Why do zebras have stripes?

Why do zebras have stripes? Writing in the Journal of Natural History, husband-and-wife team Alison and Stephen Cobb claim that the iconic colour pattern helps regulate body temperature.
The black stripes on a white background were seen traditionally as a form of camouflage. That might seem an odd suggestion when seeing these brightly coloured animals in zoos, but it’s entirely plausible on encountering them in their native African habitat. Zebras blend into the savannah background, their profiles broken up by stripes mimicking shafts of vegetation.