Editorial overview: Evolutionary psychology

Functional approaches in psychology - which ask what behavior is good for - are almost as old as scientific psychology itself. Yet sophisticated, generative functional theories were not possible until developments in evolutionary biology in the mid-20th century. Arising in the last three decades, evolutionary psychology was inspired by these developments. This field cuts across traditional subdisciplines in psychology (e.g. social, cognitive, personality, developmental, abnormal psychology, and so on). As testified by the 23 papers in this issue, evolutionary psychology today thrives as a highly integrative, cross-disciplinary, generative approach to understanding human behavior

Major histocompatibility complex genes, symmetry, and body scent attractiveness in men and women

Previous research indicates that the scent of developmental stability (low fluctuating asymmetry, FA) is attractive to women who are fertile (at high-conception risk points in their menstrual cycles), but not to other women or men. Prior research also indicates that the scent of dissimilarity in major histocompatibility complex (MHC) genes may play a role in human mate choice. We studied the scent attractiveness to the opposite sex of t-shirts worn for 2 nights\u27 sleep. Our results indicate that the two olfactory systems are independent. We repeated previous results from studies of the scent of symmetry. We repeated previous results from MHC research in part; men, but not women, showed a preference for t-shirts with the scent of MHC dissimilarity. Women\u27s scent ratings of t-shirts were uncorrelated with the wearer\u27s MHC dissimilarity and allele frequency, but positively correlated with the wearer\u27s MHC heterozygosity. Fertile women did not exhibit any MHC trait preferences. Women\u27s preference for the scent of men who were heterozygous for MHC alleles may be stronger in women who are at infertile cycle points. Men preferred the scent of common MHC alleles, which may function to avoid mates with rare alleles that exhibit gestational drive. Men also preferred the scent of women at fertile cycle points. The scent of facially attractive women, but not men, was preferred. Neither FA nor facial attractiveness in either sex correlated with MHC dissimilarity to others, MHC heterozygosity, or MHC allelic rarity