Fig. 4

Directional entropy of sea urchin trajectories. a The directional entropy of sea urchins in the control treatment (blue, n = 29) was higher than for sea urchins subjected to predator cues (orange, n = 21). b The directional entropy of sea urchins’ trajectories decreased with steeper slopes of the scaling exponents of the qth order moments (ζ(q)), indicating that the predictability of individual trajectories increases as we move from Brownian motion towards ballistic movements. Points correspond to each individual observation and shaded areas in (b) correspond to 95% confidence intervals