CRETACEOUS NORTH AMERICAN DINOSAUR PALEOBIOGEOGRAPHIC PROVINCES REVISITED

The post Pangean world of the Cretaceous was a time of continued paleogeographic evolution. Tectonically, North America became connected to Eurasia via the Beringian land bridge allowing for the dispersal of dinosaurs between Asia and the Americas. Eustatically, the Late Cretaceous high stand united the interior continental seas of the Early Cretaceous and created two separate paleogeographic regions; Laramidia and Appalachia. Previous researchers have proposed dividing the North American continent into northern and southern paleobiogeographic provinces using Late Cretaceous dinosaur faunas. This project proposes to further subdivide the known paleobiogeographic provinces of Late Cretaceous dinosaurs in North America. With the development of new paleobiogeographic maps of Late Cretaceous (Campanian – Maastrichtian) dinosaur distributions, it has become apparent that North America may be further subdivided into four paleobiogeographic zones. The paleobiogeographic zones proposed are; the Northwest Laramidian, the Southwest Laramidian, the Northeast Appalachian and the Southeast Appalachian. These zones are largely established by dispersal barriers created by the Late Cretaceous high stand and the unique faunas that evolved within the separate Laramidian and Appalachian realms. A time slice series of Late Cretaceous paleobiogeographic maps will be presented that plot the distributions of dinosaurs from the Campanian to the Maastrichtian of North America. The new paleobiogeographic maps provide a framework for understanding dinosaur distributions and biogeographic provinciality during a time of continued paleogeographic change.