Fig. 8. Pectoral fin contribution to turn direction. The difference between right and left pectoral fin velocities, after subtraction of the body velocity, is plotted against turn angle for each sequence measured. Points are coded according to fish fork length (see key). Left turn angles are coded as negative while right turn angles are coded as positive. During a turn in either direction there is no pattern of the same fin (left or right) consistently moving faster than the other. The lack of pattern persists throughout ontogeny.