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  • Scientists Solve the Mystery of Why Zebras Have Stripes

    first_img Watch: Dolphin Leaps Feet Away From Unsuspecting SurferWatch: Deep-Sea Octopus ‘Billows Like a Circus Tent’ Stay on target Stripes are fashionable on humans, but it turns out the pattern serves a greater purpose for zebras: pest control. According to a new study, zebra’s stripes appear to confuse flies, discouraging them from landing for a quick bite.For the study, published Wednesday in the journal PLOS One, researchers camouflaged horses in “zebra costumes.” They found that horse flies gathered around domestic horses and zebras at a similar rate — but landed on zebras a quarter as often.When solid-colored horses were dressed in the “zebra coats” the flies made far fewer landings on the patterned areas, but still landed on the uncovered, non-striped head.With solid coats of brown or gray, “most mammals are pretty boring,” Tim Caro, who studies animal coloration at the University of California, Davis, and a co-author of the study, told the New York Times. “So when you see these bold patterns like on a giraffe or zebra, as a biologist you say, Why?”The team said the research not only supported previous work suggesting stripes might act to deter insects, which can carry diseases, but helped unpick why, revealing the patterns only produced an effect when the flies got close.Researcher investigate how horseflies behave around horses with ‘zebra coats’ for an an experiment led by UC Davis focused on why zebra stripes are so good at warding off flies. (Tim Caro/UC Davis)The study noted that zebras and horses respond very differently to the presence of flies. Zebras swish their tails almost continuously during the day to keep flies off; they stop feeding if bothered by them; and if the flies are particularly persistent, the zebras will run from them. Horses, on the other hand, primarily twitch and occasionally swish to ward off flies. As a result, any flies that actually contacted zebras were soon dislodged compared to horses.The study also showed stripes did not act as a long-range deterrent but appeared to “dazzle” the flies that got up close — possibly because of the flies’ low-resolution vision.“From distances of greater than two metres or so, a zebra would just look like a grey horse – they won’t be able to see the stripes at all,” Dr Martin How, co-author of the research, told the Guardian. He said it was likely the “sudden reveal” of the stripes on close approach either surprised the insects and made them veer off, or interfered with their perception of how fast objects were moving past them, affecting their ability to land.The study also showed stripes did not act as a long-range deterrent but appeared to “dazzle” the flies that got up clos. (Photo Credit: Digital Vision/Getty Images)For years, scientists have debated the function of the stripey animal print. Some researchers have said the stripes serves as camouflage to confuse big predators, an identity signal to other zebras, or even a kind of wearable air conditioner, according to the Times. Now most scientists agree that the function of a zebra’s stripes is to ward off biting flies.Researchers do not yet understand why zebras evolved these sophisticated defense mechanisms, according to a UC Davis statement. A possible explanation is zebras may be highly prone to infectious diseases carried by African biting flies, although that hypothesis requires further study.More on Geek.com:This ‘Virgin’ Stickleback Fish Mysteriously Fertilized Its Own EggsPhotos: London Zoo Shares Amazing Animal X-RaysScientists Solve the Mystery of the Cassowary’s Strange Headgearlast_img read more