HIGHER EDUCATION BUBBLE UPDATE, GENETIC DECLINE EDITION: Natural selection is causing a decline in human ‘education genes’, say scientists.

A study involving more than 100,000 people in Iceland found that those who carry the genes for longer education time were less likely to have a big family, which means the smartest people in the room were actually contributing less to the Icelandic gene pool. . . .

Once that polygenetic score was correlated with factors like educational attainment, fertility, and birth years, the researchers found that those with a higher genetic propensity towards more education tended to have fewer children.

They also found that the average polygenetic score has been declining at a small, but significant rate on an evolutionary timescale.

As Ian Sample reports for The Guardian, the team found a drop in IQ of about 0.04 points per decade, but if all the genetic factors that could be linked to education were taken into account, that figure would increase to 0.3 points per decade.

Interestingly, the link between a higher propensity towards more education and having fewer children wasn’t because going to university is hard, and eats into your family-raising time – the team suggests that the genes involved in education can also affect human fertility on a biological level.

Because even those who carried the genes for longer education time, but who did not actually get more education, still had fewer offspring on average than those without the genetic factor.

This may explain why humanity hasn’t gotten steadily smarter.