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| Sunday, 6 March 2005 |
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Junior Observer |  |
| News Business Features Editorial
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In black and white
Striking and fascinating with their striped coats of black and white, zebras are exclusively African animals. Zebras are generally gregarious (sociable), living in family groups of six to eight, comprising an adult male, several females and their foals. Most often, these family groups join others and form large herds containing more than hundred animals. The herd stays together during the whole year under the leadership of the oldest and most experienced stallion. The young male zebras (up to three years old) form isolated groups. The normally gentle animals show a little restlessness when they are vying for the affection of females. The males throw themselves at each other in violent but bloodless fights. Although all zebras look superficially the same, various species such as the Burchell's, Grant's, Grevy's and Chapman's have different coat patterns, and also differ in the general appearance of the body. Some zebras have more elegant shapes and look very much like horses; others are more squat and resemble donkeys. Even their coat patterns differ from one to the other, but we cannot notice this at a glance. However scientists are able to tell them apart, by comparing the width of the stripes and the overall patterning.
You may wonder why zebras have such unusual striped coats in the first place, because they are so striking and sure seem very easy to be spotted by a predator. But in reality, these striking stripes are an excellent camouflage for them in the Savannahs, where bright light produces shadows of intense contrasts. The contrasting coloured stripes help the zebras display a form of camouflage called 'disruptive colouration'. As zebras roam in herds, when they are close together, their patterning makes it very difficult for a predator to identify an individual zebra. All that the predator sees is a mass of black and white pattern, and this makes it hard for it to attack one particular animal. All the species of zebras have similar habits, though the different species do not normally live together, except for Burchell and Grevy Zebras.
These active animals often graze with other ruminants (cud-chewing animals), such as gnu, sharing the food without any competition. It seems that the gnu eats a certain type of grass, when it is fresh, and only just beginning to grow, while the zebras eat the same grass, but at a later stage of growth. Zebras graze all day, and are on the move constantly in search of food. Only during the hottest part of the day, when the heat becomes intolerable, do they rest in the shade of the few leafy acacia trees, chewing the cud. These animals which are sociable could be seen grazing alongside antelope and gazelle too. Ostriches too are always welcome members of such herds; their acute vision and the zebra's sensitive sense of smell combine to make an excellent alarm system against predators.
Female zebras give birth after one year of gestation and the foals are able to follow the movements of the herd which lead a nomadic life, a few hours after birth. The young zebras do not have bright stripes as their parents do. The stripes are paler and become darker as they grow. Water is indispensable for the survival of zebras. They are exposed to danger when they are at the waterhole, because they are not as alert as at other times. Even the presence of one or two guards is not sufficient to save the lives of weak, sick or old animals from the jaws of a leopard, lion or a pack of ferocious Cape Hunting Dogs. When the zebras are not at the waterhole, they are very vigilant and
more united. They know how to defend themselves with their hooves, making
the life of hungry predators very difficult. |
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