Figure 4. The effect of flight behavior of predatory hornets on the waving strength of Giant honeybees (scenario B).

The waving strength W₆₀₀ gives the numbers of bees which had shaken their abdomens over 15 frames (definition see inset and text); it depends on the hornet's distance from the nest d_xz (A) and on the hornet's flight velocity v_xz (B); time zero in the insets defines the start of the shimmering waves (cf. Fig. 3); (A,C) red to yellow shaded areas define the five d_xz classes, and (B,D) green to blue shaded areas define the eight v_xz classes of hornet flights as used in Fig. 3 (for definition see Methods); open circles are arithmetical means, thin vertical and horizontal lines denote SEM; thick lines are regressions of the mean values regarding to 201 wave episodes with 317 flight episodes of two wasps (Cd_xz = 1 to 5; Cv_xz = 1 to 8); regression A: r = −0.969, P = 0.006; regression B: r = −0.963, P = 0.015. W₋₄₀₀, the amplitude of the waving strength 400 ms before the onset of the consecutive wave (see inset and text for definition), giving the residual shimmering strength under repetitive conditions; W₋₄₀₀ declines with d_xz (regression C: r = −0.989; P = 0.022), but inclines regarding v_xz at lower velocity levels (Cv_xz = 1–5: regression d₁: r = 0.975, P = 0.005) and shows an overall nonlinear relation for Cv_xz = 1–8 (regression d₂: r = 0.857; P = 0.027). All tests refer to Polynomial Regression (SigmaStat).