Other women's fertility moderates female resource distribution across the menstrual cycle

Status competition among female mammals tends to intensify near ovulation. Females compete selectively, targeting females who most threaten their own likelihood of conception. The present study explored the extent to which regularly cycling women differentially compete with other women in a behavioral economic game as a function of both women's fertility. We find evidence for an interaction between participant and target fertility, such that women withhold more resources from another woman, thereby keeping more for themselves, when both women are in the fertile (late follicular) phase of their menstrual cycle. Results expand research on women's perceptions of fertility cues in other women by demonstrating a possible role for such cues in modulating female social behavior.