# Race differences in average IQ are largely genetic **URL:** \ **Category:** Great Debates\ **Created:** [May 27, 2012, 12:28pm UTC](https://boards.straightdope.com/t/race-differences-in-average-iq-are-largely-genetic/623236 "2012-05-27T12:28:24Z")\ **Posts on this page:** 20\ **Page:** 30
**Author:** ![New\_Deal\_Democrat](https://avatars.discourse-cdn.com/v4/letter/n/9d8465/32.png) [@New\_Deal\_Democrat](https://boards.straightdope.com/u/New_Deal_Democrat)\ **Post date:** [June 19, 2012, 4:39pm UTC](https://boards.straightdope.com/t/race-differences-in-average-iq-are-largely-genetic/623236/581 "2012-06-19T16:39:47Z")
> [@tomndebb](#): > > When I see evidence that psychometry is not simply a way for a group of college professors to get grants, I will give it some thought. So far, all the evidence that I have seen is based on what I consider false reasoning that is, itself, simply begging the question. I do not doubt that we can invent tests that measure “IQ,” meaning we can devise a test to group people according to the way that they answer those tests, but I have seen nothing that indicates that taking a couple of examples of demonstrated intellignce and graphing them actually addresses the entire issue of more complex issue of intelligence. It is an alluring field of study–and one that can be lucrative–but its foundation is not established as reality. As long as what Charles Murray wrote in his essay, “The Inequality Taboo,” remains the truth: “The Orwellian disinformation about innate group differences is not wholly the media’s fault. Many academics who are familiar with the state of knowledge are afraid to go on the record. Talking publicly can dry up research funding for senior professors and can cost assistant professors their jobs,” it cannot be said that there is a candid discussion of racial differences. Public statements by credentialed experts will deserve to be viewed skeptically if they repeat liberal platitudes that race is a social construct, IQ tests measure noting important, and so on. [http://www.bible-researcher.com/murray1.html](http://www.bible-researcher.com/murray1.html) ---
**Author:** ![iiandyiiii](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/iiandyiiii/32/7924_2.png) [@iiandyiiii](https://boards.straightdope.com/u/iiandyiiii)\ **Post date:** [June 19, 2012, 4:44pm UTC](https://boards.straightdope.com/t/race-differences-in-average-iq-are-largely-genetic/623236/582 "2012-06-19T16:44:16Z")
> [@New\_Deal\_Democrat](#): > > As long as what Charles Murray wrote in his essay, “The Inequality Taboo,” remains the truth: “The Orwellian disinformation about innate group differences is not wholly the media’s fault. Many academics who are familiar with the state of knowledge are afraid to go on the record. Talking publicly can dry up research funding for senior professors and can cost assistant professors their jobs,” it cannot be said that there is a candid discussion of racial differences. Public statements by credentialed experts will deserve to be viewed skeptically if they repeat liberal platitudes that race is a social construct, IQ tests measure noting important, and so on. > > [The Inequality Taboo, by Charles Murray](http://www.bible-researcher.com/murray1.html) So it’s a conspiracy, then. Well, it’s a conspiracy against a “side” with an unscientific, incoherent, and non-discrete classification of “race”, zero genetic data regarding intelligence, and an apparent willingness to disregard any evidence that counters their own assertions (like [this](http://www.nature.com/nature/journal/v464/n7290/fig_tab/nature08976_F3.html) phyogenetic tree). One doesn’t need much of a conspiracy to demonstrate the absurdity of such weak arguments. ---
**Author:** ![New\_Deal\_Democrat](https://avatars.discourse-cdn.com/v4/letter/n/9d8465/32.png) [@New\_Deal\_Democrat](https://boards.straightdope.com/u/New_Deal_Democrat)\ **Post date:** [June 19, 2012, 4:44pm UTC](https://boards.straightdope.com/t/race-differences-in-average-iq-are-largely-genetic/623236/583 "2012-06-19T16:44:27Z")
> [@MrDibble](#): > > How does that square with US Blacks who have \>50% European admixture? > Oh, yeah, I forgot - 1 drop rule, right? It is more like 20 percent on the average. That explains why American blacks have average IQs of 85, while African blacks average 70 percent. ---
