Over the years, there have been any number of theories as to why zebras are striped. Some have said it’s for camouflage, some that it affects mating preferences, and some even proposing that it’s an individual identification system that they use to tell each other apart. All of these theories were simply speculative, however, and never held up to scientific scrutiny.
So why the stripes? Blame the flies, says a new study from the University of California-Davis.
Lead researcher Tim Caro and his group of researchers decided to take a different approach to the stripe question, trying instead to look for ecological differences between different species and subspecies of zebras with varying levels of “striped-ness”.
They discovered a strong statistical correlation between the amount of striping and the level of biting flies. Here’s Caro:
“Again and again, there was greater striping on areas of the body in those parts of the world where there was more annoyance from biting flies.”
More specifically, species living in areas that are also inhabited by tsetse flies (African biting flies that are the main carriers of trypanosomiasis, or “sleeping sickness”) tend to be striped, while those living in areas without the fly tend to be solid.
Studies as far back as the 1930s have proven that flies prefer to land on surfaces that are all one solid color over surfaces that are striped.
Read more from The Guardian here.