The mountain goat, Oreamnos Americanus, in the family Bovidae, is not a true goat (Capra) but rather a member of a group (tribe Rupricaprini) known as goat antelopes. Mountain goats stand about 1 m (39 in) high at the shoulder and weigh up to 140 kg (300 lb). The goat is white sometimes tinged with yellow, with a thick, woolly underfur. The hair above the shoulder and on the neck is long and stiff. Both sexes have beards and permanent, black, unbranched horns that seldom exceed 23 cm (9 in) long. The hooves are hard and sharp and surround soft pads, enabling the animals to obtain footing on ice and rocks. Mountain goats are found from southwestern
Mountain sheep are members of the genus Ovis in the family Bovidae and are characterized by narrow muzzle, pointed ears, and massive curling horns in the older males (rams). Unlike true goats, Capra, they lack beards and have dished, or concave, foreheads. The largest of the mountain sheep, the argaili, reaches 1.2 m (4 ft) in height at the shoulder and 160 kg (350 lb) in weight. Coat colors range from white to gray or dark brawn. The coat is generally short and coarse, with only the mouflon species developing a woolly undercoat in winter. Some forms have a mane of hair down the front of the neck. Mountain sheep generally inhabit dry upland areas, from craggy mountains into semideserts. During the summer moths the adult males live in groups apart from the females and their young. In late fall and early winter the males battle for possession of females, which they gather into harems of up to 12 awes. Gestation lasts 5 to 6 months, and form one to three lambs are born in the spring.
Mountain sheep are usually classified into six species; the bighorn, O. Canadensis, of the western United States and southwestern Canada; the Dall sheep, O. dalli, of Alaska and northwestern Canada; the argali, or Marco Polo sheep, O. ammon, of central Asia; the red sheep, O. laristanica, of southern Iran; and the mouflon, O. musimon, of Sardinia and Corsica.