Evolutionary accounts of human behavioural diversity

Human beings persist in an extraordinary range of ecological settings, in the process exhibiting enormous behavioural diversity, both within and between populations. People vary in their social, mating and parental behaviour and have diverse and elaborate beliefs, traditions, norms and institutions. The aim of this theme issue is to ask whether, and how, evolutionary theory can help us to understand this diversity. In this introductory article, we provide a background to the debate surrounding how best to understand behavioural diversity using evolutionary models of human behaviour. In particular, we examine how diversity has been viewed by the main subdisciplines within the human evolutionary behavioural sciences, focusing in particular on the human behavioural ecology, evolutionary psychology and cultural evolution approaches. In addition to differences in focus and methodology, these subdisciplines have traditionally varied in the emphasis placed on human universals, ecological factors and socially learned behaviour, and on how they have addressed the issue of genetic variation. We reaffirm that evolutionary theory provides an essential framework for understanding behavioural diversity within and between human populations, but argue that greater integration between the subfields is critical to developing a satisfactory understanding of diversity

Applying evolutionary theory to human behaviour: past differences and current debates

The aim of this paper is to provide non-specialist readers with an introduction to some current controversies surrounding the application of evolutionary theory to human behaviour at the intersection of biology, psychology and anthropology. We review the three major contemporary sub-fields; namely Human Behavioural Ecology, Evolutionary Psychology and Cultural Evolution, and we compare their views on maladaptive behaviour, the proximal mechanisms of cultural transmission, and the relationship between human cognition and culture. For example, we show that the sub-fields vary in the amount of maladaptive behaviour that is predicted to occur in modern environments; Human Behavioural Ecologists start with the expectation that behaviour will be optimal, while Evolutionary Psychologists emphasize cases of ‘mis-match’ between modern environments and domain-specific, evolved psychological mechanisms. Cultural Evolutionists argue that social learning processes are effective at providing solutions to novel problems and describe how relatively weak, general-purpose learning mechanisms, alongside accurate cultural transmission, can lead to the cumulative evolution of adaptive cultural complexity but also sometimes to maladaptative behaviour. We then describe how the sub-fields view cooperative behaviour between non-kin, as an example of where the differences between the sub-fields are relevant to the economics community, and we discuss the hypothesis that a history of inter-group competition can explain the evolution of non-kin cooperation. We conclude that a complete understanding of human behaviour requires insights from all three fields and that many scholars no longer view them as distinct