Elizabeth Cashdan: University of Utah

Sex differences in range size and navigation are widely reported, with males traveling farther than females, being less spatially anxious, and, in many studies, navigating more effectively. We want to know why males range farther, and what this might tell us about sex differences in wayfinding and spatial confidence. Proposed evolutionary explanations have suggested that males gain mating benefits from large ranges (mating hypothesis), while females incur greater fitness costs from such travel due to parenting constraints (parenting hypothesis). We find support for both hypotheses, but a comparison of the polygynous Twe and the monogamous Maya suggests that the importance of the two hypotheses varies facultatively with mating patterns. Our work in Utah also indicates that women’s greater harm avoidance is a partial mediator of the sex difference in mobility, which in turn affects navigational style and ability.