 Thank you, Chaplain Elvie, and welcome to this afternoon's session. Richard Ringham, I was sitting back here listening to the introduction, and we realized we couldn't hear a word that Chaplain Elvie was saying, so I don't know if it's good or bad, but whatever you said, thank you, Richard. Or should I not say thank you? You folks that are just coming in have no doubt been handed brochures concerning this Nobel conference, and if you've looked at it at all, you'll know that our next speaker is Professor Richard Ringham from Harvard University, where he's in the anthropology department, and you've also then, of course, noted that he got his academic credentials from Cambridge and Oxford University, and after getting his doctorate, he assumed academic positions at Bristol University, at St. Mary's College, at the University of Michigan, and most recently, of course, at Harvard University. You perhaps also noted that he did his doctoral work on chimpanzee behavioral ecology at the Gombe Stream Preserve, that is, of course, very well known for his long-standing chimpanzee work. Some of the things that the profile, if you've looked at the profile of Richard Ringham in your brochure that is not mentioned, is the fact that he's received the very prestigious MacArthur Foundation Fellowship, that he's recently a fellow of the American Academy of Arts and Sciences, that he has published or written five books over 80, some scientific articles, that he has spent most of his professional career in Africa doing field studies, and in fact, anyone who has traveled in that continent comes to have an enormous sense of admiration for someone who can do the logistical work of doing the research in Zaire, Zambia, Tanzania, Kenya, and Uganda. In fact, Professor Ringham has just recently returned from Uganda, where he is at the Kibali Research Station, where he is the director of chimpanzee research. Several other things that the profile about Richard Ringham does not tell you is some historical perspective about what his recent research endeavors are leading to. Let me just clarify just a bit of the historical perspective. I'll go back to 1975, when E. O. Wilson published his monumental book called Sociobiology, A New Synthesis, and in that book there were 27 chapters. 26 of them were widely acclaimed and recognized as hallmark work, and in fact subsequently have served as the foundation for the whole new field of sociobiology. But the 27th chapter, the chapter that was called Man from Sociobiology to Biology, created quite a ruckus. In fact, it was a rather nasty ruckus that erupted in that 27th chapter. Many of you would know that story, and I will not repeat that here. That was just two decades ago, and let me just, I'll get a quote out here to let you see what, for those of you who don't know what the ruckus is about. In that 27th chapter, E. O. Wilson says something to the effect that, here we go. He was just talking about the heritability prospects of human behavior. By comparing man with other primate species, it might be possible to identify basic primate traits that lie beneath the surface and help to determine the configuration of man's higher social behavior. This is just, seems to be a fairly innocuous, mild suggestion about the behavioral, the genetic basis of behavioral traits in humans. As you heard Sue Savage Rumba say this morning, we have come a long ways in 20 years, and indeed she demonstrated that very clearly. But let me tell you that the dust has not yet completely settled on this issue, just as a curiosity. Just four years ago, the head of the alcohol, drug abuse, and mental administration for the federal government was pressured out of his job because he made the suggestion that we can learn something about the roots of human violence by studying primate behavior. That was just four years ago, he was pressured out of his job. Now we have come to the point where we are now going to be able to read Richard Rangham's newest book called Demonic Males, The Apes and the Origins of Human Violence. I think luckily for Professor Rangham, he probably won't lose his job over that particular title because I suspect that a tenure, they have a rather better tenure system than they do at the University of Minnesota, right, at the present moment. In the Demonic Male book, Professor Rangham is going to show us some of the ramifications of violence and between humans and chimps, among humans and chimps, that we haven't really addressed fully yet. Yesterday, here at Professor D. Wall, I discussed various attributes of peacemaking among primates. Today, you're going to see or hear the other side of the coin. Please welcome Professor Rangham. Well, I don't know whether to laugh or cry. I couldn't hear much of what Bob just said. I picked up the occasional word. Richard Rangham at the beginning, looks, chimpanzee, profile. I'm reminded of Ernest Hooten, who was the famous physical anthropologist at Harvard, who would begin his courses by coming into the lecture hall in a marked slouch, sticking his jaw out. He did have rather a prognathus appearance, walking very gruffly across the hall and I think doing a little display and then saying, if any of you were ever in any doubt about our relationships to the apes, don't be in any doubt any longer. But on the assumption that the remarks were kind, thank you, Bob. And thank you to the organizers of this wonderful conference. My topic is violence, which not everybody likes to hear about. I am sometimes jokingly reprimanded by my colleagues, but why do we focus on this nasty topic? There are nicer things to think about. It's contentious, but I think it's important. And I think it's also intellectually very interesting because new data are emerging from genetics as well as from paleontology and behavior that are giving us a new slant on the origins of human violence. My perspective is one that many different disciplines and areas of thought have shared for a long time, which is that humans are very peculiar. I say humans, but I've now come to internalize the concept of the demonic male for so long that what I really think of is human males. Until relatively recently, the predominant area of the human male predominant area of thought about such deep issues as why are we so given to fits of incredible nastiness came largely from religion. And most religions see something special about humans, some equivalent of the fall. Humans doing something wrong and leaving a state of nature, which implies that nature is relatively nice, which is in contrary to the ordinary metaphors that we think about the beast in man, a beastly behavior, inhumane behavior, implying that it is the animals that behave in a nasty way. We are muddled, but of the importance and extraordinaryness of the depths and depravities of human male behavior. I think that no serious reflection can leave us in any doubt. Dostoevsky was, I think, in some ways the supreme psychologist of the 19th century, and the brother's Karamazov was his final contribution to thinking about the sources of human evil. And I sort of take the point that he summarized with, based incidentally on a lot of data, a lot of anecdotes culled from newspapers around the world. In every man he said, a demon lies hidden, the demon of rage, the demon of lustful heat at the screens of the tortured victim, the demon of lawlessness let off the chain. I don't say this in order to be dramatic. I'm not meaning to be at all. What I want to do is just to get us into the mindset where even though we're very nice people who are doing things that no animals could probably do, which is a sit politely for an hour and listen to somebody else, even though we are incredibly courteous and very pleasant to each other in ordinary conversation and in ordinary interaction, the fact is that given the right circumstances, most men will be prepared to do things that in ordinary circumstances they would be simply ashamed to talk about, whether it be killing or raping or battering. Biology has, in the last 20 years, had a revolution in thought that is now totally familiar to us all, often encapsulated as the selfish gene theory, in which it is easy for us to see why it is that individuals have been favoured by natural selection to use violent means to pursue certain ends. So in some ways it might seem as though