Figure 6. Premnas biaculeatus follow the rotating filter in the full polarization treatment.

Larval position, measured at 2(θ; Y-axis); as the axis changes its direction relative to the sun (α; X-axis). Different colors represent different larvae, under partial and full polarization (panels A & B). Points along the equality line (dashed line) depict larvae swimming towards the sun. Horizontal sequences of points (marked by red arrows) depict larvae that track the polarization axis, as it rotates along with the DISC.