Tyrannosaur phylogeny and biology: new research on ancient model organisms
Tuesday September 21st
Room 417 Schermerhorn Hall
Summary: Tyrannosaurus is the most feared and familiar of all of the dinosaurs, but recent fossil discoveries give a startling new picture of tyrannosaur evolution. Five important new species have been revealed over the past year, running the gamut from some of the most primitive and smallest members of the group to completely bizarre forms. Raptorex is barely larger than a man but has all of the classic tyrannosaur features, such as the large skull and puny arms, indicating that the tyrannosaur body plan first evolved at small size and not in giant bone-crunchers. Alioramus, from the Late Cretaceous of Mongolia, is one of the closest cousins of Tyrannosaurus but is only half its size and has a bizarre long snout and eight horns on its skull. Sinotyrannus is one of the oldest tyrannosaurs, but was nearly the size of T. rex itself! These, and other discoveries, are overturning previous theories about tyrannosaur evolution. The tyrannosaur group was a long-lived lineage that began with small species in the Middle Jurassic. For the first 80 million years of their history tyrannosaurs remained small animals, until rapidly developing colossal size at the end of the Cretaceous. I have studied many of these specimens and will discuss the latest views on tyrannosaur evolution and biology, using as a guide a newly-published phylogenetic analysis (family tree) that is a major part of my dissertation research.
Stephen Brusatte, a Ph.D. student in the department of Earth and Environmental Sciences, is based at the American Museum of Natural History. His research focuses on the anatomy, systematics, phylogeny, and macroevolution of archosaurian reptiles, especially carnivorous dinosaurs. His doctoral work concerns the phylogeny of basal coelurosaurian theropods, some of the closest relatives to living birds, and large-scale patterns of morphological evolution in the carnivorous dinosaurs across the Mesozoic. Steve has active fieldwork projects in the Triassic of Portugal, Poland, and Lithuania, and is building a fieldwork collaboration in the Paleocene of New Mexico. He is also the author of three books on dinosaurs for amateur paleontology audiences.
Steve received a B.S. in Geohysical Sciences in 2006 from the University of Chicago and two Masters of Science (in Paleobiology and Earth Sciences) from the University of Bristol in 2008.
Future talks are scheduled for Tuesdays from 12:15-1:00pm in Room 417 Schermerhorn Hall. Attendees are welcome to bring their lunch.
All are welcome to attend!