Figure 3.

Simulation of the invasion of an inversion in a cline. Two haploid loci with multiplicative fitness effects are initially at a migration–selection equilibrium in a stepping-stone population with 10 demes. At each locus, one allele has fitness 1 + s to the left of the midpoint and fitness 1 − s to the right. An inversion that captures the locally favored haplotype is introduced in the central deme at an initial frequency of 0.01. (A) The invasion of the inversion. (B) The extinction of the ancestral recombining haplotype that carries the same alleles as the inversion. (C) The extinction of recombinant haplotypes as the inversion invades. Parameters are s = 0.025, m = 0.1, and r = 0.5. Note the change in the vertical scale in C.