This is not necessarily "news" as it's also called 'common sense'.
But this Chinese twin study illustrates a few interesting side-points:
(1) It corroborates Western studies which show IQs are highly heritable; in fact by mid adolescence innate factors (genes, biology, etc) trump environmental ones by a huge margin. Scientists often say gene-environment contribution is 50-50, or 60-40. Turns out that may be an underestimate. And we humans are certainly not "tabula rasa" or blank slates where environment is 100%. "Good intentions" are not quite enough, and there are obvious limits to malleability, contra ostensible Western egalitarian dogma.
(2) Notice how heritability increases with age? This also contradicts the environmental hypothesis. As people get older they are exposed to progressively different and diverse environments, and consequently there *should* be progressively more social 'noise' to drown out residual differences left over from heredity, i.e. heritability should diminish rather than increase with time. Yet clearly that's not the case.
(3) If genes + environment = outcome, and when you equalize environment, differences in outcome will become proportionately larger due to genes. It's a simple equation. And it's well known that heritability of IQs are actually lower in lower socioeconomic status. (Black-white IQ differences in the US actually increase with higher socioeconomic status, a fact which totally baffles starry-eyed utopians and conventional social/environmental explanations: how can improving the problem make things worse?? http://tinyurl.com/ykagfcq )
In this Chinese study, it's actually held in a rather poor SouthWest province - Sichuan - and one should expect heritabilities to be lower. That is, one wonders if the cited heritability for global IQ aged 10-16, 0.82, may well be an underestimate.
* * * * * http://tinyurl.com/ykdfyxz Zhonghua Yi Xue Yi Chuan Xue Za Zhi. 2009 Jun;26(3):326-30. [A twin study on intelligence and processing speed heritability of children and adolescent]
[Article in Chinese]
Zhang XW, Huang Y, Xiang Y, Gao X, Situ MJ, Fang H, Zhang Y, Fu YX, Jia L, Meng HQ, Ma XH, Wang YC, Liu XH, Li T.
Mental Health Center, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041 PR China.
OBJECTIVE: To explore the effects of the genetic and environmental factors on intelligence of children and adolescent from the Southwest China Prospective Twin Registry (SCPT). METHODS: The intelligence was investigated by using the Wechsler Intelligence Scale for Children (C-WISC) in 333 twin pairs aged 6-16 years. The effects of genetic and environmental factors on IQ were analyzed by using structural equation modeling (SEM) and correlation analysis method. The effects in different sex and age groups in this population were also investigated. RESULTS: Genetic influence accounted for 0.43 of total IQ variance and 0.37 of verbal IQ in 6-16 years old children and adolescent, but there was no significant genetic effect on performance IQ. The heritability of children aged 10-16 years was higher than that of those aged 6-10 years (total IQ: 0.82 vs 0.00, verbal IQ: 0.80 vs 0.00, performance IQ:0.51 vs 0.00). In males the heritability of verbal IQ (0.47) was higher than that in females (0.05). The shared environmental influences accounted fo r the majority of variance of performance IQ in both males and females. CONCLUSION: There is moderate heritability on the total IQ and verbal IQ, while shared environmental factors played important roles on the variance of performance IQ. The heritability of IQ, verbal IQ and performance IQ are higher in older children and adolescent than that in younger children.
> This is not necessarily "news" as it's also called 'common sense'.
> But this Chinese twin study illustrates a few interesting side-points:
> (1) It corroborates Western studies which show IQs are highly heritable; > in fact by mid adolescence innate factors (genes, biology, etc) trump > environmental ones by a huge margin. Scientists often say > gene-environment contribution is 50-50, or 60-40. Turns out that may be > an underestimate. And we humans are certainly not "tabula rasa" or blank > slates where environment is 100%. "Good intentions" are not quite > enough, and there are obvious limits to malleability, contra ostensible > Western egalitarian dogma.
> (2) Notice how heritability increases with age? This also contradicts > the environmental hypothesis. As people get older they are exposed to > progressively different and diverse environments, and consequently there > *should* be progressively more social 'noise' to drown out residual > differences left over from heredity, i.e. heritability should diminish > rather than increase with time. Yet clearly that's not the case.
