Primate instincts

We learn to tell right from wrong as children, right? Wrong. Research on monkeys has shown that, even from birth, a sense of morality is programmed into our genetic code

Sarah and Django sat together as Sarah's baby Ricky climbed on Django's back. Django, a big male, soon wanted Ricky off. He began jumping about and pushing at Ricky until the baby fell to the ground. He was unhurt, but Sarah screamed at Django whenever he came near.

Sarah and Django sat together as Sarah's baby Ricky climbed on Django's back. Django, a big male, soon wanted Ricky off. He began jumping about and pushing at Ricky until the baby fell to the ground. He was unhurt, but Sarah screamed at Django whenever he came near.

Some time later a fight broke out, as Sarah's entire family joined in to attack Django, along with most of the females of the group. Django crept off while the group huddled together, embracing each other. Only Liz, an old but unrelated friend of Django's, went to him and groomed his cuts.

The characters in this vignette are woolly monkeys; grey, furry creatures living in a primate sanctuary in Cornwall, where I worked as a keeper some years ago. Do their actions here describe a species devoid of ethics? It seems unlikely that they have a concept of "moral" behaviour, but their actions do appear to indicate the existence of social rules and real concern for others.

This notion is not in keeping, at least at first sight, with the prevailing view of evolutionary biologists: that morality is a human quality produced only by fighting against our natural instincts. Richard Dawkins, the Charles Simonyi Professor of the Public Understanding of Science at Oxford University, said in the last sentence of his seminal work The Selfish Gene : "We alone on earth can rebel against the tyranny of the selfish replicators." Dawkins is in good company; in the 19th century, Thomas Huxley - "Darwin's bulldog" - insisted that morality was a departure from nature, uniquely human and calculated.

In a recent lecture, however, Frans de Waal, the CH Candler Professor of Primate Behavior at Emory University in Atlanta, challenged this idea. "How can you overcome your own nature, with your own nature?" he asked.

De Waal proposes that we, as moral animals, evolved through natural selection on social processes. In other words, it is of benefit to us as individuals to behave morally and to promote a society based on morally enforced rules. De Waal cites studies of non-human primates, which appear to show continuity between humans and other primates in moral behaviour. "I'm not suggesting that apes are moral beings," he says, "but that they have at least the building blocks of moral behaviour."

To have morality, we need to be aware of the feelings of others. Evidence is accruing for empathy and, in some cases, sympathy in monkeys and apes. Chimpanzees console one another; if one is distressed, another provides reassurance, usually with an embrace in a way reminiscent of a human mother comforting her child.

That apes are able to understand the needs of others and respond to them is illustrated in a recent incident at Brooklyn Zoo. When a three-year-old boy lay unconscious after falling six metres into the gorilla enclosure, a female gorilla picked him up and patted him on the back. She then dragged the boy over to an area where the keepers would be able to get him. "This behaviour is simply an extension of what they would do within their own species," De Waal says.

Another building block of a moral society has to be an ability to reconcile after conflicts. Woolly monkeys make up by "snuffling", where they cover their mouths with a hand and puff their cheeks. Bonobos do it with sex. Domestic goats reconcile: so do dolphins, hyenas and other animals. But not domestic cats. "Domestic cats are solitary hunters," De Waal says, "so they don't need to maintain nice relationships with potential competitors. They do not live in the give-and-take society of primates, or social cats such as lions."

Humans have myriad techniques for reconciling after a fight, be it a box of chocolates, a hug or an international treaty. But the most important issue in all this is the worth of relationships. "We are learning that primates, including humans, suppress aggression or make peace not for peace's sake but in order to preserve something valuable," De Waal says.

After the Second World War, the establishment of the European Union was designed to increase the stake countries had in each other, so discouraging conflict. The same effect can be seen in non-human primate societies, where increasing the value of relationships can promote more peaceful interaction. Marina Cords and Sylvie Thurnheer demonstrated this elegantly with an experiment on long-tailed macaques at the University of Zürich. They found that pairs of monkeys who had learnt to co-operate with each other to get food rewards reconciled after quarrels far more readily than those who didn't need to co-operate.

To live by a moral code, there needs to be give and take. Monkeys and apes trade a variety of currencies, including grooming, support in fights, feeding space and so on. De Waal has shown that prior grooming increases the likelihood of food-sharing in chimpanzees, and that capuchin monkeys tend to share with those who have already shared with them.

But Nicola Koyama and her colleagues at Liverpool John Moores University and Chester Zoo have gone a step further in soon-to-be published research on captive chimpanzees. Koyama found that if chimp A groomed chimp B, then B would be more likely to support A in a fight with others the next day. The interesting part is that this only holds true if chimp A was the one who was going to start the fight. It appears that chimps are able to anticipate conflict and the need for support, and garner favours accordingly.

Richard Dawkins agrees that natural selection is ultimately responsible for the way humans behave, but says a feature that sets us apart is the fact that we have evolved the cognitive machinery to look much further into the future and see the consequences of our actions. "The proximate foresight of our ape ancestors has evolved into a much longer-term foresight," he says. "We know we want to live in the kind of society where we can be happy, so we behave in a way that might be immediately costly in order to achieve that."

Does this phenomenon exist, albeit at a far more primitive level, in monkeys and apes? In a famous experiment by Sarah Brosnan and De Waal, capuchin monkeys rejected cucumber, a favoured food, when they saw a cage-mate being given a highly prized grape. The hard-done-by capuchin would throw a tantrum or sulk; actions reminiscent of a child who has been treated unfairly. "Such behaviour seems irrational at an individual level," De Waal says. "Why waste good food? But it makes sense in the long run as it helps to maintain fair play."

For social rules to work and individuals to conform, the costs of cheating must be high. The woolly monkey Django suffered for his faux pas with the infant Ricky. A more severe example of punishment occurred in a wild chimpanzee community at Gombe in Tanzania. When Goblin, a bullying alpha male, was challenged by another male, the entire group joined in a ferocious near-fatal attack on him.

So, in the long run, it pays to behave yourself. But how can we account for the true altruism humans display in, say, donating anonymously to Oxfam? Dawkins says we can explain this seemingly illogical human behaviour through evolutionary rules of thumb. "We evolved in family groups on the savannah, where we came into contact with the same people again and again, and they were likely to be close kin. These are conditions where altruistic behaviour would be favoured by natural selection," he says.

"The best way to behave, then, is, 'Be nice to everyone you meet,' but this rule no longer applies in a modern city environment where we regularly mix with strangers. We have evolved the psychological mechanisms of empathy and sympathy, but they are now misfiring from the point of view of our selfish genes."

Whether you are a conscious being displaying great foresight, or just a creature who needs support to get access to food, social animals need to live in a social world to survive. We have evolved to play by the social rules.