PhD Title: Endocranial microtomographic study of marine Sauropsida (Plesiosauria and Mosasauroidea) from the Turonian (Late Cretaceous) of Morocco: palaeobiological and behavioral implications.

Subject:  The recent development of non-invasive, three-dimensional, highresolution methods of analysis (microtomography) constitutes a major innovation for the biological and behavioral analysis of extinct species. It allows the acquisition of detailed anatomical or microanatomical endocranium data (relative to the brain, inner ear, nerves, etc.) previously accessible only through destructive methods (thin sections) or sketchy natural endocranial casts. While many microtomographic studies are now available concerning the neuroanatomy of living and fossil Archosauromorphes (e.g., crocodiles, avian and non-avian dinosaurs), the few recent neuroanatomical studies available for Mesozoic marine reptiles remain focused on very specific parts of the endocast, thus offering only a partial view of its anatomy. It is only very recently that a more extensive analysis was performed, on a group of Jurassic sea-turtles. Currently, there is therefore no global comparative study of endocranial anatomy for several iconic top-predator Mesozoic marine reptiles, which limits our understanding of their sensorial and behavioral adaptations associated to their return to an aquatic lifestyle. The goal of this project is a detailed comparative study (including the analysis of some extant forms), combining classical anatomy with high-resolution microtomography, of the endocranium of two major Mesozoic marine reptile clades: the Mosasauroidea (Squamata) and the Plesiosauria (Sauropterygia).

Supervisors: Dr. Nathalie BARDET, Dr. Peggy VINCENT & Dr. Alexandra HOUSSAYE