the violence of humans is easily explained by a little biological theory. But one might expect on the basis of simply the grand theory of sexual selection that all males in all species should be equivalently violent to humans and it is patently clear that they are not and there are some species in which males are noticeably peaceable, in which they are very rarely, if ever given to any kind of violence. There are various ways in which males can compete for their ends and they don't have to be through violent aggression. The picture then that was the one in intellectual thought at the time when Jane Goodall started her studies was principally one which saw humans as very different and that picture was reinforced by the early chimpanzee observations, observations that certainly saw connections between humans and chimpanzees in the strength of the relationships, in the kinds of gestures that were used in chimpanzees in the wild, in the intensity of mother infant bonds and in what appeared at the time to be a very relaxed social life for the chimpanzees. This in the early 10 years was a time when intense mate guarding had not been seen, when males were not seen to fight over females, as subsequently it turns out that they regularly do when the female is at the appropriate stage of her menstrual cycle. So this then was what Robert Audrey called the Arcadian existence of primal innocence that we once thought was the paradise that man had somehow lost. And here is Goga at the end of the 19th century in 1897 in the painting that he considered his spiritual legacy summarizing this kind of view. This is a massive mural, it's called Where Do We Come From? What Are We? Where Are We Going? It's in French. And on the right hand side we see a small baby representing where do we come from in the middle? Day to day existence is represented by the character picking fruit. And on the left though a little dark there is an old woman representing death. And Gogan's feelings about this were represented in the middle just to the right of the figure plucking fruit is a very dark couple which are sin. It's human culture emerging into this picture and creating for Gogan a pessimistic sense that it is our very humanity that creates our evil. The picture of peaceful chimpanzees and depraved humans was changed as I'm sure most of you know in 1974 with the first observations of rather intense intergroup violence and the pattern of behavior that was seen then has now been seen rather regularly. It can start with a small party of males sometimes accompanied by a female if so she's likely to be childless leaving the center of their community range where they have been typically led by the alpha male and walking towards the boundary of their range and then sitting. The striking times are when the males arrive and do not feed on the way do not move to a food tree but instead just sit and listen. And while listening what they're doing is being responsive to chimpanzees in the neighboring range. If they hear a large party of chimpanzees or even just three or four then they may have an exchange of calls and then move back into their own community range. But if they hear just one that's when they can immediately take off in silent pursuit of that one they might hear one they might see one some many hundreds of meters away. And that's when sometimes you get these remarkable cases where with tremendous excitement with enormous enthusiasm for pursuing a victim they do tremendous damage to them enough it seems to kill them normally. So two or three hold one down and others are pound on top of them and so on a very deliberate business and then they retreat still intensely excited back to their own community range shouting displaying hitting tree buttresses exchanging all sorts of hugs and embraces. This was the first individual that was probably killed by other chimpanzees female and you can see maybe her hand on the top right hand part of the slide and they stretched arm as the body had been pulled down a slope and beaten apparently by other chimpanzees. Now in Gombe where the first observations were made it is a matter of considerable public knowledge that one entire community was wiped out over a period of four years and it has entered novels and movies it's something that we're relatively familiar with. I want to just briefly mention that equivalent patterns appear to be reasonably common. Here are chimpanzees in the Mahali mountains further south in Tanzania than in Gombe where the previous slides were. In Mahali Toshisada Nishida has seen many of the elements of the raiding into neighboring ranges. He and his co-workers have seen parties of males leaving their area going to sit on the boundaries and look into the neighboring ranges they've seen them charging towards their neighbors they have not seen truly vicious fights that can lead to or likely to have led to a death however they think that that's just a chance that they weren't around at the right time. They believe that the extinction of their community shown on the left hand side here males disappearing to the point where one community went extinct was largely due to the same sort of behavior as is known to have been responsible for the majority of deaths in Kahama. So here we have the two longest studies of chimpanzees and in both case a community has gone extinct in one case definitely another case suspected to be the result of this intense warfare like behavior. In Tai National Park on the other side of the continent Christof Bosch has recorded the frequency of territorial encounters as about once per month and as he has seen the number of males in his community dwindle he has feared for its continued survival as a result of the territorial encounters but he's also seeing death due to poaching and leopards and disease so he is not quite clear what is going on. I started work in Kibali joining his Sibiribasuta nine years ago and since then we have some nicely abituated chimps who have never been fed with bananas or other food designed to habituate them and for much of the time we have exactly the same picture that Jane Goodall and her colleagues presented from the first decade of her work namely a charming social relationships, relaxed scenes, intimate affiliative behavior, a lot of play, a lot of just delightful behavior of the type one would wish that humans showed all the time but we have also recorded border patrols, we have recorded raids into neighboring areas, we have seen males from the neighboring community coming into our area and these are the bones of young Ruan Zori, an early young adult male who was killed in 1992 on the edge of his range by males of the neighboring group as we can reconstruct from the evidence of flattened vegetation and the fact that we had had counter calling episodes for the four days prior to the discovery of his body and in a community also in Kibali Forest in Uganda where I'm working where chimps are being habituated for tourism a violent fight which appeared between members of neighboring communities led to the death of another male here in other words it seems as though wherever chimpanzees live flanked by neighbors they have the same experience of mixing a relatively idyllic life with occasions of intense violence so that to be in the wrong place at the wrong time means the risk of being beaten to death let me just briefly talk about the other apes the gorilla has long been characterized as the gentle giant and in the same way as with chimpanzees we have most of the time high 90s or high 99s probably very little aggression going on in the community in the stable group of gorillas but you are probably familiar with the fact that the males are competing for females they fight with each other the fights are often precipitated by one male leading his group in pursuit of another group that pursuit may go on for days sometimes even weeks at a time looking for opportunities to make an impressive charge and display into the group and a time to get past the defenses of the defending male and what he is doing is trying to impress another female into joining his group and sometimes this works a nasty photograph coming up of a female of an infant it was a female who was killed by an infanticidal male and her mother then transferred against our sense of what are proper emotions to