Race and IQ, con't.

More thoughts on Eric Turkheimer's research:

The more I think about it, the more convinced I am Turkheimer's work is one of the keys to unraveling the Race-IQ debate. His argument goes something like this:

Right now, there are two conflicting pieces of evidence, each of which is seized upon by each side in the debate. On the one hand, there are twin studies. You look at twins, raised in very different adoptive families, and you find that their IQs are very similar. That suggests IQ is largely heritable, and that environment plays only a modest role.

On the other hand, there are studies showing that if a child of a very poor family, adopted at birth into a wealthy family, will have a much higher IQ than his or her siblings, or his or her parents, who remain in poverty. 

This is, obviously, not a trivial disagreement. Someone like Charles Murray, who takes the former position, uses it as explanation for why he think social programs--like Head Start--are a waste of time and money. It is also why he thinks that the gap that presently exists between white and black average IQ scores will likely persist, regardless of what kind of steps we take as a society.  Liberals, meanwhile, use the latter evidence to justify the idea of an aggressive social policy.

So who's right? Turkkeimer would say, both sides are. 

He used a very large data set--the National Collaborative Perinatal Project--and found that the relationship between socio-economic status and IQ was non-linear. Children moving from poverty to the middle class see their IQ's jump: IQ at that end of the socio-economic scale is highly sensitive to environmental improvements. But the kinds of twins studies usually relied upon by IQ  fundamentalists and that yield such high genetic effects, are much more likely to involve comparisons among middle and upper middle class environments--and that end of the scale, Turkheimer's data suggests, environment doesn't play a big role. 

In other words, the lawyer who plays Mozart in the crib for his daughter, in order to raise her IQ, is wasting his time.  But dramatically increasing the educational resources available to inner city kids makes a  lot of sense.

This, I think, helps to clarify a lot of what drives so many of us crazy about Charles Murray and his ilk. We're not disputing the importance of IQ. And we're not disputing that genes play a huge role in determining IQ. We're just saying that it's hopelessly naive to assume that the same rules apply to suburban, middle-class whites as apply to, say, urban, inner-city black families.

Comments

[Ben Guest]

Malcolm,

I am disputing that genes play a huge role in IQ. In fact, I don't think they play any role. If IQ is genetic then it would be fixed at birth. Clearly it is not. There is a nice story about Michael Oher, a lineman at the University of Mississippi, in Michael Lewis' fantastic book The Blind Side. Oher grew up in extreme poverty in inner-city Memphis. Through several twists of fate he is adopted, as a teenager, by a rich, suburban family. His IQ is tested by the state before he is adopted and he comes out at 90 (by my recollection. I don't have the book in front of me so my numbers may be a little off.) He is tested again after living with this family that showers him with love and affection (and sends him to a private school). He scores 120 (or therabouts). A 30 point increase, when it is supposed to be a fixed score.

IQ is a test, one that can be prepped for, just like Kaplan did with the SAT (and which you wrote a nice article about in 2001). Another interesting point in your Kaplan article was about musical talent, and how there was no correlation between "natural ability" and performance. The best musicians were the ones who practiced the most.

Intelligence, musical ability, and all of the other talents that we mistake as natural are simply the result of practice, hard work, and support.

[Dane]

That's more like it.As a chinese who has "soaked my head" in confucian philosophy,I believe in GOLDEN MEAN,that is, every debate or argument,predicament, dilemma, or paradox has a middle ground yet to be reached.
This post of yours did a wonderful job doing that, very convincingly.

[Dane]

And your post also clarified and emphasized one thing: calibration.
Both on the "intelligence" tests we administer, and on the subjects we administer the IQ tests on,just to make sure we are actually measuring the similar group of people with an effective and the same(standardized) set of tests.

[Dane]

By the way, when will your latest book come out? and do you have plans to visit china on a book tour or lecture tour or sth?

[Cheryl's Place]

It seems to me many variables are at work in building one's IQ. Genetics, environment appear as the most obvious variables in the arguments to date. Neither fully explain the subject's passion and drive in life. I have seen many siblings in wealthy and poor environments end up on the opposite ends of the IQ spectrum. My observation suggests the difference between them is their passion for learning and their competitive spirit.

