Have you ever wondered if the stripes on zebras have any purpose at all? Sure they make the zebras unique and interesting, but more than that, the stripes help zebras fend off parasites.
In an article on The Atlantic, Ed Yong writes that the stripes on zebras make them a hard target for horseflies based on experiments on horses.
“By putting black-and-white coats on horses, a new study shows that the pattern discourages biting flies from landing… several researchers, over the years, have shown that these flies find it hard to land on striped surfaces,” Yong wrote.
By watching and filming the stable’s horses and zebras, the team confirmed that horseflies were much worse at alighting on the latter. The flies had no problem finding the zebras or approaching them, but couldn’t stick the landing. “You get a quarter as many landings,” Caro said. “The flies just can’t probe for a blood meal with the zebras.”
The team found the same trend when they put striped coats on the horses. Cloaked in stripes, the very same animals suddenly became more resistant to flies, except on their uncovered heads. And uniformly colored coats had no effect; the stripes, specifically, befuddled the flies.