Pronghorn are the fastest animals in the Western Hemisphere.
They are the only surviving members of a group of animals that has been evolving in North America for the last 20 million years. They have horns rather than antlers and their horns are unique in that they have prongs and they are shed and regrown each year. Most horned animals never shed their horns. Pronghorn are not very closely related to the antelope of Africa but were described as being similar in appearance to the African antelope and gazelle by the explorers Lewis and Clark. They are therefore often called Pronghorn Antelope rather than just Pronghorn.