the male who did the killing she joined his group the logic that may appear to explain why she should do so is that he has proved that he can kill her infant he is suggesting as it were to her that he has become a more likely successful defender of her next infant here is a male orangutan male orangutans adult males cannot be together without fighting this particular one is showing on his shoulder a wound sustained in fighting with another adult male orangutans are also famous for their rape berute may want to talk about this a little bit she was emphasizing to me today that the pattern of rape is one that doesn't appear to bother the females tremendously some people don't feel very comfortable with the idea that one should call it rape but it is the kind of behavior which in a human court of law would undoubtedly qualify as that that is to say that a male is controlling a female's ability to escape until he has a sexual intercourse with her and and then he will release her it is not normally the fully adult males it is the small adult males that do this behavior but like infanticide I want to emphasize that here is a behavior that is shown in chimpanzees it is rare in in chimpanzees but it does happen sometimes that a male is refused by a female to whom he has made a sexual overture maybe it is because she is his sister but maybe it is because she just doesn't like him for some reason now some remembered slight from a few days before or whatever and he will pull her down slope and pummel her until she meekly approaches him and with gestures of submissiveness offers herself and he has sex with her so these are things which are unpleasant to think about but which are striking because they are relatively rare in the animal kingdom as a whole and so it seems odd that in humans and our close relatives so many examples of this demonic male behavior should appear it is particularly striking when you move further outside the great apes to the monkeys because in general when you move to monkeys you find something a little bit different you do not see males behaving violently to the exclusion of females here we have something which seems immediately unfamiliar the concept of fighting females but to recess monkeys fighting females is a perfectly understandable concept if if recess monkeys are going to be asked about that that is to say when we have intense intergroup aggression involving recess monkeys those individuals who are at the center of the battle those who are leading it those who are most intensely involved are the adult females and the same is true in a number of other species around the world in other words there is no natural reason why adult males should be the fighters it is not a simple consequence of males being bigger than females or of males wanting to have sex with females there are species in which you get all sorts of different combinations and it therefore presents a puzzle to us to work out why it is that we get our particular combination in our particular species and our relatives and here we have bottlenose dolphins in which it's recently been discovered that we have very strong male bonds they are male bonds but they are not expressed in quite the same way as in chimpanzees and humans they are used to coerce females to herd females for as long as three weeks at a time and then to mate them but there is no evidence yet that the males use their bonds in violent attacks against each other who knows it may come out though so there is something special about chimpanzees here we see a chimpanzee that's just been beaten up by others in fact this this claim I'm just about to make may turn out not to be true but at the moment it appears to be true that there are only two species of mammals in which males form strong bonds with each other share a community and then move out from that community to make raids into neighboring areas and deliberately damage and kill members of those neighboring areas of those neighboring groups and they are humans and chimpanzees and even if there are other species that do that the point is it's quite clearly very strange that we should share these nasty patterns with our close relatives link it to rape and battery as well and we have a poor history so why is this the question that immediately arises is is there something to do with evolution have we simply inherited some tendencies or is it not is it chance and if it is to do with our evolutionary relationships is it functional or is it just the meaningless carrying on of something that evolved several million years ago and is now expressed even though it doesn't make sense I think that the evidence is that in fact this is something that has come down from common ancestry and that it reflects the fact that there are shared evolutionary forces at play but I also think that it's too early to be convinced about that hypothesis and that we need to understand it better so what I want to do today is to go through the evidence for why I think it is a a shared derived trait that has evolutionary significance one of the reasons that it's really rather clear that this is not simply the result of phylogenetic inertia meaninglessly retaining in our current forms a pattern or a set of patterns that evolved some millions of years ago is of the discoveries of the bonobo because as we've already heard to some extent bonobos show marked contrast to chimpanzees in their expressions of violent behavior the bonobo was first watched in 1973 and simply extraordinarily late appearance on our intellectual scene in fact it almost coincides with the discovery of violence among chimpanzees they were first literally seen by a scientist in the wild Takayoshi Kano six months before the discovery of the intense male violence and in every way the bonobo shows less violence than chimpanzees it shows less violence in intra group oh excuse me just to show you the relationship the geographical relationship which I think you've already seen but I just want to do this in a way which emphasizes a puzzle about chimpanzees and bonobos the puzzle that I want to try and answer which is that because of the peculiar shape of the Zaire River with the bonobos the bees living on the left bank and the chimpanzees the seas living on the right bank it so happens that they live in an island of forest which is both north and which has chimpanzees both so the north and the south of it and to the east and to the west which suggests the habitats of these animals should be really extraordinarily similar and yet we have this very different behavior even though these two species look very similar in the intra group relationships males are not given to any kind of battering of females of the type that I've mentioned for chimpanzees they ask for sex kindly at all times in intra group relationships the males do not compete intensely with each other they certainly compete there are dominance relationships among males they will chase each other they will have physical contact but they do not have such intense and brutal physical contact as occurs among males in bonobos there is a particularly striking difference in intergroup interactions now people are always worried that maybe we haven't seen the pattern of really intense intergroup interactions in bonobos that have been seen in chimps because in any animal this is going to be very rare well that's possible but nevertheless it is very striking in bonobos that it is possible for two neighboring groups to come together and exchange social interactions to be friendly together for long hours even at a time I well remember the sense of of shock when I first saw a film of this taken in Wamba in Zaire of two neighboring groups in which females were mating across the groups and the males of each group were doing nothing to try and stop those males from mating and females were also grooming with each other across the groups to me as a chimp watcher from Gombe and Kibali that sort of thing is inconceivable so even if it turns out that there are going to be discovered rather violent interactions between groups there is nevertheless an enormously greater capacity for peaceful interactions in this species the females of bonobos are notorious for the prolonged sex sexuality and for the fact that sex plays such an important role in ameliorating tensions within the group