We still don’t know why zebras have stripes
A fondly held theory that zebras evolved their black and white stripes to stay cool under the African sun has been debunked by new research.
It was thought the heat-retaining black stripes of the animal got warmer than the white areas, creating small vortexes when the hotter air above the dark fur met the adjacent cool air.
Other prominent explanations claim the zebra fur thwarts attacks from biting flies, that the stripes help protect the animal from predators by visually confusing them, or that they are the result of natural “sex selection”.
A team at Lund University in Sweden set out to discover if the heat theory translated to the real world by filling large metal barrels with water and then covering them with the skins of horses, cattle and zebra with various black, white and grey striped patterns.
The barrels were placed in the sunshine and the water temperatures measured. The black barrel became the hottest and the white barrel the coolest. The striped barrel and a grey barrel of equivalent overall whiteness reached similar levels. The study in Scientific Reports found no significant core temperature differences between the striped and grey barrels.