Figure 5 .

The coevolution recombination modifiers and a two-locus drive system. The frequencies of drive enhancer, centromeric driver, and recombination modifier alleles are displayed in red, green, and blue, respectively. The correlation between recombination modifier and centromeric driver alleles is denoted by the green and blue line, and its value is given on the right axis in B (the scale is maintained in C). Initial frequencies of drive and recombination modifier alleles equal $f_{D_0}=0.10$ and $f_{M_0}=0.01$, respectively. The driving centromeric allele completely distorts meiosis in DD and Dd genotypes (e.g., α₁ = α₂ = 1) and is a recessive lethal. Neither drive enhancer nor recombination modifier directly influences individual fitness. The initial recombination rate and allele frequencies are r = 0.10 and f_D(0) = f_C(0) = f_M(0) = 0.001, respectively. (A) Recombination modification in both sexes (δr_♀ = 0.025, δr_♂ = 0.025). (B) Female-limited recombination modification (δr_♀ = 0.025, δr_♂ = 0). (C) Male-limited recombination modification (δr_♀ = 0, δr_♂ = 0.025). (D) The modifier has distinct influence on male and female recombination rates (δr_♀ and δr_♂, respectively). Green indicates an increase in modifier frequency, and purple indicates a decrease. Labels above diagonal lines describe the relative change in allele frequencies over 250 generations.