Sex-Specific Responses to Social Calls Shape Foraging Decisions in a Nectar-Feeding Bat.

Foraging in social animals involves balancing the benefits of social information against the costs of competition. In nectarivorous bats, social vocalizations are commonly produced at feeding sites, yet it remains unclear whether males and females respond differently to such signals. We investigated this by testing how alert calls linked to aggressive interactions and benign social calls influence foraging choices in bats (Glossophaga mutica handleyi). Bats changed their flower choices in response to playbacks, revealing marked sex differences. Males avoided flowers paired with alert calls, whereas females preferred them. Conversely, males showed no response to benign calls, whereas females were consistently drawn to flowers paired with social calls regardless of call type. Acoustic analyses revealed no differences between male and female alert calls, suggesting that these sex-specific responses stem from receiver behavior rather than signal design. Furthermore, only dominant males approached flowers associated with alert calls, suggesting that competitive ability influences responses to conflict-related signals. Overall, these results demonstrate that the same social signal can trigger different behavioral strategies in male and female bats. Our study underscores the importance of receiver-dependent processes in shaping communication systems and shows that sex-specific responses to social signals can develop without sex-specific variation in signals.