Seen from the air, it could be a crazy patchwork of dark waterways and sandy spits, or perhaps narrow plots of land -- some dark, some light -- laid out in a desert and awaiting the first hint of green. From up close, and as close as our long lenses can reach, it is a pure geometry of survival, painted on zebras' flanks, necks and heads.
If this kaleidoscope of stripes, which move constantly when a herd of zebras is in its full escape flight, seems disorienting, it is supposed to be. Dazzling, unsettling, unfocussed; all this. And that's why -- for many years now -- the answer to "why do zebras have stripes?" was quite firm: to mislead and confuse big predatory cats in their intense pursuit of sweet zebra flesh.
But a new theory suggests that air currents caressing a zebra move fast over its dark and heat absorbing stripes, and slow when flowing over the light ones. As these airflows converge, the swirling air cools the skin, particularly of the animals whose dark stripes are heavily clustered. The difference of the body temperature between a zebra and a plain-skinned herbivore in the same part of Africa may reach several degrees Fahrenheit, making the zebra a truly cool animal. Another theory proposes that many disease-carrying insects avoid striped animal skin, perhaps leaving zebras alone -- and not infected. ©Yva Momatiuk
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