Why fingers shrivel in the water?

Anyone who has taken a bath, washed a lot of dishes or spent a good time in the pool has experienced the feeling of having wrinkled fingers. However, few of them know the reason why this phenomenon occurs. It is popularly thought that the water enters the skin softening it in such a way that it causes wrinkles to form on its surface, something that also occurs on the toes.

But this explanation is not entirely true. What happens is that during prolonged contact with water, the blood cells under the skin shrink in response to an impulse from the autonomic nervous system. Therefore, contrary to what may seem, the fingertips do not swell but contract, thus causing wrinkles.

A team of scientists from the University of Newcastle, located in the north of England, wanted to delve deeper into this issue and found a solution that, according to them, would explain much better the true causes underlying this phenomenon. These causes would not be other than that of a human adaptation mechanism by which, by being in contact for a long time with water, the skin of our fingers would wrinkle to allow us to better grip wet objects.

An experiment with marbles

To demonstrate the suitability of their thesis, the scientists asked 20 participants of an experiment to move a few marbles, both wet and dry, from one container to another through narrow openings. The result was that if this process was carried out after having had the fingers under the water for a while, and therefore with the skin of the wrinkled buds, the handling of the marbles was much more skillful and successful than when this process was done with dry fingers.

As a result of these results, the experts have reflected in depth on the meaning of this adaptation at the evolutionary level, inclining to think that the wrinkled fingers allowed our ancestors to look for food in the water. In the case of the toes, human evolution would lead to a different cause: it would help them to grab onto wet surfaces.