Fig. 8. Sound oscillograms and wing movements as recorded with the optical position detector. (A) Five consecutive songs (black) with their corresponding wing position trace (red); scale bar, 0.5 s. (B) Enlargement of one pulse of the sequence shown in A; scale bar, 20 ms. (C) Further enlargement of a segment of the pulse shown in B. Ripples in the wing position trace match sound waves; scale bar, 1 ms. (D) Velocity of wing closing, calculated from frame-by-frame analysis of high-speed video. Results for one song from each of four individuals are shown (symbols) along with a Lowess curve fit to the data (blue). (E) Velocity of wing closing, calculated from the wing movement trace of the position detector. Wing velocity traces for four songs from the same specimen are plotted (black) and line fitted to the average using the Lowess curve fit (blue).