Our wrinkled fingers after staying too long in water forms a repetitive model, unique to each individual, shows a new study published in the Journal of the Mechanical Behavior of Biomedical Materials.
Temporary wrinkles provide a real biological advantage. Photo: X / @mayocinic
The author of the article-Biomedical engineer Guy German at Binghamton University, New York-and his colleague, Rachel Laytin, asked three volunteers to soften their fingers in water for 30 minutes. Photos taken then and 24 hours later showed that the models of “Grows and valleys” Formed by wrinkles, they were repeatedly repeated, it is shown in the study quoted by Science Alert.
This phenomenon is not caused by swelling, as previously believed. In fact, when the water penetrates through the open sweat glands, it reduces the concentration of skin salt. Nervous fibers detect the change and send a signal to the brain, which automatically triggers the blood vessels from the leather. Thus, the surface of the skin tightens and the characteristic wrinkles appear.
“The blood vessels do not change their position too much-they move a little, but in relation to the others they are quite stable,” explained the author of the study. “This means that wrinkles also appear in a similar way, and we have shown this.”
Interestingly, these temporary wrinkles offer a real biological advantage-they improve adhesion in wet environments, helping us to grab wet objects or to walk on slippery surfaces. However, researchers do not yet know why the skin does not keep this texture permanently. It is suspected of reducing tactile sensitivity or increasing the risk of injury.
Another fascinating detail: people with median nerve lesions do not develop wrinkles at prolonged exposure to water. A student by Guy German, who suffers from such injuries, was tested and did not present wrinkles on his fingers.
This discovery not only meets scientific curiosities, but can have practical applications, for example, in forensic medicine – in identifying corpses after prolonged exposure to water, as in the case of natural disasters.
The unique model of these temporary wrinkles thus completes the set of “Signatures” Personal of human skin, along with digital fingerprints and invisible stripes we all have.
