Fig. 7. Correlation between downstroke deviation and the mid-stroke angle of attack, tip velocity and translatory force for the experimental population. Black circles indicate values for the individual shown in Fig. 6. (A) Correlation between downstroke deviation and mid-downstroke angle of attack (R²=0.41), tip velocity (R²=0.22) and translatory force (R²=0.58). (B) Correlation between downstroke deviation and mid-upstroke angle of attack (R²=0.06), tip velocity (R²=0.05) and translatory force (R²=0.23). Five separate regressions are shown for five individuals.