#923 - Matt Ridley - Why Evolution Favours Beauty Over Survival

32:26There's no point in being brightly coloured and a lot of the display involves making clicking noises and maybe it's an auditory lec rather than visual leg, but other birds make noises on the leg too. So I kind of like my idea best that this is a species that's only just begun to leg. There's another bird called a buffbreasted sandpiper which sort of legs but sort of doesn't and I I'd like to watch that species for a thousand years and see what happens. What's the leg paradox? The leg paradox is that the black gross, which leg. Live next door to the red gross, which don't. They pair up, so one male, one female, and they both bring out the kids.

33:11Therefore, because the one male gets to mate with 10 to 20 females in the black gross, but the other 19 or 9 or 19 males on his leg don't get to mate at all that year, the bird will have less genetic diversity in its population than the red grass. It will be more genetically monotonous, it will be more in bread, not to the stage where it's a sort of health problem because the males usually only get one year at the top and the females disperse and so you know the species is fine in that sense. But it must be the case that there is less genetic diversity in a lacking species like the black grows than a monogamous species like the red grows.

34:08In which case there's less point in being choosy because the genes are going to be more similar. I mean when you go on to a leg you're bound to be looking at some half brothers because they tend to recruit to a leg near where they were born and if they were born in the same year then the chances are they had the same father even though they might have had different mothers. So if they're half brothers and they look the same and by the way they do look very similar to us then what's the point of being so choosy? The species that are most choosy about you know making sure you get the very very best male and not settling for second best which the Red Gras do all the time.

34:49They say, look, I just want to blow because I'm going to look after the kids. I don't care what he looks like. I'm anthropomorphizing, but you get the point. The species that are most choosy have least reason to be choosy. That is the lec paradox. I think the Fisher theory shows you a way out of it. It doesn't matter how little variation there is. You've still got to follow the fashion. But it's not really. I mean, you know, I'm struggling with it too. So it is a paradox and it's an intriguing one. This episode is brought to you by Woop. I've won Woop for over five years now. Since way before they were a partner on the show and it's the only wearable I've ever stuck with because it is the best.

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36:09So you can buy it for free, try it for free if you don't like it after 29 days. I'll just give you my money back. You can get the brand new Woop 4 .0 and that 30 day free trial by going to the link in the description below or heading to join .woop .com slash modern wisdom. That's join .woop .com slash modern wisdom. Right. So birds that have these speed dating, which is kind of bird speed dating is what sort of like the the the legging is in a way. Yeah, but speed dating where they all end up mating with the same male remember. Yeah, yeah. Okay. Good. No, it doesn't happen to you and me. Nonmenogamous speed dating, uh, birds, um, in those situations, you have a lot of the, uh, reproductive rewards are crewing to a few at the top.

36:57Yeah. You also have to assume that that would mean the more sexually selective, uh, the women are being the more that they're skewing toward that single male or small number of males at the top, there's going to be less of a chance of survival for that next generation that comes along, just due to some of the inevitable reduced genetic diversity. So you think, okay, these two things kind of do come into conflict a little bit with each other. The hotness and the fitness can actually start to, it feels like they can fight against each other. Yes. Well, the conspicuous prumids for a start is a threat to survival.

37:40the dancing and fighting that you do for months on end is a threat to your survival. So yeah, males are putting themselves at risk to present themselves. But one way of looking at it is that the black grass and the red grass, the males are putting in an awful lot of effort in both species. but the the red grows, the effort is going into escorting the female, defending the territory, escorting the chicks, helping the chicks, sheltering the chicks, keeping them being vigilant over the family and things like that. Whereas the black grows, the effort is going into endless displays, fights, competitive dances and so on.

38:29So you end up deciding which way to push your effort and when you push all your male effort into display, you are wasting it as far as the lineage is concerned, as far as the chicks are concerned, in the sense that you know, so if I go out in June in the Pennines. I can find a pair of redgroves in which the male is standing up looking around and the female is down in the heather with the chicks and and he's got his eyes out and if he sees a hawk coming he gives an alarm call and they all hide. He's very valuable in that sense. If I find a blackgrass with chicks there's no sign of the male. He's miles away.

