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The plains zebra (''Equus quagga'', formerly ''Equus burchellii''), also known as the common zebra or Burchell's zebra, is the most common and geographically widespread species of zebra. It ranges from the south of Ethiopia through East Africa to as far south as Botswana and eastern South Africa. The plains zebra remains common in game reserves, but is threatened by human activities such as hunting for its meat and hide, as well as competition with livestock and encroachment by farming on much of its habitat. Subspecies include the extinct quagga and six recognised extant subspecies, though there is great variation in coat patterns between individuals. The striping pattern is unique among ungulates in the region, and its functions are disputed. Suggested functions include crypsis, forms of motion camouflage, social signaling and recognition, and discouraging biting flies. The plains zebra's range is fragmented, but spans much of southern and eastern Africa south of the Sahara. Its habitat is generally but not exclusively treeless grasslands and savanna woodlands, both tropical and temperate. They generally avoid desert, dense rainforest and permanent wetlands, and rarely stray more than 30 kilometres from a water source. The plains zebra is a highly social species, forming harems with a single stallion, several mares and their recent offspring; there are also bachelor groups. Groups may come together to form herds. The animals keep watch for predators rather than attempting to hide; they bark or snort when they see a predator, and the harem stallion attacks predators such as dogs, hyenas and leopards to defend his harem. The species population is stable and not endangered, though some populations such as in Tanzania have declined sharply. ==Taxonomy== There is a dispute among biologists as to how to properly classify the various species of zebra. It is thought that the plains zebra and mountain zebra belong to the subgenus ''Hippotigris'' and that Grévy's zebra is the sole species of subgenus ''Dolichohippus''. This is on account of Grévy's zebra resembling an ass (subgenus ''Asinus''), while the plains zebra and mountain zebra are more horse-like. All three animals belong to the genus ''Equus'' along with other living equids. However, recent phylogenetic evidence suggests that the mountain zebras and Grévy's zebras should be classified with asses and donkeys in a lineage separate from the plains zebra. In areas where plains zebras are sympatric with Grévy's zebras, it is not unusual to find them in the same herds〔 and fertile hybrids occur.〔J. E. Cordingley, S. R. Sundaresan, I. R. Fischhoff, B. Shapiro, J. Ruskey, D. I. Rubenstein (2009). Is the endangered Grevy's zebra threatened by hybridization?. Animal Conservation. 12: 505–513.〕 In captivity, plains zebras have been crossed with mountain zebras. The hybrid foals lacked a dewlap and resembled the plains zebra apart from their larger ears and their hindquarters pattern. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Plains zebra」の詳細全文を読む スポンサード リンク
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