Science, Tech, Math › Animals & Nature Merychippus Share Flipboard Email Print Merychippus (Wikimedia Commons). Animals & Nature Dinosaurs Prehistoric Mammals Basics Paleontologists Carnivores Dinosaurs & Birds Herbivores Marine Reptiles Amphibians Birds Habitat Profiles Mammals Reptiles Wildlife Conservation Insects Marine Life Forestry Evolution View More By Bob Strauss Science Writer B.S., Cornell University Bob Strauss is a science writer and the author of several books, including "The Big Book of What, How and Why" and "A Field Guide to the Dinosaurs of North America." our editorial process Bob Strauss Updated May 04, 2019 Name: Merychippus (Greek for "ruminant horse"); pronounced MEH-ree-CHIP-us Habitat: Plains of North America Historical Epoch: Late Miocene (17-10 million years ago) Size and Weight: About three feet tall at the shoulder and up to 500 pounds Diet: Plants Distinguishing Characteristics: Large size; recognizably horse-like head; teeth adapted to grazing; vestigial side toes on front and hind feet About Merychippus Merychippus was something of a watershed in equine evolution: this was the first prehistoric horse to bear a marked resemblance to modern horses, although it was slightly bigger (up to three feet high at the shoulder and 500 pounds) and still possessed vestigial toes on either side of its feet (these toes didn't reach all the way to the ground, though, so Merychippus still would have run in a recognizably horselike way). By the way, the name of this genus, Greek for "ruminant horse," is a bit of a mistake; true ruminants have extra stomachs and chew cuds, like cows, and Merychippus was in fact the first true grazing horse, subsisting on the widespread grasses of its North American habitat. The end of the Miocene epoch, about 10 million years ago, marked what paleontologists call the "Merychippine radiation": various populations of Merychippus spawned about 20 separate species of late Cenozoic horses, distributed across various genera, including Hipparion, Hippidion and Protohippus, all of these ultimately leading to the modern horse genus Equus. As such, Merychippus probably deserves to be better known than it is today, rather than being considered just one of the innumerable "-hippus" genera that populated late Cenozoic North America!