39:15He's had his two seconds of fun two months ago or whatever. the female is entirely on her own and having a one parent looking after the offspring as opposed to two is bound to be a disadvantage. And sure enough, Blackgrass seemed to have lower chicks survival through that period of where chicks are small and indeed they have smaller broods actually. So the species as a whole is not going to do as well. And that's a rather intriguing thought, I think, that sometimes these sexual selection arms races end up making a species more likely to go extinct. That's fascinating. So, sexual selection could actually be a maladaptive force, sort of, that pushes species toward an unsustainable extreme.

40:01I mean, this idea has been around for a long time, and there was a sort of cartoonish version of it that was invoked for a while. Do you remember the ancient Irish elk? This species that went extinct at the end of the Ice Age, which was an enormous deer, bigger than a moose, and with huge antlers, much bigger than a moose's atlas, but similar in shape to a moose's atlas. And how on earth these poor deer managed to carry these vast antlers around. is sort of a bit of a mystery. And what were they for? Were they for fighting or were they for displaying? And actually there's some quite good evidence that they might have been more about display than fighting based on how could they would have been as weapons if you like.

40:55But the question of why that species went extinct used to be dominated by the theory that the antlers got too big. and the dear cotton fit between the tits, between the trees, when you're in my ancestor was running after them with a spear, and so they caught them. Now, nobody thinks that's why it went extinct. It was a large animal. Our ancestors were very good at wiping out large animals, which were slow breeding, and easy to find. and they wiped out mammoths and woolly rhinocerosies and stepped bison and things as well. So at the end of the I say it was doomed because it got predated by human beings, not because or because climate changed or something, not because they were, their antlers were too big.

41:43And besides, if you look in some of the best bogs in Ireland that have lots of these animals in them where they got stuck in the mud, there was higher mortality among young than old deer as you'd expect in any species. So, to that, you know, you can take these arguments about section selection being a handicap a little too far if you're trying to use them to explain the extinction of a species, but maybe it does play some role. How extreme can these traits become then? Well, if you... there's a little bird called the Club Wing Manakin, which has a display in which it makes a sort of resonant twanging noise with its wings, which carries a long way through the Ecuadorian Cloud Forest where it lives.

42:43And in order to make this noise. The bird has had to redesign not just the feathers of its wings, which are contorted in a sort of strange way, but the wingbones themselves. Wingbones are generally the same in all birds. Obviously there's a scale difference, big birds and small birds, but the shape of a wing but bone is generally pretty well defined as being the best strength to weight ratio and things like that. Not in this species, it's got a sort of weird heavy club shaped wingbone in its body, I mean in its wing, which is there purely to enable it to make a twanging noise in the spring time or the breeding system.

43:28They don't have spring in the equator. And Richard Prum was written about this in his book The Evolution of Beauty. And it's quite It's quite a good example of just the lengths. I mean, this must make it harder to fly for a start. The lengths to which actual selection can go. A peacock's tail. A, the, the, the, the, there are, there's a bird called the bull was a fuzzent which lives in Borneo, where the male when he displays disappears into an enormous sort of white disc which actually comes from his tail and his head is then hidden by fleshy inflated blue tubes that stretch before and after the head.

44:23So he looks like a sort of plate with a blue knife on it. That's not a very good description, but do you see would I mean, and you get to think poor creature, you know, what have the females done to this species to make it, to submit it to these old deals. But that gets to another point, which I'm intrigued by, which is that sexual selection can be possibly a more creative force, the natural selection, because instead of just saying in a utilitarian way, I just want to enable you to survive. It says, let's try something really wacky and see what we end up with. Richard Prum has this theory. He's the guy who worked out what color the feathers were on dinosaurs, by the way.

