Pliohippus

Pliohippus leidyanus
The drawing shown at the top is a reconstruction of what scientists believe a horse may have looked like at a later stage of its evolution. This drawing illustrates Pliohippus, the first of the one-toed horses, from the Pliocene Epoch. The drawing shown at the bottom is a reconstruction of its skeleton and foot bones.
The drawing shown at the top is a reconstruction of what scientists believe a horse may have looked like at a later stage of its evolution. This drawing illustrates Pliohippus, the first of the one-toed horses, from the Pliocene Epoch. The drawing shown at the bottom is a reconstruction of its skeleton and foot bones.

Pliohippus, extinct genus of horses that inhabited North America during the Pliocene Epoch (5.3–2.6 million years ago). Pliohippus, the earliest one-toed horse, evolved from Merychippus, a three-toed horse of the preceding Miocene Epoch (23–5.3 million years ago). The teeth of Pliohippus are taller and more complexly folded than those of earlier horses; these features indicate a greater dependence on grazing than browsing for food. Because of its diet and its specializations for running, it is likely that Pliohippus lived on open plains.

This article was most recently revised and updated by Richard Pallardy.
Citation Information
Article Title: Pliohippus
Website Name: Encyclopaedia Britannica
Publisher: Encyclopaedia Britannica, Inc.
Date Published: 15 December 2010
Access Date: November 13, 2026