WEBVTT - What are the Most Incredible Things the Human Body can do? 0:00:00.200 --> 0:00:02.640 Guess what, mango, what's that? Well, all right, So the 0:00:02.640 --> 0:00:05.360 other day I was driving past Turner Field here in Atlanta. 0:00:05.440 --> 0:00:07.680 You know, that's the stadium where the Braves used to play, 0:00:07.720 --> 0:00:10.240 but it was originally built to serve as the Olympic 0:00:10.280 --> 0:00:12.840 stadium back in the nine Olympics that were here. You know, 0:00:12.960 --> 0:00:15.040 I've actually forgotten that was the reason it was built. Yeah, 0:00:15.080 --> 0:00:16.480 and I was thinking about the first time I had 0:00:16.480 --> 0:00:18.880 ever stepped foot in that stadium. I was in high 0:00:18.880 --> 0:00:20.680 school at the time, and my family had made the 0:00:20.680 --> 0:00:23.479 trip over from Birmingham to watch some Olympic track and 0:00:23.560 --> 0:00:26.799 field and it is an experience I will never forget. 0:00:27.240 --> 0:00:29.720 That was the year Michael Johnson and those bright yellow 0:00:29.760 --> 0:00:33.680 shoes just destroyed the competition and pretty much every race 0:00:33.760 --> 0:00:36.800 he ran. You remember this. I definitely remember watching him 0:00:36.800 --> 0:00:38.280 in a few of the heats leading up to his 0:00:38.360 --> 0:00:41.599 gold medal races and seeing some of the best athletes 0:00:41.600 --> 0:00:44.479 in the world honestly just look like children, as he 0:00:44.560 --> 0:00:47.559 was just that much better than everybody else. Yeah, he 0:00:47.640 --> 0:00:50.199 was incredible. I remember watching him from home. Well, I 0:00:50.240 --> 0:00:53.560 remember thinking, how could somebody's body be that much better 0:00:53.760 --> 0:00:56.320 at doing what it was doing than every other runner 0:00:56.360 --> 0:00:57.880 out there and these are some of the best in 0:00:57.920 --> 0:01:00.560 the world. It was just wild. But as we've done 0:01:00.560 --> 0:01:03.280 our research in recent weeks, we've realized that all human 0:01:03.320 --> 0:01:06.720 bodies do some pretty incredible things. So today we're going 0:01:06.760 --> 0:01:08.839 to talk about some of the most incredible and weird 0:01:08.959 --> 0:01:12.280 things our bodies do. And Michael Johnson, if you're listening, 0:01:12.520 --> 0:01:15.640 and I'm sure he is, definitely, it's time you knew 0:01:15.680 --> 0:01:28.479 that we're pretty special too. So let's get started, right 0:01:39.640 --> 0:01:42.360 he their podcast listeners, Welcome to Part Time Genius. I'm 0:01:42.360 --> 0:01:44.280 Will Pearson and as always I'm joined by my good 0:01:44.280 --> 0:01:46.679 friend man Guesh Ticketer on the other side of the 0:01:46.720 --> 0:01:50.000 soundproof glass doing that weird thing where you like waves 0:01:50.080 --> 0:01:52.200 with his ear. It's not like a twitch. How does 0:01:52.200 --> 0:01:55.480 he do that? It's like wave? It is so strange. 0:01:55.480 --> 0:01:57.480 So but we're talking about things we do with our bodies, 0:01:57.520 --> 0:02:00.720 and so that's appropriate. That's our friend and producer Ustan McNeil. 0:02:01.360 --> 0:02:03.320 So today we're taking a long, hard look in the 0:02:03.320 --> 0:02:05.800 mirror to find out just how weird the human body 0:02:05.880 --> 0:02:07.920 really is. You know, we tend to think of our 0:02:07.960 --> 0:02:11.040 brains as being the most remarkable and defining features of 0:02:11.040 --> 0:02:13.920 our species. And you know, for good reason. But the 0:02:14.000 --> 0:02:16.040 human body is no slouch when it comes to these 0:02:16.120 --> 0:02:19.720 unusual qualities either. So with our own weirdness in mind, 0:02:19.760 --> 0:02:22.200 we thought it'd be fun to take this anatomical tour 0:02:22.400 --> 0:02:26.400 of our most peculiar physical abilities. Yeah, and along the way, 0:02:26.440 --> 0:02:28.320 we'll try to figure out what our bodies are actually 0:02:28.320 --> 0:02:30.399 made of, as well as what happens to them once 0:02:30.400 --> 0:02:32.760 we kick the bucket. All right, So I thought we 0:02:32.800 --> 0:02:35.600 could start by looking at the building blocks of our bodies, 0:02:35.639 --> 