45:11And he has this theory that feathers were invented for display before they were ever used for flight. And that we wouldn't have had flight if we hadn't heard sexual display. Wow. That is cool. Yeah, I suppose if you're just rolling the dice in so many ways, it's like, hate, they might be attracted to this trade on. Here's a new outfit, here's a new fashion, have a crack. Exactly. Yeah. And I haven't mentioned the power birds, but I've got to get them in at some point. Australia and New Zealand, sorry, Australia and New Guinea where power birds live, these are birds that have basically invented art.

45:48They build complicated structures, not to nest in, but to seduce females in. It's the male to build them. And they decorate them with colorful objects, arranged in ways to enhance perspective and ways to look decorative and sorted by colour and all sorts of things. And I watched a great Bauer bird at his Bauer trying to seduce female with a red chili pepper which he was displaying to her on the edge of a cemetery in Queensland in Australia. But his main art installation was a huge patch of gray and white objects which snails, cells and bones and things like that but also bits of plastic and bottled tops and bits of broken glass, etc.

46:44because we were in the edge of a town. And this art installation included not only a plastic hand grenade, but a tiara, a toy tiara. I think it was a toy. Maybe it was a real diamond tiara. What about seemingly tiny traits, very sort of minuscule things that for us to look at, we wouldn't realize that it was actually a different, but that is something that's actually selected for as well? Yes. I mean, some of the song things are very, very obscure. A lot of sea birds, things like puffins, the male and female look identical. You really can't tell the difference between in the, they cam, but we can't.

47:44And they're both brightly colored. So there's a bird called a Crested Orchlit, which is a cousin of the Puffin, which lives in the Pacific Ocean. And there was a very neat experiment done on that in the 1990s, where they said they grow just a tiny little black sort of forward pointing crest on the top of the head and their beak gets much redder in the breeding season. So they took some birds, caught some birds and they linked them the top knot on the head or shortened it and then measured how long it took for that bird to acquire a mate and by lengthening the top knot you shorten the time that the bird takes to acquire a mate.

48:34the bird is more attractive and that was true for both sexes. So that's rather intriguing, that proved what we had suspected for a long time, that you can get mutual sexual selection, you can get choosing this in both sexes in some species for the same criterion. And then there's a bird in New Zealand called the Paradise Shelduck where the male and female are both smart but they look very different. The male has a black head and a grey patterned body and white wings. The female has an orange body and a white head that both striking birds, but they look quite different. Now clearly, you know, the females are saying, I want the male with the blackest head.

49:16And the males are saying, I want the female with the whiteest head. Well, does that ring a bell? Do human beings have mutual section selection? Yes, we're both very choosy when we pick long -term partners, but we don't have the same criteria, do we? You know, male beauty and female beauty are different things, both on the outside of the body and possibly on the inside of the brain. In other news, you've probably heard me talk about element before and that's because, frankly, I'm dependent on it. For the last three years, I've started my morning every single day, the same way with element in a cold glass of water.

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51:00Yeah, my book isn't about one ugly African ape, but inevitably, you know, one feels obliged to put a chapter in at the end. Let me start about this. And I'm absolutely be sure that sex with sex is going on in our species. I'm also pretty sure it's mutual and not not like the black grass in which you know it's female selectivity that's driving male appearance. I think in our both sexes are very selective where a monogamous species at least socially monogamous that doesn't mean we're necessarily faithful and we can be much less select, much less choosy when it comes to short -term sexual encounters, but for long -term pampere bonds, both sexes are pretty damn choosy about who they settle down with.

51:49That, after all, is the plot of every romantic comedy ever made. So what's going on in human beings? What are we selecting for? Well, clearly there are sexually selected features of bodies like breasts or beards or something that maybe involved in beauty. But I think it's more interesting to look at the inside of the head. Because the human brain did something very odd. It exploded in size over a relatively short period of about a million, two million years. Maybe three, I don't know, but not a very long period. It accelerated. The increase in brain size was very steady until around homo erectus.

