Sex difference in travel is concentrated in adolescence and tracks reproductive interests.

Sexual selection theory suggests that the sex with a higher potential reproductive rate will compete more strongly for access to mates. Stronger intra-sexual competition for mates may explain why males travel more extensively than females in many terrestrial vertebrates. A male-bias in lifetime distance travelled is a purported human universal, although this claim is based primarily on anecdotes.

Husband's esteem predicts his mate retention tactics.

Men sometimes enact mate retention tactics to thwart a partner's infidelity or prevent their defection from the relationship. These tactics include low-risk acts that render the current relationship more attractive by bestowing benefits on the woman, as well as cost-inflicting acts that render defection from the relationship risky or dangerous for her. Previous research has linked men's mate retention behavior with men's mate value (value as a current or potential partner) using women's reports.

Risk of death or life-threatening injury for women with children not sired by the abuser.

Women who are abused by their male intimate partners incur many costs, ranging in severity from fleeting physical pain to death. Previous research has linked the presence of children sired by a woman's previous partner to increased risk of woman abuse and to increased risk of femicide. The current research extends this work by securing data from samples of 111 unabused women, 111 less severely abused women, 128 more severely abused women, and 26 victims of intimate partner femicide from the Chicago Women's Health Risk Study to document an ordinal trend in the risk of experiencing more severe forms of violence for women who have children in the household sired by a previous partner.

Individual differences in women's rape avoidance behaviors.

Rape can exact severe psychological, physical, and reproductive costs on women, and likely was a recurrent adaptive problem over human evolutionary history. Therefore, women may have evolved psychological mechanisms that motivate rape avoidance behaviors. Guided heuristically by an evolutionary perspective, we tested the hypothesis that women's rape avoidance behaviors would vary with several individual difference variables.

Mate attraction, retention and expulsion.

Sexual selection theory and parental investment theory have guided much of the evolutionary psychological research on human mating. Based on these theories, researchers have predicted and found sex differences in mating preferences and behaviors. Men generally prefer that their long-term partners are youthful and physically attractive.