MINNEAPOLIS (WCCO) — Spend 15 minutes in pool, a bath or washing dishes and your fingers and toes look like prunes.
That has Emily from Arden Hills wanting to know: Why do they get wrinkly in the water? Good Question.
It used to be that people thought fingers and toes swelled up with water. The theory was the outer most layer of skin would absorb the extra water, but the layer underneath would not. Given those two layers of skin are tightly connected, the top layer would wrinkle. It was kind of like having a king-sized sheet on a queen matress.
But, in 2010, some cognition researchers suggested that the waterlogged theory might not be the whole story.
For decades, researchers have known the wrinkling phenomenon doesn’t happen to people with nerve damage in their fingers.
So, Mark Changizi, director of human cognition at 2AI, wondered why. His theory, along with fellow researchers, was based in evolution. They suggested these wrinkles are like the treads found in tires or shoes and would allow people who are wet to grip objects more effectively.
That research suggests the nervous system causes the wrinkly by constricting the blood vessels below the skin, which makes the upper levels of skin pucker up. That could make it easier to walk in the rain or gather food when it’s wet.
“Far from an embarrassing mistake, wet wrinkled fingers are yet another testament to biology’s brilliance,” wrote in a 2011 Forbes article explaining his research.