**Author:** ![Gyrate](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gyrate/32/3588_2.png) [@Gyrate](https://boards.straightdope.com/u/Gyrate)\ **Post date:** [June 19, 2012, 4:49pm UTC](https://boards.straightdope.com/t/race-differences-in-average-iq-are-largely-genetic/623236/584 "2012-06-19T16:49:04Z")
> [@New\_Deal\_Democrat](#): > > “Many academics who are familiar with the state of knowledge are afraid to go on the record. Talking publicly can dry up research funding for senior professors and can cost assistant professors their jobs,” Funny - that’s pretty much what the climate change deniers say too. And the Truthers. And the Moon Hoaxers. And the anti-vaxxers. Fine company you’re keeping. ---
**Author:** ![iiandyiiii](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/iiandyiiii/32/7924_2.png) [@iiandyiiii](https://boards.straightdope.com/u/iiandyiiii)\ **Post date:** [June 19, 2012, 4:49pm UTC](https://boards.straightdope.com/t/race-differences-in-average-iq-are-largely-genetic/623236/585 "2012-06-19T16:49:06Z")
> [@New\_Deal\_Democrat](#): > > while African blacks average 70 percent. I assume you mean an IQ of 70, not 70 percent. But anyway, there is no data for this. Lynn made up the data to give him this “estimate” of 70 as the average IQ for African “blacks”. ---
**Author:** ![New\_Deal\_Democrat](https://avatars.discourse-cdn.com/v4/letter/n/9d8465/32.png) [@New\_Deal\_Democrat](https://boards.straightdope.com/u/New_Deal_Democrat)\ **Post date:** [June 19, 2012, 4:49pm UTC](https://boards.straightdope.com/t/race-differences-in-average-iq-are-largely-genetic/623236/586 "2012-06-19T16:49:18Z")
> [@iiandyiiii](#): > > So it’s a conspiracy, then. Well, it’s a conspiracy against a “side” with an unscientific, incoherent, and non-discrete classification of “race”, zero genetic data regarding intelligence, and an apparent willingness to disregard any evidence that counters their own assertions (like [this](http://www.nature.com/nature/journal/v464/n7290/fig_tab/nature08976_F3.html) phyogenetic tree). The similarities of IQ, even when biological siblings are raised apart, and the persistence of racial differences in average IQ is impressive evidence of genetic causes for intelligence. All that remains is the discovery of IQ genes. Even then people of your persuasion will deny the truth. As time goes on, fewer people will pay any attention to you. ---
**Author:** ![iiandyiiii](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/iiandyiiii/32/7924_2.png) [@iiandyiiii](https://boards.straightdope.com/u/iiandyiiii)\ **Post date:** [June 19, 2012, 4:50pm UTC](https://boards.straightdope.com/t/race-differences-in-average-iq-are-largely-genetic/623236/587 "2012-06-19T16:50:43Z")
> [@New\_Deal\_Democrat](#): > > The similarities of IQ, even when biological siblings are raised apart, and the persistence of racial differences in average IQ is impressive evidence of genetic causes for intelligence. All that remains is the discovery of IQ genes. Even then people of your persuasion will deny the truth. As time goes on, fewer people will pay any attention to you. No one has denied that there is a genetic component to intelligence. But you have absolutely zero data of any tie between any “race” (or even populations) and any genetic tendency towards high or low intelligence. ---
**Author:** ![New\_Deal\_Democrat](https://avatars.discourse-cdn.com/v4/letter/n/9d8465/32.png) [@New\_Deal\_Democrat](https://boards.straightdope.com/u/New_Deal_Democrat)\ **Post date:** [June 19, 2012, 4:51pm UTC](https://boards.straightdope.com/t/race-differences-in-average-iq-are-largely-genetic/623236/588 "2012-06-19T16:51:08Z")
> [@iiandyiiii](#): > > I assume you mean an IQ of 70, not 70 percent. But anyway, there is no data for this. Lynn made up the data to give him this “estimate” of 70 as the average IQ for African “blacks”. Yes, that is what I meant. Lynn used the best data available. It correlates with all the data on racial differences in intellectual performance and ability. ---
**Author:** ![iiandyiiii](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/iiandyiiii/32/7924_2.png) [@iiandyiiii](https://boards.straightdope.com/u/iiandyiiii)\ **Post date:** [June 19, 2012, 4:52pm UTC](https://boards.straightdope.com/t/race-differences-in-average-iq-are-largely-genetic/623236/589 "2012-06-19T16:52:15Z")
> [@New\_Deal\_Democrat](#): > > All that remains is the discovery of IQ genes. Yes, all that remains is for you to actually have evidence of what you assert. Right now you have zero. > [@](#): > > Even then people of your persuasion will deny the truth. As time goes on, fewer people will pay any attention to you. As time has gone on, fewer and fewer people hold to your racist ideals. Do you have evidence that this trend is reversing? ---
