Tesi: "Paleobiogeography"

1

Walls, Bradley J. "Quantitative Paleobiogeography of Maysvillian (Late Ordovician) Brachiopod Species of the Cincinnati Arch: a Test of Niche Modeling Methods for Paleobiogeographic Reconstruction." Ohio : Ohio University, 2009. http://www.ohiolink.edu/etd/view.cgi?ohiou1243010764.

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2

Frantescu, Ovidiu D. "Systematics, paleobiogeography, and paleoecology of cretaceous decapod faunas from northeast Texas." Thesis, Kent State University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3726727.

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Investigation of decapod fossils from the Pawpaw Shale, Albian, Texas, has yielded 17 new species, and seven new genera. In total, 14 brachyuran; 3 astacidean; 4 anomuran; 8 axiidean; 5 palinuridean, and one stomatopod species were described and classified according to the latest classification scheme. Shale samples from a single locality in Fort Worth were analyzed for their grain size, mineral and trace element content. The Pawpaw Shale consists of sediments derived from the Llanos uplift to the southwest of Fort Worth, and represents a fining upward sequence deposited in a restricted lagoonal environment. The decapod fauna of the Pawpaw Shale is one of the richest decapod faunas of Albian age known to date, composed of a population of adult and juvenile crabs and lobsters. The peculiar small size of the individual lobsters of this fauna is attributed to their representing an early ontogenetic stage. No trace elements known to affect the biology an physiology of extant decapods could be found in the shale samples analyzed to indicate an environmental cause for the reduced size of the Pawpaw lobsters.

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3

Frantescu, Ovidiu D. "SYSTEMATICS, PALEOBIOGEOGRAPHY, AND PALEOECOLOGY OF CRETACEOUS DECAPOD FAUNAS FROM NORTHEAST TEXAS." Kent State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=kent1368631876.

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4

Serobyan, Vahram. "Upper Devonian brachiopods and sedimentary sequences from Armenia : biodiversity, stratigraphy and paleobiogeography." Electronic Thesis or Diss., Université de Lille (2018-2021), 2021. http://www.theses.fr/2021LILUR033.

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Les séries sédimentaires carbonatées-terrigènes et les brachiopodes du Dévonien supérieur d’Arménie centrale ont été ici étudiées à partir de trois coupes distinctes (Ertych, Djravank et Noravank). Leur interprétation paléoenvironnementale a été réalisée à partir des bio- et lithofaciès afin de reconstituer leur milieux de dépôt. De plus, les coupes étudiées ont été corrélées lithostratigraphiquement, ainsi que biostratigraphiquement, en se basant sur leurs assemblages à brachiopodes. Vingt-six espèces de brachiopodes sont décrites sur la base d’un matériel récemment collecté. Quatre nouveaux genres de brachiopodes (Aramazdospirifer, Angustisulcispirifer, Pentagonospirifer et Tornatospirifer), ainsi que cinq nouvelles espèces (Crinisarina pseudoglobularis, Cyrtospirifer pseudoasiaticus, Pseudocyrtiopsis areniensis, Pentagonaspirifer abrahamyanae et Angustisulcispirifer arakelyani) sont introduits. Toutes les espèces de brachiopodes sont examinées selon des concepts taxonomiques modernes ; leurs caractéristiques internes et externes sont illustrées, à l’exception de quelques rares espèces. La variabilité morphologique intraspécifique des espèces décrites est documentée quantitativement. Le schéma biostratigraphique proposé auparavant pour l’intervalle Frasnien–Famennien du Petit Caucase (Arménie et Nakhichevan) est révisé. Plus particulièrement, la zone à Ripidiorhynchus gnishikensis–Angustisulcispirifer arakelyani, d’âge Frasnien, est proposée pour la faune trouvée dans les calcaires à péloïdes accumulés dans un cortège à haut niveau marin, alors que la zone à Aramazdospirifer orbelianus–Tornatospirifer armenicus, d’âge Fammenien inférieur, est caractérisée par des packstones/graistones de l’intervalle 4, déposés lors d’un événement transgressif. La présente étude documente également la diversité des brachiopodes signalée dans le Petit Caucase à travers l’intervalle Frasnien–Famennien inférieur et souligne un renouvellement majeur de faune parmi les rhynchonellides, les atrypides et les spiriférides. D’un point de vue paléobiogéographique, la faune étudiée a clairement des affinités avec celles connues dans d'autres régions de la marge nord-Gondwanienne, notamment celles qui s’étendent vers l’est du SAB (Bloc sud arménien) jusqu’en Afghanistan et le Pamir, bien qu’il existe également de nombreux éléments endémiques. De plus, la signification paléobiogéographique des quatre nouveaux genres est discutée, y compris de plusieurs autres espèces du Famennien qui leur sont réaffectés et qu’elles étaient connues auparavant du Nakhichevan, du Pamir (Tadjikistan), du Kazakhstan central et de la Plate-forme d’Europe de l’Est The Upper Devonian carbonate-siliciclastic sedimentary sequences and brachiopods from three distinct sections (Ertych, Djravank and Noravank) of Central Armenia are here examined. Paleoenvironmental interpretation is performed based on bio- and lithofacies to reconstruct the depositional environments in which the sedimentary sequences were accumulated. Moreover, the studied sections are correlated lithostratigraphically, as well as biostratigraphically by focusing on their brachiopod assemblages. Twenty-six brachiopod species are described on the basis of recently collected material from the Frasnian–Famennian (F–F) succession. Four new brachiopod genera (Aramazdospirifer, Angustisulcispirifer, Pentagonospirifer and Tornatospirifer) and five new species (Crinisarina pseudoglobularis, Cyrtospirifer pseudoasiaticus, Pseudocyrtiopsis areniensis, Pentagonaspirifer abrahamyanae and Angustisulcispirifer arakelyani) are introduced. All brachiopod species are examined according to modern taxonomic concepts and illustrated both externally and internally, with the exception of some rare species. The intraspecific morphological variability of the described species is documented quantitatively. The previously suggested biostratigraphic scheme for brachiopods of the F–F interval of the Lesser Caucasus (Armenia and Nakhichevan) is revised. More particularly, the Ripidiorhynchus gnishikensis–Angustisulcispirifer arakelyani brachiopod zone, of Frasnian age, characterizes the peloidal grainstones of the Interval 1 that accumulated as a highstand system tract, while the Lower Famennian Aramazdospirifer orbelianus–Tornatospirifer armenicus Zone is found in the packstones/grainstones of the Interval 4, which was deposited during a transgressive event. The present study also documents the diversity of brachiopods reported from the Frasnian–lower Famennian sequences of the Lesser Caucasus (Armenia and Nakhichevan); the synthesis of all previous and current data suggests that a major change in diversity took place amongst rhynchonellides, atrypides and spiriferides. From a paleobiogeographic viewpoint, the studied fauna clearly shares affinities with contemporaneous brachiopods known from other parts of the north-Gondwanan margin, especially from those areas that extend eastwards of the South Armenian Block (SAB) into Afghanistan and Pamir, although there are also many endemic elements. Finally, the paleobiogeographic significance of the four newly defined genera is discussed, including the re-assignment to them of several other Famennian species known previously from Nakhichevan, Pamir (Tajikistan), Central Kazakhstan and the East European Platform

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5

Samathi, Adun [Verfasser]. "Theropod dinosaurs from Thailand and Southeast Asia : phylogeny, evolution, and paleobiogeography / Adun Samathi." Bonn : Universitäts- und Landesbibliothek Bonn, 2019. http://d-nb.info/120002012X/34.

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6

Wright, David F. "Macroevolution and Paleobiogeography of Middle to Late Ordovician Brachiopods: A Phylogenetic Biogeographic Approach." Ohio University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1338324936.

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7

Gorscak, Eric. "Descriptive and Comparative Morphology of African Titanosaurian Sauropods: New Information on the Evolution of Cretaceous African Continental Faunas." Ohio University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1478778037108276.

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8

Pletka, Crystal. "Neogene Changes in Caribbean Paleoproductivity and the Diversity and Paleobiogeography of Deep-sea Benthic Foraminifera." FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/2468.

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The Neogene history of Caribbean deep-sea benthic foraminifera was investigated by calculating changes in paleoproductivity, diversity and paleobiogeography ~26 to 2 Ma, which includes the progressive closure of the Central American Seaway. Three hypotheses were tested: (1) Paleoproductivity values prior to closure of the Central American Seaway are similar in both the Caribbean and equatorial Pacific and then diverge by the time of early shoaling events; (2) Diversity values of benthic foraminifera prior to the closure of the Central American Seaway were similar in the Caribbean and EEP, and had changed by the time of early shoaling; and (3) during the Miocene and into the Pleistocene, the progressive constriction of the CAS affected deep-sea benthic foraminiferal assemblages by increasing their dissimilarity between the Caribbean and equatorial Eastern Pacific. These hypotheses were tested with 104 samples from five Caribbean and EEP deep-sea cores by calculating paleoproductivity with multiple proxies, determining diversity indices and calculating biogeographic similarity coefficients. The data supported the first two hypotheses: The greatest change in paleoproductivity occurred at ~8 Ma during seaway constriction, when values diverged between the Caribbean and EEP. After complete seaway closure at ~4 Ma, the Caribbean became oligotrophic, noted by a decrease in high-organic flux species, and an increase in Nuttalides umbonifera, an indicator species. The largest changes in species-level diversity occurred with the barrier to deep-water flow at ~12 Ma, and Caribbean diversity increased at ~8 Ma with seaway constriction. However, the third hypothesis was rejected: Increases in assemblage similarity actually occurred during most major paleoceanographic events, with the only decrease in Caribbean-EEP similarity occurring at ~12 Ma, coincident with a drop in diversity and emplacement of the Panama isthmian sill. Thus, the barrier to deep-water flow at ~12 Ma affected the composition of tropical American benthic foraminifera more than the largest change in paleoproductivity at ~8 Ma, or closure of the Central American Seaway at ~4 Ma.

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9

Chitnarin, Anisong. "Taxonomy of Permian ostracods from central northeastern, and western Thailand : implication for paleoenvironment and paleobiogeography." Paris 6, 2010. http://www.theses.fr/2010PA066123.

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Quinze coupes et deux localités de calcaires du Permien inférieur à moyen terminal appartenant au Groupe de Loei, Groupe de Saraburi et au Calcaire de Sai York (dans les régions de Loei, Petchabun, Nakhon Sawan-Lopburi et Kanchanaburi) ont été étudiées. Les calcaires qui ont été échantillonnés et traités par acétolyse à chaud, renferment de nombreux ostracodes. Ils appartiennent à 196 espèces et 41 genres. 29 espèces sont connues avec d'autres régions, 167 sont endémiques. Les assemblages d'ostracodes, comprenant des Bairdioidea, Kloedenellidae, Kirkbyidae, Hollinellidae, Paraparchitidea, Cytherideidae, Cavellinidae, Pachydomellidae, Aparchitidea, Coelonellidae et Polycopidae, sont typiquement des espèces marines peu profondes dans des environnements marins marginaux à de plate-forme externe. Les concentrations en oxygène dans l'eau, évaluées à partir des pourcentages d'ostracodes filtreurs vs détritivores, seraient approximativement de l'ordre de 5ml/l pour toutes les coupes. Vingt neuf espèces d'ostracodes sont reconnues dans d'autres régions de la Paléo-Téthys. Ces espèces sont benthiques et leurs larves ont le même mode de vie. L'indice de provincialisme suggère des relations étroites avec la Tunisie, la Chine du Sud, la Grèce, l'Oman, l'Italie, la Hongrie et Israël, en ordre décroissant. Les relations avec l'Amérique du Nord sont faibles. Les ostracodes peuvent avoir été transportés vers des régions éloignées par des courants de surfaces de l'est vers l'Ouest de la paléo-Téthys au cours du Permien. La présence d'espèces communes entre les régions de Loei, Phetchabun, et Nakhon Sawan-Lopburi suggèrent que les calcaires des groupes de Loei et de Saraburi se sont déposés dans des environnements marins peu profonds, peu éloignés les uns des autres, où les faunes d'ostracodes benthiques pouvaient se déplacer ou migrer Belonged to Loei Group, Saraburi Group, and Sai Yok Limestone (in Loei, Phetchabun, Nakhon Sawan-Lopburi, and Kanchanaburi areas) were investigated. Limestones were collected and processed by the hot acetolysis which yielded many ostracods. They are belonged to 196 species and 41 genera of which 29 species are known from other places, 167 species are endemic. The ostracod assemblages including Bairdioidea, Kloedenellidae, Kirkbyidae, Hollinellidae, Paraparchitidea, Cytherideidae, Cavellinidae, Pachydomellidae, Aparchitidea, Coelonellidae, and Polycopidae are typical shallow marine species from marginal marine to exterior platform environments. Oxygen concentration is approximately 5ml/l at all sections according to percentage of filter-feeding and deposit-feeding ostracods. Twenty-nine ostracod species known from other Permian sites within Paleotethys region are benthic inhabitants and their larvae have the same way of life. Provincialism Index suggests close relationships with Tunisia, South China, Greece, Oman, Italy, Hungary, Israel, in decreasing order. The relationships with North American species are low. The ostracods could be carried to the remote sites by surface paleocurrents from east to west in Paleotethys realms during the Permian. Presence of common species between Loei, Phetchabun, and Nakhon Sawan-Lopburi areas suggest that limestones of Loei and Saraburi Groups were deposited in shallow marine environments not far from each other where benthic ostracod fauna was able to travel or migrate

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10

Randklev, Charles R. "The Ecology and Paleobiogeography of Freshwater Mussels (Family: Unionidae) from Selected River Basins in Texas." Thesis, University of North Texas, 2011. https://digital.library.unt.edu/ark:/67531/metadc68035/.

