A goat antelope is any of the 26 species of mostly medium-sized herbivores that make up the subfamily Caprinae or the single species in subfamily Panthalopinae. 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.

The goat antelope or caprid group is known from as early as the Miocene, but 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 sub-Arctic region. In consequence, although most goat antelopes are gregarious and have a fairly stocky build, they diverge in many other ways. The Musk Ox became adapted to the extreme cold of the tundra; the Mountain Goat of North America specialised in very rugged terrain; the Urial, probable ancestor of modern Domestic Sheep, occupied a largely infertile area from Kashmir to Iran, including much desert country.

Many of the ice age species are now extinct, probably largely because of human interaction. Of the survivors, no less than 5 are classifed as endangered, 8 as vulnerable, 7 as of concern and needing conservation measures but at lower risk, and just 7 species are secure.

Members of the group vary considerably in size, from just over a metre for a full-grown Goral to almost 2.5 metres for a Musk Ox, and from under 30 kilos to more than 350 kilos. Musk Oxen in captivity have reached over 650 kilos.

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, tasselated 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, just a continuum between the serows at one end of the spectrum and sheep, true goats, and Musk Oxen at the other.

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 clumping for defence against predators; goats adapting to very steep terrain where predators are at a disadvantage.

• FAMILY BOVIDAE
  • Subfamily Bovinae: cattle and spiral-horned antelopes, 24 species in 9 genera
  • Subfamily Cephalophinae: duikers, 19 species in 2 genera
  • Subfamily Hippotraginae: grazing antelopes. 23 species in 11 genera
  • Subfamily Antilopinae: gazelles, dwarf antelopes and the Saiga, 38 species in 14 genera
  • Subfamily Caprinae
    • Mainland Serow, Capricornis sumatraensis
    • Japanese Serow, Capricornis crispus
    • Goral, Nemorhaedus goral
    • Chamois, Rupicapra rupicapra
    • Pyrenean Chamois, Rupicapra pyrenaica
    • Mountain Goat, Oreamnos americanus
    • Takin, Budorcas taxicolor
    • Musk Ox, Ovibos moschatus
    • Himalayan Tahr, Hemitragus jemlahicus
    • Nilgiri Tahr, Hemitragus hylocrius
    • Arabian Tahr, Hemitragus jayakari
    • Barbary Sheep, Ammotragus lervia
    • Blue Sheep, Pseudois nayaur
    • Wild Goat, Capra aegagrus
    • Ibex, Capra ibex
    • Markhor, Capra falconeri
    • East Caucasian Tur, Capra cylindricornis
    • West Caucasian Tur, Capra caucasia
    • Urial, Ovis orientalis
    • Argali, Ovis ammon
    • Mouflon, Ovis musimon
    • Snow Sheep, Ovis nivicola
    • Thinhorn Sheep, Ovis dalli
    • American Bighorn Sheep, Ovis canadensis
    • Domestic Sheep, Ovis aries
  • Subfamily Panthalopinae
    • Chiru, Panthalops hodgsoni