IQ Population Genetics - Not So Simple

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Updated September 23:

IQ Population Genetics: It’s Not as Simple as You Think. That's the title of a very nice paper by Gerhard Gerhard Meisenberg, a professor at Ross University, in the Caribbean nation of Dominica. Meisenberg previously worked on a study in Dominica that found a massive 18-point IQ increase over 35 years on this small, almost all-Black island. It was published in the Winter 2003 issue of the Mankind Quarterly.

I believe that the Mankind Quarterly is run by the nefarious Richard Lynn, but in between the racist horrors, there is a lot of great academic work in there that you often can't find in other places. Meisenberg in particular is an interesting scholar, fully open to genes for intelligence that vary by race but also a strong proponent of the Flynn Effect of strong environmental effects on IQ.

First of all, Meisenberg notes that IQ correlates fairly well with race, religion latitude and economic development. Other variables such as head size, type of economic system and history of colonialism do not seem to have much of an effect.

Most of the text is about IQ and genes, which I am not much interested in.

He does, however, uphold the supposed "Lewontin's Fallacy", which hereditarians love to thrash.

First of all, Luigi Cavalli-Sforza has proven that 85% of genetic differences between humans is within races, 10% between races and 5% between ethnic groups within races. What is interesting is that Arthur Jensen, uber-IQ hereditarian, agrees with this assessment. He found that 15% of IQ variation in humans in his studies was between races. But this added up to a significant figure.

Skull shape has similar figures: 79% between individuals, 13% between races and 6% between ethnic groups within races.

So for genes, skull shape and intelligence, Lewontin's analogy makes sense, and there is no need to conjure up "fallacies" about it. In terms of intelligence, Lewontin's analogy ends up showing a significant Black-White differential.

In contrast, skin color is almost totally racial: 88% is between races, 3% is among ethnic groups in races and 9% is between individuals. There was very strong selection pressure for skin color due to the needs for Vitamin D and protection from UV waves - skull shape underwent no such rigorous selection.

This paper shows a substantial increase in the size of cranial vaults in the US from 1850-1975. The probable cause is general nutrition. Although the Flynn Effect has been ridiculed on the basis that we could not possibly be smarter than our grandparents' generation, if our brains are bigger than theirs were, it makes sense that we could actually be smarter than previous generations.

The head size increase was consistent in both Blacks and Whites and males and females. This gives the lie to the hereditarian notion that the Black IQ has been a flat "85" for the last 100 years. Clearly, Blacks today have much larger heads and are much brighter than Blacks a century ago. Black skulls showed no change from 1850-1900, but after 1900, their size began expanding dramatically, an increase that is ongoing.

In particular and amazingly, Whites and Blacks in the late 1900's had skulls that were closer to each other than either was to their ancestors! Especially, US Black skulls are now dramatically different from African skulls.

This study looked at Black and White skulls in the US through time. Colonial Black skulls looked very African. By 1900, they looked less African, though still retaining strong African characteristics. In both races, there has been a trend towards decreased prognathism and a receding lower half of the face.

Meisenberg also questions whether or not IQ actually drives economic development. If so, then why did the Industrial Revolution take place in Europe rather than in Northeast Asia? He questions the notion that genetic IQ differentials among races take thousands of years, shedding doubt on Lynn's Ice Age Theory. Meisenberg suggests that the Asian advantage over Whites in IQ may have evolved in only the past 200 years or so.

There are problems with the latitude effect on IQ as a variable. For one, it has no effect among Africans. It seems to have had little effect in Amerindians either. Latitude also correlates with brain size and Meisenberg gives us the first data I have seen on head size in SE Asians. Malays have quite small heads and IQ's of 92, whereas Koreans have much larger heads and IQ's of 106.

Meisenberg also suggests that genetic intelligence and head size rises may work much faster than skin color changes due to complexity of the traits. Intelligence is probably acted on by many genes, whereas skin color is only controlled by a small set of genes. The greater the number of genes controlling an effect, the faster evolution can occur.

Meisenberg comes out strongly for a high standard of living as having a positive effect on IQ.

The massive rise of IQ that took place in many countries over the past century shows conclusively that environmental effects can have a powerful effect on the average intellectual level of large populations. Presumably one or another aspect of “standard of living” is responsible for this secular trend: education, nutrition, health care, mass media, or, most likely, a combination of all of these.

Together with the Flynn effect, these results suggest that the causal arrow points both ways. High intelligence produces a high standard of living, which in turn raises intelligence even more. Thus intelligence and economic development are mutually reinforcing in a positive feedback loop.

This feedback loop explains two of the greatest mysteries of our time: the rapid progress of science, technology and economic development during the 20th century, which is indeed a major historical anomaly; and the rise in mental test performance that has become known as the Flynn effect.

This feedback loop between intelligence and standard of living can explain the great magnitude of the IQ differences between nations.

