Cuttlefish perform multiple agonistic displays to communicate a hierarchy of threats

摘要

Many animals perform multiple displays during fights, but the roles of these displays often remain ambiguous. The hierarchical signaling hypothesis posits that animals produce multiple displays to convey different levels of aggressive intent, allowing signalers to communicate graded series of threats. We tested this hypothesis in giant Australian cuttlefish, Sepia apama. Specifically, we tested whether (i) displays in early stages of a fight predict displays in later stages of a fight and (ii) displays produced in later stages of a fight provide reliable predictors of physical aggression. Our results support these predictions and reveal that fighting cuttlefish progress from low-risk signals to high-risk signals to convey a hierarchy of threats. This study highlights the generality of hierarchical signaling during animal contests, as cuttlefish are evolutionary far removed from many of the species that have been reported to use this type of signaling.