Hey, and welcome to the podcast. I'm Josh, and Chuck's here and Jerry's sitting in for Daves, and that makes this a short. Do you want to take it from here?
Sure? I had this idea because of a story I'm going to very quickly tell that may make people think I'm a terrible parent. But my daughter the other day was in the bathtub for seven plus hours.
What what'd she do? And does she read or play video games or.
She's always like long baths. She just kicks it and plays with her little action figures, her cuckoos, and she's always just done voices and little made up worlds and just sometimes it's music. Sometimes it's her favorite podcast, story Pirates. But the other day she got in early in the morning.
It was a Saturday. She didn't eney anything going on, and she just stayed and stayed, And then I think was playing it up because I kept going in there every hour and saying a new household record, and then I would say the time, and she just thought it
was hysterical. So she came out. I'm going to text you actually right now the picture of her hand, okay, And I've never seen anything like it, and it made me think, like, you know what, I don't even really know why people's hands and feet prune up anyway, and that's where this was born.
What a fantastic story, What a great origin story for this.
Do you have your phone?
I do? Lay it on me all right?
I sent it to you. It's incredible. You know, I'll post this on my Instagram Chuck the podcaster when this comes out, because people should see. God, isn't that amazing?
Wow? She looks like Benjamin Button after he was first born.
Yeah, it's really something that is amazing.
I'll bet you were like, how does this happen?
Well, the first thing I looked up was like, have I done something really wrong? It's this danger and it is not. You can sit in the water like that and it's all fine and good and your handsle and feet will go back to normal soon enough.
That's awesome. I've done something wrong. Yes, it's gonna be like that forever. So okay, there's a great question. This is a tailor made short stuff, Chuck, Like, what makes your skin prune up when it's submerged in the water. And it's not just any part of your skin, it's specifically your hands and your feet, and in particular your fingertips and toes that really get pruney at least first. And the answer is, we're not one hundred percent sure
why that happens. There's some good guesses, but science seems to have gotten to the bottom of how it happens.
Yeah, it was for a long time, I think, up until like the early twentieth century, science basically thought it was osmosis. So you know, the movement of water from one place to another, in this case from the outer layers the drier outer layers of the skin retreats essentially, and so your skin and hands are expands that surface area and it just gets wrinkly. But then they were like, wait a minute, that's not the case.
No, because somebody figured out in the nineteen thirties that if you have nerve damage on your fingertips, you can soak and palm olive till the cows come home and you're not going to get pruny fingers. So like, that doesn't make any sense, Like if it's just osmosis, like it should happen to anybody with skin in water, that's
just how that works. So they're like, since it's nerve damage, that makes us think that there's some sort of maybe autonomic nervous system control going on, And it turns out that's exactly what it is. And the original scientists who thought that it was it wrinkled from your skin puffing up. We're kind of looking at it backwards, and it turns out your skin is actually shrinking it when it gets all pruney from being in the water.
Yeah, it's vaso constriction. So your blood vessels under the epidermis are shrinking, and it's just a response to water. When you put something in water for your skin that is in water too long, the nervous system is going to restrict that blood flow automatically. It's a pro like you said, the autonomic system which controls perspiration and breathing and the things we don't need to think about, and
this is just another one. You lose that volume in each little fingertip and they shrink inward and it looks pruney.
Yeah, so rather than puffing out paying attention to those ridges, you wanted to look at the valleys. That's the key the valley.
Yeah.
The science finally figure that out, and apparently they've known it for decades. I didn't know what it was until just now. So thanks for that, and I say we take a break because it's kind of like the wild Wild West, just a total free frawll in explaining why that happens. So check. There's a bunch of different theories about why our fingers proved, because if you think about it, it doesn't really make sense if it's not osmosis and it's just like a passive response to being in water.
But our actual nervous system is doing this. Why is there an evolutionary advantage to it? Because think about it, it takes energy to do that, and over time that would suggest that natural selection selected for that trait in humans. And it turns out, yeah, that's right.
