evolutif propose pour la lignee m. Occitanus-m. Savini. Se fondant sur ces analyses phyletiques, le cadre biochronologique du pliocene du sud de la france a pu etre affine et des correlations avec l'espagne etablies. Une nouvelle methode estimant l'age numerique d'un gisement a partir de l'utilisation des lignees evolutives est proposee. Elle a permis le calcul des taux de transformation morphologique des lignees et d'analyser les evenements fauniques a l'echelle de l'espece et la dynamique de la faune de rongeurs. Les principaux evenements fauniques reperes entre 5 et 2,3 ma coincident avec les deux variations paleoclimatiques importantes enregistrees au pliocene
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Romaggi, Jean-Paul. "Les antilopes du miocène supérieur du Coiron (Ardèche, France) : monographie, phylogénie, dimorphisme sexuel des principaux Boselaphini (Bovidae, Mammalia) du miocène supérieur de l'Europe occidentale." Lyon 1, 1987. http://www.theses.fr/1987LYO10013.
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Monographie des boselaphini de la montagne d'andance. Description d'une nouvelle espece: graecoryx andancensis. L'existence d'un squelette de femelle gravide permet de demontrer que graecoryx est la femelle de tragocerus. Classification des boselaphini du neogene d'europe occidentale en tenant compte des nouvelles donnees sur le dimorphisme sexuel. Mise en evidence des tendances evolutives. Etude des exigences ecologiques et signification climatique du genre graecoryx
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Sagne, Claire. "La diversification des siréniens à l'Eocène (Sirenia, Mammalia) : étude morphologique et analyse phylogénétique du sirénien de Taulanne, Halitherium taulannense." Paris, Muséum national d'histoire naturelle, 2001. http://www.theses.fr/2001MNHN0036.
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A la fin de l'Eocène, la mer nummulitique de la Téthys centrale inonde la région des Alpes de Haute-Provence (France). Le gisement priabonien de Taulanne, associé à cette transgression, constitue un milieu de vie calme et peu profond, à proximité du littoral. Il a livré des restes abondants et variés d'un nouveau dugongidé (Mammalia, Sirenia, Dugongidae, Halitherium taulannense), accumulés dans plusieurs niveaux. L'étude exhaustive de sa morphologie, avec notamment des séries de croissance allant du nouveau-né à l'adulte âgé, peut être dès lors confrontée aux variabilités individuelle et ontogénétique des siréniens actuels (lamantins, dugongs). Ce sirénien est ensuite replacé dans son contexte systématique. Les données morphologiques sont soumises à une analyse cladistique (de parcimonie). 78 caractères anatomiques sont décrits, illustrés, puis controlés chez 30 siréniens. D'après l'arbre de consensus strict qui en résulte, le sirénien de Taulanne s'insère au-dessous du noeud dont est issu H. Schinzii (Europe, Oligocène), espèce type du genre. En outre, cette analyse permet : 1) de proposer un statut phylogénétique à sept siréniens dont c'est ici la première analyse cladistique, 2) de soutenir deux hypothèses de mise en synonymie de siréniens éocènes, 3) de conforter l'hypothèse de Savage (1977) selon laquelle les lamantins modernes émergent de siréniens éocènes, les protosirénidés. Ainsi, la dichotomie 'lamantins-dugongs' est estimée plus ancienne que ce que l'on pensait jusqu'à présent (analyse cladistique de Domming, 1994) et les deux familles monophylétiques Dugongidae et Trichechidae sont redéfinies.
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Bronnert, Constance. "Origine et premières dichotomies des Périssodactyles (Mammalia, Laurasiatheria) : apport des faunes de l'Éocène inférieur du bassin de Paris A primitive perissodactyl (Mammalia) from the early Eocene of Le Quesnoy (MP7, France) First European ‘Isectolophidae’ (Mammalia, Perissodactyla): Chowliia europea, sp. nov., from the lower Eocene of Le Quesnoy, France." Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUS563.