[Steve Sailer]

The problem with most adoption studies is finding people who were born into a higher class than they were adopted into. Fortunately, there is a a small (38 cases) but impressive French study by Capron and Duyme of the impact of adoption on IQ at age 14. This French effort put a lot of work into getting around the "restriction of range" problem (they seldom let people in the bottom ranks of society adopt children). They found 8 kids who were the biological children of professional class parents but were raised by farmers or laborers (they wanted 10, but could find only 8). And they found ten kids born at the bottom raised at the bottom, 10 born at the bottom and raised at the top, and 10 born at the top and raised at the top, for a total of 38.

The bottom-line looks roughly like:

Nature 60 - Nurture 40

This is a larger role for environment than several American adoption studies have found, but it shows a slightly _greater_ role for genes than the 50-50 split be genes and evironment that Arthur Jensen and J.P. Rushton argued for in the 2005 meta-analysis that so peeved critics of William Saletan.

Darth Quixote offers a thorough analysis of the French study at Gene Expression:

http://www.gnxp.com/blog/2006/06/french-cross-fostering-ado_115070325923398202.php

[SN]

@Ben Guest - I don't think it can be disputed that genes play some role in intelligence (whether you believe that intelligence can be quantified by an IQ test is another issue). Just because intelligence can change by doing certain things or by changes in environment doesn't mean there is no genetic component at all. For example, an apple tree is unlikely to grow as tall as a sequoia no matter how much care you take of it. Yet if you were to mistreat a sequoia there's every chance that you could prevent it from growing to the height it would have grown had you not mistreated it. Ok, maybe not the best analogy in the world but I believe we should think of genes as some sort of limit upon our capabilities with environment playing a major role in deciding how close to that limit we reach. Even hard work, perseverence etc. -- I wonder how much of that is hard-wired in us to begin with. I'm pretty sure that's an inheritable trait too, just like intelligence.

[Ben Guest]

SN,

What proof do you have that intelligence is inheritable?

[LemmusLemmus]

Ben Guest,

I am not SN, but all behavioural genetics studies that I am aware of, including the one cited in the post, suggest there is a genetic component to IQ, as measured by IQ tests. This is well known.

It seems that you are making a not untypical error by mistaking the statement "there is a genetic component to IQ" for "IQ is 100% genetically determined". The former is true, the latter is false.

If you are aware of a study showing zero genetic influence on IQ, please give a reference.

[Steve Sailer]

Malcolm:

Thanks for admitting that Charles Murray drives you "crazy."

You need to stop creating straw men and then trying to smear them. Murray, Rushton, Jensen, and Lynn all argue for environment playing a sizable role in influencing IQ. I believe all of these people have endorsed, for example, fortification of staple foods with crucial micronutrients such as iodine and iron to prevent medical syndromes that lower national average IQs in much of the Third World.

http://www.vdare.com/Sailer/national_iq.htm

The true fundamentalists, in reality, are found on the opposite side among the many who deny all genetic influence on IQ.

Your problem is that you assume:

- What the race realist scientists say is evil.

- Therefore, they are evil.

- Therefore, I am justified in treating them in an evil fashion by making up smears about them and distorting their actual positions.

You really need to grow up.

Murray and Jensen are not only two of the finest social scientists of our age, but two of the finest human beings. Imagine the strength of character it takes to follow the data wherever it leads, knowing that you will be libeled for your honesty by ignorant journalists, who will in turn be applauded by the multitudes.

[Chip Burkitt]

I understood Turkheimer to be arguing for a fairly complex interplay between genetics and environment. There are plenty of studies showing that young animals born into environments devoid of certain stimuli will fail to develop the neural paths needed to deal with such stimuli. It seemed to me that Turkheimer was suggesting that children raised in impoverished families were likely to miss much of the rich stimulation of children born into wealthy families. Their cognitive abilities grow stunted as a result. So making environmental changes for children born to impoverished parents has a large effect on IQ. Conversely, children born into middle class and wealthy families have a much richer environment for their cognitive development. As a result, the effects of genetics in such populations tend to show up more. The questions that need to be asked are: Do the genetic differences show up along racial lines when economic influences are controlled for? And are the genetic differences significant enough to be of concern?

