Photograph by Martin Harvey, Corbis
Photograph by Martin Harvey, Corbis

For Zebras on the Run, Stripes May Provide Protection

The theory known as “motion dazzle” suggests that dramatically patterned animals in motion can confuse, and elude, their predators.

This story appears in the July 2016 issue of National Geographic magazine.

If a zebra zigs, will its stripes make a predator zag? That’s the idea behind motion dazzle, a century-old hypothesis about why some animals sport high-contrast patterns. Unlike camouflage, which allows prey to blend into surroundings, motion dazzle may mask movement, confusing predators about direction and speed. “We have all these ideas about animal patterns,” says Cambridge University biologist Laura Kelley, “but very few of these hypotheses have actually been tested.”

To find out whether patterns make prey difficult to catch, Kelley and her colleagues have developed an online game with humans as the predators. Dazzle Bug players try to nab patterned “bugs” skittering across natural backgrounds. The easy-to-catch critters disappear; the evasive ones reproduce. Eventually only the hardest-to-catch patterns remain. Says Kelley, “We’re trying to determine the ideal pattern for avoiding capture during movement.”