His research and writing integrate three scientific syntheses of the last few decades: evolutionary psychology, cognitive science, and dynamical systems theory.
Research he conducted with Richard C. Keefe overturned a long-standing assumption that women are attracted to older men, and vice versa, because of the norms of American society.
Research with Norman P. Li demonstrated that sex differences are more pronounced when men and women are given a realistic budget, and not asked simply to list their ideal desires in a mate.
Research conducted with Jon Maner, Steven Neuberg, Mark Schaller, and Vaughn Becker has focused on the implications of evolutionarily important motivational states on ongoing cognitive processes.
This research has demonstrated that people in a self-protective frame of mind are sensitized to potential threats from outgroup males, interpreting neutral facial expressions on such men as hiding anger, for example.
Research (conducted with Vladas Griskevicius, Robert Cialdini, Jill Sundie, Joshua Ackerman, Adam Cohen and other colleagues) has examined the effects of evolutionary significant motives for a number of complex social behaviors, including conformity, creative display, conspicuous consumption, aggression, and economic decision-making.