[Matt]

If we stipulate that certain social programs are ineffective, it does not necessarily follow that environment is unimportant. It could mean that the influence of the home environment swamps the effect of programs outside the home.

[noahpoah]

Ben Guest: "I am disputing that genes play a huge role in IQ. In fact, I don't think they play any role. If IQ is genetic then it would be fixed at birth."

Me: This is a terrible 'argument' against a role for genes in IQ. 'Genetic' does not imply 'fixed at birth'. To cite the first two examples that came to mind, secondary sex characteristics and primary vs. secondary teeth.

[doublehelix]

Here's a tangential but important question IMHO: If the environment matters, why is the environment of low-income (or high income) people the way that it is?

Unless we begin to understand why poor people's environment is impoverished, then we will never escape the nature/nurture IQ debate. (and by impoverished, I mean low literacy, high dropout rates, high crime & unemployment, high rates of drug abuse and high rates of illegitimacy)

I believe that one's environment is largely-though not wholly-self-created. I believe that like IQ, there is a heritable component to one's environment (the "extended phenotype"-a la R. Dawkins). Therefore, barring extreme and probably unconstitutional intrusions into people's lives, I sincerely doubt that efforts to improve the environments of the poor will make any difference, since the environment is partly of one's own choosing.

[Steve Sailer]

DoubleHelix is correct about the semi-authoritarian implications of my friend Jim Flynn's work. Flynn and his research partner Bill Dickens have been rather vague about what they think would keep the white-African-American test scores from growing so sharply as children turn into young adults (where the gap remains today the traditional 16.7 points, according to Flynn's book).

The Flynn-Dickens theory is quite plausible: it fits with the findings that identical twins become _more_ identical in IQ scores as they age. They imply that for everybody else who isn't an identical twin, small genetic differences are multiplied by individuals choosing different environments for themselves (choices based in part on their genetic predilections) as they grow up and become increasingly autonomous. So, whites and Asians tend to end up choosing for themselves to live lives of more cognitive challenge than blacks and Hispanics choose for themselves, as seen in their varying (on average) tastes, for example, in consumption of music, movies, and books (if any).

But thinking about converting that theory into a plan of action raises disturbing questions, since it basically sounds like it's implying a Bill Cosby-type war on the damn hippity-hop yap music. In essence, Flynn's theory seems to imply a call for action to ban much of 21st Century African-American popular culture.

This does not seem likely to happen, to put it mildly, so, by Flynn's logic, a large chunk of the current IQ gap between adult blacks and adult whites is likely to be around for a long, long time.

[Chen]

Hello, dear Mr Gladwell!
I really appreciate your blog, and I've read The Tipping Point in Chinese edition, but I couldn't find Blink. Could you send me your Tipping Point and Blink? I really want to read the original text. not the text written by translators.
Thank you very much!
Best wishes!

[Ben Guest]

Noahpoah,

What do you mean by secondary sex characteristics and secondary teeth?

[Ben Guest]

Lemmus,

All of the studies you have looked at show a correlation between parents who have a high IQ and their children having a high IQ. This does not mean intelligence is (partly or all) genetic. There is simply a connection.

The burden of proof is on you. I don't have to prove a negative (that IQ is not genetic).

That being said, no scientist, to my knowledge, has discovered an "intelligence gene."

[albatross]

Ben,

Good rule of thumb: When you devolve into arguments about which side has the burden of proof, you don't have enough evidence to come to a conclusive answer. (Another way to say the same thing: When your conclusions are enormously sensitive to your priors, you don't have enough data.)

I recommend looking at the APA statement on _The Bell Curve_ to see the common opinion on these issues among people who think about intelligence testing and related issues for a living. Google for it. My understanding (this isn't my field, and I'm not at all well read in it) is that there's a lot of evidence for the heritability of intelligence (as measured approximately by IQ), based on looking at siblings, identical/fraternal twins, and parents and children separated at birth by adoption. I don't think anyone knows the mechanisms by which this works, just that identical twins' IQs have a better correlation than fraternal twins' IQs, even when they're separated at birth and raised apart. Similarly, adopted kids' IQs wind up more strongly correlated with their biological parents' and siblings' than with their adoptive parents' and siblings'.

