Effect of Migration on Genetic Distance

The effect of migration on genetic distance has been studied with a finite island model for the following two cases: constant migration rate and decreasing migration rate. Results based on the assumption that migration rate decreases with time are very different from those based on the assumption of constant migration rate. Numerical results indicate that in studying gene differentiation between species or taxa of higher rank we may assume that there was no migration between the two taxa from the very beginning of separation.