The oreodonts were the dominant herbivores, and the primary prey animal, of the Oligocene in North America. Superficially oreodonts look more like carnivores than herbivores. For example, they have four toes on the front legs and five toes on the back with claw‑like hooves. Their robust snout begins with sharp, caniniform teeth (the lower first premolar sharpened against the upper canine). Their cheek teeth are crescentic, like a deer’s, so there is no doubt that they are strictly leaf eaters. There is debate on whether their closest relatives are camels or pigs, but it is likely that oreodonts ruminated (chewed their cud) like camels, deer, and cows.