Some believe that stripes adorn zebras to resist diseases, while others suggest that the animal’s markings act as a makeshift air-conditioner or predator repellent. Although researchers have yet to reach a final verdict, a recent study sponsored by National Geographic found that the hotter the temperature gets, the more stripes a zebra will have.

To solve this enigma, a team of researchers studied the plains zebra using a model that compares the average number of stripes among a regional population to a number of environmental factors. Using the information from their calculations, temperature showed the greatest correlation to striping patterns.

In fact, University of California biologist and study coauthor Brenda Larison explains, “We were able to show that we could predict [stripe frequency] with significant accuracy.”

So, what do we know for sure about zebra stripes? First off, the pestilence-spreading pests tend to avoid striped patterns, reports National Geographic.

“Diseases carried by horseflies are really nasty,” says fellow University of California biologist Tim Caro. “They can hold a lot of diseases like equine influenza and it’s possible that those diseases are going to be more of a problem under warmer, wetter conditions.”

Warmer conditions also require better built-in cooling mechanisms. Larson notes that zebras’ skin temperature is a few degrees lower than surrounding, non-striped mammals. To understand why, you need look no further than the contrast between black and white on a zebra’s skin. Since black absorbs more heat that white, the difference in temperature triggers a process known as convection, or the transfer of heat. Air circulates over the zebra’s skin, dipping it on average 3 degrees Celsius below the temperature of other nearby species.

“Why has the zebra come up with this crazy striping scheme? We think it’s because they’re trying to solve multiple problems with one solution,” adds Larison, according to USA Today.

While the researchers forged a link between temperature and skin patterns, the potential social functionality of stripes remains a mystery.

The study was originally published in the peer-reviewed journal Royal Society Open Science.