Joe Rogan Experience #1201 - William von Hippel

1. 0:01 – 0:18

   Book premise: how humans became human through a “social leap”

   1. JRJoe Rogan0:01

      All right, here we go. Four, three, two... (hands thwack on desk) Hello, Bill.

   2. WHWilliam von Hippel0:08

      Hi.

   3. JRJoe Rogan0:09

      What's going on, man?

   4. WHWilliam von Hippel0:10

      I am very excited to be here.

   5. JRJoe Rogan0:11

      I'm excited to have you here.

   6. WHWilliam von Hippel0:12

      Excellent.

   7. JRJoe Rogan0:12

      Um, The Social Leap.

   8. WHWilliam von Hippel0:14

      Yes.

   9. JRJoe Rogan0:14

      What's The Social Leap?

   10. WHWilliam von Hippel0:16

       I'll tell you all about it.

   11. JRJoe Rogan0:17

       Please do.

2. 0:18 – 3:25

   The Great African Rift Valley and the push out of the rainforest

   1. WHWilliam von Hippel0:18

      Okay. So, um, the story that I wanna tell is basically how we got here, how we became human. And so, that story begins about six or 7 million years ago, when our ancestors left the rainforest. And so, the question is, why would they leave and how would they survive once they left? And, and that's what The Social Leap is. So it takes a second to get it all out there, okay?

   2. JRJoe Rogan0:40

      Yeah.

   3. WHWilliam von Hippel0:40

      All right. So here's the story. (smacks lips) So if you look back about seven million years, our ancestors and chimps, we had a common ancestor at about that point in time, six or 7 million years ago. And that common ancestor, we don't know exactly what it looked like, but it was... from all we can tell, it was awfully close to today's chimps. And so there... if you look at chimps today, you can get a pretty good sense of what life was like then. And chimps today are really interesting. They're basically at the top of the food chain in the rainforest. They're super fast up in the trees, super athletic, and (stutters) because they travel in groups, even amazing tree climbers like leopards won't try to attack them in trees. It's just... they would-... it's-... they're too dangerous, too fast. But if you look at a chimp on the ground, it can't even lock its knees. It's this kinda cute little stumbling along thing. And then the question is, why would an animal that runs the show in the canopy leave the rainforest for the savanna, and then how would it survive once it did that? A- and that's, that's the story of this book, and then how that manifests itself to where we are today. So really, my goal, I'm a psychologist. I wanna understand why we are the way we are. And so, in trying to figure that out, I said, "Well, let's take a look back all the way to our common ancestors and see some of the key events and how they might have had an influence on how we are today." So the first question is, why would we leave the trees, right? Here we are. We're dominant position. We're, we're food on the ground. Why would we ever take that risk? And the basic story there is the Great African Rift Valley. I'm not sure if you've-... if you're familiar with it at all. But basically, it runs down from, um, up at the Red Sea down to the coast of Mozambique. And you can think of it like a geographic zipper. You know, all the world sits on these tectonic plates, and sometimes they crash into each other, like, uh, how India's smashing into Asia and creates the Himalayas. Sometimes they literally tear apart, and Africa's tearing apart at the Great African Rift Valley. So that plate that has Somalia and Ethiopia, Tanzania, Kenya, that's moving off to the lower right. The rest of Africa is moving off to the upper left. And (smacks lips) I got no d- no idea why. It's been going on for quite a while. But one of the consequences of that is that the... East Africa's starting to rise up slowly bit by bit, and when it rises up, the rainforests dry out. And so basically, what you have is a situation where our ancestors were on the east side of that rift valley and it started to dry out, and now they're in a situation where they've got this great lifestyle, they're a dominant position, but now they're pushed... they're forced out onto the ground increasingly more and more because there's more and more ground and less and less rainforest. And so how do they survive that? What do they do in order to make that work?

   4. JRJoe Rogan3:10

      And this is, uh... What, what period of time is this? How many millions of years ago?

   5. WHWilliam von Hippel3:14

      (smacks lips) Six or 7.

   6. JRJoe Rogan3:15

      Six or 7. Does this coincide with the l-... When, when was the jump of the human brain size, where it doubled-

   7. WHWilliam von Hippel3:22

      Oh, we'll get to that. So-

   8. JRJoe Rogan3:23

      Okay, but-

   9. WHWilliam von Hippel3:23

      ... i- it's a super interesting question about-

   10. JRJoe Rogan3:25

       Mm-hmm.

3. 3:25 – 5:02

   Early savanna living: group size, sharing, and the Australopithecus plateau

   1. WHWilliam von Hippel3:25

      ... why that happened as well. So basically, if you track us across the next three million years, how did our ancestors survive when they're basically chimpanzees on the open savanna? And you can get a hint of how they did it, because there's one chimpanzee group that does live on the savanna in Senegal, and they, um, they show some differences between themselves and other chimps. They travel in slightly larger groups. They share more nicely with each other, which is interesting. That's kind of a human trait as well. And, uh, they also avoid open space. Like, they're just kind of s-... trying to stay near the trees as much as possible. And so... (smacks lips) And if you look at other apes, they're... not apes, but other primates that are on the savanna, like savanna baboons, they're only monkeys, so they're not as sharp as chimpanzees are, but they have a similar strategy, large groups to try to protect themselves and lots of eyes to look out for predators. And they do fine on the savanna. And so what I suspect happened is for the first few million years, basically what you've got is this chimp-like animal that's kind of skirting the edges of savanna, nowhere near the top dominant position they used to be, and just kind of noodling around. And that takes... I suspect that takes us for about the first three, three and a half million years. And if you look at who we are then, we're Australopithecus afarensis. So it's... if you looked at one of them, you'd think it belongs in a zoo. It looks almost like a chimpanzee. And so a chimp brain, in answer to the first part of your question, is about 380 grams, and an Australopithecus brain is about 450 grams. So three million years of evolution, and all we've got for it is 70 grams. So (smacks lips) why did we get so smart? Why did we take off in the next few million years? And what is it that Australopithecus did that, that helped us survive? And, and why do I call that the social leap?