**Author:** ![New\_Deal\_Democrat](https://avatars.discourse-cdn.com/v4/letter/n/9d8465/32.png) [@New\_Deal\_Democrat](https://boards.straightdope.com/u/New_Deal_Democrat)\ **Post date:** [June 19, 2012, 4:52pm UTC](https://boards.straightdope.com/t/race-differences-in-average-iq-are-largely-genetic/623236/590 "2012-06-19T16:52:29Z")
> [@iiandyiiii](#): > > No one has denied that there is a genetic component to intelligence. But you have absolutely zero data of any tie between any “race” (or even populations) and any genetic tendency towards high or low intelligence. As more is learned about genetics it will become increasingly apparent why No Child Left Behind has left most black children behind. ---
**Author:** ![iiandyiiii](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/iiandyiiii/32/7924_2.png) [@iiandyiiii](https://boards.straightdope.com/u/iiandyiiii)\ **Post date:** [June 19, 2012, 4:53pm UTC](https://boards.straightdope.com/t/race-differences-in-average-iq-are-largely-genetic/623236/591 "2012-06-19T16:53:34Z")
> [@New\_Deal\_Democrat](#): > > Yes, that is what I meant. Lynn used the best data available. It correlates with all the data on racial differences in intellectual performance and ability. Lynn had no data for more than half the countries he examined, and had terrible data (like 1 IQ test of 40 school children representing an entire country) for most of the rest of the African countries. No actual scientist could come to any conclusion on such miserable data. Terrible, terrible science. ---
**Author:** ![BrainGlutton](https://avatars.discourse-cdn.com/v4/letter/b/82dd89/32.png) [@BrainGlutton](https://boards.straightdope.com/u/BrainGlutton)\ **Post date:** [June 19, 2012, 5:10pm UTC](https://boards.straightdope.com/t/race-differences-in-average-iq-are-largely-genetic/623236/592 "2012-06-19T17:10:32Z")
[RationalWiki on eugenics:](http://rationalwiki.org/wiki/Eugenics) > [@](#): > > **The absurdity of eugenics** > > Eugenics is _not a valid science_ (just in case the pseudoscience sidebar didn’t tip you off). The most obvious flaw with eugenics is that it conflates phenotypical traits with genotypical traits. Even seemingly “fit” humans (or any species) may carry recessive traits that don’t exhibit themselves but will be passed on. > > While eugenics targeted more than just the “inferior” races (e.g., lower classes, the “feeble-minded,” and other assorted and alleged riff-raff), racial purity was very often an element in eugenecist works. Eugenics drew heavily from various racist and racialist tracts of the period. This concept of “purity” is also flawed in that it creates many of the same problems as inbreeding — a loss of biodiversity can in fact lead to increased susceptibility to disease. > > The extreme reductionism of eugenics often crossed into what is now comical territory. Nearly every social behavior, including things such as “pauperism” and the vaguely defined “feeble-mindedness,” could be traced back to a single gene according to eugenecists. Many works of eugenics recall the similar trend evident in phrenology (indeed, there was some overlap between eugenics and phrenology).[17] > > The development of the field of epigenetics, i.e. heritable environmental factors in genetic expression that occur without change to underlying DNA structures, poses further problems for eugenics. > > While eugenics gained widespread support in the early 20th century even within the scientific community of a number of nations, there was also strong opposition during this period.[18] The biologist Raymond Pearl, for example, once a supporter of the movement, turned against it in the late 1920s.[19] The geneticist Lancelot Hogben argued that eugenics relied on a false dichotomy of “nature vs. nurture” and that it infected science with political value judgments.[20] Clarence Darrow famously denounced it as a “cult.”[21] The Carnegie Institute, which initially funded the Eugenics Record Office, withdrew its funding after a review of its research, leading to its closing in 1939.[22] ---
