Debunking Denialism

Defending science against the forces of irrationality.

Mailbag: A Concern Troll (?) Tries to Talk About Race and IQ

A reader sent me an email about some arguments put forward by race realists, told me he did not know a good way to refute them and asked me for my take on it. I am not convinced he is a concern troll, but some of the language he used and the fact that the quotes of his opponents cannot be found on the Internet makes me suspicious. However, because it is so hard to tell, I will try to be charitable. The person asked not to have his name posted, so I will just refer to him as “he” or “the reader” below.

Hey there. I found your blog a month or two ago when I started researching the topic of racial IQ differences. Lately, I’ve been debating some people over the internet about this subject using some of the information that you and other egalitarians have provided. As expected, the folks who I was talking with didn’t like what they heard and responded with ad hominem attacks, but there was one point someone brought up that I simply couldn’t respond to.

For me, phrases that stand out here are “racial IQ differences”, “you and other egalitarians” and “one point someone brought up that I simply couldn’t respond to”. The first phrase is suspicious because it associates race with IQ difference, when most individuals who reject race realism thinks that most observed differences are due to other factors besides race. Furthermore, “egalitarian” is a word that reminds a lot about “Darwinism”. It has its uses, but most of the time, it is a concept that those opposing it use to try and make the science-based position appear as if it was an ideology. Finally, The last phrase reeks of concern trolling.

This is not an iron-clad case and we should welcome actual concerns. Also, it is important to respond to the point brought up no matter if the person is a concern troll or a person who has a legitimate question.

The point he “simply could not respond to”

The argument he had trouble with was:

Because it is late and I’m very tired, I’ll just copy and paste what they said: “So you’re going with the “Society discriminates against blacks based on skin color even when they’re raised in white, middle-class families” argument? How do you explain the intermediate IQ scores of mixed-race individuals? They’re not just intermediate, they’re proportionate to racial makeup. Say that an IQ of 85 is 0 on our scale, and an IQ of 100 is 15. The black mean is 85, so 0 on our scale. The white mean is 100, or 15 on our scale. The mean for individuals who are half black and half white is about 7.5 on our scale. For individuals who are one quarter black and three quarters white, it’s about 12 on our scale, or approximately 3/4 of the way from the black mean to the white mean. How do you explain the precision of this relationship? Do you put forth that society discriminates against mixed-race individuals based on their skin color with this level of precision? Don’t you see that that’s preposterous?”

Blending inheritance versus meiosis

A very common belief about race realists is blending inheritance. It is a position that existed before the advent of genetics and asserts that the genetic contribution from parents mixes randomly and the offspring always has some intermediate phenotype. The problem is that this would mean that the genetic variation would decrease substantially in just a few generations (leading to the absurd belief that the genetic structure of one ethnic group could be “diluted” by producing offspring with someone of another ethnic group), but we know today this is not the case.

Instead, this perspective has been replaced by meiosis. Concretely, this means that a child to one parent who is “white” and one who is “black” does not need to have precisely the intermediate IQ.

“1/4 black” is a claim about genealogy, not genetics

The argument uses terms like “white”, “black”, “half-black, half-white” and “one quarter black and three quarters white”. I do no really find these meaningful from a scientific standpoint, but will use them to make a point (keeping them in scare quotes).

The argument uses phrases such as “one quarter black and three quarters white” as if “black” and “white” were alcoholic beverages that you could mix. This has nothing to do with genetics, but about genealogy. Being “one quarter black and three quarters white” means that you have one grandparent that has been categories by society as “black” and three grandparents that have been classified as “white”. But this does not mean that your genetic constitutions are “one quarter black”. Why is this?