0:02:37.720 you know, which are of course these hundreds of different 0:02:37.760 --> 0:02:40.160 types of cells that make us up. And I think 0:02:40.200 --> 0:02:42.360 it'll be a good refresher because you know, we usually 0:02:42.440 --> 0:02:44.920 take our body at face value and kind of think 0:02:44.919 --> 0:02:48.520 of it as this one continuous thing rather than maybe, 0:02:48.680 --> 0:02:52.240 I don't know, like this composite mass of microscopic tissue 0:02:52.240 --> 0:02:54.519 blobs that it it really is. I mean, I feel 0:02:54.560 --> 0:02:56.720 like we're always hearing about these building blocks, But how 0:02:56.720 --> 0:02:58.800 many does actually take to build a complete person? Do 0:02:58.800 --> 0:03:00.760 you know? Well, as you i'd expect that it's not 0:03:00.800 --> 0:03:02.960 the easiest thing in the world to calculate. So I 0:03:03.000 --> 0:03:04.959 was looking into it, though, And the best guest comes 0:03:04.960 --> 0:03:07.160 from a group of researchers who actually broke down the 0:03:07.240 --> 0:03:10.080 number of cells in the human body according to organs 0:03:10.080 --> 0:03:13.160 and cell types. So, for example, the average body contains 0:03:13.200 --> 0:03:17.000 about fifty billion fat cells, two and forty billion liver cells, 0:03:17.040 --> 0:03:19.519 and so on, And when you add up all these 0:03:19.560 --> 0:03:22.959 different cell counts, the total comes to an astounding thirty 0:03:23.080 --> 0:03:27.280 seven point two trillion cells. It's unbelievable. That's a lot 0:03:27.320 --> 0:03:31.040 of trillion cells. But it's actually insane to think that 0:03:31.040 --> 0:03:33.720 that many cells can get along and like function in 0:03:33.760 --> 0:03:36.800 a single human body. And they do it for decades. 0:03:37.360 --> 0:03:39.840 But aside from having this impressive figure to throw around, 0:03:39.920 --> 0:03:42.000 is there any real benefit to knowing how many cells 0:03:42.040 --> 0:03:44.800 compose the body? Well, there actually is, you know, according 0:03:44.800 --> 0:03:47.440 to the authors of the study quote, knowing the total 0:03:47.480 --> 0:03:50.000 cell number of the human body, as well as the 0:03:50.080 --> 0:03:54.520 individual organs is important from a cultural, biological, medical, and 0:03:54.560 --> 0:03:58.040 comparative modeling point of view. So imagine a doctor who 0:03:58.080 --> 0:04:01.000 measures a patient's liver cell and they find that it's, 0:04:01.040 --> 0:04:03.720 you know, maybe way below average. Well, that kind of 0:04:03.760 --> 0:04:07.160 quick comparison makes it easier to identify potential health problems 0:04:07.240 --> 0:04:10.000 earlier on, and that's pretty cool. And obviously cells carry 0:04:10.000 --> 0:04:12.480 out all kinds of vital functions that go overlooked. But 0:04:12.920 --> 0:04:15.320 they also have this other impact on our bodies that's 0:04:15.320 --> 0:04:17.440 even easier to miss. Have you ever heard of the 0:04:17.440 --> 0:04:19.840 blatch Co lines? No, I can't say that have So 0:04:20.080 --> 0:04:23.160 it's actually the term for this swirling pattern of invisible 0:04:23.160 --> 0:04:25.719 stripes that covers the human body from head to toe. 0:04:26.040 --> 0:04:29.960 Invisible stripes. I'm pretty sure you're making this one up. No, 0:04:30.200 --> 0:04:32.280 it's true. So one of the first people to notice 0:04:32.320 --> 0:04:35.479 them was this German dermatologist named Alfred Blatchko, which is 0:04:35.480 --> 0:04:38.400 where the name comes from. But in the early nine hundreds, 0:04:38.400 --> 0:04:41.320 he observed similarities and patterns of many of his patients 0:04:41.440 --> 0:04:44.240 rashes and blemishes, and it was almost like these formations 0:04:44.240 --> 0:04:47.120 were following these invisible lines on the skin, but the 0:04:47.160 --> 0:04:51.080 paths didn't exactly coincide with underlying nerves or blood vessels. 0:04:51.400 --> 0:04:54.119 And the truth about the lines wasn't discovered until way later. 