/sci/ - Science & Math

Taken from the wiki
https://en.wikipedia.org/wiki/Flynn_effect

"Some studies have found the gains of the Flynn effect to be particularly concentrated at the lower end of the distribution. Teasdale and Owen (1989), for example, found the effect primarily reduced the number of low-end scores, resulting in an increased number of moderately high scores, with no increase in very high scores.[15] In another study, two large samples of Spanish children were assessed with a 30-year gap. Comparison of the IQ distributions indicated that the mean IQ scores on the test had increased by 9.7 points (the Flynn effect), the gains were concentrated in the lower half of the distribution and negligible in the top half, and the gains gradually decreased as the IQ of the individuals increased.[16] Some studies have found a reverse Flynn effect with declining scores for those with high IQ."

What are some possible mechanisms for this bringing up the lower end?

-Improved nutrition, nonlocal food production, access to off season and more kinds of food
Nutrition, iodine in particular, aided neurodevelopment and reduced the impact of teratogens, infection, etc. As shipping increased regions with poor soil had better access to nutritious food. See eg the Appalachian regions during and after WW2.

-Improved sanitation, refrigeration
Reduced maternal and early childhood immune activation. Vaccination was a demonstrable failure however which spread disease, neurologically damaged, and infected many children.

-Improved medical knowledge
Despite clamping and other stupidity, improvements were mad eina reas like Rh factor incompatibility. eg It has been estimated that in the previous few centuries, in some regions like Ireland, Rh positive children of Rh negative mothers constituted a relatively high percentage of the mentally retarded or otherwise institutionalized.

There is no indication the population has been improved. As another anon noted, it's mostly just organizational synergy.