Let’s use a cake analogy. Imagine that you have one chocolate cake and one vanilla ice cream cake. Now, take half of the chocolate cake and half of the vanilla ice cream cake and put them together. You now get a cake that is half chocolate, half vanilla ice cream. This represents having a European-American mother and an African-American father. During the production of gametes, only half of the genome will be transmitted (so the offspring will have just one genome, instead of two). So lets cut our new cake in half. How do we make the cut? We could make it across, making so that the new half of the mixed cake is 1/4 chocolate and 1/4 vanilla. But we quickly realize that we can make the cut anyway we want as long as it represents 50% of the mixed cake. So, for instance, we could cut it just between and have one half be 2/3 chocolate and 1/3 vanilla. This is how the situation works genetically.

While you do have 50% of your genes from mom and 50% from dad, it is not guaranteed that those 50% from dad contains 25% from his dad and 25% from his mom. The distribution of alleles from grandparents and further back is subject to stochastic variation. This is obvious, since if we go back far enough we would have gotten less than a nucleotide per great-great-great…-great grand parent.

In other words, there is no reason to suppose that the person who is “one quarter black and three quarters white” would have half the amount of “beneficial IQ alleles” (whatever those are) compared with someone who is “half black, half white”. Stochastic variations mucks it up.

In other words, the supposed discovery that people who are “one quarter black and three quarters white” have an intermediate IQ between “blacks” and people who are “half black, half white” does not make any sense even assuming race realism.

By the way, the claim that people who are “one quarter black and three quarters white” have a different IQ than “blacks” is wrong. An impressive adoption study by Elsie G. Moore (Moore, 1986) done in the 1980s showed that there was no difference in IQ between “black children” and “mixed children” being adopted by middle-class “white” families. So even the basis of the argument is flawed.

Conclusion

Another race realist assertion bites the dust.

Inheritance does not blend. Proportion of genes from grandparents and up are subject to stochastic variation, so “one quarter black and three quarters white” is a genealogical term, not a genetics term. The claim that “black” and “mixed” have different IQ is wrong.

References

Moore, Elsie G. (1986). Family socialization and the IQ test performance of traditionally and transracially adopted Black children. Developmental Psychology, Vol 22(3), 317-326. doi: 10.1037/0012-1649.22.3.317

Nisbett, R. E. (2007). All Brains Are the Same Color. New York Times. Accessed: 2012-11-24

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10 responses to “Mailbag: A Concern Troll (?) Tries to Talk About Race and IQ

  1. Emil Karlsson November 26, 2012 at 18:45

    The person that sent me the above email sent me the following follow-up after reading my post. I am posting this for full disclosure.

    Hello.

    Thank you for responding to my email. Upon taking a second look at my message to you, I realize I could have phrased things a little differently so that it sounded more sincere. However, I assure you that my intention was not to troll, but to find the answer to a legitimate question. I want that to be made perfectly clear, and I apologize for coming off the wrong way. I should also mention that the reason you couldn’t find the person’s argument is probably that it was deleted along with the rest of the thread. (Threads on the board I was on are usually deleted from the server quickly after people stop responding to them so that lack of space doesn’t become a burden.) Also, thank you for omitting my name. I really don’t want people to suspect that my intention was to troll, especially since privacy is obviously pretty important to me.

    Your explanation on genealogy vs. genetics is very sound and I’m surprised I confused the two concepts given what I’ve learned on the subject (although I’m still trying to understand it), and the Moore study you referenced, indeed, shuts down this person’s claim quite thoroughly. I’m glad you took the time to respond, and I will use you for reference if someone makes the claim again.

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  3. James October 25, 2013 at 00:24

    The argument uses phrases such as “one quarter black and three quarters white” as if “black” and “white” were alcoholic beverages that you could mix. This has nothing to do with genetics, but about genealogy. Being “one quarter black and three quarters white” means that you have one grandparent that has been categories by society as “black” and three grandparents that have been classified as “white”. But this does not mean that your genetic constitutions are “one quarter black”. Why is this?

