A kinematic analysis of evasive dodging movements used during food protection in the rat (Rattus norvegicus): Evidence for sex differences in movement.

Food-deprived rats (Rattus norvegicus) will protect their food by dodging away from a conspecific. A detailed kinematic analysis of these movements in adult rats shows that each sex uses sex-typical movements. Females move their snout through a greater spatial curvature, and their snout achieves a greater velocity, relative to the pelvis, than males. Males make more hindpaw steps than females and achieve a more simultaneous movement of the fore- and hindquarters. This suggests that females pivot around a point more posterior on the body than males. The finding that functionally similar patterns of movement have a sex-specific organization provides a new dimension for the study of sex differences. These differences are discussed in relation to sex differences in sex-typical behaviors, associated body structure, and neural control.