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Les périssodactyles (comprenant aujourd’hui les chevaux, les rhinocéros et les tapirs) apparaissent au début de l’Éocène et se dispersent rapidement dans tout l’hémisphère Nord. Leur origine géographique, probablement asiatique, ainsi que leur origine phylogénétique est actuellement débattue. Ce travail présente une étude et une révision des périssodactyles hippomorphes de l’Éocène inférieur (MP7-MP10) d’Europe, ainsi qu’une nouvelle phylogénie pour tenter de répondre à ces questions. La majorité du matériel est inédite et provient du bassin de Paris, ainsi que du sud de la France. Douze espèces d’hippomorphes, dont deux nouvelles, et une nouvelle espèce d’isectolophidé ont été identifiés dans l’Éocène inférieur d’Europe. Les faunes rapprochés du MP7 présentent des différences entre le nord et le sud de l’Europe, confirmant l’hypothèse d’une barrière climatique. Un renouvellement des périssodactyles au niveau générique s’effectue entre les sites rapprochés du MP7 et ceux rapprochés du MP8-9, ainsi qu’une homogénéisation des espèces entre le nord et le sud de l’Europe. Les sites MP8-9 et ceux proches du MP10 possèdent des faunes de périssodactyles similaires. L’étude phylogénétique indique que les hippomorphes européens sont paraphylétiques, et que les équidés nord-américains s’enracinent dans ce groupe, ainsi que les paléothères européens. Plusieurs évènements de dispersions ont eu lieu très tôt à l’Éocène depuis l’Asie. Deux épisodes de dispersions vers l’Europe ont eu lieu pour les tapiromorphes, un premier (MP7) amenant les isectolophidés qui s’éteindront rapidement en Europe, et un second (MP8-9) apportant des tapiromorphes plus dérivésPerissodactyls (nowadays including horses, rhinos and tapirs) appear at the beginning of the Eocene, and quickly spread into the whole Northern Hemisphere. The center of origin is still debated but the Asian hypothesis is favored, and their phylogenetic affinities are also matter of debate, mostly since the discovery of cambaytheres in India and the genetic affinities with the South American Native Ungulates. This work provides a review of hippomorph perissodactyles of the early Eocene (MP7- MP10) of Europe, and presents a new phylogeny to answer the question of their origin. Most of the material is unpublished and comes from the Paris Basin, as well as Southern France. Twelve hippomorph species, including two new species, and a new species of isectolophid have been identified for the early Eocene of Europe. Faunas close to the MP7 reference-level show differences between Northern and Southern Europe, confirming the hypothesis of a climatic barrier. A turnover of perissodactyls at the generic level takes place between the sites close to MP7 and those close to MP8- 9, and a homogenization of species between Northern and Southern Europe occurs. The sites close to MP8-9 and MP10 have similar perissodactyl faunas. The phylogenetic study indicates that European hippomorphs are paraphyletic, and that North American equids are rooted in this group, as well as European paleotheres. Several dispersal events occurred from Asia very early in the Eocene. Two episodes of dispersions towards Europe took place for the tapiromorphs, a first (MP7) bringing the isectolophids which will go extinct quickly in Europe, and a second one (MP8-9) bringing more derived tapiromorphs
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Schmitt, Arnaud. "La région de l’oreille osseuse chez les Proboscidea (Afrotheria, Mammalia) : anatomie, fonction, évolution." Thesis, Paris, Muséum national d'histoire naturelle, 2016. http://www.theses.fr/2016MNHN0011/document.