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This dissertation has two overall objectives: first, to demonstrate the utility of paleozoological data for ongoing and future mussel-conservation efforts in Texas and second, to evaluate whether simple measures of habitat (e.g., water depth, velocity and particle size) are important for demonstrating the within-habitat spatial separation of mussels. Although these topics may seem disparate, both are important for increasing our understanding of unionid ecology and biogeography. Chapters 1 through 3 examine the use of paleozoological data for mussel conservation. Although these types of data are not new they have rarely been used in mussel conservation efforts within Texas. This is unfortunate because paleozoological data can provide an excellent record of the mussel fauna prior to wide-scale modern impacts and in areas where historical survey data are lacking. Chapter 4 examines whether assessments of microhabitat for mussels using simple measures of habitat (e.g., water velocity, depth and particle size) are useful. Recent studies have suggested that these measures do not explain the mussel distribution in flowing streams. If this is correct, instream flow studies using this approach need to be revised. Results of Chapter 4 indicate that mussels in the lower Brazos River basin are constrained in distribution by the availability of heterogenous substrate. Appendix A, details the first account of a living population of Truncilla macrodon, which is a candidate species for the Endangered Species Act (ESA). The population was found while conducting mussel instream flow studies in the lower Brazos River basin.

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Huber, Brian Thomas. "Upper Campanian-Maastrichtian foraminifers of the high southern latitudes : ontogenetic morphometric systematics, biostratigraphy, and paleobiogeography /." The Ohio State University, 1988. http://rave.ohiolink.edu/etdc/view?acc_num=osu148759680782189.

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12

Byun, S. Ashley. "Quaternary biogeography of western North America insights from mtDNA phylogeography of endemic vertebrates from Haida Gwaii /." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ37334.pdf.

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13

Dudei, Nicole L. "The impact of the Richmondian Invasion on paleobiogeographic distribution of taxa in the Late Ordovician C₄ sequence (Richmondian Stage, Cincinnati, Ohio) including a comparison of range reconstruction methods." Ohio : Ohio University, 2009. http://www.ohiolink.edu/etd/view.cgi?ohiou1245437297.

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14

Maguire, Kaitlin Clare. "Paleobiogeography of Miocene to Pliocene Equinae of North America a phylogenetic biogeographic and niche modeling approach /." Ohio : Ohio University, 2008. http://www.ohiolink.edu/etd/view.cgi?ohiou1212778747.

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15

Olivier, Chloé. "Phylogeny, paleobiogeography, and paleophysiology of the Triassic dicynodonts (Therapsida, Anomodontia) : contributions of the Laotian and Moroccan forms." Electronic Thesis or Diss., Sorbonne université, 2020. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2020SORUS399.pdf.

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Les dicynodontes sont emblématiques de la période du Permien-Trias (P-Tr), du fait de leur survie à la grande crise P-Tr. Cependant, les conditions de leur résilience et leur évolution au cours du Trias restent peu connues. Ce travail s'est concentré sur les formes laotiennes et marocaines. La résilience des dicynodontes apparait plus précoce, de par l’ajout de deux nouvelles espèces laotiennes (Counillonia superoculis et Repelinosaurus robustus) datée du Trias inférieur. Malgré leurs relations phylogénétiques non consensuelles, elles confirment la survie de plusieurs lignées de dicynodontes à la crise. Les modèles paléophysiologiques ont conclu à une endothermie chez tous les dicynodontes permiens et triasiques étudiés, réfutant l’hypothèse d’un métabolisme élevé pour expliquer un différentiel de survie. Ils ont également montré une acquisition unique de l'endothermie mammalienne au moins au Permien moyen, chez les Neotherapsida. Du fait de l'âge et du mode de vie terrestre des dicynodontes, une connexion terrestre entre le bloc indochinois et la Pangée a donc été supposée au moins dès la fin Permien-début Trias. Du matériel post-crânien marocain inédit de dicynodonte a été étudié et une révision taxonomique des formes marocaines a été effectuée. Moghreberia nmachouensis a été considérée valide et distincte du genre Placerias. L’étude du matériel crânien d'Azarifeneria n'a pas permis de le distinguer des autres genres triasiques. Outre Moghreberia, un second morphotype plus robuste a été remarqué dans le matériel postcrânien. La grande taille de Moghreberia et de ce deuxième morphotype ont confirmé une augmentation de la taille corporelle des dicynodontes au cours du Trias Dicynodonts represent an emblematic Permian-Triassic (P-Tr) taxa to survive the big crisis at the end of Permian. The evolution of Triassic dicynodonts and their recovery conditions are still unclear. This work focused on the Laotian and Moroccan forms. The post-crisis recovery of dicynodonts would appear to be earlier as supported by the description of two new Laotian species (Counillonia superoculis and Repelinosaurus robustus) in Early Triassic. Despite their non-consensual phylogenetic relationships, they support the survivorship of multiple lineages across the P-Tr boundary. Paleophysiological models inferred high metabolism in Permian and Triassic studied dicynodonts, refuting the hypothesis of a high metabolism to mainly explain differential survival beyond the crisis. They also highlighted a unique acquisition of the endothermy in Synapsida occurring at least in middle Permian at the Neotherapsida node. Considering the age and the terrestrial lifestyle of dicynodonts, a terrestrial connection between the Indochina Block and Pangea could thus be interpreted at least in late Permian-Early Triassic. A new dicynodont postcranial material discovered in Morocco was studied and a taxonomic revision of the Moroccan forms was made. Moghreberia nmachouensis was considered as valid and clearly distinguished from Placerias. The restudy of the cranial material of Azarifeneria did not allow distinguishing it from other Triassic genera. In addition to Moghreberia, a second morphotype, more robust, could be noticed in the postcranial material. The large size of Moghreberia and of the second big morphotype confirmed an increase of the body size in dicynodonts during the Triassic

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Swisher, Robert E. "Paleobiogeographical and Evolutionary Analysis of Late Ordovician, C5 Sequence Brachiopod Species, with Special Reference to Rhynchonellid Taxa." Ohio University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1245445583.

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17

Swisher, Robert E. "Paleobiogeographical and evolutionary analysis of Late Ordovician, C₅ sequence brachiopod species, with special reference to Rhynchonellid taxa." Ohio : Ohio University, 2009. http://www.ohiolink.edu/etd/view.cgi?ohiou1245445583.

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18

Quaglio, Fernanda. "Taxonomia de invertebrados fósseis (Oligoceno-Mioceno) da ilha Rei George (Antártica ocidental) e paleobiogeografia dos Bivalvia cenozóicos da Antártica." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/44/44139/tde-25042008-153222/.

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As pesquisas apresentadas nesta dissertação integram o projeto CNPq - PROANTAR 550352/02-3 \"Mudanças paleoclimáticas na Antártica durante o Cenozóico: o registro geológico terrestre\", que estuda os depósitos cenozóicos da ilha Rei George em busca elucidação do histórico ambiental e climático desta região antártica. A evolução dos padrões de circulação marinha e atmosférica no Hemisfério Sul ocorreu em resposta ao isolamento geográfico e térmico da Antártica, resultado de sua separação da Austrália, no limite Eoceno/Oligoceno, e da América do Sul, no final do Oligoceno. Sob este aspecto, o estudo de organismos fósseis registrados nos depósitos cenozóicos da Antártica contribui para o entendimento das evoluções biológicas e ambientais ocorridas concomitantemente às mudanças paleogeográficas, oceanográficas e climáticas na região ao longo do Cenozóico. Frente à dificuldade de acesso, demanda logística e extensa cobertura de gelo, apenas uma pequena porção do registro geológico da Antártica está acessível para pesquisa. Afloramentos da ilha Rei George registram as mudanças climáticas e ambientais ocorridas do Oligoceno ao Mioceno, incluindo evidências do primeiro evento de glaciação perene no oeste do continente (Oligoceno). A despeito da abundância de fósseis nos estratos cenozóicos da ilha, são poucos os trabalhos taxonômicos com descrição sistemática detalhada de bivalves fósseis. O primeiro módulo do presente estudo apresenta a descrição taxonômica de invertebrados de depósitos cenozóicos aflorantes em duas localidades da ilha Rei George, Antártica ocidental. Da Formação Cape Melville (Mioceno), península Melville, foram descritos sete táxons de bivalves, incluindo seis espécies novas. Da Formação Polonez Cove (Oligoceno), Pico Vauréal, uma região previamente inexplorada paleontologicamente, foram descritos sete táxons de invertebrados (bivalves, braquiópodes, tubos de serpulídeos, briozoários e fragmentos de equinodermes), incluindo duas espécies novas. O segundo módulo corresponde à reunião dos gêneros de bivalves registrados em depósitos cenozóicos da Antártica. A análise do registro apontou para o conhecimento bastante incipiente sobre a diversidade de bivalves antárticos ao longo do Cenozóico. Além disso, a comparação entre gêneros de bivalves cenozóicos registrados na Antártica e Nova Zelândia revelou que a maior parte dos gêneros compartilhados está registrada em depósitos eocênicos, o que suporta o isolamento geográfico da Antártica e a redução do intercâmbio faunístico entre a Antártica e regiões periféricas após o Oligoceno. A análise do registro sugeriu um evento de dispersão intenso durante o Eoceno, e pequenos pulsos de dispersão após o Oligoceno. O padrão de distribuição dos táxons concorda parcialmente com as reconstituições de paleocorrentes disponíveis na literatura. A dispersão durante o Eoceno teria ocorrido da Antártica para a Nova Zelândia na direção do Atlântico para o Pacífico. Este evento de dispersão concorda com a hipótese de existência de conexões marinhas de plataforma rasa entre o oeste e o leste da Antártica (\"Passagem de Shackleton\") e da província Weddeliana do final do Cretáceo ao Eoceno. Os eventos de dispersão pósoligocênicos teriam ocorrido durante e após o estabelecimento da Corrente Circum-Antártica, não mais pela \"Passagem de Shackleton\", mas margeando a Antártica pelas bordas ocidental atlântica e oriental em direção à Nova Zelândia. A análise do registro dos bivalves cenozóicos da Antártica também concorda com a hipótese de glaciação perene a partir do início do Oligoceno na região leste do continente, e na metade do Oligoceno na região oeste, com temperaturas mais amenas que as observadas atualmente. The research presented in this dissertation comprised part of the CNPq - PROANTAR Project 550352/02-3 \"Mudanças paleoclimáticas na Antártica durante o Cenozóico: o registro geológico terrestre\", which studies Cenozoic deposits from King George Island in order to elucidate the environmental and climatic Cenozoic histories of this Antarctic region. Cenozoic evolution of marine and atmospheric circulation in the Southern Hemisphere occurred in response to the geographic and thermal isolation of Antarctica, which resulted from the separation of Antarctica from Australia, around Eocene/Oligocene boundary, and from South America, during the late Oligocene. Thus, study of fossil organisms from Antarctic Cenozoic deposits contributes to the understanding of biological and environmental evolutions that accompanied paleogeographic, oceanographic and climatic changes during the Cenozoic. As a result of the difficult access, logistic demand and extensive ice cover, only a small part of the Cenozoic Antarctic record is available for study. King George Island records climatic and environmental changes from the Oligocene to the Miocene, including evidence of the first full-scale glaciation (Oligocene) of West Antarctica. Despite the abundance of fossils in Cenozoic deposits of the island, taxonomic studies with detailed systematic descriptions of bivalves are very rare. The first section of this work consists of taxonomic descriptions of invertebrates from Cenozoic deposits cropping out in two localities of King George Island, West Antarctica. Seven taxa of bivalves, including six new species were described from the Cape Melville Formation (Miocene), at Melville Peninsula. Seven taxa of invertebrates (bivalves, brachiopods, serpulid tubes, bryozoans, and echinoderm fragments) were described from the Polonez Cove Formation (Oligocene), at Vauréal Peak, a site previously unexplored paleontologically. The second section presents the results of a survey of the Cenozoic fossil record of Antarctic bivalves. The analysis of the fossil record confirmed that the current knowledge about the Cenozoic diversity of the group is very scarce. Moreover, comparison of Cenozoic bivalve genera from Antarctica and New Zealand showed that the greatest number of shared taxa is recorded in Eocene deposits. This finding supports the geographic isolation of Antarctic and the drop in faunal interchange between Antarctica and periphery after the Oligocene. Analysis of the fossil record suggested an intensive dispersal event during the Eocene, and restricted pulses of dispersal from the Oligocene onwards. The distribution pattern of taxa provides partial support for available reconstructions of marine currents. Eocene dispersal would have occurred from Antarctica to New Zealand in Atlantic-Pacific direction. This dispersal event is consistent with the hypothesis of shallow marine connections between West and East Antarctica (\"Shackleton Seaway\"), as well of the existence of the Weddellian Province from the Late Cretaceous to the Eocene. Dispersal events following the Oligocene would have occurred during and after the establishment of the Circum-Antarctic Current, along the West-Atlantic and East margins of Antarctica towards New Zealand, and no longer through \"Shackleton Seaway\". These analyses also support the hypothesis of full-scale glaciation in West Antarctica from the early Oligocene onwards, and in East Antarctica since the mid-Oligocene, with warmer temperatures than today.