    Let’s use a cake analogy. Imagine that you have one chocolate cake and one vanilla ice cream cake. Now, take half of the chocolate cake and half of the vanilla ice cream cake and put them together. You now get a cake that is half chocolate, half vanilla ice cream. This represents having a European-American mother and an African-American father. During the production of gametes, only half of the genome will be transmitted (so the offspring will have just one genome, instead of two). So lets cut our new cake in half. How do we make the cut? We could make it across, making so that the new half of the mixed cake is 1/4 chocolate and 1/4 vanilla. But we quickly realize that we can make the cut anyway we want as long as it represents 50% of the mixed cake. So, for instance, we could cut it just between and have one half be 2/3 chocolate and 1/3 vanilla. This is how the situation works genetically.

    The cake analogy presents a very inaccurate view of how genetics works. After all, if we could make the cut anywhere, why couldn’t we cut most of the Black half off? A better analogy would be to mix equal amounts of chocolate and vanilla batter together and then bake the batter into cake, then cut the cake in half. With this analogy, it is very unlikely that two thirds of the Chocolate will randomly appear on one side.

    Think of it this way: A quarter represents each gene, heads is White, tails is Black. Flipping the coin represents deciding whether or not the White or Black gene will be passed on. If you flip a hundred thousand quarters, what is the probability that two third of those quarters will land on Tails?

  4. Emil Karlsson October 25, 2013 at 18:02

    The cake analogy presents a very inaccurate view of how genetics works.

    It is a simplification for the lay public to make a complex topic a little bit easier to understand.

    After all, if we could make the cut anywhere, why couldn’t we cut most of the Black half off?

    You can, but this is extremely rare. The probability that, say, all of the “white” parental copies would be taken is (1/2)^23, which is roughly 1 in 8.4 million under an independence.assumption. I fail to see the relevance of your reply.

    A better analogy would be to mix equal amounts of chocolate and vanilla batter together and then bake the batter into cake, then cut the cake in half. With this analogy, it is very unlikely that two thirds of the Chocolate will randomly appear on one side.

    This is a horrible analogy as it assumes blending inheritance.

    Think of it this way: A quarter represents each gene, heads is White, tails is Black. Flipping the coin represents deciding whether or not the White or Black gene will be passed on. If you flip a hundred thousand quarters, what is the probability that two third of those quarters will land on Tails?

    That is not how reduction division works: it is not for every pair of genes, but for every pair of chromosomes. Second, even if it was per gene, humans do not have 100k genes, but more like ~21k.

    For the mathematical answer to the real question, see above.

    • James October 27, 2013 at 01:33

      You can, but this is extremely rare. The probability that, say, all of the “white” parental copies would be taken is (1/2)^23, which is roughly 1 in 8.4 million under an independence.assumption. I fail to see the relevance of your reply.

      That’s my point. And the probability of 2/3 of the copies being White is lower than the probability of being 1/2 White. The number in the exponent should be greater than 23.

      This is a horrible analogy as it assumes blending inheritance.

      Not if you look at the cake at the microscopic level. How much of the Chocolate “flavor” ends up on one side versus another?

      That is not how reduction division works: it is not for every pair of genes, but for every pair of chromosomes.

      Ever heard of crossing over?

  5. Emil Karlsson October 27, 2013 at 12:45

    The number in the exponent is 23 because of reduction division. Also, crossing over does not occur for each single gene.

  6. Barzo October 27, 2013 at 22:11

    Interesting reading…. Not sure where I stand on this yet…,.where would you stand on 100m sprinting?

    Given the vast majority of blacks in the US are of West African origin and blacks completely dominate sprinting in the US, is it fair to say that on average blacks in the US have a genetic advantage for sprinting?

  7. Emil Karlsson October 27, 2013 at 23:20

    Given the vast majority of blacks in the US are of West African origin and blacks completely dominate sprinting in the US, is it fair to say that on average blacks in the US have a genetic advantage for sprinting?

    Not even close to accurate!

    African Americans who win sprinting are not representative of African Americans as a whole, even if there was a clear difference on the population difference this would not entail a substantial genetic cause etc.

