A study published in the journal ‘Cretaceous Research’ reveals that scientists have unearthed a rare fossil of a dog–sized horned dinosaur in eastern North America. The fossil provides an evidence of the east–west divide in the North American dinosaur evolution.
The fossil belonged to a dinosaur which wandered about the earth around 100 million years ago during the late Cretaceous period. During that time, the landmass of North America was divided into two continents by a shallow sea known as the Western Interior Sea that ran between the Gulf of Mexico and the Arctic Ocean. Dinosaurs that lived in Laramidia or the western continent were similar to those found in Asia. However, little progress has been made about the dinosaurs living in the eastern continent or Appalachia. As this eastern continent is densely vegetated, it becomes difficult to excavate fossils here.
Dr. Nick Longrich from the University of Bath in UK identified the fossil as a member of the Ceratopsia family. Ceratopsia is a group of herbivorous, horned dinosaurs that lived during the Cretaceous period. The jaw of the dinosaur is more slender than that of the Ceratopsia dinosaurs found in the western continent. Hence, this leads to the conclusion that dinosaurs in the eastern continent had a different diet compared to their western counterparts.