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Garvey, Samuel T. "A new high-latitude Tylosaurus (Squamata, Mosasauridae) from Canada with unique dentition." University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1584001060097071.

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20

Ferreira, Gabriel de Souza. "Evolução e filogenia de Pleurodira (Testudines) com a descrição de uma nova espécie de Bairdemys (Podocnemidae) do Mioceno médio da Venezuela." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/59/59139/tde-21032016-165532/.

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Apesar de negligenciados por muito tempo, os Pleurodira, uma das duas linhagens de Testudines (cágados, jabutis e tartarugas-marinhas), vem atraindo crescente atenção dos pesquisadores, com trabalhos que geralmente tratam da descrição de novas espécies (viventes ou extintas), de comportamentos ou hábitos alimentares, ou de análises filogenéticas dos sub-grupos de Pleurodira, como Chelidae ou Pelomedusoides, esta sub-dividida em duas linhagens com representates viventes: Pelomedusidae e Podocnemidae. Análises filogenéticas com táxons terminais de todos os principais grupos de Pleurodira existem apenas com dados moleculares. Assim, uma análise baseada em dados morfológicos que englobe táxons de todos os grandes clados do grupo, incluindo fósseis, faz-se necessária para melhor compreensão da história evolutiva do grupo. Nesta dissertação, descrevemos uma nova espécie de Bairdemys (Podocnemidae) do Mioceno médio da Venezuela e a incluímos em uma análise filogenética com ampla amostragem taxonômica, incluindo táxons de todas as linhagens de Pleurodira. Esta análise é baseada em caracteres morfológicos (novos ou previamente propostos) e a maior análise filogenética exclusiva do grupo já realizada, permitindo inferências sobre padrões gerais de diversificação e morfologia de Pleurodira. Ao mesmo tempo, o novo táxon descrito apresenta características morfológicas que, juntamente com aspectos geológicos de sua localidade tipo, permitem a inferência de que houve, durante o Cenozóico, uma irradiação marinha de Podocnemidae, que alcançou grande sucesso, principalmente no final do Oligoceno e começo do Mioceno Though neglected for a long time, one of the two lineages of Testudines (turtles and tortoises) the Pleurodira has been attracting the researchers, whose articles usually deal with descriptions of new species (extant and extinct), behavior or feeding habits, or phylogenetic analyzes of one of the subgroups of Pleurodira, Chelidae or Pelomedusoides, the latter subdivided in two lineages with extant taxa: Pelomedusidae and Podocnemidae. There some phylogenetic analyzes with terminal taxa from the main groups of Pleurodira, but only with molecular data. Therefore, a morphological data analysis containing taxa from all the clades of this group, including fossils, is necessary to better understand the evolutionary history of this lineage. In this dissertation, I describe a new species of Bairdemys (Podocnemidae) from the middle Miocene of Venezuela, and I include it in a phylogenetic analysis with extensive taxonomic sampling, including taxa from all the lineages of Pleurodira. This analysis is based on morphological characters (new and previously proposed ones) and it is the largest exclusive phylogenetic analysis ever made for Pleurodira, allowing inferences about the general patterns of diversification and morphology of the group. At the same time, the new described táxon shows morphological characters that, along with geological aspects of its type locality, allow inferences about a marine wave of diversification of Podocnemidae during the Cenozoic, which achieved great success, specially by the end of Oligocene and beginning of Miocene

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Ferreira-Oliveira, Luis Gustavo [UNESP]. "Conchostráceos permianos da bacia do Paraná: taxonomia, evolução, bioestratigrafia e paleobiogeografia." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/102996.

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Made available in DSpace on 2014-06-11T19:32:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-08-31Bitstream added on 2014-06-13T19:42:53Z : No. of bitstreams: 1 oliveira_lgf_dr_rcla.pdf: 2551069 bytes, checksum: acd81b14b612f8d3d79d2b7529438352 (MD5) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) O trabalho apresenta uma revisão dos conchostráceos da Formação Rio do Rasto (Bacia do Paraná, Permiano) e discussões substanciadas, em parte, pelos resultados dos experimentos realizados com representantes viventes cultivados em aquários. Concluiu-se que diversas características das carapaças normalmente usadas para a classificação dos conchostráceos fósseis não são diagnósticas para a distinção de táxons porque variam de acordo com fatores tafonômicos, ecológicos e ontogenéticos. Os conchostráceos vivem em águas continentais, são extremamente esteno-halinos e, ao contrário de alguns paradigmas da literatura, não vivem obrigatoriamente em corpos d'água efêmeros, toleram a presença de peixes predadores em seu habitat e duas espécies do mesmo gênero num único corpo d'água. Tais observações coadunam com o registro litológico e paleontológico da parte inferior da Formação Rio do Rasto, depositada em condições lacustres. A parte superior, onde há mais fácies eólicas e evidências de aumento de aridez, apresenta diversidade maior de conchostráceos, incluindo Hemicycloleaia mitchelli, uma espécie que permite realizar correlações cronoestratigráficos com a Austrália e Rússia. Sua idade provavelmente é neotatariana (=wuchiapingiana). Outros táxons, como Monoleiolophus unicostatus, também foram considerados nas correlações, estimando-se que a Formação Rio do Rasto esteja compreendida no Permiano médio-superior. Conchostracans of the Rio do Rasto Formation (Paraná Basin, Permian) are revised and discussions based on experiments with living conchostracans are presented. One conclusion is that many carapace characteristics frequently used for classification change according to taphonomic, ecologic and ontogenetic factors. The conchostracans live in continental fresh waters and, on the contrary of some paradigms of the literature, the organisms are not restricted to ephemeral water bodies and tolerate the presence of predatory fishes and two species of one single genus. These observations combine well with the lithological and paleontological record of the lower Rio do Rasto Formation deposited under lacustrine conditions. The upper part, formed under more arid conditions, presents bigger conchostracan diversity and includes Hemicycloleaia mitchelli. This species may be used for wide correlations with Australia and Russia, and its age probably is Late Tatarian (= Wuchiapingian). Other taxa, as Monoleiolophus unicostatus, were also used for correlations and the age of the formation may be interpreted as mid to late Permian.

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Dudei, Nicole L. "The Impact of the Richmondian Invasion on Paleobiogeographic Distribution of Taxa in the Late Ordovician C4 Sequence (Richmondian Stage, Cincinnati, Ohio) Including a Comparison of Range Reconstruction Methods." Ohio University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1245437297.

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Censullo, Shaolin Meliora. "Did Alternating Dispersal and Vicariance Contribute to Increased Biodiversification During the Great Ordovician Biodiversification Event?: A Phylogenetic Test Using Brachiopods." Ohio University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1586947231228706.

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24

Shafer, David Scott. "The timing of late Quaternary monsoon precipitation maxima in the southwest United States." Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184766.

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The southwest monsoon is responsible for a summer precipitation maximum for much of the southwest U.S. Biostratigraphies of pollen, plant macrofossils, and aquatic fossils in lakes from near modern monsoon boundaries in conjunction with climate modelling suggests variations in strength of the monsoon system during the late Quaternary. At Montezuma Well, Arizona, high percentages of Pinus and Juniperus pollen as well as maximum influxes of Quercus and Gramineae pollen suggest a shift from dominantly winter to summer precipitation between ca. 12,000 and 9000 yr BP. Maximum aridity occurred 7000-4000 yr BP, coincident with lowest lake levels. In the High Plateaus region of the Colorado Plateau, high Artemisia to Chenopodiaceae-Amaranthus pollen ratios suggests precipitation maxima until ca. 6000 yr BP at Fryingpan Lake and 5000 yr BP at Posy Lake. Pollen records suggest that Pinus edulis, P. ponderosa, and Quercus gambelii, were present on the western Colorado Plateau throughout the Holocene. Expansion of shadscale steppe vegetation at low elevations and upslope movement of ecotones for Pinus edulis, P. ponderosa, and Q. gambelii after ca. 6000 yr BP and low lake levels ca. 5000-3700 yr BP, suggest a period of maximum aridity from decreased summer precipitation. In the San Luis Valley, Colorado, pollen records from Head Lake on the basin floor suggest an expansion of oaks and junipers at the Pleistocene/Holocene boundary that may indicate increased summer precipitation. Lake levels of Head Lake fell sharply after ca. 9500 yr BP. Pollen records from Como Lake in the Sangre de Cristo Mountains suggest that Pinus ponderosa was established in the area by ca. 12,000 yr BP and Pinus edulis by ca. 9500 yr BP. Highland regions such as the High Plateaus (until ca. 6000-5000 yr BP) and central Colorado (until ca. 4000 yr BP) may have experienced Holocene summer precipitation maxima later into the Holocene than sites in lower elevation regions. Regional orographic uplift as a catalyst for convective summer precipitation may be responsible for the duration of summer precipitation maxima in these regions. On a longitudinal gradient, sites to the west such as in the southern Great Basin and Mohave Desert may have recorded enhanced summer precipitation earlier, reflecting different histories of the low-level jets in the southwest. The paleoecologic record generally confirm predictions of general circulation models (GCMs) that southwest monsoon circulation was enhanced from 12,000-6000 yr BP in response to peaks in annual (11,500-11,000 yr BP) and summer insolation (10,000-9000 yr BP) during the late Quaternary.

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25

Mtimet, Moncef Said. "The microvertebrates (Micrommamals, Amphibians, Reptiles, Aves and Fishes) from the archeopaleontological site of Wadi Sarrat (NW Tunisia) Bio-geo-chronology, Paleobiogeography and Paleoenvironmental reconstruction." Doctoral thesis, Universitat Rovira i Virgili, 2021. http://hdl.handle.net/10803/673158.

