New research suggests dinosaurs like Tyrannosaurus rex and other carnivorous theropods are heavily indebted to a unique serrated tooth structure that enabled their hunting prowess.
Imaging analysis of theropod teeth reveal a penetrating saw-like structure that allowed T. rex and Allosaurus, as well as earlier theropods like Coelophysis, to slash through thick animal skin and bone.
Researchers at the University of Toronto Mississauga were able to gain unique insights into the internal structure of theropod teeth by imaging tooth slices expertly cut from fossilized teeth. Their work -- which was made possible by scanning electron microscopy and other imaging and chemical analysis technologies -- proved the dinos' tooth structure enabled their abilities, and was not simply the byproduct of chewing hard materials.
"What is so fascinating to me is that all animal teeth are made from the same building blocks, but the way the blocks fit together to form the structure of the tooth greatly affects how that animal processes food," Kirstin Brink, a post-doctoral researcher in the school's biology department, said in a press release. "The hidden complexity of the tooth structure in theropods suggests that they were more efficient at handling prey than previously thought, likely contributing to their success."
Though the teeth of other extinct animals resemble the choppers inside the mouths of fossilized carnivorous theropods, the latest research suggests this likeness is superficial. Only carnivorous theropods possessed the internally penetrating serration that was key to their deadly bite.
"This adaptation may have played an important role in the initial radiation and subsequent success of theropods as terrestrial apex predators," researchers wrote in their new study, published this week in the journal Scientific Reports.
The Komodo dragon, native to Indonesia, is the only reptile living today with teeth that boast internal serration. It, too, takes down impressively large prey.