0:04:54.320 --> 0:04:56.920 But we now know that they're actually the lingering signs 0:04:56.920 --> 0:05:01.520 of our cellular development. And how's that. Well, we may 0:05:01.600 --> 0:05:06.680 have what was a thirty seven trillion cells, you said, yeah, 0:05:06.720 --> 0:05:09.160 but each of us just started as one and then 0:05:09.160 --> 0:05:12.039 this is a single cells zygote then divided into a 0:05:12.120 --> 0:05:15.000 small bundle of cells. And from there the cells divide 0:05:15.040 --> 0:05:18.800 again and again, you know, sometimes differentiating into specialized cells. 0:05:19.080 --> 0:05:21.520 What ones that would form are various muscles or bones 0:05:21.560 --> 0:05:25.120 and organs. But skin cells, like, they're scarcer than other 0:05:25.200 --> 0:05:27.880 kinds of cells, and they have to stretch and expand 0:05:27.960 --> 0:05:30.600 as they divide in order to cover our fast growing bodies. 0:05:31.000 --> 0:05:34.120 And when this happened, lines of different cells begin to intersect, 0:05:34.279 --> 0:05:37.280 knocking into each other and creating molecular swirls in our skin. 0:05:37.720 --> 0:05:40.320 And so does this happen all over our bodies? And 0:05:40.320 --> 0:05:42.800 and why can't we see these? Yeah? So these lines 0:05:42.839 --> 0:05:45.360 are everywhere, you know, They're up and down your arms 0:05:45.400 --> 0:05:49.080 and legs and around your head and torso too. I mean, 0:05:49.120 --> 0:05:50.839 the reason we don't see them is that all of 0:05:50.839 --> 0:05:54.000 our cells tend to carry the same DNA instructions on 0:05:54.040 --> 0:05:56.520 how much pigment to use in our skin. So these 0:05:56.560 --> 0:05:59.080 subtle differences in the color between the lines of skin 0:05:59.120 --> 0:06:02.080 cells are there, but they're really hard for us to 0:06:02.120 --> 0:06:05.640 see unless you're checking for them under UV light. That said, 0:06:05.640 --> 0:06:07.920 there are people with certain skin conditions that cause these 0:06:07.920 --> 0:06:10.320 stripes to be visible to the naked eye, and This 0:06:10.360 --> 0:06:13.159 is because there are skin cells actually disagreed about which 0:06:13.160 --> 0:06:15.760 color to make the skin, with some saying they should 0:06:15.800 --> 0:06:19.160 make it lighter, others making it darker. It's so interesting. 0:06:19.240 --> 0:06:21.600 That's bizarre. I mean, I mean, our bodies shed about 0:06:21.600 --> 0:06:24.640 a pound and a half of skin every year, which 0:06:24.640 --> 0:06:27.360 means that our surface skin cells are replaced every couple 0:06:27.360 --> 0:06:30.320 of weeks. So given that quick turnaround, it's pretty wild 0:06:30.320 --> 0:06:32.520 to think that we're also just wrapped in these invisible 0:06:32.640 --> 0:06:34.400 lines that you know, kind of date back to the 0:06:34.520 --> 0:06:36.840 dawn of skin. I know, it's it's really weird to 0:06:36.839 --> 0:06:39.800 think about, but honestly, the whole body is this mishmash 0:06:39.839 --> 0:06:42.920 of cells of all different ages, Like you know, the 0:06:43.279 --> 0:06:46.479 lining of our stomachs and intestines. We literally burned through 0:06:46.520 --> 0:06:48.880 those cells every few days because of all the bile 0:06:48.960 --> 0:06:51.520 and acids that we use to digest our foods. And 0:06:51.600 --> 0:06:54.440 we're just really lucky that replacement cells are always at 0:06:54.480 --> 0:06:57.680 the ready, or else we'd be digesting our own stomachs too. 0:06:58.120 --> 0:07:00.560 And some cells do stick around longer than others, like 0:07:00.760 --> 0:07:03.440 red blood cells have I think it's a four month 0:07:03.480 --> 0:07:06.000 lifespan before new ones are produced to take their place. 0:07:06.320 --> 0:07:08.800 But given a long enough timeline, just about every part 0:07:08.839 --> 0:07:11.480 of the human body is replaced like this. Yeah, you know, 0:07:11.720 --> 0:07:14.400 I mean it's sort of eerie how influx our bodies 0:07:14.440 --> 0:07:18.320 are constantly undergoing this cycle of cellular death and birth. 