Figure 5

Kinematic analysis of sound production and feeding events in Stegastes rectifraenum . A) Representation of the mean kinematic patterns (±SD) observed in sound production (black triangle), biting filamentous algae (dark grey square) and biting fixed pieces of food (light grey circle). The kinematic patterns end at the time of the bite. Figures 1, 2 and 3 represent different phases: during phase 1, only the lower jaw is moving; phase 2 starts at the onset of the relative movement between the neurocranium and hyoid apparatus and finishes at the end of the aperture phase (maximum lower jaw depression); phase 3 represents the mouth closure period. A zoomed in portion is shown for the two latter phases, SD were withdrawn to allow a better visualization of the different patterns. B) Schematic illustration of the skull kinematics during the different phases (1, 2 and 3). The arrows indicate the movements observed during the corresponding phase. Bolder arrows indicate faster movements. The left cheek of the fish was withdrawn to allow an inner view in the buccal cavity. The nasal and the infraorbital series bones were also removed, to have a better view of the upper oral jaw. The protraction movement of the upper jaws is not illustrated. NCR: neurocranium; PG: pectoral girdle; OS: opercular series; SP: suspensorium; HA: Hyoid apparatus; OJ: oral jaws, the c-md ligament is in black. C) Representation of the mean kinematic pattern (±SD) for biting fixed pieces of food while the c-md ligament is ablated. The kinematic pattern ends at the time of the bite.