the behavior of females also differs from chimpanzees in the wild in a very important way which is that if a male does get out of hand and attack a female then females are known occasionally to charge back at the male and under some circumstances will do so as a gang so a female can give a call which leads to many other females in the party all joining her side and mobbing a male it's early to say but my sense is that this is a very important key in the evolution of the changed bonobo system because what it does is to keep the males properly in place I think it may be responsible ultimately for the fact that bonobos are able to use sex as a medium of communication because males are much less given to violence towards females knowing that they have the potential for females to gang up on them and keep them in control but those are somewhat speculative issues I want to leave it for the moment with the idea simply that there is a marked difference between bonobos and chimpanzees in the level of violence both within groups and between groups I just like to measure one other mention one other way as well this is not an easy slide to see but in the bottom right hand corner you have a chimpanzee climbing up a tree and near the top just to the right hand side you see a group of red colobus monkeys all very tightly bunched being very alarmed by the approach of the chimpanzee years ago Raymond Dart suggested that there was some association between the evolution of hunting in humans and the evolution of intense intergroup aggression and that was later poo pooed by the ethologists of the 1950s and 60s when it was noted that the neurobiological control of predation in cats has got nothing to do with intraspecific aggression and the doves were very aggressive and and yet are not predators and so for many years we've thought that predation and hunting that hunting and intergroup aggression have got nothing to do with each other I suggest that that may be wrong at any rate it is extraordinarily striking that even though bonobos like meat and even though bonobos do catch meat antelopes on the forest floor and even though bonobos sometimes catch monkeys and play with them rather like dolls they have not been seen yet to chase after monkeys and attempt to catch them well doing so is a behavior which involves intense excitement intense aggression it would seem and is somewhat like the patterns of behavior that you see when the chimps are going after a member of a neighboring group and I believe it's possible that the reason that bonobos do no hunting of monkeys is that they come from an ancestor that used to do it but that that behavior has been suppressed in what I believe is the suppression of intergroup aggression in the species and lest you think that it's simply to do with meat eating it is striking how often in the chimpanzee population where I work the chimps catch monkeys and then leave them and go off and catch more it's an intensely repetitive behavior I'm reminded of Americans in the deer hunting season they are going off to do their hunting not necessarily because they are hungry but because it is really fun to go after the kill here is a black and white colobus monkey it's been killed by chimpanzee it puts it down and goes off and tries to hunt again sometimes they do a bit of eating put it down and then go off to hunt again here are two baby red colobus monkeys that a male caught ate a little bit put them down nobody else came he didn't give them to anybody else and he went off and hunted again and he caught another one and then he let someone else take that one and then he went off and hunted again they really love to do this maybe what we're seeing is the expression of a tremendous interest in an aggressive context humans chimpanzees and bonobos were presented with an extraordinary triad and we have to work out what their evolutionary relationship is in order to be able to make sense of what we see the evolutionary relationship is a picture that is changing and is a picture that is still unsettled I think it's going to take a few more years before we get a totally confident sense of exactly what our ancestors have looked like people sometimes they exaggerate the degree to which we are related to our close relatives even though we have 98.6 percent of our genes in common that doesn't necessarily mean that we are literally the same species we have to be cautious and look at the few remaining genes that are different and work out exactly what they tell us well everybody is probably familiar now with the cladogram that's already been shown in this conference several times based on DNA findings that go back to 1984 but have now become really totally confident the whole of the mitochondrial genome has been sequenced about a dozen nuclear genes have been sequenced nucleotide by nucleotide and the level of statistical confidence that puts us in this branching order with chimps and bonobos last and then humans and then gorillas is now so strong that I think we can take it as certain and really it's only been in the last two years that that degree of confidence has properly emerged the question is when we see this cladogram what does it mean about reconstructing our ancestors if we take the human line and go back for two million years we have an excellent fossil record of still a human species if we go back for another two million years after that we have an excellent fossil record though less good as we go back to four and five million years of the australopithecines which I like to call the woodland apes it's clear that they were living in a sort of savannah woodland and I think it's clear that they were apes based on the fact that their brains were still the size of modern great apes question I'd like to address is what was the common ancestor like of humans and chimpanzees and bonobos and I ask this because only a few years ago it was thought that humans descended from a line that went from the woodland apes straight off into the myosene apes thick enameled species that were found in the myosene of Africa the largely deserts of Africa and that had no place for the modern african apes and that therefore meant that we saw an ancestor at six million years or so that was already a desert adapted species or a woodland adapted species that had long been separated from the modern great apes but now suddenly the paleontologists are forced to think again as a result of the genetic data and we can ask a question about what that animal was like I'm going to begin by thinking about bonobos now Sue Savage Rumba said this morning that she noted great similarities between bonobos and humans and there are indeed many but if we do the clodistic analysis if we say let's compare chimpanzees and bonobos and where they are different ask how those differences compare with the gorilla what we find is that the chimpanzee is consistently more close to the gorilla than the bonobo is so for example the form of the scapula the shoulder blade has been examined in detail and the chimpanzees is basically a small version of a gorillas but a bonobos is somewhat different and the same is true whether we're talking about blood groups or chromosomes or sexual physiology or the overall growth pattern so I think of bonobos as a species that has been derived away from the chimpanzee gorilla pattern and that the similarities that we now see between bonobos and humans for instance in those emergent properties of of language are to some extent chance I showed this picture for a different reason from the one that Sue showed it today Paul Dushayu was collecting a nasty word apes in Africa in the 1850s and one of the species that he came came back claiming to exist was an animal called the kulu kamba so called because of its cry which sounded like kulu kamba and the kulu kamba was he said a species well there were many species described there was many as 20 species of chimpanzees described in the early part of this century most of those were thrown out but the kulu kamba remained there were skulls of this species there were photographs of specimens there were two kulu cumbas in the Holloman Air Force base only a few years ago people were not sure what the kulu kamba was some people said it was a subspecies of chimpanzee some people said it was a hybrid between chimpanzees and gorillas