I came across this map of German performance in math, biology, physics, and chemistry in the IQB-Ländervergleich 2012, a test they hold once every few years in conjunction with PISA.

With the sole exception of Berlin, which is close to rock bottom, the former GDR states along with Bavaria were consistently at the top of the ratings. 50-60 points difference correspond to two years’ worth of learning progress.

Saxony, home of Pegida and known in the Cold War as the “valley of the clueless” because its specific geography hampered Western radio and TV broadcasts, is at the very top.

This is confirmed by the regional PISA results for 2009.

What could possibly explain this?

Who could have imagined?

In reality, East Germans are nothing special academically; they are about mid-range compared to the average ethnic German elsewhere in Germany.

The key difference is that East Germans had yet to be really enriched back when these tests were carried out. The map above shows the percentage of immigrants in the German districts as of 2011.

On a historical note, it’s possible that the roots of the South German – that is, Bavaria and Baden-Wuerttemberg – dominance on the German cognitive scoreboard are pretty old.

Thirty years after the printing press first appeared in Europe, you could already begin to discern three distinct clusters of concentration – Northern Italy, the Low Countries, and South Germany. (The first two, of course, were famous for their respective Renaissances). Back then, there was no independent Protestant pro-literacy effect, so we might expect to see a considerable correlation across Catholic Europe between literacy rates and IQ (though back then climatic factors would had a much bigger influence in suppressing literacy rates in the colder, less urbanized areas of Northern Europe). And it is reasonably to suppose that there was likewise a good correlation between literacy rates and the adoption of the printing press.

Furthermore, unlike the Low Countries and Italy, South Germany is a hilly inland area, an environment that tends to depress IQ (iodine deficiency – the European alpine areas used to be known for having many cases of goitre and cretinism), so their achievement in quickly accumulating such a high density of printing presses nonetheless must have already hinted at a very respectable genotypic IQ.

I seem to recall reading in National Literacy Campaigns and Movements, as in Sweden, there were ecclesiastical reglaments making marriage more difficult for illiterate people in southern Germany from the 18th century. If so this would have been a eugenic policy that helped maintain or increase further those high IQ levels, though the effect would have been attenuated by the Bavarians having one of Europe’s highest illegitimacy rates (something like 27% IIRC).