**Author:** ![Who\_me\_1](https://avatars.discourse-cdn.com/v4/letter/w/958977/32.png) [@Who\_me\_1](https://boards.straightdope.com/u/Who_me_1)\ **Post date:** [June 19, 2012, 5:37pm UTC](https://boards.straightdope.com/t/race-differences-in-average-iq-are-largely-genetic/623236/593 "2012-06-19T17:37:42Z")
> [@New\_Deal\_Democrat](#): > > Yes, that is what I meant. Lynn used the best data available. It correlates with all the data on racial differences in intellectual performance and ability. So data he made up out of whole cloth is better because there was no other data for him to use? > [@New\_Deal\_Democrat](#): > > As more is learned about genetics it will become increasingly apparent why No Child Left Behind has left most black children behind. No Child Left Behind has failed children of every stripe. Why should only black children be mentioned/ ---
**Author:** ![Chen019](https://avatars.discourse-cdn.com/v4/letter/c/f19dbf/32.png) [@Chen019](https://boards.straightdope.com/u/Chen019)\ **Post date:** [June 20, 2012, 8:01am UTC](https://boards.straightdope.com/t/race-differences-in-average-iq-are-largely-genetic/623236/594 "2012-06-20T08:01:25Z")
> [@tomndebb](#): > > When I see evidence that psychometry is not simply a way for a group of college professors to get grants, I will give it some thought. So far, all the evidence that I have seen is based on what I consider false reasoning that is, itself, simply begging the question. I do not doubt that we can invent tests that measure “IQ,” meaning we can devise a test to group people according to the way that they answer those tests, but I have seen nothing that indicates that taking a couple of examples of demonstrated intellignce and graphing them actually addresses the entire issue of more complex issue of intelligence. It is an alluring field of study–and one that can be lucrative–but its foundation is not established as reality. What about when someone suffering the effects of a concussion undertakes a psychometric assessment to see the impact on their information processing? Or psychometric testing to determine if a child has some degree of mental impairment from lead poisoning? Are those measurements of no value? What about neuroscientists looking at the [neurobiological basis of intelligence](http://www.google.co.nz/url?sa=t&rct=j&q=www.yale.edu%2Fscan%2Fgt_2004_nrn.pdf&source=web&cd=1&ved=0CFMQFjAA&url=http%3A%2F%2Fwww.yale.edu%2Fscan%2FGT_2004_NRN.pdf&ei=o4LhT_3GEcbdigfXiJH2Dg&usg=AFQjCNGFOY-TC1Y2uiZ58lno0X0S5DIqpQ) or people looking at [cognitive genomics,](http://infoproc.blogspot.co.nz/2011/08/this-is-video-of-talk-i-gave-at-google.html) and relying on psychometric measures, are they wasting their time? ---
**Author:** ![MrDibble](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mrdibble/32/114_2.png) [@MrDibble](https://boards.straightdope.com/u/MrDibble)\ **Post date:** [June 20, 2012, 9:09am UTC](https://boards.straightdope.com/t/race-differences-in-average-iq-are-largely-genetic/623236/595 "2012-06-20T09:09:37Z")
> [@New\_Deal\_Democrat](#): > > It is more like 20 percent on the average. I wasn’t asking about the average. ---
**Author:** ![Chuck11](https://avatars.discourse-cdn.com/v4/letter/c/96bed5/32.png) [@Chuck11](https://boards.straightdope.com/u/Chuck11)\ **Post date:** [June 20, 2012, 6:46pm UTC](https://boards.straightdope.com/t/race-differences-in-average-iq-are-largely-genetic/623236/596 "2012-06-20T18:46:53Z")
I contend that the Black-White US gap is probably more genetic than not. My argument would be that: (1) Contrary to the claims of some, the behavioral genetic default is that the gap is probably more genetically conditioned than not. That is, were we to treat “African-Americans” as an arbitrary sub-population within the American population (e.g., “people who pick their noses in public” or “people who went to community college” ), given the heritability of IQ in the American population and given the magnitude of the deviation, we would conclude: more nature than nurture. (2) The data is not inconsistent with a partial genetic hypothesis (i.e., 50/50 nature/nurture). If you can find an inconsistency name it. (3) The data is not obviously consistent with any known 100% environmental explanation. If you know of one that can be reconciled with the facts, name it and we will discuss. (4) Contrary to the claims of some, there have been studies which have linked genetic differences to race differences. [For example](https://lesacreduprintemps19.files.wordpress.com/2012/05/rowe-and-cleveland-academic-achievement-in-blacks-and-whitesare-the.pdf). ---
