Fig. 8. Plots of jet angle versus (A) path of motion angle and (B) ring axis angle for Triakis semifasciata. The solid lines indicate a significant linear regression, while the dotted lines represent the predicted relationships (see text for discussion). Jet angle has a significant negative correlation with path angle (y=-29-1.045x; P<0.001, r²=0.257) and parallels the predicted relationship in which vortex jets are oriented in a direction opposite to the path of motion. Jet angle decreases with increasing ring axis angle at a slower rate than expected assuming a perpendicular relationship (y=34.720-0.519x; P<0.001, r²=0.291). Circles, triangles and squares represent holding, rising and sinking, respectively.