Pathfinders: Bonobo Fides

When the human genome was first effectively sequenced in April 2003 and the surprise discovery made that humans have only 30,000 genes, scarcely more than other primates, some people were encouraged to suppose that the nagging debate between nature and nurture might be solved once and for all. Humans could not be genetically disposed toward all the multitude of obnoxious acts they committed,  because they had no stock of extra genes with which to be so disposed. The seductive conclusion is that any human behaviour not found among primates must therefore be a simple matter of environment.

Not necessarily. As the developing field of epigenetics has begun to demonstrate, the whole can be greater than the sum of its parts. Combinations of genes can produce phenomena that could not be predicted by analysis of the characteristics of the  individual genes. A piano in the hands of a baboon or a human still has 88 keys, but the baboon will give us a cacophony whereas the human may give us a concerto. The discovery, last month, that humans are more genetically diverse than anyone expected, has done even more to throw the ‘nurturists’ back into turmoil, and given the bio-determinists extra room for manoeuvre.

Reading the language of the genes may help us stamp out certain inherited illnesses for good, but it is debatable whether it can ever say anything meaningful about who we are. Studies of identical twins separated at birth show interesting variations in behaviour, yet the results remain essentially random and open to interpretation, because it is not possible, or ethical, to raise one twin in a strictly controlled and sealed environment.

Why this matters so much is of course to do with humanity’s perception of its own potential for a better world. If men were really savage rapists held under control only by the repressive laws of a coercive hierarchical state, one could hardly expect women to support the socialist case for abolishing such coercive machinery. Similarly, if warlike aggression is built into us, as some anthropologists have claimed, the case for cooperation and common ownership suffers a major and possibly fatal reverse.

Some paleoanthropologists, and many Marxists, take the view that war did not exist before the development of agriculture, because the conditions giving rise to war did not exist. It is true to say that there is no hard evidence of war before settled communities began to defend their land from predation, but as Carl Sagan was fond of saying, absence of evidence is not evidence of absence. We are not able to point with certainty to 200,000 years of harmonious and peaceful human behaviour and say ‘there, that is our real nature.’ We can only look at this vast period of human activity, twenty times longer than all of recorded history, and say ‘they had no landed property, so it’s hard to see what they could have found to fight about.’

In the Democratic Republic of Congo (DRC) democratic elections have recently drawn to a close an appalling civil war that claimed four million lives. Ironically, in the dense forest of DRC, new studies have emerged which have done something to swing the nature-nurture pendulum back in the direction of the nurturists. Chimpanzees, once the lovable rogues of Tarzan films, have lately been receiving a rather bad press, with documentaries concentrating on their brutal behaviour both within and between tribes, including rape, murder and cannibalism. A genetically very close relative and Congolese next-door neighbour is the Bonobo or pygmy chimp, and this primate has always been something of a curiosity. When chimp troops meet, we are told, war and murder are invariably the result. When bonobo troops meet, a love-fest takes place, with the females of one troop running off into the bushes with the males of the other. There is no male hierarchical organisation among bonobos, plenty of casual sex of both hetero and same-sex varieties, and if any male exhibits any rare violent behaviour this is swiftly stamped out by the combined females.

This startling difference in behaviour between the two primates has led some anthropologists to a depressing conclusion. Human females, argue Richard Wrangham and Dale Peterson in their book Demonic Males (Houghton Mifflin, 1997), need to emulate the bonobo and take a more active political role in order to offset the male killing instinct. This is Thomas Hobbes territory again, and the same assumptions about nasty and brutish male violence which the authors use to argue for greater female political participation can of course also be used to justify the continuation or even extension of state repression.

What was deemed peculiar about the bonobo was that they inhabited the same forest as chimpanzees, albeit in a naturally secluded area which arguably protected them from the nasty and brutish chimps. On the face of it, bonobos seemed to lead a peaceful and communally supportive lifestyle simply because they liked it that way. Now it turns out that not all jungles are equal, and food supply has a lot more to do with it than was previously thought. The bonobo habitat just so happens to contain all the right vegetable nutrients to allow them to live largely as vegetarians and spend very little effort acquiring food. Chimp forests conversely offer much leaner pickings, with low-nutrient vegetation, high tannin content which requires much peeling and shelling, and a competition over resources which necessitates the organisation of meat hunting and aggressive defence of territory. As New Scientist observes: “Put bluntly, bonobos are nice because the environment they live in is nice” (December 2, 06). Not all anthropologists agree, citing the fact that in identical captive environments, bonobos and chimps continue to exhibit different behaviour. Nonetheless, give them long enough, and behaviour is likely to change. It is well known that primates can learn new behaviour and pass it on to descendants, as in the famous case of the Japanese macaques, who all learned to wash potatoes in the sea after watching one juvenile female do it first. In a chimpanzee environment, bonobos would begin to exhibit chimpanzee behaviour, and vice-versa.

The emphasis on the division between the bonobo ‘good guys’ and the chimpanzee ‘bad guys’ does chimpanzees a disservice, however. Little attention has been focussed in the TV documentaries on the fact that supposedly ‘inevitable’ violent behaviour is uncommon among young chimps and even among adult chimps in other locations in the Congo. Indeed, studies undertaken by anthropologists at the University of Saint Andrews in Edinburgh show that, even without ecologically explicable circumstances, there is more variation in chimp behaviour, no less than 39 different cultural patterns, than in any other animal studied in Africa.

The debate about primate behaviour informs the debate about human behaviour, and is not likely to be settled just yet. But humans, in displaying the most amazing array of behaviour patterns found in nature, can take comfort from the fact that, whatever the genes say or don’t say, there is one talent we have developed to a greater degree than any other animal, and which opens the door to a new form of society. Primates can learn to be different, and none better than us.