**Author:** ![Great\_Antibob](https://avatars.discourse-cdn.com/v4/letter/g/e47c2d/32.png) [@Great\_Antibob](https://boards.straightdope.com/u/Great_Antibob)\ **Post date:** [June 20, 2012, 7:02pm UTC](https://boards.straightdope.com/t/race-differences-in-average-iq-are-largely-genetic/623236/597 "2012-06-20T19:02:49Z")
> [@Chuck11](#): > > I contend that the Black-White US gap is probably more genetic than not. My argument would be that: That’s all well and good, but it still misses out on the fundamental problem of the OP: there’s no actual genetic evidence. It also misses the point in other ways. Saying a genetic component is “not inconsistent” with existing data is radically different from asserting absolute proof, which is what the OP has done. It makes for at least a plausible hypothesis, but what most of us have been clamoring about (for several weeks now), is that there’s no actual genetic proof linking intelligence to race. Even the study you link hand-waves away the idea that American cultural conditions may have an impact (much like the OP does). Also, it contradicts findings from other countries that show no such racial achievement gap in their own kids. Basically: what’s different about blacks in America vs blacks in Germany or the UK that we produce such an achievement gap while they don’t? ---
**Author:** ![Chuck11](https://avatars.discourse-cdn.com/v4/letter/c/96bed5/32.png) [@Chuck11](https://boards.straightdope.com/u/Chuck11)\ **Post date:** [June 20, 2012, 7:10pm UTC](https://boards.straightdope.com/t/race-differences-in-average-iq-are-largely-genetic/623236/598 "2012-06-20T19:10:18Z")
> [@Who\_me\_1](#): > > No Child Left Behind has failed children of every stripe. Why should only black children be mentioned/ A specific goal of NCLB was to close the gap. Its failure indicates that the gap is not due to those factors which were successfully addressed. More informative, though, is the failure of early intervention programs. Here is Nathan Brody’s 1992 discussion of this: > [@](#): > > Is it possible to increase intelligence by changing the early intellectual environment of the child? Research on this topic was influenced by the development of Project Head Start, which was an attempt to provide an enriched environment for pre-school aged children whose impoverished background was assumed to place them at risk of inadequate intellectual development. It was assumed that the provision of superior childhood education for these children would increase their intelligence and increase their ability to cope with the educational program of the public schools….Perhaps the best summary of the outcomes of these studies was published by a consortium formed for the amalgamation of this body of research [Consortium for Longitudinal Studies, 1983]. The Consortium included 14 investigators whose initial samples included 100 or more subjects who were engaged in a longitudinal investigation of the effects of early educational intervention. The samples included in these studies were predominantly black preschoolers which a median IQ of 92 at the times of entry in the program and mothers with a median number of years of education of 10.4. They were predominately of lower socioeconomic status. The results of these studies as summarized by Royce, Darlington, & Murray [1983] are reasonably consistent. Seven studies used IQ as a dependent variable. They obtained a clear increase in IQ as a result of participation in HeadStart. The median IQ benefit at the conclusion of these projects was 7.42 points. Three or four years after the conclusion of these projects the median difference between the experimental and the control group declined to 3.04 points. The last reported assessment includes Wechsler test scores for program participants aged 10 to 17. These assessments occurred 7 to 10 years after the conclusion of the educational intervention. Pooled over a subset of these investigations there was no significant difference between experimental and control groups. Although program children started first grade with an average IQ that was 5.80 points higher than the control group children, these differences were not maintained. Other reviews of early intervention studies based on Head Start reached the same conclusion as the Consortium for Longitudinal studies. There are no enduring changes in intelligence