[tt] Slate: William Saletan: Created Equal: Race, genes, and intelligence.

[Premise Checker]

This is the most balanced discussion in MSM I have ever seen. Not much 
discussion of whether transhumanist developments are likely to increase or 
decrease these differences.

William Saletan: Created Equal: Race, genes, and intelligence.
http://www.slate.com/toolbar.aspx?action=print&id=2178122

  ______________________________________________________________

From: William Saletan
Subject: Liberal Creationism
Posted Sunday, Nov. 18, 2007, at 7:57 AM ET
  ______________________________________________________________

We hold these truths to be self-evident, that all men are created
equal, that they are endowed by their Creator with certain
unalienable Rights ...

--[1]Declaration of Independence

Last month, James Watson, the legendary biologist, was condemned
and forced into [2]retirement after claiming that African
intelligence wasn't "[3]the same as ours." "Racist, vicious and
[4]unsupported by science," said the Federation of American
Scientists. "[5]Utterly unsupported by scientific evidence,"
declared the U.S. government's supervisor of genetic research. The
New York Times told readers that when Watson implied "that black
Africans are less intelligent than whites, he [6]hadn't a
scientific leg to stand on."

I wish these assurances were true. [7]They aren't. Tests do show an
IQ deficit, not just for Africans relative to Europeans, but for
Europeans relative to Asians. Economic and cultural theories have
failed to explain most of the pattern, and there's strong
preliminary evidence that part of it is genetic. It's time to
prepare for the possibility that equality of intelligence, in the
sense of racial averages on tests, will turn out not to be true.

If this suggestion makes you angry--if you find the idea of genetic
racial advantages outrageous, socially corrosive, and
unthinkable--you're not the first to feel that way. Many Christians
are going through a similar struggle over evolution. Their faith in
human dignity rests on a literal belief in Genesis. To them,
evolution isn't just another fact; it's a threat to their whole
value system. As William Jennings Bryan [8]put it during the Scopes
trial, evolution meant elevating "supposedly superior intellects,"
"eliminating the weak," "paralyzing the hope of reform,"
jeopardizing "the doctrine of brotherhood," and undermining "the
sympathetic activities of a civilized society."

The same values--equality, hope, and brotherhood--are under
scientific threat today. But this time, the threat is racial
genetics, and the people struggling with it are liberals.

Evolution forced Christians to bend or break. They could insist on
the Bible's literal truth and deny the facts, as Bryan did. Or they
could seek a subtler account of creation and human dignity. Today,
the dilemma is yours. You can try to reconcile evidence of racial
differences with a more sophisticated understanding of equality and
opportunity. Or you can fight the evidence and hope it doesn't
break your faith.

I'm for reconciliation. Later this week, I'll make that case. But
if you choose to fight the evidence, [9]here's what you're up
against. Among white Americans, the average IQ, as of a decade or
so ago, was 103. Among Asian-Americans, it was 106. Among Jewish
Americans, it was 113. Among Latino Americans, it was 89. Among
African-Americans, it was 85. Around the world, studies find the
same general pattern: whites 100, East Asians 106, sub-Sarahan
Africans 70. One IQ table shows 113 in Hong Kong, 110 in Japan, and
100 in Britain. White populations in Australia, Canada, Europe, New
Zealand, South Africa, and the United States score closer to one
another than to the worldwide black average. It's been that way for
at least a century.

Remember, these are averages, and all groups overlap. You can't
deduce an individual's intelligence from her ethnicity. The only
thing you can reasonably infer is that anyone who presumes to rate
your IQ based on the color of your skin is probably dumber than you
are.

So, what should we make of the difference in averages?

We don't like to think IQ is mostly inherited. But we've all known
families who are smarter than others. Twin and sibling studies,
which can sort genetic from environmental factors, suggest more
than half the variation in IQ scores is genetic. A task force
report from the [10]American Psychological Association indicates it
might be even higher. The report doesn't conclude that genes
explain racial gaps in IQ. But the tests on which racial gaps are
biggest happen to be the tests on which genes, as measured by
comparative sibling performance, exert the biggest influence.

How could genes cause an IQ advantage? The simplest pathway is head
size. I thought head measurement had been discredited as
Eurocentric pseudoscience. I was wrong. In fact, it's been
[11]bolstered by MRI. On average, Asian-American kids have bigger
brains than white American kids, who in turn have bigger brains
than black American kids. This is true even though the order of
body size and weight runs in the other direction. The pattern holds
true throughout the world and persists at death, as measured by
brain weight.

