Open thread 8/1/2012

By Razib Khan | August 1, 2012 12:00 am

The nature of the restrictions of the comments are relatively free-form on this post. You should maintain some decorum as usual. But you can post links, ask me or other readers questions, etc.

  • Ed

    Any updates on the Malagasy genome project?

    Also have you read this study? And your thoughts on it if you have.

    (Found it on this post, btw)

  • B.B.

    Does anyone know of any good studies on the negative effects of being raised in a single-parent home that isn’t a blatant example of what Arthur Jensen has termed “the sociologists fallacy”?

  • Rimon

    Razib -I totally respect your wanting to keep the comments free of inane bs, but I was wondering if it would be possible to have a like button on your posts and also on the comments? This might fulfill a need many of your readers have to participate in the discussion without actually commenting if they don’t have something worthwhile to say. Just a thought! I have no idea if this commenting program evens allows this feature.

  • Dedalus

    Doesn’t your question establish an up-front bias that you are interested more in verifying “negative effects” than in learning if there are different effects?

  • Karl Zimmerman

    Do you have any thoughts on Ron Unz’s essay in The American Conservative this month, taking to task some of the more extreme elements of IQ determinism?

    I always found attempts to compare IQ across different development levels rather odd, quite honestly, because it stands to reason that the Flynn Effect won’t operate at the same speed (or indeed, always go in one direction) when comparing cultures with different levels of technological mediation and socio-economic development. That’s not to say that the entire IQ difference between the developing and developed world has to be due to this, but given we can’t even quite ascertain what the Flynn Effect is yet, it’s probably impossible to correct for, thus international comparisons (except perhaps with countries with similar levels of development) are probably worthless.

  • Sandgroper

    For side interest, a few 2011 demographic data for Hong Kong:

    Fertility rate for permanent residents 1.2
    Life expectancy male 80.5, female 86.7
    Gender ratio 876 males/1,000 females. If foreign contract workers (who are mostly female) are excluded, the gender ratio becomes 948 males/1,000 females.

  • Razib Khan
  • Razib Khan

    Any updates on the Malagasy genome project?

    it had to be put on hold for a bit.

  • Razib Khan

    but I was wondering if it would be possible to have a like button on your posts and also on the comments?

    hey, i want a like button too!!! that’s contingent on a site redesign, etc., which i’ve heard is in the works. but when it comes to IT/design issues be careful of any timetable i give you, that’s a lie :-)

  • Razib Khan

    Do you have any thoughts on Ron Unz’s essay in The American Conservative this month, taking to task some of the more extreme elements of IQ determinism?

    yeah, people have asked about this. i’m more ‘hereditarian’ than most, but i think there is noise in the data. is it just noise? or are there systematic patterns? i’ve long wondered about residuals from trendlines. re: intra-european differences, a deeper exploration of americans might be of interest.

    #6, TFRs for cities are low as a whole. urbanization has been used as one model for why worldwide TFR has been dropping….

  • pconroy

    @5 Karl,

    I read Ron Unz essay on IQ, and noted that he mentioned the Inductivist Blog, and also compared the IQ of Mexicans to the Irish of yesteryear.

    I think I must have inspired this article after he read my back-and-forth comments on this Inductivist post, and my link to an earlier post on

    Helmuth Nyborg interviews Richard Lynn – from 05/31/12

  • Razib Khan

    dziebel seems to forget that i’m the target of attacks by creepy net-nazis and unhinged leftists on a regular basis, so he’s weak tea….

  • amboni

    Does anyone know how typical British Asian writer Kia Abdullah’s appearance (I mean the ‘orientalness’) is in Sylhet?

  • Kosmo

    I’m curious about your thinking in regard to the lack of archaic MtDNA in modern human populations. With evidence for the diversity of ancient admixture mounting all the time, (Neanderthals, Denisovans, and now various African archaics) it seems that chance loss of archaic MtDNA haplotypes is less and less likely, and selective pressure must be invoked to explain their absence in living people. (Perhaps some selective advantage conferred upon haplogroup L and conserved in all daughter haplogroups thereafter– leaving all pre-L haplogroups relegated to the dust bin of history) If selection is a major force at work in MtDNA, does that not destroy the reliability of the clock?

  • ackbark

    Anyone else think the picture of Benjamin Franklin on the current $100 bill is particularly sour looking? Like, ‘I know you’re wasting this money, if you weren’t an idiot you’d do something wise with it but I know that you are not because I can see that are wasting it as you have wasted all your previous $100 bills. . .’

  • Razib Khan

    #14, i wonder as methods for autosomes get better and better we’ll stop using uniparentals for deep time studies. the other option could be that HVR is too mutable, and there’s convergence. so most lineages are extinct, period, and the coalescent just happens to not have the archaic branches.

  • Sandgroper

    “dziebel seems to forget that i’m the target of attacks by creepy net-nazis and unhinged leftists on a regular basis”

    I was googling and saw some of that by accident once, maybe an early form of it – virulent white supremacist stuff. German Dziebel is not in the same league. If he chooses to try, he will find that Razib is not alone.

  • Razib Khan

    #17, i don’t think dziebel’s a sociopath, as many net-nazis are. he has a job, first of all. rather, he seems to have a inordinately high self-regard for himself. notice that he’s a repeated ‘name-dropper’ from his stanford days. if i was really interested i’d email people like joanna mountain and see what they thought of him, if he even remembers them.

  • AllenM

    Reading Unz’s mess made me read it a few times.

    One of the most interesting teases was the growth in Mexican IQ shown in Inductivist’s data, compounded with his mess of conflicting European data. Given that overall height of the children of the recent immigrant populations are significantly higher in almost every study, should not that same nutritional bias stand in IQ?

    One of the most interesting comparisons that could be done would be to also look at the height of those populations (which is really just a comparison of total nutritional success). I would imagine as diets have improved, especially through the use of enriched starches and vitamins, we now are quite confident that overall generational height increases. So, as nations transition to the modern diet, the increased nutritional environment most likely increases IQ as shown. With the nascent inter-generational effects of nutrient scarcity now being shown through studies, why should we expect that overall intelligence of a people to be unrelated to their nutritional status- including the nutritional status of their preceding generations?

    In short, while genes are being revealed as a significant determinant of IQ, nutrition of the children, and most likely of the preceding generations may have a significant role to play in differences.

  • Kosmo

    Razib, in regard to the missing MtDNA, I agree that Occam’s razor used to side with the idea that “the coalescent just happens to not have the archaic branches,” rather than invoking some special selection.