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Les éléphants font partie des rares mammifères capables d’entendre les infrasons et leur comportement locomoteur est unique. Ces singularités correspondent à des spécialisations de leurs organes sensoriels contenus dans l’oreille interne : la cochlée (audition) et le système vestibulaire (locomotion). Alors que la diversité actuelle des proboscidiens est très faible (trois espèces), ce groupe a été bien plus diversifié pendant les 60 millions d’années qui composent son histoire. Cette thèse étudie pour la première fois de façon complète la morphologie et la fonction de la région de l’oreille (périotique, labyrinthes osseux et membraneux) d’éléphants actuels grâce aux techniques CT scan 3D. De plus, les périotiques de quatorze genres de proboscidiens fossiles sont décrits afin de documenter l’évolution de ce complexe anatomique au sein de cet ordre de mammifères. Les résultats montrent que certains caractères de l’oreille sont très variables au niveau spécifique. Notre analyse inclut les plus anciens proboscidiens connus et suggère que la morphologie de la région otique a évolué graduellement pendant la première moitié de l’histoire évolutive du groupe et que le morphotype moderne éléphantin est déjà acquis chez les Deinotheriidae et généralisé chez les éléphantimorphes. Les inférences sur la locomotion et l’audition des taxons fossiles confirment ces observations. Ce travail permet ainsi de lever le voile sur l’évolution d’une région anatomique majeure, jusque-là méconnue chez un groupe emblématique de mammifèresElephants are among the few mammals able to hear infra-sounds, and they display a unique locomotor behavior. It corresponds to specializations of their sensory organs contained in the inner ear: the cochlea (audition) and the vestibular system (spatial orientation). While only three species are living today, they were a much more diverse group found in five continents and with a 60 Ma-long history. We provide here the first comprehensive morphological and functional study of the ear region (petrosal, bony and membranous labyrinths) of extant elephants using 3D CT scan techniques. Additionally, we describe and compare the petrosals of fourteen extinct proboscidean genera in order to shed light on the evolution of this anatomical complex in the Proboscidea. The results show that some features of the petrosal and bony labyrinth of extant elephants - such as the number of turns of the cochlea – display a noticeable level of intra-specific variability. Our analysis includes the earliest-known proboscideans and suggests that the petrosal and bony labyrinth morphology evolved gradually during the first half of the proboscidean evolutionary history, but also that the modern morphotype exhibited in elephants was probably already acquired in deinotheriids and generalized in elephantimorphs. Functional inferences on the locomotor behavior and the audition of extinct proboscideans confirm these observations. This work hence provides new insights on the evolution of a major anatomical region hitherto poorly known in an emblematic group of mammals
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Benoit, Julien. "Evolution des caractères crâniens et endocrâniens chez les Afrotheria (Mammalia) et phylogénie du groupe." Phd thesis, Université Montpellier II - Sciences et Techniques du Languedoc, 2013. http://tel.archives-ouvertes.fr/tel-01001999.
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L'étude des caractères basicrâniens et endocraniens chez les vertébrés fossiles et actuels connait un regain d'intérêt depuis quelques années. Ces caractères bénéficient en effet d'une bonne réputation en tant que marqueurs phylogénétiques, ainsi que d'un biais taphonomique favorable à leur fossilisation. C'est pourquoi dans ce volume, la région auditive et l'oreille interne (Partie I) et l'endocrâne (Partie II) de mammifères fossiles appartenant au clade des Afrotheria ont été scannés par (micro)tomographie à rayon-X, décrits, étudiés et comparés à ceux des espèces actuelles. Il s'agit plus précisément des Afrotheria fossiles que sont les Bibymalagasia (Chapitre 1), le Macroscelididae Chambius (Chapitre 2), de nombreux Hyracoidea du Paléogène (Chapitre 3) ainsi que des Tethytheria basaux tels que le proboscidien Numidotherium, l'embrithopode Arsinoitherium et le sirénien Prorastomus (Chapitre 4). Cette étude met en lumière l'intéressant signal phylogénétique fournit par les caractères de la région auditive et de l'endocrâne, capable de soutenir certains clades moléculaires (e.g. Afroinsectivora, 'Panelephantulus'). Elle montre aussi comment, sous certaines pressions de sélection, ces caractères peuvent converger de façon remarquable (e.g. chez les téthythères). Cette étude apporte aussi des éléments qui appuient l'hypothèse d'une origine Africaine des Afrotheria, ainsi que celle faisant de l'ancêtre commun des afrothères un mammifère plutôt 'ongulé' que 'insectivore'. Ces inférences fondées sur l'observation des représentants fossiles les plus anciens de ce groupe sont importants pour notre compréhension de l'origine et de la diversification des afrothères et des mammifères placentaires en général.
