To be precise, some evidence points in the direction that some variation in cognitive traits is “heritable”. Yes, this is more precise, but "heritability" is a

To be precise, some evidence points in the direction that some variation in cognitive traits is “heritable”. Yes, this is more precise, but "heritability" is a technical term that I try to avoid, because when some people are not familiar with its technical meaning, it leads to all kinds of confusion when others do use it in the technical meaning. On the other hand, "heritability" very much implies genetic causation in every meaningful sense. It is obvious to everyone that there are substantial effects on cognitive traits due to malnutrition, disease, exposure to toxins, physical violence, persistent emotional trauma It is by no means obvious. It depends on what you count as "substantial", what degree of malnutrition, what diseases, what toxins, what kind of physical violence, etc. It is at least plausible that large-scale differences in the treatment of boys vs. girls could have effects on cognitive traits. It is plausible, alas I have not seen much evidence for that effect. There is scarce evidence for malnutrition having effect of cognitive ability, but there is some. However, I haven't seen any evidence on shared or non-shared environment causing any sex differences in cognitive ability. but in some countries with more equal social/educational environments those differences in scores entirely disappear. I think this is rather more of an artifact of their educational systems putting finger on a scale where it wants. Consider, for example, that in both Iceland and Sweden, mentioned in the article as places where girls matched or exceeded boys achievement, 5 out of last 6 contestants on IMO were boys, and similar disparity happened in previous years. Instead of focusing on outliers, I recommend looking at the whole picture. It should be mentioned that Jensen’s work has been highly controversial and has kicked off a lively debate. Some of the biggest promoters of Jensen’s work have been quite unsavory characters. Like all scholarly work (and especially all work seized on more by activists than scholars) it should be read critically and taken in the context of a wider discourse. This is an argument without an argument, and smear by association. Jensen is the most renowned scientist in the field of psychometry and intelligence research. You imply that there's something wrong with him, but do not actually give any concrete criticism.