Fig. 5

Operculum movements are coordinated with pectoral fin movements at both 3 and 5 days postfertilization (dpf). (a) At 3 dpf, all subjects (n = 9) produced bouts of high-frequency (10–35 Hz) pectoral fin movements, typically accompanied by one or more operculum movements. (b) At 5 dpf, all subjects (n = 8) produced shorter bouts of high-frequency (10–50 Hz) pectoral fin movements, almost always accompanied by one or more operculum movements. Operculum movements rarely occurred in the absence of pectoral fin movement, at either age. In both panels (a) and (b), a lateral view microscopic image of the subject is shown in the upper left, accompanied by a line drawing that highlights key anatomical features used to track fin and operculum movements. The plots underneath the images show the peak displacement times for the operculum and pectoral fin during a 30-s period, represented as vertical lines.