Figure 2.

Ecological dynamics. (a,b) Basic reproductive ratios for (a) social information $(k=I)$ and (b) infection $(k=D)$ as a function of the contact effort, E. Curves correspond to the basic reproductive ratio in the full model, $R_0^k$ (black, solid), the full model without infection or social information present, ${\widehat{R}}_0^k$ (blue, dotted), and the approximation for fast social information dynamics, ${\stackrel{\sim }{R}}_0^k$ (red, dashed). (c,d) Comparison of the nontrivial equilibria in the full model (solid) and the approximation for fast social information (dashed). All parameters except for τ and σ are fixed, with $\sigma /\tau =10$ held constant. The full model approaches the approximation when social information dynamics are fast relative to other processes. (c) Proportion of individuals in each class. (d) Proportion of individuals that are infected (green) or are in the good information state (purple). Fixed parameters (where applicable): $a=0.2$, $b=1$, $d=0.5$, $E=4$, $q={10}^{-3}$, $\alpha =0.4$, $\beta =0.1$, $\gamma =0.2$, $\sigma =1$, $\tau =0.1$