Researchers believe they've finally swatted away the scientific mystery of why zebras have stripes.
The animals' black-and-white pattern helps repel bloodthirsty, disease-carrying flies by disrupting their vision and making it difficult for the biters to land, according to a study by California scientists.
The study, which appears in the journal Nature Communications, supports the same conclusion reached by European researchers in 2012.
The purpose of the stripes has been an evolutionary puzzle that's generated five main hypotheses over the past 140 years: They are camouflage; they confuse predators; they manage the animals' body heat; they have an unknown social function; and they ward off tsetse and horseflies.
"I was amazed by our results," said lead author Tim Caro, a wildlife biologist at the University of California-Davis. "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."
Because the team relied on statistical modeling and did not directly observe the fly-repelling phenomenon in the wild, more specific study may be needed to definitively solve the riddle, another California university biologist told National Geographic.
"This is unlikely to be the last word on the subject," said Brenda Larison, at UCLA.
"We really need to know what happens with live zebras in the field before we can be sure," she said.