   2. JRJoe Rogan5:02

      Mm-hmm.

4. 5:02 – 7:44

   Bipedalism as an accidental gateway to throwing and distance killing

   1. WHWilliam von Hippel5:02

      That's all kind of tied together. And the basic story is that by this point, Australopithecus has become bipedal. And we can talk about how that happened, if you'd like. And so, because they're bipedal, their waist is now stretched out. Their, um, their musculature, like if you look at chimpanzee pecs, they aim upward because, of course, chimps climb all the time. Um, Australopithecus is more lateral, like we are. We're basically completely lateral, because things are side to side as far as we're concerned. It's harder to climb a tree, but it's a whole lot easier to do a lot of other things. And, um, (smacks lips) we have a much more limber shoulder. We have much more limber wrists, all that sort of thing. And a lot of that was in place by Australopithecus. So once they became bipedal, they gained a lot of these qualities. And then the question is, why do those qualities matter? Well, the... if you watch a chimpanzee throw, it's terrible at it. Even though they're stronger than you and I are pound for pound by a sizeable margin, when they throw, they're inept. They can't aim very well, and they typically use two hands, because they're not lined up well to throw. If you watch a really good thrower, like, y- you know, a gridiron... a, a football player, baseball player or hunter-gatherer throw, you know, it's a full body motion, step forward with the other leg. There's this rotation, and the very last minute, you bring your wrists through. Well, what that does is it creates an enormous amount of elastic energy across your muscles, tendons and ligaments. And the end of that throw for a human is like the snapping of a rubber band. So-Chimps can't do that. They're not lined up properly. But australopithecus got to the point where they could probably do that pretty well. And so now, and this purely a byproduct of bipedalism, because it stretched out their whole body and they don't, they're not climbing as much anymore, so their musculature is more lateral, which would have been helped them for throwing. So now you get to a point where they have access to the single most important military invention in history, which is the capacity to kill at a distance. So if you and I are running around the savanna and a lion attacks us, and we got 50 of our best friends, we could kill it with our bare hands, but a lot of us are going to die in the process, right? 'Cause-

   2. JRJoe Rogan7:01

      You think 50 of us could kill a lion?

   3. WHWilliam von Hippel7:03

      I, let's make it 100. The, if someone-

   4. JRJoe Rogan7:05

      You really think even 100 of us could kill a lion? (laughs)

   5. WHWilliam von Hippel7:07

      (laughs) It would, you know, with a bunch of knives and shit.

   6. JRJoe Rogan7:08

      If I was a lion, I'd be super confident-

   7. WHWilliam von Hippel7:10

      Yeah, you, you wouldn't worry.

   8. JRJoe Rogan7:11

      ... about fucking up our other people.

   9. WHWilliam von Hippel7:12

      Y- you wouldn't worry very much, but-

   10. JRJoe Rogan7:13

       (laughs)

   11. WHWilliam von Hippel7:14

       But even if we could, so we knew what we're doing, we were all armed with knives-

   12. JRJoe Rogan7:17

       Right.

   13. WHWilliam von Hippel7:17

       ... whoeve- whoever goes in s- first is screwed.

   14. JRJoe Rogan7:19

       Right. Right.

   15. WHWilliam von Hippel7:19

       And so, the capacity to kill at a distance though allows a larger force of weaker individuals to com- to easily defeat a stronger individual.

   16. JRJoe Rogan7:27

       Right.

   17. WHWilliam von Hippel7:27

       And so once they gain this capacity to throw, if they were attacked by lions or something like that, whereas in the past they'd have just scattered for the trees, now they could throw stones at it and defend themselves.

   18. JRJoe Rogan7:37

       Mm-hmm.

   19. WHWilliam von Hippel7:37

       Now, an Australopithecus throwing rocks at a lion is going to be in the belly of a slightly annoyed lion in about three minutes, right?

   20. JRJoe Rogan7:44

       Right.

5. 7:44 – 12:11

   The “throwing hypothesis”: collective action becomes individually rational

   1. WHWilliam von Hippel7:44

      But 50 Australopithecines throwing rocks at lions is a totally different story. And so it's the, this is the, the idea here is the throwing hypothesis. That what-

   2. JRJoe Rogan7:53

      Mm-hmm.

   3. WHWilliam von Hippel7:53

      ... what changed everything was throwing, and the reason it changed everything is that it caused us, it, it was the first reason why we should have any effective collective action. Because it's not a good strategy when you're on your own, it's not a good strategy if I do it and the rest of the group hits, heads for the trees, but it's a great strategy if we all do it together.

   4. JRJoe Rogan8:10

      Hmm.

   5. WHWilliam von Hippel8:11

      And so for the first time in history, the group's goals, i- in our history, in our line, the primate line, the group's goals aligned with the individual goals, which is, let's cooperate and work together to try to drive away these predators.

   6. JRJoe Rogan8:23

      Hmm.

   7. WHWilliam von Hippel8:24

      Now, it, if you look at a lion and you look at someone throwing rocks, it still seems like a really big ask, right, to, to drive that thing away or kill it throwing rocks. And so, but, um, Barbara Isak, who was one of the first anthropologists to propose this hypothesis quite a while ago, went back and looked through the historical record and these extraordinary stories of how effective people are throwing rocks. And so in, when, um, the Portuguese went to the Canary Islands to try to subjugate it, they rock up with, you know, armor, guns, uh, crossbows, and this is in the, like, 14-something, and all the locals were armed with was stones. And despite the fact that the Portuguese are there in army, trained, you know, ready to shoot and, and in their armor, they were just decimated by the locals throwing rocks at them. And this story's happened over and over again, and when you read these accounts, they're extraordinary. I can read you some examples from here. They just, the, it happened in Australia, it happened in the Canary Islands, it happened elsewhere. They just throw rocks incredibly accurately, incredibly hard, and really fast.

