Thesis (Ph. D.)--University of Washington, 1982. / Vita. Bibliography: leaves 235-255.

Thesis--Columbia University. / Bibliography: p. 559-562.

Thesis (Ph. D.)--University of Chicago, Dept. of Organismal Biology and Anatomy, August 1999. / Includes bibliographical references. Also available on the Internet.

Thesis (M.Sc)--University of Adelaide, Dept. of Geology, 1983. / Typescript (photocopy). 12 fold. plans in end pocket. Includes bibliographical references.

Made available in DSpace on 2016-01-13T13:27:04Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-04-17. Added 1 bitstream(s) on 2016-01-13T13:32:23Z : No. of bitstreams: 1 000855485.pdf: 7534024 bytes, checksum: 3199f68c4c86807d828a2b5a85013760 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Amphisbaenia é um importante grupo de amniotas reptilianos, providos de corpo cilíndrico e alongado, usualmente desprovidos de membros, com a exceção da Família Bipedidae, que apresentam os anteriores desenvolvidos. Esta anatomia facilita a vida fossorial. São alocados aos Squamata, por possuírem hemipênis, dente para romper e sair do ovo, cloaca transversal e tegumento coberto de escamas. Por assemelharem-se a lacertílios e ofídios, seu posicionamento filogenético tem sido amplamente discutido e sua ancestralidade é ainda controversa. São limitados às regiões subtropicais e tropicais, constituindo importante informação para abordagens paleoecológicas e paleobiogeográficas. Confeccionam profundos túneis compactando o solo, o que implica em grandes modificações morfológicas, tais como crânio robusto, formado por placas ósseas rígidas, e ligações interdigitais na região frontal, podendo ser sobrepostas, o que lhes confere maior resistência contra impactos na escavação. Sua anatomia é bastante convergente com aquela dos fósseis de lacertiformes mesozóicos, demonstrando um provável ancestral em comum com estes diápsidos. Um espécimen de Cryptolacerta, oriundo da Alemanha, compartilha características com Amphisbaenia. Entretanto sua filogenia ainda é incerta. De todo modo, junto com Sineoamphisbaena, pode indicar características convergentes entre lagartos laurasianos, possivelmente com aqueles que originaram Amphisbaenia. Os fósseis de anfisbênios são geograficamente restritos, predominantemente encontrados nos Estados Unidos, em quantidade relativamente escassa. A maior parte está relacionada à Família Rhineuridae, que poderia ser considerada primitiva. No entanto Bipedidae, um grupo recente, também é considerado como primitivo, devido à presença de cintura escapular e membros anteriores. Entretanto não há registros fósseis seguros, pois até então não foram encontrados restos fossilizados.. / Amphisbaenia is an important group of reptilian amniotes, provided with cylindrical and elongated body, usually limbless, with the exception of the Family Bipedidae, which presents limbs. This anatomy facilitates fossorial life. They are allocated to Squamata, by having hemipenis, tooth to break the egg, cross cloacal vent and integument covered with scales. Resembling lacertilians and snakes, their phylogenetic position has been widely discussed and their ancestry is still controversial. They are limited to subtropical and tropical regions, providing important paleoecological and paleobiogeographical informations to the group. They cave deep tunnels, compacting soil, which implies major morphological changes, such as robust skull bones, with rigid plates, and strong osteological connections in the frontal region, with superimposed bones, giving them greater resistance to impacts during excavation. Their anatomy is quite convergent with Mesozoic lacertiform fossils, showing a probable common ancestor with these diapsids. A specimen of VIII Cryptolacerta, from Germany, shares features with Amphisbaenia. However its phylogeny is still uncertain. But Sineoamphisbaena may indicate convergent features between Laurasian lizards, possibly with those originated Amphisbaenia. The fossil records are geographically restricted, predominantly from USA, in relatively small quantity. Most are related to the Family Rhineuridae, which could be considered primitive. However the Family Bipedidae, a recent group, is classified also as primitive, due to the presence of shoulder girdle and forelimbs. But Bipedidae does not present fossils, because until now there are not fossilized remains assigned to them. Morphological convergence occurs in Rhineuridae, detailed in phylogenetic analyses, placing it as a apomorphic group. Anyway it is clear that the origin of Amphisbaenia remains obscure. There are not well preserved fossil materials before beginning of Eocene

