In The Descent of Man, Darwin wrote: “of all the differences between man and the lower animals, the moral sense or conscience is by far the most important.” Since Darwin’s time, researchers have been looking into the possible origins of our morality do determine whether it is a trait that evolved—and if so, how and why.

Darwin was puzzled by the fact that human beings voluntarily go to war and die for their larger groups, as this doesn’t fit with the idea of natural selection being driven by individuals acting on their own self-interest. He proposed the idea of group selection, according to which a group with more altruists would have more survivors in a war or crisis, thereby passing on the altruistic genes. But the frequency of such events and the force of group selection would have to be enormous for it to override selection between individuals, making this theory unlikely.

Evolutionary anthropologist Christopher Boehm argues that human morality emerged when hunter-gatherers formed groups to hunt big game (about a quarter of a million years ago), and cooperation became necessary for survival. In this type of society where the food source has to be actively shared, alpha male tendencies would have been suppressed and hierarchies eliminated in order to share food evenly. Those who tried to take more than their fair share of meat would have been killed, and hence self-control and the willingness to share would have become evolutionarily successful traits.   

Michael Tomasello, co-director of the Max Planck Institute for Evolutionary Anthropology in Leipzig, has spent years conducting experiments on chimpanzees and human children to compare their social behaviour and cognitive abilities. He argues that human morality is a consequence of our tendency to collaborate more than other apes do. Chimpanzees may be said to have a social nature, with individuals sometimes working together; but according to Tomasello, only humans are “ultra-social”, having developed an enhanced predisposition to cooperation. This is borne out by experiments which shows that human toddlers are much more likely to choose cooperation than chimpanzees and are more willing to share rewards. Like Boehm, Tomasello subscribes to the collaborative hunting theory, but adds that this new food source not only encouraged sharing but led people to view themselves as part of a larger unit—a perspective which he calls “shared intentionality”, and which is behind all human collective projects and cultural institutions. This perspective, he believes, is the root of morality.

Applicants for Anthropology or Biology might want to familiarise themselves with Darwin’s thoughts on social evolution including the evolution of morality, and the subsequent research on it. Do you find the collaborative hunting theory convincing? Students wishing to study Theology or Philosophy may wish to think about the implications of these theories on our understanding of ethics more generally. If altruism is merely the result of certain genetic traits resulting in reproductive success for the individuals possessing them a specific context, is it objectively and universally required of us? In our current society, is altruism still an evolutionarily strong trait or do the ruthless come out on top?

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