Are Stripes A Zebra's Cooling System?

Jan 17, 2015
Originally published on January 17, 2015 9:57 am
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SCOTT SIMON, HOST:

Staying in Africa for a moment - do you ever see a zebra standing against a grassy plain and ask, who do you think you're fooling? Scientists since Darwin have been trying to fathom zebra stripes. Some have suggested the stripes might be nature's bug repellent, since flies just aren't attracted to the pattern of light that reflects off those black and white stripes. There comes another theory too, from researchers in the Royal Society Open Science magazine who advance what they call the cooling eddy theory. Black stripes get hotter than white, so you get faster or slower air currents over the zebra's skin. That creates eddies, or air swirls, to cool the zebra, maybe as it runs from a lion. Think of it as air conditioning on the go. Sure enough, the study found that zebras in hotter environments tended to have more stripes than their compatriots in cooler areas. Scientists say further investigation is required, but it will not be easy. Those vivid marks even stumped the imagination of Rudyard Kipling and his "Just So Stories." Kipling explains how the leopard got his spots and the camel his hump, but not how the zebra got his stripes. Transcript provided by NPR, Copyright NPR.