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L’estudi dels microvertebrats del jaciment d’Oued Sarrat, situat al nord-oest de Tunísia, ens va permetre identificar 24 espècies compostes per 9 rosegadors (Mus aff. spretus, M. cf. hamidae, Paraethomys rbiae, Praomys sp., Meriones sp ., Dipodillus (Gerbillus) compestris, Eliomys sp., Arvicanthis sp. I, Dendromus sp.), 3 espècies d’anurs (Discoglossus pictus, Bufo mauritanicus i Pelophylax saharicus), 1 queloni (Emys sp./Mauremys sp.), 8 escamats [2 sargantanes (Eumeces sp., Lacertidae indet. Small size), 2 morfotips de colubrids (Macroprotodon sp. i Hemorrhois sp.), 1 espècie de Colubridae s.l. (Coronella sp./Telescopus sp.), 2 Natricidae (Natrix natrix i N. maura), un viperidae (Macrovipera / Daboia sp.)], 1 espècie d'Erycinea (Boidae), 1 espècie de peix d'aigua dolça de la família dels Cyprinidae i una petita au pertanyent a la família de les Passeriformes. La biocronologia de la sèrie Oued Sarrat es va dur a terme a partir de la distribució vertical d’espècies de microvertebrats, així com de l’associació de tota la fauna recollida. La espècie índex Paraethomys rbiae té una ocurrència que no supera el límit del Pleistocè inferior-Pleistocè mitjà en tots els jaciments del nord d’Àfrica, i indica que el lloc està datat a la base del Pleistocè mitjà, 700 ka, corresponent a la base del chron normal Brunhes. L’estudi paleomagnètic realitzat en mostres del jaciment va revelar que la polaritat és normal. El estudio de los microvertebrados del yacimiento de Oued Sarrat, situado en el noroeste de Túnez, nos permitió identificar 24 especies compuestas por 9 roedores (Mus aff. spretus, M. cf. hamidae, Paraethomys rbiae, Praomys sp., Meriones sp., Dipodillus (Gerbillus) compestris, Eliomys sp., Arvicanthis sp., y Dendromus sp.), 3 especies de anuros (Discoglossus pictus, Bufo mauritanicus y Pelophylax saharicus), 1 quelonio (Emys sp./Mauremys sp.), 8 escamados [2 lagartijas (Eumeces sp., Lacertidae indet. Small size), 2 morfotipos de colúbridos Macroprotodon sp. y Hemorrhois sp.), 1 especie de Colubridae S.L. (Coronella sp./Telescopus sp.), 2 Natricidae (Natrix natrix y N. maura), un Viperidae (Macrovipera / Dabo sp.)], 1 especie de Erycinea (Boidae), 1 especie de pez de agua dulce de la familia Cyprinidae y una pequeña ave perteneciente a la familia de las Passeriformes. La biocronología de la serie Oued Sarrat se llevó a cabo a partir de la distribución vertical de especies de microvertebrados, así como de la asociación de toda la fauna recogida. La especie índice Paraethomys rbiae tiene una ocurrencia que no supera el límite del Pleistoceno inferior-Pleistoceno medio en todos los yacimientos del norte de África, e indica que el lugar está datado en la base del Pleistoceno medio, 700 ka, correspondiente a la base del Chron normal Brunhes. El estudio paleomagnético realizado en muestras del yacimiento reveló que la polaridad es normal. The study of the microvertebrates from Oued Sarrat site, located in the north-west of Tunisia, allowed us to identify 24 species composed by 9 rodents (Mus aff. spretus, M. cf. hamidae, Paraethomys rbiae, Praomys sp., Meriones sp., Dipodillus (Gerbillus) compestris, Eliomys sp., Arvicanthis sp. and Dendromus sp.), 3 species of anurans (Discoglossus pictus, Bufo mauritanicus and Pelophylax saharicus), 1 chelonian (Emys sp./Mauremys sp.), 8 squamates [2 lezards (Eumeces sp., Lacertidae indet. Small size), 2 morphotypes of colubrids (Macroprotodon sp. and Hemorrhois sp.), 1 species of Colubridae s.l. (Coronella sp./Telescopus sp.), 2 Natricidae (Natrix natrix and N. maura), 1 viperidae (Macrovipera / Daboia sp.)], 1 species of Erycinea (Boidae), 1 species of freshwater fish of the Cyprinidae family and 1 small bird belonging to the Passeriformes family. The biochronology of the Oued Sarrat series was carried out from the vertical distribution of species of microvertebrates as well as the association of all the collected fauna. The species index Paraethomys rbiae has an occurrence not exceeding the Lower Pleistocene-Middle Pleistocene limit in all North African sites indicates that the site is dated to the beginning of the Middle Pleistocene, about 700 ky, corresponding to the base of the normal chron Brunhes. A paleomagnetic study carried out on samples from the site revealed that the polarity is normal.

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Gunnin, R. Davis, Blaine W. Schubert, Joshua X. Samuels, and Keila E. Bredehoeft. "A new genus of desmognathan salamander (Plethodontidae) from the early Pliocene Gray Fossil Site of Northeast Tennessee." Digital Commons @ East Tennessee State University, 2019. https://dc.etsu.edu/asrf/2019/schedule/65.

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Many organisms are known to reach high levels of endemism and biodiversity in the temperate forests of Southern Appalachia, especially in the dense forests and rugged terrain of the Blue Ridge physiographic province. Many plants and fungi reach their highest levels of biodiversity in these mountains, as does one group of vertebrates: the lungless salamanders, Plethodontidae. This family of salamanders hosts the most species of any other group of salamanders on earth and has adapted to a wide range of habitats. Only two of the approximately twenty-seven known genera are not found in North or South America, and while we know much about the modern-day biology of this family, few fossils older than ~15,000 years have been recovered, complicating our understanding of the historical distribution of this group and the timing of key evolutionary events within the family. Recently discovered salamander fossils from the Gray Fossil Site provide the foundation of this project. We describe these exceptionally large plethodontid remains to a new genus that belongs to the group containing dusky salamanders, or desmognathans. The morphology of the fossil material resembles Phaeognathus hubrichti, an extant burrowing species from southern Alabama with a suite of primitive characteristics. Comparison of the fossil material to modern desmognathans using geometric statistical methods has revealed that the extinct form was likely similar in lifestyle to P. hubrichti, but considerably larger. It was unparalleled in the southern Appalachians in terms of size and ecology, and reveals a more complex evolutionary history for desmognathan salamanders.

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MacKenzie, Richard Allen III. "Exploring Late Cretaceous Western Interior Ammonoid Geographic Range and Its Relationship to Diversity Dynamics Using Geographic Information Systems (GIS)." Bowling Green State University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1194232321.

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Devillez, Julien. "Les Erymida (Crustacea, Decapoda) : un groupe éteint ?" Thesis, Paris, Muséum national d'histoire naturelle, 2018. http://www.theses.fr/2018MNHN0022/document.

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Les érymides sont des crustacés décapodes marins ayant une morphologie comparable à celle des homards actuels. Ils sont regroupés au sein d’une unique famille, les Erymidae Van Straelen, 1925, caractérisée par la présence d’une plaque intercalaire dorsale. Ces crustacés sont présents dès la fin du Permien. Ils se sont diversifiés et répandus dans le monde entier au Jurassique et ont perduré jusqu’au Paléocène. Ils sont particulièrement abondants au Jurassique, fossilisés dans des dépôts issus d’environnements variés : de faible profondeur – comme les calcaires lithographiques de Solnhofen (Allemagne) –, très profonds – comme La Voulte (France) –, ou encore dans différents milieux de plate-forme – comme le Terrain à Chailles (France). Depuis les premières descriptions d’érymides, au début du XIXe siècle, de nombreux auteurs se sont attachés à décrire de nouvelles formes et à tenter d’élucider les affinités phylogénétiques de ces crustacés éteints. Ces nombreux travaux ont abouti à l’installation et à la propagation de confusions rendant douteuse la systématique des érymides tant au niveau des genres que des espèces. Ces problèmes taxinomiques particulièrement marqués chez les érymides — on parle d’ailleurs de « problème érymidien » — sont accompagnés d’un débat sur leur classification au sein des Pleocyemata. Jusqu’au début du XXIe siècle, la majorité des auteurs les classaient dans l’infraordre des Astacidea mais de récentes analyses phylogénétiques suggèrent l’intégration des érymides au sein des Glypheidea. Une autre étude a même abouti à la remise en cause du statut éteint des érymides. En effet, Schram & Dixon (2004) ont observé la plaque intercalaire sur l’actuel Enoplometopus A. Milne Edwards, 1862. Leur analyse a ensuite conduit au regroupement de cette forme actuelle avec les érymides au sein d’un même clade nommé Erymida. Les objectifs de cette thèse sont donc de remédier aux problèmes taxinomiques des érymides, d’élucider leurs affinités phylogénétiques et d’apporter des éléments permettant de mieux comprendre leur mode de vie et leur succès évolutif. Pour ce faire, une révision systématique aussi exhaustive que possible, appuyée sur l’étude de plus d’un millier de spécimens, a été réalisée. Elle a permis d’homogénéiser la description des 6 genres et des 75 espèces reconnues et d’identifier les caractères nécessaires à l’étude phylogénétique. L’arbre obtenu montre clairement que les érymides constituent un groupe particulier d’Astacidea auquel Enoplometopus n’appartient pas. De plus, la topologie de l’arbre de strict consensus soutient une refondation complète de la systématique du groupe. D’une unique famille, les érymides se retrouvent désormais répartis dans deux familles, distinguées par la présence/absence de la zone post-orbitaire : les Enoploclytidae n. fam. et les Erymidae. Cette dernière est d’ailleurs elle-même divisée en sous-familles, Eryminae Van Straelen, 1925 et Tethysastacinae n. s.–fam., en raison de l’architecture très simple des sillons de la carapace de Tethysastacus Devillez et al., 2016 comparée à celle des autres genres. Cette étude a aussi été l’occasion de formuler des hypothèses paléobiogéographiques qui demeurent, hélas, en grande partie spéculatives et incomplètes du fait des importantes discontinuités géographiques et stratigraphiques du registre fossile. Les observations de stades larvaires, des yeux, de la morphologie des pinces, de pores cuticulaires et de la variabilité intraspécifique chez certains spécimens ont également permis, en s’appuyant sur les formes actuelles, d’émettre des hypothèses sur le mode de vie de ces crustacés disparus. Enfin, la grande tolérance environnementale déduite des différentes formations géologiques ayant livré des érymides fossiles est probablement une des clés de leur succès au Mésozoïque et soulève la question des raisons de leur extinction Erymids are marine decapod crustaceans with a morphology close to that of extant lobsters. They are grouped within an unique family, Erymidae Van Straelen, 1925, based on the presence of a characteristic intercalated plate. These crustaceans were already present in the Permian, have become diversified and widespread during the Jurassic and have lasted until the Paleocene. The erymids are abundant during the Jurassic. They fossilized in deposits from various paleoenvironments: shallow water environments – like lithographic limestones from Solnhofen (Germany) –, from deep environments – like in La Voulte (France) –, and also from different platform environments – like the Terrain à Chailles (France). Since the first descriptions of erymids in the first part of the XIXth century, numerous authors have described new species and have attempted to establish the phylogenetic affinities of these extinct crustaceans. This high number of studies resulted with the apparition and propagation of confusions. So, the systematics of the erymids has become doubtful at both generic and specific levels. These taxonomic problems strongly affecting the erymids — the so called « erymidian problem » — are increased by their uncertain phylogenetic relationships among the Pleocyemata. Until the XXIst century, most of the authors classified the erymids within the infraorder Astacidea but recent phylogenetic analyses suggest an integration within Glypheidea. Moreover, a study has led to question the extinct status of the erymids. Indeed, Schram & Dixon (2004) have observed an intercalated plate in the extant Enoplometopus A. Milne Edwards, 1862. Their analysis has resulted with the clustering of this extant lobster together with the erymids within a same clade named Erymida. So, the purposes of this thesis are to rectify the taxonomic problems of the erymids, to elucidate their phylogenetic affinities and to provide observations which enable a better comprehension of their lifestyles and their evolutionary success. To reach these goals, a systematic review, supported by the examination of more than a thousand specimens, has been done. It has resulted in a homogenisation of the descriptions of the 6 genera and 75 species herein recognized and in the identification of useful characters for the phylogenetic study. The phylogenetic tree obtained clearly shows that erymids form a particular group of Astacidea and that Enoplometopus does not belong to this group. Moreover, the topology of the strict consensus tree supports a new systematic building of the group. From a unique family, the erymids are now spread into two families supported by the absence/presence of a post-orbital area: Enoploclytidae n. fam. and Erymidae. The last is also divided in subfamilies, Eryminae Van Straelen, 1925 and Tethysastacinae n. s.-fam., based on the very simple carapace groove pattern of Tethysastacus Devillez et al., 2016. This new study on the erymids was also an occasion to provide some paleobiogeographic hypotheses. But, unfortunately, they remain speculative and incomplete due to geographic and stratigraphic discontinuities of the fossil record. Observations of larval stages, of eyes, of P1 chela morphologies, of cuticular pores, and of intraspecific variability on some specimens have also enabled comparisons with extant forms. These observations led to provide hypotheses on the lifestyle of these extinct lobsters. Finally, the strong environmental tolerance was probably one of the keys of the success of the erymids during the Mesozoic but raised interrogations about the reasons of their extinction

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Ferreira-Oliveira, Luis Gustavo. "Conchostráceos permianos da bacia do Paraná : taxonomia, evolução, bioestratigrafia e paleobiogeografia /." Rio Claro : [s.n.], 2007. http://hdl.handle.net/11449/102996.

