Document Details

Document Type:   Thesis
Title:   A Virtual Phytosaur Endocast and its Implications for Sensory System Evolution in Archosaurs
Author:   Waymon Holloway
College:   Science
Degree Program:   Biological Sciences, M.S.
Degree:   Master of Science
Committee Director:   F. Robin O'Keefe
Document Availability:   Document available for World-Wide access.
Date of Defense:   June 2011

Due to the overall morphological similarities between the Triassic archosaurs of the order Phytosauria and extant crocodilians, most studies have assumed that the two shared similar lifestyles. Many studies involving phytosaurs have focused on the external cranial morphology of various taxa. Internal cranial anatomy has received relatively little attention. As a result, comparative morphology studies of the braincases interior, or endocast, of phytosaurs are an area of potential exploration. Just as modern medical Xray computed tomography (CT) can be used to create three-dimensional images of internal structures of living subjects, such technology offers a non-invasive means of studying the internal anatomy of fossil specimens. CT scan data, used to virtually model and analyze the endocast of a phytosaur specimen, reveals an endocast morphology conserved among phytosaurs, crocodilians, and other Crurotarsi. This conservatism persists in taxa with numerous synapomorphies and distinctive ecologies, unlike the endocast specialization seen in other archosaurs like Dinosauria. 

Download Document:   holloway-waymon-2011-ms.pdf