Mechanism

Zebras are African horses best known for their distinctive white and black stripes. Their stripes come in different patterns unique to each individual. Unlike their closest relatives, horses and donkeys, zebras have never been truly domesticated.

They have been the subject of African folk tales which tell how they got their stripes. According to a Bushmen folk tale of Namibia, the zebra was once all white but got its black stripes after a fight with a baboon over a waterhole. After kicking the baboon so hard the zebra lost his balance and tripped over a fire, the fire sticks left scorch marks all over this white coat.

Some zoologists believe that the stripes act as a camouflage mechanism. This is accomplished in several ways. First, the vertical striping helps the zebra hide in grass. While seeming absurd at first glance, considering that grass is neither white nor black, it is supposed to be effective against the zebra’s main predator the lion, which is color blind. Theoretically, a zebra standing still in tall grass may not be noticed at all by a lion.

Additionally, since zebras are herd animals, the stripes may help to confuse predators. A number of zebras standing or moving close together may appear as one large animal, making it more difficult for a lion to pick out any single zebra to attack. A herd of zebras scattering to avoid a predator will also represent a confused mass of vertical stripes travelling in multiple directions making it difficult for the predator to track an individual visually as it separates from its herdmates.

More recent theories, supported by experiment, posit that the disruptive coloration is also an effective means of confusing the visual system of the tsetse fly. Alternative theories include that the stripes coincide with fat patterning beneath the skin, serving as a thermoregulatory mechanism for the zebra, and that wounds sustained disrupt the striping pattern to clearly indicate the fitness of the animal to potential mates.

Zebras have excellent eyesight. It is believed that they can see in color. Like most ungulates the zebra has its eyes on the sides of its head, giving it a wide field of view. Zebras also have night vision, although not as advanced as that of most of their predators, but their hearing compensates.

They also have great hearing, and tend to have larger, rounder ears than horses. Like horses and other ungulates, zebra can turn their ears in almost any direction. In addition to eyesight and hearing, zebras have an acute sense of smell and taste.

Modern man has had great impact on the zebra population. Zebras were, and still are, hunted mainly for their skins. The Cape mountain zebra was hunted to near extinction with less than 100 individuals by the 1930s. However the population has increased to about 700 due to conservation efforts. Both Mountain zebra subspecies are currently protected in national parks but are still endangered.

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