First snow in
Minnesota
(c. 1895), Robert Koehler. Biracial children have IQ scores halfway between
those of white children and black children, even when they are conceived by
white single mothers and adopted into middle-class white families in their
first year of life.
You
may have heard about the Minnesota Transracial Adoption Study. It was a
longitudinal study of black, biracial, and white children adopted into white
middle-class Minnesotan families, as well as the biological children of the
same families (Levin, 1994; Lynn, 1994; Scarr and Weinberg, 1976; Weinberg,
Scarr, and Waldman, 1992). IQ was measured when the adopted children were on
average 7 years old and the biological children on average 10 years old. They
were tested again ten years later. Between the two tests, all four groups
declined in mean IQ. On both tests, however, the differences among the four
groups remained unchanged, particularly the 15-point gap between black and
white adoptees.
The
biracial children remained halfway between the black and white adoptees. Could
this be due to the parental environment being likewise half and half? Well, no.
All of them were raised by white parents, and they were adopted at an early
age: 19 months on average for the white adoptees, 9 months for the biracial
adoptees, and 32 months for the black adoptees. The last figure is emphasized
by Scarr and Weinberg (1976) as a reason for the IQ gap between the black and
white adoptees.
Fine,
but what about the IQ gap between the biracial and white adoptees? Almost all
of the biracial children were adopted at a young age and born to white single mothers
who had completed high school. From conception to adulthood they developed in a
"white" environment. If anything, the white adoptees should have
encountered more developmental problems because they were adopted at an older
age.
Could
color prejudice be a reason? Perhaps the biracial children were unconsciously treated
worse than the white children. By the same reasoning, they may have been
treated better than the black children. We can test the second half of this
hypothesis. Twelve of the biracial children were wrongly thought by their
adoptive parents to have two black parents. Nonetheless, they scored on average
at the same level as the biracial children correctly classified by their
adoptive parents (Scarr and Weinberg 1976).
The Eyferth study
Another
study found no difference in IQ between white and biracial children. This was a
study of children fathered by American soldiers in Germany and then raised by
German mothers (Eyferth 1961). It found no significant difference in IQ between
children with white fathers and children with black fathers. Both groups had a mean
IQ of about 97.
These
findings were criticized by Rushton and Jensen (2005) on three grounds:
1.
The children were still young when tested. One third were between 5 and 10
years old and two thirds between 10 and 13. Since IQ is strongly influenced by family
environment before puberty, a much larger sample would be needed to find a
significant difference between the two groups.
2.
Between 20 and 25% of the “black” fathers were actually North African.
3.
At the time of the study, the US Army screened out low IQ applicants with its
preinduction Army General Classification Test. The rejection rate was about 30%
for African Americans and 3% for European Americans. African American soldiers
are thus a biased sample of the African American population.
Another
factor is that the capacity for intelligence seems to be more malleable in
children than in adults. We see this with the Minnesota Transracial Adoption
Study. In the enriched learning environment of middle-class Minnesota families,
all of the children showed impressive IQ scores at 7 years of age. By 17 years
of age, however, this benefit had largely washed out:
--------------------
Age 7 Age 17
Black
children ----- 97 ----- 89
Biracial
children - 109 ----- 99
White
children --- 112 ---- 106
Does intelligence really decline with age because
of wear and tear on the brain? Perhaps we’re programmed to be most intelligent
in childhood. That’s when we have to familiarize ourselves with the
world. The capacity for intelligence may then be gradually deactivated as we get
older because it’s less necessary.
This
deactivation may follow different trajectories in different human groups. In
early Homo sapiens, it may have begun
not long after puberty. As ancestral humans made the transition to farming,
sedentary living, and increasingly complex societies, this learning capacity became
more necessary in adulthood, with the result that natural selection favored
those individuals who retained it at older ages. This gene-culture coevolution
would have gone farther in some populations than in others.
