The mystery of zebras with black and white stripes embedded on their skin was to repel biting insects, say researchers from the University of California.
Zebras’ monochrome markings evolved to repel biting insects, such as horseflies and tsetse flies, which usually avoid striped surfaces.
Applying it to modern lifestyle, they say wearing a similarly striped T-shirts should one day become the norm to repel mosquitoes but it requires to study the material suitable for its effectiveness.
|“A T-shirt may help somewhat but it might not be the whole story. Certainly if you are going to buy a T-shirt make sure the stripes are thin.,” Tim Caro, lead author and UC Davis professor of wildlife biology said.Don’t buy a striped jumper too quickly. Black and white striped surfaces reflect different sorts of visible light but they also reflect different sorts of polarised light which we can’t see but flies can.
The extent of polarised light reflected also depends on the nature of the surface – think of gloss and matte paint – and hairs probably reflect polarised light in different ways.
So it may be that the different hairs of the zebra’s pelt are important in preventing flies from landing on them.” – Prof Tim Caro, , lead author and UC Davis professor of wildlife biology.
Since the times of Alfred Russel Wallace and Charles Darwin, the subject was debated and explanations varied from a form of camouflage, assisting escape from predators by visually confusing them, to heat management.
But the latest study, published in the journal Nature Communications, that mapped the seven different species of zebras, horses and asses and their subspecies, has concluded that the thickness, location and intensity of their stripes on several parts of the body, avoided blood sucking flies.
“I was amazed by our results,” said Prof Caro. “Again and again, there was greater striping on areas of the body in those parts of the world where there was more annoyance from biting flies.”
However, Prof Caro says it is not yet known why biting flies avoid striped surfaces. “Some ideas include lateral inhibition but these are not researched as yet.”