“Holocene Selection for Variants Associated With Cognitive Ability: Comparing Ancient and Modern Genomes”, 2017-02-21 (; similar):
Human populations living in Eurasia during the Holocene experienced evolutionary change. It has been predicted that the transition of Holocene populations into agrarianism and urbanization brought about culture-gene co-evolution that favoured via directional selection genetic variants associated with higher general cognitive ability (GCA). Population expansion and replacement has also been proposed as an important source of GCA gene-frequency change during this time period.
To examine whether GCA might have risen during the Holocene, we compare a sample of 99 ancient Eurasian genomes (ranging from 4,557 to 1,208 years of age) with a sample of 503 modern European genomes, using 3 different cognitive polygenic scores. differences favouring the modern genomes were found for all 3 polygenic scores (Odds Ratio=0.92, p = 0.037; 0.81, p = 0.001 and 0.81, p = 0.02). Furthermore, a statistically-significant increase in positive allele count over 3,249 years was found using a sample of 66 ancient genomes (r=0.217, pone-tailed = 0.04).
These observations are consistent with the expectation that GCA rose during the Holocene.