52:34It suddenly takes off. And actually it's got slightly smaller gain in the last 50 ,000 years. We think it reached its maximum size about 50 ,000 years ago on average. And that might be something to do with agriculture enabling us to live on more meager diets or something like that. But it was very costly. I mean, the human brain is a huge user of energy. It takes a lot of to build it, takes a lot of energy to run it. Why? What's the purpose of growing such a brick brain? No other species needed it to survive on the savannah. And if you say, right, well, it helped us get through the ice age on the savannah when the climate was very variable.

53:22Well, plenty of other species managed to survive on the savannah, you know, buffaloes and gazelles and baboons and chimpanzees in similar habitats and so on. They didn't need 1200 CC brains. So maybe it wasn't all about survival, maybe it was about something else. Now there's two other possibilities. One is that it was a social thing that we needed big brains to understand the groups of people. or we were living in, we lived in big groups, we were plotting and scheming and deceiving each other. So we needed big brains to figure out what other people were up to and that kind of thing. And that's a very popular thing called the social brain hypothesis.

54:04And that's obviously to some extent true as well. But there's a third possibility, which almost never gets discussed, but which was laid out in a very good book by Jeffrey Miller 25 years ago called The Mating Mind, in which he says, actually, this looks awfully like a sectionally selected feature. It's a mental peacock's tail. The sudden takeoff, the fact that it didn't happen to other species, and the fact that the things we use it for are not just solving practical problems or understanding how to get on with each other in society. We also use it very conspicuously for things like wit and humour, music and song, verbal dexterity, poetry, all these kinds of things, toolmaking as well, practical things as well, some of which looks awfully like showing off to the members of the opposite sex.

55:07So maybe it's not at all difficult to see that people with great minds are attractive to members of the opposite sex in human beings. People with the verbal dexterity of George Clooney or the singing ability of Mick Jagger, these guys don't do badly in the attractiveness stakes. I've chosen male examples, but I genuinely want to keep stressing that I think in our species it's going both ways. Humor is a very good example. If you ask people at Helen Fisher did this, how important is humour to you in choosing a sexual partner? It scores very highly. And, you know, the personal columns, where people advertise for, well, I guess they don't do a name, but they do it online.

56:07But, you know, good sense of humor. GS -O -H is a very important part of it. And what's the point of who humor otherwise? You know, and watch what people do with humor. They show off with it. You know, they're not doing it to find out information from other people. they're doing it to impress other people. And that looks awfully like sexual display.

56:33So Miller says, and I think he's right, that this isn't a slam dunk, this isn't a proven idea, but to spend a whole of the 20th century thinking about Freud and Marx and Piaget and all the other theories of mind, behaviorism and all these things, without taking into account that the organ we're doing all this behavior with was probably subject to sexual selection and was probably being used to seduce as well as to survive. To do all that without taking that into account is a mistake. We might have left an enormous hole within a lot of our social science within psychology and sociology and economics and all these other disciplines, the whole being sex.

57:25And we need to put it back in there. It's mating all the way down. It was always mating. It's turtles all the way down. It is. So, you know, one of the things that you've mentioned there is this, I guess, bidirectional sexual selection that traits happen both not just male to female, but female melt a male as well. What determines whether it is unidirectional or bi -directional? What does that say about the environment and the child re -ring and the expectations of that particular species? How does that all fit together? Yes. The person who solved that problem was a brilliant evolutionary psychologist called Robert Trivers, who said something that's blinding the obvious, but none of us had thought of it before.

58:15And he said it in the early 70s. He said, the species where the sex that invests most in rearing the offspring will be competed for by the sex that invests least. So it's called parental investment.

58:38But it's a vicious circle because, as I say, the Red Grouse, they both invest a lot in looking after the kids. The Black Grouse, they don't, the female does it all. So the Black Grouse, you get a huge amount of male -male competition to try to mate with females and a lot of sexual selection less in the Red Grouse. But which came first, the chicken or the egg, you know, was that did the parental investment come first or the sexual selection come first? And the sort of exception that proves the rule here is those species of birds where it's reversed, where the brightly colored forward and aggressive females compete for dull coloured males because the males sit on the eggs.

