Category: IQ and Heredity

Five Minds for the Future by Howard Gardner, 2007

Howard Gardner and his team of researchers/propagandists have been pushing the theory of “multiple intelligences” since 1983, without empirical data. They rely on anecdotal stories to show that all humans are equally intelligent—they just have different intelligences that each person has compared to others. The primary purpose of this program is to try and provide an alternative explanation for what constitutes intelligence, so that Jensenism/Spearman’s g can be undermined as the only empirical program that has any real validity. (See Wikipedia for a good explanation of the “MI” theory and its failures.)

When I ordered the above book by Gardner, I thought it would be expanding on his primary work on multiple intelligences. Instead, “The five minds posited in this book are different from the eight or nine human intelligences. Rather than being distinct computational capabilities, they are better thought of as broad uses of the mind that we can cultivate at school, in professions, or at the workplace.” The only thing I got out of the book was how muddled Gardner’s thinking is with regards to human biology, so I’ll elaborate on just a few anomalies I found.

Gardner admits that, “We now have well-developed, empirically based theories of intelligence, problem solving, and creativity—along with the tools, software, and hardware based (or purportedly based) on these scientific advances.” Yet his whole program is based on undermining those very empirically based theories. His multiple intelligences program is primarily used within the educational community as an excuse for racial differences in intelligence. With this book, he tries to lay out ways of advancing or programming children in such a way that they will exhibit these five traits or abilities: “discipline”, the ability to “synthesize”, “creativity”, “respect” for others, and “ethical” behavior.

Continued...

Pseudoscience of Intelligent Design is similar to the assumption of racial equality.

One of the most perplexing dilemmas for me is trying to come up with mechanisms, articles, programs, etc. that could open up a true debate on the heritability of intelligence. Since The Bell Curve, all of the empirical data has supported Jensenism/hereditarianism while the equalitarian/naïve environmentalists have taken up the defensive position of attacking Jensenists (primarily their motives), while providing no alternative explanations for the persistence of the IQ-gap in average intelligence between different races.

In reading Michael Shermer’s book Why Darwin Matters: The Case Against Intelligent Design (2006), many of the arguments put forth by Intelligent Design advocates (Creationists) are reflective of the arguments used by equalitarians against Jensenists. What is interesting is that it is accepted that Creationism is pseudoscience and universally rejected in the biological sciences, while equalitarianism is still considered to be an alternative theory for explaining the differences in average intelligence between the races.

Continued...

James Watson rocks the IQ banana skin

On August 31st the Guardian ran an article full of fulsome praise about the Science Museum’s new director, Prof Chris Rapley, CBE:-

When he takes over as director of the Science Museum on Monday, friends of Dr Rapley say we can expect ... [a] bold approach to communicating science.  They describe an exceptionally driven man who is “totally fearless” and a risk taker with a “curious energy”.  Unlike many scientists who hide behind safe technical language and guarded caveats, Dr Rapley is not afraid to put his head above the parapet.  He talks in plain language and is prepared to lay the ramifications of the science on the line to public and politicians alike.

... His new boss at the Science Museum, Martin Earwicker, is also full of praise. “He’s someone who is very good at public debate on key scientific issues. He’s not afraid to express his opinions to get debate going. He’s a good communicator of science, very passionate about it, a good frontman and a good public leader,” he said.

Well, this fine straight-talker’s first test wasn’t long in coming:-

Fury at DNA pioneer’s theory: Africans are less intelligent than Westerners

Celebrated scientist attacked for race comments: “All our social policies are based on the fact that their intelligence is the same as ours - whereas all the testing says not really”

One of the world’s most eminent scientists was embroiled in an extraordinary row last night after he claimed that black people were less intelligent than white people and the idea that “equal powers of reason” were shared across racial groups was a delusion.

James Watson, a Nobel Prize winner for his part in the unravelling of DNA who now runs one of America’s leading scientific research institutions, drew widespread condemnation for comments he made ahead of his arrival in Britain today for a speaking tour at venues including the Science Museum in London.

The 79-year-old geneticist reopened the explosive debate about race and science in a newspaper interview in which he said Western policies towards African countries were wrongly based on an assumption that black people were as clever as their white counterparts when “testing” suggested the contrary. He claimed genes responsible for creating differences in human intelligence could be found within a decade.

... Dr Watson told The Sunday Times that he was “inherently gloomy about the prospect of Africa” because “all our social policies are based on the fact that their intelligence is the same as ours – whereas all the testing says not really”. He said there was a natural desire that all human beings should be equal but “people who have to deal with black employees find this not true”.

