Herman Pontzer
Appearances
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Yeah. So that's a funny piece about human sexual biology is that there is less sexual dimorphism than even in Lucy. So Lucy is still pretty significant sexual dimorphism. She's tiny. The males are not tiny. Right. And so there's probably a lot of male-male competition. That's what you'd have to infer. And you get to our genus, the genus Homo, and that all of a sudden starts to go away.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
And you get to the sort of 5%, 10% dimorphism that we see today. Is it only 5% to 10%? It depends on the metric. So in terms of height, probably about 10%. In terms of strength, for example, it can be 20, 30%. It would depend on the population too. But so here's what's also fun. In humans, males are just competing against males for mates. Females are competing against females for mates.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
That's another obvious piece that's very different. I'm sure that there's some kind of interesting female competition happening within chimps, for example. but it's subtle. It's mostly inherited. There's status. So females in chimpanzees, they leave. So they can't inherit status from mom because mom's not there. They grow up in a community. When they hit puberty, they go to the other community.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
So females are always new. Males stay. And the males are duking it out for where they are in the hierarchy. And there's friendships too. It's not all mean. So in bonobos, for example, it's a bit different. Female groups are dominant to males in bonobos. A male's rank has everything to do with mom and his best female friends. It's a matriarchy.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Kind of more so, yeah, in terms of where the power dynamic lies. Interesting.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
You could call that a move away from pure physical competition to more intellectual competition.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
The intellectual complexity that kind of runs away and becomes these huge brains that are three times the size of a chimpanzee brain. You end up having to learn so much to be a successful adult that childhood gets strung out. So there's this 15 year, 20 year gap between being born and being a capable human. No other species is like that.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
So there's this long period where adults are working harder than they have to feed themselves because they have to bring enough food home not just to share with everybody. But if you were just sharing with other adults that were all... It's kind of a one-to-one. Yeah. But because you're also trying to feed all the young ones, now you've got to get even more than you had to get before.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
So it changes the whole economics of all the calorie gathering, basically the food gathering. And we have these extended childhoods because of how much there is to learn because of how complex we get. And that's what people get wrong about brains too. People get really nervous about kind of the biology of intelligence. Again, the racists are happy to talk about the biology of intelligence.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Charles, what's his name? Charles Murray. Charles Murray. But what people, I think, get wrong about it is to understand how the human brain works, you're born unfinished. And you have to be born unfinished. Because there's so much to learn that your brain's job is to learn how to work in its culture today.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
It can't be hardwired because it's going to change so quickly that if you genetically encoded what you're supposed to learn, that wouldn't work. Because it won't work next generation. It won't be adaptive. That's right. So your brain comes in completely unfinished.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
And you spend 15 years literally constructing your brain because every time you make a new memory, you're plugging neurons together, you're taking other ones apart. Building this neural network. We measure something like IQ and we think, oh, that's something inherent about the brain.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
It can be, if it's a really controlled setting, you could begin to understand how well a brain builds or doesn't build those connections. But pretty much if you compare across people or across cultures, what you're measuring is the content that got built in there. It's a content measure. It's not an ability measure.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
The brain is the most expensive organ in the body. And when you are five years old, it's at its peak need. Something like half of your resting energy expenditure, the calories you're burning minute by minute as you just rest there as a kid, are going to your brain.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Yes. And inside what's going on is even more active than it would be as an adult.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Yeah. This is not going to be very satisfying. I think that's a false dichotomy because we're doing both things. We're in this really complex social world and you got to be good at that. You suck at that. I'm sorry. Your reproductive success is not very high.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Because they're good at the other part of it, which is the foraging piece. Today's foraging is getting a job that you can bring home resources, right? Right. So you got to be able to do both. If you look across all primates, the biggest brain species are the ones that have the hardest job to do figuring out how to go get food. It's not the ones with the biggest social groups.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
But that doesn't mean that in any one case, it's not a combination of things. You get these big trends and then the one-off cases, like humans are the extreme one-off case. There's nothing else like us.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
And speaking of tech bros, I'll say that in my line of work, you get emails regularly, Dear Dr. Poncer, I have figured it out. Yeah. Here's how it all works together. And here's the silver bullet thing that nobody's thought of. And it's just the one thing. And the proportion of those emails from engineers and retired doctors is disproportionate to their numbers on their grades.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
So there's something about that training of seeing things in a black and white way. Yes. And I give them credit for spending time thinking about this stuff. It's fun to think about and doing a good job. I don't want to be too harsh on it, but the sort of black and white feeling of how things work and knowing that, well, then it must just be this one thing. And it's never one thing, is it?
