In Does Altruism Exist? Culture, Genes, and the Welfare of Others, David Sloan Wilson sets out the evolutionary story. How we might have evolved to be self-sacrificing has long been a challenge for Darwinism — after all, those who give their lives to save their community do not pass on their genes. Even less extreme kindnesses such as sharing food with a sick friend could put someone at a disadvantage in the ruthless race to be the fittest.
Various theories have been put forward to solve this puzzle. Wilson, professor of biology and anthropology at the Binghamton University in New York State, has long been an advocate of one in particular called group selection. He claims that this view has now won out; a claim with which many biologists would disagree. But in this short and punchy book, he does an excellent job of explaining the relationship between the different theories and the now substantial evidence that we have indeed evolved to do each other good turns.
The essence of group selection is this: “although a high standard of morality gives but a slight or no advantage to each individual man and his children over other men of the same tribe . . . an increase in the number of well-endowed men and an advancement in the standard of morality will certainly give an immense advantage to one tribe over another. A tribe including many members who, from possessing a high degree of the spirit of patriotism, fidelity, obedience, courage, and sympathy were always ready to aid one another, and to sacrifice themselves for the common good, would be victorious over most other tribes, and this would be natural selection.”
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