Figure 1.

Equilibrium genetic diversity at a locus that harbors alleles with sex-specific fitness effects. Gray curves follow the frequency of an allele that is costly to sex 1 (each copy of the allele reduces fitness by amount s_i; see the text for details). Black curves depict heterozygosity at the locus. The fitness effect on the other sex (sex 2) is also negative when t_i > 0 (i.e., t_i/s_i > 0). Its effect is positive, and the allele is sexually antagonistic, when t_i < 0 (i.e., t_i/s_i < 0). Results are based on numerical evaluation of the roots of Δq_i = 0 [see eqn (1) and Supporting Information], with u = 10⁻⁶.