59:32I studied one of these species, it's called the Gray Fala rope, it lives in the Arctic. Fala ropes, jacannas, dartraels, there's a number of species that do this. It's not very common but it's not all that rare either. And the female is much more conspicuous, much more boldly colored, much more spent, much more time displaying and much more inclined to fight with other females. So that kind of proves Trivers' parental investment theory right. Now in human beings you can say that women do more of the work and of course they do, they do gestation and lactation which men can't contribute to at all, but compared with gorillas or chimpanzees, males do contribute an awful lot more parenting than most other great And we are, we have less sexual dimorphism than most other great apes.

1:00:45I mean, you know, male gorilla weighs twice as much, if not more. Three times as much as a female gorilla. And he has a R -E of six or seven females. In chimpanzees, they have a multi -male system where each female mates with lots of males, partly to frustrate the tendency of males to commit infanticide, which they do in a lot of mammals to bring females back into fertility, probably in human beings too. Look at the number of step children that get killed compared with biological children. The murder rate is much higher. The Cinderella effect, as it's known. The Cinderella effect, exactly. So, you know, it's unfortunate that there's only four great apes around the tanks, chimpanzees, gorillas and us, plus the gibbons are similar species, because if there were 30 or 40 species of apes, then we could really do some good comparative analysis and see how we ended up with the mating system that we did.

1:01:56But I would argue that the need for fathers to be involved in provisioning and protecting offspring as well as mothers has been a feature of how to gather a life for a very long time. And it has made us into a species in which females are going to be pretty choosy about males as well as males being pretty choosy about females. Are there any parallels between bird mating behaviors or whatever and human romantic displays or social structures? Well, it's hard not to watch some of these bird displays and not draw parallels with nightclubs and other things. You know, there's a strutting that both species do, I suppose.

1:03:02but I think that's mostly anthropomorphism. We, you know, we human beings, well, I think song is actually the most intriguing one because there's no other mammal that is as interested in singing as we are with the possible exception of Gibbons, maybe Halem Monkeys. But we, song and language, are very unique and remarkable human features and they feature heavily in seduction and display. That's true of many birds as well. And the complexity of song in birds is truly extraordinary. The number of different phrases and different motifs. Oh, sorry, I've left out whales. I've not really seen as much as we do, so there are another example.

1:04:09But I think, you And we, when you, when you try and teach a chimpanzee to speak, it's really tough. And you can get up to a few hundred words. You can't get grandma, you can't get syntax really to speak of. Same for a gorilla. When you try and teach a parrot to speak, and this has been done, there was a famous African in paracord Alex, who was an enormous vocabulary, and really seemed to understand grammar in a way that any other, most other animals can't, the word order or whatever matters in terms of what it means. In that sense, there are similarities to us and birds. Okay, another similarity question, I guess, do birds and humans have a innate appreciation for beauty?

1:05:14Is the drive for aesthetic pleasure some evolutionary force? There's a rather good quote from Darwin on this, which I'm rather fond of, which is, birds appear to be the most aesthetic of all animals, accepting, of course, man, and they have nearly the same taste for the beautiful as we have. And, you know, he's really flirting with a dangerous idea there that, you know, there's something uncannily similar about us and birds here because there's no reason why. You know, it's convergent evolution if we and birds have this similar taste for the beautiful. And one of the things that I've been thinking about is it's unlikely to have been inherited from a common ancestor.

1:06:11There's taste for the beautiful because our common ancestor with birds we now know lived about 400 million years ago. That's an awfully long time ago. And we know what that common ancestor looked like roughly. It was a lumbering reptile that lived in a swamp. It gave rise to both the dinosaurs, which gave rise to the birds, and to the so -called mammal -like reptiles, which gave rise to the mammals. So we're not close cousins, descended from a creature that had a sense of the beautiful, probably, maybe we are, but it doesn't seem likely. It seems more likely that we have ended up with an appreciation of colour and tune and song and melody and fashion and all these kind of things.