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Bouetel, Virginie. "Les “Cetotheriidae” (Mammalia, Cetacea, Mysticeti) de la Formation Pisco (Miocène inférieur – Pliocène inférieur) de la côte péruvienne : Relations phylogénétiques et affinités des “Cetotheriidae”." Paris, Muséum national d'histoire naturelle, 2005. http://www.theses.fr/2005MNHN0017.
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Les mysticètes à fanons comprennent généralement quatre familles actuelles et une famille fossile: les Cetotheriidae s. L. Dépourvus des synapomorphies des mysticètes actuels, ces fossiles sont un groupe paraphylétique peu étudié. La description de trois nouveaux taxons fossiles (Piscobalaena nana et deux nouveaux genres) de la Formation Pisco (Néogène, Pérou) a mis en évidence de nouveaux caractères morphologiques. Les Balaenopteridae ont une stratégie de nutrition très particulière à laquelle sont associés des caractères morphologiques du crâne et du dentaire. Six taxons fossiles présentent certains de ces caractères. Ils pourraient donc être phylogénétiquement proches des ces derniers et avoir utilisé la même stratégie nutritionnelle. L'analyse cladistique de 54 caractères (crâne, région auditive et dentaire) de 25 taxons suggère que huit des 15 taxons fossiles étudiés forment un clade : les Cetotheriidae s. S. Son groupe-frère comprend les taxons actuels et cinq fossilesBaleen mysticetes traditionally comprise four living families and a fifth exclusively fossil family: the Cetotheriidae s. L. . New material (Piscobalaena nana and two new genera) from the Neogene Pisco Formation of Peru, yield new morphological data. Balaenopteridae have a peculiar feeding behaviour associated with some morphological characters of the skull and dentary. Six fossil taxa present similar morphologies. Thus they could be phylogenetically close to Balaenopteridae and could have used the same feeding behaviour. The cladistic analysis of 54 characters (skull, auditory area, dentary) of 25 taxa suggests that eight of the 15 studied Cetotheriidae s. L. Constitute a clade: the Cetotheriidae s. S. Its sister-group includes the extant taxa and five fossil taxa
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Ladevèze, Sandrine. "La région auditive des Métathériens (Mammalia, Metatheria) du tertiaire inférieur d'Amérique du sud : Incidence sur l'origine phylogénétique et la systématique des Notometatheria (Métathériens d'Australie et d'Amérique du sud." Paris, Muséum national d'histoire naturelle, 2005. http://www.theses.fr/2005MNHN0049.
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Les gisements paléocènes de Tiupampa (Bolivie) et Itaboraí (Brésil) sont d'une importance majeure dans la compréhension de l'histoire évolutive des Notometatheria car ils représentent les plus anciens assemblages de métathériens sud-américains. Ils ont délivré de nombreux restes dentaires ainsi que des crânes et des périotiques isolés qui sont ici décrits. Des études morphométriques montrent une corrélation des proportions des molaires et du périotique, cependant l'attribution d'un périotique à un taxon défini par des dents demeure difficile. Des analyses de parcimonie menées sur des caractères dentaires, crâniens et de la région auditive concluent à deux scenarii : (i) les Notometatheria auraient divergé de taxons laurasiatiques vers la fin du Crétacé; (ii) les "Notometatheria" seraient polyphylétiques, et une différentiation précoce du groupe paraphylétique des "borhyaenoïdes" serait survenue avant la divergence des métathériens du Crétacé laurasiatique des autres "notométathériens"Paleocene layers from Tiupampa (Bolivia) and Itaboraí (Brazil) are of a main importance in the understanding of the Notometatheria evolutionary history, since they provide the most abundant and the oldest metatherian assemblage of South America. They have yielded many dental remains as well as skulls and isolated petrosals, which are here described. Morphometric studies show that molars proportions are correlated with that of petrosals; however, the assignation of a petrosal to a dental-based taxon remains difficult. Parsimony analyses were conducted on dental, cranial and petrosal characters. Two hypotheses clash: (i) Notometatheria would have diverged from North American and Asiatic taxa towards the late Cretaceous; (ii) "Notometatheria" would be polyphyletic, and an early differentiation of the paraphyletic "borhyaenoids" would have occurred before the divergence of cretaceous laurasiatic metatherians and the other "notometatherians"
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Lyons, Sara Kathleen. "A quantitative assessment of the community structure and dynamics of Pleistocene mammals /." 2001. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:3019946.
