Fig. 2.

Residual proportion of devices solved (mean ± SEM) in relation to total group sizes in low and high perceived predation-risk positions (low risk was near cover, filled circles; high risk was far from cover, open circles). Plotted values are residuals from a binomial GLMM of proportion of solved devices for group effort, with trial nested within day and location as random effects (n = 324, split into seven categories of 20 and one category of 22 data points, allocated separately for data points near and far from cover).