Figure 3.

Relationship between PSS scores and foraging behavior. A, Deviation from optimal scores conditional on the mixed-effects linear regression plotted as a function of PSS scores across all subjects. Note that positive values of this variable indicate underharvesting (i.e., desisting sooner than optimal) and negative values indicate overharvesting (i.e., desisting later than optimal). The regression line is computed from the group-level intercept and PSS fixed effects. Dashed lines indicate 2 SEs estimated from the group-level mixed-effects linear regression. B, Tree-by-tree data for a subject with a relatively low PSS score (based upon a median split). Solid lines indicate exit thresholds per tree as a function of time (y-axis), block (discontinuities between lines), and environment type (color). Dashed lines indicate subjects' average exit thresholds per block. Gray bars indicate optimal thresholds per environment type. C, Tree-by-tree threshold data for a subject with a relatively high PSS score. Subjects in B and C had comparable log cortisol Δ values. Note that, although both subjects are sensitive to environmental changes in the direction predicted by the MVT, the subject in C was biased toward suboptimally overexploiting trees.