    But with the new studies that have come out recently, I wonder if thinkers in the field have had time to notice that the razor now seems to cut the other way. I claim no special insight, but with each new discovery of admixture, the odds go down that the archaic haplotypes were lost due to chance, again and again, while only the L-derived haplotypes were retained. Given selective neutrality, you could argue that somewhere close to 8% of Island New Guinea should have pre-L MtDNA. 4% of Eurasia. And now these new studies about African archaic admixture reveal yet further instances where L-derived haplotypes rose to 100% frequency at the cost of all other variants which admixture analysis, and an assumption of neutrality, tell us should likely be there. Chance could certainly account for the loss of certain mitochondrial lines within populations, but we must remember that each of these is a distinct case, so we must also consider the liklihood that they would happen lose exactly the same lines. I think Occam’s razor sides with selection now.

  • pconroy

    @19 Allen,

    Yes, I agree with this – nuitrition status is an important consideration. Afterall, it’s been shown that mother’s who are pregnant during famines have children who are moderately retarded – there was a Dutch WWII study some time back.

    Also, there are such things as parasite load, that could have a similar effect as nutritional insufficiency.

    I also take umbrage at the fact that Unz compared Mexicans to Irish, as all both groups have in common is that they are/were nominally Catholic in religion – so no real basis for comparison.

  • AllenM


    I would not take umbrage at the comparison. I would further comment that the lower IQ from rural populations would reflect more homegrown food, which might have deficiencies in nutritional content- these deficiencies would most likely have a large effect on the height and IQ of the total population.

    In short, there really is no point in trying make statements about the true differences of IQ between national populations without some sort of nutritional variance accounting. The difference in the Dutch over a century is stunning in height and well documented. The further nutritional data comparison relied upon in the article showing the comparison to East and West Germany further might have the nutritional background for the differences.

    In short, the extremely sloppy IQ comparisons are drowning in a viable alternate explanation- nutrition, and until modern diet is fully exposed for at least two generations (enrichment was done in the USA in the 1930s), no meaningful IQ comparisons are going to be driven from scant data.

  • Solis

    Have you taken a glance at Richard Lynn et al.’s new book?

    (If it says the website isn’t secure just ignore that part.)

  • Razib Khan

    #23, no. kudos for it being online like that! re: psychometrics, i don’t pay much attention to it anymore because i’ve got a coarse model in my head, and finer grained elucidations aren’t too interesting to me right now. but who knows what the future holds?

  • pconroy

    @22 Allen,

    I agree that cross-national IQ comparisons can/should only be don’t against populations of similar nutritional background – and like you said for at least 2 generations beforehand.

    The other thing you can do is of course to compare nationals from other countries who have emigrated to the US a few generations ago, and see how they compare. One of the difficulties with that though is that often the immigrant group is non-representative of the main homeland population. e.g. Low SES Mexicans vs High SES Cubans etc.

    Lynn’s idea that the Irish had an IQ of about 1 sd below the British mean is of course nonsense, and British and Irish are very much mixed together. On almost all autosomal plots, Irish and British are similar – and in fact the Irish appear as a subset of British diversity. It would be like saying North Koreans have an IQ of 1 sd below South Koreans – after controlling for nutrition.

    Another thing that Unz got wrong IMO is that he bought my idea that rural populations have a lower IQ on average than urban populations, of the same ethnic group – but then he accepted Lynn’s assertion that this does NOT hold true in rural China?! I’m on record – from the beginning of GNXP – as not believing that Chinese IQ – as measured by Raven’s Progressive Matrices in elite schools in Shanghai – is a valid proxy for rural Chinese IQ. I see no evidence for this anywhere. Lynn himself stated in one of his works that London’s IQ was a few points higher than the overall British IQ, due to higher IQ types flocking to major urban centers. The way I see it, if rural, malnourished Chinese peasants have an IQ of say 107, then what Lynn is actually saying is that if we control for nutrition, their IQ might actually be 120 or so – obviously ludicrous!

  • Ed

    What about exposure to infectious disease?

    “We tested all these ideas. In our 2010 study, we not only found a very strong relationship between levels of infectious disease and IQ, but controlling for the effects of education, national wealth, temperature, and distance from sub-Saharan Africa, infectious disease emerged as the best predictor of the bunch. A recent study by Christopher Hassall and Thomas Sherratt repeated our analysis using more sophisticated statistical methods, and concluded that infectious disease may be the only really important predictor of average national IQ.”

    Not saying that it really is the “only really important predictor”, but probably at least an important one.

  • AndrewV

    Anyone know if this is a 1st?

    A virology blogger has been referenced in a PubMed paper titled “Recombinant origin, contamination, and de-discovery of XMRV.”

    Link here:

    Quote (with links defanged to avoid the spam catcher):

    Treatment of CFS patient PBMCs with 5-azacytidine was omitted from Lombardi et al. paper

    In September 2011, Abbie Smith, a graduate student and virology blogger, (// revealed that Dr. Judy Mikovits, the corresponding author of the Lombardi et al. study, presented a figure at a meeting that turned out to be identical to one in the original paper, but with different patient numbers and experimental conditions (John Cohen, ScienceInsider, //

    This revelation led the authors to concede that the patient-derived PBMCs in Lombardi et al. had been treated with 5-azacytidine, an agent used to demethylate DNA and induce transcription from latent genes and proviruses, but did not include this treatment in the paper because “it was not germane.” The omission of such critical information from the paper cast further doubt on the validity of the entire study.

  • Grey

    @Shashi (if you’re reading)

    On a previous post you said

    “In Hindu society there is a concept of a “Gotr” which is basically a clan of people who have descended from a common male ancestor (sometimes mythical). I think the above statement fits pretty well with how the orthodox population sees matrimonial alliances on a greater scale. In North India, you hear about honor killings of sons/daughters often over the fact that they were of the same ‘gotr’. Something similar is popular as well in South India (at least in Telegu and Tamil anecdotally) where marrying cousins from the matrilineal side is a ‘good’ thing. Actually, it’s a lot more complicated than that, and I don’t know if anyone cares to know.”

    I didn’t want to say in a non-open thread but i’d be very interested in this.

  • Bram Hessels

    Maybe introgressed genes caused the Human Revolution.

  • tt9j

    @14, 20;
    The simplest explanation for lack of archaic mtDNA haplotypes is that the successful archaic introgression was male-only (hence no mitochondria transmitted).

    What do you think about mt haplogroup ‘coalescence’ age estimates and the tremendous numbers of mitochondria per mature oocyte? How many dozens/hundreds of generations would it take for any new mutation to ‘surface’?
    Here’s a relevant abstract:

  • Karl Zimmerman

    19 –

    On the question of nutrition, note that East Asians were much shorter 2-3 generations ago (hell, there was some famine during the Great Leap Forward), but their IQs weren’t much lower. Maybe the strange results for East Asians (whereby further development doesn’t seem to raise their IQs much) is because they have genes which favor brain development in childhood even when resources are scarce. Conversely, they could have lost a gene which shunted calories away from the brain in times of comparative hunger.

    If East Asian origins were in very cold area of southern Siberia it’s easy to see them going through an evolutionary “trauma” where they endured a long-term period of hunger but top-notch intellectual skills were still heavily needed in order to survive. Of course, since Siberians and Native Americans probably sprung from the same source, you’d have to argue why they don’t show the same dynamics.

