Lateralization of pectoral stridulation sound production in the channel catfish.

Sounds of the channel catfish Ictalurus punctatus were found to consist of a rapid series of pulses produced by rubbing a ridged process on the first pectoral spine against the rough surface of a groove in the pectoral girdle during fin abduction. Although sounds can be made with either fin, approximately half of the individuals exhibited a fin preference, and 90% of these preferred the right fin. Unlike examples of handedness in other invertebrates and fishes, this preference is not simply a matter of anatomical asymmetry, but as in humans, reflects a preference between two equally developed limbs.