   8. JRJoe Rogan9:21

      Hmm.

   9. WHWilliam von Hippel9:22

      So, and there's, you know, accounts in Africa, m- uh, basically killing a zebra with one blow of a rock to the head.

   10. JRJoe Rogan9:28

       Hmm. So like a, a pitcher, a major league pitcher-

   11. WHWilliam von Hippel9:33

       Yeah. Exactly.

   12. JRJoe Rogan9:33

       ... with a good rock-

   13. WHWilliam von Hippel9:35

       Right.

   14. JRJoe Rogan9:35

       ... who, who gets very accurate at it.

   15. WHWilliam von Hippel9:37

       Yeah.

   16. JRJoe Rogan9:37

       So do you think they, they must have practiced?

   17. WHWilliam von Hippel9:40

       Constantly.

   18. JRJoe Rogan9:40

       Yeah.

   19. WHWilliam von Hippel9:41

       And so what I suspect is that we evolved to like to throw rocks. And so if I look at-

   20. JRJoe Rogan9:44

       Wow.

   21. WHWilliam von Hippel9:45

       ... if you look at my son as a for example, when he was 18 months old, we would be walking back toward the house. If he saw a rock on the street, he'd pick it up and start trying to throw it.

   22. JRJoe Rogan9:53

       Hmm.

   23. WHWilliam von Hippel9:53

       And my wife is like, "No, no, no, don't let him throw rocks. It's only going to cause trouble." At first of all I'm thinking, "Well, maybe he'll develop a good arm, so I'm going to go ahead and let him anyway."

   24. JRJoe Rogan10:00

       (laughs)

   25. WHWilliam von Hippel10:00

       But, but secondly, he fricking wants to. This is like something inherently fun for him.

   26. JRJoe Rogan10:04

       Right. Right.

   27. WHWilliam von Hippel10:05

       And I think all humans enjoy throwing, and it's, it's stunning how good you can get it with practice. So, um, we were at the Ohio State Fair, this was before my son was born, and I was walking by, uh, one of these stalls where you can throw in a radar gun, and so I thought, oh, here's ... I, I was just starting to date my wife and I thought, "Oh, here's a perfect chance to impress her, right? And how, how macho I am." So I said, "Hey, why don't I stop and I'll throw some balls here in this net?" 'Cause I had never thrown, I didn't know how fast I could. So she's like, "Sure." And I was, I played like Little League, right? So I, I throw the ball and it's like 50 miles an hour. And, and she's pretty impressed because that's sounds fast, right? And then this like kid shows up next to me, he's got to be 12 years old, probably weighs 85 pounds, this total dangle, not a muscle in his body, and he just starts fricking throwing ball after ball at like 65 miles an hour. And I'm like, "Fuck." I mean, she's not going to be impressed-

   28. JRJoe Rogan10:53

       (laughs)

   29. WHWilliam von Hippel10:53

       ... with this like human twig next to me-

   30. JRJoe Rogan10:55

       Yeah.
6. 12:11 – 15:20

   Why bigger brains became worth the cost: genes, energy, and coordination

   1. JRJoe Rogan12:11

      Right.

   2. WHWilliam von Hippel12:11

      ... it's constant drain. And so what are our ancestors, why would they pay for that drain? Now, just recently, there was a paper that came out maybe three months ago now on, um, a new brain expansion gene they found, or they think that's what it is called Notch2NL, and it turns out-... I don't know, 12, 15 million years ago, there was an accidental duplication of that gene on our genome. And it ... But it was ineffective and it just sat there doing nothing. Now, that's a great way that evolution works, where it accidentally doubles a gene, because then you don't ... You can mess with it and the old gene's still doing the job, right?

   3. JRJoe Rogan12:41

      Mm-hmm.

   4. WHWilliam von Hippel12:42

      So it sat there for about nine million years in our line, till about three million years ago, around Australopithecus. And then it duplicated itself and it came online again. And what that gene seems to do is it makes our brain remain as stem cells for longer, which means a lot more duplication before they run away and start becoming neurons.

   5. JRJoe Rogan12:58

      Mm.

   6. WHWilliam von Hippel12:59

      And so if I had to guess, I'd say that that probably ... That gene coming online probably happened many times in the past, and every time it happened in the past, it was more cost than it was worth. And so what's a chimp gonna do with a little bit more brain and ... Just means more calories and what does he gain from it? But now that we're working together, now that we have collective action, all sorts of things open up. We could, we could devise division of labor. I'll say, "Hey, man, you do this and I'll do that." 'Cause Australopithecus, they've got 70 more grams than a chimp. They can't do things like that. But they can all throw rocks at the same time, that's not rocket science. But all the kinds of things that came next probably were enabled by that process of us coming together and deciding to work together and cooperate. So if you look at chimpanzees, they don't cooperate very well. Um, for example, one of the activities where they sort of cooperate is when they hunt monkeys. And so they'll all gather round and they'll see some monkeys in the trees and they come in from every angle. It's not very coordinated, it's kind of a wild free-for-all. But what's interesting about it is that when the hunt's over, let's say you just sat there the whole time and watched and I'm working my ass off chasing these monkeys. I got one, you come up and bug me for it, and I don't, I don't willingly handle it. You like keep nudging me till I share, but I'm just as likely to share with you if you helped as if you didn't.

   7. JRJoe Rogan14:11

      Mm.

