November 15, 2011

Nature v. Nurture solved!

From The New Republic:
The Two Year Window
The new science of babies and brains—and how it could revolutionize the fight against poverty.
Jonathan Cohn

The End of Nature v. Nurture?
The New Science of Babies and Brains

A decade ago, a neuroscientist named Charles Nelson traveled to Bucharest to visit Romania’s infamous orphanages. There, he saw a child whose brain had swelled to the size of a basketball because of an untreated infection and a malnourished one-year-old no bigger than a newborn. But what has stayed with him ever since was the eerie quiet of the infant wards. “It would be dead silent, all of [the babies] sitting on their backs and staring at the ceiling,” says Nelson, who is now at Harvard. “Why cry when nobody is going to pay attention to you?” 
Nelson had traveled to Romania to take part in a cutting-edge experiment. It was ten years after the fall of the Communist dictator Nicolae Ceauşescu, whose scheme for increasing the country’s population through bans on birth control and abortion had filled state-run institutions with children their parents couldn’t support. Images from the orphanages had prompted an outpouring of international aid and a rush from parents around the world to adopt the children. But ten years later, the new government remained convinced that the institutions were a good idea—and was still warehousing at least 60,000 kids, some of them born after the old regime’s fall, in facilities where many received almost no meaningful human interaction. With backing from the MacArthur Foundation, and help from a sympathetic Romanian official, Nelson and colleagues from Harvard, Tulane, and the University of Maryland prevailed upon the government to allow them to remove some of the children from the orphanages and place them with foster families. Then, the researchers would observe how they fared over time in comparison with the children still in the orphanages. They would also track a third set of children, who were with their original parents, as a control group.

Back in 2007, I reported on Dr. Nelson's study. He found that the poor kids who continued to get warehoused in these cheerless Romanian orphanages averaged IQs of 73, while those who got to move in with foster parents averaged 81. A control group of non-orphans averaged 109. 

As I said in 2007, an 8 point boost for getting out of a bleak Romanian orphanage and into a family setting seems a quite plausible nurture effect to me. But, what in the world accounts for the 28 point gap between the fostered kids and the control group of non-orphans?

I found an earlier report by Nelson noting a big ethnic difference:
"Of the 136 institutionalized children included in the study, 78 are of Romanian ethnicity (57.4%), 36 are Rroma Gypsy (26.5%), 1 is Turkish (0.7%), 1 is of subcontinent Indian extraction (0.7%), and the remaining 20 (14.7%) could not be classified. ...

The control group with the 109 average IQ is much different in ethnicity:
"Of the 72 who consented to participate, 66 children (91.7%) were Romanian, 4 children (5.6%) were Rroma, 1 child was Spanish, and 1 child was Turkish."

In summary, major selection effects seem to be driving part of the almost two-standard deviation IQ gap between the foster care and biological family groups.

Before America goes out and more or less kidnaps black babies away from poor black mothers in order to raise their IQs -- the upcoming Borrowed Generations national apology of 2056 -- some more pointed research is needed.

If there really is a critical 2-year-window where children who don't get talked at enough are doomed for life, that would imply certain falsifiable hypotheses:

- For example, some poor black mothers are taciturn and others are loquacious. Do the loquacious ones have children who grow up to have higher IQs relative to their mothers IQs? If so, how much?

- If what really matters to a person's adult IQ is having a middle-class upbringing as a small child with a mother who constantly is nudging you to look at this thing or that thing, wouldn't it be cheaper to encourage blacks to point out stuff to their kids rather than to take their kids away from them for 14 hours per day? If it's all culture, why not improve the culture of the black mothers? That doesn't strike me as impossible to do. If, say, Oprah and Beyonce teamed up to push for a decade to get mothers to talk more to their babies, I wouldn't be surprised if they could move the needle.

- Many middle class white women turn most of the baby-raising over to low IQ servants, many of whom don't speak English and don't have middle class urges to point out every damn thing under the sun to the babies they are caring for. Are these middle class white women damaging the IQs of their own children? Should they leave the workforce and raise their own kids? But if white women stop hiring Honduran illegal immigrants to raise their own babies for them, then who is going to raise the babies of poor black women for them?

48 comments:

Anonymous said...

I think it's pretty obvious that a kid that is literally NEGLECTED and has next to no human interaction is going to end up retarded.

