In children’s books and cartoons, crocodiles and their kin tend to have an impressive array of identical teeth, each shaped like a sharp, pointed weapon primed for tearing through flesh. In reality, there is often a bit more variation, says paleontologist Keegan Melstrom of the University of Utah.

“But that is nothing compared to the staggering diversity in the teeth of extinct crocodile-like reptiles, or Crocodyliformes,” he says. “Some of those extinct crocs had really weird teeth.”

Now, an analysis of 146 fossilized teeth belonging to 16 extinct crocodile relatives has revealed something surprising: At least three times in their history, ancient croc cousins became vegetarians.

“This shows that this was a succesful dietary strategy,” says Melstrom, whose team presents