This is a skull of an oreodont, an extinct herbivous North American artidactyis (even toed ungulates). It lived in a savanna like enviroment in the Middle Eocene to the end of the Miocene Period some 40 million years age. There are no close relatives living today; camels and pigs would be the nearest. This specimen is from the Brule Formation of the White River Badlands, South Dakota. USA. and such fossils have only been found in North America.