Our Closest Relatives: Bonobos, Chimps & Humans

international | sci-tech | opinion/analysis

Friday July 28, 2006 22:35

by James O'Brien

Review of "Our Inner Ape" by Frans de Waal

I picked up Frans de Waal’s latest offering as I’m interested in human evolution and a book which promised to discuss the behaviour of the common chimpanzee, its sister species the bonobo, together with humans promises insights into the biological underpinnings of empathy, aggression, sexuality and the like.

Panzee (Chimp) & Panbanisha (Bonobo)

If a behaviour is clearly common to all three species then there is a case that it goes back at least to a common ancestor, which would be around 6 million years ago. Alternatively it could simply be a “good trick” which our type of species, namely a sociable intelligent one, is likely to rediscover simply because evolution will select for it. An example of the latter is the eye, which has been invented many times completely independently. In principle there is no reason why the same couldn’t occur for behaviour.

The book is written in a very readable style, with its most notable feature being the stream of stories that the author recounts concerning the apes he knows.

The Bonobos
One of the last of the large mammals discovered by science also happens to be humanity’s joint closest relative. The bonobo, sister species to the more well known common chimpanzee, was only recognised as a distinct species in 1929. They are still relatively unknown and with an estimated population of only 20,000 left in the wild, plus a couple of hundred in captivity, their long-term existence is under serious threat. Continual human encroachment on their habitats by loggers in the Congo is severely undermining their long-term prospects.

Female Power
Bonobos are a female-centred, egalitarian primate species that largely substitute sex for the aggression. As de Waal is at pains to point out, this doesn’t mean they don’t have rows but that they are pretty good at making up afterwards. By contrast, male common chimpanzees, expend a lot of energy on intimidating rivals in order to secure maximum access to sexually available females. They also display an adeptness at Machiavellian intrigue. As no single chimpanzee is strong enough to become the alpha male on his own, he needs allies to support him against other rivals. But then, his allies are careful to cash in on the relationship by making more sexual advances to females even when in open sight of the alpha. An alpha male that is unable to retain the support of his allies is doomed to fall.

Bonobos are famous for their sexual behaviour. Sex is used not just as means of reproducing or as humans do to cement a pair-bond but as a casual way to ease social interactions. Both homosexual and heterosexual encounters are common. Females are particularly noted for their liaisons and this is a factor in the female dominance in bonobo society. Unlike the chimps where the aggressive males tend to dominate, females are top of the pecking order in bonobo society. When arriving at a new food source, females get first pickings even if it was a male who found the food first. And of course, before the food is eaten they have lots of sex to celebrate and presumably to cement social relationships. De Waal sums up the differences between them: “chimpanzees resolve sex issues through power; bonobos resolve power issues through sex”.

Chimpanzee Politics
De Waal dips into an earlier book of his, Chimpanzee Politics, which chronicles the rise and fall of the contending male chimps, Luit, Nikkie and the old fox Yeroen. The outcome is tragic, with one of the chimps eventually being killed by his rivals For those who pay attention to national politics or who have the misfortune to be a witness to office politics, the similarities are unmistakable. The chimps make deals, back out of them, are caught out and shamed, and so on.

Those of us on the left, especially the anarchists, may wish politics was more about ideas, issues and struggles, but unfortunately politics are put through the personality blender so that they are often so closely associated with individuals that loyalties are induced which run against people’s own better interests. This is one reason why, despite people being really dissatisfied over health care, stealth taxes, and the militarization of Shannon, the same old politicians get voted in. The system is constructed to foster personality politics, and perhaps this is a good fit with people’s interest in “people news” – gossip - rather than abstract ideas.

Brain Power
In order for the chimps to be able to operate a high level of political intrigue they need to have a brain powerful enough to make the calculations of who is friends with whom, what favours have been dispensed, the effect of one’s actions and so on. They also need a means of communicating fairly complex social information. De Waal says “it’s impossible to follow what’s going on in chimp community without distinguishing between the actors and trying to understand their goals. Chimpanzee politics, like human politics, is a matter of individual strategies clashing to see who comes out ahead.”

Being able to read the intentions of others is thought to be factor in the evolution of consciousness and intelligence. There is a selective advantage in being able to model the minds of others when you’re living in a large social group. And to do that you have to be able to imagine them as being a conscious individual. There is evidence that apes think about the consequences of their action and they are practiced at the art of deception. And in order to deceive somebody you have to be able to imagine what they will be thinking.

Although, the book emphasizes the considerable intelligence of Bonobos and chimps, de Waal doesn’t go into the intellectual achievements of two of the most famous Bonobos. Kanzi and Panbanisha. In a sense, it’s as if he’s confident that he can convince readers that apes are highly intelligent animals without discussing Kanzi whose accomplishments are the icing on the cake (see comments section).

