Wikipedia
Merychippus
Merychippus is an extinct proto- horse of the family Equidae that was endemic to North America during the Miocene from 20.43—10.3 Ma living for approximately .
It had three toes on each foot and is the first horse known to have grazed. Its name means " ruminant horse", but current evidence does not support Merychippus ruminating.
Usage examples of "merychippus".
Had not merychippus developed these self-renewing grinders, the horse as we know it could have neither developed nor survived.
But what gained greatest attention, especially from ranchers in the west, was his discovery in subsequent years of handsome skeletons of four of the progenitors of the horse: eohippus, mesohippus, miohippus and the crucial, determinative merychippus.