0:07:18.400 --> 0:07:21.040 And it actually makes me think about that ancient Greek 0:07:21.080 --> 0:07:24.240 thought experiment about the Ship of Theseus. You remember this, right, 0:07:24.360 --> 0:07:26.920 We've talked about a little bit before, But the story 0:07:26.960 --> 0:07:29.840 goes that Athenians preserved the ship of Theseus, who was 0:07:29.920 --> 0:07:33.600 the mythical king and founder of Athens, after he passed away, 0:07:33.640 --> 0:07:36.080 but his time went on, they had to gradually replace 0:07:36.120 --> 0:07:39.560 the ship's rotting wooden planks, and finally no piece of 0:07:39.600 --> 0:07:42.560 the original ship was left. So philosophers have had a 0:07:42.640 --> 0:07:44.800 field day with this ever since then, because you know, 0:07:44.840 --> 0:07:48.200 it raises all kinds of questions about permanence and identity, 0:07:48.800 --> 0:07:51.040 and namely, you know, if if none of the original 0:07:51.080 --> 0:07:54.240 pieces are still in place, can you really still call 0:07:54.280 --> 0:07:57.200 it the ship of Theseus? Yeah, that's right, And it's 0:07:57.240 --> 0:07:59.440 kind of why so many people have this like brain 0:07:59.560 --> 0:08:02.160 over buddy bias when it comes to the self identity. 0:08:02.600 --> 0:08:04.520 I mean, the vast majority of the neurons in our 0:08:04.560 --> 0:08:07.360 brains form before birth, and stay with us our whole lives, 0:08:07.720 --> 0:08:11.160 unlike this constant turnover we experience in like red blood 0:08:11.160 --> 0:08:14.200 cells and almost every other part of the body. Maybe 0:08:14.240 --> 0:08:17.360 it's comforting, even on this like unconscious level, to tie 0:08:17.400 --> 0:08:19.000 your sense of self to something that's a bit more 0:08:19.040 --> 0:08:22.000 long lasting. That's an interesting thought. And this is kind 0:08:22.000 --> 0:08:24.480 of a tangent, but you mentioned red blood cells before, 0:08:24.520 --> 0:08:26.720 and it it reminded me of this weird study I 0:08:26.720 --> 0:08:28.800 found while we were doing our research. So, you know, 0:08:28.880 --> 0:08:32.080 you get dizzy or lightheaded when you move to higher altitudes, 0:08:32.240 --> 0:08:33.880 you know, like if you're hiking on a steep trail 0:08:34.040 --> 0:08:36.200 or heading up into the mountains or something. So this 0:08:36.280 --> 0:08:37.640 is hard for me to admit, but I never get 0:08:37.640 --> 0:08:40.760 tired when I'm climbing mountains. But I think, I think, 0:08:40.800 --> 0:08:43.560 I know what you mean. I'm sure that's true. Well, anyway, 0:08:43.600 --> 0:08:45.920 there's a special protein and our red blood cells that 0:08:45.960 --> 0:08:49.440 gets depleted when we're exposed to low oxygen levels. And 0:08:49.480 --> 0:08:52.480 when that protein is gone, other substances in our blood 0:08:52.520 --> 0:08:54.439 are then able to help us adapt to the change 0:08:54.440 --> 0:08:57.360 in oxygen. But here's the cool part. So our red 0:08:57.400 --> 0:09:00.800 blood cells don't replace that protein wants it's in which 0:09:00.800 --> 0:09:03.760 means that they're able to actually like remember their exposure 0:09:03.760 --> 0:09:05.959 to higher altitudes for the next time you had to 0:09:06.080 --> 0:09:09.280 higher ground. Wait, that's crazy. So when I head back 0:09:09.320 --> 0:09:12.560 to the mountainline body actually acclimate's faster than before. That's 0:09:12.559 --> 0:09:14.840 exactly what happens. I mean. The only catch is that 0:09:14.880 --> 0:09:17.520 four month lifespan you mentioned before. So if you wait 0:09:17.600 --> 0:09:20.320 longer than that before you return to the higher altitude, 0:09:20.600 --> 0:09:23.600 those red blood cells that remembered your last excursion, they'll 0:09:23.600 --> 0:09:25.560 be gone, and you know you'll have to teach a 0:09:25.600 --> 0:09:29.080 whole new crop of cells about that shortcut to being acclimatized. 0:09:29.280 --> 0:09:31.920 Well that's pretty amazing, But did you realize that human 0:09:31.960 --> 0:09:34.640 fat cells last ten years on average, So we could 0:09:34.640 --> 0:09:37.640 take a full twenty five years before they're all finally replaced. 0:09:38.160 --> 0:09:41.040 Really that long? So what happens if we like exercise 0:09:41.160 --> 0:09:43.240 like crazy? Wouldn't that help some of them go away 0:09:43.320 --> 0:09:47.920 more quickly? Afraid not, our fats all count is this constant, 0:09:48.000 --> 0:09:50.760 So when we gain or lose weight, that doesn't actually 0:09:50.760 --> 0:09:52.679 affect it at all. The ones we have just grow 0:09:52.760 --> 0:09:55.360 bigger or smaller, depending on which way we're tipping the scales. 