some people said it was a small gorilla it turns out that the chimpanzee that the kulu kamba was none of those it turns out that it was just members of that particular subspecies of chimpanzee the central subspecies are where those chimpanzees live but the reason that people were confused about it was interesting they were confused because large chimpanzees to some extent take on the characteristics of gorillas anatomically to a large extent a gorilla is a hypertrophied chimpanzee if you extend if you conceptually extend the growth of a chimpanzee it becomes very gorilla like and many other things follow the larger animal is better able to digest lower quality foods as gorillas do digesting lower quality foods it is better able to live in stable groups where the food patches are large enough for it because they are lower quality and more abundant in those larger groups patterns of sexual physiology and sexual anatomy and sexual behavior change and so on so a lot flows from that if we take as most anatomists do the view that gorillas can be thought of as a large chimpanzee then we come back to our cladogram and we say what kind of animal was it that was living at the time that gorillas and chimpanzees separated eight to ten million years ago it looks as though the characteristics that we now see in those two species have been extremely conservative i think that we can look back even eight to ten million years ago when the molecular dating puts the split of gorillas and chimpanzees as having apes that even then were black haired and large mouthed big bellied they were knuckle walking they had thin enamel teeth they were loud voiced and they were fruit eating and if they were more like the size of a chimpanzee then they'd probably lived in a fission fusion society like chimpanzees and bonobos and if they were more like the size of a gorilla they were probably living in more stable groups but everything points to them being more chimpanzee like because prior to that we have animals that were relatively chimpanzee sized and subsequently to it we have animals that were relatively chimpanzee sized all of which is to say here's another example of an animal that was chimpanzee sized namely the australopithecines close to that point at which the chimpanzees and human lines split so it seems as though we have a very chimpanzee like ancestor at around five to six million years ago and that is a view that is only possible as a result of the recent genetic evidence but also only possible because of the remarkable fact that gorillas and chimpanzees do look so extraordinarily similar in their anatomy it's very rare for such species to exist it suggests that chimpanzees have been a conservative species changing very little just having occasional episodes of punctuation where new species are carved off if that is the case it suggests that our ancestor that lived five or six million years ago was a species that may well have had the same kinds of characteristics in terms of social behavior that chimpanzees and humans now share you hear my hesitations clearly there are speculative parts to this argument but nevertheless i'm trying to present a clean hypothesis which gives us something to work on but aside from just the evolutionary pathways we can address another angle what is it that's responsible for the pattern of violence why is it regardless of the evolutionary pathways that there should be the tendency to attack members from neighboring groups in these two lines let me point to just three things first of all chimpanzees living in a fish and fusion society have got times when they are vulnerable and times when they are safe there are times when they are able to travel in relatively large groups but repeated studies in different areas all show that when fruit is scarce individuals split up into very small groups and sometimes it can happen that fruit is abundant in one area and is scarce in another and those one may think should be the times when it will turn out that members of one group make attacks into neighboring groups when they have for essentially chance reasons an imbalance of power working to their advantage that's a result of the kind of foods they eat and the kinds of environment they find themselves in here's another fact we know that the males form very strong bonds with each other we still don't have a really confident theory of why they do so but there is increasing confidence in a cost of grouping hypothesis which says that the animals that are able to travel together are the ones that form the bonds and the ones that travel together are the ones for whom the cost of travel is relatively low when a mixed party of chimpanzees like this walks a long way when a mixed party like this assembles they have to walk further than they do when they are alone because they are eating up the food sources as they go and they have to go further and what you see is that in such a party the mothers with offspring drop out in order to go alone they are slow and the work of travel is harder for them mothers without offspring are quite happy to join those groups but the mothers who have their offspring whether the offspring is walking or whether the offspring is climbing on them it's harder work for those mothers the cost of grouping is higher for them they spend more time alone but the males are able to be social with each other they form strong bonds and they use those strong bonds in alliances against others there's one other point i'd like to make in addition to the vulnerability and the fact that males are able to form bonds with each other and that is that in animals that have complicated kinds of social relationships aggression is not just over resources it is over the relationships themselves we know that relationships are very important in all sorts of ways i'd just like to mention one recent discovery we collect urine from chimpanzees by taking it with a pipette off the leaves and what we can now see is even with very small samples of urine per individual male a very marked relationship between the level of testosterone and their social rank where the highest ranking males have more testosterone rank is extremely important for male chimpanzees they are repeatedly working to elevate themselves in rank and probably the highest testosterone levels reflect that we can be relatively confident of the the meaningfulness of these relationships because of what we see when there are changes in dominance rank as the rank changes for three individuals here in relationships the line shown in the previous slide we see that the males find an appropriate position for their new rank probably the testosterone is serving to sustain the aggressive behavior that underlies their rank position they maintain this through frequent charges at each other and the importance of rank appears to be very great though it's still not confidently known in terms of giving reproductive success but certainly chimpanzees act as if it is in the sense that they are willing to attack each other even when there is no food or females at stake in order to achieve higher rank higher rank appears to be something that dominates the lives of male chimpanzees in the wild we can look at male chimpanzees and say the chimps are competing to be the top animals they are able to use male bonds they are able to take advantage of times when there are vulnerable individuals because they are traveling alone to go out and remove potential rivals if we go back in time along the human line it is interesting to ask whether or not those features are likely to have been found in our ancestors hunters and gatherers today have a rather chimpanzee like system in the sense of efficient fusion existence with individuals sometimes traveling alone and sometimes together male bonds are also very important it seems likely to me that the essential ecology the essential ecology from the point of view of the grouping patterns of our ancestors is likely to have been the same in the african savannas the essential roots foods eaten during times of food scarcity are roots and i believe that the australopithecines can be characterized most confidently as root eaters because their teeth show remarkable characteristics different from almost any other animal but similar to a few such as the root eating pigs they show enormously