Zebra Stripes Do Not Help When It Comes To Evading Predators

Despite what most people think, zebra stripes do not help them evade predators. According to a new study their distinctive pattern may even make them easier to catch instead of making it harder. The research debunks the theory that zebra stripes offer what is known as motion dazzle which is thought to have evolved in animals like zebras and was even used to camouflage ships during the two World Wars.

Human trials

The study consisted of people playing a computer game in which they were required to capture targets. It was found that humans were able to capture striped targets more easily than grey targets when there were several targets present. This contradicts previous assumptions about the evolution of stripes when it was thought that stripes made it harder to capture a single animal moving in a group like zebras.

Stripes make animals more conspicuous

Stripes and other contrast markings make animals very conspicuous which one would expect would make them much more visible to stalking predators. It is argued that perhaps movement is the reason for the evolution of such patterns. The thinking is that contrast markings may help to confuse predators which limits the likelihood of being captured and killed. This concept is known as ‘motion dazzle’.

Horizontal stripes the easiest to capture

The study involved 60 human participants, each of whom played a game to test how much stripes influenced their perception of moving targets. The game required the participants to ‘catch’ moving targets that appeared on a touch screen in two scenarios. The first was when there was only a single target on the screen and the second scenario was when there were several targets that appeared simultaneously. It was found that horizontal striped single targets were present, they were easier to capture than any other type of target. When multiple targets were presented, any target with a stripe regardless of its orientation was much more easily captured than uniform grey targets

“Motion may just be one aspect in a larger picture. Different orientations of stripe patterning may have evolved for different purposes. The evolution of pattern types is complex, for which there isn’t one over-ruling factor, but a multitude of possibilities,” said Anna Hughes of the University of Cambridge who led the study.