sheep, common name for many species of wild and domesticated ruminant mammals of the genus Ovis of the Bovidae, or cattle, family. The male is called a ram (if castrated it is a wether), the female is called a ewe, and their offspring is a lamb. Wild sheep, found in mountainous parts of Asia, North America, and the Mediterranean region, are agile rock climbers with large, spiraling horns. They do not bear wool. Among those species are the Asian argali, the Barbary sheep, or aoudad, of North Africa, and the North American bighorn, or Rocky Mountain sheep, found from Alaska to Mexico. Sheep were first domesticated c.7,000 years ago, and the first use of their fleeces for wool is dated at c.4000 b.c. Descendants of Roman flocks figured in the evolution of the Merino type in Spain. The present-day breeds of domesticated sheep—which vary greatly because they were developed for different purposes and environments—are all thought to be derived chiefly from the wild mouflon of Sardinia and Corsica and from the urial of Asia. Sheep are bred for their wool, meat (mutton or lamb, according to age), skins, and, in certain parts of Europe and the Middle East, their milk, from which cheese is made. They are found mostly in temperate climates and thrive on roughages. Most sheep mate in the fall, and the lambs, born five months later, are called spring lambs. Among the important breeds are the Columbia, Cotswold, Dorset, Hampshire, Karakul, Leicester, Lincoln, Merino, Oxford, Rambouillet, Shropshire, Southdown, and Suffolk sheep. Sheep are classified in the phylum Chordata, subphylum Vertebrata, class Mammalia, order Artiodactyla, family Bovidae.