Hoof

Hoof, enlarged, heavy toenail developed by many herbivorous animals. Since speed is a large herbivore's best defense against a predator, it is an advantage to be able to run on the tips of the toes, as this adds length to the stride. Hooves give stability to this tiptoe stance. Animals with hooves include horses, rhinoceroses, antelopes, goats, sheep, hogs, hippopotamuses, camels, and cattle.