Fig. 2.

Effects of gene flow on the evolution of trait matching in mutualistic networks. (A and B) Each point is the mean trait matching at equilibrium at the hotspot (${\overline{\tau }}_A*$) for 100 simulations parameterized with a seed dispersal network (network 64 in SI Appendix, Table S1), and bars show the 95% confidence interval. (A) When mutualistic selection is high at both sites (${\overline{m}}_A={\overline{m}}_B=0.7$), gene flow favors trait matching at each hotspot. (B) When mutualistic selection is high at only one site (${\overline{m}}_A=0.9$, ${\overline{m}}_B=0.1$), gene flow reduces trait matching at the hotspot. Changes in mean trait matching (A and B) are a consequence of changes in the matching among generalist species, as shown in the interaction matrices (colors depict equilibrium pairwise trait matching for one simulation with the indicated value of gene flow). Sample distributions and values for simulation parameters: ${\phi }_{i,A},{\phi }_{i,B}\sim \mathcal{N}\left[\mu =0.5,{\sigma }^2=10^{-4}\right]$, ${\theta }_{i,A}\sim \mathcal{U}\left[\mathrm{0,10}\right]$, ${\theta }_{i,B}\sim \mathcal{U}\left[\mathrm{10,20}\right]$, $m_{i,A}\sim \mathcal{N}\left[{\overline{m}}_A,10^{-4}\right]$, $m_{i,B}\sim \mathcal{N}\left[{\overline{m}}_B,10^{-4}\right]$, $g_i\sim \mathcal{N}\left[\overline{g},10^{-6}\right]$, and $\alpha =0.2$.