1:07:01And so have quite a lot of bird species. And it just so happens that those have ended up with similar outcomes. Now, why might that be? Well, notice that on the whole section selection goes for pure colours, not browns and grays. So it goes for limited number of wavelengths, limited number of frequencies, pure hues. If you've got every hue, you can think of, then you end up looking brown. And it's the same with song. If you just want to make a noise, a click or a roar or something, it's got every sort of frequency in it. But if you go for just specific frequencies, you get a whistle or a tone or a tune.

1:07:58And that's of course much harder to do. I mean, you can make a boring noise by dropping a rock or you can paint something brown just by mixing lots of materials together, but to actually create something that has a pure color or a pure sound is much more improbable, much more unlikely, much more conspicuous, much rarer, and that's why we find it. That's why we use it in our sexual displays, and that's why birds use it in their sexual displays. And so there's a sort of almost a thermodynamic idea at the root of this. But as you can see, I'm beginning to wave my hands a bit, and I haven't thought this one through properly.

1:08:48I like it. I mean, definitely the refined nature of it not being everything suggests that you're purposefully doing this one thing. If you're brown, this, you didn't mean to be brown, you just are brown. But if you're such a pure color, if you're such a pure note, or tone, or sound, or whatever, that suggests that there's been some thought put into it, some pressure selected for it. Yes, there's a sort of watchmaker aspect to it. What do you think, so taking a broader picture here, lots of past failures in evolutionary theory, trying to work out why things were the way that they were. What do you think we should learn about biases in interpreting our nature, what we should consider, where things come from, given the repeat history of us putting off both of our feet in our mouths and getting stuff wrong all the time?

1:09:46Well, for me, the Institute of Science always teaches the importance of humility, and overconfident rejection of maverick ideas is the constant theme of all science. But that doesn't mean that every maverick who comes along waving a new theory is Galileo. Quite a lot of the time he's not, or she's not. And how, for me, that's, that's the big puzzle of my life is how do I know when to listen to a maverick and when to tell them to get lost? Because you know there are many many scientific debates where you just want to say oh for god's sake get real that idea can't be right and 95 % of the time your right to have that attitude but five percent of the time you're being like Catholics and being dogmatic and telling a perfectly sensible chap to get lost when you shouldn't and this was true of Darwin generally is that he was a maverick and a heretic and and he had to work really hard to get taken seriously and evolution was rejected and still is by many people and it's true of his sexual selection idea where he did, he was rejected as a nut case in his lifetime and for quite a long time afterwards.

1:11:18And wrongly so.

1:11:22But you know, since then lots of people have put forward fresh ideas about why birds are colourful, for example, to go back to this. There was a theory in the 1980s that it was all about warning predators that you were in good health and therefore there was no point in chasing you. Well, I don't really see why a kingfisher needs to do that more than a sparrow, but you know, maybe there's an idea there. And in general, I'm more frustrated by science being too dogmatic than being too open to new ideas. Yes, if you're too open to new ideas, if you open your mind too much, your brain falls out for someone once put it.

1:12:14But I would like generally to teach the lesson that we need to be more tolerant of disagreement, of heresy, of mavericks and give them at least the privilege of testing their ideas. And that said, you often get told by people, I've got this new theory and the line I always come back with was, how are you going to test it? And that often shuts people up. So it's lazy to come up with an idea. It takes work to test it. Awesome. Matt Ridley, ladies and gentlemen, Matt, massive fan of your work. I think this is really, really interesting. I didn't realize I was going to become such a garage -orn -a -thologist for the afternoon.

1:13:07Where should people go? Do you want to keep up to date with your work and what you've got coming out? Well, I have a website which I mostly keep up to date. It's called matridley .co .uk. I'm just about to get on the sub stack, I think, too I can turn my stuff out there. But I'm on Twitter, I'm not very active on Facebook and LinkedIn, but I try and be. And I write books and journalism as well. And the book is called, I should say, a bird, sex and beauty, the strain, the, the, the, what's the sub -tile? The implications of Charles Darwin's strangeest idea. Yeah, Matt, I appreciate you. Thank you.

1:13:59Thank you so much for having me on and loving me to rabid on at such length.