This is very nice, very interesting new paper out by Yair Field, Evan Boyle et al: they present a new method that can detect human adaptation over the past couple of thousand years. And there is some, of course. They found strong signs of selection at lactase and HLA, and in favor of blond hair and blue eyes. This new method (SDS, Singleton Density Score) can also detect signs of polygenic selection, and they found that selection for increased height ‘has driven allele frequency shifts across most of the genome’.
They found evidence for selection acting on other polygenic traits: favoring increased infant head circumference, increased female hip size, and later sexual maturation in women.
You can do a million cool things with this method. Since the effective time scale goes inversely with sample size, you could look at evolution in England over the past 1000 years or the past 500. Differencing, over the period 1-1000 AD. Since you can look at polygenic traits, you can see whether the alleles favoring higher IQs have increased or decreased in frequency over various stretches of time. You can see if Greg Clark’s proposed mechanism really happened. You can (soon) tell if creeping Pinkerization is genetic, or partly genetic.
You could probably find out if the Middle Easterners really have gotten slower, and when it happened.
Looking at IQ alleles, you could not only show whether the Ashkenazi Jews really are biologically smarter but if so, when it happened, which would give you strong hints as to how it happened.
We know that IQ-favoring alleles are going down (slowly) right now (not counting immigration, which of course drastically speeds it up). Soon we will know if this was true while Russia was under the Mongol yoke – we’ll know how smart Periclean Athenians were and when that boost occurred. And so on. And on!
Feel free to mention some of the theories (distilled horseshit, mostly) that are likely to bite the dust, between SDS and aDNA.
“The pace has been so rapid that humans have changed significantly in body and mind over recorded history.”