I'm not going to go too far in praising the parenting skills of ghetto moms, but it's pretty clear that most of them aren't just locking their kids up in rooms for days with no human interaction. Even if they're just getting plopped in front of the TV and being fed Cheetos, that's miles and miles better than a Romanian orphanage.

Q said...

A control group of non-orphans averaged 109.


Hold on thar .... a control group of Romanians had an IQ of 109?

Something is amiss there. Lynn gives Romania an average IQ of 94. Rindermann gave them 89.

ziel said...

Hold on thar .... a control group of Romanians had an IQ of 109?

From the article: "Of the 72 who consented to participate"

That means they had to fill out forms...right there, a big boost to the average.

Carol said...

The Ad Council used to run spots purporting to teach parents how to talk to their children. The "parents" in them talked really stupid.

The ads ran on talk radio mostly in the early morning and late night hours. Not sure how many ghetto moms listen to Lars Larsen or Kim Kommando.

Felix said...

The so called "critical period" is a well documented phenomenon. Several pretty convincing experiments have been done on vision, for example, that show an irreversilbe loss of function in certain brain regions when those regions are deprived of stimulus during the critical period. Check this one out for starters:

http://thebrain.mcgill.ca/flash/capsules/experience_rouge05.html

If something as basic as binocular vision can be impacted by stimulus deprivation during a certain developmental period, it's even easier to believe a more complex phenomenon like learning in humans could likewise be influenced.

Assistant Village Idiot said...

Some knowledge here. Remember that the environments for orphans have varied throughout Romania through this time. There are state orphanages, private orphanages, abandoned baby rooms at local hospitals, and semi-abandoned village children. This complicates much measurement.

Q, the Romanian averages include the Roma, so that's part of it. I agree that 109 seems high. But some large difference between Roma and the majority population is quite plausible to anyone who has spent time there.

The first comment is important. The deprivation and lack of stimulation of a subgroup of Romanian orphans was profound: Bottle-fed with a propped bottle, no words; tied into cribs so they would not throw themselves onto the stone floors; diaper changed once a day. Children that are "understimulated" by American standards still have plenty they can teach themselves by exploring.

Anonymous said...

The question is already settled in an experimental American setting.

http://ideas.repec.org/p/ifs/cemmap/22-10.html

Giving disadvantaged pre-school black kids a two year intensive program did absolutely nothing for their adult I.Q.

Apparently the environment black American kids live in is fine for I.Q development, black mothers plus society do the minimum required for the brain to develop.

But norms and character are more malleable than I.Q, so the bad environment matters more.

On a semi-related topic:

http://politicalticker.blogs.cnn.com/2011/11/15/cnn-poll-obama-ranks-low-among-recent-incumbents/

Psammetichus said...

Hey, this is old news. I answered this question more than 2500 years ago! (Check out Herodotus, Book Two Chapter Two.) Turns out if you starve kids of human attention, they babble in Phrygian. Go figure.

Better than Romanian, I suppose.

Q said...

I agree that 109 seems high. But some large difference between Roma and the majority population is quite plausible to anyone who has spent time there.


That's true. But the majority population having an IQ of 109 is implausible. That's a useless control group. Using the average Romanian IQ as found by Lynn and Rinderman suggests that moving the orphan kids in with foster parents brought them within shouting distance of the Romanian norm. The remaining discrepancy can then be accounted for by the disproportionate number of gypsies.

Anonymous said...

How do mixed-race kids where dad is black and mom is white do compared to black mom/white dad kids? Isn't that a pretty simple way to suss out the degree to which black maternal culture affects childhood development?

Anonymous said...

Wasn't it Quintillian who warned upper class families not to let slaves raise their children because their speech reflected confused thinking?

Anonymous said...

Because of the Romanian strongman's policy there were many white babies available to adopt. Canadians flocked to get them. Then the Canadian government, in an act of vicious cruelty, imposed all these actions making it almost impossible to get them. Their "crime" was that they were white babies and from Europe. Canadians were given a free hand to adopt unwanted (females only) Chinese babies though.

Marlowe said...

Your pal Pinker has most of the answers to these questions, n'est pas?
I recall reading in THE LANGUAGE INSTINCT something to the effect that mothers talking to their infants doesn't & cannot account for language acquisition in its entirety.

