Why do your fingers wrinkle in water?

They wrinkle after about 5 minutes in water due to constriction of the blood vessels- pulling the skin inward.

In 2011, a study showed that the wrinkles form channels that divert water away from the fingertips. A team in Newcastle thought this might aid grip; they deduced that with wrinkles wet objects were moved 12% faster than with unwrinkled fingers.

It is suggested that our fingers aren't always like this as the wrinkles would affect the sensitivity of the fingertips- due to reduced surface area that touches the object.

Interesting, huh?