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Rankin, Brian Daniel. "Early late Paleocene mammals from the Roche Percée local fauna, southeastern Saskatchewan, Canada." 2009. http://hdl.handle.net/10048/773.
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Thesis (M.Sc.)--University of Alberta, 2009.Title from PDF file main screen (viewed on Apr. 1, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science in Systematics and Evolution, Department of Biological Sciences, University of Alberta. Includes bibliographical references.
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Macrini, Thomas Edward 1975. "The evolution of endocranial space in mammals and non-mammalian cynodonts." 2006. http://hdl.handle.net/2152/13066.
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Croft, Darin A. "Archaeohyracidae (mammalia: Notoungulata) from the Tinguiririca fauna, Cetranl Chile, and the evolution and paleoecology of South American mammalian herbivores /." 2000. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:9965069.
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Muchlinski, Magdalena Natalia 1978. "Ecological and morphological correlates of infraorbital foramen size and its paleoecological implications." 2008. http://hdl.handle.net/2152/17887.
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The infraorbital nerve (ION) transmits sensory information from mechanoreceptors of the upper lip and vibrissae (whiskers) to the brain via the infraorbital foramen (IOF). Vibrissae are special sensory hairs used by mammals to explore their surroundings. Researchers have used the size of the IOF to infer vibrissa count, which in turn has been incorporated into phylogenetic and ecological interpretations of fossil taxa. However, these interpretations are based on untested assumptions linking IOF size, ION size, vibrissae, and ecology. The purpose of this dissertation is to determine the functional significance of IOF size and to apply the results to the fossil record. It is hypothesized that ecological differences among mammals affects maxillary mechanoreceptivity (touch sensitivity of the rostrum), and that IOF area may be used as a measure of maxillary mechanoreceptivity. Three questions are posed to appraise this hypothesis: (1) Does IOF area correlate with ION area and vibrissa count? (2) How do the IOFs of primates differ from those of other mammals? (3) How do diet, substrate preference, and activity pattern affect IOF size? IOF area, ION area, and vibrissa count were collected from cadaver of extant mammals as well as museum osteological specimens. Results indicate that: (1) IOF and ION areas show a strong positive correlation. Based on this finding, it is hypothesized that IOF area may be a good measure of maxillary mechanoreception. (2) Vibrissae count significantly correlates with IOF area. (3) Euarchontans have relatively smaller IOFs than most other mammals. (4) The IOFs of primates co-vary with diet, where frugivores have relatively larger IOFs than both insectivores and folivores. Infraorbital foramen areas of 14 adapoid, six omomyoid, and 15 plesiadapiform species were measured. Two questions were addressed: (1) Do the sampled fossils share a similar reduction in IOF area to extant primates? (2) Do extinct frugivores have larger IOFs than insectivores and folivores? Results show that, adapoids and omomyoids have relatively small IOFs similar to euarchontans, but plesiadapiforms retain larger IOFs, comparable to most non-euarchontan mammals. Dietary analyses indicate that both frugivorous adapoids and omomyoids have larger IOFs than both insectivorous and folivorous species.text
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Estraviz, López Darío. "Quaternary fossil vertebrates from continental Portugal: Paleobiodiversity, revision of specimens and new localities." Master's thesis, 2019. http://hdl.handle.net/10362/74150.
