If Not For Camouflage, Why Do Zebras Have Stripes?
Why do zebras have stripes? One study that seeks to answer the question has raised several more by pointing out that stripes are definitely not for camouflage.
According to Christian Science Monitor, researchers from University of California Davis conducted a study in which they tested the camouflage hypothesis. By simulating the vision of zebra predators, they ruled that stripes did not evolve to provide camouflage as the hunters can easily smell prey from a distance when stripes become visible.
"The results from this new study provide no support at all for the idea that the zebra's stripes provide some type of anti-predator camouflaging effect," study author Tim Caro said. "Instead, we reject this long-standing hypothesis that was debated by Charles Darwin and Alfred Russell Wallace."
To arrive at these findings, researchers ran images of zebra taken from the wild in various digital filters that simulate the vision of predators like lions and hyenas. They found that most predators cannot see zebra stripes beyond 50 meters in daylight and not beyond 30 meters during twilight. At this distance, predators would have already smelt their prey.
Through the study, researchers also ruled out stripes helping zebras in recognizing other members of the species.
With a longstanding hypothesis now discredited, it remains to be known what purposes zebra stripes serve.
The study has been published in PLOS One.