In North America 67 million years ago, the Earth was wet and swampy. Tyrannosaurus, ankylosaurs and triceratops lived there, but also some primitive mammals and the first flowering plants. It would take tens of millions of years before the Americas touched each other. And the area now called Wyoming was coastal in the Late Cretaceous.
The fact that the paleontologists from Naturalis unearthed a Triceratops here in 2013 is therefore not in itself that special. What makes the find unique is that there were five of them: drowned at the same time in the same place in a prehistoric swamp.
Triceratops was a herd animal
Paleontologist Jimmy de Rooij received his PhD last Wednesday for his research into the five dinosaurs. His analysis of the 1,200 fossil bones confirms for the first time what scientists have suspected for a long time: the herbivorous triceratops lived in herds. In fact, research into the physicochemical properties of the teeth of the five animals points to an itinerant existence – an existence that was the same for all five triceratopses.
In addition to the chemical composition of the tooth enamel, De Rooij examined the grain size of the earth at the site and studied the fossil bones of the dinosaurs under the microscope. For example, he discovered that all five triceratopses had a slow growth pattern. Another indication that they grew up under similar circumstances.
Down together
Five dinosaurs – each no older than 28 years old – passing through the swamps of Laramidia. Perhaps they were looking for new habitat or food, or they were tired and hungry after a long journey. Maybe it was one T. rex which drove them deeper into the swamp, with all its consequences.
What we know for sure is that they went down together. ‘And that of course raises all new questions,’ says De Rooij in a press release. Further research must reveal exactly how complex the social behavior of the triceratops was.
Merav Pront is a digital editor at National Geographic and also regularly writes for the magazine. During her studies in human geography, she learned to place local phenomena in an international context. As a freelance journalist, she looks for the small stories behind the big news. She writes for the VPRO and the National Holocaust Museum, among others.
Tags: Dutch paleontologist discovers triceratops herd animal
