(Mirror Daily, United States) – While exploring the collection at the Peabody Museum, a scientist found a fossil of a rare horned dinosaur that lived around 77 million years ago in North America. More importantly, the species was apparently used to roaming the more mysterious eastern part of today’s continent. Back then, however, it was the ‘lost continent’, isolated from the world.
Dr. Nick Longrich found evidence of the division between western and eastern North America during the Late Cretaceous period, between 66 to 100 million years ago. He found a jaw within the collection of fossils that was discovered around 30 years ago, and conducted further investigation. Initially labeled as a ‘duckbilled dinosaur’, the scientist believed it was in fact, part of an entirely different species.
The fossil belonged to a Leptoceratopsid, a dog-sized horned dinosaur. It was cousin of the famous Triceratops, as part of the Ceratopsids family. The species had the trademark frill on the back of their skull like the Triceratops, and two horns on the sides of its cheeks. They were widely spread around the Late Cretaceous period.
However, Dr. Longrich found that this particular specimen had a more slender jaw, a sign of a diet on soft plants. The teeth had an unusual pattern, with the jaw bending up and down, which was not like any other dinosaur found. This led to the conclusion that the new Leptoceratopsid wasn’t like any other of its species found in the west. And, it likely belonged to the east where vegetation was far more dense.
Around 200 million years ago, all the continents were placed together in what was called Pangeea. Approximately 100 million years later, the separation reached its peak, with high sea levels, and ultimately the continents we have today. North America, as we know it now, was split into two by the Western Interior Seaway. This mass of water stretched from the Gulf of Mexico to the Arctic Ocean.
It split it into two different continents, specifically Laramidia in the west, and Appalachia in the east. Laramidia was connected to Asia on its northernmost point, which explains why dinosaurs species found in western North America and Asia look alike. However, Appalachia was entirely isolated. It allowed the continent to see to its own evolutionary path, as the dinosaurs had no way of reaching each other.
This adds to the theory the two land masses were separated by a vast body of water. The new species of Leptoceratopsid belonged to the more mysterious Appalachia. The separation led to the dinosaurs evolving in an entirely different direction, which means that there are many more species out there undiscovered that would look odd when compared to those we do know.
Image source: phys.org