Migration maintains genetic variation only within an intermediate optimal range

Evidence

By introducing an island model of migration in which all subpopulations receive migrants representing the average gene frequency of all subpopulations pooled, i.e., the metapopulation, one finds that a small amount of migration can counteract drift effects. Thus, one readily accepts the general notion that migration promotes the maintenance of genetic variation. However, as noted below, several models show that too much or too little migration may not help retain variation. … Specific models of migration make an enormous difference in the distribution pattern of genetic variation. — S. T. A. Pickett and P. S. White, eds., The Ecology of Natural Disturbance and…, 1820

Categorization

• XREF: connects to: Restricted dispersal alone can generate persistent patchy genetic variation even in large populations — S. T. A. Pickett and P. S. White, eds., The Ecology of Natural Disturbance and…, 1822; Patch turnover rate governs mutant fate when extinction outpaces migration — S. T. A. Pickett and P. S. White, eds., The Ecology of Natural Disturbance and…, 1823