> (3) If genes + environment = outcome, and when you equalize environment, > differences in outcome will become proportionately larger due to > genes. It's a simple equation. And it's well known that heritability of > IQs are actually lower in lower socioeconomic status. (Black-white IQ > differences in the US actually increase with higher socioeconomic > status, a fact which totally baffles starry-eyed utopians and > conventional social/environmental explanations: how can improving the > problem make things worse?? http://tinyurl.com/ykagfcq)
> In this Chinese study, it's actually held in a rather poor SouthWest > province - Sichuan - and one should expect heritabilities to be lower. > That is, one wonders if the cited heritability for global IQ aged 10-16, > 0.82, may well be an underestimate.
> * * * * *http://tinyurl.com/ykdfyxz > Zhonghua Yi Xue Yi Chuan Xue Za Zhi. 2009 Jun;26(3):326-30. > [A twin study on intelligence and processing speed heritability of > children and adolescent]
> [Article in Chinese]
> Zhang XW, Huang Y, Xiang Y, Gao X, Situ MJ, Fang H, Zhang Y, Fu YX, Jia > L, Meng HQ, Ma XH, Wang YC, Liu XH, Li T.
> Mental Health Center, West China Hospital, Sichuan University, Chengdu, > Sichuan, 610041 PR China.
> OBJECTIVE: To explore the effects of the genetic and environmental > factors on intelligence of children and adolescent from the Southwest > China Prospective Twin Registry (SCPT). METHODS: The intelligence was > investigated by using the Wechsler Intelligence Scale for Children > (C-WISC) in 333 twin pairs aged 6-16 years. The effects of genetic and > environmental factors on IQ were analyzed by using structural equation > modeling (SEM) and correlation analysis method. The effects in different > sex and age groups in this population were also investigated. RESULTS: > Genetic influence accounted for 0.43 of total IQ variance and 0.37 of > verbal IQ in 6-16 years old children and adolescent, but there was no > significant genetic effect on performance IQ. The heritability of > children aged 10-16 years was higher than that of those aged 6-10 years > (total IQ: 0.82 vs 0.00, verbal IQ: 0.80 vs 0.00, performance IQ:0.51 vs > 0.00). In males the heritability of verbal IQ (0.47) was higher than > that in females (0.05). The shared environmental influences accounted fo > r the majority of variance of performance IQ in both males and females. > CONCLUSION: There is moderate heritability on the total IQ and verbal > IQ, while shared environmental factors played important roles on the > variance of performance IQ. The heritability of IQ, verbal IQ and > performance IQ are higher in older children and adolescent than that in > younger children.
"In males the heritability of verbal IQ (0.47) was higher than that in females (0.05)." The gender difference in heritability is unexpected. This raises question on the validity of the experiment.
ltlee1 wrote: > On Nov 2, 9:00 pm, RichAsianKid <RichAsian...@hotmail.com> wrote: >> This is not necessarily "news" as it's also called 'common sense'.
>> But this Chinese twin study illustrates a few interesting side-points:
>> (1) It corroborates Western studies which show IQs are highly heritable; >> in fact by mid adolescence innate factors (genes, biology, etc) trump >> environmental ones by a huge margin. Scientists often say >> gene-environment contribution is 50-50, or 60-40. Turns out that may be >> an underestimate. And we humans are certainly not "tabula rasa" or blank >> slates where environment is 100%. "Good intentions" are not quite >> enough, and there are obvious limits to malleability, contra ostensible >> Western egalitarian dogma.
>> (2) Notice how heritability increases with age? This also contradicts >> the environmental hypothesis. As people get older they are exposed to >> progressively different and diverse environments, and consequently there >> *should* be progressively more social 'noise' to drown out residual >> differences left over from heredity, i.e. heritability should diminish >> rather than increase with time. Yet clearly that's not the case.
>> (3) If genes + environment = outcome, and when you equalize environment, >> differences in outcome will become proportionately larger due to >> genes. It's a simple equation. And it's well known that heritability of >> IQs are actually lower in lower socioeconomic status. (Black-white IQ >> differences in the US actually increase with higher socioeconomic >> status, a fact which totally baffles starry-eyed utopians and >> conventional social/environmental explanations: how can improving the >> problem make things worse?? http://tinyurl.com/ykagfcq)
>> In this Chinese study, it's actually held in a rather poor SouthWest >> province - Sichuan - and one should expect heritabilities to be lower. >> That is, one wonders if the cited heritability for global IQ aged 10-16, >> 0.82, may well be an underestimate.
