The Social Instinct: How Cooperation Shaped the World

Nichola Raihani

My review 2022-11-04

This is one of the best books on human evolution I have read. Nichola Raihani writes very well, and manages to explain scientific results and theoretical arguments in a very accessible manner. Beginning with cooperation on the level of genes, she goes on to explain how cooperation is the basis for multicellular life, continuing to cooperation between individual organisms. As part of the package, we get a very good description of how evolution works in general.

What I like most about her account is the emphasis that evolution does not prescribe one single solution to the problem of life. The slogan "survival of the fittest" is often taken to imply that "fitness" is simple and straightforward, and can therefore be achieved in only one way. This is not so. There are many ways of living, many possible strategies, and the context, including ecology, climate, genetics, and simple randomness, affect the outcome. Connected to this is also the important point made by Raihani that if we want to understand human sociality, it is not self-evident that we should look at our closest evolutionary relatives, such as the great apes. Rather, we should look at other species whose ecological and genetic context is similar in relevant aspects. The meerkats or the naked mole-rats have more in common regarding certain aspects of their social lives with humans, in spite of their more distant evolutionary relationships.

An important theme in the latter part of the book, where Raihani discusses how evolution has formed Homo sapiens, is the notion of social dilemmas. We are a profoundly social species, but being social implies its own built-in contradictions, such as the Tragedy of the commons, where the use of a common resource needs to be carefully managed, but each individual has an incentive to use it to the fullest, thereby collectively overusing it. How this problem can be solved is an important research topic with Elinor Ostrom as a central figure. This work is discussed by Raihani in the context of the Covid-19 pandemic and the current climate crisis.

If there is one point of criticism, it would be her treatment of culture. The special role of cumulative culture, including norms, in human affairs is discussed by Raihani, but somehow I feel that she is not giving it the weight it should have in her discussion. Discussing hunter-gatherer societies, she seems to suggest that they were more similar than societies are today; this is, I think, wrong. Anthropological studies rather indicate the opposite. Hunter-gatherers were probably very culturally diverse. But this is a minor point in an otherwise highly readable book, which I would recommend to anyone interested in the subject.