[speaker001:] without picking serious note of Freud, it's a bit like... you know discussing space high on gravitational without mentioning Einstein, I mean, you know th that's wh what people seem to do, and it strikes me as ridiculous. Er, but, you know, Freud discovered so much about consciousness and unconsciousness that erm, you ignore it, strikes me as just silly. Well, I think a lot of what happens in the academic world is, and my guess is the fundamental reason they get away with it, is that young people won't buy much, spending their own money on it, and I think if they were, you couldn't serve up a lot of the crap that passes for higher education today. Consumers would want something better.
[speaker002:] Most people end up neither of them are prepared
[speaker001:] No, well, that's true. But erm, and it's a big book that book, isn't it
[speaker002:] Oh, yes [LAUGHTER]
[speaker001:] A hundred and fifty thousand words, at least. You'll notice that I gave that one a miss, because I had erm, so much more pressing things to do. But, erm... perhaps I'll get round to it. Anyway, he's coming to the conference, so I dare say I'll sit and hear what he has to say.
[speaker002:] So wh what kind of writing are you doing anyway?
[speaker001:] Well, I'm writing a popular science book, at present.
[speaker002:] Yeah.
[speaker001:] Called Psycho-Darwin, cos you know there's a big boom in popular science publishing and erm, I got a New York agent called who's very good at selling people books, and he's sold, he's sold mine. And so now, I've just got to write it. That's coming on quite nice. And I'm trying to present the kind of things I do in this course and my other course. Erm, in oth in a way, you know that any erm interested reader could understand.
[speaker002:] Mm.
[speaker001:] And for me, it represents an opportunity to complete the kind of Freud-Darwin synthesis I've been working on really, for the last ten years, and it kind of represents the completion of the synthesis, as it were now completely merged... in my mind into a single, the single kind of entity that I, I know call psychoanalytic. So that's basically what the book is about. It's primarily put over as a kind of erm, power line to the future.
[speaker002:] Well I mean, would you, would you have said to begin with, or
[speaker001:] Not, yes, it's based on what erm, on the kind of stuff we've done in this course. The idea that, that human beings are a species whose social interactions are very critical, as we know social interactions are also very important to reproductive success, and so I bring in inside this analytic cooperation the idea about deception and the evolution of the unconscious, that press deceivers don't know that, deceiving. Did you do that paper?
[speaker002:] did that paper
[speaker001:] You did, you did. Fine. Erm, well, what you did, when you talked about that, and then erm, linked it up with Freudian insights into the unconscious.
[speaker002:] Ye yes, so... so you aren't happy with to begin with.
[speaker001:] No not, problem neurological.
[speaker002:] so you're saying... naturally arises because of its complexity of how it interacts?
[speaker001:] Yeah, I'm talking about how it arises from the evolution point of view, as an not, I don't go in at all to the whole neurological question, or how the brain is produced consciously. I honestly don't think we know enough, well, anyway I'm not qualified, erm. Well, even if I were qualified, I would be very, very sceptical, because I think we just don't know enough about that yet. About having brain cells. But then it does go into that side, because it goes into...
[speaker002:] Yeah, that's, that's well.
[speaker001:] I mean, what does he call himself, a cognitist scientist or some other thing?
[speaker002:] I think so, yes
[speaker001:] That's his area, and cognitist science is supposed philosophy, psychology and...
[speaker002:] Computer science
[speaker001:] and computer science... I mean, that's where the answers all come, I'm quite sure, I'm just sceptical, that we know how much about it. And what about the role of language, does he, cos my theory an and, and Freud's for that matter, original, but erm, does he give a role of importance to language?
[speaker002:] At the end, I gathered
[speaker001:] Cos my thing is, that language is critical. I can't see how you could be conscious, without it matters, but it's interesting you know the hearing tests we were talking about. I mean, you were I know you said something about that in the past. That really is trying to, erm, discover whether the person on the other terminal is human by means of language, and really, you can't think of any other way of doing it.... Well, it's five past according to my watch. And I'll do, I don't know about the other they seem to be all over the place today. Right, let me find my evolution... folder, which is here. Okay, and here. Bits, bits of it are here. Erm, er who's performing today? You are, and what are you telling us about? Right. So you are.
