Date of Award

Fall 2011

Degree Type


Degree Name

Doctor of Psychology (PsyD)




Tracy Vaillancourt




I examine female aggression as a competitive strategy for achieving reproductive success. In Chapter 1 an evolutionary theory of female aggression is presented. In Chapter 2 intrasexual competition for mates is considered by examining longitudinal links between aggression and dating behaviour among male and female adolescents. Results indicated that indirectly aggressive boys and girls were significantly more likely to have a dating partner at 1-year follow-up. Adolescents who reported being victimized by their peers were significantly less likely to have a dating partner at follow-up.

In Chapter 3 I examine female mate-guarding behaviour. Results demonstrated that aggression toward peers and partners was greater among heterosexual females who perceived intrasexual competitors as being more attractive than them. These links were mediated by romantic jealousy. Females perceiving themselves as more attractive than peers frequently reported being targets of females’ peer-aggression. The findings of chapters 2 and 3 suggest that females actively compete to attain and retain mates.

Chapter 4 examines implications for male victims of female aggression. We found that male victims of female partner violence were lower in testosterone than were non-victimized males. Participants held more negative attitudes toward male versus female victims. Males were less likely to seek-help and were more likely to minimize their perceived victimization. These findings suggest threats to male dominance and greater stigma likely reinforce males’ minimization and concealment of victimization.

This dissertation contributes to the field of aggression by empirically demonstrating evolutionary-based motives and functions of female aggression as a strategy for bolstering reproductive fitness.

McMaster University Library

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