Bizarre that the second to top comment (on the linked page) immediately turned the conversation into one about the commenter's view on racial/sexual supremacy and goes on to say "correspondingly, there are also ethnicities that are less intelligent" (I'm assuming they are implying supremacy of their own group.) It's quite jarring the frequency one comes across white supremacist/misogynist talking points when one trie…
All he said is that some ethnicities are less intelligent than others. What is the statistical likelihood that 100% of ethnicities, which have evolved in drastically different environments across the world, have all developed perfectly identical intelligence on average? It's just not how evolution realistically works. People shouldn't close their eyes to how the world actually is whenever it doesn't match up with how…
If you measure the IQ for the same ethnicity you will notice that the IQ changes over time.
Having proper levels of iodine is responsible for about 15 points of IQ. Removing lead from fuel, some extra increase.
Pollution, nutrition, water purity, all the accrued knowledge about fetal and child development that is applied in modern economies, etc. plays a role.
Also, there are negative factors like exposure to violence and trauma, substance abuse, which is correlated with poverty and inequality... which is a legacy of slavery, racial segregation, etc.