   8. WHWilliam von Hippel14:11

      I don't make any distinction. And you'll never establish effective groups if you can't reward those who participate compared to those who don't.

   9. JRJoe Rogan14:18

      Mm.

   10. WHWilliam von Hippel14:18

       Even little kids, four-year-old kids, when you give them games to play and they earn stickers, if you didn't play, you don't ... When you come up and ask, you don't get any. You played, even if you didn't do your job right but you tried, boom, you can have a sticker. So humans immediately get that, that you get rewarded for your activities as part of the group. Chimps don't seem to have that.

   11. JRJoe Rogan14:36

       That's fascinating, 'cause ... But ... Because chimps really do have a sense of fairness though, and that, that's one of the issues ...

   12. WHWilliam von Hippel14:44

       Yeah.

   13. JRJoe Rogan14:44

       ... that happened with the, the captive chimp that attacked the man who brought the birthday cake. Do you know that story?

   14. WHWilliam von Hippel14:48

       I don't know that story.

   15. JRJoe Rogan14:49

       Awful story.

   16. WHWilliam von Hippel14:50

       Oh.

   17. JRJoe Rogan14:50

       These, this couple, um, they kept a chimp as a pet for a long time, and then as it got older, it got a little violent and they had to bring it to a sanctuary. And they brought it to a sanctuary and they would go to visit it, and the chimp would remember them, and they went to visit it and it was on its birthday, so they brought him a cake. And the other chimps in the sanctuary were furious that they didn't get the cake, uh, as well.

   18. WHWilliam von Hippel15:11

       Yeah.

   19. JRJoe Rogan15:11

       They didn't think it was fair or they were angry.

   20. WHWilliam von Hippel15:13

       Yeah.

   21. JRJoe Rogan15:13

       So they figured out somebody had left the gate open and they got out and tore this guy apart ...

   22. WHWilliam von Hippel15:18

       Yeah. So-

   23. JRJoe Rogan15:19

       ... because he didn't give them a cake.

7. 15:20 – 18:58

   Fairness, envy, and status: what primate ‘inequity’ reactions really mean

   1. WHWilliam von Hippel15:20

      Yeah, so there's a m- the, the most famous example of that is actually with Capuchin monkeys, which aren't nearly as smart as k- chimps. And it's this amazing study by Sarah Brosnan and Frans de Waal. And if you wanna see it in action, de Waal has it on a TED Talk. It's really quite something to see.

   2. JRJoe Rogan15:33

      Mm.

   3. WHWilliam von Hippel15:33

      And what they do in that study is they teach these Capuchin monkeys to ... They, they give them pebble, and they teach the Capuchins to return the pebble and they give it a cucumber slice. And so it's learned the game for cucumber slices. So if, if you wanted to ask, "Does the monkey think that's a fair reward?" The answer has to be yes, right?

   4. JRJoe Rogan15:49

      Mm-hmm.

   5. WHWilliam von Hippel15:49

      'Cause it's, it's doing that for cucumber. So now you and I are both monkeys and we're in our cage. I return the pebble, I get a cucumber. Now you return the pebble and they hand you a grape. Capuchins much prefer grapes over cucumbers. And so then you ... What happens next? Well, I've been doing this behavior for cucumbers, but as soon as you get a grape, I'm like, "Yeah, I'm not playing anymore." And you watch this tape and the Capuchin, it, uh, th- they give you a grape, they give me the cucumber, and the thing looks totally pissed. It starts pounding on the ground, it throws the cucumber back at the experimenter.

   6. JRJoe Rogan16:17

      Whoa.

   7. WHWilliam von Hippel16:17

      It's amazing, yeah?

   8. JRJoe Rogan16:18

      (laughs) Whoa.

   9. WHWilliam von Hippel16:19

      And so the question is, what does that mean? Why do they care about fairness in that way? And, and I think the answer to that question is sexual selection.

   10. JRJoe Rogan16:26

       Oh.

   11. WHWilliam von Hippel16:27

       And so the key to sexual selection is, it doesn't matter what everybody's getting so long as I'm getting about as much as everybody else. But at the second that you're starting to get more than I h- have, well then whatever female's in our group, she's gonna pick you before she picks me.

   12. JRJoe Rogan16:41

       Mm.

   13. WHWilliam von Hippel16:42

       And so everything is relative. We may think, you know, why do you care so much about what other people are doing? Why don't you just be happy with what you got? But literally the day you find out that the guy in the next studio over's salary's twice yours, your salary sucks.

   14. JRJoe Rogan16:55

       Right.

   15. WHWilliam von Hippel16:55

       Because e- ... And it, it makes sense, because literally, sh- she's gonna choose him now before she chooses you.

   16. JRJoe Rogan17:01

       Comparison is the thief of joy.

   17. WHWilliam von Hippel17:03

       Yeah, that's exactly right. It's a-

   18. JRJoe Rogan17:04

       Yeah.

   19. WHWilliam von Hippel17:04

       It's a really unfortunate fact, because ... And sometimes it matters a lot. Like, for example, imagine I invent a drug and I say, "Here, take a dose and it'll double your IQ." Instantly, you're gonna feel like a genius. But unbeknownst to you, I gave everybody two doses.

   20. JRJoe Rogan17:17

       Wow.

   21. WHWilliam von Hippel17:17

       You walk out of there, you're gonna feel like a dumbass, because there's ... People are saying stuff you can't understand, right?

   22. JRJoe Rogan17:21

       (laughs)

   23. WHWilliam von Hippel17:22

       So then it would matter.

   24. JRJoe Rogan17:23

       Right.

   25. WHWilliam von Hippel17:23

       But the, the killer cases are things where, where it's only just a residue. So for example, there's this amazing study where they showed that people who are making minimum, just above minimum wage are the ones who don't want you to raise minimum wage. They're the most against it.