  • Karl Zimmerman

    Oh, and in reply to 6, this looks ominous for China.

  • Kosmo

    @30, male-mediated admixture would fit the data. I’m still skeptical because that would be the opposite configuration that we see in every historical case of population replacement. There is lots of Native American MtDNA in Brazil, for example. Not a lot of Native American Y-chromosomes though. Still, it can’t be ruled out.

    I don’t know what the answer is in regard to the lack of archaic MtDNA, but with each new discovery of admixture, it looks more like a mystery that needs some explanation.

  • Contemplationist

    I’d love your thoughts on the demise of Medical Hypothesis under Bruce Charlton, including what you thought of the enterprise.

  • Shashi

    @28 Grey.

    I realized that you can actually look up the concept on wikipedia it’s transliterated as Gotra from the hindi word gotr or sanskrit gotram.

    I missed out typing crucial words in the previous post. The honor killings happen when families discover that their children are involved in a relationship where both partners belong to the same same ‘gotra’. I hope that did not confuse you earlier. If you want to discuss my personal insights or observations (which aren’t a very deep or enlightening) then we can, but I think the wiki is a pretty good primer.

  • Karl Zimmerman

    33 –

    You appear to be approaching this with the idea that archaics roughly had the modern day capabilities and behavior, which may not be a safe assumption.

    Let’s say the archaics didn’t have language as an extreme example. In that case, there could be no peaceful intermingling of genes. Virtually all cross-population liaisons would be rape. AMH males would father children into archaic, pre-language communities, which were ultimately doomed. Archaic males raping AMH women, in contrast, would get their DNA into our gene pool.

    Of course, the rankle is if archaics were pre (or had incredibly limited) language, you might expect there would be a heavy selection pressure against the hybrids. However, it’s possible that the capacity for advanced language developed before language itself – that the “Great Leap Forward” (which is often linked to the development of advanced language) was actually a cultural innovation rather than a biological innovation. This would mean that human-archaic hybrids (along with the odd foundling) would have no particular selective disadvantage in AMH culture.

  • Ron Unz

    @PConroy: 11, 21, 25

    Actually, I happened to stumble across those fascinating Mex-Am Wordsum-IQ trends on the Inductivist blog several years ago, and don’t think I ever noticed your own discussions on Irish IQ, on GXNP or elsewhere. I’ve been familiar with the very low Irish IQ data which Lynn presented for at least seven or eight years, and had repeatedly pointed these out in various Internet discussions. Consider also that Lynn’s years of personal research in Ireland led him to exactly the same conclusions.

    Regarding high IQs in rural China, I don’t recall Lynn noticing or making such a point. But if you just examine the Flynn-adjusted raw IQ data from East Asian countries, you notice a totally discordant pattern from the low IQs almost invariably found in impoverished or rural European countries, which I think is quite intriguing.

    Another interesting point I made is that during the 1920s, immigrant children from a Southern or Eastern European immigrant background in the U.S. almost invariably had very low IQs, generally 80-85 with white-mainstream children being around 100. However, Chinese and Japanese immigrant children generally scored at 100 or even above, despite all the same difficulties of poverty, rural status, cultural, etc. I find this also very intriguing.

    Finally, consider that the director of PISA has described absolutely remarkable scores coming from impoverished rural China, although these have not yet been officially released.

    The combination of these three factors strongly indicates some unique aspects to East Asian IQ performance, about which I have provided some speculations.

    The follow-up articles which discuss some of these points and more conveniently collected on my personal website, linked to my name.

  • Sandgroper

    #32 – Karl, thanks, I read that and the comments with interest. It’s not the first time that the problem of ageing population combined with the outcome of major gender imbalance in China has been noted, of course, but it’s still interesting.

    I find the labelling of ‘stay at home’ young women who choose to pursue a professional career as ‘parasite singles’ to be beyond bizarre. My own little parasite is welcome to do this as long as she wants – in fact, with her IQ and natural science leaning, if she did not pursue a science-based career it would be a tragic waste. Since the age of 9 and her discovery that she would inherit my tool box when I die, plus the disappointing realisation that this was unlikely to happen any time soon, her basic game plan has been to remain home-based and wait for her parents to die, so she doesn’t have to go to all the trouble of buying her own refrigerator, TV set, etc. She still regards parents + self as “we” in a kind of corporate sense. Of course if she decides one day to get hitched and have a couple of kids, I’ll be delighted, provided she can still pursue personal fulfilment career-wise.

    Part of the explanation for why Hong Kong has such a high population of foreign contract workers is exactly this, of course (and if you back calculate the % of the population from the numbers I gave, it is high) – having a live-in female contract worker at home frees a young woman to get married, have one or two children, and still pursue a professional career. I know any number of young female engineers who are doing this very successfully, and from observation, the kids turn out just fine. 50% of the intake into civil engineering first degree programs in Hong Kong is female (compared to 12% in Australia), which is proving successful because it enables the universities to maintain or even raise the standard of the student intake, and it is happening naturally as female-discouraging factors are eliminated in the work place, without the need to go to some of the ridiculous lengths that are being unsuccessfully pursued in Australia, like issuing the girls with pink-coloured safety helmets and having all-female professional meetings titled ‘girltalk’ – stupid moves which simply propagate a male-female divide within the profession. (Side-note – you don’t need to be a math genius to be a good engineer, just good enough. What has a lot of the males really worried in Hong Kong is that now, most of the top graduates in civil engineering are turning out to be female. The interesting observation to me is that at least some of those top graduates still want to get married and have kids while remaining in the engineering work force, and there is a mechanism in place that enables them to do that, which also benefits poorer south-east asian economies because the contract workers repatriate their savings.)

    Ideologically, I don’t give a rat’s arse what happens to China. From a purely practical, self-interested perspective, I am unable to feel panicky about ageing populations – I simply don’t believe in linear projections, and as populations age, it’s evident that older people’s fitness to remain in the work force is increasing. At least for professionals, the limitation now seems to be brain deterioration, which doesn’t seem to set in, in any really limiting way, at least until into the 70s (he said hopefully). Personally, I’ve tried retirement for a couple of years, and it sucks. I’m back in the workforce and intend to stay that way until the men in white coats have to cart me out in a strait jacket.

  • Eurasian Sensation

    Here’s a question relating to some of the recent posts here on African genetics. Is there any correlation between those speakers of Bantu languages which feature clicks, and Khoisan genes? For example, the Shona of Zimbabwe don’t have clicks but the Ndebele minority do – do they have a greater degree Khoisan ancestry?

  • Sandgroper

    #39 – Seems to be the case in South Africa.

  • Razib Khan

    #39, as #40 said, yes. in SA there is a east-west cline, with the xhosa being most genetically and culturally influenced. and of course the ndebele have origins in south africa, during the ‘crushing’ period of the 19th century, so they are surely likely to have more khoisan than the shona.