0:09:55.600 --> 0:09:58.679 So you're saying, no, matter how overweight or underweight or 0:09:58.720 --> 0:10:01.559 whatever we are, we would still have the same number 0:10:01.559 --> 0:10:04.240 of fats. Yeah, exactly the same number. We're stuck with them. 0:10:04.240 --> 0:10:06.840 That is crazy. So, I mean, it's it's it's bizarre 0:10:06.880 --> 0:10:08.920 that they can last more than a quarter of our 0:10:08.960 --> 0:10:11.640 lifespan compared to these other cells. I know. It's even 0:10:11.640 --> 0:10:14.000 longer than the turnover on our bones, which are completely 0:10:14.040 --> 0:10:17.360 refreshed with new cells every ten years. And it's similar 0:10:17.440 --> 0:10:19.559 our muscles, which tend to make it fifteen years before 0:10:19.559 --> 0:10:22.280 being replaced. That's so weird to even think about, Like 0:10:22.320 --> 0:10:25.840 our bones being replaced from our muscles, that's bizarre. But 0:10:25.840 --> 0:10:27.920 but not every muscle. I mean, our hearts are actually 0:10:27.960 --> 0:10:30.720 one of the few things that last our entire lives, 0:10:30.840 --> 0:10:33.439 or at least most of it. See, our heart cells 0:10:33.480 --> 0:10:36.480 regenerate very slowly. I think it's about one per cent 0:10:36.640 --> 0:10:39.400 of a year old's heart cells are replaced each year, 0:10:39.880 --> 0:10:43.240 and that number actually continually decreases as you get older. 0:10:43.600 --> 0:10:45.760 In fact, less than half of your heart cells will 0:10:45.800 --> 0:10:49.080 actually be replaced over the course of your entire life. Well, 0:10:49.200 --> 0:10:50.920 I kind of like that there's at least one body 0:10:50.920 --> 0:10:54.160 part we can depend on for a little constancy. Right. Actually, 0:10:54.160 --> 0:10:56.240 I read the study a new scientist that gave me 0:10:56.320 --> 0:10:59.719 yet another reason to appreciate the human heart, because apparently 0:11:00.040 --> 0:11:02.600 listening to your own heartbeat can actually help you read 0:11:02.640 --> 0:11:05.360 someone else's mind. All right, I think you're gonna need 0:11:05.400 --> 0:11:07.000 to walk me through this when I'm trying to process 0:11:07.040 --> 0:11:10.360 what you just said. Sure, so, most creatures have this 0:11:10.440 --> 0:11:14.360 weird ability called inter reception that that it lets us 0:11:14.400 --> 0:11:17.120 sense the internal states of our bodies, like when we 0:11:17.160 --> 0:11:19.920 feel hungry or thirsty, you know, that kind of thing. 0:11:19.960 --> 0:11:22.800 And many researchers think this ability is actually what allows 0:11:22.880 --> 0:11:26.000 humans to generate emotions. For example, like imagine you're walking 0:11:26.040 --> 0:11:28.120 alone at night and you hear the footsteps of someone 0:11:28.160 --> 0:11:31.080 sticking up behind you. Like, the idea is that you're 0:11:31.280 --> 0:11:33.880 only going to feel afraid once you've noticed your own 0:11:33.920 --> 0:11:37.040 body's internal state, like the increase in your heart rate 0:11:37.120 --> 0:11:38.679 or the hair is standing up on the back of 0:11:38.720 --> 0:11:41.160 your neck. Yeah, but I mean that kind of just 0:11:41.200 --> 0:11:43.360 sounds like reading your own mind or something. So how 0:11:43.360 --> 0:11:46.040 do other people figure into this? So that's what I 0:11:46.080 --> 0:11:48.719 was thinking too. But there's this researcher at Oxford named 0:11:48.800 --> 0:11:50.640 Jeff Bird, and this is what he wanted to know, 0:11:50.720 --> 0:11:53.800 so he assembled a group of seventy two volunteers and 0:11:53.960 --> 0:11:57.679 measured their inter reception abilities by having them uh, they 0:11:57.679 --> 0:12:00.440 had to count their own heartbeats without actually taking their pulse, 0:12:01.000 --> 0:12:04.120 and then the participants watched videos of different social interactions 0:12:04.160 --> 0:12:06.400 and answered questions that were meant to test how well 0:12:06.440 --> 0:12:10.760 they could I guess infer