Fig. 5. Comparison of timing (A) and magnitude (B) of the observed and calculated forces exerted by bluegill on tethered prey. Time 0 (in B) is the first frame digitized in the image sequence (10 frames prior to the onset of gape, arbitrarily selected for each sequence). The timing differences between the observed and calculated peak force were not significantly different than 0 (average 2.2±0.83 ms; RM-ANOVA F_1,3=3.76, P>0.15) and were linearly correlated (average R²=0.78±0.06; average slope=0.89±0.09; N=4 fish). Similarly, the peak calculated force was not significantly different than the observed one (average deviation=–0.012±0.135 N; RM-ANOVA F_1,3=0.45, P>0.54) and the two magnitudes were correlated (average R²=0.59±0.07; average slope=0.78±0.1; N=4 fish). Different symbols represent data for the four fish studied, diagonal line represents the case of X=Y.