Wrinkled Fingers Enhance Grip of Wet Objects by 12 Percent

Wrinkled fingers and toes may have developed to improve ancient humankind's ability to collect underwater food, according to a study recently published in the journal Biology Letters.

Co-author Tom Smulders and his team at Newcastle University in England tested a sample group of people whose hands were wrinkled against a control group whose fingers were not, and gave them the task of moving wet objects. Smulders found that "wrinkled fingers give a better grip in wet conditions. It could be like treads on your car tires, which allow more of the tire to be in contact with the road and gives you a better grip."

More specifically, those with wrinkled fingers were able to grip wet objects twelve percent faster than those without. Notably, the researchers discovered that the same concept applied to toes as well. Fingers prune up when blood vessels in our hands constrict, which occurs after a few minutes in the water.  

"The actual origin of this may have been to help us move on all fours," says Smulders. "Going back in time, this wrinkling of our fingers in wet conditions could have helped with gathering food from wet vegetation or streams. And as we see the effect in our toes too, this may have been an advantage as it may have meant our ancestors were able to get a better footing in the rain."