We still don’t understand why zebras have stripes. Although earlier this year, the New York Times reported the stripes are likely meant to deter flies that carry deadly disease.
To test this theory, Japanese scientists recently painted cows with zebra stripes and analyzed the amount of insect bites they received, compared to the bovines that were left blank.
The scientists expected that the painted cows would both avoid fly attacks and show fewer “fly-repelling behaviors” like tail flicks and leg stamps, per the study, published in PLOS One. So they painted two cows with black and white stripes, two with just black stripes, and two with no stripes at all.
The zebra stripes indeed prevented fly attacks. In fact, cows with those stripes saw a 50 percent reduction in flies even landing on them.