Social Hierarchy
De Waal considers social hierarchy to be both a source of conflict and a source of stability. Chimpanzees and, to a much lesser extent, Bonobos, have hierarchical societies where there are top males and females. The ultimate reward is that those at the top get priority mating rights, so naturally they get to conceive more baby chimps. And naturally, the characteristics that got them to the top of the pecking order are passed on to the next generation.

The hierarchy provides stability because when it is clear what it is there is little conflict: “the hierarchical structure itself, once established, eliminates the need for further conflict”. Everybody can get on with the rest of their lives. However, when the existing order is challenged there is a lot of tension within the group and the playful behaviour gets replaced by attending to the serious business.

As there is an innate drive to attain high status, it is inevitable that the order will be challenged sooner or later. As a chimp is unable to rule by brute force – though it’s an essential component – the alpha male must be accepted by a majority of the group. Evolution will therefore have selected for the ability to interact well with one’s fellow chimps. If the top chimps begin to act against the wishes of a majority, then he could well find his position under threat.

De Waal posits similarities in this regard with human societies, most of which have a leadership of some sort, but, in the west at least, where the population have a degree of control over them. “Democracy”, he says, “elegantly satisfies two human tendencies at once: the will to power and the desire to hold it in check.” He agrees with Machiavelli that “one is better off becoming Prince with the support of the common people than with the help of the nobility, because the latter feel themselves so close to your position that they will try to undermine it. And the broader your power base, the better. This is good advice for chimps, too: males who stand up for the oppressed are the most loved and respected. Support from below stabilizes the top”.

But even apart from the arena of power politics, he argues that the social hierarchy is pervasive and not always in ways that the formal structure would lead us to believe. De Waal says that even humans who believe we are more egalitarian than chimps will have “to admit that our societies could not possibly function without an acknowledged order. We crave hierarchical transparency. Imagine the misunderstandings we would run into if people never gave us the slightest clue about their position in relation to us, whether in terms of appearance or in how they introduce themselves. Parents would walk into their child’s school and might just as easily be talking with the janitor as the principal. We would be forced to continually probe others while hoping not to offend the wrong person.”

Social Solidarity
In capitalist society, there is a premium on being able to out-compete all comers. But no society could survive without daily doses of cooperation and solidarity. These are often unremarked upon simply because they’re so natural. And for apes it is no different. “In a study in the Ivory Coast, chimpanzees took care of group mates wounded by leopards, licking away their blood, carefully removing dirt and preventing flies from coming near the wounds…All of this makes perfect sense given that chimpanzees live in groups for a reason, the same way wolves and people are group-animals for a reason. We would not be where we are today had our ancestors been socially adept.”

One of the foundation stones for social solidarity is the ability of apes to empathise. De Waal defines empathy as the ability to imagine yourself having somebody else’s experiences. There are many good anecdotes supporting the case that the higher primates do exactly that, and not just towards members of their own species. One bonobo guarded an injured bird until it recovered while a bonobo with heart trouble was well supported by his group.

De Waal considers reconciliation particularly important as it provides a way of managing aggressive behaviour. He argues that empathy is ingrained in apes – including us – and even rats and monkeys. “In classic experiments [which de Waal considers unethical]…one monkey stopped responding for five days and another one for twelve days after witnessing a companion being shocked each time they pulled a handle to get food themselves. These monkeys were literally starving themselves to avoid inflicting pain on others.”

The Bipolar Ape
De Waal’s thesis is that humans share the most notable characteristics of both the Bonobos and the Chimpanzees. On the one hand we have a tremendous capacity for violence, on the other we are incredibly sociable that we can live in cities with millions of people. And he canvasses for the theory that humans are simply apes who mature at much slower rate than other chimps, with whom we share over 95% of our dna. Human adults look like young apes and we have carried the inventiveness and curiosity of young mammals into adulthood.

Humans have undoubtedly attained such power that our decisions affect not only us, but the environment and pretty much all its species. As a consequence species like the bonobo are under threat of extinction. When humanity was perceived as being quite distinct from other animals this behaviour was understandable. We know now, however, from both genetics and evolution that this isn’t true. We are in the same boat as every species, even if we are steering it.

Video clips of bonobos, including ones of Kanzi making a stone tool and comprehending spoken English. http://www.greatapetrust.org/media/video-bonobo-kanzi.php#

BBC radio documentary on Kanzi and Sue Savage Rumbaugh http://www.bbc.co.uk/radio4/science/lifewithkanzi.shtml

The Great Ape Trust in the US of A, where Kanzi lives: http://www.greatapetrust.org/

Primates at Dublin Zoo: http://www.dublinzoo.ie/come_primates.htm

Bonobo photos by Frans de Waal