Oliver Wings

Academic paper

Dissertation zur Erlangung des Doktorgrades (Dr. rer. nat.) der Mathematisch-Naturwissenschaftlichen Fakultät der Rheinischen Friedrich-Wilhelms-Universität Bonn

PREFACE Despite of hundreds of papers and more than 150 years of research, the problems of gastrolith function and identification in the fossil record are far from being solved. Therefore, this dissertation project was conceived and a broad approach with consideration of many geological and biological factors was envisaged. The restricted timeframe of a dissertation did not allow the comprehensive study of the numerous fossil species from different clades with gastroliths. Consequently, I decided to concentrate on dinosaurs, with a focus on sauropodomorphs, an especially interesting clade because of their gigantism and their physiological adaptations. Since an examination of fossil gastroliths alone would have left too many uncertainties, modern gastroliths from several vertebrate clades were included in this study. Because the function of gastroliths is best researched in birds and the closest modern equivalent to gastroliths-bearing dinosaurs are ratites, I focused on ostriches. I did not focus on aquatic lithophagic clades such as plesiosaurs, pinnipeds, and crocodilians. However, since gastroliths in these groups offer new insights into avian and dinosaurian gastroliths, basic facts about gastroliths in aquatic animals are included where appropriate.

English