  • Kosmo

    36- @ Karl,

    What you describe certainly can’t be invalidated by the data.

    But we may be getting ahead of ourselves. The first step should be to prove that the math has switched sides on the null hypothesis–and an alternate explanation to chance-loss is indeed required to explain the lack pre-L mitochondria. Ultimately, it’s a math problem, so it should be possible to prove which way Occam’s razor cuts. It could be I’m wrong, and no explanation is required, and stochastic processes do provide the necessary statistical spread. Why create complex explanations for the lack archaic MtDNA in modern populations if a simple explanation will do?

    I suspect a statistical analysis could be done to answer this. We just need to know the likelihood of a specific MtDNA line going extinct given x number of generations and y population size. In the case of Neanderthals, given something like a 4% starting frequency, how likely is it that chance alone could remove those haplotypes from the population? This seems like it could be calculated by somebody with the math chops to do it. (not me, alas) I suspect the answer would be that it is reasonably likely. Or at least not extremely unlikely. So perhaps there need be no mystery there.

    But then you also need to calculate the likelihood that another 5% of Denisovan MtDNA would happen to drop out of populations in New Guinea. And then you calculate the odds that all pre-L MtDNA would happen to drop out of the admixed African populations. And you have to multiply those odds together to get the likelihood that chance alone would remove all the pre-L haplotypes. And for each new discovery of admixture (the paper I read said the models predicted something like 9?) you have to keep multiplying. It doesn’t take long before the odds get pretty slim that chance alone could explain it.

    Each new instance of admixture is it’s own spaceship into the future, and we’re the aliens comparing the different colonies a thousand generations later. In any one colony, you might expect to lose a given mitochondrial line if it only starts out at a 5% frequency. But given enough colonies, those rare older clades should pop up somewhere. So far at least, they haven’t.

    Razib, feel free to tell me I’m on crack. I’m very open to just being plain wrong in my thinking, and I’ll just slink away.

  • Grey



  • Andrew Lancaster

    @14 (and reply 16) Despite their obvious problems, uniparental markers should probably continue to be discussed concerning timing of ancient movements of people, just in a more limited way. The reason is that they represent a real line of descent and branching, not a soupy mix. And these family trees can at least occasionally be compared to things like languages, historical events, and of course autosomal DNA.

    For example, certain important movements of people are of small elites. These will be hard to spot in autosomal data, but consider how one haplogroup can suddenly come to be dominant in even a populated continent (R1b in western Europe; E-M81 in NW Africa). It may or may not be that the same patterns will be reflected in the same way by automsomal analysis.

    When autosomal, Y DNA and mtDNA show different patterns, this is always really interesting in itself.

  • miko

    @42 “It could be I’m wrong, and no explanation is required, and stochastic processes do provide the necessary statistical spread.”

    I think this has been discussed on this blog, but yes. There is no explanation required for neutral loci to be lost. The vast majority of individuals have no descendants on a long enough time scale. Mitochondrial Eve, Y Chromosome Adam, and Any Locus Steve move forward in time. Losing all direct female line descendants of our potential female Hsn ancestors is not particularly unlikely — there aren’t that many haplogroups around today at any locus. Same with Y. There are not “many” examples of archaic admixture in the context of total Hs gene flow / drift. Chance doesn’t account for “some” loss, it accounts for almost all loss, and most things are lost. It is also possible they were selected against, though I don’t think their absence is evidence for this.

  • Karl Zimmerman

    38 –

    1. Despite aging populations being able to work in a white-collar fashion longer than in manufacturing, I’m not sure how this helps China. First, it’s unclear to me that 20 years is long enough for China to transition to a white-collar economy. Secondly, despite blue-collar workers in China arguably being higher in intelligence than elsewhere, they’ll still be hitting their 50s and 60s with manual labor being all they know, which would require extensive retraining.

    2. My wife’s best friend lived in Hong Kong for three years, and I was aware of the huge use of domestic servants there (she was one of the only people who walked her own dog). She is also an engineer who worked with one of the universities in Hong Kong oddly enough. Regardless, there’s something a bit unsettling to me with your conclusion. A nice way to put it is that women can be only fully competitive with men when housework typically considered “outside the economy” in the West is monetized. A less nice way is in order to ensure real gender equality, you need some measure of class inequality.

    42 –

    Of course you’re right and random drift may be the simplest explanation. It’s just that your comment about modern admixture patterns suggested you were falsely using a present-day dynamic to model the past, which could be faulty for many reasons.

    One thing to consider is rare alleles are more likely to go into terminal decline in small populations. Throughout most of human history pre-agriculture, effective population sizes were probably small, because the vast majority of mating would be within an ethnolinguistic group with perhaps a few thousand people at most. Of course there would be events which caused population admixture, such as accepting outsiders, kidnapping wives, etc – but these would generally be rare events, and would only admix those two populations – not the region as a whole. So even if a million people lived in Europe in the Mesolithic, genes (except those under heavy selection) may not drift freely enough from group to group to consider this the effective unit of population.

    Of course, at the present, isolated groups with little outside gene flow can show very high incidence of rare alleles, even ones which hurt fitness to some extent. However, most cases I am aware of are post-agricultural peoples who have at least an order of magnitude more population than a hunter-gatherer ethnicity would. Having a population in the low tens of thousands rather than the thousands may make a big difference.

  • Sandgroper


    1. You never heard of machines? They have in China, now. Plus at 63 I’m now lifting more weight in the gym than I was when I was in my 30s.

    2. You mean you actually know how many people in Hong Kong walk their own dogs? Based on what some friend of your wife said? Wow. I live here now, have done for more than half my life, and I see people walking their own dogs all the time. Want a %? I’d estimate 90% of dogs I see are being walked by Chinese people, maybe 10% tops being walked by foreign contract workers.

    No, you have put words into my mouth. What I was referring to was a woman being able to have a professional career and also have children, which I specifically referred to. Sorry, but I think you have been disingenuous – my intention was obvious. I even said “the kids turn out fine”. To spell it out for you, the point is that the foreign contract worker minds the kids during the day, takes them to school and picks them up afterwards, so that the woman can go to work.

    Maybe you’d consider that child minding centres are class inequality too.

  • Kosmo


    “There is no explanation required for neutral loci to be lost. The vast majority of individuals have no descendants on a long enough time scale.”

    –Agreed. Lets assume, for the sake of round numbers, that 90% of MtDNA lines should be lost due to stochastic processes over the time frame in which these admixture events happened. So that’s 9/10 chance that Neanderthals MtDNA lines get lost. 9/10 chance that Denisovan lines get lost. 9/10 chance that the archaic African lines get lost from Mbuti. But keeping in mind that these are each discreet events, you have to multiply them together to get the total likelihood that all pre-L lines get lost: and suddenly the odds drop to 72.9%. Throw in more more admixture events, and the odds keep dropping. If that paper was correct and mathematical models of autosomes really do indicate upwards of 9 discreet and significant admixture events, the odds would drop to: 38%, given the placeholder 90% chance-loss figure I tossed in there.

