Nonindependent mate choice in humans

Mate choice copying is the most studied type of nonindependent mate choice, i.e. mate choice that is influenced by the choices of other same-sex conspecifics (usually females). In copying, the probability of a male being chosen by a female ('focal' female) increases if he has previously been chosen by other females ('model' females) and decreases if he has been rejected. I critically review the non-human literature and conclude that from an evolutionary perspective copying is ill-suited to monogamous or relatively monogamous species like humans. I propose instead a related process where females are influenced not by a male‟s success at securing mates but by the quality of females that choose him. Although sometimes described as copying, this type of nonindependent mate choice is characterized by distinct evolutionary dynamics and ecological requirements, leads to different testable predictions and must therefore be urgently distinguished from mate choice copying. The term mate quality bias is suggested as an appropriate term for this phenomenon. I also report experimental studies that presented female raters with both static and video images of model females and their supposed partners. The two main findings to emerge from these experiments are a) the main - and perhaps the only - relevant cue in the model female is attractiveness and b) experimental studies can suffer from reduced external validity and need to be supplemented with non-experimental approaches. In line with this latter finding, I report one of the first non-experimental studies of nonindependent mate choice in humans. This involved the administration of a novel questionnaire to a large sample (n=401) of male and female undergraduates. The results of this study provide strong support support for nonindependent mate choice in humans a) being an empirical reality and b)influencing female, but not male choice. Finally, I report two experimental studies which examined how a man's partner influences male-male assessment and competition. The first used the dictator and ultimatum games to examine if offers made to male recipients were influenced by the attractiveness of the recipient‟s partner. The second used the Wason selection task to examine whether male subjects' cheater detection faculties are influenced by the attractiveness of the target male‟s partner (used here as a proxy for dominance). Although the results were generally in the expected direction, experimental manipulation of female partner attractiveness did not significantly affect male raters' perceptions of, and behaviour towards, the target male. The thesis concludes with a critical evaluation of the results obtained herein and suggestions for future research