His views are also reflected in a book published next week, in which he writes: “There is no firm reason to anticipate that the intellectual capacities of peoples geographically separated in their evolution should prove to have evolved identically. Our wanting to reserve equal powers of reason as some universal heritage of humanity will not be enough to make it so.”

Continued...

Racial equality can no longer be defended.

Four books that I have read in the last month highlight the dilemma that the nature/nurture debate faces. I’ll discuss each one to show how politicized and confused the issue becomes when science clashes with universal egalitarianism.

Wrestling with Behavior Genetics: Science, Ethics, and Public Conversation, edited by Parens, Chapman & Press. 2006. This book has chapters written from different perspectives by different authors. Only one, Kenneth F. Schaffner, contributes without hesitation what is involved in genetic/environmental studies. He states, “As I mentioned a little earlier, some researchers think a good heritability-of-IQ estimate for ‘the’ general, contemporary U.S. population is closer to 0.8 and others think it’s closer to 0.3 or 0.4. Matt McGue and colleagues, for example, examine much of the data collected during the twentieth century and conclude that by the time we are adults, about 80 percent of the variation with respect to IQ is due to genetic variation.”

Continued...

Smart fraction … less smart fraction … dumb fraction

La Griffe could have told them.  So, doubtless, could messers Rushton and Jensen.

From the Independent:-

White students do ‘better’

Black and Chinese students are less likely to get top university degrees than their white contemporaries, a government report has found.

The study suggested that ethnic minority undergraduates faced “a considerable cost” as a result because students who get first-class degrees increasingly command higher salaries.

... The gap was widest for black Caribbean, black African and Chinese students.  The analysis took account of factors such as gender, prior academic performance, subject studied and deprivation levels.

The study sample was huge: 65,000.  One would, of course, expect that as a fraction of their respective populations Chinese participation in higher education would surpass whites.  But one would also expect that Gauss would get ‘em in the end, and the best degrees will go where the right-hand curve is longest.

However, this being a government study I doubt that Jews were eliminated from the “white” contingent.  Also, South Asians weren’t mentioned at all - perhaps because on average Pakistani students could be expected to weight SA results downward, and the distribution was, therefore, unremarkably general.

I must admit to being puzzled by the report’s finding that women out-perform men, though.  That is calling Gauss a thorough-going liar, so what’s at work here?

Blind Faith in the Equality of Races

The most rational of scientists can fall into pseudoscience when their personal bias is allowed to take over. The book “Blind Faith: The Unholy Alliance of Religion and Medicine”, by Richard P. Sloan (2006) is such a book. Sloan defines what science is and how it is practiced, and then goes on to show how those who try to connect religion with healing in medicine have been very loose with the scientific facts. The book is excellent except when he takes several jabs at eugenics and intelligence, where his egalitarianism overpowers his science.

He has compiled a lot of data about science and its fundamentals. For example he states, “[from a 2005 Gallup poll], 75 percent of those polled believed in at least one of ten common pseudoscientific phenomena, while only 27 percent believed in none at all. Other polling data show similar findings.” I find this fascinating, because along with increasing a population’s intelligence, we must also improve rational thought. Perhaps, forming a eugenic group based partially on testing for not holding any pseudoscientific convictions, would be one way of bringing about rationality (see my review of ”The Robot’s Rebellion”).

Continued...

Book review of “Breeding between the Lines” by Alon Ziv

This is a book review of “Breeding between the lines: Why interracial people are healthier and more attractive,” by Alon Ziv, 184 pp., Barricade Books, 2006, ISBN: 1569803064. My preliminary impression that the book most likely doesn’t have decent data in it is confirmed.

Continued...

Strange new IQ study

We read:

“Girls have big advantage over boys on timed tests

“Vanderbilt University researchers Stephen Camarata and Richard Woodcock discovered that females have a significant advantage over males on timed tests and tasks. Camarata and Woodcock found the differences were particularly significant among pre-teens and teens....

Though males and females showed similar processing speed in kindergarten and pre-school, females became much more efficient than males in elementary, middle and high school.” The researchers found that males scored lower than females in all age groups in tests measuring processing speed, with the greatest discrepancy found among adolescents. However, the study also found that males consistently outperformed females in some verbal abilities, such as identifying objects, knowing antonyms and synonyms and completing verbal analogies…

The researchers found no significant overall intelligence differences between males and females in any age groups.  The research will be published in the May-June 2006 issue of the journal Intelligence. Camarata and Woodcock compiled their results through an evaluation of three sets of data collected from 1977 to 2001 as part of the Woodcock-Johnson Series of Cognitive and Achievement Tests.”