[speaker002:] , can I just ask
[speaker001:] Mm, today.
[speaker002:] I won't be able to to your lectures, cos
[speaker001:] Oh, how irritating. Erm, well, I'm sorry about that. That kind of thing shouldn't happen. Could you change your class if it were really...
[speaker002:] Yeah, the other one's at the printer form now, by the way.
[speaker001:] Oh, I see, I see. That's the summary I handed out the last week, you wouldn't have got...
[speaker002:] Thank you.
[speaker001:] and that's the summary of today's lecture, you would get next week.
[speaker002:] Thank you.
[speaker001:] Well, I'm sorry about that, I mean that, that's really very naughty of them. Wh what, what er, answers that? Mm, I suppose they have to do it because of the computing erm, departments, has some equipment they want. Oh, dear, I'm sorry about this. Anyway, it's only for a few weeks, you said. Okay, well, er, complex. Tell us all about it. Well done, excellent, erm, as you can see, in some ways quite a complex er, issue, and it's one of those things really, I think to fully understand this, you got to sit down with a pencil and paper and work it through yourself. I'll, I'll go through it, erm, fairly carefully in the lecture. Erm, let's start with the simpler issues though, that mentioned at the beginning. Erm, and that is the whole question of conflict about parental investment in general, and er, she put it very well and, and, and, and very clearly, and I'm sure she understood it, but let's make sure that everyone else does. Why, should there be conflict over parental investment, because after all, children are the link product of success of their parents, so shortly child and parent have got exactly the same self interest haven't they?... Yes, and that's a good erm, starting point. The, the point as says, one has to bear in mind is that, okay, in general fostering are the successful parents, but the parents probably have more than one offspring. So, erm, how many people here have got brothers and sisters? you do, well everyone's got brothers and sisters. Well, erm, you've all heard of sibling rivalry and sibling conflict. Thank you. Erm, does anybody not believe in sibling rivalry and sibling conflict? It is something that everybody is... with you, yeah, Right, well now how does that relate to what just said. [cough] Wh what's the... what's our theoretical insight into it, given what we've done about natural selection parental investment. How could we explain that? That's what our peer would lead us to expect. It is true, is that right,. What do you think?
[speaker002:] Erm, certainly when you're, you're very young, I mean that when you're driving for attention.
[speaker001:] Mm. Could you give us an example, or...
[speaker002:] Erm
[speaker001:] You got an example. You got attention.
[speaker002:] Attention. Yes,
[speaker001:] Yeah.
[speaker002:] yes, just for instance, my brother pulling my hair in the back of the car and annoying me. You know really screaming and getting raged [cough] really resentful and then, you know, back knows ultimately you're wanting parents to side with us.
[speaker001:] Yes.
[speaker002:] So it's sort of, you know, we want to be favoured because we want all the reward, we want to be given a sweet, we want
[speaker001:] That's the basic idea, isn't it? That's an excellent is your brother older than you?
[speaker002:] No, younger.
[speaker001:] Oh, younger, I see. pulling big sister's hair. [LAUGHTER]
[speaker002:] Yeah I still got the blame for it
[speaker001:] Oh, yes, life is never just. Erm, does everybody else go along with that? Is that everyone else's experience? would y does this happen in Japan? Are, er, little brothers just as naughty?
[speaker002:] [LAUGHTER] Erm, yeah. My brother is much younger than I. I don't know.
[speaker001:] So you're expected to give your sweets to your older brother, dear oh dear. You were younger, was he younger or older?
[speaker002:] Yeah. I, I older.
[speaker001:] So he was younger?
[speaker002:] Yeah.