    Of course these numbers flex completely around the accuracy of that original 90% figure. If that number is 99%, instead of 90%, it obviously makes a huge difference, and the whole mystery kind of falls apart.

    Karl, thanks for your input.

  • Karl Zimmerman

    47 –

    Apologies if I offended you. I thought you were in Australia from past comments. Probably her expat social network was not representative of Hong Kong as a whole.

    I have no doubt the kids turn out fine with a nanny. The rich have used nannies in the west for generations, and they turn out fine. My unease isn’t for the sake of the children, but a personal distaste I have for some of the trappings of wealth.

    Perhaps due to the left-wing nature of my family (my family literally said all rich people are assholes growing up), I have a strong visceral dislike for the trappings of wealth. Being at a party where private servers are used makes me deeply uncomfortable, as does being in a very opulent personal residence. And even if I’d have the money to hire a professional cleaning person and/or nanny, I wouldn’t want to do so because that’s something the wealthy do.

  • Sandgroper

    Karl, no apology necessary. I was back in Australia for a couple of years. I am no longer, by choice, for a lot of disparate reasons.

    I grew up in a poor family, and I share your dislike of conspicuous displays of consumption. Initially I was also uncomfortable with the idea of having a live-in ‘helper’. That was quickly dispelled – it wasn’t that kind of relationship. In fact, when I first arrived in HK, still young and single and trying to adapt to a new job and a strange environment, my first “amah” knocked on my door, introduced herself, informed me that I was going to employ her, which household duties she would perform, how much I was going to pay her, and what days off I would give her, then breezed past – no discussion, she just kind of took me over. She was Chinese, her husband was a police inspector. Her favourite joke that she never got sick of was that every year on my birthday she would give me a bottle of White Horse scotch whisky, because my adopted Chinese surname means ‘horse’ and I’m ostensibly white – she use to call me ‘big stupid white horse’. This was not a master-servant kind of relationship – basically she ran my life for me until I got married and my wife took over running me.

    The reality is that people in Hong Kong can earn a lot more than people in the Philippines, Thailand, Indonesia and Sri Lanka – a couple both working can afford to pay for a woman from one of those countries to live with them and help out, take care of the kids during the day, such that both husband and wife can pursue careers, and the helper can earn and save a lot more than she ever could in her home country. Maybe that sucks, but as long as those economies stay the way they are, it’s an arrangement that benefits both parties. Some of the women who have worked for us have maintained a friendly relationship with us, and a very fond relationship with our daughter, including one Muslim girl from Indonesia who lived with us – I wasn’t sure how that would work out, but it worked out fine.

  • S.J. Esposito

    33 and 36, there’s also the possibility that progeny born from an AMH males and neandertal females were taken under the care of the neandertal mothers, and thus eventually died off with the rest of them. At the same time, those children born from an inverse pair would have been taken under the care of the AMH mother and survived long enough to reproduce.

  • Karl Zimmerman

    Sandgroper –

    You’re right, it doesn’t sound exploitative.

    The one thing I wonder about, however, is how these women’s own families come into the equation. I have to think being a full-time maid/nanny makes it very difficult for those with small children. Is this labor pool made up almost exclusively of either young women who are not yet parents, or older women with grown children?

    51 –

    This is of course true. However, one would assume that AMH men, provided archaics were behaviorally modern, would sometimes kidnap neandertal (or denisovan, etc) women and return with them (or occasionally pick up “stray” females in non-hostile situations). In that case the hybrids would grow up in AMH youth culture.

    Thus, IMHO, you’d have to assume there’s some reason why adult female archaics would have zero ability to integrate into AMH culture – such as a lack of behavioral modernity. Presuming there was male-only geneflow of course.

  • Sandgroper

    Karl – both, and some with younger children. In the case of women with younger children I think it’s awful, but it’s their choice, they leave them with family and see them when they go back on holidays. If I had been working in civil engineering or mining in Australia, it wouldn’t have been too different for me – I would have been working away from home most of the time and only seeing my family occasionally.

    I would say most are either younger single women or older women whose kids are maybe teenage or older, but I couldn’t guess at numbers.

    I’m not saying it’s always wonderful – you do hear of cases of mistreatment and exploitation, but I’d say in the majority of cases it’s an acceptable relationship to both parties, given the economic realities.

  • Sandgroper

    Karl – sorry, I missed your comment “Probably her expat social network was not representative of Hong Kong as a whole.”

    Yes, that’s absolutely true. They don’t mix.

    The Indians took up playing cricket and became better at it than the British. The Chinese never did.

  • pconroy

    @37 Ron,

    Thanks for taking the time to respond.

    It’s a pity the comments on old – in it’s various incarnations are no more – as I could then refer to them directly.

    I’ve commented on the old many times on IQ over the years, and specifically after Jason Molloy did an extended post, extolling every single chapter, almost paragraph by paragraph, of Lynn’s book as being some sort of masterpiece of science. I challenged the obvious flaws in Lynn’s work, then engaged in a lively debate with a commentator with the handle of “TennisPlayer” (IIRC), who seemed to have intimate knowledge of Lynn’s book and his personal website. When he couldn’t satisfactorily answer my allegation, and instead got into Ad Hominum attacks, I suggested that he was actually Lynn – after which he disappeared completely – so he might have been.

    Anyway, I believe I was the first to use PISA scores as a better proxy to National IQ then those results contained in Lynn’s works – see here:

    In the above linked article, I used PISA scores to prove that much of Lynn’s ordering of IQ scores was erroneous – due mostly to low sampling and different tests being administered in different locations – though the conversation wasn’t about Lynn per se, but rather Israel. You’ll note that Mexico’s IQ and “Smart Fraction” came up too.

    I produced these charts – based on a German researcher’s work:

    Smart Fraction By IQ

    Smart Fraction By Performance

    Also, while Lynn doesn’t specifically say Chinese rural IQ is very high, he uses the IQ of select schoolchildren in Shanghai as the “National” IQ of China – which should include both urban and rural individuals. As much of China’s population are rural peasants, I don’t see how he can make this flight of fancy. However I await the latest PISA scores that you mention as coming from rural China.

    BTW, in your comment you say:
    However, Chinese and Japanese immigrant children generally scored at 100 or even above, despite all the same difficulties of poverty, rural status, cultural, etc. I find this also very intriguing.

    I’m not intrigued by this. For Europeans coming to the US would be like Chinese migrating to Vietnam or further south into Malaysia or Indonesia – in that they were migrating to a similar culture, with similar religions and customs – so there would be a low bar of difficulty to go there. For a Chinese or Japanese person to come to the US would be a high bar of difficulty, much like a European or American from yesteryear going to live in Beijing, Hong Kong or Shanghai – therefore it would select for more able individuals, than not.

