The Mystery of Wrinkled Fingers
Do wet fingers wrinkle the same way every time? One scientist set out to find the answer.
Courtesy of Guy German/Binghamton University, State University of New York
Photo A shows how a person’s finger wrinkled after getting soaked. Photo B shows the same person’s finger after it was soaked again 24 hours later.
Kids have lots of questions, but it’s not every day that a kid’s question leads to a scientific discovery.
Guy German, a professor of biomedical engineering at Binghamton University, wrote an article explaining why our fingers get wrinkly during a long bath. The answer has to do with our blood vessels, the narrow tubes that carry blood to all parts of our bodies, including our fingers. When our fingers have been soaking for long enough, our skin absorbs water. The water decreases the amount of salt in our skin. When our salt levels are lower, our brains respond by constricting, or squeezing, our blood vessels. With our blood vessels even narrower, the skin around them folds inward, or wrinkles.
German’s article was written as part of a series that invites kids to send in their questions so that a scientist can answer them. After the article was published, German received a follow-up question from a young reader. The reader wanted to know if a person’s skin wrinkles in the same pattern every time it gets soaked. German didn’t have the answer, so he did what he knows how to do: He set up an experiment.
German and one of his students asked three people to soak their hands in water for 30 minutes. They then took photos of the pattern of wrinkles on each person’s fingers. The three people came back and did the same thing 24 hours later. It turns out, each person’s wrinkle pattern was the same.
Courtesy of Guy German/Binghamton University, State University of New York
Photo A shows a finger before it got wet, and Photo B shows the same finger after it got wet. Photo C shows the same finger after it got wet again 24 hours later.
The scientists believe that a person’s wrinkle pattern will be the same every time they get soaked. German says this is because the location of our blood vessels influences where the wrinkles form, and our blood vessels don’t move very much.
German wants to learn more about how water affects the skin. Next, he wants to find out if the pattern of wrinkles stays the same all our lives or if it changes as we get older.
“I feel like a kid in a candy store, because there’s so much science here that I don’t know,” German told Binghamton University.
Courtesy of Jonathan Cohen/Binghamton University, State University of New York
Guy German is the scientist who led the experiments on finger wrinkling.
