Movie S2.

cwr1003; cwr1006 larvae at 27 dpf: Three larvae were placed in the Petri dish. The video starts with two larvae in focus (foreground). Two of these larvae (in focus) remained sedentary until disturbed by the tapping that started after ∼5 seconds (00:05). The swim bladders in these two larvae are visible and appear to be of normal size. The observed displacement of the Petri dish and its contents reflect (tapping) vibration traversing the medium. Two larvae responded by moving in short spurts, and in opposite directions. Several taps were required to move one larva (seen to the lower left of the screen) away from the field of view, while the other (seen on the lower right of the screen) was a bit more responsive. A third larva came into focus at ∼20 seconds (00:20), when the tapping was underway, and responded to the stimulus but displayed abnormal orientation while escaping – head down and tail perpendicular 7 to the base (at 21 seconds, 00:21). These phenotypes suggest variable, progressive loss of hair cell function in the cwr1003; cwr1006 line.