Scientists may never understand exactly why zebras have stripes, but 2019 research published in the Journal of Natural History suggests a plausible answer. The alternating black and white markings on zebras may be part of a cooling system that creates a current of air -- the result of convection -- that acts like a fan, helping their frothy sweat to evaporate and keeping the animals cooler. Alison and Stephen Cobb measured the temperature of the different color stripes on two zebras during a hot and sunny day in Kenya. They found that the black stripes absorbed more heat, causing a small-scale convective air movement that cooled the animals through the evaporative process.
Why zebras earned their stripes:
- The researchers also discovered that zebras can raise the hair on their black stripes, while the white ones remain flat, helping trigger the evaporation.
- The researchers concluded that the three components -- convective air movements, frothy sweat, and hair raising -- combine to wick the sweat away from their skin and help them cool down.
- Previous studies have suggested that the stripes are a form of camouflage, even though zebras spend large periods of time out in the open. Another study posited that the alternating colors disorient blood-sucking horse flies.