the mental states of the characters. So, 0:12:10.840 --> 0:12:13.280 for for example, one scene showed this man making a 0:12:13.320 --> 0:12:16.640 pass at a woman who was clearly interested in someone else, 0:12:16.840 --> 0:12:21.000 and the question post was is she feeling annoyed? And 0:12:21.040 --> 0:12:23.120 as it turned out, the participants who were better at 0:12:23.160 --> 0:12:26.160 counting their own heartbeats actually performed better at this kind 0:12:26.200 --> 0:12:28.920 of question, like their ability to track their own internal 0:12:28.960 --> 0:12:32.080 states made them more empathetic to the feelings of others. Wow, 0:12:32.120 --> 0:12:34.000 that's pretty crazy, and I don't want to name any names, 0:12:34.000 --> 0:12:35.320 but I feel like we know a few people who 0:12:35.440 --> 0:12:39.160 must be horrible at counting their heartbeats. But but just 0:12:39.200 --> 0:12:41.160 their feelings, right, I mean, they couldn't tell what a 0:12:41.160 --> 0:12:43.079 person was planning to have for dinner or something just 0:12:43.120 --> 0:12:45.160 because they were, you aware of their heartbeat or so 0:12:45.240 --> 0:12:48.240 definitely not. I mean, when participants were asked questions about 0:12:48.240 --> 0:12:51.840 a character's thoughts that didn't involve emotion, the more terraceptive 0:12:51.880 --> 0:12:54.720 people lost their edge. But either way, I thought it 0:12:54.760 --> 0:12:57.480 was amazing that being in touch with your physiological state 0:12:57.640 --> 0:12:59.719 not only makes you more aware of your own emotions, 0:12:59.840 --> 0:13:02.120 but also of those of other people. That is a 0:13:02.200 --> 0:13:19.160 pretty awesome ability. You're listening to part time genius and 0:13:19.160 --> 0:13:22.200 we're talking about many of the eccentricities of the human body. 0:13:22.800 --> 0:13:25.120 All right, mago, So before we leave the cellular world 0:13:25.200 --> 0:13:27.560 behind for good, I do want to mention what is 0:13:27.600 --> 0:13:30.360 maybe the weirdest thing about the human body, and that's 0:13:30.360 --> 0:13:33.760 just how little of it is actually human at all. Wait, 0:13:33.760 --> 0:13:36.240 what are you talking about. Well, according to estimates from 0:13:36.320 --> 0:13:40.120 multiple scientific studies, there are ten times as many bacterial 0:13:40.160 --> 0:13:42.800 cells in our bodies as there are human cells. And 0:13:42.840 --> 0:13:44.680 we talked a little bit about this in our Clean 0:13:44.760 --> 0:13:47.240 episode way back when one of our first episodes where 0:13:47.240 --> 0:13:50.120 we talked about the microbiome. I mean, just think about 0:13:50.200 --> 0:13:53.400 for a second. Most of our bodies are not actually 0:13:53.520 --> 0:13:56.360 our bodies, and from the outer surface of our skin 0:13:56.480 --> 0:13:59.440 to the pits of our stomach, we're literally crawling with 0:13:59.480 --> 0:14:02.559 far in my grow organisms. Yeah, I mean an infestation 0:14:02.559 --> 0:14:05.280 of body bugs is deeply unsettling to me, and it 0:14:05.360 --> 0:14:07.120 might be another reason why we prefer to think of 0:14:07.160 --> 0:14:10.200 ourselves as brains and not bodies. But you know, on 0:14:10.240 --> 0:14:13.000 the bright side, the bacteria inside as do help with 0:14:13.040 --> 0:14:16.200 all kinds of important bodily functions, like I don't know, 0:14:16.320 --> 0:14:20.960 channeling the nutrients from our food and supporting our immune systems. Yeah, 0:14:21.000 --> 0:14:23.680 and and thankfully they're pretty easy to ignore to you know, 0:14:23.720 --> 0:14:26.600 since bacterial cells are so much smaller than human cells, 0:14:26.640 --> 0:14:29.240 we we really don't ever have to look at them, 0:14:29.240 --> 0:14:31.320 although honestly, I don't know if I can forget about 0:14:31.360 --> 0:14:33.800 them after reading that. If you somehow managed to gather 0:14:33.920 --> 0:14:36.600 up all the bacteria living inside you, it would be 0:14:36.720 --> 0:14:40.200 enough to fill up a half gallon jug. That's so disgusting, 0:14:40.200 --> 0:14:42.040 and I don't know why, but stuffing them into a 0:14:42.120 --> 0:14:47.000 jug makes