Results from individual-based simulations, illustrating consequences of genetic conflict.

(A) Same as the simulations in Fig 2 except that a₀, in addition to a_g, in Eq (5) is determined by a single locus. The blue and red points (with error bars) show the deviating outcome for m = 0.10, ρ = 0.5, which is a consequence of genetic conflict between the cue locus and the locus encoding a_g: a_g became close to zero, but a₀ became polymorphic, and the polymorphism at the original cue locus collapsed. The outcome is further illustrated in (B), showing a kernel-smoothed distribution of phenotypes in a typical simulation. The blue and red vertical lines show the prediction from Fig 3C, where ρ = 0, and the blue and red dashed lines the prediction from Fig 3D, where ρ = 0.5. The outcome where an unlinked modifier (a₀) takes over the polymorphism depends on the genetic architecture, as illustrated in (B), (C) and (D). In (C) the modifiers a₀ and a_g in Eq (5) are each determined by several loci with small additive effects, and the loci contributing to a₀ all became polymorphic. In (D) there is a more complex architecture for a₀, with additive effects that in turn can be modified with an adjustable threshold limiting the amount of gene expression, and this threshold became polymorphic (see text and S1 Text for further explanation).