Social behavior of butterfly and surgeonfishes on coral reefs: Some mirror experiments.

Chaetodontids and acanthurids showed behavior that suggested the existence of dominance systems. There was no sign that the poster colors of chaetodontids serve as territorial signals, and there were interspecific differences in their responses to the mirror. Aggressive butterfly fishes usually butted with the spines of the forward part of the dorsal fin; surgeonfishes used their scalpels in attacks against their images.