Hoof

A horse has only one toe per foot. Of the original five, only the middle toe became massively enlarged while the rest shrank away. What we call a "hoof" is actually the nail of that single giant toe.

Newborn horses don't have hard hooves. A jelly-like covering called "foal slippers" wraps around their hooves, protecting the mother during pregnancy and birth. These coverings naturally fall off once the foal begins to stand and walk.