According to twin studies, 50 percent to 90 percent of variation in
head size and brain volume is genetic. And when it comes to IQ,
size matters. The old science of head measurements found a 20
percent correlation of head size with IQ. The new science of MRI
finds at least a 40 percent correlation of brain size with IQ. One
analysis calculates that brain size could easily account for five
points of the black-white IQ gap.

I know, it sounds crazy. But if you approach the data from other
directions, you get the same results. The more black and white
scores differ on a test, the more performance on that test
correlates with head size and "g," a measure of the test's emphasis
on general intelligence. You can debate the reality of g, but you
can't debate the reality of head size. And when you compare black
and white kids who score the same on IQ tests, their average
difference in head circumference is zero.

Scientists have already [12]identified genes that influence brain
size and vary by continent. Whether these play a role in racial IQ
gaps, [13]nobody knows. But we should [14]welcome this research,
because any genetic hypothesis about intelligence ought to be
clarified and tested.

Critics think IQ tests are relative--i.e., they measure fitness for
success in our society, not in other societies. "In a
hunter-gatherer society, IQ will still be important, but if a
hunter cannot shoot straight, IQ will not bring food to the table,"
[15]argues psychologist [16]Robert Sternberg. "In a warrior society
... physical prowess may be equally necessary to stay alive." It's
a good point, but it bolsters the case for a genetic theory. Nature
isn't stupid. If Africans, Asians, and Europeans evolved different
genes, the reason is that their respective genes were suited to
their respective environments.

In fact, there's a mountain of evidence that differential evolution
has left each population with a balance of traits that could be
advantageous or disadvantageous, depending on circumstances. The
[17]list of differences is long and intricate. On average, compared
with whites, blacks mature more quickly in the womb, are born
earlier, and develop teeth, strength, and dexterity earlier. They
sit, crawl, walk, and dress themselves earlier. They reach sexual
maturity faster, and they have better eyesight. On each of these
measures, East Asians lag whites and blacks. In exchange, East
Asians get longer lives and bigger brains.

How this happened isn't clear. Everyone agrees that the three
populations separated 40,000 to 100,000 years ago. Even [18]critics
of racial IQ genetics accept the idea that through natural
selection, environmental differences may have caused abilities such
as distance running to become more common in some populations than
in others. Possibly, genes for cognitive complexity became so
crucial in some places that nature favored them over genes for
developmental speed and vision. If so, fitness for today's world is
mostly dumb luck. If we lived in a savannah, kids programmed to
mature slowly and grow big brains would be toast. Instead, we live
in a world of zoos, supermarkets, pediatricians, pharmaceuticals,
and information technology. Genetic advantages, in other words, are
culturally created.

Not that that's much consolation if you're stuck in the 21^st
century with a low IQ. Tomorrow we'll look at some of the arguments
against the genetic theory.
  ______________________________________________________________

From: William Saletan
Subject: Environmental Impact
Posted Monday, Nov. 19, 2007, at 7:47 AM ET
  ______________________________________________________________

[19]Yesterday we looked at evidence for a genetic theory of racial
differences in IQ. Today let's look at some of the arguments
against it. Again, I'm drawing heavily on a recent [20]exchange of
[21]papers published [22]by the [23]American Psychological
[24]Association.

One objection is that IQ tests are racially [25]biased. This is
true in the broadest sense: On average, African and Asian kids have
different advantages, and IQ tests focus on the things at which
more Asian kids have the edge. But in the narrower sense of testing
abilities that pay off in the modern world, IQ tests do their job.
They accurately predict the outcomes of black and white kids at
finishing high school, staying employed, and avoiding poverty,
welfare, or jail. They also accurately predict grades and job
performance in modern Africa. The SAT, GRE, and tests in the
private sector and the armed forces corroborate the racial patterns
on IQ tests. Kids of different backgrounds find the same questions
easy or hard. Nor do tests always favor a country's ethnic
majority. In Malaysia, Chinese and Indian minorities outscore
Malays.

If the tests aren't racist, some critics argue, then society is.
That's true, in the sense that racism persists. But that alone
can't account for the patterns in IQ scores. Why do blacks in the
white-dominated United States score 15 points higher than blacks in
black-dominated African countries, including countries that have
been free of colonial rule for half a century? And why do
Asian-Americans outscore white Americans?

