Clarifying the Size-Frequency Relationship in Clownfish Acoustic Signals

Body size is the principal determinant of acoustic variation in anemonefish, reflecting both the mechanics of sound production and the size-based structure of their social hierarchies. In Amphiprion percula, the absence of a reported size-frequency relationship has led to the interpretation that small acoustic differences are rank-specific. We show that this outcome stems from analytical choices that obscure natural size variation, including pooling individuals across groups and removing size-rank covariance. Because behavioural categories correspond to distinct size classes, morphology must be explicitly accounted for.