Fig. 9. Fast turn of zebrafish larvae. Age post-fertilisation: (A) 2 days; (B) 4 days; (C) 7 days; (D) 21 days. (i) Midlines of the larva in an earth frame of reference (time step 1 ms). Maximum translational speed: thin green midline; maximum acceleration: thick green midline. Scale bar, 0.5L. (ii) Profiles of specific curvature. Contours of the specific curvature of the midlines, plotted along the body axis (x-axis) and in time (y-axis) for one complete tail beat cycle.