The Fuerst et al
study
A
recent study led by John Fuerst has confirmed the intermediate IQ of biracial
individuals, this time in adults. The research team used the General Social
Survey, which includes not only ethnic, sociological, and demographic data but
also a measure of intelligence (WordSum):
The relationship between biracial status, color, and crystallized intelligence was examined in a nationally representative sample of adult Black and White Americans. First, it was found that self-identifying biracial individuals, who were found to be intermediate in color and in self-reported ancestry, had intermediate levels of crystallized intelligence relative to self-identifying White (mostly European ancestry) and Black (mostly sub-Saharan African ancestry) Americans. The results were transformed to an IQ scale: White (M = 100.00, N = 7569), primarily White-biracial (M = 96.07, N = 43, primarily Black-biracial (M = 94.14 N = 50), and Black (M = 89.81, N = 1381).
The
same study also found a significant negative correlation among African
Americans between facial color and WordSum scores. The correlation was low (r =
-0.102), but it would be difficult to get a higher correlation because of the
measures used. Self-reported skin color correlates imperfectly with actual skin
color, which in turn correlates imperfectly with European admixture. Wordsum
likewise correlates imperfectly with IQ (r = 0.71). On a final note, the
correlation between facial color and WordSum scores was not explained by region
of residence, interviewer’s race, parental socioeconomic status, or individual
educational attainment.
References
Eyferth,
K. (1961). Leistungen verscheidener Gruppen von Besatzungskindern in
Hamburg-Wechsler Intelligenztest für Kinder (HAWIK). Archiv für die gesamte Psychologie 113: 222-241.
Fuerst,
J.G.R., R. Lynn, and E.O.W. Kirkegaard. (2019). The Effect of Biracial Status
and Color on Crystallized Intelligence in the U.S.-Born African-European
American Population. Psych 1(1):
44-54. https://dx.doi.org/10.3390/Psychology1010004
Levin,
M. (1994). Comment on the Minnesota transracial adoption study. Intelligence 19: 13-20.
Lynn, R. (1994). Some
reinterpretations of the Minnesota Transracial Adoption Study. Intelligence 19: 21-27.
Rushton,
P. and A.R. Jensen. (2005). Thirty years of research on race differences in
cognitive ability. Psychology, Public
Policy, and Law 11: 235-294.
Scarr,
S., and Weinberg, R.A. (1976). IQ test performance of Black children adopted by
White families. American Psychologist 31:
726-739.
Weinberg,
R.A., Scarr, S., and Waldman, I.D. (1992). The Minnesota Transracial Adoption
Study: A follow-up of IQ test performance at adolescence. Intelligence 16: 117-135.
13 comments:
It's interesting that vast majority of inventions/discoveries were done by those from Cro-Magnon lineage(Europeans/Euro-Americans}.So Cro-Magnons were gifted with a mutation(s) that could be considered as intelligence genes.
No evidence of an advantage for children with a white mother and black father over the other way about then?
''It's interesting that vast majority of inventions/discoveries were done by those from Cro-Magnon lineage(Europeans/Euro-Americans}.So Cro-Magnons were gifted with a mutation(s) that could be considered as intelligence genes''
A tiny minority, majority of whitey is not quite bright...
Interestingly, IQ results are very different for black and half-black Brits and black Bermudians (Robert Lindsay talks about this on greater detail). Studies also show that when Canadians (all races) are tested at American norms rather than Canadian ones, they perform much higher and score higher than American youth. It is perhaps time to consider that there is something unique about American living and culture that depresses IQs below the norms in other first-world economies.
Anonymiss,
I've seen studies that show rising IQ in "black" British students. A major reason is that a growing proportion of "blacks" in Britain are biracial children who prefer to self-identify as "black." Similarly, a growing proportion of "biracials" are children who are only 1/4 of African descent.
I've also seen British studies that show high IQ and high academic performance among Igbo children. I'm not surprised.
Perhaps it's also time to question the assumption that the term "white" covers a fixed, unvarying reality. A genetic marker for empathy has a higher incidence in “Canadian Caucasians” (50%) than in "American Caucasians” (31-37%). This may reflect differences in participant recruitment or in ethnic mix between the two countries.
http://evoandproud.blogspot.com/2015/08/a-genetic-marker-for-empathy.html
Pardon me for putting an unrelated question in this comments section. I haven't seen a general contact for you, so this seemed as good as anything.
