Rare fossil of a horned dinosaur found from ’lost continent’

A rare fossil from eastern North America of a dog-sized horned dinosaur has been identified by Dr Nick Longrich. The fossil provides evidence of an east-west divide in North American dinosaur evolution. During the Late Cretaceous period, 66-100 million years ago, the land mass that is now North America was split in two continents by a shallow sea, the Western Interior Seaway, which ran from the Gulf of Mexico to the Arctic Ocean. Dinosaurs living in the western continent, called Laramidia, were similar to those found in Asia. However, few fossils of animals from the eastern 'lost continent' of Appalachia have been found because these areas being densely vegetated, making it difficult to discover and excavate fossils. Dr Longrich, from the Milner Centre for Evolution based in our Department of Biology & Biochemistry , studied one of these rare fossils, a fragment of a jaw bone kept in the Peabody Museum at Yale University. It turned out to be a member of the horned dinosaurs - the Ceratopsia.