Another common critique is that race is a fuzzy concept. By various
estimates, 20 percent to 30 percent of the genes in "black"
Americans actually came from Europe. Again, it's a good point, but
it bolsters the case for a genetic explanation. Black Americans,
like "colored" South Africans, score halfway between South African
blacks and whites on IQ tests. The lowest black IQ averages in the
United States show up in the South, where the rate of genetic
blending is lowest. There's even some biological evidence: a
correlation between racial "admixture" and brain weight. Reading
about studies of "admixture" is pretty nauseating. But the nausea
doesn't make the studies go away.

My first reaction, looking at this pattern, was that if the
highest-scoring blacks are those who have lighter skin or live in
whiter countries, the reason must be their high socioeconomic
status relative to other blacks. But then you have to explain why,
on the SAT, white kids from households with annual incomes of
$20,000 to $30,000 easily outscore black kids from households with
annual incomes of $80,000 to $100,000. You also have to explain
why, on IQ tests, white kids of parents with low incomes and low
IQs outscore black kids of parents with high incomes and high IQs.
Or why Inuits and Native Americans outscore American blacks.

The current favorite alternative to a genetic explanation is that
black kids grow up in a less intellectually supportive culture.
This is a testament to how far the race discussion has shifted to
the right. Twenty years ago, conservatives were blaming culture,
while liberals blamed racism and poverty. Now liberals are blaming
culture because the emerging alternative, genetics, is even more
repellent.

The best way to assess the effects of culture and socioeconomic
status is to look at trans-racial adoptions, which combine one
race's genes with another's environment. Among Asian-American kids,
biological norms seem to prevail. In one study, kids adopted from
Southeast Asia, half of whom had been hospitalized for
malnutrition, outscored the U.S. IQ average by 20 points. In
another study, kids adopted from Korea outscored the U.S. average
by two to 12 points, depending on their degree of malnutrition. In
a third study, Korean kids adopted in Belgium outscored the Belgian
average by at least 10 points, regardless of their adoptive
parents' socioeconomic status.

Studies of African-American kids are less clear. One looked at
children adopted into white upper-middle class families in
Minnesota. The new environment apparently [26]helped: On average,
the kids exceeded the IQ norms for their respective populations.
However, it [27]didn't wipe out racial differences. Adopted kids
with two white biological parents slightly outscored kids with one
black biological parent, who in turn significantly outscored kids
with two black biological parents. The most plausible environmental
explanation for this discrepancy is that the half-black kids (in
terms of their number of black biological parents) were treated
better than the all-black kids. But the study shot down that
theory. Twelve of the half-black kids were mistakenly thought by
their adoptive parents to be all-black. That made no difference.
They scored as well as the other half-black kids.

In Germany, a study of kids fathered by foreign soldiers and raised
by German women found that kids with white biological dads scored
[28]the same as kids with biological dads of "African" origin.
Hereditarians (scholars who advocate genetic explanations) complain
that the sample was skewed because at least 20 percent of the
"African" dads were white North Africans. I find that complaint
pretty interesting, since it implies that North Africans are a lot
smarter than other "whites." Their better critique is that the pool
of blacks in the U.S. military had already been filtered by IQ
tests. Even environmentalists (scholars who advocate nongenetic
explanations) concede that this filter radically distorted the
numbers. But again, the complaint teaches a lesson: In any
nonrandom pool of people, you can't deduce even average IQ from
race.

[29]Other studies lend support to both sides. In one study,
half-black kids scored halfway between white and black kids, but
kids with white moms and black dads (biologically speaking) scored
nine points higher than kids with black moms and white dads. In
another study, black kids adopted into white middle-class families
scored 13 points higher than black kids adopted into black
middle-class families, and both groups outscored the white average.

Each camp points out flaws in the other's studies, and the debate
is far from over. But when you boil down the studies, they suggest
three patterns. One, better environments produce better results.
Two, moms appear to make a difference, environmentally and
biologically. (Their biological influence could be hormonal or
nutritional rather than genetic.) Three, underneath those factors,
a racial gap persists. One problem with most of the adoption
studies is that as a general rule, genetic differences in IQ tend
to firm up in adolescence. And in the only study that persisted to
that point (the one in Minnesota), kids scored on average according
to how many of their biological parents were black.

The best argument against genetics isn't in these studies. It's in
data that show [30]shrinkage of the black-white IQ gap over time.
>From these trends, environmentalists conclude that the gap is
closing to zero. Hereditarians read the data differently. They
agree that the gap closed fractionally in the middle decades of the
20^th century, but they argue that scores in the last two to three
decades [31]show no improvement.

