(Image source: Flickr/Woodlouse)

BY MALLORY PERRYMAN

ANCHOR MEGAN MURPHY

How do zebras get their stripes? There’s been plenty of theories thrown out there — but now some researchers say — they think it has to do with shooing away horseflies. Here’s WRC.

“Apparently the flies find the stripes unattractive because of the way they reflect light. The flies instead prefer dark coats. The study was published in the Journal of Experimental Biology.”

The researchers didn’t use real zebras for the study — instead — they painted objects either dark, light, or striped — put those objects in a horse-fly infested field — then used glue to trap any flies that landed. The Economist reports the results.

“Their first discovery was that stripes attracted fewer flies than solid, uniform colours. As intriguingly, though, they also found that the least attractive pattern of stripes was precisely those of the sort of width found on zebra hides.”

Animal experts have speculated about the secret to the stripes for more than a century. The original theory was that the stripes served as camouflage in tall grass. But in the 1870’s — Charles Darwin pointed out — zebras graze in short grass.

Since then — Animal Planet explains this story-of-the-stripes has been widely accepted.

“The black and white works because zebras always hang out in herds. Moving together in a group, their striped bodies create an optical illusion.”

So does the horsefly explanation debunk that theory? The researchers say more tests are needed — but they do have an answer to one nagging question — if black-and-white bars repel flies, why aren’t horses sporting stripes?

“...[The researchers think] the answer may be in the fact that there are more horseflies, and more horsefly species, in Africa compared to more temperate regions. Zebras would have been under more pressure to evolve a deterrent.”

Researchers say they need to do the experiment with real-life zebras — since a zebra’s breath or body heat could be responsible for fending off horseflies.