Figure 1.
(a) Average and (b) standard deviation of phenotype Yi in the population, as a function of generation time, over 40 000 generations. The parameters are: α =−4, β = 4, μ = 10−4, τ = (−1, −1, −1, −1, 1, 1, 1, 1), γ = (−1, −1, −1, −1, 1, 1, 1, 1)/2 and N = 10 000 individuals. The environment changes periodically every five generations and the simulation starts with an isogenic population at the X genes, Xi = (0, 0, 0, 0, 0, 0, 0, 0). There are three different initial conditions for the M genes: for every individual in the first generation, each one of its eight M genes is 0 with probabilities 0.9 (red curve), 0.5 (green curve) or 0 (blue curve). Each point represents the average across 100 different runs of the simulation. The curves represent a fit to the data using a generalized additive model with penalized cubic regression splines.