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
The hockey stick inflection point is when you start hunting and gathering. And then from there on out, it's been just a climb. The way that we're figuring this out is we're going to the field, we're digging up fossils, we're measuring the skull sizes. I've had a chance to do some of that. That's really fun work.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
It's like putting the frames of a movie back together, only it's a 2 million year long movie. Even if you had 100 frames, that's not enough.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
There's a fun story there that the first project I did with them was measuring energy expenditures, metabolic rates, how many calories you burn every day. For your book, Burn. It ended up in Burn. That's exactly right.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
But nobody measured it. Lots of estimations about what that would look like. It kind of feeds into questions in public health because maybe obesity is a big problem in the U.S. because, well, we're not burning as many calories as we should be. Maybe we should be burning like hunter-gatherer level calories. Yeah. But we're not. And then that also gives rise to a whole paleo movement diet.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Matching? So, like, when you hug each other, it forms a fool? Yes, yes.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Yes, all of it. So looking into it, I was like, wait, this is all based on? Nothing. It's just estimates, you know. We don't really know any of this stuff. Let's go see. And so a couple of collaborators and I went. One of the guys I work with is Brian Wood. He's at UCLA now, your alma mater. Okay, great. He must be a genius. Yes, of course, of course.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
He's spent more nights in a Hadza camp in the past 10 years or 20 years than he's probably spent at home. He's there a lot. We go and we do this project and we're measuring energy expenditures. We're measuring how many calories you burn every day over about a week, week and a half. And we use this isotope tracking technique. It's the best, coolest way to do it. Gold standard.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
So that we know the numbers are real. Could you explain that for a second?
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
I'll go as deep as we want. Yeah, I love it.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Let's go. Good, exactly. It's called doubly labeled water. You drink a half glass full of water. So water's H2O. Some of the H's are different. Some of the O's are different. There are different versions of those elements. And you can track that if you took a water sample and put it in a mass spectrometer. That's a machine that would measure how much of those different elements are there.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
You could use it like tracers, basically. You drink some of that water, and over time, you're going to flush all the marked hydrogens out because you're peeing and you're breathing out water vapor. All the water you lose, the hydrogen is the marker of that. The oxygen you'll also lose is H2O. But it turns out you also lose oxygen that you drink.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
It gets mixed up with all the oxygen and carbon dioxide that you're making in your body. And you end up breathing out those oxygens as CO2 as well. So those oxygen elements, oxygen isotopes get lost two ways. The hydrogen isotope only gets lost one way. If you look at the difference in rate of loss, you can figure out how much carbon dioxide the body's making. That's calories per day.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Okay. Did you ever see Groundhog Day? Yes. Poxawani, what is it? Punxsutawney. Punxsutawney. So, we played Punxsutawney in high school ball. They were that close. Oh, okay. Yeah, yes. They kind of nailed it. That's sort of the vibe. I lived in Brooklyn for a few years, and it almost broke me. It was the F-trained. You'd be like on the F train at nine o'clock in the morning.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
You cannot burn calories without making CO2. You cannot make CO2 without burning calories.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Yes. We're not estimating at all. This is a real measure. And it got figured out in the 50s, but then we could use it for people in the 80s. And so people have been doing it since then. And it is the gold standard. Have you done it to yourself? Because I would want to do it. You have?
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
And what did you burn a day? 2,800 a day. Are you active physically? I am. I was sick that week, so I was less so. I'm not like bedridden, but I wasn't running as much as I like to.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Typical American male burns 3,000 calories a day. Typical American woman is going to burn 2,400 calories a day. Okay. Because you're lazy. If I had to guess, that's what you're burning.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
What's the real answer?
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
That's right. Anyways, back to the Hadza. So we go there, we do this study. We live in Hadza land for a summer. Basically, it's a big camping trip with scientific equipment, doing these measurements, hanging out, going on hunts, going on gathering outings. It's really amazing. Is it fun? It's so fun. And the people are just generous, wonderful folks. Bow and arrow. And what are they getting?
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Gazelles and stuff? Picture National Geographic Savannah. That's it. Zebra. Giraffe. Did you eat some zebra? I've had different animal foods, whatever they would bring home. I've had zebra.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
A and B, it's just the meat. Yeah, there's no seasoning. There's no salt. Very little salt and very little anything else. No dry rub. No. If they kill a zebra... You can't eat a zebra in one day. It's a huge thing. Even a camp can't eat a zebra in a day. And so they eat what they can right then. And then they bring all the meat home and they cut it into strips and they hang it from the trees.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
A camp is about 12 or 20, sometimes even smaller, but let's say a dozen grass houses in a nice part of the Savannah. And the whole camp just kind of smells like a butcher's shop for a week. It's kind of crazy.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
It isn't rampant. Any of these subsistence groups, if you look at hunter-gatherers, you look at farmers, parasites are like a part of life. And so I'm sure they have them more than, I hope, us three have them. I don't know. But no, it doesn't affect their day-to-day.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Oh, right. So we haven't gotten the result yet. We take the samples home. They get analyzed at a lab at Baylor. The internationally leading guy in this technique sends me the data back. And I'm just so excited about it because we're going to find out. They're burning double the calories. It's going to be so cool to see. And nope, it's the same.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
So they, as getting more activity in a day than a typical American gets in a week, are burning the same number of calories every day as the American. Total shocker, right? As a scientist, that's the best. Yeah. And so I went back to the guy, Bill Wong, he's the one who did it. I said, Bill, did we screw it up? Yeah, this can't be right.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
It was like a meat wagon. You just like packed in. Just to pass the time once, I was like, I wonder how many people are on this train. I did the math and then how many cars there are. And I was like, oh, there's more people on this train than there are in the hometown I grew up in.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
And he said, no, no, no, the data, because there's internal checks they can do it. Data look great. And I said, then what's going on? And he goes, well, we see this sometimes. They're more efficient. And I go, oh, thank God. Somebody understands what's going on here. And I said, what do you mean? And he goes, well, they burn fewer calories than you thought they would.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
I go, that's not an explanation. And so that's been the last 15 years of my career. A big part of it has been trying to understand this phenomenon because it's not just them. We've done this in other cultures. We've done this in other species. And activity doesn't sort of link up with your daily expenditure the simple way that people think it does.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Vice versa the other way.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
I think what it does is it helps explain why people have such trouble doing the calories in, calories out thing. First of all, it's hard to know how many calories you're eating. And then secondly, it's very hard to know how many calories you're burning because it isn't just how active you are.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
It turns out. Yeah. Okay. Now it's like, well, yeah, it's calories in, calories out, but good luck tracking either of those things. It sort of sends you back to square one of like, how do I find a way to do this? If I'm really worried about diet and diet's the best way to handle your weight, which is true, then okay, then how do I find a way to do that?
