Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 13 of 13 for “"squamate"”.
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Historical Processes and Genetic Implications of Limb Reduction and Loss in an Island Skink Lineage
… the most comprehensive, fine-scale analyses of squamate body-form evolution to date, introducing a new model system of closely related, morphologically variable, lizards. In this study I provide the first robust estimate of phylogenetic relationships within the genus Brachymeles using a …
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Localization of Calbindin-D<sub>28k</sub> in Extra-Embryonic Membranes of Two Oviparous Scincid Lizards.
… membrane and yolk sac of oviparous squamate reptiles (lizards and snakes) transport calcium from the eggshell and yolk to the developing embryo. I used immunohistochemistry to localize calbindin-D<sub>28K</sub> expression in the chorioallantoic membrane and yolk sac of two species of …
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The damaging potential of pesticide formulations on human skin
… surfactants. An alternative membrane, shed squamate skin was shown to be an unsuitable model for human skin damage assessment. To reduce human skin damage due to pesticide formulations alternative safer anionic surfactants and polyoxyethylated nonionic surfactants should be incorporated.
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Investigating the biomechanics of a lizard skull using advanced computer modelling techniques with experimental validation
… about the original role of mesokinesis in squamate evolution.
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Adaptive evolution, sex-linkage, and gene conversion in the voltage-gated sodium channels of toxic newts and their snake predators
… across all nine sodium channel genes in squamate reptiles and show how historical changes have paved the way for full-body resistance in certain snakes. Finally, I use targeted sequence capture to obtain the sodium channel sequences of salamanders and show evidence that tetrodotoxin …
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Constraints on the Evolution of Viviparity in the Lizard Genus Sceloporus
… that viviparity would be constrained in some squamate lineages if maternal body temperatures are too high for successful embryonic development. I also evaluated the hypothesis that the evolutionary transition from oviparity to viviparity involves a "reduction" of the eggshell concurrent with …
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The Reproductive Cycle of Sceloporus undulatus From Alabama Corresponding Plasma Steroid Levels and Comments on Reproductive Variation.
… changes in this multi-clutched, oviparous squamate were examined. Plasma estrogen levels were slightly elevated during the luteal phases of the first two clutches and peaked during the last clutch. Plasma progesterone and testosterone were low and reached high levels during the last clutch. …
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Physiological and behavioral consequences of reptilian life in the slow lane: Ecology of beaded lizards and rattlesnakes.
… a standard metabolic rate only 40% that of other squamate reptiles of similar mass, and could fulfill its yearly maintenance energy requirements with a prey quantity equivalent to 0.93 x its body mass, which could be met with 2-3 large meals. After feeding, free-ranging rattlesnakes exhibited …
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Optimizing pharmacodynamics and evaluating echocardiographic effects of alfaxalone sedation in bearded dragons (Pogona vitticeps) and prairie rattlesnakes (Crotalus viridis)
… is an injectable sedative frequently utilized in squamate medicine. A novel formulation of alfaxalone was recently approved by the Food and Drug Administration for 28-day use after breaching the vial due to the addition of proprietary preservatives. Previous research performed in squamates focuses …
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Rise of present-day tetrapods in the paleotropics of Late Triassic equatorial Pangaea: new insights from microvertebrate data
… evidence for the Triassic acquisition in stem squamates and non-squamate lepidosaurs of dental features conserved in living squamates. The third chapter uses apomorphy-based identifications to describe the vertebrate diversity of the Thunderstorm Ridge site (PFV 456), providing evidence for the …
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Investigating the Patterns of Convergence in Pectoral Girdle Reduction During the Evolution of Limblessness in Lerista (Scincidae)
Over 30 tetrapod groups have evolved a snake-like, elongate, limbless body plan. Studies of the patterns of limb reduction have revealed a close relationship between the reduction of the limbs and body elongation; however, the loss of the skeletal elements that support the limb, the pectoral …
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Physiological and Ecological Constraints on the Evolution of Viviparity in Sceloporine Lizards
The purpose of this study was to evaluate putative physiological and ecological constraints on the evolution of viviparity in sceloporine lizards. In Chapters one and two, I investigated the role of in utero oxygen availability as a constraint on the capacity to support embryonic development during …
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Comparative Population Genomics and Speciation of Snakes Across the North American Deserts
<p>Understanding the process of speciation is of central interest to evolutionary biologists. Speciation can be studied using a phylogeographic approach, by identifying regions that promote lineage divergence, addressing whether speciation has occurred with gene flow, and when extended to multiple …