Horse Evolution

Pilohippus

5

Pliohippus is the bad apple on the equine evolutionary tree. It had deep impressions in its skull, not seen in any other equid genus, and its teeth were curved rather than straight.

Merychippus

15

Merychippus is the first known horse to have grazed exclusively on grass, and it adapted to its North American habitat.

Mesohippus

40

This horse balanced itself mainly on its enlarged middle toes.

Hyracotherium

56

It had four-hoofed toes on each front foot and three-hoofed toes on each hind foot. Each toe had a pad on its underside, similar to those of a dog.