Equus quagga, Equus zebra, Equus grevyi
The zebra is a member of the African equids of the family Equidae and genus Equus recognized for its distinctive black and white stripes. The stripes run vertically on its head and franks where as the ones at the rear and the limbs appear horizontal and the belly/ under part is white. Though most people believe that the original color of the zebra is white with black stripes, research has proved the reverse to be true. Scientists have confirmed that the Zebra is generally black with the white stripes running down its body making it one of the most beautiful and conspicuous animals in the world. They are believed to have evolved within the old world horses about 4 million years ago.
The English noun zebra has unclear origin as some sources claim it originated from the Italian zebra which is said to have also been adopted from Portuguese with a Congolese origin. Other sources claim it stemmed from Latin word ‘equiferus’ meaning ‘wild horse’; from equus (‘horse’) and ferus (‘wild/ untamed’).
There are only 3 species which all live in Africa; the Grévy’s zebra, Mountain Zebra and the Plain zebra also known as the common zebra or Burchell’s zebra. The Grévy’s zebras and Mountain Zebras are, together with asses and donkeys, in a separate lineage from other zebra lineages which gives an impression that either striped equids evolved more than once, or that common ancestors of zebras and asses were striped and only zebras retained the stripes.
The Mountain Zebra inhabits the dry mountainous areas of South West Africa in the countries of Angola, South Africa and Namibia where as the Grevy’s zebra lives in the North east Africa in Kenya and Ethiopia. The Burchell’s zebra occupies the savanna grasslands and woodlands of East Africa mostly Kenya, Uganda and Tanzania.
The Zebra weighs up to 350 kg and is about 1.3 m tall at shoulder with a body length ranging from 6–8.5 feet (2–2.6 m) with an 18-inch (0.5 m) long tail. The males (stallions) appear slightly bigger than the females (mares) like most mammals. The zebra has a mane that is also covered with strips which stands erect. Each animal’s stripes are as unique as fingerprints in humans; no two zebras are exactly alike although each of the three species has its own general pattern.
Many scientists have come up with hypotheses to why the zebra has the stripes though not fully convincing. Most of them have come into a concession that probably the stripes were developed in order to camouflage from the predator since when seen in the late hours of the day, the stripes match into grayish colour that may confuse a predator since it blends with the vegetation. They also suggested that these stripes may make the predator to fail to determine the exact distance of the Zebra when chasing it hence an adaptation to survive in the wild with several predators.
Other scientists suggested that the stripes developed as a mechanism to discourage the tsetse flies and horse flies that not only drain the animal’s blood but also spread diseases to the animal. It was largely agreed that these flies do not like stripped surfaces but rather prefer all- white or black surfaces hence making the zebra a bit safer from their bites. Although most of them agreed with this finding that stripped surfaces are not favorites for the flies, none of them could find out why.
The Zebra is a nomadic herbivore largely feeding on grass though it may sometimes also feed on tree backs, shoots and leaves. Zebras largely depend on water and often drink water at least once in a day. During drought, zebras will often migrate for green pastures but some times in the dry season, they can live on dry grass only if they are within a short distance (usually no farther than 20 miles away) from water holes. When grazing or going to the water holes, the adult mare takes a lead and the rest follow in a file with each having its foal right behind it and the dominant stallion guards in the rear. They normally follow in a hierarchical manner with the least influential individual at the end of the file.
The zebras communicate with high pitched barks and whinnying. Grévy’s zebras make mule like brays. A zebra’s ears connote its frame of mind. When a zebra is in a peaceful, tense or friendly mood, its ears stand erect, when it is frightened, the ears are pushed forward, and when angry, they are pulled backward. When surveying an area for predators, zebras will stand in an alert posture; with ears erect, head held high, and staring. When tension increases, they will also snort and after spotting a predator, it will bark or bray loudly.
The Mountain and Burchell’s zebras raise their foals together with the head stallion and other mares in the herd and there is strong love among the members unlike the Grevy’s zebra which protects her foal alone since they always part after a few months. Like their family relatives –the horses, zebras are able to stand, walk and suckle shortly after they are born.
The zebra has a life span of up to 28 years in the wild and is preyed up on by lions and hyenas and sometimes hunting dogs, leopards and cheetahs. They have been also known to mix with other animals especially antelopes hence improving their safety. Zebras also have been known to sleep while standing and more especially when there are other individuals grazing around or on guard.
Their defensive mechanism is composed of running at high speeds of about 65km/hr in a zigzag way and sometimes standing in semi-circles ready to bite the enemy. Its strongest weapon is its strong hind kicks which are known to kill even lions.
The zebra has an excellent eye sight with good night vision and can see in colour. It also has a good sense of smell and taste in addition to an acute hearing sense with its large round ears. The Grevy’s Zebra is distinctly the largest of all the 3 species while the mountain Zebra is the smallest of the 3.
Both the Grevy’s zebra and the Mountain zebra are listed as endangered while plains zebra (Burchell’s zebra) populations remain plentiful and is listed as Least Concern by the IUCN, though their numbers declined greatly in the last century.
The 3 species of Zebra all exist in the wild only in Africa. Grevy’s zebra, named after Jules Grevy, a president of France in the 1880s who had received one from Abyssinia as a gift, is now found mostly in northern Kenya and Ethiopia while the Mountain zebra is found in southern and southwestern Africa in the dry mountains of Namibia, Angola and South Africa and the Burchell’s, also known as the common or plains zebra exist in numerous numbers in most East African countries (Kenya, Tanzania and Uganda).