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Orientador: Rosemarie Rohn Davies Banca: Ana Luisa Brossi Garcia Banca: Fresia Soledad Ricardi Torres Branco Banca: Oscar Rösler Banca: Thomas Rich Fairchild Resumo: O trabalho apresenta uma revisão dos conchostráceos da Formação Rio do Rasto (Bacia do Paraná, Permiano) e discussões substanciadas, em parte, pelos resultados dos experimentos realizados com representantes viventes cultivados em aquários. Concluiu-se que diversas características das carapaças normalmente usadas para a classificação dos conchostráceos fósseis não são diagnósticas para a distinção de táxons porque variam de acordo com fatores tafonômicos, ecológicos e ontogenéticos. Os conchostráceos vivem em águas continentais, são extremamente esteno-halinos e, ao contrário de alguns paradigmas da literatura, não vivem obrigatoriamente em corpos d'água efêmeros, toleram a presença de peixes predadores em seu habitat e duas espécies do mesmo gênero num único corpo d'água. Tais observações coadunam com o registro litológico e paleontológico da parte inferior da Formação Rio do Rasto, depositada em condições lacustres. A parte superior, onde há mais fácies eólicas e evidências de aumento de aridez, apresenta diversidade maior de conchostráceos, incluindo Hemicycloleaia mitchelli, uma espécie que permite realizar correlações cronoestratigráficos com a Austrália e Rússia. Sua idade provavelmente é neotatariana (=wuchiapingiana). Outros táxons, como Monoleiolophus unicostatus, também foram considerados nas correlações, estimando-se que a Formação Rio do Rasto esteja compreendida no Permiano médio-superior. Abstract: Conchostracans of the Rio do Rasto Formation (Paraná Basin, Permian) are revised and discussions based on experiments with living conchostracans are presented. One conclusion is that many carapace characteristics frequently used for classification change according to taphonomic, ecologic and ontogenetic factors. The conchostracans live in continental fresh waters and, on the contrary of some paradigms of the literature, the organisms are not restricted to ephemeral water bodies and tolerate the presence of predatory fishes and two species of one single genus. These observations combine well with the lithological and paleontological record of the lower Rio do Rasto Formation deposited under lacustrine conditions. The upper part, formed under more arid conditions, presents bigger conchostracan diversity and includes Hemicycloleaia mitchelli. This species may be used for wide correlations with Australia and Russia, and its age probably is Late Tatarian (= Wuchiapingian). Other taxa, as Monoleiolophus unicostatus, were also used for correlations and the age of the formation may be interpreted as mid to late Permian. Doutor

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Black, Manu School of Biological Earth &amp Environmental Sciences UNSW. "A late quaternary palaeoenvironmental investigation of the fire, climate, human and vegetation nexus from the Sydney basin, Australia." Awarded by:University of New South Wales. School of Biological, Earth and Environmental Sciences, 2006. http://handle.unsw.edu.au/1959.4/25745.

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It is widely believed that Australian Aboriginals utilised fire to manage various landscapes however to what extent this impacted on Australia???s ecosystems remains uncertain. The late Pleistocene/Holocene fire history from three sites within the Sydney Basin, Gooches Swamp, Lake Baraba and Kings Waterhole, were compared with archaeological and palaeoclimatic data using a novel method of quantifying macroscopic charcoal, which is presented in this study. The palynology and other palaeoecological proxies were also investigated at the three sites. The Gooches Swamp fire record appeared to be most influenced by climate and there was an abrupt increase in fire activity from the mid-Holocene perhaps associated with the onset of modern El Ni??o dominated conditions. The Kings Waterhole site also displayed an abrupt increase in charcoal at this time however there was a marked decrease in charcoal from ~3 ka. Lake Baraba similarly had displayed low levels of charcoal in the late Holocene. At both Kings Waterhole and Lake Baraba archaeological evidence suggests intensified human activity in the late Holocene during this period of lower and less variable charcoal. It is hence likely that at these sites Aboriginal people controlled fire activity in the late Holocene perhaps in response to the increased risk of large intense fires under an ENSO-dominated climate. The fire history of the Sydney Basin varies temporally and spatially and therefore it is not possible to make generalisations about pre-historic fire regimes. It is also not possible to use ideas about Aboriginal fire regimes or pre-historic activity as a management objective. The study demonstrates that increased fire activity is related to climatic variation and this is likely to be of significance under various enhanced Greenhouse scenarios. There were no major changes in the composition of the flora at all sites throughout late Pleistocene/Holocene although there were some changes in the relative abundance of different taxa. It is suggested that the Sydney Sandstone flora, which surrounds the sites, is relatively resistant to environmental changes. Casuarinaceae was present at Lake Baraba during the Last Glacial Maximum and therefore the site may have acted as a potential refugium for more mesic communities. There was a notable decline in Casuarinaceae during the Holocene at Lake Baraba and Kings Waterhole, a trend that has been found at a number of sites from southeastern Australia.

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Meira, Felipe van Enck. "Revisão sistemática e paleobiogeográfica de Trilobitas Phacopida (Homalonotidae e Calmoniidae) do Devoniano das Bacias do Parnaíba e Amazonas, Brasil." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/44/44141/tde-28092016-135646/.

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O conhecimento acerca dos invertebrados devonianos no Brasil teve início em fins do século XIX e a primeira metade do século XX, período no qual foram feitas expedições pioneiras às principais bacias paleozoicas do país - as bacias do Paraná, Parnaíba e Amazonas. Desta fase também resultaram importantes trabalhos científicos (e.g., Clarke, 1913), usados ainda hoje como referência em estudos. Dentre os trilobitas, os grupos mais representativos são os Homalonotidae e os Calmoniidae, cuja importância como ferramentas em questões paleoambientais e paleobiogeográficas vem sendo constatada a partir de recentes revisões sistemáticas em fósseis da Bacia do Paraná. Estes estudos também têm demonstrado que muitas das variações nos fósseis, interpretadas por pesquisadores anteriores como taxonômicas, decorrem de alterações tafonômicas, que podem levar a classificações errôneas. Neste contexto, o presente trabalho teve como objetivos revisar a sistemática dos trilobitas Phacopida (Homalonotidae e Calmoniidae) nas bacias do Parnaíba e Amazonas, incluindo, na primeira localidade, a nova ocorrência de São João Vermelho, no município de João Costa (PI), investigar, sempre que pertinente, a implicação das alterações tafonômicas na sistemática desses fósseis, identificando fatores diagenéticos/intempéricos que podem interferir nos caracteres morfológicos e discutir as implicações paleobiogeográficas dos Homalonotidae e Calmoniidae do Devoniano das bacias do Amazonas e Parnaíba, em relação a outras localidades adjacentes à estas bacias. Resultados das pesquisas mostram que a localidade de São João Vermelho é bastante promissora do ponto de vista paleontológico, pois consiste em uma nova localidade para o táxon M. tuberculatus, o qual também é documentado nas duas subbacias da Bacia do Paraná - Alto Garças e Apucarana, indicando que esta espécie apresenta alto grau de cosmopolitanismo. A análise de exemplares de Burmeisteria (Homalonotidae) desta localidade sugere que as diferenças nas espécies deste gênero no Brasil são mais sutis do que imaginado. Na Bacia do Amazonas, os Phacopida estão representados especialmente por Calmoniidae do gênero Malvinella, também presentes na Bolívia. As relações paleobiogeográficas entre as bacias paleozoicas brasileiras e a Bolívia, durante o Eo e Mesodevoniano, teriam sido mais estreitas do que se imaginava. A principal rota de migração para a Bacia do Parnaíba teria sido através da Bacia do Paraná, conforme constatado pela presença de M. tuberculatus. Já a migração para a Bacia do Amazonas teria se dado a sudoeste desta bacia, já que Malvinella ocorre apenas nesta bacia e na Bolívia The knowledge on Brazilian Devonian invertebrates started by the end of the 19th century and the first half of the 20th century, period which pioneering expeditions were made to the main Paleozoic basins of the country - Paraná, Parnaíba and Amazon basins. Important scientific contributions also resulted from this fase (e.g. Clarke, 1913), still used today as reference in studies. Among trilobites, the most representative groups are the Homalonotidae and Calmoniidae, whose importance in paleoenvironmental and paleobiogeographical questions have been noted from recent systematic revisions in Paraná Basin fossils. These studies also have demonstrated that many variations in fossils, interpreted by previous researchers as taxonomic, are due to taphonomic alterations, which can lead to erroneous classifications. In this context, the current study aimed to review the systematics of Phacopida trilobites (Homalonotidae and Calmoniidae) from the Parnaíba and Amazon basins, including, in the former locality, the new occurrence of São João Vermelho, in the João Costa municipality (PI); to investigate, whenever relevant, .the implication of the taphonomic alterations in the systematics of these fossils, identifying diagenetic/weathering factors which can interfere in the morphological features; and to discuss the paleobiogeographic implications of the Homalonotidae and Calmoniidae from the Devonian of the Parnaíba and Amazon basins, in relation to other localities adjacent to these basins. Study results show that the locality of São João Vermelho is paleontologically promising, as it consists of a new place for the M. tuberculatus taxon, which is also documented in the both Paraná Basin subbasins - Alto Garças and Apucarana, indicating that this species is highly cosmopolitan. The analysis of Burmeisteria (Homalonotidae) exemplars from this locality suggests that differences between the species of this genus in Brazil are slighter than thought. In the Amazon Basin, Phacopida trilobites are especially represented by the Calmoniidae genus Malvinella, also present in Bolivia. The paleobiogeographic relations between the Paleozoic Brazilian basins and Bolivia, during Early and Middle Devonian, would have been closer than thought. The main migration route to the Parnaíba Basin would have been through the Paraná Basin, as found by the presence of M. tuberculatus. The migration to the Amazon Basin, in turn, would have occurred southwestward this basin, as Malvinella occurs only in this locality and in Bolivia.

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Guillam, Elvis. "Les deux crises biologiques de la fin du Dévonien : les ostracodes marqueurs des variations paléoenvironnementales et des relations paléobiogéographiques." Electronic Thesis or Diss., Sorbonne université, 2023. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2023SORUS157.pdf.

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Au cours des temps géologiques, la vie s'est grandement complexifiée et a connu de nombreuses et importantes variations de biodiversité. Parmi les déclins du Phanérozoïque (-541.0 ± 1.0 Ma à actuel), cinq grandes crises sont considérées comme majeures. L'une d'elles, appelée événement Kellwasser, marque la limite entre le Frasnien et le Famennien (-372 ± 1.6 Ma). Elle est suivie à la transition Dévonien-Carbonifère par un second événement de premier ordre, appelé événement Hangenberg. Ces événements de nature anoxique auraient été déclenchés par les importants changements climatiques caractérisant le Dévonien supérieur et les variations eustatiques associées. Les ostracodes, microcrustacés essentiellement benthiques, sont connus pour leur registre fossile continu à travers tous les événements d'extinction ainsi que pour leurs capacités d'adaptation et sont de bons marqueurs des variations des paramètres environnementaux. Ce sont ainsi d'excellents outils pour comprendre les déclins de biodiversité lors des crises biologiques et la récupération des écosystèmes après ces déclins. L'important travail de taxinomie réalisée sur le matériel de la coupe de Blue Snake (Guizhou, Chine du Sud) a permis de quantifier de manière précise et pour la première fois les variations de diversité chez les ostracodes en lien avec l'événement Hangenberg et de caractériser le paléoenvironnement et ses variations à la transition Dévonien-Carbonifère. Sur cette coupe, le taux d'extinction spécifique est estimé à 44%. Sur cet intervalle, le paléoenvironnement correspondait à une plateforme continentale ayant subi une transgression, avec le passage d'un environnement littoral peu profond au Famennien à un milieu offshore au Tournaisien. Les révisions réalisées dans le cadre de cette thèse ont également permis de quantifier l'impact des événements Kellwasser et Hangenberg sur les ostracodes. Ces crustacés ont été grandement affectés à bas niveaux taxinomiques (espèces et genres) par ces deux événements avec des taux d'extinction spécifique estimé à 80% pour l'événement Kellwasser et 69% pour l'événement Hangenberg. Les niveaux supra-génériques ont été très peu touchés. Ces événements ont affecté la diversité de ces organismes dans divers paléoenvironnements (plateforme continentale interne et externe et milieux profonds) et dans de nombreuses zones paléogéographiques, démontrant le caractère global de ces extinctions. La récupération des faunes d'ostracodes à la suite de ces événements a certainement été influencée par les variations des paramètres environnementaux et climatiques. Elle est principalement caractérisée par la diversification de taxons cosmopolites, notamment au sein des Bairdiidae et des Bairdiocyprididae. Les Paraparchitidae se sont également diversifiés au cours du Tournaisien (Carbonifère inférieur). La distribution paléobiogéographique des ostracodes sur l'intervalle Frasnien-Tournaisien suggère que quatre facteurs principaux influencent leur répartition. Le climat, plus particulièrement la température, semble avoir influencé la distribution paléobiogéographique des ostracodes, la répartition des communautés identifiées suivant grossièrement la répartition latitudinale des climats. La circulation océanique pourrait expliquer les affinités observées entre les faunes provenant de zones paléogéographiques relativement éloignées. Le niveau marin et ses variations ainsi que la dynamique des plaques tectoniques semblent quant à eux avoir surtout influencé la connectivité globale entre les faunes des différentes zones paléogéographiques à l'échelle globale Over geological time, life has greatly increased in complexity and has undergone many important variations in biodiversity. Among the declines occurring during the Phanerozoic (541.0 ± 1.0 Ma to present), five major crises are considered as major. One of them, called the Kellwasser event, marks the Frasnian-Famennian boundary (-372 ± 1.6 Ma). It is followed at the Devonian-Carboniferous transition by a second first-order event, called Hangenberg event. These anoxic events have been triggered by important climatic changes and the associated eustatic variations characterizing the Late Devonian. Ostracods, essentially benthic microcrustaceans, are known for their continuous fossil record through all extinction events as well as for their adaptive capacities and are good markers of environmental changes. They are thus excellent tools for understanding biodiversity declines during biological crises and the recovery of ecosystems after these declines. The important taxonomic work realized on the material from the Blue Snake section (Guizhou, South China) allowed to quantify precisely and for the first time the diversity variations among ostracods related to the Hangenberg event and to characterize the paleoenvironment and its variations at the Devonian-Carboniferous transition. In this section, the specific extinction rate is estimated at 44%. Over this interval, the paleoenvironment corresponded to a continental shelf that underwent transgression, with the transition from a nearshore shallow environment in the Famennian to a deeper and more open offshore environment in the Tournaisian. The revisions realized during this thesis also allowed to quantify the impact of both Kellwasser and Hangenberg events on ostracods. These crustaceans were greatly affected at low taxonomic levels (species and genera) by both events with specific extinction rates estimated at 80% for the Kellwasser event and 69% for the Hangenberg event. The supra-generic levels were only slightly affected. These events affected the diversity of these crustaceans in various paleoenvironments (nearshore and outer-shelf and bathyal environments) and in numerous geographic areas, demonstrating the global character of these extinctions. The recovery of ostracod faunas following these events was certainly influenced by variations in environmental and climatic parameters. It is mainly characterized by the diversification of cosmopolitan taxa, notably within the Bairdiidae and Bairdiocyprididae. The Paraparchitidae also diversified during the Tournaisian (Lower Carboniferous). The palaeobiogeographic distribution of ostracods over the Frasnian-Tournaisian interval suggests that four main factors influence their repartition. Climate, especially temperature, seems to have influenced the palaeobiogeographic distribution of ostracods, with the identified communities roughly following the latitudinal distribution of climates. Oceanic circulation could explain the affinities observed between faunas from relatively distant palaeogeographical areas. The sea level and its variations as well as the tectonic plates dynamic had mainly influenced the global connectivity between the faunas from the different palaeogeographical areas on a global scale