Source

Continued...

More on the physical basis of IQ

High IQ Kids Have Different Brain Growth Pattern: “The brains of high IQ children show a distinct pattern of development, according to a study from the National Institutes of Health (NIH) in Bethesda, Maryland.  The cortex, or outer mantle of the brain, starts out thinner and thickens more rapidly in very intelligent children, say the researchers. It then peaks at around 11 or 12 years old before thinning rapidly in the late teens. This developmental pattern, rather than sheer brain size, may have more to do with intelligence said Philip Shaw, lead author of the NIH study. He said the changes are subtle and what is driving them is a mystery. The scientists discovered the association between intelligence and brain development by taking MRI scans of 307 healthy children and teenagers, aged 5-19, over 2-year intervals as they grew up.

Even alkalinity differs:  “Researchers at England’s John Radcliffe Hospital, in Oxford, report that our brain’s pH--how acidic or alkaline it is--might be a clue to our intelligence.  Using a technique called magnetic resonance spectroscopy (MRS), researchers examined the brains of 42 British schoolboys. Just as its close cousin MRI creates vivid images of a person’s internal anatomy, MRS lets doctors study an organ’s chemistry. When the British scientists compared the lads’ IQ scores with their MRS results, they uncovered an intriguing relationship: the smarter the boy, the more alkaline his brain. Although the relationship between alkalinity and aptitude didn’t hold for every aspect of intelligence, verbal skills and reading comprehension seemed especially linked to pH, the Radcliffe team reports in the Proceedings of the Royal Society of London.

Sex and IQ

This looks like some independent confirmation that Richard Lynn is right and that the average IQ score for women is lower.  To get men and women showing up as scoring equally (on average), the test authors deducted points from the scores of men.

I have just posted here the original Lynn & Irwing paper.  The ferocity of the attack on the paper is exactly what we would expect of a genuine contribution to the advancement of knowledge.  Work that overturns what has long been believed will of course be resisted.  So to allow the general reader to see for himself/herself that the paper is utterly sound, I have reproduced it.  Out of respect for copyright, however, I have omitted the Tables and References (Essential to serious scholars).

Most readers of the paper will be amazed to recognize nothing in it that resembles what critics like Blinkhorn have said about it.  Those who know of the uneasy relationship that Leftists have with the truth will not be surprised, however.

Continued...

Frank Ellis

Both Chris Brand and I have recently put up elsewhere comments about the Frank Ellis case—where Leeds university students in the UK are trying to get one of the teachers there sacked for “racism”.  See here and here.

Students Attack Intelligent Inquiry

An excerpt from The Guardian:

“Students and lecturers are calling for a Leeds University don to be sacked after he said he supported a theory that black people were inferior to whites. In a row that has reignited the debate on the limits of freedom of speech, Frank Ellis, a lecturer in Russian and Slavonic studies, sparked anger after stating, in an interview with the university’s student newspaper, that he was an ‘unrepentant Powellite’ who thought that the BNP was ‘a bit too socialist’ for his liking.  Ellis said he supported right-wing ideas such as the Bell Curve theory, which held that white people were more intelligent than black people. ‘[It] has demonstrated to me beyond any reasonable doubt there is a persistent gap in average black and white average intelligence.’ ....  Now students are preparing to picket his lectures, protest on campus and bombard the vice-chancellor with emails calling for Ellis to be removed from his post.”

Source

Statements such as those made by Ellis have been normal among psychometricians (specialists in psychological measurement) for nearly 100 years.  As most people reading here would know, you can find them summarized in the book Ellis refers to.  But making such statements in public always attracts wrath.  Ellis is one of those rare people who puts telling the truth as he sees it above his own self-interest.  It is heartening that his university is resisting the calls to sack him.  There would not be much left of academic freedom in Britain if they did sack him.

Those pesky genetics again

“Genetics can play a bigger role in determining a child’s reading ability than teaching, an Australian researcher says. An international study showed some children were born with “an unfortunate deal of the genetic deck” when it comes to reading skills, said study co-author Brian Byrne, professor of psychology at the University of New England in northern NSW.  No “magic bullet” of encouragement and tutoring would fully improve their reading abilities, he said.  Published in the latest issue of the British-based Journal of Research in Reading, the study showed the influence of parents reading to their children diminished significantly a year or so after they started school.  “The home environment doesn’t leave its mark much on children as they start to go through school, which is surprising to a lot of people,” Byrne said. “What seems to determine most of the differences amongst children, just in the normal school setting in terms of their reading skills, are genetics.”

