Although the two giant species appear similar, both species had key differences. While "Arctodus simus" inhabited most of North America for over a million years, "Arctotherium angustidens" has only been found in the Southern Cone, from open plains habitat. Also, while "Arctodus simus" varied its diet between mostly eating meat in Alaska to omnivory elsewhere, "Arctotherium angustidens" had similar rates of eating meat across specimens, according to studies of its bone chemistry.