I've been soaking my head in each side's computations and
arguments. They're incredibly technical. Basically, the debate over
the IQ surge is a lot like the debate over the Iraq troop surge,
except that the sides are reversed. Here, it's the liberals who are
betting on the surge, while the conservatives dismiss it as
illogical and doomed. On the one hand, the IQ surge is hugely
exciting. If it closes the gap to zero, it moots all the putative
evidence of genetic barriers to equality. On the other hand, the
case for it is as fragile as the case for the Iraq surge. You hope
it pans out, but you can't see why it would, given that none of the
complicating factors implied by previous data has been adequately
explained or taken into account. Furthermore, to construe
meaningful closure of the IQ gap in the last 20 years, you have to
do a lot of cherry-picking, inference, and projection. I have a
hard time explaining why I should go along with those tactics when
it comes to IQ but not when it comes to Iraq.

When I look at all the data, studies, and arguments, I see a prima
facie case for partial genetic influence. I don't see conclusive
evidence either way in the adoption studies. I don't see closure of
the racial IQ gap to single digits. And I see too much data that
can't be reconciled with the surge or explained by current
environmental theories. I hope the surge surprises me. But in case
it doesn't, I want to start thinking about how to be an egalitarian
in an age of genetic difference, even between races. More on that
tomorrow.
  ______________________________________________________________

From: William Saletan
Subject: All God's Children
Posted Tuesday, Nov. 20, 2007, at 7:54 AM ET
  ______________________________________________________________

Why write about this topic? Why hurt people's feelings? Why gratify
bigots?

Because truth matters. Because the truth isn't as bad as our
ignorant, half-formed fears and suspicions about it. And because
you can't solve a problem till you understand it.

[32]Two days ago, I said we could fight the evidence of racial
differences in IQ, or we could accept it. [33]Yesterday, I outlined
the difficulty of fighting it. What happens if we accept it? Can we
still believe in equality?

Let's look past our fears and caricatures and see what the evidence
actually teaches us.

1. Individual IQ can't be predicted from race. According to the
[34]data, at least 15 percent to 20 percent of black Americans
exceed the average IQ of white Americans. If you think it's safe to
guess that a white job applicant is smarter than a black one,
consider this: The most important job in the world is president of
the United States. Over the last seven years, the most important
judgment relevant to that job was whether to authorize, endorse, or
oppose the use of force in Iraq. Among the dozen viable candidates
who have applied for the job, one is black. Guess which one got it
right?

2. Subgroup IQ can't be predicted from race. Go back and look at
the [35]German study I mentioned yesterday. Kids fathered by black
soldiers scored the same as kids fathered by white soldiers. The
explanation offered by hereditarians was that blacks in the
military were screened for IQ, thereby wiping out the racial IQ
gap.

Think about that explanation. It undermines the claim, attributed
to James Watson by the Times of London, that "[36]people who have
to deal with black employees" find equality untrue. (The Times
purports to have Watson's interview on tape but hasn't published
the whole quote or responded to requests for it.) If employment
screens out lower IQs, you can't infer squat about black employees.
And that isn't the only confounding factor. Every time a study
highlights some group of blacks who score well, hereditarians argue
that the sample isn't random. That may be true, but it's also true
of the people you live next to, work with, and meet on the street.
Every black person in your office could have an IQ over 120.

3. Whitey does not come out on top. If you came here looking for
material for your Aryan supremacy Web site, sorry. Stratifying the
world by racial IQ will leave your volk in the dust. You might want
to think about marrying a nice Jewish girl from [37]Hong Kong. Or
maybe reconsider that whole stratification idea.

4. Racism is elitism minus information. No matter how crude race is
as a proxy for intelligence, some people will use it that way,
simply because they can see your skin but not your brain. What if
we cut out the middleman? What if, instead of keeping individual
IQs secret, we made them more transparent? If you don't accept IQ,
pick some other measure of intelligence. You may hate labeling or
"tracking" kids by test scores, but it's better than covering up
what's inside their heads and leaving them to be judged,
ignorantly, by what's on the surface.

5. Intermarriage is closing the gap. To the extent that IQ
differences are genetic, the surest way to eliminate them is to
reunite the human genome. This is already happening, including in
my own family. In 1970, 1 percent of U.S. marriages were between
blacks and nonblacks. By 1990, it was [38]4.5 percent. It may be
the best punch line of the IQ debate: The more genetic the racial
gap is, the faster we can obliterate it.