More here. 

[Anybody who knows the high correlation between IQ and early reading ability will of course not be at all surprised by the finding]

Chris Brand comments on the finding too

Rural IQ Higher When US IQ Data Controlled for Black Presence

There is data on IQ by State for the United States from 1965.  Supporting the belief of many, the correlation is indeed negative between IQ and rural population (1990 census), r=-.24 N=47, and is almost significant at p=1/21.  However, if one excludes the States with the highest number of blacks per capita, (basically the Confederacy), the correlation reverses to r=.25 N=36, and isn’t quite as significant at p=1/14 (which is to be expected when you reduce N).  As might be expected, the correlation between IQ and blacks per capita is very and significantly negative, r=-.58, N=47 and p=1/85,844.  The 5 highest IQ States as of 1965 were, in order, Montana, New Hampshire, Connecticut, Idaho, Nevada.  Nevada would have been significantly more rural in 1965 as Las Vegas is among the fastest growing areas of the US, so I suspect 1965 census data would yield a more significant and higher correlation between rural white population and IQ.

Continued...

Rural IQ

It seems to be just about universal that rural populations test out with lower average IQs.  And popular culture recognizes that with words like “hick”, “yokel” and “bumpkin” being used to characterize rural dwellers.  So I am in no doubt that the phenomenon is real.  The only interesting question is:  Why?

The usual (and grossly insulting) explanation that I hear is that smart people migrate to the city, leaving the drooling idiots behind.  That implies a selective pressure that should give us a rural population that is of GENETICALLY lower intelligence.  An alternative explanation however is that country life is dull when compared to the big city and that a less stimulating environment in early childhood leads to the brain not reaching its genetic potential in at least those ways that are irrelevant to rural life.  It has long been claimed that lots of stimulation is needed in early childhood for the brain to undergo maximum development but the existence of some discordant studies leads me to what should be the obvious conclusion—that the disadvantage is not an overall one but rather a disadvantage when it comes to typically urban tasks (such as IQ tests).  And in some rural tasks (such as marksmanship) I would expect rural populations to do better.  The Flynn effect (rising average IQ) is sometimes tied to the widespread presence of TV in modern homes—with the stream of visual and auditory diversity (if I can use that word) that TV provides.  I myself have argued that improvements in perinatal care are the main driver of the Flynn effect but there is undoubtedly evidence for some educational value of TV and it clearly has some potential to “equalize” rural and urban environments.

So how do we decide?  Which explanation for the lower IQ is correct?  Are both of them correct?  I think the case of the Afrikaners is enlightening.  Up until recently they were a mainly rural population and they do test out well below the European norm (I forget the figure and am too lazy to look it up).  So are the Afrikaners genetically disadvantaged?  Most Anglo-South Africans would cheerfully assert that they are and would have a fund of Van der Merwe jokes that parallel American redneck jokes.  But that is just ethnic rivalry.  The two groups did have a rather nasty war, just over 100 years ago, you might remember.  Afrikaners certainly remember.

On my two trips to South Africa I stayed on both occasions with Afrikaners and in moving about the country I had plenty of opportunity to observe Afrikaners too.  And the idea that they are genetically inferior really is risible.  They are just the same efficient, orderly, capable, meticulous, energetic people as Dutchmen from the Netherlands.  They are exactly what their Northern European (mainly Dutch) ancestry would lead one to expect. 

And that was evident long ago.  During the utterly disgraceful war of Imperialist aggression, the British had roughly as many troops in South Africa as the USA had in Vietnam and yet a relative handful of Boers (Dutch farmers) held them off for years (with their good marksmanship being a definite factor in that) and would have held them off indefinitely if the British had not started killing their women and children in droves.  At that point of course the Boers gave in.  And if you think that a military resistence of that effectiveness is compatible with a low IQ, you know nothing of warfare.  The rural “gooks” of Vietnam did pretty well too, of course, though they needed the US Congress to help them win.

So that is why I think that the low IQ of rural populations everywhere (including India) does not necessarily indicate genetic disadvantage.