It predicts that even in cases where genetic differences affecting mental ability are small, the observed phenotypic differences become amplified because the slightly more gifted populations achieve a higher standard of living which raises their measured intelligence even more, which in turn raises their standard of living yet further. Similar “amplifier effects” have previously been proposed as explanations for the Flynn effect.

Excellent stuff, huh?

First of all, let us elucidate who exactly those opposing the Flynn Effect so strenuously are. Other than hereditarians like Jensen with a deep career and theoretical investment in hereditarian views, the most vociferous opponents are almost all Whites, mostly Northern Europeans, creepily enough (Aryans anyone?). Almost all of them are racists.

Even Southern European White nationalist types tend to poo-poo IQ fetishism more than the de facto Nordicists.

Race realists seem more interested in the Flynn Effect. An environmental effect on IQ will mean that differences between races are not fixed by the genes, and these racists have a strong need to believe that Blacks, Hispanics, Amerindians, etc. are hereditarily inferior to European Whites in intelligence, and that no cultural variables can change this.

If environment effects IQ, then presumably Blacks or others could start to close the gap with Whites, and they want to maintain their superior position.

One of the principal arguments against the Flynn Effect is that we have not seen the expected Second Renaissance in the arts, sciences, etc. that we should have seen. Nor should we be seeing people railing about school failure and the ignorance of high school and college students. But these criticisms fail to understand the Flynn Effect.

The effect has been mostly on culture-free areas like abstract thinking, and much less to none on areas effected by schooling such as mathematics, vocabulary and general knowledge.

With school learning skills flat and many more poor students staying in high school and even trying to go college (students who would have dropped out of high school or never gone to college in my Mother's generation), we should expect disconnects between expectations and scores.

On the other hand, Meisenberg suggests that the supposedly nonexistent Renaissance has in fact occurred. As he notes, the rapid progress of science, technology and economic development in the 20th century is historically anomalous. I would argue that it was a Renaissance, and would add that it took place in the arts also. Look at the explosion of creativity in literature, music, art and architecture in the 20th Century.

And he notes that this explosion in intellectual and societal development nicely mirrored a concomitant rise in both intelligence as measured by IQ and head size.

Further, the deniers of the Flynn Effect have a hard time explaining away the growth in head size in the last 150 years, which eerily parallels the Flynn Effect. If the Flynn Effect represents no real increase in intelligence, as the hereditarians insist, why did it parallel both a major technological and intellectual revolution and a striking increase in head size itself?

These scores are taken from this paper, and indicate varying scores for IQ tests and semi-IQ tests taken over about 30 years. As you move down in each individual row, you move into revised versions of the tests in more recent years.

As you can see, White adult IQ (age 25+) in the US is now 102.9, or 103 rounded off. Black adult IQ (age 25+) has increased in recent years to 89.1 or 89 rounded off. There remains a 13.8 point gap between Blacks and Whites. It is no longer appropriate to say that Blacks have an IQ of 85.

A Flynn Effect and growth of US Black skull size explain nicely the relatively high IQ's of US Blacks. By White percentages alone, US Blacks should have IQ's of only 72 (native IQ of 67 plus 17.5% White IQ of 103 gives 67 + 5 = 72). With Black adult IQ (age 25+) in the US now at 89.1, that leaves 15.1 points of US Black IQ unexplained. Meisenberg's theories laid out in this paper explain this well.

At the same time, there have been similar rises in IQ for immigrants from East India and the Caribbean to the UK and for North Africans to the Europe. Hereditarians such as Richard Lynn desperately try to explain these increases away as either selective immigration or increased miscegenation among UK Jamaicans, but given the parallel experiences of US Blacks, it seems we are dealing with a Flynn Effect in Europe also.

Meisenberg has an interesting take on contraception. In terms of selection for intelligence, widespread contraception use is dysgenic in advanced societies and eugenic in developing countries. Over time, population differences in IQ should narrow, something we socialists like.

References

Beals, K.L., Smith, C.L. & Dodd, S.M. 1984. Brain Size, Cranial Morphology, Climate, And Time Machines. Current Anthropology, 25:301-330.

Dickens, William T. & Flynn, James R. October 2006. Black Americans Reduce the Racial IQ Gap: Evidence from Standardization Samples. Psychological Science.

Jantz, RL. July 2001. Cranial change in Americans: 1850-1975. J Forensic Sci. 46(4):784-7.

Meisenberg, Gerhard. Winter 2003. IQ Population Genetics: It’s Not as Simple as You Think. Washington, DC: Mankind Quarterly, Volume XLIV, Number 2, pp. 185-210.

Truesdell, Nicole D. May 2005. Secular Change In The Skull Between American Blacks And Whites. MA Thesis. Baton Rogue, LA: Louisiana State University and Agricultural and Mechanical College, Department of Geography and Anthropology.

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