Biology
Why Do Fingers Wrinkle in Water?
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Skin soaking up water is not the full story: a finger with nerve damage stays smooth. How the nervous system makes wrinkles, and why their purpose is still debated.
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Key points
- Fingers with nerve damage do not wrinkle normally, so wrinkling is not just water absorption.
- After a few minutes in water, the nervous system makes blood vessels in the fingertip narrow.
- Fingertip volume falls and the skin is pulled down into wrinkles.
- A 2013 study found wet objects were moved faster with wrinkled fingers (reported as about 12%).
- A 2014 study could not repeat this, so the purpose is still an open question.
What the two studies found
| Study | Result |
|---|---|
| Kareklas, Nettle & Smulders, 2013 | Wet objects moved faster with wrinkled fingers; no difference for dry objects |
| Haseleu et al., 2014 | Could not reproduce the benefit |
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