tests scores associated with participation in this program … > > […] The failure of attempts to increase intelligence by early childhood intervention may be attributable to the relatively brief duration of these programs. It is possible that interventions that continued into the first few years of schooling would lead to more enduring changes in performance on intelligence tests. Project Follow Through was designed to extend Head Start interventions in order to obtain more enduring changes. The interventions were based on quite different intervention models. A comprehensive evaluation of the Follow Through Programs compared 22 different intervention models [.] Spitz (1986) evaluated the changes on the only test of intelligence used in these studies — the Ravens. For 107 comparisons that were available where children assigned to Follow Through Programs were comparable to their untreated controls, he found 5 significant difference in favor of groups assigned to the intervention, 11 significant differences in favor of groups not provided with intervention, and 91 comparisons in which there were no significant differences….These data indicate that intervention extended into the first year or two of elementary school will not lead to enduring changes in intelligence test performance. Brody, 1992. Intelligence.) You can check out the most recent meta-analytic results [here](http://www.gse.uci.edu/docs/Leak_Duncan_Li_Timing_Paper_APPAM_102810.pdf). The failure of EE to make lasting improvements for Blacks suggests that the difference, by adulthood, is not due to early environments, no? Well, what is it due to? ---
**Author:** ![tomndebb](https://avatars.discourse-cdn.com/v4/letter/t/b9e5f3/32.png) [@tomndebb](https://boards.straightdope.com/u/tomndebb)\ **Post date:** [June 20, 2012, 7:14pm UTC](https://boards.straightdope.com/t/race-differences-in-average-iq-are-largely-genetic/623236/599 "2012-06-20T19:14:28Z")
> [@Chuck11](#): > > (4) Contrary to the claims of some, there have been studies which have linked genetic differences to race differences. [For example](https://lesacreduprintemps19.files.wordpress.com/2012/05/rowe-and-cleveland-academic-achievement-in-blacks-and-whitesare-the.pdf). That has to be one of the silliest things I have seen, here. Testing for differences between siblings, they found that in both black and white families, there was a high degree of correlation regarding test scores. So what? People in the same families are liable to have similar outcomes. Boy, is that a surprise. (Note: I am not challenging the actual survey that seems to be attempting something different. I am noting that extrapolating from that survey to a reason behind the variance in perceived racial populations is baseless since the survey fails to provide anywhere nearly enough information to make that conclusion. Even in the survey, the method used to identify “nature” vs “nurture” factors is little more than mathematical gamesmanship that really proves nothing, but I will let that pass.) ---
**Author:** ![New\_Deal\_Democrat](https://avatars.discourse-cdn.com/v4/letter/n/9d8465/32.png) [@New\_Deal\_Democrat](https://boards.straightdope.com/u/New_Deal_Democrat)\ **Post date:** [June 20, 2012, 7:26pm UTC](https://boards.straightdope.com/t/race-differences-in-average-iq-are-largely-genetic/623236/600 "2012-06-20T19:26:28Z")
> [@Chuck11](#): > > A specific goal of NCLB was to close the gap. Its failure indicates that the gap is not due to those factors which were successfully addressed. More informative, though, is the failure of early intervention programs. Here is Nathan Brody’s 1992 discussion of this: > > You can check out the most recent meta-analytic results [here](http://www.gse.uci.edu/docs/Leak_Duncan_Li_Timing_Paper_APPAM_102810.pdf). The failure of EE to make lasting improvements for Blacks suggests that the difference, by adulthood, is not due to early environments, no? Well, what is it due to? Just about everyone knows the answer to that question. The fact that it is dangerous to answer the question truthfully and publicly demonstrates that political correctness has inhibited intellectual freedom more than the McCarthy Era ever did. [Previous page](https://boards.straightdope.com/t/race-differences-in-average-iq-are-largely-genetic/623236.md?page=29) [Next page](https://boards.straightdope.com/t/race-differences-in-average-iq-are-largely-genetic/623236.md?page=31)