Hadrosaur Bonebed Crime Scene Investigation: Evolution, ecology and extinction of the last megaherbivores of the latest Cretaceous (FWOTM755)

Dinosaurs are not merely the iconic animals from your childhood. They represent excellent model organisms to understand macro-evolutionary and long term environmental processes. Non-avian dinosaurs (all dinosaurs except birds) disappeared during the Late Cretaceous extinction event. Hadrosaurs, such as Olorotitan and Parasaurolophus, were among the most abundant and successful Cretaceous dinosaurs, living alongside large carnivores such as Tarbosaurus and Tyrannosaurus. Hadrosaurs spread to all continents and reached sizes rivaling those of the giant sauropods. However, some hadrosaur groups disappear from the North American continent 5 to 6 million years before the extinction event, whereas the same groups thrived in Asia until the event. Understanding Late Cretaceous paleoecological changes and extinction requires insight into hadrosaur paleobiology. We have excellently preserved fossils, so that we can learn about tooth and bone growth by looking at their fossilized tissues under the microscope. We will sample the tissues of bones and teeth of Asian hadrosaurs, iguanodons (their Lower Cretaceous ancestors) and rhabdodontids (an evolutionary sister group). Studying these tissues, and their evolution throughout the Cretaceous will provide detailed information on growth, physiology, dietary specializations, interaction with changing environments and other ecological features of these enigmatic dinosaurs and furthermore provide clues about why some survived longer than others.

Keywords:Chemistry, dinosaurs, Paleoecology, Stable isotopes

Disciplines:Palaeo-ecology