[speaker001:] I see. So, even though he was younger, erm, and did you resent that? Were you angry about that? How did you feel about... Sad, sad, you were sad
[speaker002:] Mm
[speaker001:] Erm... the... why should a parent, looking at this pretty critically why should a parent want an older child, like to give up something to a younger one? Is there any biological action can you see any? Right. Right the rationale is that the degree of parental investment and its effect on the offspring vary with the offspring's age, and as says, one of the fundamental erm, principles of this is that the, by and large the younger the offspring the more valuable any unit of parental is to it, and the more efficacious it is, and the most obvious example of that would be food. Obviously, if you're a very tiny newborn baby, the amount of food you need to er, put on extra pound weight, is, is not going to be the same as if you are a much larger child, and you want to put on proportionately the same amount of X pounds, whatever it would be, it would be same the same proportion of your weight. Er, it could be one pound possibly with a child. You'd have to eat a lot more. So the idea is that erm, a parent may have an interest in diverting the sources from older offspring to younger ones, because younger ones might benefit more from the same unit of resource. Because they're so much smaller, and perhaps this is what was happening in your case sounds very unfair, to me, but er, but, but, but there we are. Perhaps it did. The erm... perhaps the best example of this to bear in mind, and again that mentioned er, erm and explained very clearly, but I think we to mind, is weaning complex. Now, did everybody understand that? do you understand about the weaning complex? Well, mentioned it. Perhaps we ought to lo well, what is weaning? Everybody knows what weaning is mm? What's weaning for? I'll explain, what weaning is. Ya, ya. It means erm, specifically, wean the breast, so that the child accepts solid food or that's what in general means erm, getting a child off baby food as it went on to adult food. Erm, okay. Why should there be a conflict about weaning? Again, surely both child and mother have the same approach on it, erm, where does the conflict come in over weaning?
[speaker002:] It shows more child, whereas
[speaker001:] That's absolutely right, well done. Yeah, the, I don't think erm, mentioned this in her paper, but er it's a, it's a point worth, worth mentioning in passing because it er, it er, underlines what er, you've just said. But in, in mammals, as a whole, I think there are few exceptions, and certainly including human beings. The er, sucking of the offspring inhibits the mother's cycles and it is the sucking, it's not the actual of sucking, it's the neurological stimulation of part of the mother's nipples. This inhibits her sexual cycles for varying periods of time depending on the species it's about two years. Now, you can see that in the ma mammal where this happens, there could be a very clear contrary as says, between the mother's desire to start another offspring towards the end of the period of, of breast feeding, and the offspring's interest in having some more milk and postponing the birth of the sibling. So, we can expect conflict and, and did make this point, but we need to underline it, because it's very important. When we talk about paradoxical conflict, we can expect the conflict at the margins we, in other, if we made er, if we made er kind of diagram of the parents' self interest in providing parental investment and the offspring's self interest in demanding parental investment, we find that there are large areas of overlap. For example, erm, in the case of newborn, or young or a very young offspring, and a, maybe a mother has already put a tremendous investment into that offspring, as you've already seen. So, her self interest and the offspring's self interest are the same as father's intended. She has a self interest in giving her milk to, to er grow to a point where it can survive on its own. She's already invested so much that, and the offspring has got a self interest for getting as much as it can, so their self interest coincides. Where their self interest comes into conflict, is at the margin, and the margin can be in any dimension. One dimension might be in this time, as we have seen, the mother might reach a stage where, she, it's in her productive self interest to start another offspring, and she may want to wean the existing one, so she can do that. Switch resources, as it were. But the existing offspring may benefit more, may need a little bit of extra milk, so the existing offspring may try to erm, demand more milk, or at least milk for longer than the mother to supply. Right. That's right. The same thing will apply in the terms of quantity. The offspring will probably be selected to want a greater quantity of parental investment than the parent because again, a little bit extra for the offspring probably means more than what to its reproductive success, than it er would mean to the reproductive erm, success of, of the mother, as far as the offsprings are concerned. And the example that, that gave following which was a good one, is crying. Now, erm... why do you think, why do kids cry so much? And so in intensely? Cos half the adults don't do they, or if they do, it's normally taken as a sign of severe... erm, upset, isn't it? Erm, if erm, if one of them contradicted me in the class, I burst into tears, I think you'd think something was seriously wrong with me, wouldn't you? Whereas, if I was a kid, and you took my sweet away, and I'll contradict my you wouldn't do it, would you? You wouldn't be so concerned, why is that? Well, that's the way we rationalize it, don't we, but supposing we were Martians, you know, weren't used to it.
