2012 KITZMILLER LECTURE The Ohio Center for Ecology & Evolutionary Biology Presents…. Dr. Jacques Gauthier Professor, Geology & Geophysics & Curator, Yale Peabody Museum of Natural History THURSDAY APRIL 26th Noon BAKER BALLROOM “Not Your Parents’ Dinosaurs: The Role of Crown Dinosaurs and Stem-Birds in Evolutionary Theory” Did you know that tyrannosaurs had feathers? New fossils have dramatically altered our understanding of dinosaur evolution. In a triumph for the predictive power of the Darwin’s ‘Theory of Descent’, they provide more support of the idea that birds are in fact living (crown) dinosaurs. But this also means that other species such as Diplodocus and Triceratops are in fact early (stem) birds. This may not seem intuitive, as those extinct giants are so different from one another and from the diminutive hummingbirds of today. However, our job as evolutionists should be less concerned with similarity and more focused on discovering common-ancestry relationships. And on that point there can be no doubt: dinosaurs share a deep genealogical connection with birds. Although this hypothesis has been the simplest explanation for the available data from the midnineteenth century to the present day, it continues to meet resistance. The history of this controversy can teach us some profound lessons about the scientific enterprise, not the least of which is that although science as a process may be objective, people are scientists, and they sometimes aren’t.