I Just skimmed it. (The author is a parapsychologist crank and racist, the publisher is predatory and the journal is low quality I'm not going to spend time rea

I Just skimmed it. (The author is a parapsychologist crank and racist, the publisher is predatory and the journal is low quality I'm not going to spend time reading it.) People frequently misunderstand how genetics interacts with IQ and educational attainment. The IQ differences between regions exist mostly because the IQ distributions are skewed. East Africa is the prime example. #1 The IQ distribution in East Africa is very skewed. The average IQ is so low because there is so many people with cognitive deficits due to sickness or pre- and postnatal malnutrition. If you remove the skew, you get average IQ with that aligns with the rest of the world. Nutrition and parasite load together explain practically all of the IQ differences between regions. #2 These polygenic scores include genes that are related to immune system and nutritional intake (nutrient absorption, utilization and tolerance). Genes that control the immune system and nutritional intake correlate very highly with IQ in developing countries. Their effect is smaller but not nonexistent in developed countries. Making gene/environment distinction is hard. It's easier to make between individuals in the same ethnic groups in the same environment. Everywhere else they mix. For example nutrigenomics and nutrigenetics are related to IQ trough the environment.