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The evolution of altruism

Animal altruism

The primatologist and zoologist Frans de Waal highlights two propensities necessary for moral behaviour:

  1. Reciprocity with a sense of justice

    This is the practice of exchanging things with others for mutual benefit in a way that both parties feel is fair.

  2. Empathy and its related feeling of compassion

    This is the ability to recognise or share the feelings of others, to imaginatively identify with them and feel concern for their suffering.

Many animals are capable of displaying both. It is not only human beings, therefore, that appear to worry about the welfare of others. We see such behavior across the animal kingdom, but perhaps most strongly in those animals most closely related to us.

It is because we have the capacity for empathy with others that questions of morality arise. Without this propensity, it is difficult to imagine how we could ever have developed a morality anything like that which we see today. There is more to morality than empathy, but empathy gets morality off the ground.

‘All men have a mind which cannot bear to see the sufferings of others… When men suddenly see a child about to fall into a well, they will all experience a feeling of alarm and distress… to be without this distress is not human … Since we all have [this principle and others] in ourselves…Let them have their full development, and they will suffice to love and protect all [within] the four seas…’

Meng Tzu, The Works of Meng Tzu

How did this propensity to support others ever evolve? If our own survival is essential for us to pass on our genes, how did the genes that drive altruistic behaviour – and thus benefit others at our own expense – ever survive in the gene pool?

One explanation comes from the genetic benefits of kin altruism. This is the affection and support, common amongst mammals, that is shown towards close relatives. We share around 50% of our genes with our parents and children, and, on average, about 50% with our siblings. Altruistic behaviour towards our family can therefore support the survival of our genes. It is possible to appreciate how once we have such instincts for care and concern, they might then spread out more widely to other members of our species.

A second explanation lies in reciprocal altruism; acting in a way that is of a cost to oneself but benefits another, with the expectation that the favour will be returned.

‘It is surprising how many features of human ethics could have grown out of simple reciprocal practices like the mutual removal of parasites from awkward places that one cannot oneself reach.’

Peter Singer, The Expanding Circle

If such behaviour were to improve our own chances of survival and reproduction, then the genes that promoted such behaviour would be likely to spread. Of course, some may be tempted to cheat, and those that could cheat successfully would be more likely to benefit and pass on their genes. However, if one belongs to a species that can remember those who cheat, and can communicate this information to others, then the cheaters are unlikely to prosper for long.

Humans are social animals

Human beings, like many other mammals, are animals with evolved patterns of behaviour conducive to survival. Much of our behaviour is instinctive and universal. But the important thing is that we are social animals. Our pro-social behaviour has evolved alongside us, through both our biological and social history. Self-interest and survival instincts may provide the origins of our behavior, but, as we have seen, genetic influences mean we have good reasons to treat others well, and not only our immediate family. Our genes may be selfish but that does not mean we must be.

The evolutionary human success story is in part due to our ability to work together, to divide our labour, and to cooperate. These have enabled human societies to thrive. Without the natural capacity for empathy and a sense of fairness, would we have been able to build our civilisation? As we will see, our morality and the society in which we live has not been built on our natural instincts alone. But, for humanists, there is good reason to believe that in them lie the origins of our morality. They make morality possible. Our moral capacities do not need some other, non-natural explanation.

‘Ethics loses its air of mystery. Its principles are not laws written up in heaven. Nor are they absolute truths about the universe, know by intuition. The principles of ethics come from our own nature as social, reasoning beings.’

Peter Singer, The Expanding Circle

Question: Do you find the humanist explanation for the origins of our morality convincing?

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This article is from the free online course:

Introducing Humanism: Non-religious Approaches to Life

Humanists UK

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