Sunday 31 December 2017


ZEBRA


Zebras are several species of African equids (horse family) united by their distinctive black and white striped coats. Their stripes come in different patterns, unique to each individual. They are generally social animals that live in small haremsto large herds. Unlike their closest relatives, horses and donkeys, zebras have never been truly domesticated.

There are three species of zebras: the plains zebra, the mountain zebra and the Grévy's zebra. The plains zebra and the mountain zebra belong to the subgenus Hippotigris, but Grévy's zebra is the sole species of subgenus Dolichohippus. The latter resembles an ass, to which zebras are closely related, while the former two look more horse-like. All three belong to the genus Equus, along with other living equids.

The unique stripes of zebras make them one of the animals most familiar to people. They occur in a variety of habitats, such as grasslands, savannas, woodlands, thorny scrublands, mountains, and coastal hills. However, various anthropogenic factors have had a severe impact on zebra populations, in particular hunting for skins and habitat destruction. Grévy's zebra and the mountain zebra are endangered. While plains zebras are much more plentiful, one subspecies, the quagga, became extinct in the late 19th century – though there is currently a plan, called the Quagga Project, that aims to breed zebras that are phenotypically similar to the quagga in a process called breeding back.


Representative Species


Grévy's zebra
Scientific name: Equus grevyi
Higher classification: Equus
Rank: Species



The Grévy's zebra (Equus grevyi), also known as the imperial zebra, is the largest extant wild equid and the largest and most threatened of the three species of zebra, the other two being the plains zebra and the mountain zebra. Named after Jules Grévy, it is the sole extant member of the subgenus Dolichohippus. The Grévy's zebra is found in Kenya and Ethiopia. Compared with other zebras, it is tall, has large ears, and its stripes are narrower.

The Grévy's zebra lives in semi-arid grasslands where it feeds on grasses, legumes, and browse; it can survive up to five days without water. It differs from the other zebra species in that it does not live in harems and has few long-lasting social bonds. Male territoriality and mother–foal relationships form the basis of the social system of the Grévy's zebra. This zebra is considered to be endangered. Its population has declined from 15,000 to 3,000 since the 1970s. However, as of 2008, the population is stable.




Mountain zebra
Scientific name: Equus zebra
Rank: Species
Higher classificationEquus

The Mountain zebra
(Equus zebra) is a threatened species in the family Equidae. It is native to south-western Angola, Namibia and South Africa.









Plains Zebra
Scientific name: Equus quagga
Higher classification: Equus
Rank: Species


The Plains zebra (Equus quagga, formerly Equus burchellii), also known as the common zebra or Burchell's zebra, or locally as the "quagga" (not to be confused with the extinct subspecies), 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 recognized 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. As of 2016, the plains zebra is classified as Near Threatened by IUCN.

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 rain forest and permanent wetlands, and rarely stray more than 30 kilometers from a water source. Predators of the zebra include lions, spotted hyenas, leopards, cheetahs and wild dogs.


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 to defend his harem. The species population is stable and not endangered, though some populations such as in Tanzania have declined sharply.

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