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Chanda Chisala has been producing pile after pile of nonsense for quite some time. At first, I was content with simply leaving comments at his posts refuting his rubbish because it was rather easy to point out where he was full of baloney. Since then, I’ve been banned by him, mostly for my signature flair.
I intended to continue to ignore his nonsense since it was such obvious rubbish that it didn’t seem to be worth my (now very precious) time. But then I realized the value of having nonsense essays picked apart for the nonsense they are. Rebuttals are highly valuable to skeptical readers who doubt nonsense but can’t quite put their finger on the problems themselves. So, in that service, I write this rebuttal to Chisala’s latest piece.
Chisala’s theory is that different human groups differ in the degree of genetic canalization, and that explains the differences in average IQ between groups. It seems he lifted the concept of genetic canalization from Greg Cochran, who I’ll let describe the phenomenon. From Survival of the Flattest | West Hunter :
Genetic canalization is the extent to which an organism is buffered against the effects of mutations. Waddington said “developmental reactions, as they occur in organisms submitted to natural selection…are adjusted so as to bring about one definite end-result regardless of minor variations in conditions during the course of the reaction”. Canalization can act to buffer against environmental perturbations, and selection for resistance to such environmental noise may also produce resistance to genetic noise. But right now I’m thinking about genetic canalization.
Up to some point, the effects of not too many, not too serious mutations would be buffered: those mutations wouldn’t change the phenotype. In the same way, your typical tractor is not designed to nanometer tolerances: parts can be somewhat out of spec – up to some limit – without messing up performance.
Canalization is a product of natural selection. There would be stronger selection for efficient canalization in a species with more genetic load
It might explain why load doesn’t seem to have much effect on IQ over most of the range, why we haven’t seen general IQ depression in the children of old men.
So Chisala’s idea is that certain racial groups have greater levels of canalization, and that makes them more resistant to environmental stresses that might lower average IQ.
Oh God! Where to begin….
It’s hard for me tell if Chisala really believes what he’s saying. Because the truth of the matter is that he’s a bullshit artist, either wittingly or unwittingly. It appears that he has only a superficial understanding of the matters he discusses, and he tries to weave together cherry-picked pieces of information into a seemingly convincing story – at least for those who don’t know any better.
First of all, Chisala is claiming that there are no “genetic” group differences in IQ. Rather, every group has the same average IQ potential, but each group has a different level of canalization, thanks to natural selection (and this is not even genetic canalization – as in resistance to mutations – as Cochran discussed, but resistance to purported environmental insults). This makes each more or less resistant to the purportedly IQ-depressing effects of deprived environment. So first it’s not genetic, but it is? Which is it, man?
Second, Chisala seems to have no understanding of the concepts of elite samples, founder effects, measurement error, sampling bias, or of basic statistical principles like statistics of small numbers. That’s not even to mention his apparent lack of understanding of the breeder’s equation (but at least there he has plenty of company). He seems to be mystified by apparent incongruities he encounters in his cherry-picked (and often outdated) samples because of his ignorance of these important concepts and many other facts.
I’m not going to debunk Chisala’s claims point-by-point, because, really that’s not necessary (and his piece is much to confused to make that a worthwhile endeavor). Instead, I’m going to point out some key facts make his claims ridiculous.
One of those key facts is this:
There are global differences in brain size. Brain size is certainly related to intelligence, both on the individual level (Pietschnig et al 2015) and (even more so) on the group level (though the both the group level and individual level correlations are less than 1.0). In order for Chisala’s idea to work, these environmental insults must also cause certain racial group differences in brain size.
But, as we know, it’s not outside the realm of possibility that environmental insults can affect brain size (see the Zika virus). And sure, sub-Saharan Africa is loaded with pathogens and other environmental insults. But racial differences in brain size are seen between people of European, African, and Asian ancestry in the United States (from Rushton & Jensen, 2010):
(At this point, of course, we cue the sociologist’s fallacy invoking the poorer environments of Blacks even in the U.S.) But, Chisala is claiming Blacks are more susceptable to environmental insults that supposedly affect IQ – insults that (save perhaps iodine deficiency) have not been shown to actually impact IQ in any way. I’ll go into more detail in a future post, but there is little solid evidence for a negative impact of most supposed environmental insults on IQ.
For now, I’ll give you Greg Cochran on this (from The Great IQ Depression | West Hunter):
We hear that poverty can sap brainpower, reduce frontal lobe function, induce the fantods, etc. But exactly what do we mean by ‘poverty’? If we’re talking about an absolute, rather than relative, standard of living, most of the world today must be in poverty, as well as almost everyone who lived much before the present. Most Chinese are poorer than the official US poverty level, right? The US had fairly rapid economic growth until the last generation or so, so if you go very far back in time, almost everyone was poor, by modern standards. Even those who were considered rich at the time suffered from zero prenatal care, largely useless medicine, tabletless high schools, and slow Internet connections. They had to ride horses that had lousy acceleration and pooped all over the place.