thick enamel as you see in the top of this cross-section of a australopithecine molar compared to the thin enamel of most primates such as this ape and that is just a passing reference to the fact that to the extent that we can reconstruct the ecology of our earlier ancestors i see them as being forced to use foods that would impose a fish and fusion system in a similar way to chimpanzees and foraging humans today if we can hesitatingly begin to understand the rules that push chimpanzees and humans towards being able to take advantage of potential victims then what's different about bonobos one might want to take this at a physiological proximate level there is some evidence that the level of testosterone that is found in different species is related to the level of investment in aggression in those species here we see that species that have bigger teeth for their body size or for in this case the size of the females have more testosterone in the males which maybe helps to give confidence to the idea that this is a real result that when you look at zoos and institutions in this country bonobo males have less testosterone than chimpanzee males but i think that the level of testosterone should be seen as being adapted to the patterns that we see in the apes just as it appears to be adapted to the rank changes of the individual chimpanzees the more fundamental questions are the questions about the way they live the striking thing about bonobos is that even though they live in an area surrounded by chimpanzees their patterns of grouping are a little bit different and to some extent their groups are larger but even more consistent a difference from chimpanzees is that they are more stable how is it that they are able to be more stable i'll briefly address that but why is it important that they are stable if they are stable then we do not have lone individuals who can become victims if they are stable we have females who can form alliances together to suppress the aggression of the males the stability of the bonobo parties maybe the same sort of push that enables other primates to avoid the patterns of aggression that we see in the chimpanzees and humans why is it that they are stable this species eats a lot of pith and that may seem a totally trivial observation but the piths that bonobos eat are distributed widely on the forest floor they are relatively abundant and much like here is a picture of where trees have been cut down revealing the herbs that produce pith on the forest floor much like gorillas if you are a pith eater in an african forest then other things being equal you're going to have enough food that you're not forced to split up when the fruits are scarce you can stay with your partners you can maintain those alliances that are so important as defensive alliances against violence and yet chimpanzees do also eat pith i think that pith eating is a central feature of the evolution of our clade and here we see the river that separates the bonobos from the chimpanzees what is it that should be so different from the left side and the right side of this bank that has enabled bonobos according to this hypothesis to eat so much more pith they can live in more stable groups and develop the kinds of relationships that enable them to suppress the violence i think the key feature is that only gorillas are in the the gorillas are only in the area where chimpanzees live gorillas are pith eaters bonobos are big pith eaters and bonobos are in an area where there are no gorillas to compete with them for these foods the result is the bonobos are able to have relatively large amounts of this a predictable amounts of this in their diet and to live in the kinds of stable groups that gorillas do and we can then go on and speculate as to why this should be and i think this is rather uh attempting to relate to an episode in hominid evolution we know that the forests have been contracting and expanding over africa for millennia it is reasonable to think that at periods during the last 10 million years gorillas and chimpanzees have been both sides of the zaire river and we certainly know that there have been periods when it has been dry and cold and the forest has contracted intensely and i suggest that around two million years which is one of the times that the geneticists give us for the evolution of bonobos there was such a dry period that the herbs died out the herbs that sustain the gorillas and yet they survived in a few places and those few places are the places where now in dry country we only we see the piths and those are the mountains but there were mountains only north of the zaire river south of the zaire river there aren't any and there weren't any and so animals totally committed to pith eating died out altogether well later warm wet weather came back and the piths rapidly returned and suddenly now you have a fruit eating niche a a pith eating niche now the chimpanzees just like chimpanzees north of the zaire river today can be hypothesized to have survived quite happily in areas without the piths such as in Senegal and western towns of near where they occur today in areas where there is savannah just intersected by a few fruiting a few forest covered streams so the chimpanzees can be hypothesized to have continued living on at the two millennia dry phase and then they find themselves in an environment in which there are both piths and the fruits and that i suggest is the way in which bonobos evolved it's a just so story at the moment much of this is ultimately testable through an improved fossil record but what i want to do is to give a sense of the spirit of the intellectual adventure looking for ecological causes that have ultimately social consequences i think one of the reasons that this is an attractive and interesting idea is that it may be that the drying event that led to the loss of gorillas south of the zaire river and ultimately paved the way for the bonobos could be the same drying event that converted australopithecines to hominids further to the north and east of the forested regions we go back to our cladogram i suggest that what we are looking at is that as the lines from chimpanzees and humans converge we have a five or six millennia ancestry of fish and fusion societies based on foods that were irregular that caused parties to break up to be occasionally victims whether to aggression leading to death or merely to the kind of violence that was leading to sexual coercion or intense rank changes that at around two two and a half million years ago the bonobo line split off and gave us a different kind of picture now it's easy while focusing on the particular problem of violence to get carried away with the idea that these species are programmed to be violent at every single occasion well i just want to come back to the point that obviously we're not we're talking about tendencies that might turn out to be expressed in very particular circumstances just how particular those circumstances are we still don't know i want to emphasize the other side of the story though and i want to do so through a story which just emphasizes that sex differences are are not acute here is a seven-year-old male kakama who three years ago showed me that chimpanzees in the wild have imagination without being brought into captivity and having it nurtured for them i was following him and his mother at a time when they had been alone for several days and they were alone then kakama was very bored he displayed towards me a couple of times and when he got to within about a yard he ran away and the second time when he ran away he fell and straddled a little log and did a somersault a couple of somersaults with the log and then walked on in the forest holding the log by one hand and letting it bump over the ground as he went and they went on down and he followed his mother kabiroli into the forest and i lost sight of them and it was a few minutes more before i was able to catch up with them and i saw or i heard that they were feeding in a tall tree and when i finally got to a point where i could see where they were i saw that kakama was sitting eating fruits and he had the log on his knee and a few minutes later he shifted his position and moved a couple of yards and then pulled the log with him and every time he did so every time he shifted position