    Here is a good BBC News article that might make it clearer:

    Every winner of the 100m since the inaugural event in 1983 has been black, as has every finalist from the last 10 championships with the solitary exception of Matic Osovnikar of Slovenia, who finished seventh in 2007.

    Assuming that this success is driven by genes rather than environment, there is a rather obvious inference to make – black people are naturally better sprinters than white people. Indeed, it is an inference that seems obligatory, barring considerations of political correctness.

    Logically flawed

    But here’s the thing. This inference is not merely false – it is logically flawed. And it has big implications not merely for athletics, but for the entire issue of race relations in the 21st Century.

    To see how, let us examine success not in the sprints but in distance running, for this is also dominated by black athletes. Kenya has won an astonishing 63 medals at the Olympic Games in races of 800m and above, 21 of them gold, since 1968. Little wonder that one commentator once described distance running as “a Kenyan monopoly”.

    But it turns out that it is not Kenya as a whole that usually wins these medals, but individuals from a tiny region in the Rift Valley called Nandi. As one writer put it: “Most of Kenya’s runners call Nandi home.”

    Seen in this context, the notion that black people are naturally superior distance runners seems bizarre. Far from being a “black” phenomenon, or even a Kenyan phenomenon, distance running is actually a Nandi phenomenon. Or, to put it another way, “black” distance running success is focused on the tiniest of pinpricks on the map of Africa, with the vast majority of the continent underrepresented.

    The same analysis applies to the sprints, where success is focused on Jamaicans and African-Americans. Africa, as a continent, has almost no success at all. Not even West Africans win much.

    The combined forces of Mauritania, Guinea-Bissau, Sierra Leone, the Republic of Guinea, Liberia, Ivory Coast, Togo, Niger, Benin, Mali, the Gambia, Equatorial Guinea, Ghana, Gabon, Senegal, Congo and Angola have not won a single sprinting medal at the Olympics or World Championships.

    The fallacy, then, is simple. Just because some black people are good at something does not imply that black people in general will be good at it.

    Labelled box

    Imagine a similar argument using the Central African Bambuti, a black tribe more commonly known as Pygmies. With an average height of 4ft we could assert that the Bambuti are naturally better at walking under low doors. Would it be legitimate to extrapolate that black people in general have a natural advantage at walking under low doors?

    I recommend reading the entire article, it is a great read.

    At any rate, your gambit is painfully obvious: you were trying to get me to agree with your assertion, and then you would make the rhetorical comeback that if “blacks” can have a “genetic advantage” over “whites” in e. g. sprinting, then “whites” can have an allegedly “genetic advantage” over “blacks” in some other area (presumably you would bring up intelligence) and denying this would supposedly be a symptom of an alleged suffocating “political correctness” gone mad.

    I call your bluff.

    • Barzo October 28, 2013 at 03:32

      yeah you’re right, I deliberately chose something ‘safe’, if you had agreed I would have then ‘escalated’…. However, I don’t really have an agenda here, I generally believe most differences can be attributed to culture, however when I came across sites which claim race doesn’t exist at all, for me currently that’s hard to understand or agree with….

      I’ve already read this BBC article, it makes sense. However, in this case we’re not talking about ‘blacks’, we’re talking about ‘blacks from Western Africa’.

      Wouldn’t it be correct to say that ‘Blacks of Western African origin’ on average have a genetic advantage when it comes to 100m?

      If not, how would you explain why all the winners of the 100m are ‘blacks of west African origin’ – I guess this is my main question

      The BBC article doesn’t answer the question: why people from Western Africa so good at sprinting and why are people from Nandi so good at distance running? With the Nandi example I can imagine cultural reasons playing an important role, but in the Western African example I currently believe a genetic answer must be the answer.

      These are genuine questions, I’m not trying to catch anyone out, yes I do currently have a pre-existing belief in the existence of race but I’m open to and genuinely interested in your viewpoint. . .

