Have you ever wondered why Zebras have stripes? It was thought by scientists that zebras developed stripes as part of an evolutionary adaptation to help them ward off bloodsucking flies.

Tim Caro, a biologist, had announced last year that zebras have stripes because it’s an evolutionary advantage and having them ward off flies. He added that it is particularly important for zebras because they have such thin coats of hair.

The Royal Society Open Science says otherwise. The new study reports that Zebras have stripes because of the environment, particularly temperature.

Brenda Larison, a biologist at the University of California, and her colleagues analyzed 16 zebra populations throughout Africa and studied the stripe patterns in the plains zebra, the most common species of zebra. The team measured 29 different environmental factors. They took into consideration soil moisture, rainfall, prevalence of disease, carrying tsetse flies and the number of lions in their areas. Specifically, these zebras are found in the grasslands of eastern and southern Africa.

The scientists realized that striping patterns were most highly correlated with temperature. The study adds the warmer the climate, the more stripes found on the zebra.

“In contrast to recent findings, we found no evidence that striping may have evolved to escape predators or avoid biting flies. Instead, we found that temperature successfully predicts a substantial amount of the stripe pattern variation observed in plains zebra.”

So Zebras have stripes, but what about their function? The study says it could be that the stripes help keep the zebra cool, or serve some other purpose. Bottom line, they’re not sure.

The researchers conclude, “Much additional work is needed to elucidate the true functionality of striping in zebra. Our work shows a correlation with temperature, but the cause of this correlation remains unknown.”

[photo credit: Rennett Stowe]