Orientador: Reinaldo José Bertini / Banca: Maria Eliana Carvalho Navega Gonçalves / Banca: Silvia Regina Gobbo Rodrigues / Resumo: Amphisbaenia é um importante grupo de amniotas reptilianos, providos de corpo cilíndrico e alongado, usualmente desprovidos de membros, com a exceção da Família Bipedidae, que apresentam os anteriores desenvolvidos. Esta anatomia facilita a vida fossorial. São alocados aos Squamata, por possuírem hemipênis, dente para romper e sair do ovo, cloaca transversal e tegumento coberto de escamas. Por assemelharem-se a lacertílios e ofídios, seu posicionamento filogenético tem sido amplamente discutido e sua ancestralidade é ainda controversa. São limitados às regiões subtropicais e tropicais, constituindo importante informação para abordagens paleoecológicas e paleobiogeográficas. Confeccionam profundos túneis compactando o solo, o que implica em grandes modificações morfológicas, tais como crânio robusto, formado por placas ósseas rígidas, e ligações interdigitais na região frontal, podendo ser sobrepostas, o que lhes confere maior resistência contra impactos na escavação. Sua anatomia é bastante convergente com aquela dos fósseis de lacertiformes mesozóicos, demonstrando um provável ancestral em comum com estes diápsidos. Um espécimen de Cryptolacerta, oriundo da Alemanha, compartilha características com Amphisbaenia. Entretanto sua filogenia ainda é incerta. De todo modo, junto com Sineoamphisbaena, pode indicar características convergentes entre "lagartos" laurasianos, possivelmente com aqueles que originaram Amphisbaenia. Os fósseis de anfisbênios são geograficamente restritos, predominantemente encontrados nos Estados Unidos, em quantidade relativamente escassa. A maior parte está relacionada à Família Rhineuridae, que poderia ser considerada primitiva. No entanto Bipedidae, um grupo recente, também é considerado como primitivo, devido à presença de cintura escapular e membros anteriores. Entretanto não há registros fósseis seguros, pois até então não foram encontrados restos fossilizados.. / Abstract: Amphisbaenia is an important group of reptilian amniotes, provided with cylindrical and elongated body, usually limbless, with the exception of the Family Bipedidae, which presents limbs. This anatomy facilitates fossorial life. They are allocated to Squamata, by having hemipenis, tooth to break the egg, cross cloacal vent and integument covered with scales. Resembling lacertilians and snakes, their phylogenetic position has been widely discussed and their ancestry is still controversial. They are limited to subtropical and tropical regions, providing important paleoecological and paleobiogeographical informations to the group. They cave deep tunnels, compacting soil, which implies major morphological changes, such as robust skull bones, with rigid plates, and strong osteological connections in the frontal region, with superimposed bones, giving them greater resistance to impacts during excavation. Their anatomy is quite convergent with Mesozoic lacertiform fossils, showing a probable common ancestor with these diapsids. A specimen of VIII Cryptolacerta, from Germany, shares features with Amphisbaenia. However its phylogeny is still uncertain. But Sineoamphisbaena may indicate convergent features between Laurasian "lizards", possibly with those originated Amphisbaenia. The fossil records are geographically restricted, predominantly from USA, in relatively small quantity. Most are related to the Family Rhineuridae, which could be considered primitive. However the Family Bipedidae, a recent group, is classified also as primitive, due to the presence of shoulder girdle and forelimbs. But Bipedidae does not present fossils, because until now there are not fossilized remains assigned to them. Morphological convergence occurs in Rhineuridae, detailed in phylogenetic analyses, placing it as a apomorphic group. Anyway it is clear that the origin of Amphisbaenia remains obscure. There are not well preserved fossil materials before beginning of Eocene / Mestre

