Wrinkling fingers - breaking news

Cecil's Columns/Staff Reports
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Regarding the column on fingers and toes pruning when wet: Why do your fingers and toes wrinkle in the bathtub? - The Straight Dope (just reposted on the front page today.)

There’s some thinking now that it’s actually an adaptive mechanism to help get better grip in wet conditions, like water-channeling treads on a tire: http://www.nature.com/news/2011/110628/full/news.2011.388.html. A major piece of evidence is that fingers with nerve damage do not wrinkle, showing that it’s under the body’s control, and not just a by-product of how skin is made.

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Wow! I’ve been wondering for ages whether there was any biological advantage conveyed by skin doing that.

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So it is akin to goosebumps … hmmm. That would explain why you do not get prune skin other than on the extremities.

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Except, of course, that as Unca Cece notes, you DO get prune skin elsewhere, if you immerse it long enough.

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When skin"…buckles like asphalt on the highway in the summer sun…"

Wow, talk about poetry!! You kiddin me? Sounds like a line taken right out of a movie or a novel …er sumpin… anyone?

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Welcome to the Straight Dope Message Boards, CruznEden, we’re glad to have you here. When you start a thread, it’s helpful to other readers if you provide a link to the column you are discussing. Keeps us all on the same page, and saves search time. In this case, http://www.straightdope.com/columns/read/539/why-do-your-fingers-and-toes-wrinkle-in-the-bathtub …

No biggie, you’ll know for next time. And, as I say, welcome!

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There was another thread on the same column recently that had an additional interesting tidbit.

(Note to mods: If you decide to merge the two threads, feel free to delete this post, just to keep it simple.)

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Merged.

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But the fact that you do have to immerse other skin much, much longer would suggest that there’s an additional mechanism in the fingers and toes, wouldn’t it? I mean, water is still a hypotonic solution, and still going to permeate a permeable membrane like skin and cause some swelling, but the fingers do it so comparatively quickly…

In fact, I was just noticing yesterday while helping my daughter shampoo her hair (she can’t pour the shampoo from the bottle and catch it at the same time yet), that my fingers were wrinkly even though I was only touching the water for probably 2 minutes. Not very long at all - and certainly not close to “immersed”, as I was standing outside the shower reaching in.

All that, and especially the note that people with nerve damage don’t get wrinkly fingers…that’s some serious suggestion that it’s not just about osmosis.