    • Emil Karlsson October 28, 2013 at 19:01

      yeah you’re right, I deliberately chose something ‘safe’, if you had agreed I would have then ‘escalated’….

      As I suspected. Don’t worry, I have debated the issues I cover on this blog for a very long time, so I can see such gambits coming a mile away. Call it an occupational injury.

      I generally believe most differences can be attributed to culture, however when I came across sites which claim race doesn’t exist at all, for me currently that’s hard to understand or agree with…

      I think it boils down to how people interpret the phrase “race doesn’t exist”. Many race realists think it means is something like “there are no genetic differences between populations” or “everyone is genetically identical” leading them to conclude that there must be some kind of “suffocating political correctness gone mad” or similar.

      In reality, when used by scientific skeptics like myself and biologists in general, the phrase means something more complex and elaborate, such as: “There are genetic differences between populations, but this pattern of human genetic diversity does not correspond to traditional racial categories (i.e. the way most race realists view human genetic diversity) and therefore, using the term ‘race’ is misleading and inaccurate.” I could go into additional detail about this but I have already covered it in other posts (and especially the length discussions in the comment sections of those posts).

      Wouldn’t it be correct to say that ‘Blacks of Western African origin’ on average have a genetic advantage when it comes to 100m?

      Probably not, because there is an issue of non-representativeness (both when comparing West Africans and “blacks” overall and when comparing West African sprinters and West Africans in general). Compare with the disproportionate number of top chess grandmasters from countries in the former Soviet Union: does this mean that people living in Russian and related countries have a genetic advantage when it comes to playing good chess? Or is it, perhaps, that one can exploit the genetic potential that exists in virtually all populations by encouragement and training?

      why people from Western Africa so good at sprinting and why are people from Nandi so good at distance running? With the Nandi example I can imagine cultural reasons playing an important role, but in the Western African example I currently believe a genetic answer must be the answer.

      Most genes that have been under differential positive selection in African populations are related to immune system variation, malaria resistance, skin color, hair texture, some blood antigens, lactose tolerance and so on. The three process that have driven recent human positive selection has been disease, food source and climate. This differential positive selection accounts for about 1% of differences between human populations (the remaining difference is due to genetic drift, founder effects and background selection).

      You can read more about this in the following Nature Reviews Genetics paper: Natural selection has driven population differentiation in modern humans. None of the genes under differential positive selection were related to athletic performance or brain development, which makes sense since being smart and athletic is evolutionary beneficial in pretty much all environments.

      This is a good example of what I wrote about earlier: the genetic differences and reasons for recent positive selection in different human groups are hardly ever what race realists think they are. This is sometimes a bit infuriating, as there are so much interesting things to learn about human genetic diversity. However, the topic keeps getting dumbed down by some race realists on Internet forums trying fit a broad and complex research field into their narrow box.

      I won’t bore you with the calculations, but since the between-population variation in humans is around 11% and even if we assume a heritability of sprinting ability of 0.5, that would only translate into 5.5% of the variation in sprint talent being accounted for by genetic variation. If we use more realistic values for heritability, it is even lower. This means that “a genetic answer must be the answer” does not accurately reflect

      Essentially, most of the nation differences in sport results probably boils down to demography and wealth. Large and rich countries tend to do well across the board (U. S., Russian, China, Great Brittan and Germany being a couple clear examples and these are the top five medal earners for 2012 London Olympics), whereas small and poor nations are only able to do well in a couple of sports. Which sports that are depends on many factors, such as culture and geography (e. g. Kenyan endurance runners often train at high altitudes because they have a lot of mountains available, Jamaican has a strong national pride for sprinting etc.).

      These factors enhance the underlying genetic potential for athletic ability that exists in all populations across the world. Obviously I do not know the reason for why each country focuses on the sports they do or in what way the engineer the environment to produce excellence, but I think the arguments in this comment is enough to undermine your general conclusion.

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