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The Quaternary fossil record of Portugal is important for our understanding of the paleobiodiversity in Iberia. In the present master thesis a series of studies augment our knowledge about this topic. A census of Quaternary paleobiodiversity is carried out in order to test how reliable the fossil record is for detecting living species, resulting in that ~38% of living terrestrial tetrapods are recognized in the fossil record for Portugal, although the number of species recognized varies between groups. The body mass of a Portuguese proboscidean (Palaeoloxodon antiquus) is calculated via numerical methods for the first time (11metric tons) and morphometric comparisons of this species with Mammuthus primigenius are presented using an extensive Proboscidean sample. A new fossil brown bear (Ursus arctos) locality, Algar do Vale da Pena, with numerous claw mark in the walls of the cave (the first of this type of marks described in Portugal) is presented and the fossil bear remains identified and compared to a sample from NW Spain. The bears from Algar do Vale da Pena contrast with other previously known Portuguese brown bear specimens by relative small size. A new microvertebrate locality from Algarve, Santa Margarida, is presented. It is an extraordinary rich site with one fossil for every two grams of sediment selected and processed. The locality provided the first record of two arvicoline taxa in Portugal (Iberomys huescarensis and Victoriamys chalinei), which allows giving a minimal age of around 800.000 YBP for at least part of it. This makes Santa Margarida one of the oldest three localities in the Pleistocene of Portugal.
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Taru, Phillip. "Identification of mammalian species represented by fossil hairs in Parahyaena Brunnea coprolites from middle pleistocene deposits at Gladysvale Cave, South Africa." Thesis, 2013. http://hdl.handle.net/10539/12318.
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This research focuses on scale pattern and cross sectional morphology of hair to identify fossil hairs from Parahyaena brunnea (brown hyaena) coprolites, from Gladysvale cave in the Sterkfontein Valley, South Africa. The coprolites are part of a brown hyaena latrine preserved in calcified cave sediment dated to the Middle Pleistocene (257- 195 ka). Forty-eight fossil hairs were extracted from a 75 x 30 x 15 cm block using fine tweezers and a binocular microscope. They were ultrasonic cleaned in analar ethanol and examined using scanning electron microscopy. Hair identification was based on consultation of standard guides to hair identification and comparison with my own collection of samples of previously undocumented guard hairs, from 15 taxa of indigenous southern African mammals. Samples were taken from the back of pelts curated at the Johannesburg Zoo and Ditsong National Museum of Natural History in Tshwane (formerly Transvaal Museum, Pretoria).
Based on the fossil hairs identified here, this research has established that brown hyaenas shared the Sterkfontein Valley with warthog, impala, zebra, kudu and black wildebeest. These animals are associated with savanna grasslands, much like the Highveld environment of today. Fossil human hair was also noted in the coprolites. These findings provide a new source of information, on the local Middle Pleistocene fossil mammal community, and insight into the environment in which archaic and modern humans in the interior of the African subcontinent lived. Amid a scarce fossil and archaeological record for this time period, these results make a significant contribution to the ongoing debate about the role of climate change in the evolution and success of modern humans. In accordance with modern brown hyaena feeding behaviour, the presence of medium to large-sized mammal hairs in the coprolites suggests the co-existence of large feline predators in the area, or a period of active hunting, based on the behaviour of modern brown hyaenas when rearing cubs.
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Ruez, Dennis Russell 1973. "Effects of climate change on mammalian fauna composition and structure during the advent of North American continental glaciation in the Pliocene." Thesis, 2007. http://hdl.handle.net/2152/3226.