>> * * * * *http://tinyurl.com/ykdfyxz >> Zhonghua Yi Xue Yi Chuan Xue Za Zhi. 2009 Jun;26(3):326-30. >> [A twin study on intelligence and processing speed heritability of >> children and adolescent]
>> [Article in Chinese]
>> Zhang XW, Huang Y, Xiang Y, Gao X, Situ MJ, Fang H, Zhang Y, Fu YX, Jia >> L, Meng HQ, Ma XH, Wang YC, Liu XH, Li T.
>> Mental Health Center, West China Hospital, Sichuan University, Chengdu, >> Sichuan, 610041 PR China.
>> OBJECTIVE: To explore the effects of the genetic and environmental >> factors on intelligence of children and adolescent from the Southwest >> China Prospective Twin Registry (SCPT). METHODS: The intelligence was >> investigated by using the Wechsler Intelligence Scale for Children >> (C-WISC) in 333 twin pairs aged 6-16 years. The effects of genetic and >> environmental factors on IQ were analyzed by using structural equation >> modeling (SEM) and correlation analysis method. The effects in different >> sex and age groups in this population were also investigated. RESULTS: >> Genetic influence accounted for 0.43 of total IQ variance and 0.37 of >> verbal IQ in 6-16 years old children and adolescent, but there was no >> significant genetic effect on performance IQ. The heritability of >> children aged 10-16 years was higher than that of those aged 6-10 years >> (total IQ: 0.82 vs 0.00, verbal IQ: 0.80 vs 0.00, performance IQ:0.51 vs >> 0.00). In males the heritability of verbal IQ (0.47) was higher than >> that in females (0.05). The shared environmental influences accounted fo >> r the majority of variance of performance IQ in both males and females. >> CONCLUSION: There is moderate heritability on the total IQ and verbal >> IQ, while shared environmental factors played important roles on the >> variance of performance IQ. The heritability of IQ, verbal IQ and >> performance IQ are higher in older children and adolescent than that in >> younger children.
> "In males the heritability of verbal IQ (0.47) was higher than that in > females > (0.05)." The gender difference in heritability is unexpected. This > raises question > on the validity of the experiment.
If data were any guide, why should we take blanket equality a priori including male-female differences and inheritabilities?
We know men and women are not equally intelligent and they differ in their structural intelligence too for example. I agree however it's an anomaly worth pursuing.
This Chinese study on heritability is still concordant from Wikipedia: estimates in the academic research into the heritability of IQ have varied from relatively high, such as over 0.9 in a 1994 report,[6] to relatively low, such as below 0.5 in a 1997 report.[3] A general range of 0.4 to 0.8 was given by the "Mainstream Science on Intelligence", a 1994 declaration of 52 scientists in the field.[7] A 1996 statement by the American Psychological Association gave about .45 for children and about .75 during and after adolescence.[8] A 2004 meta-analysis of reports in Current Directions in Psychological Science gave an overall estimate of around three quarters.[9] The New York Times Magazine has also listed about three quarters as a figure held by the majority of studies.[10] A 1994 review in Behavior Genetics based on identical/fraternal twin studies found that it is as high as 0.92 in general cognitive ability but it also varies based on the trait, with .60 for verbal tests, .50 for spatial and speed-of-processing tests, and only .40 for memory tests.
I take from this study, whatever its flaws, nature is not only not zero but eventually become predominant.
On Nov 2, 9:00 pm, RichAsianKid <RichAsian...@hotmail.com> wrote:
> This is not necessarily "news" as it's also called 'common sense'.
> But this Chinese twin study illustrates a few interesting side-points:
> (1) It corroborates Western studies which show IQs are highly heritable; > in fact by mid adolescence innate factors (genes, biology, etc) trump > environmental ones by a huge margin. Scientists often say > gene-environment contribution is 50-50, or 60-40. Turns out that may be > an underestimate. And we humans are certainly not "tabula rasa" or blank > slates where environment is 100%. "Good intentions" are not quite > enough, and there are obvious limits to malleability, contra ostensible > Western egalitarian dogma.
if genes are more important than environment, then twin who have been separated and put in different environments - one poor the other wealthy, one rural the other urban, one is adopted the other remains in the orphanage should have the same IQ as an adult. If IQ is all that important then persons of the same IQ should be making similarly signficant contributions to society. Most of the literature I have read said this is not so. While IQ test can be a good predictor at math, verbal, and reasoning skills -- these skills by themselves are not sufficient for socio-economic success in society. The brain tends to rewire/adapt itself to the environment - so while genetics may provide the potential brain capabilities- it is the environment which triggers the brain development to its actual state.