Weirdly, and this is the theory that I think a lot of scientists have gotten behind and they say they've I'm not sure if they can say they've really really proved it, but they have done some studies that sort of indicate that it may be true. But there was a guy in twenty eleven named Mark Changeeze, and Mark Changheze said, hey, I got a little theory on why
skin prunes if you want to hear it. Actually he was an evolutionary neurobiologist, so he probably didn't talk like that, but he was in Boise, Idaho, and he and his colleague said, what we think is going on is that it is an evolutionary adaptation that is a benefit to us, and that is it makes us able to grip things better when our hands or the thing or both are wet.
Right, And everybody else went prove it, and some other people did. I think a UK group from New Kestle Diversity actually took that theory and put it to the test, and they found out that if you pick up wet or dry objects, marbles specifically of varying sizes, if your fingers are pruney, you are twelve percent faster at picking up wet marbles than somebody whose fingers aren't pruney or just plump and dry like normal. Yeah, that's significant, that's
a that's a big difference, twelve percent faster. I tried to give an example or figure out an example. I can't, but just accept that that's actually a pretty pretty it's a reasonable difference that suggests like, no, there's an actual like ad this is an adaptation, right, And the way that it's kind of described is that like our fingers turned into tire tread in wet conditions. Almost.
Yeah, that's a perfect way to describe it. The way that one of the biologists at Newcastle explained it is completely incorrect, which bothers me. Yeah, because he said, we've shown that they give better grip and wet conditions. True, it could be working like treads on your car tires. True, This is the part that's not right, he says, which allows more of the tire to be in contact with
the road and gives you a better grip. Not true at all, because while he may know a lot about brain stuff, this guy didn't know nothing about car racing.
No, he just knows he likes to riding cars.
Yeah, because you know, race cars have slicks on them because you have one hundred percent contact with the road and much better grip. Treads actually give you less grip. The reason you have treads is to so the water spills on a wet road spills between the treads like a little valley, and that's the same thing that's happening here.
Yeah, channels water through it. So that Yeah, so you actually do have less contact but better traction.
Yeah. So aside from that, I think like standing ovation for me on this theory and proving it with a game of marbles.
I cannot agree with you on that.
Oh yeah, what do you think, buddy?
I have a question, That's what I think. I have a question.
Uh huh?
Does it have to have a function? Can it just be a consequence of the fact that we have evolved to send our hot blood toward the core when we're submerged in water to keep us alive, to keep the important bits alive, which means that the blood flows away from our extremities, like our fingertips, and because of that, our fingertips just kind of shrink, like they're saying, like
it's vasco constriction. Does it Does it have to have a reason evolutionarily or can it just be a consequence of that a byproduct that doesn't make any sense, or it just so happens it gives us better grip, or we have better grip when our fingers are crooney?
Well, I mean, is that a question you could ask about any evolutionary advantage is like did that just happen and it was coincidence that it turned out to be good for our survival?
No? Because I mean, let's say flying flight and burn right. Even if that did just happen to evolve as an accident or a consequence of something else, which I don't think it did. It was so quickly and so thoroughly selected that they think that flight occurred. It like evolves separately in different areas of the world at different times. It's just that it's just that advantageous. This is not particularly advantageous, and it's possible humans are just reading more
deeply into something. I know, you know what I was saying. I'm essentially just restating my case here.
I would argue that it is, and they argue that it is advantageous because Tuktook in the rain is able to gather more twelve percent more in fact wet berries then he would have had he not had that wrinkled skin, and also potentially better attraction on slippy rock surfaces with those pruny toes, and so TikTok isn't falling and hitting his little head.
Okay, it's mister smart guy. Why if it's just so advantageous to have, why aren't our fingers puney all the time? Yeah?
Well, I know you're being coy because I have no idea. But they did ask those scientists that same question, and they said that it's not too clear, but their initial thought was here's the quote. Our initial thoughts are that this is that this could diminish the sensitivity in our fingertips or could increase the risk of damage through catching on objects. So skin goes back to smooth fingertips when it's not needed, because that, you know, isn't so great to have full time.
Okay, that's a reasonable explanation to that one. Yeah, so I guess well, I'm not going to say that the case is subtled because I just don't agree.
Hey man, I respect your opinion, and you know what, I don't really have one one way or the other. I just think it's interesting.
All right, that's great. Well everybody chucks that, hey man, which means short stuff is that.
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