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
It's figuring out a way to conserve energy on other things. When we were there, we brought it the sort of briefcase based respirometry system where you put a mask on a person that's cooked up to a little computer you wear on a chest harness. We can measure how many calories they burn to walk. That's the same. So the activity costs aren't lower. So they are really active.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
They're burning tons of calories on the activity. There's no secrets there. The fact that the total number of calories a day is no different than everybody else means there has to be something else going on in all the other things that your body's doing, saving energy here or there, squirreling it away. And that's interesting.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Yeah, what was the population? So 800 people in my hometown of Kersey, Pennsylvania. And what did mom and dad do? High school teachers. Okay, in Kersey? Kersey's not big enough to have a high school. So the town next door, St. Mary's, they were there. We were out to high school too.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
So an analogy to that would be really physically active people here in the States versus inactive people. Right. When we look at them, what we notice is people who are really physically active, they have less inflammation. Well, what's that? Your immune system isn't as active. Oh, okay. So we're saving some calories there, maybe. Your reproductive hormones aren't as sky high.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
They're actually really high in the sedentary Americans versus like the Hadza, for example.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
But on the way there, there's a very healthy point where your estrogen levels might not be as high as somebody who's sedentary. And maybe that's a good thing.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Yes. Stress reactivity. If you are an athlete or even if you just exercise regularly, if I scare you, your heart rate's going to go up, but less. You're going to have a smaller stress response. And if you measure how much cortisol you make all day or how much epinephrine your body makes all day, it's less if you are physically active. Yeah.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
It's kind of a disappointing amount. They do these tests where they have people play like chess against a game that's tuned just to be just a little bit better than them. So they're working their asses off and they're struggling. They lose anyway. It must be very frustrating. And it's like four calories an hour. It's nothing. It's like a couple M&Ms.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Probably not. Probably the brain is one of the pieces that's not getting touched. You can't really measure. And that's because most of what your brain is doing is completely off of your radar. It's all the organizational stuff, housekeeping stuff.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Yeah, it's working to keep you within an arrow range. Sometimes this gets misinterpreted like, oh, there's no effective exercise at all. No, there can be sometimes. You can see it.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
It's kind of a long story, but so the Ponser family was one of the first families to move into that area. It was not super densely settled ever. Even the Native American folks were like, this is a junky land. We don't want to spend a whole lot of time here. And so my extended family owns hundreds of acres of forest. Oh, wow.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Yeah. If you start an exercise program tomorrow, it's going to take a while for your body to adjust. So for the first couple of weeks, you haven't seen the adjustment yet. So you really are burning the extra calories that you expect to burn.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Yeah, so when we say no more calories than somebody else, those are all sort of size-adjusted comparisons. Right, because it doesn't make any sense for me to say that you and Monica burn the same number of calories. Obviously, it's going to be different because of the size difference. Right. And so when we do these population comparisons, we don't want to just compare sizes across populations.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
We want to compare adjusted for size. And so that's right. If you build more muscle, for example, then yeah, you'll burn more calories just because you are bigger.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
They'll go up. So that's a fun one. The other challenge to this idea is like, well, what about the Tour de France? You're burning 8,000 calories a day. 8,000 calories a day. It's some amount.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
So we know that there are periods the body can, at least for some short-term time, really crank it up. Thank you. Thank you.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Thank you. Thank you.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Yeah, yeah, yeah. I lived at the end of a dirt road in a house that my dad built physically with his hands. It was Buddy Dean. It was wonderful. I grew up riding motorcycles and hiking around and hunting. It was kind of an amazing way to grow up.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Thank you. Thank you.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
I mean, the first time I got an actual firearm, I think it was for my 10th birthday. A .22? Yep. But my life is so different now because in the academics university world, that's not a background that you see very often. Exactly. Right. It's kind of looked down upon. Oh, completely.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Thank you. Thank you. Thank you. Thank you. Thank you. Thank you.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Well, this is a whole other avenue, but we talk about diversity in the university and everybody is for that, but it means different things to different people. Yes. Yeah. It would be interesting to me to see diversity of backgrounds that way. You don't see a lot of folks from rural America in the ivory tower. No.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Thank you. Thank you. Thank you.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
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Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
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Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
And I think it's another case where if all humans were just born to be just one kind of athlete, just an endurance or just a power kind of thing, it wouldn't work because cultures change, the jobs you have to do change too quickly. So evolution has to solve that problem by creating flexibility and creating adaptability.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
So over the course of a lifetime, if you grow up someplace you're doing a lot of running, you'll get good at that. You grow up somewhere where you're working with your upper body, farming or canoeing, you'll get good at that. Like you see examples of all these things.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
