The synergistic effect of prosociality and physical attractiveness on mate desirability.

Mate selection requires a prioritization and joint evaluation of different traits present or absent in potential mates. Herein, we focus on two such traits - physical attractiveness and prosociality - and examine how they jointly shape impressions of overall desirability. We report on two related experiments which make use of an innovative methodology combining large samples of raters and target persons (i.e., stimuli) and information on targets' behaviour in economic games representing altruistic behaviour (Experiment 1) and trustworthiness (Experiment 2), two important facets of prosociality. In accordance with predictions derived from a cognitive perspective on mate choice and sexual strategies theory, the results show that the impact of being prosocial on an individual's overall desirability was increased further by them also being physically attractive, but only in long-term mating contexts. Furthermore, we show that men's mate preferences for certain prosocial traits (i.e., trustworthiness) were more context-dependent than women's due to differential evolutionary pressures for ancestral men and women.