Grackle reinforcement learning. Behaviour. Across-population learning speed and choice-option switches in (A-B) initial (M, 32; F, 17) and (D-E) reversal learning (M, 29; F, 17), with (C,F) respective posterior estimates and M-F contrasts. Mechanisms. Within- and across-population estimates and contrasts of information-updating rate φ and risk-sensitivity rate λ in (G,I) initial and (H,J) reversal learning. In (G-J) open circles show 100 random posterior draws; red filled circles and vertical lines show posterior means and 89% HPDI, respectively. Simulations. Learning speed and choice-option switches by: 10,000 full posterior-informed ‘birds’ (n = 5,000 per sex) in (K-L) initial and (N-O) reversal learning; and six average posterior-informed ‘birds’ (n = 3 per sex) in (M) initial and (P) reversal learning. In (K,N) the full simulation sample is plotted; in (L,O) open circles show 100 random simulant draws. Note (K,N) x-axes are cut to match (A,D) x-axes. Medians are plotted/labelled in (A,B,D,E,K,L,N,O).
Figure 2—figure supplement 1. Excluding extra learning trials.