DETROIT - Theories have long proposed that testosterone influences competition among males trying to attract females. Findings from a recent study at Wayne State University give a clearer understanding of the links between testosterone and human mating behavior, and how testosterone is associated with dominance and competitive success when men battle for the attention of an attractive woman.

Richard Slatcher

The study engaged pairs of men in a seven-minute videotaped competition for the attention of an attractive female undergraduate. Pre-competition testosterone levels were positively associated with men's dominance behaviors in the mate competition-including how assertive they were and how much they "took control" of the conversation-and with how much the woman indicated that she "clicked" with each of the men.

According to Richard Slatcher, Ph.D., assistant professor of psychology in WSU's College of Liberal Arts and Sciences and a resident of Birmingham, Mich., the effects of testosterone on dominance behaviors were especially pronounced among men who reported having a high need for social dominance. In his study, "Testosterone and Self-Reported Dominance Interact to Influence Human Mating Behavior," published online Feb. 28 in the journal, Social Psychological and Personality Science, these men showed a strong positive association between their own testosterone and their own dominance behaviors and, most surprisingly, a strong negative association between their own testosterone and their opponents' dominance behaviors. In other words, men both high in testosterone and who reported a high need for social dominance appeared to be able somehow suppress their competitors' ability to attract potential mates. However, when men reported low need for dominance, there was no association between testosterone and dominance behaviors-either their own or their competitors'.

"We found that testosterone levels influenced men's dominance behaviors during the competitions, how much they derogated (or ‘bashed') their competitors afterward, and how much the woman said she ‘clicked' with them," said Slatcher. "Books, film and television often portray men who are bold and self-assured with women as being high in testosterone. Our results suggest that there is a kernel of truth to this stereotype, that naturally circulating testosterone indeed is associated with men's behaviors when they try to woo women."

Although many animal studies have shown that testosterone is associated with dominance when males compete for mates, none-until now-have demonstrated this association in humans.

"These findings highlight an important difference between humans and animals," said Slatcher. "In humans-unlike animals-explicit, conscious motives can affect how a hormone such as testosterone shapes behavior. Our findings indicate that testosterone is associated with dominance behaviors and success when men compete for the attention of an attractive woman, particularly when men also have a strong conscious desire for social dominance."

To view the study, visit http://go.wayne.edu/slatcher-spps.

Wayne State University is one of the nation's pre-eminent public research universities in an urban setting. Through its multidisciplinary approach to research and education, and its ongoing collaboration with government, industry and other institutions, the university seeks to enhance economic growth and improve the quality of life in the city of Detroit, state of Michigan and throughout the world. For more information on research at Wayne State University, visit http://www.research.wayne.edu/.