The third leg of the missing heritability problem is the mechanism gap. This refers to the fact that no matter what our estimate of heritability is, for human behavioral phenotypes we have essentially zero knowledge of how genetic differences produce behavioral differences. We can analyze variance, in Lewontin’s famous phrase, but we can’t analyze causes. All of the interesting within and between family work that Sasha (Gusev) catalogs is a step in the right direction, but the truth is there isn’t much progress toward actual mechanistic understanding. I personally doubt there ever will be (for complex human behavior), but that is another topic. The mechanism gap is crucial to my bet with Charles Murray, for example. Murray bet that by 2025 we would have IQ differences pretty much figured out, and that entails more than a reasonable estimate of a black-box heritability coefficient.
There are two especially interesting points, the first being Turkheimer's statement:
"...for human behavioral phenotypes we have essentially zero knowledge of how genetic differences produce behavioral differences."
Based on what I have learned about the claims of hereditarians, especially through my series on Adam Rutherford, (now in a convenient single-page format) I agree with this, as I went to great lengths to explain in my Rutherford piece.
But I suspect Jerry Coyne respects Turkheimer, who refers to himself in the same post as an "anti-hereditarian," in a way he does not respect me. Coyne has mentioned Turkheimer a few times on his blog and always respectfully, in spite of admitting that Turkheimer is opposed to race pseudoscience. Although I think Coyne likes Turkheimer in part because of Turkheimer's support for the ghastly Emily Willoughby. Coyne is a big supporter of Willoughby, and I'm sure her being chummy with neo-Nazis bothers him no more than Steven Pinker's alliance with the neo-Nazi ghouls of Aporia bothers him. In spite of Coyne's performative anxiety over antisemitism.
Hell, I bet that if Turkheimer bought a pair of cowboy boots, Coyne would let him join the Boot Boys.
The second interesting point in the paragraph is that Turkheimer had a bet with Charles Murray with Murray supporting the claim that:
"...by 2025 we would have IQ differences pretty much figured out."
Back in the pre-Musk days of Twitter, Murray had been mocked for his frequent predictions (see image above), since the publication of the Bell Curve, that his race pseudoscience beliefs would be vindicated through science.
It's Murray's true belief in race pseudoscience that makes him such an important thought leader of hereditarianism, enough so that even Turkheimer takes him seriously enough to make bets with him, instead of endlessly mocking him for being a grotesque old delusional racist crank.
Murray is as likely to stop believing in the eventual triumph of race pseudoscience as a devout Christian is likely to stop believing in the Second Coming. And these days, Murray is a devout believer of both sects.
Hereditarian Jonathan Haidt (a big fan of Natural History of Ashkenazi Intelligence) could be seen making a similar prediction back in 2009. These
days Haidt is writing for Bari Weiss' The Free Press, because of course he would.
days Haidt is writing for Bari Weiss' The Free Press, because of course he would.
Meanwhile Murray can be seen on X/Twitter joining with far-right political operative (and apparent employee of Emil Kirkegaard) "Cremieux" being mad about the efforts to retract the garbage of white nationalist Richard Lynn, from whom neo-Nazi Emil Kirkegaard inherited the remaining Pioneer fund assets.
Murray thinks Lynn was right about everything. But data will never matter to a true prophet like Charles Murray.
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| Right-wing political operative "Cremieux" (Jordan Lasker) seen hypocritically whining about someone else having "political reasons." ---------------------------------------------------------------------------------- |
In the same Substack post, Turkheimer snipes at Jay Joseph:
And the truth is, there aren’t many people writing these days who are willing to adopt a strictly zero-genetic-influence position. Jay Joseph is pretty much the only one I can think of.
I doubt this is exactly Joseph's position, as indicated by his comment on a Steve Sailer tweet. As I said, Sailer, a guy with a degree in marketing, is an important figure in hereditarian science, no doubt why Steven Pinker promoted Sailer's career for a decade.
I assume Joseph will have a direct response to Turkheimer's claim eventually.
Although at least Turkheimer has gotten fed up with Sailer and his obsession with race.
Turkheimer discussed his bet with Murray in an article in the Atlantic called Your Genes Are Simply Not Enough to Explain How Smart You Are, published in October:
Seven years ago, I took a bet from one of the most controversial figures in the scientific world. Charles Murray, the political scientist who—along with the late psychologist Richard Herrnstein—wrote The Bell Curve in 1994, wagered that one of his core ideas about genetics and intelligence would be proved true by 2025. He emailed me some time after I’d helped stoke an online furor about his insistent defense of The Bell Curve’s main points, which he’d recently reiterated on a popular podcast and which I, along with two other psychologists and intelligence researchers, had denounced in Vox. I took the bet because I was confident I would win.
Turkheimer then describes Murray's beliefs evident in "The Bell Curve," which is essentially the hereditarian Bible:
In The Bell Curve, Murray and Herrnstein argue that intelligence, as measured by an IQ score, is a crucial determinant of success in modern society. They also argue that a person’s intelligence is substantially determined by genetics, leading to the establishment of “cognitive elites” as intelligent people select one another for reproduction.
Based on Adam Rutherford's paper, and its accompanying cartoon, Rutherford appears to be in complete agreement with Murray.
On Bluesky, I asked Rutherford about Turkheimer's characterization of the Bell Curve and its apparent agreement with Rutherford's paper, but I don't expect a response, since he's never been anything but dismissive or insulting towards me, but if he does respond I will report it here.
The fact that there is "zero knowledge of how genetic differences produce behavioral differences" does not stop hereditarians from starting businesses based on this zero knowledge. Turkheimer mentions one of them, Herasight, run by several believers in race pseudoscience:
Phenotypic parental IQ accounts for something like half the variance in offspring IQ. A properly controlled PGS accounts for 5% on a good day. (The embryo testing company Herasight has recently made big claims that they can do better, but I will wait until I see a peer-reviewed paper.)
But promoting hereditarian claims as settled science has been around since at least when Pinker, Haidt and friends were promoting the Natural History of Ashkenazi Intelligence hypothesis.
To be completely fair to Murray, there are still 31 days left for his prophesy to come true. But it's not looking good.
