Expected fog-2 genotype frequency dynamics during transitions. (A) Compound likelihood curves of the outcross-fitness values (α) that in simulations of trioecious experimental evolution can explain the observed fog-2(wt) allele frequency dynamics in the sudden population (black) and in the gradual populations (grey). Grey bars indicate the credible interval of -2lnLk around the maximum-likelihood (ML) estimate. Circle shows the expected outcross-fitness component value (α) with one SE in the lab-adapted population, using the data from Figure 2A (see Methods). (B) Deterministic fog-2(wt) allele trajectories expected with the ML α estimates (lines). Circles and error bars are the observed trajectories (as in Figure 4C). Dashed lines illustrate the deterministic fog-2(wt) frequency dynamics if there is no cost of males as modelled with α =1. See also Additional file 1: Figure S8 for the sex ratio experimental evolution expectations. Simulations assumed random mating and selfing and no sex segregation distortion (see Additional file 1: Table S2).