Fig. 2. Flies modulate wingbeat amplitude (WBA) in synchrony with oscillations in visual and mechanical roll. The sample responses of a single fly are shown. (A) Each trace represents the mean ± S.E.M. of 9 presentations of mechanical oscillations at the stated velocity. (B) Each trace represents the mean ± S.E.M. of 13 presentations of visual oscillations at the stated velocity. L, left; R, right. Scale bars represent 0.5 s and 0.5 V in relative WBA units.