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 5 of 5 for “"gnathostomes"”.
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Glycoprotein hormone receptors in sea lamprey (Petromyzon marinus): Identification, characterization and implications for the evolution of the vertebrate hypothalamic-pituitary-gonadal/thyroid axes
… with the divergence of the jawed vertebrates (Gnathostomes) lineage from their jawless (Agnathan) ancestors. This coincides with the estimated time of divergence of the lamprey lineage, one of the two surviving Agnathan groups (lamprey and hagfishes) in the actual fauna. Therefore, the study of …
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Inner ear morphology in elasmobranchs: implications for auditory capacity and ecology
… their basal position in the evolutionary tree of gnathostomes, elasmobranchs can provide key insights into the early evolutionary history of the vertebrate nervous system. Sharks and their relatives were some of the first vertebrates to evolve the capacity for sound detection, and their auditory …
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Evolution of the structure and function of vertebrate brain gonadotropin-releasing hormone
… birds and higher reptiles, and Trp⁷,Leu⁸-GnRH in gnathostomes. His⁵,Trp⁷, Tyr⁸-GnRH appears to he present in numerous different vertebrates. Tyr³,Leu⁵,Glu⁶,Trp⁷,Lys⁸-GnRH has thus far only been detected in lamprey brain. A number of novel GnRHs, whose structures have not been elucidated are …
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Axial patterning of the chondrichthyan pharyngeal endoskeleton and the origin of the jaw
Classical comparative anatomical hypotheses propose that the upper and lower jaw evolved through modification of dorsal and ventral gill arch skeletal elements, respectively. These hypotheses were based largely on the skeletal anatomy of chondrichthyans (sharks, skates and holocephalans), but …
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The evolution and function of pharyngeal arch signalling centres in jawed vertebrates
Pharyngeal arches are paired columns of tissue that form when pouches of foregut endoderm contact surface ectoderm on either side of the embryonic vertebrate head. In fishes, endodermal pouches fuse with surface ectoderm to form gill slits. Once delineated, pharyngeal arches undergo morphogenesis …