ABSTRACT. In the United States, women have long held the right to vote and can participate fully in the political process, and yet they are underrepresented at all levels of elected office. Worldwide, men's dominance in the realm of politics has also been the norm. To date, scholars have focused on supply-side and demand-side explanations of women's underrepresentation but differences in how men and women assess electoral risk (the risk involved in seeking political office) are not fully explained. To fill this gap, I explore how evolutionary theory offers insights into gendered differences in political ambition and the evaluation of electoral risk. Using the framework of life-history theory, I hypothesize that both cognitive and environmental factors in human evolution, particularly as they relate to sexual selection and social roles, have shaped the psychology of ambition in gendered ways affecting contemporary politics. Cognitive risk-assessment mechanisms evolving in the hominid line came to be expressed differently in females and males, in women and men. These gendered expressions plausibly reflect differentiable environmental pressures in the past and may help explain behaviors in and barriers to women's electoral political activity in the present. If so, then the success of efforts to increase such activity -or, regressively, to suppress it -may be better understood.Key words: Political ambition, gender differences, evolutionary theory, electoral risk assessment M ale officeholders are the norm in political representation both worldwide and in the United States in particular. Across the globe, gender parity in political representation is unusual, and instances of women's overrepresentation are extremely rare. 1 In the United States, women make up slightly more than half of the population and earned the right to vote and participate fully in the political process many decades ago. Nevertheless, in recent U.S. history, less than a quarter of state legislators have been women; women have held few state executive offices; and women have comprised less than 20 percent of the membership of the U.S. Congress. 2 Proponents of greater gender equality in U.S. political representation continue to wonder why more women do not run for or hold political office when so many of the societal and structural barriers to their participation have diminished. The leading explanations tend to focus on candidate emergence and cultural doi: 10.1017/pls.2016.13Correspondence: Jennie Sweet-Cushman, Department of History, Political Science, and International Studies, Chatham University, 0 Woodland Road, Pittsburgh, PA 15232. Email: jsweetcushman@chatham.edu and psychological factors that contribute to men and women having different levels of political ambition. 3,4 However, these theories do not address what I consider to be critical questions: What role does electoral risk play in political ambition, and can evolutionary theory provide insight into gendered differences in risk assessment and political ambition? I argue that the ...