Goat antelope

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Goat antelopes
Barbary Sheep, Ammotragus lervia
Barbary Sheep, Ammotragus lervia
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla
Family: Bovidae
Subfamily: Caprinae
Gray, 1821
Pantholopinae
Genera

Subfamily Caprinae
  Nemorhaedus
  Rupicapra
  Oreamnos
  Budorcas
  Ovibos
  Hemitragus
  Ammotragus
  Pseudois
  Capra
  Ovis
Subfamily Pantholopinae
  Pantholops

The term goat antelope usually means any of the species of mostly medium-sized bovids that make up the subfamily Caprinae (as treated here). The domestic sheep and domestic goat are both part of the goat antelope group, and the group itself is part of the family Bovidae, which in other branches contains the antelopes and domestic cattle. "Goat antelope" also sometimes refers to the Tibetan antelope.[clarify]

Contents

[edit] Characteristics

Although most goat antelopes are gregarious and have a fairly stocky build, they diverge in many other ways. For example the Musk Ox (Ovibos moschatus), is adapted to the extreme cold of the tundra; the Rocky Mountain goat (Oreamnos americanus), of North America is specialised for very rugged terrain; the Urial (Ovis orientalis) occupies a largely infertile area from Kashmir to Iran, including much desert country. The European mouflon (Ovis musimon) is thought to be the ancestor of the modern domestic sheep (Ovis aries).

Many species became extinct since the last ice age, probably largely because of human interaction. Of the survivors:

  • five are classified as endangered,
  • eight as vulnerable,
  • seven as of concern and needing conservation measures, but at lower risk, and
  • seven species are secure.

Members of the group vary considerably in size, from just over a metre long for a full-grown grey goral (Nemorhaedus goral), to almost 2.5 metres long for a musk ox, and from under 30 kg to more than 350 kg. Musk oxen in captivity have reached over 650 kg.

In lifestyle, the caprids fall into two broad classes, resource-defenders which are territorial and defend a small, food-rich area against other members of the same species, and grazers, which gather together into herds and roam freely over a larger, usually relatively infertile area.

The resource-defenders are the more primitive group: they tend to be smaller in size, dark in colour, males and females fairly alike, have long, tassellated ears, a long mane, and dagger-shaped horns. The grazers evolved more recently. They tend to be larger, highly social, and rather than mark territory with scent glands, they have highly evolved dominance behaviours. There is no sharp dividing line between the groups, but a continuum between the serows at one end of the spectrum and sheep, true goats, and musk oxen at the other.

[edit] Evolution

The goat antelope or caprid group is known from as early as the Miocene, when members of the group resembled the modern serow in their general body form[1]. The group did not reach its greatest diversity until the recent ice ages, when many of its members became specialised for marginal, often extreme, environments: mountains, deserts, and the Subarctic region.

The ancestors of the modern sheep and goats (both rather vague and ill-defined terms) are thought to have moved into mountainous regions – sheep becoming specialised occupants of the foothills and nearby plains, and relying on flight and flocking for defence against predators, and goats adapting to very steep terrain where predators are at a disadvantage.

[edit] Classification

Spanish Ibex (Capra pyrenaica)
Spanish Ibex (Capra pyrenaica)

FAMILY BOVIDAE

[edit] References

  1. ^ Geist, Valerius (1984). in Macdonald, D.: The Encyclopedia of Mammals. New York: Facts on File, 584-587. ISBN 0-87196-871-1.