In particular, if all this poverty-gives-you-emerods stuff is true, scholastic achievement should have collapsed in the Great Depression – and with the miracle of epigenetics, most of us should still be suffering those bad effects.
But somehow none of this seems to have gone through the formality of actually happening.
Of course, it’s also worth mentioning that brain structure differs detectably by race, as previously discussed:
a new paper, Fan et al 2015, that the details of cortical surface structure of the brain is highly predictive of genetic ancestry. Indeed, as Fan et al put it:
Here, we demonstrate that the three-dimensional geometry of cortical surface is highly predictive of individuals’ genetic ancestry in West Africa, Europe, East Asia, and America, even though their genetic background has been shaped by multiple waves of migratory and admixture events. The geometry of the cortical surface contains richer information about ancestry than the areal variability of the cortical surface, independent of total brain volumes. Besides explaining more ancestry variance than other brain imaging measurements, the 3D geometry of the cortical surface further characterizes distinct regional patterns in the folding and gyrification.
Indeed, an earlier paper from this team (Bakken, Dale, and Schork, 2011) found that this works within racial groups as well, as the case with Europeans (see also the section Intraracial Group Variation below):
In our group’s previous study, we found that area measures of cortical surface and total
brain volumes of individuals of European descent in the United States correlate significantly with their ancestral geographic locations in Europe
Published Genome Wide Association Studies (GWAS), reporting the presence of alleles exhibiting significant and replicable associations with IQ, are reviewed. The average between-population frequency (polygenic score) of nine alleles positively and significantly associated with intelligence is strongly correlated to country-level IQ (r = .91). Factor analysis of allele frequencies furthermore identified a metagene with a similar correlation to country IQ (r = .86). The majority of the alleles (seven out of nine) loaded positively on this metagene. Allele frequencies varied by continent in a way that corresponds with observed population differences in average phenotypic intelligence.
Here is a scatter plot from the paper:
Going even beyond this, if we follow Chisala’s logic and assume that somehow adverse reactions to the environment are responsible for the size, structural, and performance differences of African brains relative to other groups, then we have another problem: the performance difference between different human groups isn’t a 20th and 21st century phenomenon only – it goes back for the entirety of recorded history.
As we’ve seen before, and as Bryan Caplan recounts, the differences between human groups in development goes back thousands of years – such that level of development as far back as 1000 B.C. is predictive of development today. Indeed, as Easterly, Coming, and Gong (2007) recount:
We assemble a dataset on technology adoption in 1000 B.C., 0 A.D., and 1500 A.D. for the predecessors of today’s nation states. We find that this very old history of technology adoption is surprisingly significant for today’s national development outcomes. Although our strongest results are for 1500 A.D., we find that even technology as old as 1000 B.C. is associated with today’s outcomes in some plausible specifications.
It’s not like the poor performers and the strong performers of today are a new thing. They’ve been poor performers and strong performers throughout history (by and large). Indeed, in sub-Saharan Africa (emphasis mine):
Why this meandering reminiscence of mine about a random ruin in Turkey? Because sub-Saharan Africa has remarkably few ruins for its immense size.
This fact is not well known. It is so hazy in the contemporary mind that Henry Louis Gates managed to sell PBS on a six episode miniseries about African ruins called The Wonders of Africa without, apparently, anybody in PBS management calling his bluff about the lack of wonders that his camera crew would wind up documenting in one of the most boring documentary series of the 21st Century.
By contrast, as we know, there was plenty of development in East Asia and Europe, especially Northwestern Europe:
As Staffan put it, “we can’t adjust for their entire history.”
In any case, this recent nonsense idea of Chisala, aside from running afoul Occam’s Razor, is his attempt to undercut the rebuttal to the deprivation argument. That is, it is a common argument of blank slatists that poverty and other forms of deprivation are responsible for differences in average IQ and national performance. Aside from emptiness of the whole deprivation argument, as noted above, there is the fact (as pointed out by me in Welcome Readers from Portugal!) that outliers to this pattern of deprivation and IQ all perform in accordance to their measured IQ, not according to their level of deprivation. Poor rural Chinese perform nearly as well in IQ and scholastically as the other East Asian societies do. Citizens in wealthy Arab oil states perform as badly as those in poorer ones which lack oil. I’m sure Chisala doesn’t like this particular uncomfortable fact, so I suspect he concocted his feeble theory in part to try to nullify this unwelcome reality.
And finally, there is the fundamental problem that Chisala doesn’t understand either evolution or the formula that guides it, the breeder’ s equation. There is no reason to suspect that human groups that have been separated for tens of thousands of years in vastly different environments would be the same in all their cognitive and behavioral qualities. In fact, a priori we should expect them not to be, since such equivalence after so many generations of separate evolution is nigh impossible.
I expected most of this to be obvious, which is why I haven’t paid too much attention to Chisala’s posts. But, I may have overestimated both his impact and people’s ability to spot the obvious, hence, this writing.
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