I think about the folks I grew up with. One of my best friends growing up, he's a union electrician, still lives back in Kersey, and he's got a great life. That was an avenue that is a wonderful way to go, but he would never have considered doing what I'm doing. It wasn't even on the radar. Who knows what this kid's going to do? But it is really kind of dichotomized that way.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Humans are incredibly inherently diverse the way that we're built. Just look around. Any population, you're going to find the big people and the small people and the strong people and the thin people. You find all of it everywhere. And I think that is true. Humans are kind of inherently more variable. I think that also gets back to this issue of every lion has to be the best lion it can be.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
And there's a narrow, prescriptive way of how that's going to work for them to be a successful adult. In a human society, even a hunting and gathering society where the career options are more limited than maybe here, you're still going to see a variety of ways that are successful to be an adult. And so I think there's sort of more breadth of possibility there than in other species.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
I think that's probably true.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
The molecule that makes skin dark is a molecule called melanin. You've got these really cool cells that start off in this very special part of the embryo that migrate into your skin, and those cells make melanin. That's their job. And the more they make, the darker you are. And so we all make it less. We're melanin challenged.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
On a sunny day, I feel it. But even the baseline is variable, right? That's right. So if we were an African species, we know that 300,000 years ago, that's where we all were. Melanin is this natural sunblock. You see more melanin, darker skin in populations that have more ultraviolet light exposure.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
And it's because ultraviolet light is good because it helps you make vitamin D, but it's bad because it blows up this molecule called folate, which you need to make DNA. You are making two miles of DNA every second or something like that. that. It's crazy. And so if you don't make that right, that's a problem. There's no mitosis or there's cancers.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Or if you are pregnant and you are building a fetus, there's a lot of DNA being made there. And if that doesn't work out, that's not good, obviously.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Yes. You want to make vitamin D. You want to protect your DNA. And that balance is why if you're at a high sunlight area, you're going to be inherently adapted to be darker. Populations farther away are going to be adapted to be lighter and get more of that UV because that's the other part of the seesaw.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Yeah, so there's like 100 and some genes that work together to kind of figure out how much melanin you're going to make. You can imagine there's variants of those. We all have those 150 genes, but your versions might be different than mine. And so the versions that help make more melanin, those are going to be successful in high UV places like Africa.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
As you move north, the variants that make you a little bit lighter... All of a sudden, that's an advantage. And we see those variants get selected for to be lighter, and then people move back into more tropical areas with higher sunlight intensity, and we see the darker skin variants come back.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
In my mind, that says that you, Dax, could... Be black. Be black.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
No. But in our population, pick any population, you will find all the variants available. That's one of the big discoveries of modern genetics, is that those variants, the same variants that make some people darker, some people lighter, they're all there in the population. Even if no one's black? Potentially so, because what'll happen is they'll just be a much lower frequency.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
So maybe only 5% of people have one gene have the variant that would make you darker skin. Since it's a low frequency, it's unlikely they're going to have that variant and the other variant that helps and the other variant that helps and the other variant that helps that all together give you darker skin. But now let's make selection favor darker skin.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Well, now, bit by bit, you kind of reassemble the frequencies to make those alleles more frequent.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Yeah, so Lamarck would say anybody in their own lifetime can achieve that change. Right, right. That's not right. But what is right is that any population over enough time could end up going back and forth on these changes.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
No, I know. I was going to tell you that I'm actually here from UCLA. You know the anxiety dream where you have the class that you never finished and they tell you you have an exam? I have it with me here. We're here to do this with you.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
So he also had no idea about genes, and he thought that traits mix like paints mix.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
And if you do that, then you just get blah.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Yeah, he didn't have any idea about that. So he was out to lunch on how any of genetics works.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Whatever genes you've inherited from mom and dad, they're not all turned on all the time.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Yes, and this has been a big breakthrough in the last 15, 20 years of just how this works. The moment you're born, and maybe even before you're born, which is crazy. Mom's uterus. Passed on. You are listening. You're paying attention. And yes, you have all these genes from mom and dad, but you're not going to use them all. You're going to pick which ones you use.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
And then that creates diversity too.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
I doubt it, and here's why. That extra little patch isn't doing you a whole lot of good, first of all. But if you're upright all day. Yeah, but you're also not wearing as many clothes all day, probably, and you're outside the entire day. You probably get plenty of exposure anyhow. Here's who really needs the vitamin D, is mom. So why is her hair not falling out? Okay.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
So this is where I would push back and say, let's be sure that we're looking at an adaptation and not just a tolerated bit of noise. Ah. Right? Skull shape's a great example of this. Back in the bad old eugenics days, people were measuring the skull shapes of Eastern Europeans and Asians. Facial proximity. All these things, right?
