Climate key to stripes

There have been various theories on how the zebra got its stripes, ranging from those which say that the stripes make it difficult for predators to spot it to those which say they help ward off biting flies. A study whichanalysed the impact of 29 environmental factors, such as heat, flies and predators, on zebras across 16 locations in Africa found that temperature was the only variable with which zebra stripes had a correlation. Stripes help the zebra regulate its body temperature as they heat up at different rates and create "eddies of air" that have a cooling effect. This mechanism works best when stripes are bold. As a result zebras in areas with lower temperature have fewer and fainter stripes. 

Source

Down To Earth, February, 2015