[1] Only one species, the pronghorn (Antilocapra americana), is living today; all other members of the family are extinct.
They have a complex, four-chambered stomach for digesting tough plant matter, cloven hooves, and small, forked horns.
Their horns resemble those of the bovids, in that they have a true horny sheath, but, uniquely, they are shed outside the breeding season, and subsequently regrown.
[2] Tragulidae Antilocapridae Giraffidae Cervidae Bovidae Moschidae The ancestors of pronghorn diverged from the giraffids in the Early Miocene.
[2] This was in part of a relatively late mammal diversification following a climate change that transformed subtropical woodlands into open savannah grasslands.