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
And they're trying to figure out who's a good person and who's a bad person. Yeah.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Exactly. And you do that analysis today and you say, well, what if rather than assuming that I'm looking at selection favoring that skull shape here and this skull shape there, what if my model is, well, evolution doesn't care. It doesn't affect how you survive. It doesn't affect how many babies you have. Right. There's no real force acting on this. Yeah.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
So what if the model is, well, it's just noise. And we know what noise should look like. Noise should look like gray screen noise, right? There's just no real pattern to it. There's a very clear mathematical test you can make for that. And sure enough, if you look at skull shapes across the globe, it's noise. They don't mean anything.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
That's exactly right. And the reason why do we do it is because we seem to be inherently built to like to have in-groups, out-groups. And we're visual primates, man. Yes. So we pick something visual. It's easy. I think it's kind of inherent in the way that our brains are built to go that way. So it's not a surprise, but that doesn't make it right. It's a pretty crap way to do it.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Yeah, but what's crazy to me is that's still how we do it, not just casually. It's how you doctors do it. Doctors are still doing this race-based view. That's how they're trained. You come into the doctor's office, you get a medical test. And how I interpret that test is through a lens of if you're black, if you're white, if you're Asian.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
There's a thing called an EGFR, estimated glomular filtration. It's how your kidneys are doing. It's a blood test. I get a blood test. I run it through this analysis. I get a number. And that's your EGFR. Okay, is it good or is it bad? Well, it depends. If I'm a doctor and I'm interpreting that number, I ask, is the patient black or is the patient white?
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
That's fucking crazy because their kidney function has nothing to do with that.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Were you excited about the physical anthro, the cultural anthro? Were you like floor field? How did you do it?
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Again, at least it's a plausible mechanism there. To push back specifically on that one, if that were true, if that bottleneck with the slave trade were what was happening, we would see that in the genes that we know are related to hypertension risk. We don't see that. You don't? No. There is no evidence.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
And also, you can take black families who are not descendants of the slave trade, but they grew up in America where there is racism. They have the effects of that. So race becomes biological.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
So yeah, usually there's not even a story as to why. At least that one has a story.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Let's do more of the heart rate thing. So through the 80s and 90s, it was thought that black folks in America were just genetically predisposed to heart disease. This is how it is.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Accept it. Move on. And now we know, okay, well, actually, if you study folks that are black, and even if they're descendants of the slave trade, but they aren't in the United States exposed to structural racism, they actually don't have hypertension. That isn't a thing that all the folks have downstream. Wow.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
It's a stress thing. Yeah. Wow. Another great example. Native Americans in this country have, for all sorts of reasons, they also have hypertension and other sorts of bad heart outcomes. Over-index and diabetes. Is that because they're predisposed to it? Well, actually, if you also look at Native American groups in Bolivia, it's the same diaspora that came down. Uh-huh. The same folks.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
But they aren't living in a world that has... Oppressed them. That oppressed them. And so guess what? Healthiest hearts in the world in Bolivia, no signs of diabetes. So it's true that in this environment that gets triggered, that set of sequences. But what we're looking at is an environmental influence. We're not looking at some inherent biological predisposition.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
And what gets dangerous is if you say, well, that's just how those folks are. What can we do? Throw up your hands. That's a very different response. And you say, holy shit, this group does have an issue. We got to fix it. Maybe we can fix it. That's right.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
So the way that you understand how the body works ends up with big consequences for how you think about society, how we deal with all these problems.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Here's a fun one. My mother-in-law just had a DEXA scan done. She had her bone density checked. And they give you a bone density score, how mineralized your bones are. And then I was reading the report with her because she wanted some input. And they had this thing at the end. Your FRAX likelihood, F-R-A-X is the sort of algorithm they run the data through. Likelihood of major fracture.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
in the next 10 years is X. And I thought, oh, that's interesting. So I looked that up online. I'd heard about this. I wanted to look into it. You can go to the FRAX website. Any doctor would use this. Her doctor used this. You put in the bone mineral density. You put in your BMI. Are you frail? Are you robust? A-robustus? Yeah. Good. Age, sex, the things that are relevant.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
And then it also asks you, what's your race? Are you black? Are you Asian? Are you Caucasian? And I played with it. She grew up in China. She's Asian. If you put an Asian versus Caucasian versus African-American, you could change your risk by double or half.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Yes. And it's totally bullshit. I mean, there's no way that's right. And the training set that they must have used this on was capturing something about the environment of folks. And that's affecting your likelihood.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
