A the Late Cretaceous reptile evolved to have resilient tooth enamel similar to that in mammals, Priosphenodon specimens from Argentina show.
Priosphenodon was a herbivore from the Late Cretaceous period that was about one meter long. Part of a group of reptiles called sphenodontians, these reptiles are unique in that they lost their ability to replace individual teeth. Instead, sphenodontians added new teeth to the back ends of their jaws as they grew.
“Priosphenodon has the strangest teeth I have personally ever seen,” says Aaron LeBlanc, a postdoctoral fellow in the department of biological sciences at the University of Alberta
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