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Souron, Antoine. "Histoire évolutive du genre Kolpochoerus (Cetartiodactyla : Suidae) au Plio-Pléistocèneen Afrique orientale." Thesis, Poitiers, 2012. http://www.theses.fr/2012POIT2306/document.

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La sous-famille des Suinae est largement répandue en Afrique au Plio-Pléistocène et a été abondamment utilisée pour corréler biochronologiquement les sites à hominidés en se basant sur l'évolution morphologique rapide des troisièmes molaires dans différentes lignées. À partir d'un échantillon important de suinés africains actuels, les schémas de variation morphologique crânio-mandibulaire et dentaire sont quantifiés par morphométrie géométrique. Ce référentiel actuel sert à estimer la variabilité morphologique dans le registre fossile. La révision de la paléobiodiversité du genre Kolpochoerus (le suiné plio-pléistocène le plus abondant) dans les bassins du Turkana et de l'Awash s'appuie sur l'étude anatomique et morphométrique de matériels publié et inédit découverts dans la basse vallée de l'Omo (formation de Shungura) et dans la vallée moyenne de l'Awash en Éthiopie. Une nouvelle espèce fossile est décrite, les trajectoires évolutives au sein de chaque espèce sont quantifiées, et les interprétations biostratigraphiques sont révisées. Les liens de parenté au sein du genre Kolpochoerus sont décrits grâce à l'analyse cladistique. L'étude de la paléoécologie des suinés africains est basée sur l'anatomie comparée et la biogéochimie des isotopes stables (carbone et oxygène). Les suinés fossiles présentent une gamme de taille importante, ainsi que des régimes alimentaires et des habitats variés. Les nouvelles connaissances acquises sur leur biodiversité, leur phylogénie, et leur écologie permettent de proposer une histoire paléobiogéographique des Suinae en Afrique The subfamily Suinae is widespread in Plio-Pleistocene deposits in Africa, and was heavily used as a biochronological tool to correlate hominid-bearing sites based on the rapid morphological evolution of third molars in different lineages. A large sample of extant African suines enables to quantify patterns of variation in cranio-mandibular and dental morphology using geometric morphometrics. This modern referential is used to estimate the morphological variability in the fossil record. Revision of the paleobiodiversity of the genus Kolpochoerus (the most abundant Plio-Pleistocene suine) in Turkana and Awash basins is based on anatomical and morphometric studies of published and unpublished material discovered in the Lower Omo Valley (Shungura Formation) and in the Middle Awash Valley in Ethiopia. A new fossil species is described, evolutionary trajectories within each species are quantified, and biostratigraphic interpretations are revised. Phylogenetic relationships within the genus Kolpochoerus are described by the cladistic analysis. Paleoecological study of African suines is based on comparative anatomy and stable isotopic biogeochemistry (carbon and oxygen). Fossil suines display a wide range of body size, as well as various diets and habitats. The new results produced regarding their biodiversity, phylogeny, and ecology, enable to reconstruct a paleobiogeographic history of Suinae in Africa

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Ribeiro, Victor Rodrigues. "Rotas migratórias de braquiópodes (família Leptocoeliidae & família Tropidoleptidae) das bordas devonianas das bacias do Paraná e Parnaíba /." Assis, 2019. http://hdl.handle.net/11449/191405.

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Orientador: Renato Pirani Ghilardi Resumo: A distribuição dos continentes no Devoniano era diferente do que temos atualmente. As bacias sedimentares que ocupavam as áreas próximas do Equador (e.g. Parnaíba, Amazonas, Solimões) hospedavam ecossistemas com uma grande diversidade de espécies. Por outro lado, as bacias que ocupavam regiões de alta latitude, como Paraná, hospedavam uma fauna de águas mais frias. Esta fauna, formalmente nomeada como Fauna Malvinocáfrica, é composta por uma diversidade baixa de Gastrópodes, Moluscos, Trilobitas e Braquiópodes (Australocoelia, Australospirifer, Australostrophia, Iridistrophia, Meristelloides, Derbyina, Lingula e Orbiculoidea).NaBaciadoParaná(Centro-Sulbrasileiro)afaunadevonianaestá retratada na Formação Ponta Grossa, já na Bacia do Parnaíba (Norte-Nordeste brasileiro) a fauna ocorre pontualmente, justamente devido às condições paleoambientais e climáticas. No Devoniano Médio, as bacias do Paraná e Parnaíba, em resposta a subida do nível do mar, passaram por um período de mistura faunística, justificada pela ocorrência de Tropidoleptus carinatus (espécie de mares equatoriais) no meio das faunas Malvinocáfricas da Bacia do Paraná. Com a finalidade de averiguar tais eventos de dispersão, foram levados em consideração os gêneros Tropidoleptus e Australocoelia, sendo um oriundo de mares quentes e outro de mares frios, respectivamente. Análises morfofuncionais dos exemplares, levantamentos bibliográficos e trabalhos de campo indicaram que espécies de braquiópodes... (Resumo completo, clicar acesso eletrônico abaixo) Abstract: The distribution of continents in the Devonian was different from what we have today. The sedimentary basins that occupied the areas near Ecuador (e.g. Parnaíba, Amazonas, Solimões) hosted ecosystems with a big diversity of species. On the other hand, basins that occupied high latitude regions, such as Paraná Basin, hosted a colder water fauna. This fauna, formally named as Malvinokaffric Realm, is composed of a low diversity of Gastropods, Molluscs, Trilobites and Brachiopods (Australocoelia, Australospirifer, Australostrophia, Iridistrophia, Meristelloides, Derbyina, Lingula and Orbiculoidea). In the Paraná Basin (Center-South Brazil) the Devonian fauna is portrayed in the Ponta Grossa Formation, while in the Parnaíba Basin (North-Northeast Brazil) the fauna occurs punctually, precisely due to paleoenvironmental and climatic conditions. In the Middle Devonian, the Paraná and Parnaíba basins, in response to sea level rise, underwent a period of faunal mixing, justified by the occurrence of Tropidoleptus carinatus (species from equatorial seas) in the middle of the Malvinokaffric faunas of the Paraná Basin. In order to investigate such dispersal events, the genera Tropidoleptus and Australocoelia were taken into consideration, one from warm seas and one from cold seas, respectively. Morphofunctional analyzes of the specimens, bibliographic surveys and fieldwork indicated that species of equatorial brachiopods did not enter the Paraná Basin, but were restricted to the temperat... (Complete abstract click electronic access below) Mestre

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Kornecki, Krystyna Maria. "CRETACEOUS CONFLUENCE IN THE COON CREEK FORMATION (MAASTRICHTIAN) OF MISSISSIPPI AND TENNESSEE, USA: TAPHONOMY AND SYSTEMATIC PALEONTOLOGY OF A DECAPOD KONSENTRAT-LAGERSTATTE." Kent State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=kent1409229777.

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Oliveira, Alessandro Marques de. "Megafauna cenozóica do Continente Americano : considerações sobre ecomorfologia, paleoecologia, evolução e paleobiogeografia." reponame:Repositório Institucional da UFABC, 2018.

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Orientador: Prof. Dr. Charles Morphy D. Santos Coorientadora: Profa. Dra. Mirian Liza Alves Foranceli Pacheco Tese (doutorado) - Universidade Federal do ABC, Programa de Pós-Graduação em Evolução e Diversidade, Santo André, 2018. A presente tese teve por objetivo contribuir para o conhecimento a respeito da megafauna do Cenozóico do continente Americano. O foco do trabalho foi o estudo da megafauna pleistocênica da América do Sul, para correlações paleobiogeográficas e paleoecológicas, e da superordem Xenarthra, para considerações sobre ecomorfologia. Para as análises ecomorfológicas, foi considerado um contexto geocronológico e geográfico mais amplo, incluindo nas análises espécimes tanto do Neógeno quanto do Quaternário da América do Sul e do Norte. Foram descritas novas ocorrências de fósseis de mamíferos de grande porte ¿ tais como preguiças gigantes, gliptodontes, gonfotérios, tigres-dente-de-sabre e ursídeos ¿ para o estado do Mato Grosso do Sul. As considerações paleobiogeográficas consitiram em uma tentativa de correlação da paleofauna do Pleistoceno da Serra da Bodoquena com outras regiões da América do Sul. Além disso, uma nova ocorrência de filhote fossilizado de Nothrotherium maquinense é reportada para o estado de São Paulo com posterior datação radiométrica e análise de isótopos de carbono. O segundo ponto abordado nesta tese incluiu estudos ecomorfológicos em Xenarthra fósseis e atuais com base no formato do úmero. Para este fim, foi aplicado o método de morfometria geométrica bidimensional e tridimensional. Os resultados obtidos mostram que a Serra da Bodoquena apresenta maior similaridade taxonômica com a Região Intertropical Brasileira, devendo, portanto, ser incluída neste contexto paleobiogeográfico. Também verificou-se a ocorrência de um segundo táxon de Nothrotheriinae e de Ursidae em território brasileiro, além de um terceiro táxon de Scelidotheriinae. Os resultados sobre N. maquinense no estado de São Paulo indicam que a espécie estava presente na região por volta dos 13 mil anos antes do presente, e que se alimentava de plantas C3, indicando a possibilidade da presença de ambientes mais úmidos na região. Do ponto de visto ecomorfológico, foi verificado que o úmero de Xenarthra é funcionalmente informativo, sendo possível distinguir indivíduos adaptados para modos de vida arborícolas, semiarborícolas, ambulatoriais e escavadores. Adicionalmente, foi contastado a influência do tamanho sobre o formato do úmero. The present thesis aimed to contribute to the knowledge about the Cenozoic Megafauna from the American continent. The focus was on both the Pleistocene Megafauna from South America, regarding paleobiogeographical correlations, and on the superorder Xenarthra, regarding considerations on ecomorphology. A broader geochronological and geographic context was considered to the ecomorphological analyses, including both Neogene and Quaternary specimens from South America and North America. The paleobiogeographical considerations were an attempt to correlate the Pleistocene paleofauna from Serra da Bodoquena to other South American regions. In addition, new occurrences of large mammal fossils ¿ such as giant sloths, glyptodonts, gomphotheres, felines and ursines ¿ were described for the state of the Mato Grosso do Sul. Additionally, a new occurrence of fossil cub identified as Nothrotherium maquinense was reported to the state of São Paulo. Dating and stable isotopes analyses were conduced. The second point addressed in this thesis includes ecomorphological studies on extant and extinct Xenarthrans based on the humerus shape. For this purpose, the bidimensional and tridimensional geometric morphometrics method were applied. The results showed that the Serra da Bodoquena presents greater taxonomic similarity to Brazilian Intertropical Region. Therefore, Mato Grosso do Sul should be included in this paleobiogeographical context. Additionally, the occurrence of a second Nothrotheriinae and Ursidae taxa, and a third Scelidotheriinae taxa was reported to Brazilian territory. The results on N. maquinense point out that such species was present in the region around 13 kya and it fed on C3 plants. This fact indicates the possibility of the presence of wetter environments in that region during late Pleistocene. From the ecomorphological point of view, it was verified that the Xenarthra humerus is functionally informative, being possible to distinguish individuals adapted to arboreal, semiarboreal, ambulatory and digger habitus. The influence of size on the humerus shape has been verified as well.