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The cooling preceding the beginning of North American continental glaciation is beautifully represented by the thick fluvial and lacustrine sequences of the Pliocene Glenns Ferry Formation at the Hagerman Fossil Beds National Monument (HAFO), Idaho. This time interval is commonly studied because it contains the elevated global temperatures predicted to result from continued anthropogenic warming. The fossil mammals at HAFO were examined to see the effects of climate change on past mammalian assemblages. The nature of the fossiliferous localities at HAFO was documented to establish which localities could be considered in situ. Additionally, the structural architecture of the beds was mapped to establish an idealized stratigraphic datum to which localities were tied. This facilitated temporal comparison of the widespread localities at HAFO. Second, a high-resolution record of climate change was created using global climate models to predict which oceanic areas varied in temperature in concert with HAFO during the middle Pliocene. Data from deep-sea cores from those oceanic areas were combined to create a proxy temperature pattern; such a detailed record from terrestrial data in the Glenns Ferry Formation is not currently possible. Selected mammalian groups, carnivorans, insectivorans, and leporids, were examined in light of the established climatic patterns. The cooling through the lower portion of the Glenns Ferry Formation corresponds to variation in the morphology of individual species, the relative abundance of species, and the species-level diversity of mammalian groups. There is a return to warm temperatures near the top of the section at HAFO, and the mammals returned to the conditions exhibited before the cool-temperature extreme. This faunal resilience, however, occurred over hundreds of thousands of years. The final paleoecologic approach established correlations between the species diversity of groups of modern mammals and modern climatic values. Many modern groups were found to be highly-significantly correlated to climate, but when the established predictive equations were applied to HAFO, the results were variable. Estimates of annual precipitation varied widely, depending on the taxonomic group, and also deviated from precipitation estimates from sedimentology. Temperature patterns were more consistent with each other and with the pattern of the deep-sea core proxy.text
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Tsukui, Kaori. "Chronology and Faunal Evolution of the Middle Eocene Bridgerian North American Land Mammal “Age”: Achieving High Precision Geochronology." Thesis, 2015. https://doi.org/10.7916/D8KS6R86.
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The age of the Bridgerian/Uintan boundary has been regarded as one of the most important outstanding problems in North American Land Mammal “Age” (NALMA) biochronology. The Bridger Basin in southwestern Wyoming preserves one of the best stratigraphic records of the faunal boundary as well as the preceding Bridgerian NALMA. In this dissertation, I first developed a chronological framework for the Eocene Bridger Formation including the age of the boundary, based on a combination of magnetostratigraphy and U-Pb ID-TIMS geochronology. Within the temporal framework, I attempted at making a regional correlation of the boundary-bearing strata within the western U.S., and also assessed the body size evolution of three representative taxa from the Bridger Basin within the context of Early Eocene Climatic Optimum. Integrating radioisotopic, magnetostratigraphic and astronomical data from the early to middle Eocene, I reviewed various calibration models for the Geological Time Scale and intercalibration of 40Ar/39Ar data among laboratories and against U-Pb data, toward the community goal of achieving a high precision and well integrated Geological Time Scale.
In Chapter 2, I present a magnetostratigraphy and U-Pb zircon geochronology of the Bridger Formation from the Bridger Basin in southwestern Wyoming. The ~560 meter composite section spans from the lower Bridger B to the Bridger E, including the Bridgerian/Uintan NALMA boundary in the uppermost part of the section. Analysis of samples from 90 sites indicates two paleomagnetic reversals that are correlated to an interval spanning Chrons C22n, C21r, and C21n by comparison to the Geomagnetic Polarity Time Scale (GPTS). This correlation places the Bridgerian/Uintan faunal boundary within Chron C21n, during the initial cooling phase following the peak of the Early Eocene Climatic Optimum. Based on the bio- and magnetostratigraphic correlation, I provide correlation of other Bridgerian/Uintan boundary-bearing sections to the GPTS, demonstrating that in the western North America, the Bridgerian/Uintan boundary occurs everywhere in Chron C21n. In addition, U-Pb zircon geochronological analyses were performed on three ash beds from the Bridger Formation. High-precision U-Pb dates were combined with the paleomagnetic polarity data of the same ash beds as well as the integrative chronostratigraphy of the basin to assess prior calibration models for the Eocene part of the GPTS. The data from the Bridger Formation indicate that the Option 3 age model of Westerhold et al. (2008) best reconciles the geochronological data from all of the ash beds except for one. Thus I favor this Option 3 model, which indicates the ages of 56.33 Ma and 66.08 Ma for the Paleocene-Eocene Thermal Maximum and Cretaceous/Paleogene boundary, respectively.