A student's educational experience is also not merely based on schools that he/she attends but on the community that student grows up in. Parents may sire a child, but it takes a village/community to make that child into an successful and capable adult.
Part of the socio-economic success is based on access to education but other components like access to capital, access to markets, social opportunities, social skills, proper health care, and so forth can be equally as important as formal education.
> (2) Notice how heritability increases with age? This also contradicts > the environmental hypothesis. As people get older they are exposed to > progressively different and diverse environments, and consequently there > *should* be progressively more social 'noise' to drown out residual > differences left over from heredity, i.e. heritability should diminish > rather than increase with time. Yet clearly that's not the case.
Educational environments are not normally signficantly progressively different or diverse either socially or academically - especially in the USA. Poor and wealthy students tend to show similar improvements over the course of the school year. However, during the long summer vacations in the USA, the test score of poor students tend to drop while wealthy student test score rise or are stable. School systems in other countries which have shorter school vacation and thus longer school years have higher average test score in verbal and math scores regardless of family background.
> (3) If genes + environment = outcome, and when you equalize environment, > differences in outcome will become proportionately larger due to > genes. It's a simple equation. And it's well known that heritability of > IQs are actually lower in lower socioeconomic status. (Black-white IQ > differences in the US actually increase with higher socioeconomic > status, a fact which totally baffles starry-eyed utopians and > conventional social/environmental explanations: how can improving the > problem make things worse?? http://tinyurl.com/ykagfcq)
In the USA genetics and environments are not equalized in the real world IQ testing and educational situations.
There are inexpensive and lo tech ways to address this ----------------------------------------------------------------- However, it has been found that IQ/ math/verbal/reasoning test score for lower socioeconomic students can be increased by providing summer school ( or extending the school year, or restricting school holiday vacations in poorer districts to less than two or three weeks) In larger families, a younger child's IQ is raised when older children assist younger child's educational and social development. Also in extended family situations, extended family mentoring/support can substitute for the lack of parental time and boost a student's educational level over time.
Neo wrote: > On Nov 2, 9:00 pm, RichAsianKid <RichAsian...@hotmail.com> wrote: >> This is not necessarily "news" as it's also called 'common sense'.
>> But this Chinese twin study illustrates a few interesting side-points:
>> (1) It corroborates Western studies which show IQs are highly heritable; >> in fact by mid adolescence innate factors (genes, biology, etc) trump >> environmental ones by a huge margin. Scientists often say >> gene-environment contribution is 50-50, or 60-40. Turns out that may be >> an underestimate. And we humans are certainly not "tabula rasa" or blank >> slates where environment is 100%. "Good intentions" are not quite >> enough, and there are obvious limits to malleability, contra ostensible >> Western egalitarian dogma.
> if genes are more important than environment, then twin > who have been separated and put in different environments > - one poor the other wealthy, one rural the other urban, > one is adopted the other remains in the orphanage > should have the same IQ as an adult. If IQ is all that > important then persons of the same IQ should be making > similarly signficant contributions to society. Most of > the literature I have read said this is not so. While IQ > test can be a good predictor at math, verbal, and reasoning > skills -- these skills by themselves are not sufficient > for socio-economic success in society. The brain > tends to rewire/adapt itself to the environment - so > while genetics may provide the potential brain > capabilities- it is the environment which triggers > the brain development to its actual state.