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37

Chaumeil, Rodriguez Micaela. "Calcareous nannofossils from Los Molles Formation, south of Huincul High, Neuquén Basin, Argentina : biostratigraphy and paleobiogeographic reconstructions for the Early to Middle Jurassic (Pliensbachian-Aalenian)." Electronic Thesis or Diss., Lyon 1, 2023. http://www.theses.fr/2023LYO10116.

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Les nannofossiles calcaires représentent un groupe diversifié de fossiles, remontant au Trias supérieur et s'étendant jusqu'à nos jours, caractérisés par leur composition calcaire et une taille inférieure à 30 µm. Parmi eux, les coccolithophoridés, qui constituent la fraction la plus importante du nannoplancton calcaire, c'est-à-dire des algues unicellulaires flagellées typiquement marins appartenant à la sous-classe Calcihaptophycidae, recouvertes de plaques de carbonate de calcium (coccolithes). Les représentants fossiles des coccolithophoridés correspond à leurs restes d'exosquelette, généralement conservés sous une forme désagrégée, comme des coccolithes individuels. Leur présence dans les océans est essentielle, car ils constituent l'un des principaux groupes de producteurs primaires marins. Les données géologiques suggèrent que les coccolithophoridés ont maintenu leurs exigences écologiques presque inchangées au fil du temps, et ainsi nous permettant de reconstruire de manière fiable les conditions paléoenvironnementales, paléobiogéographiques et paléoclimatiques. L'objectif général de cette thèse est d'étudier les associations de nannofossiles calcaires des sédiments marins du Jurassique inférieur-moyen au sud haut structural de Huincul du bassin de Neuquén (Argentine) et de combiner ces informations avec celles déjà disponibles afin d'élargir et d'améliorer les ressources biostratigraphiques du bassin. En comparant ces enregistrements avec des associations de nannofossiles calcaires provenant d'autres endroits du monde, nous visons à établir des corrélations d'âge globales et à évaluer les relations paléobiogéographiques, afin de générer un modèle biostratigraphique local. L'étude se concentre sur des échantillons provenant de trois sections d'affleurement et de deux forages d'exploration. Un total de 102 échantillons de surface et 111 échantillons de subsurface ont été étudiés. En outre, des analyses géochimiques (i.e. les isotopes stables du carbone, la matière organique totale et la composition élémentaire) ont été effectuées sur 384 échantillons d'affleurement. Des techniques de décantation aléatoire et de décantation par gravité ont été utilisées pour traiter les échantillons de nannofossiles. Le degré de similitude entre les associations de nannofossiles a été évalué en effectuant une analyse NMDS et une analyse UPGMA, en utilisant l'indice de similitude de Dice. La pyrolyse et la spectrométrie de masse du rapport isotopique ont été utilisées pour traiter les échantillons en vue de l'analyse de la matière organique totale et des isotopes stables, respectivement. Pour l'analyse élémentaire, la technique de diffraction des rayons X a été utilisée. Quarante-neuf espèces sont ici décrites, répartis dans neuf famillies et une espèce insertae sedis, dont cinq sont reconnues pour la première fois pour le bassin et le Pacifique sud-est. Six biozones et de nombreuses sous-zones sont reconnues en surface et subsurface, et sont en corrélation avec les schémas biostratigraphiques de la région de la Téthys. Elles correspondent au Pliensbachien à l'Aalénien moyen - Bajocien inférieur (NJT4–NJT9). Trois intervalles d'excursions isotopiques négatives accompagnées d'augmentations de la teneur en matière organique sont identifiés. Le premier d'entre eux est considéré comme l'équivalent temporel de le T-OAE. Les autres excursions de grande amplitude enregistrées au Toarcien moyen et dans l'intervalle Toarcien-Aalénien représentent le premier enregistrement de ce type pour l'intervalle Toarcien-Aalénien dans le bassin de Neuquén, et le deuxième enregistrement pour l'hémisphère sud. Les associations de nannofossiles calcaires du Pliensbachien sont liées à celles de la région de Téthys. Le Corridor hispanique est identifié comme la voie de dispersion des nannofossiles calcaires entre les océans Paléo-Pacifique et Téthys au cours du Jurassique inférieur, ce qui indique que son ouverture remonte au moins au début du Pliensbachien Calcareous nannofossils represent a diverse group of fossils, dating back to the Late Triassic and extending their record to the present day, characterised by their calcareous composition and a size under 30 microns. Among them oustand the coccolithophorids, which constitute the most important fraction of calcareous nannoplankton, i.e. flagellated unicellular algae belonging to the Subclass Calcihaptophycidae, covered by calcium carbonate plates (coccoliths), and typically marine inhabitants of the photic zone. The representation of coccolithophorids in the fossil record corresponds to their exoskeletal remnants, commonly preserved in a disaggregated form, as individual coccoliths. Their presence in the oceans is key as they are one of the main groups of marine primary producers. Evidence from the geological record suggests that coccolithophorids have maintained their ecological requirements almost invariant over time, making them key to reconstruct palaeoenvironmental, palaeobiogeographical and palaeoclimatic conditions. The aim of this thesis is to study the calcareous nannofossil associations of Early-Middle Jurassic marine sediments, south of the Huincul High, Neuquén Basin (Argentina). By combining this information with that already available, we seek to expand and improve the biostratigraphic resources of the basin, determine similarities with assemblages from other regions of the world, and evaluate the response of these organisms to important palaeoenvironmental events. The study focuses on samples from three outcrop sections —named El Matuasto I, II and III— and two exploratory boreholes —YPF.Nq.BCE.x-1 and YPF.Nq.PTU.x-2—. A total of 102 surface samples, 20 core samples and 91 drill cuttings samples were studied. In addition, geochemical analyses (i.e., stable carbon isotopes, total organic matter and elemental composition) were performed on 384 outcrop samples. Random settling and gravity settling techniques were used to process the calcareous nannofossil samples. Quantitative analysis of nannofossils required counting at least 300 individuals; in case of a sample with low abundance, counting stopped at 450 fields of view. The degree of similarity between nannofossil associations was assessed by running NMDS and UPGMA analyses, both using the Dice index. Pyrolysis and isotope ratio mass spectrometry were used to process samples for total organic matter and stable isotope analysis, respectively. For the elemental analysis, the X-ray diffraction technique was executed. In all cases, samples containing shell remains and/or evidence of weathering were avoided. Forty-nine species are described, distributed in nine families and one species insertae sedis, of which five are recognised for the first time for the basin and the southeast Pacific area, and most of them are illustrated. Six biozones and numerous subzones are recognized on the surface and subsurface sections and correlate with biostratigraphic schemes of the Tethys region. These correspond to the Pliensbachian (Biozone NJT4) to the middle Aalenian - early Bajocian (Biozone NJT9). Three intervals of negative isotopic excursions accompanied by increases in organic matter content are identified. Applying the biostratigraphic framework, the first of these is considered to be the time-equivalent of the Toarcian Oceanic Anoxic Event (T-OAE). The other high-amplitude isotope excursions recorded in the middle Toarcian and in the Toarcian-Aalenian interval represent the first record of their kind for the Toarcian - Aalenian interval in the Neuquén Basin, and the second record for the southern hemisphere. The Pliensbachian calcareous nannofossil associations recognized in one of the sections are biogeographically related to those of the Tethys region. The Hispanic Corridor is identified as the pathway of calcareous nannofossil dispersal between the Pacific and Tethys oceans during the Early Jurassic, indicating its time of opening at least from the early Pliensbachian

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38

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 dérivés Perissodactyls (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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39

Klingensmith, Brandon C. "GIS Based Biogeography of Cincinnatian (Upper Ordovician) Brachiopods with Special Reference to Hebertella." Ohio University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1312925741.

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40

Boucher, Lisa Diane. "Morphometric and Paleobiogeographic Analyses of Dicroidium from the Triassic of Gondwana /." The Ohio State University, 1995. http://rave.ohiolink.edu/etdc/view?acc_num=osu148792974533245.

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41

Guerra, Rodrigo do Monte. "Nanofósseis calcários do Campaniano e Maastrichtiano no Atlântico Sul: bioestratigrafia, paleoceanografia e paleobiogeografia." Universidade do Vale do Rio dos Sinos, 2016. http://www.repositorio.jesuita.org.br/handle/UNISINOS/5721.

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Submitted by Silvana Teresinha Dornelles Studzinski (sstudzinski) on 2016-09-21T15:45:10Z No. of bitstreams: 1 Rodrigo do Monte Guerra_.pdf: 12842392 bytes, checksum: b6db9de51a65dd59c144edac22f16cab (MD5) Made available in DSpace on 2016-09-21T15:45:10Z (GMT). No. of bitstreams: 1 Rodrigo do Monte Guerra_.pdf: 12842392 bytes, checksum: b6db9de51a65dd59c144edac22f16cab (MD5) Previous issue date: 2016-01-19 CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Milton Valente O final do período Cretáceo é caracterizado por uma gradual transição climática de escala global, fator que modificou a composição das assembleias de nanofósseis calcários e por conta disso vem causando problemas nas interpretações bioestratigráficas entre diferentes faixas latitudinais. Apesar de possuir alguns estudos realizados principalmente entre as décadas de 1980 e 1990, existe uma carência na avaliação do Atlântico Sul como um todo. Desta forma, este estudo objetiva descrever as assembleias de nanofósseis calcários comuns em cada faixa latitudinal e testar o sincronismo dos principais bioeventos. Foram analisadas 649 amostras provenientes de doze seções testemunhadas pelos projetos Deep Sea Drilling Project (DSDP) e Ocean Drilling Program (ODP) nas proximidades da margem brasileira e africana, além de um afloramento na Península Antártica. O estudo taxonômico possibilitou a identificação de 197 espécies de nanofósseis calcários do Campaniano e Maastrichtiano. Através do uso conjunto da bioestratigrafia e magnetoestratigrafia, foram reconhecidos diacronismos em eventos de primeira e última ocorrência de espécies do Campaniano superior e Maastrichtiano superior. Este diacronismo está relacionado a migrações de espécies entre baixas e médias latitudes, decorrentes de mudanças na circulação oceânica e temperatura das águas superficiais. Com base na variação latitudinal das assembleias de nanofósseis calcários, um detalhado estudo bioestratigráfico possibilitou a divisão de três zoneamentos para o Atlântico Sul (baixas, médias e altas latitudes). Além disso, foram definidos os padrões de distribuição de diversas espécies, mostrando uma clara divisão paleobiogeográfica entre espécies que ocorrem somente em latitudes altas e outras limitadas a latitudes médias a baixas. Este padrão possivelmente foi controlado por variações na temperatura das massas de água superficiais. Outras espécies possuem sua distribuição variada em todas as faixas latitudinais, tendo sua distribuição relacionada provavelmente à disponibilidade de nutrientes. The Late Cretaceous period is characterized by global climatic transition that influenced calcareous nannofossil assemblages posing a challenge for biostratigraphic interpretation between different latitudinal degrees. There are a few studies on South Atlantic calcareous nannofossils from 1980 and 1990 decades, but none of them evaluate the South Atlantic as a whole. Therefore, this study aims to describe the calcareous nannofossils assemblages in each latitudinal zone and test the bioevents synchroneity. It were selected 649 samples from twelve cored sections coming from DSDP (Deep Sea Drilling Project) e ODP (Ocean Drilling Program) close to the Brazilian and African margins, in addition to an outcrop in the Antarctic Peninsula. The taxonomic study allowed the identification of 197 calcareous nannofossils species from the Campanian and Maastrichtian. Using the correlation between the biostratigraphical data and magnetostratigraphy, it was possible to identify diachronism in some bioevents of first and last occurrences during the late Campanian and late Maastrichtian. This diachronism is related to species migration between low and mid-latitudes, due to changes in the ocean circulation and surface water temperature. Based on the latitudinal variation in the calcareous nannofossils assemblages, a detailed biostratigraphic study enabled the South Atlantic division in three zonations (low, medium and high-latitudes). We also defined the distribution pattern of some species, indicating a clear paleobiogeographical division between high latitude species and some species limited to low and mid-latitudes. This pattern was possibly controlled by surface water temperature variation. Other species have a wide distribution across the latitudes probably related to nutrient availability.

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42

Bauer, Jennifer E. "A Phylogenetic and Paleobiogeographic Analysis of the Ordovician Brachiopod Eochonetes." Ohio University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1397486053.