them even gross. Although do you know, according 0:14:47.000 --> 0:14:50.120 to the Belly Button Biodiversity Project, out of robbed on 0:14:50.280 --> 0:14:52.800 lab our navels are actually one of the best places 0:14:52.840 --> 0:14:55.480 to store our microbes. In fact, there are more than 0:14:56.320 --> 0:14:59.640 bacterial strains living in there. That's pretty gross and kind 0:14:59.680 --> 0:15:02.560 of amazing. But actually I think I'm more blown away 0:15:02.600 --> 0:15:04.560 by the fact that there's a program devoted to the 0:15:04.600 --> 0:15:07.480 biodiversity of our belly buttons. You said it was called 0:15:07.480 --> 0:15:12.120 the Belly Button Biodiversity Project. I love that. Well. So 0:15:12.240 --> 0:15:14.080 did they figure out if it makes a difference whether 0:15:14.120 --> 0:15:16.480 you have an any or an audie? They did, so 0:15:16.600 --> 0:15:19.560 it turns out bacteria doesn't discriminate between belly buttons because 0:15:19.560 --> 0:15:22.600 the same amount turns up in both kinds. All right, So, 0:15:22.840 --> 0:15:25.080 now that we've done away with the pesky misconception that 0:15:25.120 --> 0:15:29.160 we're independent living beings instead of these walking, talking Petrie dishes, 0:15:29.520 --> 0:15:31.360 why don't we talk about some other things that our 0:15:31.360 --> 0:15:35.200 bodies do that we've been totally wrong about all along. Sure, 0:15:35.320 --> 0:15:37.520 and I've actually got a great one. So this is 0:15:37.520 --> 0:15:39.440 something I've been wrong about for a long time, and 0:15:39.480 --> 0:15:42.200 it's why are fingers and toes turn all pruny and 0:15:42.200 --> 0:15:45.600 wrinkled when we go swimming or take a bath. I've 0:15:45.600 --> 0:15:47.640 always heard that it had something to do with like 0:15:47.760 --> 0:15:50.760 water being absorbed into your like outer layer of skin 0:15:50.960 --> 0:15:53.440 and so the bulge in some places or whatever. But 0:15:54.120 --> 0:15:57.440 that's all wrong. Apparently, um I saw I saw this 0:15:57.480 --> 0:16:00.720 from researchers at two AI labs, and wais the Idaho, 0:16:01.120 --> 0:16:04.320 and they confirmed a different theory. They had these volunteers 0:16:04.320 --> 0:16:06.720 pick up a bunch of wet marbles of all different sizes, 0:16:06.960 --> 0:16:10.160 and some people use their regular dry hands to grasp 0:16:10.200 --> 0:16:13.840 the marbles, and others used wrinkly, pruny fingers that they 0:16:13.840 --> 0:16:16.120 had soaked in warm water for half an hour. Like, 0:16:16.200 --> 0:16:18.920 I just love that someone designed this experiment. But as 0:16:18.960 --> 0:16:21.920 it turned out, the participants with wrinkled fingers were way 0:16:22.000 --> 0:16:24.840 faster at picking up wet marbles than people with dry fingers. 0:16:25.360 --> 0:16:27.560 So all right, so our fingers and toes get pruney 0:16:27.600 --> 0:16:29.880 to help us grip wet things. Yeah, I mean, the 0:16:30.160 --> 0:16:32.680 process basically works the same way that rain treads do 0:16:32.760 --> 0:16:35.480 on car tires. But the really cool thing is that 0:16:35.560 --> 0:16:39.000 the wrinkling is this involuntary reaction that's controlled by the 0:16:39.000 --> 0:16:41.840 same part of the body's nervous system that that actually 0:16:41.840 --> 0:16:45.480 handles stuff like breathing or or us sweating. The blood 0:16:45.560 --> 0:16:49.160 vessels blow our skin constrict automatically, which tightens the skin 0:16:49.240 --> 0:16:52.680 above them to form the wrinkles. That's pretty interesting. But 0:16:52.680 --> 0:16:54.680 but why do our bodies play so much importance on 0:16:54.760 --> 0:16:57.800 getting a grip on wet objects? I mean, it seems 0:16:57.840 --> 0:17:00.520 strange that it's lumped in with these crucial access He's 0:17:00.560 --> 0:17:03.800 like breathing and sweating and things like that. So I 0:17:04.240 --> 0:17:06.440 was curious about that too, And the researchers in Boise 0:17:06.600 --> 0:17:10.080 suggests that the wrinkling might be this evolutionary holdover back 0:17:10.080 --> 0:17:12.840 from when our ancestors had to gather wet vegetation from 0:17:12.840 --> 0:17:15.439 shores