PhD Defense - Thomas Arbez

La soutenance de thèse de Thomas Arbez aura lieu le Mardi 6 novembre à 14h à l’amphithéâtre d’Anatomie comparée et de Paléontologie.
Thèse de doctorat sous la direction de Jean-Sébastien Steyer et de Gaël Clément
Composition du jury :
Abstract:
The intracranial anatomy of the stegocephals Stanocephalosaurus (Temnospondyli), Laosuchus (Chroniosuchia) and Diplocaulus (Lepospondyli) has been revealed by X-rays tomography and allowed to better understand their paleobiology: 1) the middle ear of Stanocephalosaurus would be an underwater adapted hearing system; 2) intraosseous sensorial canals have been identified in Laosuchus. The endocranial morphology have been included in a phylogenetic analysis on the debated relationships between stegocephals and lissamphibians. This analysis shows that the monophyly of Lissamphibia may result from a long-branch attraction, due to the optimisation of the cranial simplification, here as identified convergent. The morphologies of braincase, stapes and palate favour a biphyletic origin of lissamphibians among temnospondyls.