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43

Mazin, Jean-Michel. "Paleobiogeographie des reptiles marins du trias : phylogenie, systematique, ecologie et implications paleobiogeographiques." Paris 6, 1988. http://www.theses.fr/1988PA066683.

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Les trois groupes de reptiles marins du trias, ichthyopterygiens, sauropterygiens et placodontes, sont analyses globalement. Leur revision aboutit a reconnaitre 114 especes valides pour lesquelles une analyse phylogenetique est proposee. Les caracteristiques ecologiques (locomotion, regimes alimentaires) des trois groupes sont etudiees afin de determiner leurs potentialites de dispersion. La confrontation de leur distribution geographique et de ces potentialites de dispersion, aux reconstitutions paleogeographiques du trias conduisent a proposer plusieurs modeles de dispersion

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44

Suraprasit, Kantapon. "Paléoenvironnements et reconstitutions paléoclimatiques du Pléistocène moyen de Thaïlande et leur impact sur la biodiversité et la distribution des espèces : la contribution de la faune de vertébrés du gisement de Khok Sung (Province du Khorat)." Thesis, Poitiers, 2015. http://www.theses.fr/2015POIT2285/document.

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La sablière de Khok Sung, dans la province de Nakhon Ratchasima, qui a livré plus d'un millier de fossiles de mammifères et de reptiles (cranes, dents isolées et restes post-craniens), abrite la faune de vertébrés du Pléistocène la plus riche de Thaïlande. La faune mammalienne qui est décrite ici en détail, se compose d'au moins 18 espèces identifiées (12 genres), y compris un primate et des proboscidiens, rhinocéros, suidés, bovidés, cervidés et carnivores. Elle compte principalement des taxons encore représentés de nos jours, ainsi que quelques taxons globalement ou localement éteints. A partir des données paléomagnétiques et des comparaisons fauniques, l'âge de la faune de Khok Sung est estimé au Pléistocène Moyen tardif, vers 188000 ou 213000 ans. Par rapport aux autres faunes diversifiées du Pléistocène d'Asie du Sud Est, l'assemblage de Khok Sung est caractérisé par une association des taxons Stegodon-Ailuropoda, comparable en cela au site de Thum Wiman Nakin, ce qui supporte l'hypothèse selon laquelle le Nord Est de la Thaïlande était un corridor biogéographique appartenant à la route migratoire Sino-Malaise, entre la Chine du Sud et l'île de Java. L'analyse des isotopes stables du carbone à partir de l'émail des ongulés fossiles révèle la présence d'une partition de niches entre les méga-herbivores et au sein des cervidés. Les valeurs du d13C de l'émail suggèrent également que les ruminants ont consommé une grande quantité de plantes en C4, ce qui indique que les prairies à graminées étaient particulièrement répandues en Thaïlande à cette époque où les écosystèmes n'étaient pas encore soumis à l'influence anthropique. La mesure des isotopes stables de l'oxygène, obtenue par échantillonnage sérié de l'émail des dents de grands mammifères, et l'analyse du cénogramme de la localité de Khok Sung reflètent une importante variation saisonnière des précipitations et de la température, associée à des conditions climatiques relativement humides The Khok Sung sand pit, Nakhon Ratchasima province, has yielded the richest Pleistocene vertebrate fauna of Thailand, where more than a thousand fossil mammals and reptiles (skulls, isolated teeth, and postcranial remains) were recovered. The mammalian fauna, which is described in details hereby, consists of at least 18 identified species (12 genera), including a primate, proboscideans, rhinoceroses, suids, bovids, cervids, and carnivores, which are characterized by mostly extant elements associated to some completely and locally extinct taxa. The age of the Khok Sung fauna is tentatively attributed to the late Middle Pleistocene as either 188 or 213 ka, based on the paleomagnetic data and on the faunal comparisons. The Khok Sung mammal assemblage yields the Stegodon-Ailuropoda faunal association, most similar in composition to that of Thum Wiman Nakin, supporting the hypothesis that northeastern Thailand was a biogeographic gateway of the Sino-Malayan migration route from South China to Java. An analysis of stable carbon isotopes extracted from the tooth enamel of fossil ungulates reveals evidence of niche partitioning among megaherbivores and within cervids. The enamel carbonate d13C values also suggest a considerable amount of C4 plants in the dietary use of ruminants, indicating that grasslands had significantly expanded in Thailand at that time during which anthropic impacts on the ecosystems were absent. The stable oxygen isotope results, obtained from the serial sampling of large mammal enamel, combined with the cenogram analysis reflect significant seasonal variation in precipitations and temperature for Khok Sung, associated to a relatively humid climate

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45

Ito, Tsuyoshi. "External and internal craniofacial morphology of Asian macaques and its evolutionary and paleobiogeographic implications." 京都大学 (Kyoto University), 2012. http://hdl.handle.net/2433/157833.

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46

Breton, Gérard. "Les goniasteridae (asteroidea, echinodermata) jurassiques et cretaces de france : taphonomie, systematique, biostratigraphie, paleobiogeographie, evolution." Caen, 1990. http://www.theses.fr/1990CAEN2034.

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Les goniasteridae mesozoiques etudies dans ce travail se repartissent entre 21 genres (4 nouveaux) et 72 especes ou sous-especes (24 nouvelles). Les marginales isolees portent suffisamment de caracteres pour etre representatives de l'holomorphe de l'espece. La repartition biostratigraphique et la distribution paleogeographique de ces especes sont precisees. Phylogenie descriptive et explicative: rapports phyletiques entre les genres, emergence des genres (geniation), rythme de l'evolution, pedomorphoses et canalisation, peramorphocline de metopaster gr. Loirensis. Une cle de determination est proposee

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47

Lam, Adriane R. "Paleobiogeographic Analyses of Late Ordovician Faunal Migrations: Assessing Regional and Continental Pathways and Mechanisms." Ohio University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1428515661.

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48

Pelletier, Maxime. "Evolution morphométrique et biogéographie des léporidés dans les environnements méditerranéens au Pléistocène : implications socio-économiques pour les sociétés humaines." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0226.

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En Europe de l’Ouest, de nombreuses espèces de léporidés sont endémiques, ce qui en fait de bons témoins de l’évolution des écosystèmes terrestres dans lesquelles ont évolué les sociétés humaines préhistoriques. Paradoxalement, leur variabilité morphologique est mal connue et la phylogénie établie aujourd’hui, discutable. Ce travail propose de renseigner la diversité morphométrique des lapins et des lièvres sur près de deux millions d’années d’évolution, à travers l’application d’études ostéométriques et en morphométrie géométrique. L’analyse de restes osseux et dentaires – de populations actuelles et de 73 séries fossiles provenant de régions périméditerranéennes couvrant le Pléistocène – permet de caractériser les adaptations des léporidés face aux changements environnementaux et leurs tendances évolutives. Cette étude propose une nouvelle phylogénie pour le lapin et présente les différentes phases de dispersion des taxons à l’échelle de l’Europe occidentale. Ainsi, plusieurs événements de type expansion des populations, recolonisation des territoires depuis des zones refuges et extinctions locales, sont mis en évidence en réponse aux changements climatiques globaux. Ces résultats permettent de discuter la présence de ces petits gibiers dans l’environnement et alimente le débat sur les relations entre ces espèces et les communautés humaines. Leur augmentation significative dans la diète des groupes humains à la fin du Paléolithique supérieur, ne semble pas seulement s’expliquer par des changements cognitifs, culturels ou économiques, mais coïncide davantage avec les variations biogéographiques de ces espèces Fossil remains of small mammals of the Leporidae family are abundant in numerous paleontological and archaeological deposits from the Quaternary. Many species are endemic to Western Europe, which makes them reliable markers of change in the ecosystems in which prehistoric human societies evolved. Paradoxically, morphological variability of leporids is still poorly understood and current phylogeny remains a subject of debate. This work focuses on the morphometric diversity of rabbits (Oryctolagus) and hares (Lepus) over nearly two million years of evolution. We applied osteometry and geometric morphometric analyzes to bone and dental remains of current populations and 73 fossil samples from perimediterranean regions (Spain, France, Italy, Portugal) during different moments of the Pleistocene. These data provide insights concerning Leporidae adaptations to environmental change as well as more general evolutionary trends. Here we propose a new phylogeny for the genus Oryctolagus and present different dispersion phases for Western Europe. Several population expansion events coupled with the recolonization of refuge areas and local extinctions are highlighted in response to global climate change. These results allow us to discuss the presence of these small game species in the environment and contribute to the debate concerning relations between leporids and human communities. Humans have regularly consumed leporids since at least the Middle Paleolithic. Their significant increase in the diet at the end of the Upper Paleolithic, however, cannot be explained solely by cognitive, cultural or economic changes but rather coincides with biogeographic variations of these species

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49

Coillot, Tiphaine. "Paléoclimats et biodiversité : apport des Equidae à la connaissance des modifications paléoenvironnementales et paléoclimatiques en Afrique au cours des premières phases de l'histoire de l'homme (entre 7 Ma et 1 Ma)." Thesis, Poitiers, 2014. http://www.theses.fr/2014POIT2326.

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Les équidés, groupe à grande répartition géographique et emblématique de la macroévolution, sont largement documentés. Leur taxonomie est pourtant très sujette à controverse résultant en de nombreuses synonymies, en général à cause d'un manque d'informations sur la valeur diagnosique des caractères. Les hipparions et Equus africains, représentés majoritairement par du matériel dentaire isolé, restent méconnus par rapport aux taxons nord-américains et eurasiatiques dont les spécimens sont souvent plus complets. Afin de déterminer le domaine de variation des caractères dentaires (variation ontogénétique, intra- et interspécifique, et prémolaires / molaires), une analyse de morphométrie géométrique combinée avec de l'imagerie 3D et/ou des mesures biométriques est testée pour la première fois sur les espèces actuelles d'Equus. Les résultats sont ensuite utilisés pour déterminer ou réviser le matériel fossile de sites à hominidés tchadiens (secteurs fossilifères datés à 7 Ma ; 5,4 Ma ; 4 Ma ; et 3,6 Ma) et éthiopiens (Formation de Shungura, continue de 3,6 Ma à 1,05 Ma et documentant la première apparition d'Equus en Afrique à 2,27 Ma). Une phylogénie basée sur une majorité de caractères dentaires est enfin testée, et sert de base pour discuter les relations phylogénétiques et la paléobiogéographie de ces taxons. Une étude morpho-fonctionnelle, qui sera ultérieurement couplée à d'autres analyses paléoécologiques, utilise les équidés (considérés généralement comme marqueurs de milieux ouverts mais pouvant présenter des régimes alimentaires variés) comme indicateurs des paléoenvironnements. L'étude des équidés est donc importante dans un cadre chronologique comprenant des changements fauniques et environnementaux notables, liés à l'émergence des hominidés Equids, that have a wide geographic distribution and that are an emblematic model of macroevolution, are well documented. Their taxonomy is however unclear, leading to a rampant synonymy often due to a lack of information on the diagnostic validity of characters. African hipparions and Equus, represented mainly by isolated dental material, remain little known compared to North American and Eurasian taxa displaying often more complete specimens. In order to assess the range of variation of dental characters (ontogenetic variation, intra- and interspecific variation, and variation between premolars and molars), a geometric morphometrics analysis combined with 3D imaging and/or biometric measurements is tested for the first time on extant species of Equus. Results are then used to determine or revise the fossil material from hominid-bearing sites of Chad (7 Ma, 5.4 Ma, 4 Ma, 3.6 Ma) and Ethiopia (Shungura Formation, continuous and dated from 3.6 Ma to 1.05 Ma, and that documents the first occurrence of Equus in Africa at 2.27 Ma). A phylogenetic analysis based on a majority of dental characters is then tested and allows discussing the phylogenetic relationships and paleobiogeography of these taxa. A morpho-functional study, which will later be coupled with other paleoecological analyzes, uses equids (generally considered as markers of open areas but that may display diversified diets) as a proxy for paleoenvironments. The study of equids appears therefore important in a chronological framework including significant faunal and environmental changes associated with the emergence of hominids

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50

Bartholomew, Alexander Jess. "Middle devonian faunas of the Michigan and Appalacian basins comparing patterns of biotic stability and turnover between two paleobiogeographic subprovinces /." Cincinnati, Ohio : University of Cincinnati, 2006. http://www.ohiolink.edu/etd/view.cgi?acc%5Fnum=ucin1156046845.

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Abstract (sommario):

Thesis (Ph. D.)--University of Cincinnati, 2006. Title from electronic thesis title page (viewed Jan. 26, 2007). Includes abstract. Keywords: Coordinated Stasis, Faunal Stability, Faunal Turnover, Middle Devonian, Sequence Stratigraphy, Eifelian, Givetian, Michigan Basin, Appalachian Basin. Includes bibliographical references.

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Tesi sul tema "Paleobiogeography"

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