A recent study reveals that Zebras' stripes don't do much to help them hide from predators. So why do they have them?
Zebras are known for their distinctive black and white stripes, but they may not only be used for camouflage as once thought. According to a report from UPI, a recent study reveals that the stripes on zebras do little to protect them from predators in the wild. So what’s the deal behind the notorious pattern?
Scientists at the University of California, Davis have offered an intriguing new insight into the study of zebra stripes. In their most recent report, they assert that biologists have long examined the effect of zebra stripes on their ability to hide from human eyes.
For the majority of their evolutionary history, zebras have not had to worry about hiding from humans. Their camouflage patterns would have evolved in response to their natural predators – lions, cheetahs, tigers, and other large mammals that prowl the savannahs for food. Given this notion, researchers set out to see how a zebra would appear through the eyes of a large predatory cat.
According to the recent study’s lead author, assistant professor of biological anthropology from the University of Calgary, Amanda Melin, “We carried out a series of calculations through which we were able to estimate the distances at which lions and spotted hyenas, as well as zebras, can see zebra stripes under daylight, twilight, or during a moonless night.”
The scientists tried to detect a zebra under the conditions where camouflage would matter the most; through short shrubs and bushes on a dark, moonless night. They found that zebra stripes would be spotted by a big cat at 29 feet under these conditions, and would be spotted at a distance of 98 feet under twilight. At these distances, however, predators would be more likely to rely on their senses of hearing and smell to detect prey, meaning that any camouflage patterns would be rendered useless.
The scientists also ruled out any explanation that would say zebras use their stripes for social purposes; a zebra would be unable to distinguish between stripes and a solid pattern at long distances, meaning they don’t use their stripes to recognize one another.
According to co-author Tim Caro, a professor of wildlife biology at UC Davis, “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. Instead, we reject this long-standing hypothesis that was debated by Charles Darwin and Alfred Russell Wallace.”
A press release from UC Davis describing the details of the recent study can be found here.