he kept on taking the log and his mother 20 minutes later went off to make a nest she was in her sixth month of pregnancy and she was feeling tired and regularly rested a lot during the day so he knew that he was going to have to rest and he went off and made a nest too and when i could next see them i saw i couldn't see kakama in his nest because it was above me but from the angle i had i could see that his feet and his hands were above himself and the log was resting on the palms and just like mothers sometimes do with their babies he was just gently pushing it up and down and then he took the log into the nest with him and i could see no more 10-15 minutes later kabiroli got up out of her nest and we expected well i expected that kabiroli was going to climb down and and walk off but she didn't she just sat looking out over the forest but kakama apparently had the same expectation that i did and he got up out of his nest and and then he got bored again while she was sitting just looking out over the forest and so he made another nest but this time it was a peculiar nest it was a nest not of a type that chimpanzees make for themselves because instead of being out on the end of a branch it was tucked in in a cleft of two branches a rather awkward nest and then he put the log into the nest he kept it with him for all of the time in that tree and then for another three or four hours the fact that he put the log into a nest seems very peculiar i've only seen one other chimpanzee take an infant and make a nest and then put the infant into the nest without getting into it himself and that chimpanzee was kakama having done it a few years before which tells me that kakama had the imagination to see this log as a doll and he was stepping out of his sex roles in this behavior it's interesting to me incidentally that we've now seen more observations of log doll use and all three of them are in kakama's family it's himself again and two now by the younger sister that was born to that then pregnant mother and there is his log and there is kakama now playing with an 18 month old infant who is unrelated to him just a friend so when i look into the face of a male chimpanzee i just want to emphasize that most of what i think of when i see that face is behavior more like kakama's a face that is full of mental imagination and the potential for play that there is just a part of the mind that is given to the violence now some people say well so what if chimpanzees and humans share these patterns of violence Stephen Jay Gould in his column last month in natural history said what's the point in talking about this we've always known that humans have got a capacity for violence this doesn't say anything for us now but the way that we've always thought about humans is having a capacity for violence has been that it was something specially human and the fact that we see such a similar set of behaviors in chimpanzees clearly gives us pause to think that the underlying causes may be the same France yesterday said we shouldn't focus on our bad side that's only half the story maybe the more interesting side is the good side the side that leaves us to be moral but the control of behavior the reconciliation and consolation that we see so nicely developed in the apes is something that is only necessary because of the intense violence that we do occasionally see the human career is not a pretty one we still for all our advances have appalling wars and around the world women are mistreated sometimes in ways that government sanctioned with appalling regularity we cannot afford to simply sit back and say we are civilized species we have managed to do well let's just forget about these difficult sides of our past the attitude that says we should see no evil hear no evil is one that it's easy to be attracted to but i think it's very dangerous this particular postcard comes from Yugoslavia the problem is that it doesn't lead to any immediate solutions but at least i think it can help get us thinking and i think that in bonobos the fact that females form alliances which certainly sometimes have the effect of suppressing male violence is a kind of clue as to a way that we can help move France said that th huxley was wrong in asserting that the ethical progress of society depends on combating the cosmic design but it doesn't seem to me that the cosmic design has done too well it seems to me that we do need new ways to combat the problems from our past those ways will doubtless be something more to do with politics than with biological philosophy but i think there is one final sort of rather nice way in which we can think about the impact on ourselves of posing questions about humans as compared to the apes the traditional religions of the world have almost without exception been religions that fit right in to the old them and us problem that favor the in group at the expense of the out group what we need for the future i think our religions that truly unifies the ancestor worship that has been so characteristic of people throughout the world is a system that unifies people by reflecting on our ancestors and making us all kin fictive kin descendants of those ancestors i think that at the least what we can do by thinking about humans as species sisters to the chimpanzees and bonobos is that it serves to unify us all thank you take about 15 minutes for questions okay ladies and gentlemen ladies and gentlemen will take about 15 minutes for questions and then there's coffee out on the on the mall out in front of christ chapel and then we'll come back and we'll start the music at 3 30 so we'll give you another seven minutes there i was a huge in group oh thank you thank you professor ringham uh first i would like to encourage any of the panel here to make any comments that you'd feel it be appropriate at this time while we're picking up questions from the audience yeah of course i just wanted to say what i said to richard rangham this morning and i stayed up late last night reading his book uh demonic males and now i'm waiting for his even more important work called sainted females are they going to form alliances well i'm i'm jaundice in my view about males but i'm not starry eyed about females either let me emphasize that women are perfectly capable of very nasty behavior themselves so i won't go into details but actually i think the there's another equivalent of demonism if demonism in humans is interesting to focus on because it's a quality that's relatively exaggerated and is has enormous impact on society and is somewhat different between the sexes then i think the equivalent is that we should be thinking about erotic females thank you uh yes go ahead uh you talked a great deal and beautifully so about physical violence uh at the human level we know that a lot of the violence uh is verbal and a lot of it is legal in terms of laws passed in various ways or decrees made uh what evidence would you have at the uh in your from from your studies if any about how vocalizations of males and or females might in fact be as violently intended as what many of our words and laws are at the human level well i'm probably going to pass this question i mean basically the answer is i don't have much sense that the vocalizations of chimpanzees or bonobos but i don't know much about bonobos um are able to call up alliances in the same way that that verbal aggression does in humans i mean so much of verbal aggression is implicitly calling up allies who can help come in on the side of one individual or another i think that uh the use of vocalizations in patterns of aggression is relatively like most animals in apes but i try to think as i go france can you comment on this you're right most of the vocalizations are either to do bonobos are interesting they're different from chimpanzee but most of the vocalizations in chimps have to do with either intimidating each other or or calling in help if if you have potential allies allies around but i think is interesting in bonobos is that you see um what i call contest hooting between males sometimes i don't know if you don't have two adult males but if you have two adult males and i saw it recently in berlin zoo again you get these very rapidly alternating dialogues that are going on while they are charging past each other and so there seems to be