[speaker002:] it's all I want is attention
[speaker001:] Well, that's true, that's true as well of course. But the, the reason why that's true maybe, mightn't it, that if you look at it from the child's point of view, the crying is a, is a signal it's sending to its parent. Basically to say, er, look after me, or give me what I want, or er, do what I want you to do, or whatever it may be. In some counts, a signal of distress but is attempting to solicit something but is usually what we would classify in our abstract concept of parental investment. Now, if, if a child sends a distress call to a certain level of intensity, it may get a certain amount back, but it may have a sibling who sends the distress call a slightly higher level of intensity and might get some more back. So the idea is idea is that a kind of arms race will develop between the siblings to amplify the signal to get as much back as they can from, from the parent. So the result will be, that the young children will cry an awful lot over about very small things, because what they're doing is they're amplifying the signal to a maximum level. The parent on the other hand, will tend to get erm, a little bit, erm, a little bit sceptical about this. The parent will tend to recalibrate their response, as, as, as you have said, parents will come to expect children to make a lot of fuss about nothing, and consequently won't pay so much attention to a child's distress as they would to an adult's, because we regard it as natural, children to cry or make a fuss about the treatment we contribute, but the reason for that could be that we, we have as it were, readjusted our sensitivity to distress and we, we really have a double standard. We have a standard for children which assumes they can either send very strongly amplifies the distress, and therefore, we are not going to taken them terribly seriously, or at least they can actual reach much higher intensities before we do take them seriously, whereas for adults we have a different standard which, which assumes that even slight expressions of distress in adult could be serious. So so erm, basic idea about crying is this kind of arms race situation, which offspring have been selected to amplify the signal, because it promotes their reproductive success, to get every little bit of extra parental investment we can for themselves. Parents have been selected to become erm, relatively insensitive to signs of distress in the offspring, because erm, as where they cry wolf all the time, and as a result, erm, parents don't take crying as seriously in children as they do in adults. There are other examples of this, and one interesting experiment that we've just done with birds, was with the gape response in birds. You know that when birds are chicks in nest, they gape, their little mouths open wide, like this, and they, whenever the parents come back to the nest,wi with a worm or something, you see the little chicks, their little mouths wide open, they kind of reach out of the nest and, and, and try to to their feeding. Well, in this particular experiment, what the experimenters did was, when the parental birds left the nest, they stuffed the erm, the chicks as full with worms as they could possibly stuff it. their throats were completely erm, full of worms, and they couldn't get any more worms into those throats, so they knew these chicks were totally full, as full could be. When the parents came back, the erm, gaping behaviour was exactly the same. There was no difference between a chick that was totally full of worms and couldn't have handled any more worms, but still as it were, behaved as if it was on the point of starvation, and a chick that was really hungry, had in fact, observation shows that, what parents do when they come back with, with the food is, very often they, they probe the throats of the chicks with their beaks, to see which one's got much most room before they actually put the food in. So you often see on nature programmes, for example, when a bird comes back to a nest with several chicks in, you see the parental bird kind of poking its, its beak in the in the gaping beaks of all the chicks. Not because it's feeding everyone, if you look closely, what it's probably doing is checking how much food is in their gullets. It's got a worm, and it finds one that's relatively empty it sticks the worm into that one. So the parents are being discriminating, but the chicks are being very demanding as it were. have got totally banished, and, and they, they grow but the parents are being discriminating, because it pays the parent to discriminate and feed the ones who really need it, but pays the offspring to, to demand as much food as is possible. So everybody with me so far?