Polynices said...

Deaf kids raised together invent their own sign languages (google it, happened in central america somewhere) so I'm pretty sure mom talking to baby isn't that important for basic language acquisition. We're just wired for it.

I'd bet that dumb parents don't talk to their kids much and of course dumb parents have dumb kids... but that doesn't mean not talking much causes the dumbness, ya know?

edgy gurl said...

I don't know why you're harping on this again. Black women talk a lot, easily as much as white women, and are fairly eloquent though their language might not be standard English.

What's probably happening is an effect where younger children are being supervised by their slightly older siblings most of the time. I'm pretty sure this has been noticed across races with the typical outcome being that the older kid/kids who get more time with mom have higher IQs.

RS said...

> major selection effects seem to be driving part of the almost two-standard deviation IQ gap

Probably you meant two-thirds or whatever.

More importantly, if this is not randomized then it doesn't merit the word 'study' - not by half. Of course if it is randomized it is a very important finding.

Anonymous said...

"For example, some poor black mothers are taciturn..."

Oh, yeah? Name one.

jody said...

reticent african moms is the problem? now i have heard it all.

Anonymous said...

That was a joke, right?

There's no reason it should be. The idea should be amelioration, not equalization. Ameliorating black outcomes is more about "don't do" than "do do," and the former is generally much simpler than the latter. And even some very simple items on the "do do" list can make a big difference. Amelioration is definitely possible. Equalization, on the other, is not only unachievable (at least there's not much good reason to think so), it isn't even a worthy or wise objective.

Silver

Melykin said...

RS said:

...if this is not randomized then it doesn't merit the word 'study'...
---------------------------

The only way to make if randomized would be to take a group of pregnant mothers and randomly assign them to two groups: one group will be forced to keep the baby and raise it, the other group will be forced to surrender the baby to the orphanage. Obviously such an experiment is not going to happen--a least I hope it is not!

Since the groups of mothers were self-selected they were almost certain to be be systematic difference between them, including genetic differences. For example the parents who surrendered their babies might have had lower IQ's on average than the mothers who didn't. They were probably also more likely to have problems with drugs or alcohol. Maybe a lot of the orphan babies had fetal alcohol syndrome.

Anonymous said...

That means they had to fill out forms...right there, a big boost to the average.

There is NOTHING in all of sociology quite like the effect of a self-selecting statistic.

N.O.T.H.I.N.G.

jody said...

"The so called "critical period" is a well documented phenomenon."

well the vision part is true at least. this is why "the matrix" could never happen. plot hole! you can't just open your eyes at age 27 and start seeing. if you don't start seeing within a few years after you are born, you will probably never be able to see.

the nurture part of the IQ development hypothesis here is somewhat within the realm of the possible, with a caveat - it can probably only go one way. you can drop a person's potential brain function by a lot, but you probably can't make it go up much past their normal potential.

so you can whack down their IQ 8 points below group average by deliberately stripping away any interaction from their life and forcing them live in a 15x15 jail cell for the first 12 years. but you can't boost their IQ 8 points above group average by taking them out of their normal environment while growing up and instead putting them into "super stimulating school!".

neuroscientists have done these same exact experiments on animals, forcing the experiment groups to live in boring cages where nothing happens, the environment is static, and there are no objects to interact with. control animals get to live in normal quarters, with tunnels between cages, other animals to socialize with, and toys to climb on and manipulate.

then you kill the animals when they are a couple years old, and open their heads, and look inside their brains. the experiment group animals have brains with less neuron connections and more simple, less developed nerve connections. while the control group animals have the typical lattice of neurons reaching out to each other neurons, making myriad connections.

A "secret" doomsday machine!?!?!! said...

Per Edward teller's memoirs dad was a Hungarian speaker while ma was only fluent in German (the local rabbi suspected the child might be retarded from showing no verbal aptitude by age 3). Perhaps this will be the craze following Mozart tapes--putting kids w/ mutually unintelligible parents.

catperson said...

Hold on thar .... a control group of Romanians had an IQ of 109?

Something is amiss there. Lynn gives Romania an average IQ of 94. Rindermann gave them 89.



They probably used an old test with outdated norms thus inflating everyone's IQ (orphans and non-orphans); a very common mistake especially before people became aware of the Flynn Effect.

Anonymous said...

