‘We were able to show that the first tusks belonged to animals that came before modern mammals, called dicynodonts,’ said Kenneth Angielczyk, co-author and curator at Chicago’s Field Museum. ‘They’re very weird animals.’Dicynodonts, though not mammals, are distant relatives and are more closely related to mammals than dinosaurs and other reptiles. Dicynodonts lived between 270-201 million years ago and included a diverse range of animals from tiny rat-like dicynodonts to huge elephant-sized dicynodonts. They are known for having a very peculiar arrangement of teeth. A defining feature of these animals, first discovered 176 years ago, is the protruding tusks in their upper jaws. Most had two upper tusks that came down from the canine position, but they rarely had additional teeth. Instead, dicynodonts had a beak at the front of their mouths that was made of keratin and resembled a turtles beak.