Dental exams conducted on fossils from more than 200 million years ago suggest that the earliest true tusks were sported by breeds of weird-looking creatures known as dicynodonts.
The evidence, laid out today in the Proceedings of the Royal Society B, could shed light on how species ranging from elephants and walruses to warthogs and rabbit-like hyraxes came to have tusks.
“Tusks have evolved a number of times, which makes you wonder how — and why?” study co-author Christian Sidor, a biology professor at the University of Washington and a curator at UW’s Burke Museum of Natural History and Culture, said in a news release. “We now have good data on the anatomical changes that needed to happen for dicynodonts to evolve tusks. For other groups, like warthogs or walruses, the jury is still out.”