6. Environment matters. Genetic and environmental theories aren't
mutually exclusive. Hereditarians admit that by their own reading
of the data, nongenetic factors account for [39]20 percent to 50
percent of IQ variation. They think malnutrition, disease, and
educational deprivation account for a big portion of the 30-point
IQ gap between whites and black Africans. They think alleviation of
these factors in the United States has helped us halve the deficit.
Transracial adoption studies validate this. Korean adoption studies
suggest a malnutrition effect of perhaps 10 IQ points. And everyone
agrees that the black-white IQ gap [40]closed significantly during
the 20^th century, which can't have been due to genes.

7. IQ is like wealth. Many people who used to condemn differences
in wealth have learned to accept them. Instead of demanding parity,
they focus on elevating everyone to an acceptable standard of
living. Why not treat IQ the same way? This seems particularly
reasonable if we accept IQ in the role for which science has
certified it: [41]not as a measure of human worth, but as a
predictor of modern social and economic success.

As it turns out, raising the lowest IQs is a lot easier than
equalizing higher IQs, because you can do it through nutrition,
medicine, and basic schooling. As these factors improve, IQs have
risen. If racial differences persist, is that really so awful?
Conversely, if we can raise the lowest IQs, isn't that enough to
justify the effort? One of the strangest passages in IQ scholarship
is a recent attempt by hereditarians to minimize [42]their own
mediated-learning study because, while it "did raise the IQ of the
African students from 83 to 97, this is still low for students at a
leading university." You've got to be kidding. Screw the other
universities. Going from 83 to 97 is a screaming success.

8. Life is more than g. Every time black scores improve on a test,
hereditarians complain that the improvement is on
"[43]subject-specific knowledge," not on g (general intelligence).
But the more you read about progress in things other than g, the
more you wonder: Does g expose the limits of the progress? Or does
the progress expose the limits of g?

If the progress were on g, the test-takers' lives would be easier,
since g helps you apply what you've learned to new contexts. But
that doesn't make other kinds of progress meaningless. People with
low IQs can learn subject by subject. And they may have
compensating advantages. One of my favorite disputes in the IQ
literature is about test scores in Africa. Environmentalists argued
that African kids lacked motivation. Hereditarians replied that
according to their own observations, African kids [44]stayed longer
to check their answers than white kids did. Diligence, too, is a
transferable asset.

9. Children are more than an investment. All the evidence on race
and IQ says black kids do better at younger ages, particularly with
help from intervention programs. Later, the benefits fade.
Hereditarians say this is genetics taking over, as happens with IQ
generally. Suppose that's true. We don't abandon kids who are
statistically likely to get fatal genetic diseases in their teens
or 20s. Why write off kids whose IQ gains may not last? The
economics may not pay off, but what about human rights?

10. Genes can be changed. Hereditarians point to phenylketunuria as
an example of a genetic but treatable cognitive defect. Change the
baby's diet, and you protect its brain. They also tout
breast-feeding as an environmental intervention. White women are
three times more likely than black women to breast-feed their
babies, they observe, so if more black women did it, IQs might go
up. But now it turns out that breast-feeding, too, is a genetically
regulated factor. As my colleague Emily Bazelon [45]explains, a new
study shows that while most babies gain an average of seven IQ
points from breast-feeding, some babies gain nothing from it and
end up at a four-point disadvantage because they [46]lack a crucial
gene.

The study's authors [47]claim it "shows that genes may work^ via
the environment to shape the IQ, helping to close the nature^
versus nurture debate." That's true if you have the gene. But if
you don't, nurture can't help you. And guess what? According to the
[48]International Hapmap Project, 2.2 percent of the project's
Chinese-Japanese population samples, 5 percent of its
European-American samples, and 10 percent of its Nigerian samples
lack the gene. The Africans are twice as likely as the Americans,
and four times as likely as the Asians, to start life with a
four-point IQ deficit out of sheer genetic misfortune.

Don't tell me those Nigerian babies aren't cognitively
disadvantaged. Don't tell me it isn't genetic. Don't tell me it's
God's will. And in the age of genetic modification, don't tell me
we can't do anything about it.

No, we are not created equal. But we are endowed by our Creator
with the ideal of equality, and the intelligence to finish the job.
William Saletan is Slate's national correspondent and author of
[49]Bearing Right: How Conservatives Won the Abortion War.

Article URL: [50]http://www.slate.com/id/2178122/

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   47. http://www.pnas.org/cgi/content/abstract/0704292104v1
   48. http://www.hapmap.org/
   49. http://www.bearingright.com/
   50. http://www.slate.com/id/2178122/