Sociosexual Norms, The Behavioural Immune System Hypothesis And The Red Queen

Abstract

Pathogen pressure has played an extremely influential role in human adaptive evolution. It is well established that this role includes extensive selective sweeps upon the genetic substrates of antibody repertoires. A growing volume of research suggests that this role may extend to the evolution of sophisticated cognitive mechanisms via which individuals detect and avoid initial infection. In humans, such mechanisms may play an influential role in the emergence, establishment and reinforcement of cultural norms of behaviour. This is termed the behavioural immune system hypothesis. Sexual behaviour, which represents a significant potential route to infection, is the subject of widely differing attitudes and norms throughout the world. Herein, it is hypothesised that norms of restrictiveness may tend to vary along gradients of pathogen prevalence. It is further hypothesised that differential fitness costs between the sexes, arising from pathogen stress, may contribute towards explaining the existence of differing levels of sexual permissiveness. To account for the contingency that the results yielded track in the opposite to that which is hypothesised, the Red Queen hypothesis (wherein the faster adaptive rate of pathogens predicts a preference for genetic diversity – and thus less restrictive social norms) is put forth as a counterpoint. Improved characterisation of the biocultural basis of differing sexual norms promises to provide insights useful in anthropological research, as well as public health planning and risk mitigation. Show more