   26. JRJoe Rogan17:37

       Really?

   27. WHWilliam von Hippel17:37

       Yeah. Now why would that be? Well, right now they've got a slight advantage over people making minimum wage. The day minimum wage gets raised, now they're not any better off than anybody else. So even though they're the most likely to benefit from it because they may lose that job they have and have to take minimum wage, they're actually against it because it gives them a slight advantage over, you know, the guy next door.

   28. JRJoe Rogan17:57

       Is this based on one study? 'Cause I would think that the people that would be most against it would be the people that are hiring folks.

   29. WHWilliam von Hippel18:03

       All right, fair enough. Uh, it's only, uh, it's only looking at income, so the, the boss probably feels even the more negative of all.

   30. JRJoe Rogan18:09

       Yeah.
8. 18:58 – 34:30

   Mating systems and jealousy: pair bonding, bonobos, and why Sex at Dawn is disputed

   1. WHWilliam von Hippel18:58

      Well, here's the thing.... um, it depends on whether your mating system is gonna be pair bonding or not.

   2. JRJoe Rogan19:04

      Hmm.

   3. WHWilliam von Hippel19:04

      So, if you're a frog or a, um, lots of different frogs, not all of 'em, a laughing tree frog, or if you're a elephant seal or something, well, all the females mate with the best male, 'cause his job is just sex. And so every female can have the best one, or the, e- either in a situation where they got no choice, like the elephant seals, he controls the rookery-

   4. JRJoe Rogan19:23

      Right.

   5. WHWilliam von Hippel19:23

      ... or in a situation where they just listen to all the croaking and then they go, "All right. You're the best croaker. You're the dad."

   6. JRJoe Rogan19:28

      Hmm.

   7. WHWilliam von Hippel19:28

      But if you're pair bonding like humans or like lots of other animals, birds, et cetera, the, then what you need is you've got competition on both sides. So she's always competing to get the best male and he's always competing to get the best female. Now, there's reasons why male-male competition is always a bit more intense than female-female competition, but both of them are there. And the more monogamous the system gets, the more both sides compete for each other.

   8. JRJoe Rogan19:54

      Hmm. Interesting. So what about in the case of, like, bonobos where they're so polyamorous?

   9. WHWilliam von Hippel20:01

      Bonobos are super interesting systems. So you got lots of polyamorous animals. Um, bonobos are interest- they're, chimps are also, you know, so if you look at a-

   10. JRJoe Rogan20:09

       Mm-hmm.

   11. WHWilliam von Hippel20:10

       Eh, one of the great ways to look at our ancestors and what their lives were like is you look in your trousers. And the size of your testicles tells you a lot about what sort of m- mating system your ancestors had. So gorillas have tiny little testicles. And the reason that they have such tiny testicles is they use their huge body to drive away the other males, and then all the females are in his harem. So he doesn't need big testicles because he only needs enough sperm in order to inseminate the females he's got. It doesn't take much sperm to inseminate any one female, and testicles are really expensive tissue to make. And if you own a pair and you land on 'em, you know they're uncomfortable too, right? And so then you look at our testicles, and they're quite a bit bigger than a gorilla's, but they're nowhere near the size of a chimp, uh, or bonobo both. You know, they're basically in many ways almost the same beast. And so... although socially quite different. And, um, they have a system where they basically have to wash out the guy who was there before 'em, and so it takes really big testicles to have sperm competition. So their competition isn't by fighting each other, although there's a degree of that too. They know full well that when she comes into estrus, into heat, there's gonna be a line and, and if you're fifth in line and you can wash everybody out before you-

   12. JRJoe Rogan21:15

       Right.

   13. WHWilliam von Hippel21:15

       ... you might end up the dad.

   14. JRJoe Rogan21:16

       Wash everybody out is a funny way of putting it.

   15. WHWilliam von Hippel21:18

       Yeah.

   16. JRJoe Rogan21:18

       So they-

   17. WHWilliam von Hippel21:18

       It's not very romantic.

   18. JRJoe Rogan21:19

       (laughs) It's, uh, this, this testicle size is directly proportionate to the number of promiscuous females.

   19. WHWilliam von Hippel21:26

       Well, that's-

   20. JRJoe Rogan21:27

       That's-

   21. WHWilliam von Hippel21:27

       Right. The promiscuity of the mating system.

   22. JRJoe Rogan21:29

       Yes.

   23. WHWilliam von Hippel21:29

       And so if you look at our mating system, we clearly evolved to be largely monogamous, but not entirely. Our testicles are unnecessarily large for, for an entirely monogamous species. And so we are a little bit on the wash the guy out ahead of us domain.

   24. JRJoe Rogan21:42

       But, uh, b- there's many people that make arguments that our monogamy is socially reinforced and it's not natural.

   25. WHWilliam von Hippel21:48

       Look, if you look at hunter-gatherers and, and so the best, the best way that we get a sense of, well, what, what did we evolve to do is to look at the remaining hunter-gatherer societies.

   26. JRJoe Rogan21:57

       Mm-hmm.

   27. WHWilliam von Hippel21:57

       Particularly if you look at what are called immediate-return hunter-gatherers. So they're people who eat today what they killed today. Now, you got a lot of hunter-gatherers once they left the equator, they could store food and, and everything changed for them. And they actually, in many of their behaviors, they look a lot like us. And we can come back to that if you'd like. But if you look at hunter-gatherers around the equator, they're typically immediate-return, kill, eat. And so those guys, um, tend to be, tend to be, there's always, of course, human differences, we're a super variable species, but they tend to be serially monogamous. And so some people pair up for life. Lots of people pair up for five, seven years and then break apart and pair up again-

   28. JRJoe Rogan22:34

       Mm-hmm.