1848: Manifesto of the Communist Party: Chapter 2:

"Do you charge us with wanting to stop the exploitation of children by their parents? To this crime we plead guilty."
...
"But, you say, we destroy the most hallowed of relations, when we replace home education by social."

----------------------

Anatoly Lunacharsky, Soviet People’s Commissar of Enlightenment:

"Our problem now is to do away with the household and to free women from the care of children."
...
"have well-organized quarters for children ... where they will be supervised by trained pedagogical and medical personnel."

---------
Secular Humanist Bulletin Volume 13, Number 2:

"Advocatus Diaboli
by Tom Flynn

Replacing Our Last Cottage Industry "
...
"Finally, (3) the family stands in the way of another implicit humanist goal: decoupling sex from reproduction and reproduction from parenting."
...
"We expect specialists to build our cars, raise our buildings, make our clothing, write our software - the list is endless. Perversely, only society's most precious products - us - are still entrusted to cottage industry."
...
"While procreation and parenting remain yoked, most children are doomed to be raised by amateurs."
...
"Science-fiction masters like Robert A. Heinlein, Isaac Asimov, and others portrayed futures in which the family had been eclipsed by licensed, professionalized alternatives."

----------
Romanian Orphans

rob said...

Taking children away from the black lumpenproletariat is the dumbest possible thing to do with them.

First, all the white women who won't have as many kids because they spent their reproductive years raising brood parasites. srsly, let's have stupid and irresponsible women have children, then smart women can raise them instead of their own children. What could wrong!

Second, a fair chunk of the women who care for the low-end immature blacks won't have kids because they'll think that all kids will behave like nth generation welfare rats fathered by whatever crackhead was happened to be outa jail and lookin' fine when the babymomma wanted dat ass tapped.

Finally, when the r-selected black babymommas don't even have to put in the minimal effort of parenting that they do now they'll have even more children.

God, has there been any social program since the March through the Institutions that has even had making the problem smaller as a goal?

Lara said...

My son had some speech delays and I was told by several people it was because I didn't talk to him enough. I started to be more aware of it and talk to him more and his speech improved.

Chicago said...

The abandoned kids probably had dysfunctional biological parents to begin with; alcoholics, prostitutes, drug users, mentally ill or dimwitted. People don't necessarily give up their infants just because they have little money; there are other reasons besides.

Anonymous said...

well the vision part is true at least. this is why "the matrix" could never happen. plot hole! you can't just open your eyes at age 27 and start seeing. if you don't start seeing within a few years after you are born, you will probably never be able to see.

Oliver Sacks tells the story of middle-aged blind man who became able to "see" (in a fashion) when the doctors figured out what was wrong with him. It was a lovely experience for him, at first, but of course his therapists insisted that he learn to rely on sight to the same extent that sighted people do. He couldn't; for example, he couldn't tell what things were just by looking at them - he had to touch them as well.

The result was misery and early death. F*cking therapists.

Cennbeorc

Anonymous said...

The orphans were probably not breast fed.

From Slate:

http://www.slate.com/articles/life/family/2007/11/the_breast_and_the_brightest.html

"Now there's new evidence about the gold ring of breast-feeding benefits—extra IQ points. It's a finding with a twist. The researchers report that breast-fed babies get an average IQ advantage of 6.8 points—a nice step up—but only if they carry a certain genetic variant. If you've got the gene and your mother nurses you, she is making you smarter. If you don't have the gene, the nursing is for naught, IQ-wise. What are we to make of this?"

Catperson said...

People think the brain is like a muscle, that if you exercise mentally (get stimulation in childhood) you will be smarter. But intelligence is much more like height than like muscle. Just as lifting weights or stretching can't make you taller, going to a more stimulating environment can't make you smarter.

Yes children moved out of orphanage might score higher on IQ tests, but these gains are probably a reflection, of the better test taking skills that a family environment provides, not a true increase in intelligence. Similarly, children might stand taller against a tape measure when moved out of an orphanage, but it's a reflection of a family environment giving them shoes to wear and teaching them better posture, not a genuine increase in height.

