Many animals have tusks, from elephants to walruses to hyraxes. But one thing tusked animals have in common is that they鈥檙e all mammals 鈥� no known fish, reptiles or birds have them. But that was not always the case. In a study published Oct. 27 in the Proceedings of the Royal Society B, a team of paleontologists at Harvard University, the Field Museum, the 天美影视传媒 and Idaho State University traced the first tusks back to dicynodonts 鈥� ancient mammal relatives that lived before the dinosaurs.










