Tyrannosaurus rex and other large meat-loving dinosaurs had deeply serrated teeth that let them tear through the flesh and bone of victims.
Only one animal living today has this same tooth structure, according to new research, published in the journal Scientific Reports. The Komodo dragon, which is the world’s largest lizard, holds that distinction.
“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,” project leader Kirstin Brink of the University of Toronto Mississauga’s Department of Biology, said in a media release.
Brink and her colleagues used both a scanning electron microscope and a synchrotron, which can identify a substance’s chemical composition, to analyse tooth slices from eight meat-eating dinosaurs, such as T. rex, Allosaurus, Coelophysis and Gorgosaurus.
The investigations revealed that the serrations on the teeth of these bloodthirsty predators were supported by tissues inside of each tooth. The arrangement of these tissues reinforced the serrations all the more, making the teeth more efficient at biting through bones and ripping flesh.
As a result, it was a dinosaur-eat-dinosaur world, since the strong teeth and other adaptations allowed these now-extinct animals to take down very large prey. Before carnivorous dinosaurs died out (dinosaurs that were not birds, that is), they prospered for about 165 million years as the planet’s top terrestrial predators.
Komodo dragons, which are native to Indonesia, can kill large prey too, including humans and water buffalos. Komodo dragons also produce a venom that can prevent their victim’s blood from clotting. Before the venom was discovered by scientists, animal experts used to think that bacteria harboured in the mouths of Komodo dragons helped to kill prey.
Brink and her team determined that, in the dinosaur teeth, the unique arrangement of interior tooth tissues did not develop in response to the carnivores chewing hard materials. They came to that conclusion after examining samples of dinosaur teeth that had not yet broken through the gums when the animals died. They also looked at samples from mature dinosaur teeth.