According to a new study published in the journal Science Advances, a 9-meter-long three-horned dinosaur called the Triceratops developed teeth that could finely slice through dense material giving the dinosaur a richer and more varied diet than modern-day reptiles.
Dental tissue evolution in Ceratopsia, a group of plant-eating dinosaurs that thrived in what are now North America, Europe, and Asia, during Cretaceous. Image credit: Gregory M. Erickson et al.
Today, reptilian teeth are constructed in such a way that they are used mostly for seizing food – whether plant or animal – and then crushing it. The teeth do not occlude like those of mammals. In essence they can’t chew. The teeth of most herbivorous mammals self wear with use to create complex file surfaces for mincing plants.
“It’s just been assumed that dinosaurs didn’t do things like mammals, but in some ways, they’re actually more complex,” said Prof Gregory Erickson of Florida State University, lead author on the study.
Prof Erickson and his colleagues from the University of Pennsylvania, Lehigh University, American Museum of Natural History and the University of Florida, examined the teeth of Triceratops from museum specimens collected around North America.
They discovered that the teeth were made of five layers of tissue. In contrast, plant-eating horse and bison teeth, once considered the most complex ever to evolve, have four layers of tissue. Crocodiles and other reptiles have just two.
“Each of those tissues does something. They’re not just there for looks,” Prof Erickson explained.
“We show how Triceratops and its relatives evolved teeth that wore during feeding to create fullers (recessed central regions on cutting blades) on the chewing surfaces,” the scientists wrote in the paper.
“This unique morphology served to reduce friction during feeding. It was achieved through the evolution of a complex suite of osseous dental tissues rivaling the complexity of mammalian dentitions.”
The question that remains is how prevalent complex dental structure was among dinosaurs and other reptiles.
The paleontologists intend to explore this further by examining other reptilian dental records and structures.
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Gregory M. Erickson et al. 2015. Wear biomechanics in the slicing dentition of the giant horned dinosaur Triceratops. Science Advances, vol. 1, no. 5, e1500055; doi: 10.1126/sciadv.1500055
