Zebra- Why do Zebras have Stripes?

Zebras in Lake Mburo National Park

Zebras with their conspicuous black and white stripes have become one of the iconic animals of Africa. A keystone species which people all over the world travel hundreds and thousands of miles to see.
So apart from the fame these striking markings have bought them what is the reason, the evolutionary benefits of their stripes?
The simple answer is no one knows for sure.

There are, however many theories. The most common and widespread of these is- camouflage. Zebra are typically residents of the wide open plains of Africa, making them appear very conspicuous. They make no effort to hide and are very noisy animals. So camouflage doesn’t seem to be their thing, but that is from a human point of view. Lions for example see the world very differently (see Lion Anatomy- The Eye). The startling black and white stripes may not be as startling to a lion. The fact that zebra are almost always in a tight herd, is thought to disrupt the individual outline of an animal as they bunch and move as one unit. Making it much harder for predators to pick out one zebra in the mass of stripes. So the black and white stripes although very noticeable to us, who see the colour spectrum very differently to lions, may in-fact be a highly evolved camouflage, aimed specifically at the large cats of Africa that are the main predators for these equines.

There are many other theories, but this is accepted as the main reason for the stripes.
It is interesting to note that, below each black stripe there is a greater concentration of blood vessels. This is thought to aid in thermo-regulation, as the black stripes heat up faster in the baking African sun. This creates a low pressure system on a micro scale. The natural pressure gradient between the high pressure above the white stripes and the low pressure above the black stripes creates air flow. Therefore helping to cool down the blood in the closely packed capillaries. Creating the same effect as an elephants ear ( see Elephant Anatomy- The Ear). This is a very plausible theory, as mentioned earlier zebra are plains animals, living in open savannah where the is little if any shade to occupy during the heat of the day.

So there are many theories and speculation about these beautiful animals, but there is no doubt that their coat reflect a highly evolved specialized species.

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