[speaker002:] weaklings, you know in erm, how intervals, affect the survival of offspring. So could you say this was in the modern society effect. You know to keep
[speaker001:] Oh, yes, you could, you certainly could, and as I said for long periods, parental an and offspring self interest will overlap. It's at the margin where they're probably wont. In other words, there will always be a tendency for, probably for the offspring to want the mother to go on breast- feeding for that little bit longer tha tha the mother may. So that th the weaning conflict will occur towards the end of the period of parental investment. An interesting example of this, I read about recently in the press. Last week's New Scientist, I think it was, or the one before, was a study of one particular type of bird with, I can't remember wh what kind of bird. It was kind of dark, and apparently what happened to this, towards the end of the period of parental investment, when the parents come back to feed the ducklings, they insist on the ducklings following them. They run away from the ducklings and the ducklings have to follow them, and chase them as it were, and the one that catches them, is the one they feed. And it looks as if this behaviour is all about encouraging the ducklings to erm, go off on their own, as it were an and to start to run off and look for food. So what the parents are doing is they're rewarding the duckling that runs the furthest and the fastest, to erm, they're trying to reinforce that behaviour, because what they're are trying to do, is get the ducklings away from the nest and start looking for, for food for themselves, presumably. So here here's a case where this conflict of interest leads the parents to actually kind of encourage their young to leave the nest and, and, and wander off. The supposition being that it's always easier for the offspring just to sit on the nest and wait for the parent. Erm,th that's easy, it doesn't expend any, any energy and er, from the offspring's point of view that's worth facing. But not necessarily from the parent. Okay. So is everybody with us so far, because this is when it starts to get difficult. Because now, let me try and confuse you on that. I hope I will, erm. Are you chilly? I'll go out, I'll go get the windows that shouldn't be open north. Perhaps the central heating's going down, one minute. If I can turn on. Erm, let me try and confuse you first, and then enlighten you later. Because you know it's a common trick in education. Erm, let, let me give you the confusing bit. Surely, surely human altruism shouldn't mean, that there shouldn't be sibling conflict, because human altruism shouldn't mean that since all siblings are equally related to their parents, given you that they're called siblings. There should be harmony, not conflict, shouldn't there?
[speaker002:] No. You've still got your own brother.
[speaker001:] Right. Can everybody see that? You see, you could say, surely there shouldn't be a weaning conflict, because an offspring should say to itself, okay, my mother wants to wean me, to have more offspring, but those offspring she's gonna have are my siblings, I'm very closely related to them. In fact, I'm as closely related to them as my mother is, if you think about it, because I share half my genes with my four siblings and my mother shares half her genes with my four siblings. Therefore, our degree of relatedness is the same. Therefore, my self interest in having siblings and my mother's self interest in having children are the same. But that argument is fallacious why? Oh, yes, I've only just said it. Right. This is the important point, you have to know it. That's the best way. But this is the way er puts it, and I think it is a very good way of, of, of putting it, as both and say, the point is, that every individual offspring is twice as closely related to itself, as it is to its, to its siblings. So it's quite true of course, that the, the individual offspring wo may be affected by inaltruism. In other words, erm,whateve the R is greater than C. Do you remember our, our formula for penaltriate benefit of an altruistic act exceeds the cost discounted by the degree of that's between a half normally. The offspring ought to be so put to that's perfectly true. However, the point you have to erm, recall, is that if it's a conflict between parental investment in a sibling and parental investment in myself, I am twice as closely related to myself as I am to my sibling. So when my parent is handing out the parental investment, I will be selected to want the parent to give the investment to my sibling if the benefit is twice as great as it would be to myself. But if it's less than twice as great, I'll want it for myself. Does everybody see that? Right, now comes the next step. How does the parent see it? We've described it from the offspring's point of view. How does the parent see it? Because the parent doesn't see it the same way. How does the parent see it?... you, you're a parent, you've got a unit of reproductive success.
[speaker002:] Erm, what you mean, if, if one reacts about it
[speaker001:] Mm.
[speaker002:] Bear in mind that see it but it's more likely to pass on energy units, because it's the stronger, you know. It's more likely to reproduce it in itself.