    I’m also on the record as stating that I think the Indian IQ is under-measured, due to the massive poverty in that country. IIRC, something like 60% of starving children worldwide live today in India. Rural people under Communism – like in China – often do not suffer such starvation levels. Notwithstanding Stalin’s Ukrainian Collectivation famine, Mao’s Great Leap Forward famine. Plus I’m aware that one of the more progressive states in India – where much of the Tech Outsourcing boom is located – is Karnataka and it’s Communist. Maybe communism in that state, together with minimums of nutrition, lifted it’s average IQ enough to be able to sustain the more cognitively demanding Tech sector work – or maybe there are enough High Caste/Brahmins to go around.

    I’ll take a look at your follow-up articles on your site. Cheers!

  • Sandgroper

    It’s a long while since I looked at anything by Lynn, basically because I concluded his Chinese data were dodgy. It looked like he had taken Hong Kong as a proxy for southern China (which is just wrong) and concluded that ‘southern Chinese’ have higher mean IQ than ‘northern Chinese’ – which is also wrong, or a gross over-simplification, or not even wrong, or whatever. He’s just not rigorous if his grasp is that Hong Kong is an acceptable proxy for Guangdong Province, or Guangzhou, or southern China, or whatever. On the other hand, if he is generalising that Guangdong plus Shanghai = southern China, then it would be no big surprise that they would come out close to the smartest. But that’s not very rigorous.

    Not saying this blogger is right, but I think he’s likely to be less wrong than Lynn:

  • Ron Unz

    PConroy: I challenged the obvious flaws in Lynn’s work,

    Yes, I never spent much time on GNXP, so I’m sure I missed it. What really gets me is that so much of the Lynn data is so totally ridiculous, it’s amazing that there seem to be tens of thousands of webpages out there which quote every last number as absolute Revealed Truth. I’ve probably been pointing out some of the larger absurdities in Lynn for at least six or seven years in various on-line discussions, and nobody ever paid the slightest attention, so I finally decided to write something up.

    As I’ve told people, the biggest single factor which moved me away from believing in something close to “the Strong IQ Hypothesis” was…Lynn’s book. The Ford Foundation should really print up a million copies and distribute them to every college.

    For a Chinese or Japanese person to come to the US would be a high bar of difficulty, much like a European or American from yesteryear going to live in Beijing, Hong Kong or Shanghai – therefore it would select for more able individuals, than not.

    I’m no expert on East Asian immigrants of that era, but I don’t think you’re correct. The historical claims I’ve always read were that most of the Asian immigrants were pretty typical peasants or that sort of thing, who’d just heard about the opportunities from previous relatives (i.e. chain-migration). So perhaps they were a bit above average economically, maybe in the upper half or upper third, but nothing remotely like an elite. Therefore, the 20 point IQ difference with Italian or Greek immigrants really is quite remarkable.

    Sandgroper: It’s a long while since I looked at anything by Lynn, basically because I concluded his Chinese data were dodgy. It looked like he had taken Hong Kong as a proxy for southern China (which is just wrong) and concluded that ‘southern Chinese’ have higher mean IQ than ‘northern Chinese’ – which is also wrong

    Well, I’d certainly agree that Lynn’s China data isn’t too good (and also contains some absolutely crazy personal “adjustments”), but given that he has something like 30 East Asian studies, and almost every single one is 100+, despite horrific poverty, the pattern seems extremely different than what you see in his European data. I’d personally bet a lot that there’s *something* going on, though whether it’s biological or cultural I can’t say.

    And I hadn’t seen Lynn compare Southern to Northern China, but I do think he might be correct. The IQ scores might not be too representative, but don’t forget that China’s had national standardized exams for 1500 years, which provides huge datasets. I remember reading that a couple of the Southern provinces—whose names I forget—have been so strong on those exams for so many centuries, that an official quota system was established to prevent them from completely monopolizing the production of government officials. I’ll bet their PISA scores will be remarkable as well, once they come out.

  • Darkseid
  • Razib Khan


    re: lehrer. my own interactions were fine, if cursory. i wasn’t going to say anything, though i was shocked at what he did. but now i’m kind of pissed at how he threw brendan mahrer under the bus:

    it’s one thing to make shit up, but another to pin the blame on others. i also have to add that the chris of mixing memory, who is out of blogging now, did bring to my attention jonah’s deficiencies as an analyst very early on in 2006. chris’ knowledge of the area of cognitive neuroscience was way higher than mine, so i couldn’t judge at the time, though i took it seriously. but it seems he was right in 2006.

    i hope jonah figures things out though.

  • Sandgroper

    Ron – Yes, that’s pretty much what I’m saying – it’s literally ‘a couple of southern provinces’ (actually a few, very populous ones), which on Slitty Eye’s data (admittedly not a perfect data set) score as high as Shandong in the north east – historically, they would have been swamping the north in the examinations, just on IQ x population. There are a whole lot of other southern provinces which score below the national average, and that would not surprise anyone who has been there. And around Shanghai and the coastal strip from Shanghai up to Shandong scores higher than anyone else. To generalise that as ‘south is smarter than north’ is not right because it leads to misleading conclusions – in reality, Guangdong people are about as smart as Shandong people. There have been huge population movements of people into the eastern and southern coastal cities that were made special economic zones by Deng Xiaoping – it should not be a surprise if those cities turn out to have the highest means.

    What is striking about Slitty Eye’s data is that even the lowest scoring province comes in at above 100. I think that underlines your point. On Paul Conroy’s model, even if the lower scoring ones went to Indonesia because it was less challenging than the USA (hard to imagine), those people were smarter than the average bear.

  • Darkseid

    yeah, I never bookmarked his blog because the analysis was too often a shallow review of the literature but that PT article seems like it’s MUCH worse than i estimated. i always assumed he had a profound understanding of the underlying neuroscience his articles covered but he just chose to express it in a more PopSci way. it seems more like he doesn’t really know much more than what’s in his blog posts – which is not much. oh well, one can learn way more in a shorter amount of time from Kandel or LeDoux anyway.

  • Solis

    Does the higher genetic diversity in sub-Saharan Africans explain why mixed children of blacks + other couples usually look more black than anything?

    As in, the higher number of genetic characteristics overwhelms those of the other parent and allows them to be present in the child.

  • Ron Unz
  • Darkseid

    it’s not “IQ determinism” it’s that your IQ *potential* is determined by your genes. shit, they can even SEE how smart you are by simply looking at your brain now:
    forget all the endless paragraphs of semantics, do you honestly believe that everybody has the same potential intelligence? GWB is as smart as Stephen Hawking? a border collie is a smart as a bulldog as long as they’ve had the same environment? one culture is flying to MARS as we speak and another is still trying to figure out how to pave its roads and your grasping at every excuse you can imagine. it’s embarrassing – you should just stop.

