Figure 4.

${\overline{F}}_{\mathrm{ST}}/{\overline{F}}_{\max },$ the ratio of the mean $F_{\mathrm{ST}}$ to the mean maximal $F_{\mathrm{ST}}$ given the observed frequency M of the most frequent allele, as a function of the number of subpopulations K and the scaled migration rate $4Nm$ for the island migration model. Colors represent values of K. $F_{\mathrm{ST}}$ values are computed from coalescent simulations using MS for 10,000 independent SNPs and 100 lineages sampled per subpopulation. ${\overline{F}}_{max}$ is computed from Equation 11. Figure S4 in File S1 presents similar results under rectangular and linear stepping-stone migration models.