[speaker001:] Yes. Yes, it might, it might, but, but, but now you're getting a little bit, you're getting a bit too, too sophisticated now, we're going to come on to that later. Erm, we're looking at all other things being equal. Let's assume that all the offspring are the same, in quality. Even, let's even make them all the age. Let's say they're all the same in quality, they're all the same in age. There's still a difference as far as the parents are concerned. Can anybody see what it is? Well, alright, I mean. Let's deal with the first bit first. Why should they treat them all equally? Why, why does the parent regard its offspring equally? In what sense? Why? This is the important one. From the parents' point of view, it is equally related to all its offspring. Now this is, this is the counter-intuitive bit. Supposing I'm a parent. In fact,let let's do this in terms of a little diagram. Let's put this on the board. I'll do this in the lecture. But let's just do it. It's easier if you do it on the board, and you can see it. Let's, supposing that I am the parent. Okay. I'm the parent P. Here am I, parent P, okay. I have two offspring, A and B which are smaller, little er A and B offspring A and offspring B, and they are exactly equal in eve every point of view, size, quality and animal okay. Now, erm, supposing that er, I have ten units of parental investment, and I invest ten in A and ten in B because I'm equally related to both of them. Okay. Now, supposing that I want A to do something for B, like in 's case, A to give up a food item for B. Okay. Now as far as I'm concerned, if the benefit to B is greater, supposing for example, they're not the same age, sorry, I shouldn't have said that about being the same age. Er, supposing they're not the same age. But supposing I invested equal amounts of parental investment in both and supposing that if offspring A gives two units of parental investment to offspring B, the benefit to B's reproductive success will be three minutes, which it could be, if B was younger. Okay, A gives up two units of reproductive success, a food item to B. This benefits B by three units of reproductive success, whereas it would only benefit A by only two units of reproductive success. In arbitrary units, okay. Now, clearly, I will favour that, because now, B has a total of thirteen units of reproductive success and A has er, a total of eight units of reproductive success, because it's lost some. So totals here are thirteen and eight. Thirteen and eight is twenty one. In other words, the total reproductive success that my parental investment has produced is now greater than it was before I started. So, since I'm equally related to both, in other words, I have an equal number of genes in both offspring,th this, this transfer has promoted my overall reproductive success. Therefore, I as a parent will be selected to want that kind of thing to happen. Okay. You with me. Now, let's go back to what and say and look at it from offspring A's point of view. Offspring A looks at it differently, because offspring A says, my sibling B has only got half my genes, therefore I will make sacrifices for B, wherever B R and greater than C as we saw. Now, in this case, the, the sacrifice is er, two units of reproductive success, they benefit er B by adding er, one unit of, of reproductive success to it. So the cost to me is two, er the benefit to my sibling is one, and the degree of relatedness er, is a half. So the sum has to be one, times a half, is greater than two, which it clearly isn't, cos one times a half is a half, and that is less than two. In other words, I as the offspring are not gonna want to transfer those two units of reproductive success. So when my parent says to me, give those two units of parental investment that I just gave you, to, to offspring B I don't want to, because the benefit to offspring B, or rather the genes I share with offspring B, doesn't compensate sate me for the, for the sacrifice. I'm losing two units of reproductive success. My offspring is gaining one unit, that it wouldn't have had otherwise. Erm, and, that is, that is not a good deal as far as my shared genes are concerned. So the... Oh, sorry, three, yes. Okay. Yes, you're right, sorry. cos it two...
[speaker002:] three times half.
[speaker001:] Sorry, three times a half. So, it's three units that I'm giving my siblings. Right, three three. The total benefit is three units of reproductive success, three times a half again, is one and a half, it's not erm, it's not the of two. If you think about it, er, there are numbers that will, that will make it work. Larger numbers. If erm, what would it have to be? It would have to be at least, erm, what would it have to be, it would have to be at least the benefit, yes, the benefit would have to be at least four on the, on the B's side, in order for that to work. Anyway,the these erm, numbers don't matter, this is just an arbitrary example. The fundamental point that you have to grasp is... that parents want any transfers between their siblings that will result in a net gain for the, a, sorry, parents want any transfers between their offspring that result in a net gain for reproductive success. It doesn't really matter to the parent, which offspring has gained, as long as there is a net gain. All other things being equal. The offspring, however, don't take the same view. For them, all other things being equal, they will only be selected to make a sacrifice, where the benefit is twice the cost. If you work it out for other relatives, the discrepancy gets even bigger. As mentioned, if you work it out for maternal erm... for maternal cousins, for example the benefit turns out, has to be at least eight times. So the principle, the fundamental principle is that, conflict between parents and offspring, over a we over a... altruism, over self-sacrifice, or, selfishness, which is the other side of it. Because, this works just as well for selfishness, because, if you think of it, selfishness is negative altruism. It's the opposite altruism. Parents will always want twice as much altruism, or half as much selfishness as the offspring, our certainty to. That's the whole thing in a nutshell. In other words, the conflict between parents and offspring, over offspring behaviour is not rooted in culture and nature, as we often think it is. It's rooted in evolution. It's rooted in biology. fo for example, says, that he, about his first erm, experience, was as a field observer of baboons in er, Kenya or somewhere. And this is one of the first, on the first day, he was astonished to see, an older male baboon intervene in a fight between two younger ones and stop it. And this astonished him, because he'd seen this kind of thing at home. He'd seen human parents intervene in conflicts between pa er, between er offspring. You know, like, like er parents did, when her brother was pulling her hair, and she wanted to clout him. I daresay they intervened to stop the fight. [LAUGHTER] Well, what observed exactly the same thing with, with baboons, and said to himself, why are these animals doing this? There has to be a reason why, all the male baboons who have got no particular self interest in, well there's no obvious sign, in a fight between two youngsters, nevertheless he intervened to stop it, and he had realized that the reason, well he ultimately realized, development of parental investment, the reason they intervened to stop it, is that parents do not have the same self interest as their offspring do, when it comes to behaviour of offspring. There's a fundamental ineradicable conflict of interest, because the parents will want any gain to their offsprings net reproductive success. In other words, they favour any act of altruism. But the offspring will only favour acts of altruism where the benefit exceeds the cost discounted by the figure we agreed.