The abecedarian study took kids from poor inner-city homes and exposed them to constant intellectual stimulation for the first 5 years of life. The result was a modest 4 point increase in IQ, but even this may not have been a true increase in intelligence, because it was concentrated in the verbal half of the IQ test which reflects acquired knowledge rather than directly measuring real fluid intelligence. Animal studies may prove that stimulation increases brain connections, but these studies involve scenarios far more extreme than most humans will ever encounter, and the increase in brain connections might not be severe enough to produce a significant intelligence increase.

People who want to increase the intelligence of the disadvantaged should focus on the biological environment rather than the social/cultural/psychological environment. Probably nutrition is the biggest factor, as both height and intelligence test performance has increased by over1 SD over the 20th century.

Conatus said...

If Oprah convinced black moms to talk to their kids more it might change the current method of inner city child rearing which is a variant of the Cheerios and TV method or ‘just make sure they are still alive.’ But to what end? I knew a kid named Omar whose Mom was a junky and the fallback position, his grandparents, were alcoholic horsetrack addicts. They were never there and Omar was totally ignored, at least from the age of five on when I knew him. He was smart enough to get by and definitely was not staring dully at the world. I was glad the kid was three feet tall when I knew him. He was a scary five year old. The point is his IQ was fine but his world view was not benign, it was toxic. I remember when he proudly showed me how he had cut the whiskers off his dog with some scissors…ha ha. Omar ended up shot to death in some unsolved murder over on New York Ave.

Anonymous said...

"We expect specialists to build our cars, raise our buildings, make our clothing, write our software - the list is endless. Perversely, only society's most precious products - us - are still entrusted to cottage industry."

(a) A minor point. People don't demand "the best." They settle for what's "good enough." People don't eat fast food because McDonald's workers are "hamburger specialists." Almost anyone could make a tastier home-cooked hamburger if took the time. But McDonald's is "good enough" for what people want that they settle for it.

(b) Love is the essential "skill" required in raising children and biological parents possess more of it than anyone else. Beyond this specialists are not required because biology/heredity is the biggest factor influencing long-run development.

Silver

PS - (c) Yes, these commie social engineers are well beyond insane. Biological determinism is a stern and uncompromising doctrine and it's easy to see why so many (including me) hope to disprove it. But if there's any consolation to the "hard" version of it it's that demographic ignoramuses like family-hating commmies will in due course be bred out of existence. Yippee.

Maya said...

Silver,

Commies might be crazy, but they aren't known to be family hating everywhere. In Soviet Union, even though the state provided free (and, need be, overnight) daycare and full day preschool, staying at home to raise the kids was encouraged and counted as working years towards the retirement pension for women until the youngest child turned 16. Maternity leaves were long. Either parent had the right to take a week-long sick leave, if the child's pediatrician signed a note that the kid had the flu/chicken pox/bad cold. People with small kids were known to miss work all the time, unless the mother was officially registered as a stay at home mom. Families with more than 2 children were (and still are) offered all kind of perks like free medications and free use of public transportation. I'm sure that if more support were offered to the responsible people who want to raise their kids right, these types of people would have more kids.

Anonymous said...

Many middle class white women turn most of the baby-raising over to low IQ servants


That's a rather Whiskey-ish sentiment. And as with so many Whiskey-ish sentiments, it's not really true. Perhaps a lot of people who think of themselves as being middle-class hire nannies. Because in America most of us like to think of ourselves as being middle-class, even if we're a doctor and our spouse is a lawyer.

Anonymous said...

That's bullshit, Maya, go find an old Russian woman and ask her.

Maya said...

"That's bullshit, Maya, go find an old Russian woman and ask her."

Got plenty of relatives from all over the former Soviet Union as well as my own childhood experience. One of my favorite childhood memories is that of contracting ring worm because my dad and I got to miss a week of work and preschool and just hang out together without me feeling sick. There are a bunch of other times when mom or dad stayed home with us, but flu and chicken pox aren't as fun as the ring worm. Mom decided she was done working when I was 5 and my brother was 9. My great grandmother put her teaching career on hold until her youngest girl (my great aunt) turned 16. She received full pension. When my sister was born, a bunch of things, like the transport passes, became free. I could go on and on and on. You, sir/ma'am are misinformed.

Anonymous said...

Maya,

I have in mind the "New Left" ie cultural leftist, crowd. They're all kinds of crazy. Hating families is just a part of their hatred of life in general. I'm sure they don't quite see it that way, but just look at what they disdain: families, ugh; children, ugh; ethnic belonging, ugh; productive achievement, ugh; buildings, monuments, factories, offices, machinery -- testaments to mankind's ingenuity -- ugh. (White people, triple ugh!) They're mad.