   29. WHWilliam von Hippel22:34

       ... and so you have sequence of children with a sequence of people.

   30. JRJoe Rogan22:37

       Right.
9. 34:30 – 41:12

   Jealousy research and testosterone debates: what data can (and can’t) show

   1. WHWilliam von Hippel34:30

      Um, the social leap that I'm arguing about is not this pair bonding thing. It's about how our groups came together to engage in collective action. So, in principle, I'm agnostic on this issue. I just happen to disagree with that. I happen to feel like, no, I think we made these deals. And so to c- come back to the study that David Buss did that I was starting to tell you about. So Buss has this, um ... He's got ... When he came along, people thought that the two sexes had similar levels of jealousy for infidelity. And David was like, "Well, look, s- insemination's internal and so men should be a lot more worried about, uh, her sleeping with somebody else than women should be." Because he ... Men never know for sure if they're the father. They can't see it happen. Whereas, you know, if you're a sam and you can say, "Okay, I'm the dad. I just watch that." But, um, females, they ... Be- ... Insemination's eternal, but they know they're the mother. That's not their concern. They should be more concerned about things like, um, his giving her resources to help her raise the kid and things like that. And so what Buss found is if, if you ask people this question, what would bother you more? Imagine your wife having sex with somebody that she just met for the first time, having this great time and doing all these different funky things with him and then never doing it again. Or your wife develops this, you know, ongoing emotional connection with somebody. She never touches him, he never touches her, but she ... They talk and have ... Share their feelings and stare deep in each other's eyes. What would bother you more? And you ask men and women that question.

   2. JRJoe Rogan35:53

      Hmm.

   3. WHWilliam von Hippel35:53

      So what would ... In your case, what would bother you more, to have your wife to know she had this one-off affair, fling, sex only, didn't care about the guy, or she develops this sort of emotional bond with somebody, never touches him?

   4. JRJoe Rogan36:06

      That's a good question. I'd really have to think about that. I don't know. (laughs)

   5. WHWilliam von Hippel36:08

      It's not an easy one 'cause nobody likes either of them.

   6. JRJoe Rogan36:11

      No. Yeah. Because, uh, it's a matter of time before that dude gets in that's a-

   7. WHWilliam von Hippel36:16

      (laughs) No.

   8. JRJoe Rogan36:16

      ... fox hanging around the chicken coop.

   9. WHWilliam von Hippel36:16

      No, it's a guarantee. I know, but it's ... In this case, it's a guarantee, right?

   10. JRJoe Rogan36:19

       (laughs)

   11. WHWilliam von Hippel36:19

       Yeah.

   12. JRJoe Rogan36:19

       It's a guarantee that they never hook up.

   13. WHWilliam von Hippel36:20

       Never touch. Never touch.

   14. JRJoe Rogan36:21

       As long as he doesn't talk shit about me.

   15. WHWilliam von Hippel36:23

       (laughs)

   16. JRJoe Rogan36:23

       That's the problem. Those guys, they have the poisoned tongue.

   17. WHWilliam von Hippel36:26

       Try to like wedge you away, right?

   18. JRJoe Rogan36:26

       Yeah. They said that, "Well, I would do so much better."

   19. WHWilliam von Hippel36:29

       (laughs)

   20. JRJoe Rogan36:29

       This guy just doesn't treat her right.

   21. WHWilliam von Hippel36:31

       Right. Well, here's the thing.

   22. JRJoe Rogan36:31

       Those little weasels.

   23. WHWilliam von Hippel36:32

       Yeah. On average-

   24. JRJoe Rogan36:34

       (laughs)

   25. WHWilliam von Hippel36:34

       ... men are more bothered by sex, the one-off sex.

   26. JRJoe Rogan36:37

       Ah.

   27. WHWilliam von Hippel36:37

       And, and women are more bothered by the-

   28. JRJoe Rogan36:39

       Emotional connection.

   29. WHWilliam von Hippel36:39

       ... emotional connection 'cause that's a bigger threat.

   30. JRJoe Rogan36:41

       Because emotional connection could lead to him leaving her.
10. 41:12 – 44:05

    Homo erectus: brain doubling, cooking, and the leap to sophisticated tools

    1. JRJoe Rogan41:12

       Ah, whatever. Um, so when these chimp-like creatures from millions of years ago slowly started walking upright and started, uh, moving into the grasslands-

    2. WHWilliam von Hippel41:25

       Right.

    3. JRJoe Rogan41:26

       ... and making, uh, making experiments and traveling away from the jungle, um, and this coincided with the development of the throwing arm and this could... Because they started walking upright, um, when did this... when did the cooked meat aspect come a-

    4. WHWilliam von Hippel41:42

       Okay.

    5. JRJoe Rogan41:43

       ... come along?

    6. WHWilliam von Hippel41:43

       So they don't control fire.

    7. JRJoe Rogan41:45

       Right.

    8. WHWilliam von Hippel41:45

       So Australopithecines can't do that. So now we go for- we're now about three and a half million years ago. You got to now go forward to about al- a little less than two million years ago to get to Homo erectus. So once we get to Homo erectus, we now got an, uh, an ancestor that literally if it went to the zoo, you'd say, "Well that's a kinda rough-hewn guy."

    9. JRJoe Rogan42:02

       Right.

    10. WHWilliam von Hippel42:02

        But you'd think it's a person and not somebody-

    11. JRJoe Rogan42:05

        Mm-hmm.

    12. WHWilliam von Hippel42:05

        ... who b- belongs behind the glass.

    13. JRJoe Rogan42:06

        Right.

    14. WHWilliam von Hippel42:06

        So, so a chimp brain is 380, Australopithecus 450, and Homo erectus 960.

