Fig. 8. Correlation between downstroke deviation and rotational forces. (A) Time course of rotational velocities and (B) time course of rotational forces for a single individual, color-coded according to downstroke deviation. Data are shown over a normalized time axis for the downstroke and upstroke. The filled gray box indicates the ventral rotation, and the open gray box indicates the dorsal rotation. For the ventral rotation, the pre-reversal portion occurs at the end of the downstroke, and the post-reversal portion occurs at the beginning of the upstroke. (C–G) The following data are for the experimental population. Black circles indicate values for the individual shown in A and B. Correlation between downstroke deviation and (C) pre-reversal peak rotational force (R²=0.07), (D) pre-reversal total force peak (R²=0.20), (E) post-reversal normalized time delay of rotational force peak (R²=0.15), (F) post-reversal peak rotational force (R²=0.60) and (G) post-reversal total force peak (R²=0.31).