A Simple Explanation of Why Our Fingers and Toes Wrinkle in Water

SciShow host Michael Aranda explains why the skin of our fingers and toes wrinkle after being in water for an extended period in their most recent video. He describes how the cause is not the skin absorbing water, but instead the cause is an involuntary nerve response that constricts blood vessels, puckering the skin above. A possible evolutionary reason for this response is that wrinkled skin on fingers and toes make grabbing and holding wet things a little easier.