    15. JRJoe Rogan42:12

        Whoa.

    16. WHWilliam von Hippel42:13

        So you got doubling of brain size. Now mind you, it's a bigger being, so you're go-

    17. JRJoe Rogan42:16

        Right.

    18. WHWilliam von Hippel42:16

        It's not as quite as big or dramatic of a change as you think. But along with that comes all sorts of capabilities. Now you write about this book, Catching Fire. Richard Wrangham argued that what enabled that... So if you look at the gut of a gorilla or a chimpanzee and their brain, they got a lot of gut for a little bit of brain, because it takes a lot of digestion to keep the little bit of brain going. We have a tiny gut for a huge brain. And Wrangham argues, and I think quite rightly, that the only way you can achieve that is by releasing more nutrients from your food and the only way you can release more nutrients from your food is by cooking it. So when he made that argument, he thinks it goes back to the beginning of Homo erectus and I suspect he's right. At this point, when he made the argument, we- it was only back to, I don't remember, half a million years, 300, 750,000. It's already back to a million years ago, we found in caves in South Africa evidence of controlled fire.

    19. JRJoe Rogan43:03

        Mm.

    20. WHWilliam von Hippel43:04

        And so it'll probably keep getting pushed back, 'cause you know that crap's hard to find.

    21. JRJoe Rogan43:07

        Right. So this was, did you say half a million years?

    22. WHWilliam von Hippel43:09

        No, now it's back to a million years ago.

    23. JRJoe Rogan43:11

        A million years. So a million years ago-

    24. WHWilliam von Hippel43:11

        And he made that prediction when it wasn't even that far back.

    25. JRJoe Rogan43:14

        And a million years ago, even though they're, they're not technically... It's not Homo sapien.

    26. WHWilliam von Hippel43:18

        No. We're still at Homo erectus.

    27. JRJoe Rogan43:19

        Yeah. Right.

    28. WHWilliam von Hippel43:20

        And so they started at 1.9 or so, 1.7 million years ago. And 1.9, I think. And what Homo erectus could now do... So now remember what the argument is, is this social leap, it's this collective action that not only, um, protects us on the savanna, but sets us on this new pathway. It creates this new niche. It's this cognitive niche, although I think of it as a social cognitive niche because it's the working together that gives you all these potential advantages to getting smarter.

    29. JRJoe Rogan43:47

        Hm.

    30. WHWilliam von Hippel43:47

        And so now that when that gene's sitting in our head, if it kicks into gear, those... And starts to work and, and it cre- leads to cranial expansion, those animals who have it will have an advantage 'cause they can coordinate with each other better.
11. 44:05 – 49:49

    Division of labor, hunting big game, and the archaeological hints of coordination

    1. WHWilliam von Hippel44:05

       They could do a lot of things with that brain power. And by the time you get to Homo erectus and the brain power is doubled, we see all sorts of super interesting things. So before Homo erectus, when you look at our tools, they... It's called an Oldowan tool and it's basically a barely sharpened rock. And you never find an Oldowan tool-... too very far away from where it, it was quarried and made. Like, you know, you'll, you look at the rock and the chips and not far away is where it's lying on the ground. Homo Erectus made a much nicer tool. It's bifacial. It took a lot of energy to make it. Um, when, when we teach modern anthropologists or grad students or whatever to make them, and you put them in an fMRI magnet where it can measure m- m- metabolism in your brain as you go, you see that it takes a lot of frontal lobe functioning in order to make one, because it's a lot of planning. "How am I gonna hit it next to make this thing just right?" Compared to an Oldowan tool, to make those doesn't take much frontal function. "Ah, I just whack it there and it'll be sharp." And so, the, so first of all, we know Homo Erectus invented that tool. This, this Acheulean tool with this bifacial hand ax. Um, second of all, and, and one of my, one of the coolest findings, there's some interesting work in a 1.2 million-year-old site in India, uh, by Kerry Shipton, where he finds that the, um, the m- the production of these Acheulean tools is separated spatially about the place. So, the, the first step is bashing loose a big piece of rock, and that's done here, and then 10 meters over there, somebody's doing the initial chipping on it, and 10 meters over there, somebody's sharpening up the final touches. Now, if you were making it by yourself, why would you systematically walk around the site as you made it?

    2. JRJoe Rogan45:35

       Mm-hmm.

    3. WHWilliam von Hippel45:36

       You almost assuredly wouldn't.

    4. JRJoe Rogan45:37

       Right.

    5. WHWilliam von Hippel45:37

       But if you've got division of labor, you're the big strong guy, you do the first thing, then you hand it to me and I do the finer sharpening, it makes sense that it would be spatially distributed about the site.

    6. JRJoe Rogan45:47

       Hmm.

    7. WHWilliam von Hippel45:47

       So, there's that evidence for division of labor. There's the evidence that they're bringing down some pretty fast animals like horses and potentially even bringing down elephants, which in those days were like twice the size of an elephant. And then, uh-

    8. JRJoe Rogan45:59

       Were they using spears at that point?

    9. WHWilliam von Hippel46:00

       We don't know because they didn't survive, right?

    10. JRJoe Rogan46:02

        Right. Right.

    11. WHWilliam von Hippel46:02

        And nothing wood is still around. There's no sign of hafting anything. So, if it was spears, it would've been a wooden point.

    12. JRJoe Rogan46:07

        Mm-hmm.

    13. WHWilliam von Hippel46:08

        So, I think what they could do-

    14. JRJoe Rogan46:08

        Hafting meaning the end of it-

    15. WHWilliam von Hippel46:10

        Like-

    16. JRJoe Rogan46:10

        ... cut in half so you can stick a-

    17. WHWilliam von Hippel46:11

        No. No. Uh-

    18. JRJoe Rogan46:11

        ... spear tip into it.