  • AMac


    Your positions on race are being invoked by Jason Antrosio on a post at Cochran’s and Harpending’s blog West Hunter, “Platitude Storm: Race as a Social Construct.” Antrosio’s comments here, and subsequently at 7:33 pm.

    If Antrosio’s writing is straight, Harpending is simply misinterpreting his nuanced and HBD-aware position on race, and the post’s concerns are a tempest in a teapot. Other possibilities also suggest themselves.

  • Spike Gomes

    Wow, this is the first time I’m actually able to provide possible data points for others smarter than me to work with. As part of my Master’s thesis I had to do quite a bit of analysis on Japanese immigration to Hawaii and the United States mainland. I know it’s a bit overly specific, but I hope it helps some.

    Japanese immigrants in the 1880s-early 1900s really represents two separate streams. There was a bulk immigration to Hawaii of mostly peasants from predominately rural areas of three prefectures (Yamaguchi, Kumamoto and Okinawa) to work the sugarcane plantations. They composed the majority of immigrants there. However direct migrants to the mainland USA were much more evenly spread from across the nation and included many urbanites and skilled workers as part of a self-selected stream. Part of this stream did end up in Hawaii, where they ended up being much more predominant in higher occupations such as shopkeepers, publishers and community leaders amongst the Japanese (to the point where it caused tensions within the community due to regional rivalries and linguistic differences).

    More interestingly, many of the more ambitious and entrepreneurial amongst the three dominant group would use their worker’s contracts as a foot in the door to America. When their contract was up, they would go to the West Coast where wages were higher and there was more chances for upward mobility. The ones that did go to the West Coast ended up doing better in the long run on some key indicators. They sent a higher proportion of their children back to Japan for higher education and generally had higher rates of secondary school completion. Also, interestingly, they had a greater sense of ethnic nationalism than the Japanese of Hawaii who had lower rates of Japanese language retention and interest in the Japanese Empire in the second and third generations (though this may be an artifact of a development of a “local Japanese” plantation identity and alienation from the first generation priests and school teachers brought in from Japan who tended to take a low opinion on the “Japaneseness” of Japanese born and raised in Hawaii).

    In Hawaii nowadays, Japanese-Americans do well enough, probably above the general population mean, but they don’t have a “model minority” status. For every doctor, professor and politician, there’s ones that are simply average road crew workers, office drones and farmers. Heck on the neighbor islands there are still communities of rural Japanese-Americans not overly differentiated from the mixed-Hawaiian and whatnot communities around them that have a very blue collar existence where the main hobbies are fishing, pig-hunting and driving around pick-up trucks on huge tires. Lots of the brightest of those communities stay in Honolulu or the mainland after college. I would note in general that Hawaii has a bad problem with brain drain, no matter what ethnicity. Those with the mind and drive often leave here and never look back (as recent American history demonstrates).

  • saman

    Is there any reason to believe that “pygmy” hunter-gatherers have systematically different (what I’m getting at is archeologically discernable) effects on naïve megafaunal assemblages than bigger ones?

    This may be difficult to evaluate because (as has been observed here iirc) “negrito” and “pygmy” phenotypes have been independently converged upon in numerous instances, so in lieu of ancient skeletons it seems like it’s difficult to say whether any particular short-statured group arrived that size or became smaller in situ.

    But maybe weapons are enough of a leveler (we’re not like fish limited by jaw gape) and human body size range not extreme enough for this to be readily evident … though I do wonder about other trophic distinctions — many Philippine negritos seemed to spend a lot of time hunting for frogs.

  • Karl Zimmerman

    Now that the subject has gotten back to the perennial race and IQ…

    I’m wondering what folks think about Judith Rich Harris’s hypothesis in The Nurture Assumption that black-white test score gaps are at least in part due to her group socialization model.

    To recap to those not familiar, she believes that IQ as we age becomes more hereditary, and less environmental, because we seek peers similar to ourselves. Thus kids who might start out with a little trouble in school end up in subcultures which think “studying is for suckers,” which causes them to stop trying hard at all. In black students, there’s the added racial element – students who attempt to excel are claimed to be mocked by their peers for “acting white.” As most young people want to conform to their peers, these group efforts to drag performance down are generally successful anywhere where there are enough black students to form an independent social network.

    Harris interprets this as the reason why the biracial children of U.S. soldiers in Germany showed IQs identical to white children of U.S. soldiers in Germany – they mainly went to schools where they were the only “black” kids, so they had to conform to the dominant (somewhat studious) culture. In addition, they were totally unaware of what an African-American was supposed to do in school.

    In addition, she cites intriguing, but anecdotal, cases where there are two different black ethnicities in a school – African Americans and Haitian/Jamaican Americans. In both cases the latter groups remained relatively studious when compared to the African-American cohort in school – they were derided as “acting white,” but their own social identify formed which distinguished them from “African-Americans” in part by trying hard in school, so the criticism fell on deaf ears.

    I find her arguments highly plausible – probably the best social arguments for gaps in performance I have read. It explains other strange factors which have been noted as well. Like how black adoptees into white families typically start out with high IQs which drop to the mean for the race by high school. As high schools usually have a larger population than elementary or middle school, it’s easy to find a black social cohort to conform to. In addition, the British test scores I saw earlier this year which showed British of African descent closing the gap entirely (while those of Caribbean descent still scored lowly). I spent a year living in Britain, and the two communities do have rather little to do with one another, so such gap is easily explainable by socialization.

    It seems it would be easy to undertake a study to test this part of the hypothesis. Compare IQ, SAT scores, WORDSUM – some measure of intelligence – between black students who went to overwhelmingly black schools to those who went to schools with only a handful of black families. If Harris is right, the latter should score much closer to white students than other black students.

    Of course, this still raises issues, in some ways thornier ones than 100% genetic differences would. It implies that in order to achieve African-American equality, a major portion of African-American culture (or at least, youth culture) needs to be effectively destroyed, with the next generation of children either sequestered from older kids entirely, or sent off in very small groups to overwhelmingly non-black schools. I doubt many would enjoy this solution in the short term, even if it works in the longer run.

  • M87



    If anything I was a little surprised that you thought it was fit to mention Lehrer’s post on the decline effect in one of your posts lately as noteworthy exception to poor science journalism industry (if I can recall correctly)

    To me, this man is dangerous because he demonstrated in that article that he was willing to fabricate things in order to prove his point. More specifically, in order for this thesis to have science-wise applicability, he decided to invent evidence about Physics, the most robust of the physical sciences.

    He wrote that the ‘weak coupling ratio’ of a decaying neutron had fallen by ten sigma. Since my area of relative expertise was Physics and that my instructor for a course that semester was in the team at NIST who study neutron decay, it became instantly clear that this man didn’t know what he was talking about. (in fact, it was in the ‘not even wrong’ category, as what he probably wanted to say was axial vector in the weak coupling constant, which we use to calculate a ration)

    Anyway, no amount of emailing or writing the new-yorker to retract this assault against fundamental science was useful. I remember just being really annoyed with how you can get away with something if it’s cryptic enough and not published to an audience who has any level of expertise or understanding of the subject matter. I wrote to this man again recently, asking him to do the right thing and own up to all the things that he has made up because undoing and erasing the internet’s memory of falsehoods is almost impossible, even if new yorker retracts or corrects something.