more in exchange of let's say emotional state very finely tuned emotional state going on in bonobos than in chimpanzees chimpanzees pretty rough in their behavior uh so it's not vocally done mostly it's mostly done by intimidating physically and showing how strong you are and so on may i use this occasion to ask you a question i think huxley was very wrong huxley basically said that we could combat our nature by extra natural forces so we could use our intelligence or culture or whatever language maybe to keep our bad human nature in check so demonic tendencies or whatever you would call it i would say the only way to keep them under control would be through processes that tap into human nature to some degree and we have all the potentials we have all the mechanisms to do that so that's a very different view where you say that within human nature that is given both these tendencies that we worry about but also the solution to problems potentially there and it's just a matter of well it's not a simple matter but it's just a matter of reshuffling this and creating the right circumstances to make it possible to keep certain tendencies under control so actually was wrong well thank you for that clarification but but if for instance it's going to take some system of world government to control international violence does that mean huxley was right or wrong i don't know you emphasized female alliances i would not take margot tature as the head of that government probably i think we'll move on thank you sue did you have a comment that you wanted to make uh yes i just wanted to uh echo the comment about uh richards book it's an excellent book and whether or not he writes one on sainted females uh it's a wonderful example of a scientific mind trying to do it's a very best job at wrestling with the most complex problems that we face and i highly recommend it but the question i i wanted to ask i've always been fascinated by the story about the log the log and i think it's clear that it's an instance of imagination but what i want to ask is since you follow these apes around with your binoculars and maybe your backpack and maybe your clipboard i don't know what all you take with him but might kind of look like a log and since he was displaying at you at the time that this happened and since he was watching you are you sure that he wasn't imagining he's you it's a wonderful concept but i think that you're also implying that he was a little bit stupid we have a number of questions for the perhaps we'll we'll move on um can you hear me all right thank you does our need for excitement increase our aggression how is excitement related to aggression would you care for me to repeat that or uh no no i'm just trying to think um i i can't find an easy way into our need for excitement being related to aggression but i am very struck by the enormous excitement that is shown by human males both in war and in hunting the the accounts that you read by by soldiers whether from our wars in this century or prior men get incredibly pumped up and it seems very like the experience that they have when when chasing down animals whether that relates to a need to excitement i don't know but i think would be fascinating to know more about the um the physiology of this whether in fact contrary to the lorenzian position there may in fact be some great similarities in the parts of the brain and the endocrine systems that are involved i i think chimps are really remarkable in that is that and bonobos don't have that to that degree and gorillas don't have it to that degree is that they they get all worked up and they it's almost like they enter an altered state they are in a very different state at some point and i'm sure that's involved in the hunting it's certainly involved in high levels of aggression it's also involved in excitement that they have over food and we often call a chimpanzee an excitable species for a good reason because they are a very excitable species and they enter into a state where they seem to ignore everything and sometimes you get males who are low ranking and even forget that they're low ranking and get into all sorts of problems because they are in that altered state where they cannot get easily out of it it's almost like a trans like situation and it's maybe something we share with them maybe not to the degree that chimps have it because it really seems extreme but there must be something physiological going on otherwise they wouldn't be like that i'm sure that perhaps leads us into several questions that we have here related to the same thing about which comes first in male chimpanzees and humans high testosterone levels are high social rank in other words does a high testosterone level result in high social rank or does high social rank induce higher testosterone levels and then the other some other question relates that how does human male testosterone compare to a testosterone yeah we know amazingly little about this and the reason is that the methods for assaying testosterone have until recently required catching the individuals and to do that is a risk that you certainly can't take the wild chimpanzees what we use is the the urine method which has just recently been developed by Cheryl not the problem with that is that you can't compare it very directly to the data from humans because all the published data from humans tend to be from serum so we're still just in the early stages but i think that it seems much more likely that the testosterone responds to the social strivings of the chimpanzee however we will see we will be able to to monitor what is going on and see which comes first as far as the comparison between humans and primates it is possible to some extent to make a comparison but one's going to be very careful because the context affects testosterone levels so hunters and gatherers have very much lower testosterone levels than USA men and this is probably because it is related to nutritional state and the degree of immunological threat and so on however having made all those cautionary remarks the bottom line at the moment is that American men fit around the position of a gorilla or a chimpanzee if food is a prevailing factor for chimpanzee violence what you surmise is the reason for human male aggression in the forms of rape murder and battery well i think the common thread seems to me to be a vulnerability of the victim or i mean a common thread and and that applies to both species so it's not so much anything directly to do with food as the fact that individuals find themselves without allies and in some circumstances the reason they find themselves without allies is that they have been forced apart by ecological pressures so why is it that orangutans are subject to rape like behavior and chimpanzees because the females do not have allies to protect them what do chimpanzees or other apes do with individuals who are regarded as too aggressive sorry i'm sorry what do chimpanzees or other apes do with individuals who are regarded as too aggressive well i don't think there's any social sanctions if an individual is too aggressive for his own good then i you may lose respect i it's not something i've seen in the wild i guess france have you seen something a little bit about the wild i remember that goblin when he tried to make a comeback you know goblin was deposed in gamba stream and he was a very aggressive male extremely aggressive male maybe and pussy who's in the audience can say something about it but anyway goblin was deposed and tried to make a comeback and was soundly defeated and by a mass attack by the whole group and jane goodall commented on that that if he had been a nicer alpha male maybe he could have gotten back in but he was obnoxious so to speak um you know if if the alpha individual is overly aggressive there's often very little that individuals can do against that unless in this particular case uh if lower ranking animals are overly aggressive they're certainly sanctions against that yes certainly someone will step in and do something about that thank you very much at this point we'll call it call it closed to the question and answer period it is now three o'clock we'll reconvene here at three forty so we'll give you extra few minutes to have your coffee and and snacks so we'll see you back here at three forty