    19. WHWilliam von Hippel46:12

        Yeah. Exactly.

    20. JRJoe Rogan46:13

        And then-

    21. WHWilliam von Hippel46:13

        Exactly. Strapping it on.

    22. JRJoe Rogan46:15

        ... tie it down.

    23. WHWilliam von Hippel46:15

        Or, or any of a variety of way put. Yeah.

    24. JRJoe Rogan46:17

        Yeah.

    25. WHWilliam von Hippel46:17

        And so, they ... There's no sign of that yet, but there's no reason why they couldn't have a sharpened spear. In fact, we know that, remember the, I mentioned the chimps in Senegal that live on the savanna. They're the only chimps on earth who do this. They'll bite the stick to sharpen it and poke, um, monkeys to ... When they're in the hollow of a tree and stab 'em.

    26. JRJoe Rogan46:34

        Did you see that recent discovery, and I mean, it's really recently. There was an article I read one or two days ago about orangutans, when they gave them wire, they used the wire to fashion it into fish hooks.

    27. WHWilliam von Hippel46:44

        No, I didn't.

    28. JRJoe Rogan46:45

        Yeah.

    29. WHWilliam von Hippel46:45

        That's totally cool.

    30. JRJoe Rogan46:46

        Yeah. They figured out what a f- how to make a fish hook, independently.
12. 49:49 – 1:04:50

    Theory of mind, teaching, and why humans ‘over-imitate’ (culture’s engine)

    1. WHWilliam von Hippel49:49

       What they're not clever enough to do ... So, chimps have partial theory of mind. And theory of mind is this idea that I know that the contents of your mind differ from the contents of mine, and all humans get there when they're little, around age four. And so the ... And you can see the penny drop because they just assume everybody knows the same things and everybody has the same pre- preferences. And, and that's why when they're really little, their stories can be hard to follow because they assume-

    2. JRJoe Rogan50:13

       Right.

    3. WHWilliam von Hippel50:13

       ... what's in your head is the same as theirs.

    4. JRJoe Rogan50:14

       Right.

    5. WHWilliam von Hippel50:15

       They assume you like the same things. And actually, it turns out that the ones who have siblings learn it earlier because like, "Oh, you like the red jelly beans? I like the green ones. Awesome. This is a beneficial deal for both of us."

    6. JRJoe Rogan50:25

       Ah.

    7. WHWilliam von Hippel50:25

       Right?

    8. JRJoe Rogan50:25

       Nice. Right.

    9. WHWilliam von Hippel50:26

       Anyway, chimps can get partial theory of mind, so I could see what you could s- I know what you could see at your angle if I'm a chimp.

    10. JRJoe Rogan50:32

        Mm-hmm.

    11. WHWilliam von Hippel50:33

        And I know that it might differ from what I could see.

    12. JRJoe Rogan50:35

        Right.

    13. WHWilliam von Hippel50:35

        But they can't get to the point of knowing that you could represent beliefs that aren't true-

    14. JRJoe Rogan50:40

        Mm-hmm.

    15. WHWilliam von Hippel50:40

        ... that you could have d- belie- et cetera. And-

    16. JRJoe Rogan50:41

        Or that maybe I don't like bananas, but he does like bananas.

    17. WHWilliam von Hippel50:44

        Yeah, they can't really get there. No.

    18. JRJoe Rogan50:45

        They don't get that.

    19. WHWilliam von Hippel50:46

        And so what the problem is, without theory of mind, how do you teach somebody?

    20. JRJoe Rogan50:50

        Hm.

    21. WHWilliam von Hippel50:50

        'Cause if I just assume you know what I know, then when you're doing a crappy job breaking the nut, I'm like, "What's wrong with Joe here?"

    22. JRJoe Rogan50:55

        Right.

    23. WHWilliam von Hippel50:56

        And so chimp mothers take years to, to teach their offspring to break these nuts open, 10 years on average, because first of all, they don't get a chance to do it very often. The nut's gotta be in season. Second of all, y- it's easy to break your fingers and that kinda slows you down. But third of all, they'll occasionally make some very specific corrections when the, when the offspring is doing it wrong, but they don't know what the problem is because they don't know what the kid doesn't know.

    24. JRJoe Rogan51:20

        Hm.

    25. WHWilliam von Hippel51:20

        And so when you don't know that, you can't teach, and that's why humans are stunningly effective teachers.

    26. JRJoe Rogan51:25

        That's fascinating. So chimps learn more just by observing?

    27. WHWilliam von Hippel51:30

        Yeah. And it- and what's amazing about the way chimps observe is that because we have theory of mind, we also do imitate differently. So there's this amazing experiment by Andy Whiting and his colleagues, and what they did is they created this treasure box. And so inside this treasure box, there's something that a chimp or a kid wants, like a little piece of food, and in the, in one condition, the box is totally opaque, so you can't see how it works, and they'll poke at the top of it, and then they'll poke in the middle, and it pops open, and then they give it to the chimp, close it up. Chimp does the exact same thing, poke, poke, poke, poke, pops open, give it to a kid, does the exact same thing. Now they do the, they do the... replicate that same experiment, but instead of having that- the box be opaque, it's translucent, and you can see well and truly that poking the top does nothing. The latch is actually right here, and so that initial poke was a waste of your time. This second one actually is the one that opened the box up. When, when chimps watch that, they skip the first one and boom, they just open the box. Kids, despite being smarter than a chimp, poke it at the top first and then they poke it in the bottom.

    28. JRJoe Rogan52:30

        Hm.

    29. WHWilliam von Hippel52:30

        And we call this over-imitation. They're imitating clearly irrelevant actions.

    30. JRJoe Rogan52:35

        Hm.

Episode duration: 3:00:24