Performance IQ

Steve Sailer has a post up linking to a very interesting Slate piece about IQ and its correlation with performance:

http://isteve.blogspot.com/2006/01/slate-almost-mentions-dread-letters-iq.html

What’s interesting to me is that it shows - in no uncertain terms - the link between the two, in mission-critical terms.

Update:

Kevin Drum sallied forth:
http://www.washingtonmonthly.com/archives/individual/2006_01/007973.php

“Stereotype Threat”

I commented fairly acerbically in April 2004 on the latest gambit among psychologists for explaining away low average black IQ and educational attainment.  It is the “stereotype threat” theory.  The theory seems to have a number of incarnations but at its wackiest, it says that blacks do poorly because they are afraid of letting down their race!  Nonsense as gross as that hardly needs comment but let me simply ask:  If such fears exist at all, why do they not make the student try harder and thus do better?

A somewhat more reasonable theory is that blacks “drop their bundle”:  They know that they are on average unlikely to do well so don’t really try to do well.  All the studies that I have heard of over the years tend to show, however, that blacks have unusually HIGH motivation in the testing situation—so that theory need not detain us.

In that situation, psychologists have had to devise ever more dubious experiments to support their ideas.  The latest appears to be a study reported here of which we read: “In their spring study of 81 students at Boca Ciega High School in Gulfport, Brett Jones and Tom Kellow investigated “stereotype threat,” a phenomenon in which students worry their failure might confirm a negative belief about their race’.

Continued...

Hispanic IQ

I recently had an email discussion with Steve Sailer on the topic of Hispanic IQ which I reproduce here

Xmas Science Shocker! Startling New Study: IQ, Brain Size Correlated!

Didn’t see this one coming. Looks like I’ll have to develop a new Weltansicht.

Canadian researchers examined the brains of 100 people who were given extensive IQ tests before they died and found a correlation between cerebral volume and intelligence.

Story.

Background on Volkmar Weiss

A German reader has emailed me as follows:

Volkmar Weiss is a German scientist, living and working in Leipzig in East Germany, born 1944. He is one of the very few scientists here involved in research about the heritability of intelligence. I don’t know in how far Weiss was involved, but the former “German Democratic Republic” had an active demographic policy, enouraging marriage and childbearing in general and especially among academics. Thus, the GDR was able to raise the mean IQ of the population from 100 to 103, writes Weiss in his very good book “Die IQ-Falle” ("The IQ Trap").

Weiss has an interesting alternative theory about the heritability of intelligence, his research shows not only one, but three overlapping bell curves, one big with a median of 94, a smaller one with a median of 112, and an even smaller one with a median at 130.  Weiss developes an interesting social theory about the meaning of his findings - according to him, only very few genes are involved, and the “triple bell curve” makes sure there is always a “revolutionary” elite in waiting.

An interesting email from Volkmar Weiss in Leipzig

Today, encouraged by the discovery of the major genetic background of skin color of the white race, see http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=16357253&itool=iconabstr&query_hl=2 by using HapMap data, see http://www.hapmap.org , I had the idea to apply the same approach to IQ.  If the data of a century of IQ testing are not complete nonsense - see e.g. http://www.vdare.com/misc/051207_rushton_fallacy.htm and http://www.volkmar-weiss.de/table.html for further data and links - there should be a striking difference in allele frequencies between Eurasians on the one hand and Blacks of the other.

At our current state of knowledge, the genes DCDC2 and NQO2 have the highest probability to be correlated with general intelligence (IQ), see http://www.volkmar-weiss.de/intellig.html . Both genes have one common polymorphism, coding nonsynonymously. The allele frequency of the A allele rs2274305 of the dyslexia-gene DCDC2 is about 0.28 among Eurasians and 0.99 among Yorubas from Nigeria, about 0.80 among African Americans (known to be admixed with some white genes), see http://www.hapmap.org/cgi-perl/snp_details?name=rs2274305 . 

However, according to my data and theory, see http://www.volkmar-weiss.de/majgenes.html , a higher frequency of the rare allele among Eurasians should be correlated with a higher mean IQ of the population. Clearly, this is not the case with this SNP.  The frequency data of DCDC2rs2274305 contradict the major gene locus hypothesis. However, this SNP of DCDC2 could be of secondary importance to IQ. (Population data for the frequency of the deletion of DCDC2, said to be involved in reading ability, have not been published up to this day.)

NQO2 also has only one common polymorphism, coding nonsynonymously, namely rs2756081 (identical with rs1143684). 