    I am just pissed off that it has to be an inconsequential Bob Dylan quote that has caught the publics attention and not the important frauds.

  • Jm8

    Nevertheless, the Afro Carribean- White gap in Britain is substantially smaller than the Black-White gap in the US. And I do not believe Carribean immigrants there were very positively selected, nor are African immigrants nearly as much so as those to the US.

  • Jm8

    The correlation of GSCE English/Maths to iq, and to g particularly, looks to be high.

    “Intelligence and educational achievement” Ian J. Deary

    “Cognitive Abilities Test (CAT) and GCSE grades: 2009/10”

    The Black-White gaps, especially White-African, in English/Maths and Key stage 4 Math/reading exams are small. The Somali-White gap in particular is somewhat larger than the general White- African gap which looks small to non-existant.(See the last source which breaks down Africans, Pakistanis, Europeans and others into more specific groups. )

    “Ethnicity and Education:
    The Evidence on Minority Ethnic Pupils aged 5–16”

  • Karl Zimmerman

    One other thing I considered in terms of race and intelligence regarding Hispanics – even if you take a strict “HBD” perspective on race (which I do not), the IQ scores for Latino groups are a bit too low.

    We now have fairly good estimates on admixture of white/native american/SSA for different Latino groups in the U.S. For the sake of argument, let’s consider the average IQ of the white component to be 99 – the modern Spanish IQ. Let’s consider the average Native American score to be 87 – the mean score of Native Americans. The African component is harder, given scores in Africa are undoubtedly depressed, but European admixture may have added some IQ points in the U.S. The latest admixture estimate I have seen is a mean of 14% European ancestry, so presuming the mean IQ of the European population was 103 (American white mean), the African remainder had an IQ of 82.

    Using these as a baseline, I come up with the following estimates. These are for the population within the U.S., not their home country:

    Mexican – 92
    Puerto Rican – 93
    Cuban – 95
    Dominican – 90
    Central American – 91
    South American – 93

    Mean Latino: 92

    AFAIK, all of these numbers are higher than the means actually reported from either Latinos at large, or those reported from home countries. In the case of Cuba differential migration could theoretically be the difference, but this is unlikely to be the case with the other groups, who are not all that demographically different from those who stayed at home.

    Thus, I’d say honest proponents of HBD need to admit that IQs of Latinos are still somewhat depressed by some environmental/cultural measure, even if they are otherwise straight-up IQ naturists. The only ways around this are either to argue that there was some selection against IQ across Latin America (or Europeans who settled were dumber than the average Spaniards), or that U.S. Native Americans and African Americans had active recent selection towards greater intelligence, which Latin Americans missed out on somehow.

  • Grey

    “Now that the subject has gotten back to the perennial race and IQ”

    If the brain is such a high cost organ then doesn’t it make sense for evolution to select for the minimum level of average IQ needed to survive in a particular environment and as a social animal that would include the effect of the brighter members of the group being able to carry the dimmer ones to a certain extent e.g. through creating adaptive behaviors via culture and/or religion for the dimmer ones to blindly follow

    “The correlation of GSCE English/Maths to iq, and to g particularly, looks to be high.”

    “A-level results 2010: A-level pass rate rises to 97.6%”

    A-levels are the stage after GCSEs and taken around age 18.

    So…98% pass rate.

    Not only has the current version of the British education system eliminated average IQ differences between ethnic groups it has eliminated the differences between individuals as well. They increased everyone’s IQ to the same level!

    So, logically speaking, either they’re miracle workers or the current British education system has been dumbed down to the point where everyone can pass.

  • Karl Zimmerman

    Grey –

    I’ve heard this argument before, and it’s a bit weak.

    At least in studies of modern society, it’s been shown that intelligent men father more children than the average. Intelligent women have low fecundity, but this seems to be a result of modern cultural norms and birth control, thus at best there was probably no selection for female intelligence either way in the past. Any male bright enough to come up with cultural/technological changes which are profound enough to change his own culture would have more than a good shot of fathering an above-average number of children. Presumably the somewhat elevated social status would also extend to his children, meaning booted fitness for at least two generations.

    More generally speaking, it’s clear the caloric intake of brain matter is pretty equal whether it’s idling or engaging in high-level cognition. Larger brains need more resources however. The average brain is estimated to need around 260 calories per day to operate. That said, the average Asian brain capacity is only 7.66% greater than the average sub-Saharan African brain (brain size probably shouldn’t be considered on the continental level anyway, as there are big variations within continents). So we’re talking about a difference of around 20 calories a day. Certainly there’s no reason why bigger brains should develop without some selective force pushing them, but outside of an environment where famine happens every few generations, it’s hard to see how caloric needs would select against the large brained – and until the advent of agriculture, death by famine was far more infrequent than death from accidents or warfare.

  • Sandgroper

    #73 – John Hawks ponders why human brains have evolved to become smaller over the past 10,000 years, even adjusting for differences in body size/mass. So might we all.

  • Grey

    “At least in studies of modern society, it’s been shown that intelligent men father more children than the average.”

    Assumptions based on modern society is the point though. I’d always assumed without thinking about it that evolution would be selecting for more brains and other factors had held it back – but maybe for most of the past it wasn’t.

    “but outside of an environment where famine happens every few generations, it’s hard to see how caloric needs would select against the large brained”

    Well it’s not hard to see it as you just pointed it out. However if it is only 20 calories a day then that would be a very weak pressure i guess even if constant and over millenia.

  • jm8

    “Not only has the current version of the British education system eliminated average IQ differences between ethnic groups it has eliminated the differences between individuals as well. They increased everyone’s IQ to the same level!”

    This is not the case. The percent of the general population that get 5 or more A-C grades in the English and Math subjects is usually about 55 percent. Also, gaps between economic classes are much larger than most ethnic gaps.

    The question of dumbing down, its relevance, and other issues are addressed in the above (including in the comments)link as well as here:

    both at a blog which analyses some of the data in several posts.
    The Maths and English subjects do appear to correlate strongly with iq (and g)at about .7-.8, similar to the SAT’s(See Deary.). Other subjects generally show lower correlations. Iq correlations and approximate between test equivalency charts (eg: one’s probability of scoring 5+ a-c in Math/English according to iq) can be found for several test years including recent ones(first two links of #71).


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About Razib Khan

I have degrees in biology and biochemistry, a passion for genetics, history, and philosophy, and shrimp is my favorite food. In relation to nationality I'm a American Northwesterner, in politics I'm a reactionary, and as for religion I have none (I'm an atheist). If you want to know more, see the links at


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