Now, the old style economic commies were a different breed. I happen to think their economics suffered from some severe flaws but it was intended to "advance life," if I can put it that way. I'm (partly) from eastern lineage myself so I've heard all about how lovely certain things were under the commies, and even caught a brief glimpse on a trip as a kid. Flawed but hearts in the right place I would describe it.

The "New Left" are just reality-hating creeps.

Silver

Anonymous said...

Steve, this was a great post. I laughed out loud four or five times.

Anonymous said...

Beware of studies like the Romanian one:
most are (as this one obviously is) tendentious attempts to manipulate public opinion via wild extrapolations from obviously tweaked studies.

The African-American community is riddled with pathology, there are any number of things we could do to help them to raise their children in more healthy ways, and increased intelligence would probably be one of the outcomes, along with better mental health generally.

The important thing to remember is that African-American IQ is ALREADY impressively high compared to black IQ globally:

lost in the sea of moaning and groaning about performance gaps is the reality that we have ALREADY performed a miracle in the US.

Heroic efforts might squeeze a couple more IQ points out of blacks, but we have probably already raised their cognitive abilities about as far as they will go.

As for middle-class women hiring stupid nannies:
it is a rampant practice, and very destructive to child development.

It seems to me that professional European women are much more choosy about daycare, that they tend to shopp around for something almost utopian. But that is anecdotal.

Anonymous said...

I tried posting this before but it didn't make the cut for some mysterious reason. This time I'll give more detail.

I used to volunteer in an orphanage in Central America. The nums working there drugged the young children during the day so that they would not make noise and cause problems. This caused the young children to lay on their backs and stay quiet, just as is described in the article. The nuns did not see any problem with this.

I think that this is what explains the children's silence better than neglectful cargivers. Neglected children will still babble to themselves or babble to each other and giggle and wave.

rob said...

First anon is right. Going from 'deprivation in Romanian orphanage causes an X-point IQ disadvantage' to 'black moms are so dumb and neglectful that the deprivation causes a Y-point IQ disadvantage is kinda like noticing that when people are doused in gasoline and ignited the get burned, and then deciding that letting a match burn down to your fingertips will burn off your hand.

How do mixed-race kids where dad is black and mom is white do compared to black mom/white dad kids? Isn't that a pretty simple way to suss out the degree to which black maternal culture affects childhood development?

It's been done: having a black mother reduces IQ, bu Just a guess, it isn't so simple: old mulattoes usually had black mothers. Young ones usually have white mothers. Getting big samples of white-father and black-father mulattoes is either hard, because one group is pretty rare, or any results will be mediated by possible environmental effects.

There's the issue of SES: black men who marry (not sure about impregnate) white women are better than the average black. White men who marry blacks are mostly dregs. Then again, white women who get involved with blacks are dumber than average, and I don't know about black women who marry whites, I'd guess they're smarter than the average for black women. The above looks symmetrical, but size matters, and it's unlikely that the SES effects are equal in magnitudes both ways.

Yet another reason: black-father mulatoes are usually raised by the white mother w/o much 'paternal' effort: they're raised in white areas, go to white schools,etc because that's were the mom and grandmother live.

Finally there are imprinting effects: sometimes the maternal or paternal copy of gene is inactivated. Some of those are potentially related to IQ, that'd confound results even if

There's also the issue of how equal is equal inheritance: boys have relatively more genetic material from their mothers than fathers compared to girls. For boys, any alleles on the X chromosome that influence IQ will be inherited from the mother only. and that'll look like a maternal effect. If the white IQ advantage is genetic, then boys with black mothers/white fathers will be dimmer than girls from the situation. Boys with white moms and black fathers should be smarter than similar girls.

