Hold on to that paddle. Photo: Shutterstock
Scientists previously thought that the smooth, hairless surfaces of fingers and toes wrinkled up like raisins after they got wet because water passed into the outermost layer of skin, causing it to swell. But recent studies have shown that the wrinkling is not a result of osmosis, but rather an autonomic nervous system reaction: placing hands or feet in water causes a constriction in blood vessels which reduces the pulp in digits. The loss of internal pressure causes ridges and valleys to form on glabrous skin. The question, of course, is why?
A new study published by three scientists in the journal Biology Letters suggests the physical change may have developed as a way to improve grip on wet objects. In other words, prune-like fingers and toes that form during long surfing and kayaking sessions may actually help you hold on to your board or paddle.