(a) Heritability from the predominance of studies is >0.50 as quoted on this thread, and in some cases >0.80; it certainly is not zero. (b) Even if Einstein can be starved to death, it does not follow that everyone will be Einstein because of adequate nutrition; in fact modern societies esp in the US is not 'environmentally deprived' or 'nutritionally deprived' even for the lower classes - witness the rates of obesity (b2) If it's parenting styles that's at fault maybe it's the parents who are low IQ to begin with who lack that "time-horizon" and who don't care for their children (b3) Why should anyone expect a thousand say grade 5 kids averaging an IQ of 80 to do better academically in university, in the aggregate, compared to a thousand grade 5 kids averaging an IQ of 120 anyway? (c) The non-zero factor of heredity thwarts "You can be *whatever* you want to be" which is merely the modern equivalent of Plato's Noble Lie.
> A student's educational experience is also not merely > based on schools that he/she attends but on the > community that student grows up in. Parents may > sire a child, but it takes a village/community to > make that child into an successful and capable adult.
And that's where race and their differential abilities comes in. In the US, the ratio of above IQ (>110) compared to low IQ (<90) is as follows for Asian vs black communities:
Asian: 3:1 Black: 1:12
That is, there are no fewer than 36 times of above IQ Asians compared to blacks, per capita low IQ.
That's why some communities are anchored while others fly.
And if what you said is true on the importance of environment (and think how that further magnifies on a country scale) you'll appreciate the importance of group/aggregate/average IQ even more. That's why even small differences matter a great deal - more than on an individual level.
> Part of the socio-economic success is based on > access to education but other components like > access to capital, access to markets, social opportunities, > social skills, proper health care, and so forth > can be equally as important as formal education.
"Part", yes. See above on how the ensuing non-parity of the collective environment feedbacks on outcome.
>> (2) Notice how heritability increases with age? This also contradicts >> the environmental hypothesis. As people get older they are exposed to >> progressively different and diverse environments, and consequently there >> *should* be progressively more social 'noise' to drown out residual >> differences left over from heredity, i.e. heritability should diminish >> rather than increase with time. Yet clearly that's not the case.
> Educational environments are not normally signficantly progressively > different or diverse either socially or academically - especially in > the USA. > Poor and wealthy students tend to show similar improvements over the > course of the school year. However, during the long summer vacations > in the USA, the test score of poor students tend to drop while wealthy > student test score rise or are stable. School systems in other > countries > which have shorter school vacation and thus longer school years > have higher average test score in verbal and math scores regardless > of family background.
Most students (excluded retarded and gifted ones) need to study 3Rs and essentially undergo the same elementary school curriculum; yet not all high school students choose to study physics or chemistry. In universities, people choose arts vs sciences and professional school for various reasons, but certainly compared to elementary schools students have increasing choice with a wider menu of options. And similarly as a grade 2 kid you may only be permitted to play with your neighbor's kid; when you're in your 50s you may maintain multiple transnational relationships through travel or internet etc etc. No matter how much a Down's child or a IQ 70 child tries, he/she is, probabilistically speaking, very unlikely to ace medical or law school or become a first rate theoretical physics professor.
>> (3) If genes + environment = outcome, and when you equalize environment, >> differences in outcome will become proportionately larger due to >> genes. It's a simple equation. And it's well known that heritability of >> IQs are actually lower in lower socioeconomic status. (Black-white IQ >> differences in the US actually increase with higher socioeconomic >> status, a fact which totally baffles starry-eyed utopians and >> conventional social/environmental explanations: how can improving the >> problem make things worse?? http://tinyurl.com/ykagfcq)
> In the USA genetics and environments are not equalized > in the real world IQ testing and educational situations.
> There are inexpensive and lo tech ways to address this > ----------------------------------------------------------------- > However, it has been found that IQ/ math/verbal/reasoning > test score for lower socioeconomic students can be > increased by providing summer school ( or extending > the school year, or restricting school holiday vacations > in poorer districts to less than two or three weeks) > In larger families, a younger child's IQ is raised when older > children assist younger child's educational and social > development. Also in extended family situations, extended > family mentoring/support can substitute for the > lack of parental time and boost a student's educational > level over time.
In the US, even wealthy black parents have below-average SAT scoring children compared to whites/Asians:
And when socioeconomic status is corrected for, racial differences remain, in fact they tend to be larger for the same reason as I mentioned ( http://tinyurl.com/ykagfcq ): you can starve Einstein to death (i.e. equalize everyone, just like communism, make everyone equally poor); you will not make everyone Einstein or make everyone equally rich. And when you equalize environment, the remaining differences will be increasingly due to non-environment factors.
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