like streams or river beds, and it was the 0:17:15.440 --> 0:17:17.240 same with their toes. I mean that was helpful because 0:17:17.240 --> 0:17:20.080 it was useful for getting around on slippery rocks. It 0:17:20.080 --> 0:17:23.040 actually reminds me of another body misconception, and that's the 0:17:23.080 --> 0:17:25.359 idea that fingerprints are there not only to help us 0:17:25.440 --> 0:17:28.919 keep tabs on criminals, but to improve our grip. So 0:17:28.960 --> 0:17:30.840 on the surface, it makes sense that the grooves of 0:17:30.840 --> 0:17:33.840 our fingerprints might improve the friction rate between our skin 0:17:34.000 --> 0:17:36.040 and whatever it is we're holding, you know, like a 0:17:36.080 --> 0:17:38.679 glass of water or something like that. But according to 0:17:38.720 --> 0:17:41.119 a two thousand nine study from a group of researchers 0:17:41.119 --> 0:17:45.080 in Manchester, fingerpads with prints actually provide a third less 0:17:45.119 --> 0:17:49.520 contact with the glass than completely smooth fingerpads. That's so 0:17:49.600 --> 0:17:52.280 crazy that they actually hinder our grip, So why do 0:17:52.359 --> 0:17:54.760 we have them? Then I mean, I'm guessing they're not 0:17:54.840 --> 0:17:57.920 just for detecting crimes or whatever. Right, well, they're there. 0:17:57.960 --> 0:18:00.399 Their true purpose is still a little bit of a mystery, 0:18:00.440 --> 0:18:03.439 but there are definitely some prevailing theories out there. One 0:18:03.480 --> 0:18:05.480 of them is that when we touch something the skin 0:18:05.600 --> 0:18:08.680 vibrations that occur between the ridges of our prints, will 0:18:08.720 --> 0:18:11.280 they help us to feel these fine textures that we'd 0:18:11.320 --> 0:18:15.840 otherwise miss. There's another suggestion that fingerprints wick water away 0:18:15.840 --> 0:18:18.520 from our fingertips, and that allows the skin to stretch 0:18:18.600 --> 0:18:21.199 more easily, so it can keep from becoming blistered or 0:18:21.320 --> 0:18:23.960 torn through use over such a long period of time. 0:18:24.320 --> 0:18:26.960 That's pretty cool. So while we're talking about misconceptions, this 0:18:27.080 --> 0:18:29.800 is other one I came across, and it's what should 0:18:29.800 --> 0:18:32.560 be considered our most valuable body part. And what do 0:18:32.600 --> 0:18:34.520 you mean by valuable? Like how much you can sell 0:18:34.520 --> 0:18:36.800 a kidney for on the black market or no, I mean, 0:18:37.000 --> 0:18:40.160 although you know you can get two for one of those. 0:18:42.240 --> 0:18:46.040 So this is about skin, and particular it's the foreskins 0:18:46.080 --> 0:18:49.720 from freshly circumcised newborns. So there was this time when 0:18:49.720 --> 0:18:51.719 these little pieces of excess skin were just thrown out 0:18:51.760 --> 0:18:54.639 in the trash, But now that scientists understand the growth 0:18:54.640 --> 0:18:57.399 potential of embryonic stem cells, like the ones in an 0:18:57.440 --> 0:19:00.280 infant's foreskin. They're actually being used to grow all kinds 0:19:00.280 --> 0:19:03.360 of skin for medical treatments. And in fact, a bit 0:19:03.400 --> 0:19:06.240 of foreskin the size of a postage stamp can actually 0:19:06.280 --> 0:19:10.040 produce about four acres of new skin tissue in a lab. Yeah, 0:19:10.080 --> 0:19:12.240 and and that can be used for like grafts for 0:19:12.320 --> 0:19:15.680 burns and other injuries. Alright, So so you meant valuable 0:19:15.720 --> 0:19:17.920 as in like beneficial, So that yeah, that that makes 0:19:17.920 --> 0:19:19.720 a lot more sense. I just wanted to clarify that 0:19:19.720 --> 0:19:22.160 that makes sense though. Well, I mean, the medical benefits 0:19:22.160 --> 0:19:24.480 are obvious, but you're crazy if you don't think there's 0:19:24.480 --> 0:19:27.320 money to be made there too. I mean, labs and 0:19:27.359 --> 0:19:30.560 cosmetic companies making millions in profit thanks to the skin 0:19:30.600 --> 0:19:33.920 they received from hospital donations. Yeah, but what are you saying? 0:19:33.920 --> 0:19:35.320 We talk a little bit about what happens to the 0:19:35.359 --> 0:19:37.760