[Christopher Horn]

Is it true, based on Mr. Sailer's earlier post, that his dispute with Mr. Gladwell can essentially be boiled down to the question of what to blame for the current (low-achieving) state of American urban black culture?

For it seems as though Sailer and Gladwell could at least agree that there is something wrong in the low income black communities in the US today, something to do with devaluing education, intellectual achievement, "demonizing" such achievement as "acting white", etc.

Where they might disagree is whether this is a cultural artifact (environment) or inherent (genes).

As an aside, without reciting chapter and verse, it seems odd that obviously bright and hardworking fellows like Mr. Sailer infer genetic underpinnings for observed phenomena that are, by definition, cultural, and thus almost certainly arising due to environmental factors...

A humorous example to illustrate the point: two years ago, Dallas Mavericks star Dirk Nowitzki faced the embarassing revelation that he sings a David Hasselhoff song at the free throw line.

Now, Mr. Nowitzki has good company among his German compatriots for enjoying the cheesy croonings of Mr. Hasselhoff. But surely no one would advance the point that liking cornball soft rock is a genetic trait of Germans, at least they wouldn't do so without tongue planted firmly in cheek, would they?

Isn't the obviously simpler explanation that the reason any particular German (e.g. Nowitzki) likes Hasselhoff is because the rest of his countrymen do, and Nowitzki et al are moved by a (genetic) desire to fit in, rather than a (genetic) desire to prefer bad adult contemporary music?

On a serious note, wouldn't the same conclusion apply to the problematic black communities, that the members therein have the desire to fit in, - *that* desire being genetic - but the circumstances they fit into being an accident of any number of environmental factors?

In this case there would be a genetic component, but not one that specifically maps on things like preferring broken communities or bad anthemic love songs.

(Hopefully)

[jl]

Ben Guest-

secondary sex characteristics (like breasts on women) and adult teeth do not appear at birth but their eventual development is nevertheless largely due to genes. Similarly, your IQ is not "fixed at birth", but this does mean that IQ is not determined by genes to some degree, because your brain keeps developing until you're 20 or so, in part thanks to your genes.

[Christopher Horn]

As I was concocting that lighthearted example of Hasselhoff in my prior post, it set my mind wandering, lured by my own long-ago memories of anthemic adult contemporary classics.

There was a time, friends, a time where yours truly might have drifted into imaginings of himself as Steve Perry, crooning Faithfully to a special lady surrounded by our 20,000 closest friends. Its even possible that I felt those sentiments with all the sincerity a person could muster. Then and there, that might have pretty much been the "real" me...

These days, the lady is long gone (whoever she was!) Journey is gone, for everyone except maybe the Sopranos. I can barely even imagine, as 'me today', what it was like to be 'me then', but for the random occasional bout of reverie. I am sure with a bit of reflection each person reading this will relate to their own version of this story.

My point: whatever drove me to be/feel that way, at that time, in that place, probably seemed to capture pretty completely who I was, at that time, but if it was driven by my genes (and not rather by my life circumstances) I am afraid I have seriously defective genes, since not a whit of that life circumstance applies to me today, and 99% of the time I am completely incapable of relating to "those times".

Might I be the first-ever living creature to experience a complete genetic mutation within a single lifetime?

Or is the expressed manifestation of our existence determined by our environment, of the time and place we happen to be in...?

[Steve Sailer]

The issue at hand for the last two months has been whether or not the firing fire and publicly condemnation of America's most prominent man of science, James Watson, for calling attention to the resilience and likely long-term endurance of the racial gaps in intelligence was justified.

Are the widespread claims in the media that Watson's contention is "Utterly unsupported by scientific evidence" true? Or was the hysterical reaction against Watson motivated by fear of the ever-increasing evidence that he is right?

