The article opens with a claim that (i) an individual's brain is wired in a way which makes change in IQ difficult for a set of healthy humans with IQ over a certain threshold which is basically orthogonal to the main thrust of the article (ii) that higher [potential] IQ has an evolutionary disadvantage
Sure, one can posit that (i) occurs because of (ii): i.e. (iii) to mitigate against the risk of people harming their reproductive ability by training up their IQ, the evolutionary process selects for immutable IQ
But that seems like a hypothesis with little to recommend it against the alternate hypothesis that mutability of IQ is neutral with respect to evolution but evolving brain structures whose performance in certain tasks can be radically improved in adulthood is difficult, period. Especially when one considers that high IQ at birth isn't eliminated from the gene pool, and marked increases in 1930-normalised IQ between generations doesn't appear to markedly disadvantage modern Westerners.
Similarly, it seems simpler to accept that the phenotype "potential 140 IQ" is the consequence of specific, rare combinations of certain genes which overall aren't correlated with survival, without positing side effects of IQ-linked genes. Ubermensch can't be bred because their kids aren't clones rather than because they're necessarily deficient in other ways.
I'd see the incidence of Tay Sachs disease as a counterexample to the theory that high performance in a specific brain function necessarily has evolutionary tradeoffs. Ashkenazi Jews on average test with higher verbal and mathematical intelligence and lower spatial intelligence than other ethnic groups, which could imply that human brains naturally-selected for optimal function in one area are punished in other areas. Ashkenazi Jews are also more likely to carry the recessive gene for the very rare and very debilitating Tay-Sachs disease. But since 26 out of 27 Ashkenazi Jews don't have that recessive gene, which afaik is uncorrelated with IQ amongst Ashkenazi Jews, it suggests the common factor between Askhenazi intelligence and Ashkenazi Tay-Sachs incidence is inbreeding. Reduced average spatial intelligence could, like Tay-Sachs, be the unfortunate effect of a restricted gene pool rather than an "tradeoff" which must inevitably be caused by higher scores in other tests.
> alternate hypothesis that mutability of IQ is neutral with respect to evolution but evolving brain structures whose performance in certain tasks can be radically improved in adulthood is difficult, period.
Merely 'difficult' is not much of a counter-argument - almost every component of a human being is at least 'difficult' to design. There doesn't seem to be reason to believe creating higher intelligence is especially more costly, in comparison to the already achieved intelligence.
But that seems like a hypothesis with little to recommend it against the alternate hypothesis that mutability of IQ is neutral with respect to evolution but evolving brain structures whose performance in certain tasks can be radically improved in adulthood is difficult, period. Especially when one considers that high IQ at birth isn't eliminated from the gene pool, and marked increases in 1930-normalised IQ between generations doesn't appear to markedly disadvantage modern Westerners.
Similarly, it seems simpler to accept that the phenotype "potential 140 IQ" is the consequence of specific, rare combinations of certain genes which overall aren't correlated with survival, without positing side effects of IQ-linked genes. Ubermensch can't be bred because their kids aren't clones rather than because they're necessarily deficient in other ways.
I'd see the incidence of Tay Sachs disease as a counterexample to the theory that high performance in a specific brain function necessarily has evolutionary tradeoffs. Ashkenazi Jews on average test with higher verbal and mathematical intelligence and lower spatial intelligence than other ethnic groups, which could imply that human brains naturally-selected for optimal function in one area are punished in other areas. Ashkenazi Jews are also more likely to carry the recessive gene for the very rare and very debilitating Tay-Sachs disease. But since 26 out of 27 Ashkenazi Jews don't have that recessive gene, which afaik is uncorrelated with IQ amongst Ashkenazi Jews, it suggests the common factor between Askhenazi intelligence and Ashkenazi Tay-Sachs incidence is inbreeding. Reduced average spatial intelligence could, like Tay-Sachs, be the unfortunate effect of a restricted gene pool rather than an "tradeoff" which must inevitably be caused by higher scores in other tests.