It has long been a mystery why zebras are striped and other horse-like animals are not. Now the riddle has been solved. Zebras have stripes to protect them from biting flies, including horseflies and tsetse flies. Related animals don’t need stripes, because the flies can’t bite through their long hair. Only zebras have shorter hair that the flies can bite through.
The scientists drew maps of the areas where horses, asses, and zebras live in the wild. Then they overlaid them with other maps that indicate where the biting flies swarm. This showed that zebras’ habitation areas overlapped that of the flies. Some of the others’ areas overlapped, too; but their longer coats protect them from the flies.
But what do stripes have to do with flies?
It turns out that the flies avoid striped surfaces, so the stripes keep the zebras from getting bitten.
Now the new question is, “Why do biting flies avoid striped surfaces?” Nobody seems to have any idea yet. This is the way science works at its best. When a question is answered, it suggests at least one new question to be answered with new research. Maybe several.
Resource: UC Davis – News and Information, http://news.ucdavis.edu/search/news_detail.lasso?id=10879, Scientists solve the riddle of zebras’ stripes, 4-2-2914