BOB HIRSHON (host):
Why zebras have stripes. I’m Bob Hirshon and this is Science Update.
Jenneva Schumacher’s eighth grade class at North Royalton Middle School in Ohio wrote to ask why zebras have stripes. We turned to behavioral ecologist Martin Stevens from the University of Cambridge in England. He says while stripes are conspicuous during the day, they could provide camouflage once daylight fades.
MARTIN STEVENS (University of Cambridge):
Many predators hunt at dusk when the stripes may start to merge and start to have a disruptive effect and almost break up the form of the zebra in fairly dim light conditions. So you can imagine a lion hunting at dusk can find it difficult to pick out the zebra against the background."
He says stripes may protect zebras by helping individuals blend in with the rest of the herd. Another possibility is that the stripes confuse deadly tsetse flies, making them less likely to bite. I’m Bob Hirshon for AAAS, the science society.