Recently I have been trying to determine the validity of the idea that increasing mutational load is a factor (or the primary factor) in lowing Western IQ and raising rates of psychological illness, among other dysgenic affects. I suspect you are familiar with the thesis, but allow me to repeat it so we are on the same footing. Previous to the industrial revolution child mortality was at greater than 40%. This mortality was a strong filter for pernicious mutations. Post industrial revolution this filter has been lost and mutations are accumulating generation to generation. Proponents of the theory are Bruce G. Charlton, Edward Dutton and Michael A. Woodley. See this post by Charlton for more complete summary than I have provided: https://charltonteaching.blogspot.com/2014/06/dysgenics-is-mostly-due-to-reduced.html
My essential concern, other than a simple pursuit of whatever might be true, is that the mutational load theory is monumentally more pessimistic in terms of what it views as necessary to maintain a high functioning population, or even to avoid progressively dysgenic effects. I would be very interested if you have any thoughts on this subject or might suggest any sources you view as definitive. Thank you for your time.
To migrate (legally or otherwise) from a Third World country to Britain is costly; the people who make that journey are relatively rich not poor in their own countries. As a Third World country gets wealthier, more of their population can afford to immigrate, and as Diaspora communities in the West increase there will be relatives already in the Western destination to assist the newly arriving immigrants, thus requiring less and less of an investment to migrate. In the aforementioned way, immigration into the West has an inherent tendency to progressively poorer and lower IQ immigrants. There is also negative assimilation, whereby the second generation of immigrants do worse than their IQ would predict, due to being brought up in a more progressive cultural environment than they are genetically co-evolved with.
Why did your most recent article on Unz Review disappear?
Christopher,
Yes, I addressed that issue in one of my posts:
http://evoandproud.blogspot.com/2018/06/yes-decline-is-genetic.html
The Kong et al. (2017) study strongly suggests that the genetic capacity for intelligence is declining in the Western world independently of ethnic change. One explanation is that deleterious mutations are no longer being weeded out. Another is differences in fertility between social classes, or simply between fast-life-history and slow-life-history individuals, although Iceland is not as class-stratified as other Western countries.
Kong, A., M.L. Frigge, G. Thorleifsson, H. Stefansson, A.I. Young, F. Zink, G.A. Jonsdottir, A. Okbay, P. Sulem, G. Masson, D.F. Gudbjartsson, A. Helgason, G. Bjornsdottir, U. Thorsteinsdottir, and K. Stefansson. (2017). Selection against variants in the genome associated with educational attainment. Proceedings of the National Academy of Sciences 114(5): E727-E732.
Sean,
I understand your argument, but I'm not sure that immigrants were necessarily better in the past because of the relatatively higher cost of transport. A stronger factor was probably the lack of social welfare programs. I read somewhere that a quarter of Italian immigrants to the U.S. had to go home because they couldn't make a go of things in their new country.
Don,
To the best of my knowledge, my last article at The Unz Review appeared on April 4, 2016 "Farewell to Henry". He asked me to come back a few months ago, but the issue of comment moderation seems to be insurmountable. Another issue is Greg Cochran, i.e., my discomfort with Unz's vendetta against him.
What's pernicious about your opinions Frost is your insistence that IQ has much validity, if any, as an indicator of the qualities needed to survive under our current milieu, which are ever-changing. I have yet to see any adequate evidence supporting your (biased) speculation
You seem to rely on genetic essentialist, androcentric and eurocentric biases that are increasingly being challenged nowadays, esp. by marginalized groups who are gaining power.
You mention that lack of welfare programs are a factor in the retention of immigrants but these poor, uneducated people's labor was needed at the time as well. These generational poor (whose poverty is no fault of their own, see: the disparity in college admissions and opportunities between the classes) who have occupied some of the lower divisions of labor are now losing their jobs to automation and outsourcing to hyper-exploited foreign workers. We're not living in a meritocracy, Frost. We're under the tyranny of the likes of you: egocentric, psychopathic males who would rather society crumble than abandon their notion of a natural supremacy.
Look at the people who follow your blog, why are so many of your fanboys white supremashits
Frost? Do you find this incidental?
Unz was a generous patron and continues to be a gracous host to GC comments despite his recent mocking references to Ron at West Hunter. He banned me from West Hunter, which is fair enough because it is his site and his rules. I get the impression though, that GC is more my way or the highway than RU.
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