Washington, Aug 9 (IANS) Hundreds of insects remain underwater. But how do they manage to breathe? A University of Alberta has found they create tiny air bubbles around them. The rough, waxy surfaces of insects and spiders are water-repellent. In some species, water-repellence is so pronounced that creatures may survive underwater for indefinite periods.

This is achieved by an air bubble called a plastron that the insect traps between its body and its hairs, creating an external lung. This lung facilitates oxygen and carbon dioxide exchange with the surrounding water. “The closer together the hairs, the more pressure the bubble can withstand before collapsing,” Flynn says.

Morris Flynn and colleagues at MIT, Massachusetts, found these insects cannot survive in deep waters where the pressure ruptures the bubble, nor can they survive in shallow waters where the bubble surface area is too small.

“We were surprised by the fact that, in some cases, bugs may be unable to survive in shallow water. But we did discover they can safely dive as deep as 30 metres.”

Flynn did this research while he was at MIT in Massachusetts. He is now continuing his work in the department of mechanical engineering at the University of Alberta.