Zebras may have evolved their distinctive stripes as a way to interfere with flies' vision. Flies have difficulty landing on black-and-white surfaces because the light polarization screws up their ability to decelerate.
Recently, researchers in Japan painted black cows with zebra-like white stripes and discovered that flies stay away from them. Whoever painted the cows did good work, they look dapper.
From CNN:
A team of Japanese researchers recruited six cows and gave them each black-and-white stripes, black stripes and no stripes. They took photos of the cow's painted right side, counting the number of bites as they happened and watching how the cows reacted.
While unpainted cows and cows with black stripes endured upward of 110 bites in 30 minutes, the black-and-white cows suffered fewer than 60 in the same period, researchers found.
Image: PLOS/Attribution 4.0 International (CC BY 4.0)