The allele frequency of the C allele rs2756081 of NQO2 is about 0.25 among Eurasians (0.41 in Tokyo in a sample, which is not in Hardy-Weinberg equilibrium) and 0.00 among Yorubas from Nigeria, about 0.02 among African Americans, see http://www.hapmap.org/cgi-perl/snp_details?name=rs2756081 and http://www.ensembl.org/Homo_sapiens/snpview?snp=rs2756081 . These data are fitting perfectly. Could this already be the solution or could it be pure coincidence? At the moment, any direct evidence of a relationship between the genotypes of NQO2 and IQ is still lacking, for DCDC2 we have incomplete evidence.

If we align the genetic code of Homo sapiens and the chimpanzee, Pan troglodytes, in both species NQO2 is coded by 231 amino acids. However, at the position 47 of rs2756081, see http://www.ensembl.org/Homo_sapiens/alignview?class=Homology&gene=ENSG00000124588&g1=ENSPTRG00000017670&seq=Pep&format=mega , human Blacks are coding FF (phenylalanine) as chimps and a number of other mammals, and Eurasians with an above average IQ are coding LL or LL (leucine), below average FF.

If the necessary direct empirical evidence will be be found, it will be a shock for many. But scientists discover facts and do not create them. The bearer of the message is not its inventor. The society will have to face the truth.

I have already published this text on my homepage and posted to http://hum-molgen.org/bb/Forum9/HTML/000080.html . When we all will be a step further and wiser, it will be the accomplishment of thousands of research workers, and my personal merit will be a very small one and, I hope, will not perish uncited.

As I started 37 years ago to hit this target and to discover the genetic basement of social stratification (and not the differences between races), I was a very young man. 

Steve Pinker gives talk on the genetic intelligence of Jews.

http://www.seedmagazine.com/news/2005/12/jews_on_jews_jews_are_great.php
Jews on Jews: Jews are Great
Steven Pinker Discusses “Jews, Genes, & Intelligence” at the Center for
Jewish History.

by MAGGIE WITTLIN * Posted December 9, 2005 12:16 PM

Of the twelve billion people who have graced this earth, fewer than one hundred have earned the title of “Gentile Adored by My Jewish Grandmother.”

Mark Twain successfully infiltrated the order when he penned Concerning the Jews, an article discussing the intellectual prowess and survival skills of the Jewish people. The membership otherwise consists largely of Europeans who helped Jews during the Holocaust and political leaders who have gone out of their way to make peace with Israel.

Three University of Utah anthropologists have done their darndest to reach that rarified group close to my grandmother’s heart: Gregory Cochran, Jason Hardy and Henry Harpending collaborated on “The Natural History of Ashkenazi Intelligence,” a paper recently accepted for publication in the Journal of Biosocial Sciences. In the article, they unveil a theory for why Jews have an average IQ that’s one standard deviation above the European norm.

Continued...

Ecological correlations between IQ, skin color, temperature and GDP per capita

Here is some cool research that is about to be published in the journal Intelligence, though this research is unlikely to get a lot of press in the MSM.  The researchers (Donald Templer and Hiroko Arikawa) computed the correlations between the predominant skin color in 129 nations, GDP per capita, high and low mean temperatures in the summer and winter, and skin color.  The correlation between predominant skin color and population IQ was − 0.92!  The meat of the data is presented in the Table below. 

Continued...

Another biological influence at work

"Scientists have discovered why some shorter children do worse at school than taller youngsters.  A team from the University of Bristol found that children with lower levels of a height controlling hormone also had lower IQs. The study is the first to make a link between the insulin-like growth hormone and intelligence.  Professor David Gunnell and his colleagues measured levels of Insulin Growth Factor IGF-I in the blood of 547 children, who also took an intelligence test at the age of eight. When the researchers compared IGF-I levels in the youngsters in the study, they found a significant link between the growth hormone and intelligence. For every 100 nanograms per millilitre increase in IGF-I levels, the IQ increased by three points.

At the moment scientists do not know what happens in the body to link poor growth and impaired development in the brain. But one explanation could be that growth hormones also affect brain development. They said this effect seemed to be restricted to the verbal component of IQ, as the link was not seen in other tests ...  The study, part of the long-running Children of the 90s project, is published in Pediatrics”

More here

Top Ecological Correlations With IQ: -Blacks, +Nordics, -Binge Drinking

The top State-wide ecological correlations* with IQ are rather fascinating**.  Make of them what you will but here are the thoughts that occur to me.

Continued...