Access Type

Open Access Dissertation

Date of Award

January 2020

Degree Type


Degree Name




First Advisor

Glenn E. Weisfeld


Testosterone has long been implicated as a neuroendocrinological mechanism in the expression of reproductive strategies. Humans the world over form and maintain pair-bonds suggesting that pair-bonds may serve to enhance reproductive fitness. However, infidelity is a perennial threat to these bonds. The data in humans suggests that testosterone is associated with mate-seeking but may be detrimental to relationship maintenance. However, past work has relied on correlational studies and additional findings from nonhuman animal models suggest that acute changes rather than baseline concentrations in testosterone may in fact protect extant pair-bonds. The present research sought to test the causal role of testosterone in both mate-seeking [single men] and relationship maintenance [paired men] behaviors and perception using a between subject, double blind, placebo treatment protocol. The study recruited 212 healthy men, roughly half of whom were in a committed relationship and half single. The participants were briefly exposed to an attractive female confederate during which time the participants’ verbal and non-verbal behavior was recorded. Results indicated that among single men, testosterone moderated the effects of several of the confederate’s proceptivity behaviors on men’s self-presentation, such that her affiliative behavior was positively correlated with the men’s self-presentation. These results were restricted to single men; testosterone did not alter men’s courtship behavior among paired men, suggesting that acute changes in testosterone may not serve as a relationship protection mechanism in men. Additionally, testosterone caused men, regardless of relationship status, to perceive the confederate’s self-presentation behavior as indicative of her sexual interest. The results provide the first causal evidence for testosterone as a mate-seeking mechanism in healthy adult men and provide an outline to the psychological pathways through which testosterone alters men’s mating psychologies.