It would be interesting. Yeah. I don't think we have a great answer. We know why menopause happens mechanistically, but we don't really know what triggers the exact timing, like why it's 47 versus 49. Yeah. I don't think we have a great handle on exactly what. Well, you run out of eggs and the body starts ratcheting up.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
So why do you run out of eggs earlier? Yeah. And why this time versus that time. Five years difference is a big difference. Why? Yeah. Who's early and who's later? I don't know. So the idea that your doctor is looking at the census box that you ticked and making real decisions. It's like, take your car to the mechanic. They say, well, we checked the timing bell.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
We checked the brakes and we think your car is going to be okay because it's blue. Like, well, what? Well, hold on. We did this as a diagnostic test. I mean, here's the numbers. But then it looks pretty bad. But the good news is you've got a blue car. Well, what the hell are you talking about? We do this. Well, we shouldn't.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
But that has to do with how that actually is built. Yeah. It's the relative system. The quality of manufacturing. This is literally as dumb as saying two Toyotas, both have rod knock, one's white.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
I went to Penn State not having any real idea what I wanted to do. I took a seminar in human evolution that was co-taught by a cultural guy and a sociobiologist, bioanthro guy. Yeah. And the cultural guy, the postmodern stuff had kind of passed him by, and he was not into that. And so he was a good foil for the evolutionary guy because they both kind of saw things sort of the same way.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Well, first of all, some species are getting pretty close. So you've got bristlecone pine trees that live 5,000 years. And aren't there some sharks that are like... Go to 600 years, I think. Oh my God.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
It may be apocryphal about the guy who discovered the oldest living organism. You guys ever hear this story? No. That was lovely. Maybe apocryphal, but it's such a good story. So it's a grad student in forestry and he's trying to study bristlecone pine trees for some reason. I think he's using the tree ring data to figure out environmental changes over deep time. This is in the 60s.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
It has a special tubular drill bit that you can drill it into the tree, pull it out, and you get this core sample of the tree. Look at the rings. He's starting his research, and he gets up there into the forests, probably somewhere out here in western U.S., and he starts drilling into a bristlecone pine, gets the thing stuck. And he's like, ah, I can't finish my dissertation. I'm in real trouble.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
So he goes to the ranger station and says, this is what happened. I'm so sorry. Can I cut that one tree down, please, to get my core thing out? And the guy's like, yeah, fine. So he cuts it down. Oh, my God. And is a good scientist about it and saves a section of it and counts the rings later on and goes, oh, my God, I just killed the oldest thing on the planet. That's risky.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
It was a 5,000-year-old tree.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Right. On one of the rings. Oh, it's incredible. When people argue for like a 6,000-year-old history of the Earth, the really serious anti-evolutionists, I think, man, we've got tree ring data older than that. We're sure it's older than that.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
We're the oldest living primate for sure, and we do a better job not senescing. So there's been selection there to push that process off. The standard story is that whatever the kind of damage that accumulates over time as we get older, your body has ways to fix that and repair it and put it back right. But that takes energy. Everything's a trade-off.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
So if my body's spending energy keeping myself alive, well, then I'm not spending those calories on reproduction. And that's the balance of that. And really, the reproduction part is what evolution really cares about. How many copies of your genes do you get in the next generation? So if you spent all of your energy on maintenance, then maybe you could live a lot longer.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
But that's not a great strategy because... Those genes won't make it to anybody. Exactly. So that's the standard story about why senescence happens. The mechanism of exactly what's happening at the cellular level, what's breaking down, why, that still is, I think, up in the air. The stuff I find convincing, too, is that it's kind of entropy.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
The wild number of chemical interactions that actually become, at that scale, physical interactions of molecules bouncing against molecules. Things get wrecked and broken, and you have to put them back together. The idea would be that that's why calorie restriction, for example— I don't know if you want to do it, but that's been the one thing shown in every species ever looked at.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
But even in like lab settings in mice, if you cut their calories by 20%, they live a lot longer.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
It kind of cleans up the scrap and uses it. Yeah. And it just creates less exhaust, less byproduct and less entropy.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
You got to play two games to try to live forever. One, we know the rules too, and we can do something about it, which is make sure you're exercising, eating a healthy diet. We can talk a long time about what that would look like. Don't smoke. Don't do things that we know lead to early drinking. I hate to say it, but I think drinking's not. All these things that we know how to do.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Cultural anthro and bioanthro can be very at odds.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
And that can push you through the kind of typical falling off the cliff that happens to a lot of us as we get older. But once you push into the kind of the 80s, 90s, then you got to hope you got good genes. Who's the guy who's trying to live forever? Is Brian Johnson? Yes, yes, yes, yes. And I don't know him and I wish him the best. Did you watch the doc?