In Chapter 3, the body size evolution of three mammalian taxa from the Bridgerian NALMA was analyzed within the context of Bergmann’s Rule, which poses a correlation between the size of endotherms and climate (latitude). The Bridgerian NALMA is from a time of global cooling following the peak of the Early Eocene Climatic Optimum, thus according to Bergmann’s Rule, the Bridgerian mammals are expected to increase in size. This hypothesis is tested among Notharctus, Hyopsodus, and Orohippus, using the size of molar dentition as a proxy for their body size. These taxa represent three different ecomorphs, and I investigated if these taxa showed a pattern of body size change consistent with the prediction made by Bergmann’s Rule, and how their ecological adaptation may have affected their response to the climate change. Prior to analyzing the body size evolution, specimens of Notharctus and Hyopsodus were identified to species based on dental characters. This practice differs from previous studies in which species identification relied on relative size of the individuals and stratigraphic levels of origin. Within the new framework of morphologically determined species identification, five species of Notharctus were recognized, among which, N. pugnax, N. robustior and N. sp. indet. exhibited statistically significant body size increase in the time span of interest. Based on morphological analyses of Hyopsodus dentition, I recognized five species. Dentition-based body size analysis showed that H. lepidus and H. despiciens exhibited a statistically significant change towards larger size within the sampled interval. When analyzed at the generic level, a statistically significant increase was observed for both Notharctus and Hyopsodus. Finally, a genus-level analysis of Orohippus showed a lack of statistically significant size increase over the study interval. Thus, among the three taxa from the Bridgerian, Bergmann’s Rule is supported by Notharctus and Hyopsodus, at least at the genus level, but not by Orohippus, although the patterns are more variable at the intraspecific level.
In Chapter 4, 40Ar/39Ar dates were obtained from sanidines from the middle Eocene Henrys Fork tuff and Upper Carboniferous Fire Clay tonstein, with the goal of making highly precise measurements of these two samples, keyed to the Fish Canyon monitor standard. Analytically, both samples were well characterized, as had been shown previously. The irradiation disk was arranged such that there would have been control from the Fish Canyon surrounding each of the unknown pits. However, due to several complications in the lab during the course of the experiment, only the analyses from one run disk (Disk 677) were of the quality needed for the goals of the study. As a result, the Fish Canyon sanidine standards that were irradiated near the center of the irradiation disk had to be discarded, and thus, the neutron fluence could not be mapped out precisely across the entire disk. The 40Ar/39Ar age relative to Fish Canyon sanidines is 47.828 ± 0.205 Ma and 311.937 ± 1.282 Ma for the Henrys Fork tuff and Fire Clay tonstein, respectively (1σ, including error on the age of the monitor). Because the ages were both offset about the same amount, I explored the option of using the U-Pb ID-TIMS ages of the Henrys Fork tuff and Fire Clay tonstein to test the agreement in the chronometers. The Henrys Fork tuff was dated at 48.260 ± 0.107 Ma (1σ, including error on the age of the monitor) using the Fire Clay sanidines and assuming its age is the U-Pb zircon age. The Fire Clay tonstein was dated at 314.593 ± 0.699 Ma (1σ, including error on the age of the monitor), using the Henrys Fork sanidines and assuming its age is the U/Pb zircon age. Although the complications encountered render these data unpublishable, they show great promise as the ages of each sanidine sample, tied to the other ash using the other ash’s U-Pb age, give results that are in close agreement between the two chronometers on the same sample (e.g., 314.593 ± 0.699 Ma vs. 314.554 ± 0.020 Ma at 1σ for sanidine and zircon respectively from the Fire Clay tonstein, and 48.260 ± 0.107 Ma vs. 48.265 ± 0.008 Ma 1σ for sanidine and zircon respectively from the Henrys Fork tuff).
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OKŘINOVÁ, Isabela. "Paleoecology of fossil species of canids (Canidae, Carnivora, Mammalia)." Master's thesis, 2013. http://www.nusl.cz/ntk/nusl-166262.
Full textAbstract:
There were reconstructed phylogeny of recent and fossil species of subfamily Caninae in this study. Resulting phylogeny was used for examining possible causes of cooperative behaviour in Caninae. The study tried tu explain evolution of social behavior in canids.