[speaker002:] How do you erm,
[speaker001:] Well, what, what I mean is, my genes for altruism are present in my body one hundred percent, okay. Any gene I had for making a sacrifice, on behalf of a... a sibling, are one hundred percent in my own body. However, because of the way it relates in this work, they are only fifty percent present in my sibling, so any sacrifice of gene me er, it's not my actual inquest for your finding of the problems, the reason is, this is something we did last term... in, in penaltriusm theory, so the others have got an advantage over you, they've already done it this time. I'm, I'm not surprised that, erm, you're erm,you you're having problems with it. But, it, it ba it's basically the penaltriusm idea that, for example, supposing I sacrifice my life, saving three of my siblings, okay?
[speaker002:] Yeah.
[speaker001:] I lose my life, so a hundred percent of my genes for altruism are wiped out.
[speaker002:] Yeah.
[speaker001:] But, I've saved three siblings. Now each of my siblings has fifty percent of my genes. So a hundred and fifty percent of my genes for altruism are saved in three siblings, compared to one hundred percent lost in me. That's a net gain for gene for altruism. Therefore it would be selected, cos that's what natural selection is. More copies of original. So the point I'm making is that... offspring will be prepared to make sacrifices under those conditions, where erm, the R is greater than C. But parents will want offspring to make sacrifices, wherever B is greater than C, and the parent is not concerned with the discount parameter R, but agreed on relatedness, because parents are equally related through their offspring. So any sacrifice by an offspring, that results in a net gain in reproductive success, is good news for the parent. Because obviously the parents' got genes in all its offspring. Can you see that?
[speaker002:] Yes.
[speaker001:] It's counter see you, the reason, the reason that this seems difficult to understand at first is we're not used to thinking of it that way. And the reason is normally we look at human relationships from one point of view or another, or assume that perspectives are the same, but clearly they're not the same, the perspective of an offspring is not the same as the perspective of, of the parent. That was "s basic insight, and it's a very important one. As I have said, I'll go over it in the, in the lecture in more detail, but this is key insight.... So does everybody see it now? Or at least got hold of the basic... as I have said, the best way to do this, is to sit down with a piece of pencil and paper and work it out yourself. Try and do the sums as it were and think it through, and if you do that, I think you'll see that er, it does work out this way And of course, it gets er, even worse if you consider questions like relatedness through parents, because clearly I may be related to my mother's sister's children, my cousins, er no it's actually nieces, because my mother and her sister share genes, but I'm not er necessarily related erm in the same way, erm, through er, my father's er relatives, for example, because although erm, because my er, my, my relationship between mother's kin and my father's kin is purely through marriage, so they have no joint genetic relatedness. So, although I am genetically related to my mother's brother's, or my mother's siblings' children or my father's siblings" children, the fact is, the siblings of both groups are genetically related to each other. And that produces further conflict, because the parents now take a different view. The parents now who they're related to. But their relatedness is not the same as the child. For example, my father is not related to my mother's er sister's children. Normally, if we assume, you know, completely non erm non-relatedness of marriage. So my father doesn't have a kin altruistic interest in me being grouped to my mother's sister's children. But my mother takes a very different view. She is related to her sister's children, so she has a genetic self interest in me doing things for my, for, for her er, female, er for her relatives and my father doesn't. So my parents er aren't gonna ag agree about my altruism. My mother will want me to be more altruistic to hers, than my father will. My father will want me to be more altruistic to his relatives, than my mother will. And this again will be a cause conflict. Sometimes is, and here of course is conflict between and married partners.
