Sex differences and contest experience shape walking patterns in the broad-horned flour beetle

Animal movement patterns vary widely across species, and sex differences are often expected because males typically need to encounter multiple females and acquire resources. In species where males engage in male–male combat using exaggerated weapons, variation in weapon size and contest outcomes is known to influence male reproductive strategies, and may therefore also affect movement behavior. However, sex-specific and male-specific differences in locomotor behavior, particularly in relation to weapon size and social interactions, remain poorly understood. Here, we investigated walking trajectories in the broad-horned flour beetle (Gnatocerus cornutus) to test for (1) sex differences, (2) associations between male weapon size and movement behavior, and (3) the effects of male–male combat. Males exhibited more tortuous and localized movement, whereas females showed straighter and more spatially extensive trajectories. Following contests, all males showed a reduction in activity regardless of contest outcome; however, winners and losers exhibited divergent changes in movement patterns, with winners showing straighter and more spatially extensive trajectories and losers showing more tortuous and localized trajectories. In contrast, body-size-corrected weapon size was not associated with any aspect of walking behavior. These results indicate that locomotor behavior in G. cornutus varies with sex and contest experience, and that variation in walking behavior is more closely associated with social experience than with weapon morphology.