PLIOHIPPUS

The First Horses
Pliohippus

12 - 6 Million Years Ago
Fossils of Pliohippus are found at many late Miocene localities in Colorado, Nebraska, the Dakotas and Canada. Species in this genus lived from 12-6 million years ago. In the late Miocene Epoch, one branch of horses crossed into Asia and quickly multiplied and spread to Europe. Meanwhile in North America, the horse developed into the final model. Pliohippus was the first true monodactyl (one-toed animal) of evolutionary history. Pliohippus had increasing need for speed to outrun its enemies, so the hoof evolved from the continued over-development of its middle toe. Its denture and extremities were the nearest approach to our present-day horses. This horse now spread into South America, as well as Asia, Europe, and Africa. In the last two million years, Equus emerged as the large, magnificent creature we admire today. Finally about 8,000 years ago, Equus became extinct in the New World and was not to return until the Spanish brought horses to the Western Hemisphere in the 1,400's.