[speaker002:] How do we judge who's gonna be greater than we can't say that erm, how do we
[speaker001:] In practice, you mean? How do we do it in practice? Well, I suppose the simple, the short answer is, we don't know... exactly how we do it. The, the longer and more and less precise answer would be presumably, human psychology has evolved in such a way, as to allow us to make those kind of judgments that would normally be reliable. Er, I mean, for example, erm, if we... if you made us, well, let's go back to th your example. Giving up your sweets for your brother. Presumably, if you felt sad about that, what you're saying is, you weren't as happy about that as your mother was. Your mother presumably, who forced you to do that, was happier than you were about it happening, and that's what made you sad. [LAUGHTER] The, in other words, your emotions were reflecting these kinds of calculations. You seem to have an emotion, that made you resent making a sacrifice to your brother, and, and presumably, would have stopped you making it, if you'd been free to choose. Whereas your mother, presumably, had a different emotion, which made her think this was right and proper, or er, if it pleased her, issuing up this sacrifice. So it looks as if you, people's emotions have been tuned in such a way, that mothers look on these situations from their point of view and feel happy about it, and offspring like you look at it from their point of view and feel unhappy about it, and your emotions are the way the evolution has equipped you to deal with these problems. So if you'd been given a free choice, you wouldn't have given your sweets to your brother, would you?
[speaker002:] No.
[speaker001:] However,ho how, what was the age disparity between you and your brother?
[speaker002:] Four.
[speaker001:] Four. My guess is though, that if, if the age difference had been something like erm, seven or eight years, by the time your mother was asking you to give up sweets for your very much younger brother, you would probably have matured sufficiently and perhaps identified enough with your mother to see yourself playing a more kind of maternal role, as, you know the grown up sister. You might not have minded... giving up your sweets, because you, you'd have got a different kind of gratification. You would have felt oh, I'm being like mummy. And, and I think that kind of thing happens, in fact you notice it happening in families. Where there's a big age gap, between the children, the older child often will go along with the parental wishes much more, merely because it's much more mature. It won't be competing for the same resources. For example, it may not want the same sweets as, as the little kid, you know little kids like little kids' sweets, and grown up kids like more grown up sweets, they may like bubble-gum and things you wouldn't give to a little baby. So the very fact that the offspring are more mature, would reduce conflict, because the degree of value of the sources is going to be much greater, in other words, you could give up the sweet. The, the relative cost to you would be trivial, but the relative benefit to a much younger, erm, sibling of yours, might be much greater. And because you are so much older, you wouldn't see yourself as competing for the same resources, and you would probably have matured in ways emotionally, that would make you accept and identify with the parental values, rather than, than feel sad or, or resentful, because you felt you were more like your brother, as it were, and you were being discriminated against. Does that answer your question? I mean, it's not a very good answer, because frankly we don't know,th the full reasons for this, but...
[speaker002:] obviously some variations in
[speaker001:] Oh, absolutely, it would. And, of course, I mean, we have, have to remember, that when we talk about ageing altruism, this is just an abstraction. I mean, we're not, erm, we're just simplifying a very complex situation, and in fact, probably large numbers of genes are, are involved, and they're, there are probably complex interactions between different sorts of altruism. kin altruism will certainly function within families for reasons that we've just been looking at, but this will also be a fertile and erm, encouraging er, framework for sibling altruism. So it may be that elements of the sibling altruism will develop in families, too. For example, you might have been a mere, much more happy about making a sacrifice for your brother, giving him a sweet, if you knew that on other occasions, he would give one to you, and because you are related to each other. In other words, you met each other a lot, and w we know you had the kind of situations that... [tape change]