Fig. 4. Evidence that fish initiate their rapid turn within approximately 100 ms and are aligned while the prey is still on its ballistic path. The time intervals from when the prey was dislodged until the initiation of a turning maneuver (open columns) and until turning was completed (filled columns) were sampled at 20 ms intervals and accumulated in histograms normalized so that the total frequency equalled 1. The results obtained at both prey heights h are shown and the time to prey hitting the water surface (i.e. (2h/g)^1/2, where g=9.81 m s^-2) is indicated by the dotted lines. (A) h=20 cm, N=60 responses; (B) h=40 cm, N=64 responses.