Einherjar86
Active Member
This is a welcome piece, and it lays out a lot of the methodological problems with race science. The resistance to genetic explanations aren't entirely political, despite what the race scientists proclaim. There's actually a lot of bad science in those studies.
https://www.theguardian.com/news/2018/mar/02/the-unwelcome-revival-of-race-science
https://www.theguardian.com/news/2018/mar/02/the-unwelcome-revival-of-race-science
A second plank of the race science case goes like this: human bodies continued to evolve, at least until recently – with different groups developing different skin colours, predispositions to certain diseases, and things such as lactose tolerance. So why wouldn’t human brains continue evolving, too?
The problem here is that race scientists are not comparing like with like. Most of these physical changes involve single gene mutations, which can spread throughout a population in a relatively short span of evolutionary time. By contrast, intelligence – even the rather specific version measured by IQ – involves a network of potentially thousands of genes, which probably takes at least 100 millennia to evolve appreciably.
Given that so many genes, operating in different parts of the brain, contribute in some way to intelligence, it is hardly surprising that there is scant evidence of cognitive advance, at least over the last 100,000 years. The American palaeoanthropologist Ian Tattersall, widely acknowledged as one of the world’s leading experts on Cro-Magnons, has said that long before humans left Africa for Asia and Europe, they had already reached the end of the evolutionary line in terms of brain power. “We don’t have the right conditions for any meaningful biological evolution of the species,” he told an interviewer in 2000.
In fact, when it comes to potential differences in intelligence between groups, one of the remarkable dimensions of the human genome is how little genetic variation there is. DNA research conducted in 1987 suggested a common, African ancestor for all humans alive today: “mitochondrial Eve”, who lived around 200,000 years ago. Because of this relatively recent (in evolutionary terms) common ancestry, human beings share a remarkably high proportion of their genes compared to other mammals. The single subspecies of chimpanzee that lives in central Africa, for example, has significantly more genetic variation than does the entire human race.
No one has successfully isolated any genes “for” intelligence at all, and claims in this direction have turned to dust when subjected to peer review. As the Edinburgh University cognitive ageing specialist Prof Ian Deary put it, “It is difficult to name even one gene that is reliably associated with normal intelligence in young, healthy adults.” Intelligence doesn’t come neatly packaged and labelled on any single strand of DNA.