Ovis

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This article refers to the sheep genus. For the species commonly referred to simply as "sheep", see Domestic sheep.

Sheep

Scientific classification

Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Artiodactyla
Family:	Bovidae
Subfamily:	Caprinae
Genus:	Ovis Linnaeus, 1758

Species

See text.

A sheep is an individual of any of the eight woolly mammal species that comprise the genus Ovis, part of the goat antelope subfamily. All the sheep are bovids (members of the family Bovidae) and ruminants, meaning they chew cud. The domestic sheep is thought to be descended from the wild moufflon of central and southwest Asia. Members of the genus are highly gregarious.

Female sheep are called ewes, males are called rams (sometimes also called "bucks" or "tups") and young sheep are called lambs. The adjective applying to sheep is ovine and the collective terms for sheep are flock and mob. The term herd is also occasionally used in this sense.

Sheep are usually stockier than other bovines and some have horns which are more divergent than those of goats. Sheep have scent glands on the face and hind feet. Communication through the scent glands is not well understood but is thought to be important for sexual signaling. Males can smell females which are fertile and ready to mate, and rams mark their territories by rubbing scent on to rocks. They have a four-chambered stomach which plays a vital role in digesting, regurgitating, and redigesting food. Domestic sheep are important for their wool, milk, and meat (which is called mutton or lamb).

The most populous species of sheep is the domestic sheep, the largest populations of which are found in China and Australia.

1 Sheep species
2 Wild sheep
3 References
4 See also

[edit] Sheep species

There are at least eight species of sheep:

	O. aries	Domestic sheep
	O. canadensis	Bighorn sheep
	O. dalli	Dall Sheep
	O. musimon, or O. ammon musimon	European Mouflon
	O. nivicola	Snow sheep
	O. orientalis	Asiatic Mouflon
	O. vignei	Urial
	O. ammon	Argali

[edit] Wild sheep

Wild sheep mostly found in hilly or mountainous habitats. They are fairly small compared to other ungulates; in most species adults weigh less than 100 kg (220 lb) (Nowak 1983). Their diet consists mainly of grasses, as well as other plants and lichens. Like other bovids their digestive system enables them to digest and live on low-quality, rough plant materials. Sheep conserve water well and can live in fairly dry environments. Their bodies are covered by a coat of thick hair to protect them from cold. The coat contains long, stiff hairs, called kemps, and a short woolly undercoat, called fleece, which grows in fall and is shed in spring (Clutton-Brock 1999).

Wild sheep are social animals and live in groups, called flocks. This helps them to avoid predators and also helps them stay warm in bad weather by huddling together. Flocks of sheep need to keep moving to find new grazing areas and more favorable climate as the seasons change. In each flock there is a sheep, usually a mature ram, which the others follow as a leader (Clutton-Brock 1999).

In wild sheep both rams and ewes have horns, with the rams' being much larger. The horns of a mature bighorn ram can weigh 14 kg (30 lb), as much as the rest of its bones put together. Rams use their horns to fight with each other for dominance and for the right to mate with females. In most cases they do not injure each other because they hit each other head to head and their curved horns do not strike each other's bodies. They are also protected by having very thick skin and a double-layered skull (Voelker 1986).

Wild sheep have very keen senses of sight and hearing. When detecting predators wild sheep most often flee, usually uphill to higher ground. However they can also fight back. The Dall sheep has been known to butt wolves off the face of cliffs (Voelker 1986).

[edit] References

Ram on stamp from the Faroe Islands

Bulanskey, S. 1992. The Covenant of the Wild. New York : William Morrow and Company, Inc. ISBN 0688096107
Clutton-Brook, J. 1999. A Natural History of Domesticated Mammals. Cambridge, UK : Cambridge University Press ISBN 0521634954
Huffman, B. 2006. The Ultimate Ungulate Page Website [1] Retrieved January 13, 2007
Miller, S. 1998. "Sheep and Goats". United States Department of Agriculture, Foreign Agricultural Service[2]
Nowak, R. M. and J. L. Paradiso. 1983. Walker's Mammals of the World. Baltimore, Maryland: The Johns Hopkins University Press. ISBN 0801825253
Oklahoma State University (OSU). 2003 Breeds of Livestock: Sheep[3] Retrieved January 13, 2007
Parker, D. 2001. The Sheep Book. Athens, Ohio, USA : Ohio University Press ISBN 0804010323
Voelker, W. 1986. The Natural History of Living Mammals. Medford, New Jersey: Plexus Publishing, Inc. ISBN 0937548081