Anyone who has taken a bath, washed a lot of dishes or spent a good time in the pool has experienced the feeling of wrinkled fingers. However, few of them know the reason why this phenomenon occurs. It is popularly thought that water penetrates the skin, softening it in such a way that wrinkles 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 it may seem to us, the fingertips do not swell but rather contract, thus causing wrinkles.
A team of scientists from the University of Newcastle, located in the north of England, wanted to delve further into this question 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 an adaptation mechanism of the human being by which, when 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 in 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 water for a while, and therefore already with the skin of the wrinkled fingertips, 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, experts have reflected in depth on the meaning of this adaptation at an evolutionary level, inclining to think that wrinkled fingers allowed our ancestors to search for food in the water. In the case of toes, human evolution would bring about a different cause: it would help them to hold on to wet surfaces.
