Simulation results. The probability of detecting historic, migrant alleles under all combinations of 4 essential genetic parameters. The average final migrant allele frequency of 250 replications of each parameter set is reported as the mean (μ) frequency of migrant alleles. The standard deviation (σ) of the 250 replications is reported for each parameter set below the corresponding mean. The two parameter sets with the highest and lowest mean allele frequencies are in bold.