Uintatherium is an extinct megafauna mammal which lived approximately 45 to 40 million years ago during the Middle Eocene Period. It was first discovered during the excavation of Fort Bridger in Wyoming during the early 1870s. In 1872, it was given the name by Uintatherium Joseph Leidy – a name which means “Beast of the Uinta Mountains.”
If you look closely at Uintatherium pictures, then you might think that this animal was a cross between a dinosaur, a hippopotamus, and a rhinoceros. However, it really was a herbivorous mammal that roamed the plains of North America. They were not the smartest animals alive, in fact, their brains were relatively small compared to their enormous bodies. Its brain size was probably small due to it not having to hunt for its food and not having any natural predators.
A full-size Uintatherium would have been about 13 feet long and about 2 tons. This would have made it virtually immune to predation. It was just too large to have been the target of any of the carnivores that were alive at the time. On top of its head was 3 pairs of knobby horns. These were probably used as a way to attract females during mating season.
One of the most fascinating facts about Uintatherium is how they managed to avoid extinction for so long. It didn’t have any of the attributes you would expect to find in species that were successful in survival. Eventually, they did go extinct and they did it in a rather sudden fashion. Scientists still aren’t sure what mad them die out so quickly. Some scientists have speculated that arrival of large brontotheres such as Meacerops massively out-competed Uintatherium for access to food and that is why it suddenly went extinct.