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
The last thing I saw with him was him on Bill Maher's pod talking with him. Oh, okay. Yeah. I haven't watched the doc. I kind of keep up with him a little bit on social media because I think it's interesting. Yeah. I am aware of the routine, at least some of it. He'll have a really good chance of winning the first game. He's not going to die of heart disease. That seems unlikely.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Yes, he's going to do great. He's going to get to be 80 or 90, if I were to make a prediction. And then we're going to find out how mom and dad did in the genes category.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Yeah, so I don't know. The idea that you could have a life that's twice as long is, in my mind, the same as saying that I'm going to have a human that's twice as tall. There are thousands of genes that all work together to make a human-sized human. If you want to make a double-sized human, imagine all the things you'd have to change. It wouldn't just be make sure you feed them better.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
You've got to change genetically how you build the thing. And so lifespan is just another trait. Just like that. So what I think we're seeing now is there's enough good nutrition around the world, enough good medicine around the world. Please get vaccinated. Take your antibiotics. Take the medicine you need to take. We can get you to 80, 90 relatively. That happens for a lot of folks.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
That's wonderful. And even over 100. But then you start hitting the genetic limits of what's possible. Yeah. Right. That's how I read it. And I'll be happy to be wrong. Do two minutes on vaccines. Well, as the measles outbreak right now in Texas, it lets us know they're an important public health thing to do. The vaccination schedule is critically important to keep.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
There's a reason all those are in there. Those are all diseases that really harm kids and have lifetime effects and sometimes death. But I mean, these are really nasty things. Vaccination is one of the greatest medical discoveries ever. It goes back to the 1700s. George Washington was vaccinating his troops against smallpox.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
So there's a lot of that kind of schism still now, but luckily for me, these guys complimented each other well, and that class just lit my hair on fire. I mean, it was amazing. My parents were both high school teachers. It was a home where we talked a lot about ideas and had arguments that were good arguments. It was really fun growing up, and it was such good training looking back.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
That's exactly right. That and clean water, and you basically have the modern world.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
And without those things, you don't.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
And the way they work is this really clever thing that your immune system has cells that are listening, looking for infection, and they learn how to identify it and kill it and make antibodies to it. And you are evolved to have this adaptive response that vaccines kind of take advantage of. The idea that it's sort of unnatural is bullshit.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
It's completely using this natural system that your body has evolved. And then the other thing that people always want to tie it to are developmental issues and autism, of course. And all of that's been completely debunked. Just all such bullshit. And yet it just won't die. People really want to push it. And it's kind of scary.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
From my perspective, I think, man, if we can't hold on to that advantage, right, then what are we doing?
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
It's a great example of this thing that's become associated with the political right since COVID, but actually before that was very much on the political left. Yes.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
The is-ought fallacy, we ought to teach that better, right? Just because something is some way doesn't mean it ought to be that way, first of all. So just because polio exists in the natural world doesn't mean that we ought to just say, yes, let's have it.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
They were English teachers, so evolutionary biology wasn't their thing, really, to sort of have a whole other way to look at the human species in this evolutionary deep time perspective. And all these quirks and weird things about you think, oh, but actually there's a reason for those.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
It's because they were protected against COVID. They were happy. Yeah.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Yeah, I know. But there has to be a place where we say we appreciate your beliefs and everybody has their own perspective, but that we are going to pay attention to the numbers. There has to be some agreement about an evidence-based way of making decisions.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
100%. And they're not old enough. The age of consent is there for a reason, right? And they're below that. They're powerless to voice a different view.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
So that's really worrisome. I mean, it's, well, yeah, if we want to get into this, but we're watching right now in real time, maybe the dismantling of one of the most amazing industries medical research apparatuses that there ever has been. And it's starting with the way that HHS is potentially being led by somebody who's really skeptical about vaccines. That's scary.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Yeah. All the way down through, they're changing the way that NIH is going to run, International Science Foundation is going to run. I don't think people appreciate just how radical this is. I mean, this is the world I live in, university research. People are really afraid about what the next year is going to look like. Yeah. Yeah. Are we gonna be able to do medical research?
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Is there gonna be the next discovery for the next vaccine? Is there gonna be the next discovery for the next medicine or the next treatment? Because maybe it's gonna be very different, maybe not. But it's much harder to fix things than it is to break them. And so the timeline, when we say in two years, gosh, where's the pipeline for new drugs?
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
It's not gonna be six months to put it back together like it was six months to take it down.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Thanks. It's trusted.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Thanks for having me. Really fun.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Right. And you begin talking about the ways that populations differ or even just more fundamentally how people differ. And because of that really dark history, people get nervous right away. The sort of superpower that an anthropology background gives you is you spend four years in college talking about this, trying to dissect. People are different. That's a good thing. How and why?
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Yes, and how much of it's noise and how much of it's signal, because there's a lot of noise, and how much is different within groups versus between, it gets less scary. You go, okay, that's how that works.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Yeah, and I think right now, when I look at social media world, which has gotten even weirder recently, the only people who want to talk about difference that way are... The race realist. That's a new word for eugenics. What do they call it? Race realism. Race realists. This kind of thing.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
It's really kind of scary. And so you don't have anybody with any real background in how this works talking about it because everybody's afraid to.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
So let's talk about it in a way that's evidence-based, that's less scary. Let's unpack it. I think you have to start with how the body works, right? Because I think people don't have a fluency in that. How does embryology work? How does the brain work? How do your muscles work? I mean, if you start with those pieces, then you can say, well, then how come...
