Over this period, all but the most isolated populations should have had ample time to reach a dynamic equilibrium between migration, genetic drift, and local adaptation.
Genotypic variation in selfing capacity thus seems present across the species' European distribution, but selfing rates were consistently higher for genotypes from the most isolated populations.
Effective population size was greater than census population size in all but the two most isolated populations, Blue Hill and WD, which do not appear to be experiencing limited diversity in available pollen.
In this study, we found the same genetic variation pattern both at neutral and MHC markers, suggesting that genetic drift was stronger than selection, thus leading to a reduction in MHC diversity in the most isolated populations.
Overall, the genetic distance between the most isolated populations within a given taxon was highest for hybrids (~0.55), half as great for D. longispina (~0.25), and one-tenth as great for D. galeata (~0.055, Figure 4).
In the study populations, greater gene flow occurred between the nearest populations (distance from 300 to 500 m), while the rate of gene flow decreased in populations farther from each other (distance from 1000 to 1500 m) and there was little or no inter-population gene flow between the three smallest and most isolated populations (Fig. 2).
Conversely, the Afghan Kyrgyz are surely one of the most isolated pastoral populations in the world - the story of the exodus of part of the population to Turkey during the Soviet-Afghan war and the survival of the remainder in the remote Wakhan corridor is extraordinary.
Genetic testing results published in 2001 indicated that Namib Desert Horses are one of the most isolated horse populations in the world, with the second-lowest genetic variation of all horse populations that have been studied to date.
