In theory, observed correlations between genetic information and behaviour might be useful to members of the WEIRD (western, educated, industrialized, rich, and democratic) populations. Guiding young people to choose educational opportunities that best match their abilities would benefit both the individual and society. In practice, however, such choices are far more profoundly limited by the culture people have inherited than their genes.
View Article and Find Full Text PDFThe main objective of our target article was to sketch the empirical case for the importance of selection at the level of groups on cultural variation. Such variation is massive in humans, but modest or absent in other species. Group selection processes acting on this variation is a framework for developing explanations of the unusual level of cooperation between non-relatives found in our species.
View Article and Find Full Text PDFHuman cooperation is highly unusual. We live in large groups composed mostly of non-relatives. Evolutionists have proposed a number of explanations for this pattern, including cultural group selection and extensions of more general processes such as reciprocity, kin selection, and multi-level selection acting on genes.
View Article and Find Full Text PDFDerived aspects of our human life history, such as short interbirth intervals and altricial newborns, have been attributed to male provisioning of nutrient-rich meat within monogamous relationships. However, many primatologists and anthropologists have questioned the relative importance of pair-bonding and biparental care, pointing to evidence that cooperative breeding better characterizes human reproductive and child-care relationships. We present a mathematical model with empirically-informed parameter ranges showing that natural selection favors cooperation among mothers over a wide range of conditions.
View Article and Find Full Text PDFCopying others appears to be a cost-effective way of obtaining adaptive information, particularly when flexibly employed. However, adult humans differ considerably in their propensity to use information from others, even when this 'social information' is beneficial, raising the possibility that stable individual differences constrain flexibility in social information use. We used two dissimilar decision-making computer games to investigate whether individuals flexibly adjusted their use of social information to current conditions or whether they valued social information similarly in both games.
View Article and Find Full Text PDFVerbal and mathematical models that consider the costs and benefits of behavioral strategies have been useful in explaining animal behavior and are often used as the basis of evolutionary explanations of human behavior. In most cases, however, these models do not account for the effects that group structure and cultural traditions within a human population have on the costs and benefits of its members' decisions. Nor do they consider the likelihood that cultural as well as genetic traits will be subject to natural selection.
View Article and Find Full Text PDFAm J Hum Biol
September 2009
Achievements that attract social rewards in developed countries, such as educational qualifications, a prestigious career, and the ability to acquire prestige goods, interfere with a woman's ability to achieve reproductive success. This tradeoff between cultural and reproductive success may have developed because economic development creates an evolutionarily novel social environment. In the social environment of developed countries, a far smaller proportion of social exchange is between kin than in the small-scale communities in which the human brain and behavior evolved.
View Article and Find Full Text PDFAs societies modernize, they go through what has become known as "the demographic transition;" couples begin to limit the size of their families. Models to explain this change assume that reproductive behavior is either under individual control or under social control. The evidence that social influence plays a role in the control of reproduction is strong, but the models cannot adequately explain why the development of small family norms always accompanies modernization.
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