Brad’s calculation is a bit unrealistic. Most traits are controlled by large numbers of genes and there is a huge amount of extant variation, even within families. No new mutations or special “patience genes" are required for evolutionary change.A more realistic calculation, that takes into account heritabilities less than one, limited correlation between phenotype and reproduction rate, etc. leads to about 1000 years as the fastest timescale for shift in population mean of about one standard deviation. There has been plenty of time since the dawn of civilization or of agriculture for humans to have changed significantly. A few hundred years is probably not enough time except perhaps in some exceptional cases of really strong selection. I doubt Clark is right that the industrial revolution is primarily a consequence of selection driven pressure in England, although I agree that the British today are probably quite different from their ancestors one or a few thousand years ago.http://infoproc.blogspot.com/2011/08/demography-and-fast-evolution.htmlApologies for typos — getting used to an iPad.
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