Zebra stripes have been boggling scientists for decades. Many believe the stripes act as a camouflage mechanism, but researchers from the University of California, Davis said that scientists have been looking at zebra stripes the wrong way.
In general, zebra are more concerned in avoiding tigers, cheetahs, lions and other animal predators than human animal hunters. So a team of researchers from Canada and U.S. analyzed how these animal predators "see" zebra stripes in various lighting conditions.
"The most longstanding hypothesis for zebra striping is crypsis, or camouflaging, but until now the question has always been framed through human eyes," said lead author Amanda Melin from the University of Calgary. Melin is a biological anthropology assistant professor.
The research team estimated the distances wherein spotted hyenas, lions and even zebras can distinguish zebra stripes in varying light conditions including twilight, daylight and moonless nights.
Zebra predators often hunt in woodlands and shrubs during moonless nights. In this scenario, the zebra stripes can only be distinguishable by feline eyes at 29 feet. At twilight, the stripes are only visible within 98 feet. The team said that in short distances, the big cats can locate their targets using their sense of smell and hearing. This makes any camouflage mechanism ineffective.
The team also found that in long distances, the zebras can't tell between solid and stripe patterns. This suggests that their unique coats don't serve a social function either. The paper was published in the journal PLOS ONE on Friday.
UC Davis wildlife biology professor and study co-author Tim Caro said the findings do not provide evidence or support to the theory that zebra stripes act as a form of anti-predator camouflage.
"Instead, we reject this long-standing hypothesis that was debated by Charles Darwin and Alfred Russell Wallace," added Caro.
The debate over zebra stripes' purpose started 120 years ago in the time of Charles Darwin, who dismissed the camouflage theory in a long-standing debate with Alfred Russel Wallace. Darwin proposed that the stripes served as a sexual selection tool.
Some scientists said the stripes help zebra visually confuse their predators while some said the pattern has body heat control abilities. There were also those who said the patterns help zebra recognize each other. This 2016, the age-old debate of whether zebra stripes are for camouflage finally came to rest.
Photo: Brieuc Saffré | Flickr
