Dissertation Research: Anatomy, Evolution, and Functional Significance of Cephalic Vasculature in Archosauria, with Special Emphasis on Birds, Crocodilians, and Nonavian Dinosaurs

Ohio University, Athens OH

Investigators

Abstract

This study will examine the circulatory system of the head in extinct (dinosaurs) and living (birds and crocodilians) members of the Archosauria. The research holds significance beyond basic anatomy in that the inference of vascular "devices" will shed light on the behavior and physiology of extinct organisms. For example, warm-blooded vertebrates have countercurrent heat exchangers in their cephalic circulatory system, which heat or cool important structures in the head such as the brain. The major objectives of the research are (1) to document the anatomy of the head vessels in birds and crocodilians, (2) reconstruct vascular structures in extinct archosaurs (e.g., dinosaurs), (3) examine the evolution of the vascular system, and (4) formulate hypotheses on functional/physiological significance of vascular arrangements. Data on birds and crocodilians will be obtained via gross anatomy, histology, and a novel X-ray technique. Data on dinosaurs will be attained by identifying vascular traces in fossils. This project will be the first to compare head vasculature in crocodilians, birds, and other vertebrates, and to reconstruct vascular structures and patterns in extinct archosaurs.