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Your physique is different than yours or mine. How does skin color work? Now we can understand why skin colors differ. And it's not a scary thing. This is the biology of it. That's how we talk about it.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Oh, yeah. Well, we're part of the great ape family tree. Our lineage kind of busts out about 7 million years ago, breaks away from the lineage that becomes chimps and bonobos. But the first 5 million years, I think of it as basically the Ewok chapter of human evolution. You're walking on two legs, but you're furry and kind of ape-like. Are you fully bipedal? Well, people argue. Let's just say yes.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Okay. Earliest ones probably have a grasping foot. We see that in a couple of these, like Ardipithecus genus. That's changed since you left. Yeah, I know, A.F. Orensis. Prior to Lucy's A.F. Orensis, it was Ardipithecus. The initial stuff was found in the 90s, but wasn't fully reported until 2009, I think. Oh, so I was nine years out. Yeah, I don't know. Wait, so he's what?
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
He's walking on two legs.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
So as far as we can tell, the earliest, earliest ones, even before that one, are walking on two legs. The evidence for that is, if you look at the skull of one of the earliest fossils we have, you can figure out the orientation of the spinal column. And if it comes straight down out of the head, vertical, then it's probably on two legs.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
And if it comes towards out of the back, then it's probably on... So that's kind of the kind of ways they put these things together. Isn't it, Nate? I love that stuff.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Yeah, but that's like our long lost Asian cousin. Right, that was in Asia. That was a giant biped. Still is the biggest ape ever. Wow, how big? Twice the size of a gorilla or something crazy like that. They're really, really big. Think Bigfoot.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
There's a wonderful story of a professor, I think he's in Idaho, who did his whole PhD on very normal anatomy and questions in anthropology. And then once he had tenure, he was like, yes. Let's party. And that was like all about Bigfoot.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
No, but they're 450 pounds. Right. I don't know, six feet tall. Let's go six feet tall. Okay. I had to guess. I'm not sure how much full skeletons of it either we have. We have mostly cranial dental stuff, heads and teeth.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
I've got to write a new book.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
That's right. And so you've got these bipeds. They're walking on two legs, but they've got grasping feet, at least for the first couple million years. Then you get Lucy and Australopithecus afarensis, and that's another very successful chapter.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Okay, she came out of the Rift Valley, right? Yeah, so she's one of the earliest, let's say, full skeletons that we've ever found. So it's not just a head, and it's not just a tooth. You can kind of see the whole thing. I mean, it was a really big deal, and it's just been 50 years since that discovery, actually. Wow. And it was named after his wife?
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
It was named after Lucy in the Sky of the Diamonds, which was playing on the radio as they were excavating. Louis Leakey?
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
No, no, no. This is up in Ethiopia, and they named Lucy after the song, Lucy in the Sky of the Diamonds.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Australopithecus methamphetamine never caught on.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
But again, I mean, it's still very ape-like as far as we can tell in terms of diet and stuff, eating almost all plants. There's some interesting ideas these days that they might've had some very simple tools maybe, but things don't really shift away from like an ape-like kind of way of life until you get hunting and gathering going two and a half, two million years ago. And we get fired as well.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
So that doesn't show up until about a million years ago. There's a gap. So there's about two and a half million years ago, we start hunting and gathering. And that changes everything because, I mean, just think about what it means to have a species that does two different things. No other species does that. There are species that kind of generalize any individual bear, for example.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
We'll eat fruits and we'll hunt a little bit and... So they're generalists. Yes. But there's no other species that half of the group does one thing, acts like a carnivore. The other half acts like an herbivore and gets plant foods. And then so you get the advantages of both. Then you have to share it. Yeah. Animals don't like to share, right? Very rarely. And in fact, even apes don't share much.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Well, for sex trade, they do. Yeah. Very specific context. Yeah. And very little in terms of total amounts.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Yeah, social carnivores, that's another example. Wolves. But that's how rare it is. You can kind of think of specific examples. Almost every animal just keeps it. That's what usually works the best. Yeah.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
That has permeated everything, so... I come in here and I don't know you guys, but you don't kill me. That's crazy. That is nuts. And then you offer me food. Wow. Think about that. And anytime you have a celebration, you're sharing food. That's the fabric of what humans are all about. And then what's fun about that is it's just the snowball of...
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Social complexity, intellectual complexity, all of a sudden brains are not just figuring out where the food is and not just figuring out maybe who to mate with, but they're doing all these calculations about who's in my group, who's a friend, who's an ally, who I can trust, who I can't trust. Then you have all the forging stuff on top of that and the complexity just snowballs.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
And you see the tools develop with that. So over the past 2 million years, you can like literally track from simple stone tools to more complex to multi-piece tools to iPhones.
Armchair Expert with Dax Shepard
Herman Pontzer (on evolutionary anthropology)
Easiest way to track that would be size dimorphism. So in a gorilla, for example, males are twice as big as females. And it's because they basically just fight over who has access to the group of females.