Fingers wrinkle same way each time when immersed in water: Study

The wrinkled, raisin-like patterns on fingers after being immersed in water form the same patterns every time, according to a study published in Journal of the Mechanical Behavior of Biomedical Materials. The researchers found that blood vessels under the skin contract during immersion but stay in place, causing the skin to wrinkle consistently in the same pattern with each exposure.