Why do zebras have black and white stripes? A computer game has the answer

It is a mystery which has been the source of many a heated debate, flummoxing naturalists since Charles Darwin’s era: why does a zebra have black and white stripes?

Now, a new study has dismissed the popular theory that the animal’s impressive “dazzle” patterns are a defence against predators.

There have been many explanations for the zebra’s black and white stripes, but the most common has been the species makes use of the unusual camouflage pattern to avoid predators on the African plains. They even provided inspiration for the Royal Navy to use a zebra-inspired dazzle pattern to protect its ships from U-Boat attacks during the First World War.

However new research by academics at Cambridge University suggests the zebra’s stripes are unlikely to have come about as a method to protect the animal from hungry lions, leopards or cheetahs.

The study, in the journal Frontiers in Zoology, used 60 volunteers to play the part of predators in a computerised chase game and revealed that striped targets are actually easier to catch than plain- coloured prey.

According to study leader Dr Anna Hughes, who receives funding from the Ministry of Defence, the research won’t just be of interest to naturalists and designers of military camouflage. “This research could, after further study, be useful to road safety experts who want to get a better understanding of clutter and how the brain perceives road signs along the motorway,” she said.

Dr Hughes isn’t the first scientist to rule out the camouflage theory behind the zebra’s stripes. As long ago as 1871 Charles Darwin dismissed the idea they could act of camouflage, citing an observation by English explorer William Burchell that described how the “brightness and regularity of their stripped coats presented a picture of extraordinary beauty” and made the animals easier to spot.

Rather than aiming to conceal ships, dazzle paint schemes were intended to make it more difficult for an enemy submarine or aircraft to estimate a target’s range, speed and heading.

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In the Royal Navy and US Navy, competitions were held to create the best camouflage of geometric shapes and contrasting colours. However, by the mid-point of the Second World War the idea was generally out of favour.

In 1918, at the end of the First World War, the British Admiralty had attempted to analyse shipping losses to reach a verdict on the dazzle paint schemes, but was unable to draw any firm conclusions.