With the transition from water to land in early tetrapods, and with transitions to secondarily aquatic habits in numerous tetrapod lineages, the functions of the vertebral column were transformed. Morphological changes in the vertebral column are a major mechanism by which vertebrates accommodate changes in locomotor forces. Although morphometric measurements from vertebrae have been correlated with axial mechanics and locomotor behaviour in numerous extant taxa, few studies have sought to test or apply these principles in non-mammalian tetrapods. In my thesis, I reconstructed the vertebral mechanics of fossil taxa that represent intermediate stages in water/land transitions of their lineages. Study taxa were the basal tetrapod Pederpes finneyae, which is one of the earliest known tetrapods to show indications of terrestrial adaptation, and three extinct crocodylomorphs, Terrestrisuchus, Protosuchus, and Pelagosaurus, which span the spectrum from fully terrestrial to primarily aquatic. I used a combination of morphometric measurements and 3D virtual models of bone morphology to estimate intervertebral joint stiffness and range of motion. For comparison, I also reconstructed the vertebral mechanics of four related extant taxa. Correlations between vertebral morphometrics and axial stiffness were statistically tested in (cadaveric) modem crocodylians, and I validated my methodology by comparing my results with data from extant taxa. My results reveal similarities and differences between the two lineages. Intervertebral joint compliance and range of motion tended to decrease with adaptation for terrestrial locomotion, as expected, but this trend seems to have reversed in later forms. Additionally, vertebral mechanics may have been largely controlled by different structural mechanisms in different lineages. The relationship between biomechanics of vertebrae and environment appears to be more complex than previously supposed. However, approaches that combine experimental measurements from extant animals, thorough analysis of fossil morphology, and explicit phylogenetic considerations have the potential to greatly improve locomotor reconstructions of extinct taxa.

No description available.

Thesis (Ph.D.) -- La Trobe University, 2006. / "A thesis submitted in total fulfilment of the requirements for the degree of Doctor of Philosophy, Dept. of Zoology, School of Life Sciences, La Trobe University". Research. Includes bibliographical references (p. 445-481). Also available via the World Wide Web.

Jawed vertebrates (gnathostomes) account for over 99% of living vertebrate diversity, with origins that stretch back nearly half a billion years, and comprise two groups: Osteichthyes (fishes and land-dwelling vertebrates) and Chondrichthyes (sharks, rays and chimaeras). Osteichthyans are the dominant clade, with at least 60,000 species approximately evenly divided between two clades: the Actinopterygii and the Sarcopterygii. However, our understanding of early osteichthyan evolution is skewed in favour of sarcopterygians, leaving the origin of nearly half of all vertebrate diversity critically understudied. Furthermore, recent upheavals in the early gnathostome tree have destabilised relationships amongst fossil taxa and eroded our understanding of primitive anatomical conditions of key groups. Central to understanding early gnathostome evolution is the braincase, an anatomically complex structure that provides a wealth of morphological characters. However, braincases rarely fossilise, and their position inside the skull makes them difficult to attain. X-ray tomography allows a comprehensive description of the internal and external anatomy of fossils, including the braincase. This thesis sets out to target phylogenetically pivotal taxa and incorporate new anatomical data in building up a picture of character evolution in early jawed vertebrates. In particular, I target the gnathostome stem, describing a new taxon that helps bridge the morphological gap between placoderms and crown gnathostomes, allowing a more comprehensive understanding of both dermal and endoskeletal evolution. I also focus on early actinopterygians, describing the endoskeleton of the first members of the group in order to understand primitive anatomical conditions. I then investigate actinopterygian braincase anatomy in the context of a revised phylogenetic analysis, illuminating the early evolution of the actinopterygians. Finally, I present a synthetic review of braincase anatomy across the early gnathostome tree. These results provide a more accurate picture of braincase evolution across gnathostomes and actinopterygians, clarifying our understanding of their evolution while revealing new information about when key innovations arose in the brains of the very first ray-finned fishes.