A recent article (Will ye nae come back again? Economist vol. 433 no. 9166 October 26, 2019 page 71) has found that people are moving out of the old coal towns that did their work while British industry and heating were more reliant on coal. That is hardly a surprise, since there is far less work left to do in such areas. But they top it off by claiming that those who are moving away have genetic markers (single nucleotide polymorphism sites or SNPS) that are thought to promote greater success. Thus those left behind are less blessed in that regard.
Of course, old Economist is, and has been ever since it was set up so many decades ago by the super-rich, globalist to the hilt. They must have looked far and wide to find this one. You can see how the politics plays out. “The brightest and best are moving, so immigrants to the UK must be their brightest and best.” The fact that the home countries can ill afford to lose talent, of course, is not going to come up for mention, although it’s OK for them to hint at the same problem for the miners’ descendants.
And they will not, short of being at sword point, ever whisper that the very process of moving means that those clever folks will not marry kin, will suffer decreased fertility, and everybody loses.