The former is by far larger of the two groups, with over a hundred living species, including such familiar animals as sheep, goats, camels, pigs, cows, deer, and antelopes. In the early Cenozoic , perissodactyls were much more diverse, including the great extinct brontotheres and Indricotherium , the largest land mammal of all time.
Many hoofed mammals live in grasslands and savannahs.
Ungulates have evolved features that are adaptive for life on open grasslands , in particular long legs to increase running speed. The hoof of a horse or cow is anatomically an enlarged toe. The remaining toes not used for walking are either reduced, as in pigs and tapirs, or completely lost, as in rhinos and most ruminants. Many ungulates have also evolved large, complexly grooved molar teeth to grind their food of grasses and other plants. Visit DeerNet for information on conservation of wild ungulates and their kin.