Actually, the last one only takes a few assumptions, and since the hypothesis can be tested by measuring IQ differences within families, it wouldn't take all kinds of mulattoes and more or less eliminates the they don't need all kinds of mulattoes. Not sure how valid the assumptions all are: In a smarter population IQ-boosting alleles will tend to be spread fairly widely throughout the genome, including the X chromosome. And IQ-affecting alleles are present on the X chromosome at reasonably high frequencies so that genetic variation in the X chromosome underlies a fair amount of IQ variation, either within or between populations. So far as I know, the X-linked intelligence hypothesis has never been tested, which is odd, because it should be really easy: find a bunch families where say the father is much smarter than the mother, then see if daughters in those families are much smarter than the sons on average. Anyway, that hypothesis is but that asserts that X chromosome variation is responsible for a disproportionate share of IQ variation within population. The mulatto test just requires that alleles on the X chromosome cause some of either within or between population variance, or both.

The mulatto sex difference test will not be confounded by SES differences between WM/BW and BM/BW parents and enables the two types to be compared.

Summary: If the gap is partially (or all) genetic, and the variation on the X chromosome causes a fair amount, it should be possible to tease apart how much of the racial gap can be attributed to genes that influence intelligence and how much is caused by genes that influence maternal investment in utero.

fbi flipper said...

". White men who marry blacks are mostly dregs."

I doubt this is true. If it is actually marriage you mean. Often they work for the government in do-gooder, high-paid type jobs, with a lot overseas travel. Seen it.
No--I don't think white men who marry black women are likely to be the dregs. I keep thinking of that poor couple who was murdered by the 4 blacks marines in California..
In fact, nowadays there is less fetishism surrounding the wm/bw duo. than the other way round, and they are likely to marry because they truly like each other. Whether these unions last, I dont' know.

And I say this as a white woman.

dcite said...

"Hold on thar .... a control group of Romanians had an IQ of 109?

Something is amiss there. Lynn gives Romania an average IQ of 94"


When you talk about IQ among children, it's different than for adults. Children score 109 but then it reduces when they hit puberty. This is what confused people about the apparent gains of black kids raised by whites. They scored high, but their scores dropped to the black or mixed norms when they hit puberty, no matter how they'd been raised.

Anonymous said...

You, sir/ma'am are misinformed.

Your family had some kind of special deal going. Must have been nice.

Maya said...

"Your family had some kind of special deal going. Must have been nice."

Yes, the whole world is actually a TV show with me as the main character. I'm the female Truman. That's why the experiences of the other families I've met through school, dance lesson, summer camp and parents' work matched that of mine. The producers don't want me to catch on. My family's special deals included factory barracks, Siberian work camps and watered down anesthesia during surgeries, among other things.

Anonymous said...

The important thing to remember is that African-American IQ is ALREADY impressively high compared to black IQ globally

Heroic efforts might squeeze a couple more IQ points out of blacks, but we have probably already raised their cognitive abilities about as far as they will go.


Ongoing race-mixing has raised and is continuing to raise the average "black" IQ in America.

This has been counteracted to a large extent by the "nurture" side of things - our blacks are smarter on average than they were sixty years ago, but they behave more stupidly and self-destructively due to the cultural/social changes in America. These changes have affected whites as well as blacks - white rates of out-of-wedlock births and other indicators of social pathology are at rates which were found alarming among blacks back in 1965 when The Negro Family: The Case For National Action was published.

corvinus said...

There's the issue of SES: black men who marry (not sure about impregnate) white women are better than the average black. White men who marry blacks are mostly dregs. Then again, white women who get involved with blacks are dumber than average, and I don't know about black women who marry whites, I'd guess they're smarter than the average for black women. The above looks symmetrical, but size matters, and it's unlikely that the SES effects are equal in magnitudes both ways.

I'm sure you're more or less correct. "He-fool marry she-fool", as the old saying goes. In other words, there is assortative mating by IQ. This, of course, has the effect of keeping the races segregated by IQ, since the small number of high-IQ blacks are highly likely to become mulattoes and "high yellers" in the next generation (especially if male) or not pass their genes on at all (especially if female; think Condi Rice).

In fact, nowadays there is less fetishism surrounding the wm/bw duo. than the other way round, and they are likely to marry because they truly like each other. Whether these unions last, I dont' know.

On an AmRen article posted about a week ago, there was something to the effect that WM-BF couples are actually only about HALF as likely to divorce as the average, whereas WF-BM couples were about TWICE as likely to divorce. The WM-BF stability surprised me, given how blacks have a reputation for being transients with relationships.

And counter to what Whiskey might say, in fact white women seemed to be more likely to divorce ANY race of nonwhite partner than a white one.