First, the existence of differences among the races in average ability to solve logical problems is not disputed by anyone familiar with the science. The more difficult question, however, is what are the causes of those various gaps? Arthur Jensen and J. P. Rushton, for example, argued in a 2005 meta-analysis that half of the most closely studied gap, that of one standard deviation on average between American whites and American blacks, is caused by environmental differences while the other half is genetic in origin. The true "fundamentalists" respond in horror that it _must_ be _all_ environmental.

At present, most of the evidence points toward genes playing a partial role, but the evidence remains circumstantial, since we have only the earliest indications of which gene variants affect intelligence.

The crucial thing to keep in mind, as James Watson pointed out this year in the concluding pages of his autobiography "Avoid Boring People," echoing what Charles Murray wrote in 2003 in "Human Accomplishment," is that we'll have much more direct evidence one way or another from genome analyses (such as the current Hap Map project) in the fairly near future.

In the mean time, while the behavioral geneticists do their work, amateurs like Malcolm could perform a public service by helping ratchet down the anti-science mania on display during the extended "Two Minute Hate" directed at James Watson, along with the earlier ones directed at Larry Summers, Charles Murray, Arthur Jensen, and so forth. Whatever the scientists find out, we're going to have to live with. Journalists and intellectuals should be preparing the public for the possibility that the genetic discoveries of the next decade or two will demonstrate that part of the gap is hereditary. Unfortunately, most of the punditocracy seems to want to argue that anybody who evaluates the data in a non-politically correct fashion is some kind of Nazi.

But what then happens when the data become, as is likely, overwhelming? Does that mean the Nazis were right? Of course not, but that's the logic of the current conventional wisdom, as propounded by Malcolm and so many others.

Instead of calling for toleration and open-mindedness, Malcolm just added fuel to the auto-da-fe by making up a new smear against Murray out of whole cloth, saying that Murray wants to throw low-IQ people in concentration camps, requiring Malcolm's editor at The New Yorker to publish a humiliating correction.

[Christopher Horn]

Shoot, now I admit my interest has been piqued:

Suppose you invited Mr. Sailer and friends over to your house to watch the documentary "Woodstock". Would Mr. Sailer conclude that the reason the hippies were so virulently opposed to "The Man", so totally anti-establishment, was because they were genetically wired to be that way?

And if so, would that create an uncomfortable situation when after the documentary you watched something like A&E's "Biography", talking about how so many of those same folks themselves grew up in fact to become the Man, that 20 years later many of them WERE the Establishment?

Or what about all these ex-cons turned preachers, who at different junctures of their lives passionately sowed discord and then later passionately spread the Word of Christ?

Heck, what would he say about the endlessly political aisle-jumping Winston Churchill?

I don't know whether Mr. Sailer would say so, but when I think of the "genetic" side of this argument my mind inevitably gets to Ayn Rand, sooner or later. Rand of course belived that there were certain folks among us who were "genetically" superior (i.e. John Galt in Atlas Shrugged), and the rest of us buffoons should pretty much stay out of their way.

For Rand, at least, genetic superiority was highly correlated with being a leading industrialist. I suppose Rand would have been disappointed to discover (as investor guru William Bernstein has pointed out), that pretty much no prominent industrial family has retained its wealth beyond a few generations, save the Rockefellers. If the rest of them did have superior genes, they apparently didn't do a great job of protecting their genetic stock.

What about today's industrialists, today's John Galts...how are their descendents doing?

[burger flipper]

Sailer, I think if your motives were pure you wouldn't need to post 12 times and include lines in each intended to poke at Gladwell. I also put little stock in your crowning "two of the finest human beings" of this age based on their performing their specified job duties.

As I said over on the Revolution, I doubt you had to wait for an RSS feed on the first Gladwell IQ post, I imagine you awoke with a start, bolt upright in bed, only a fleeting memory of the dream in which you secured the Superbowl win by chasing down Gladwell on a breakaway run.

That said, it's pretty obvious Gladwell has some pretty strong preconceived notions working here too, if not an agenda, a la Sailer.

And his interactions are often hard to stomach, whether it's the sycophantic 69 with the Sports Guy at ESPN or watching him flail around out of his depth with Megan McArdle.

But if you really wanted to make serious points Sailer, you might follow her example and present your case without using a pointed stick.