UPDATE: 2012-01-09 Researchers at my alma mater, Newcastle University, have today published experimental evidence that supports Changizi’s theory. According to a report from Nature news: “Laboratory tests [by Tom Smulders et al published in Biol Lett] confirmed a theory that wrinkly fingers improve our grip on wet or submerged objects, working to channel away the water like the rain treads in car tyres.”
The real reason for pruney fingers – Sit in a bath too long and your fingers will wrinkle up. Everyone from 5 to 95 knows that. The scientific explanation was always that the skin absorbs water and the underlying layer buckles. That’s as may be, but writing in Nature News, Ed Yong explains an explanation from Mark Changizi and colleagues that suggests pruney fingers have an evolutionary advantage in that they allow us to get a grip when we’ve been in the water.
Changizi, an evolutionary neurobiologist at 2AI Labs in Boise, Idaho, and his colleagues think that the formation of wrinkles on the pads of our fingers when we swim or bathe act like tyre treads in wet conditions expelling water when conditions are slippery. It’s possible, just don’t rely on a theory to save your glass if you enjoy long soaks champagne in hand.