Anon on Reddit writes me:

Hey, Emil! I’ve been a fan of your work for a while now. I respect your effort to give a voice to persecuted research directions. After reading your blog and seeing you on Reddit, I couldn’t help but respond with some information you may find helpful.

—Non-human Primates in colder climates may exhibit greater intelligence—

You mention in this post: https://emilkirkegaard.dk/en/?p=6472 that finding a relationship between intelligence and cold climates in other animals may be a strong indicator that it could have operated similarly in humans.

This study: https://royalsocietypublishing.org/doi/full/10.1098/rstb.2015.0186 attempted to quantify some measures of intelligence across non-human primate species. They have an enormous database containing different species, so I scrolled through.

According to this database, Japanese Macaques (the most northerly and cold-adapted primate other than ourselves) vastly outperform other Macaque species in tests of cognition (wider variability in tool use, etc.).

Some of the other Macaque species are clearly less studied, but that’s certainly not true of Rhesus Macaques (of subtropical and tropical southern Asian climates). Rhesus are the typical lab monkey.

—East Asian IQ and Latitude—

You mention in this post: https://emilkirkegaard.dk/en/?p=7140 that the high East Asian IQ is seen by some as a positive outlier. It doesn’t pair well with the pattern of increasing IQ toward higher latitude.

That’s true, but (as you suspected) latitude isn’t a perfect correlate with climate.

Eastern sides of continents have drastically colder winters than western sides. The difference is dramatic.

Paris, France, at ~48 degrees latitude has an average January Low of 2.7ºC.

compare this to:

Khabarovsk, Russian Far East, at ~48 degrees latitude has an average January Low of -23.5ºC.

Beijing, China, at ~39 degrees latitude has an average January Low of -8.4ºC.

compare this to:

Valencia, Spain at ~39 degrees latitude has an average January Low of 7.1ºC.

or even:

Madrid, Spain at ~40 degrees latitude has an average January Low of 2.7ºC (despite being at a significantly higher elevation than Beijing).

Shanghai, China at ~31 degrees latitude has an average January Low of 2.1ºC.

compare this to

Essaouira, Morocco at ~31 degrees latitude has an average January Low of 11.2ºC.

This pattern is true in North America as well, although the western mountain ranges confine the milder oceanic climate of the west to a narrow sliver:

Seattle, USA at ~47 degrees latitude has an average January Low of 2.7ºC.

compare this to:

Miramichi, Canada at ~47 degrees latitude has an average January Low of -16.6ºC

There are indeed some good datasets out there. Unfortunately, during our cultural revolution, very few people want to take the time to look into these and run even obvious models. Why would they? One can get canceled and fired for anything these days. Even Magic cards depicting completely fictional creatures get banned (Sargon, random site).

That said, Japanese Macaques are pretty cool: