Features, Science / Tech

VOX Goes From “junk” To “no good”: That’s a Bit of Intelligent Progress

I dislike writing responses to articles I feel need correction or clarification. As a journal editor, I do it frequently. In this case, I’m writing a response to a response about responses to a response. By way of introducing this piece, VOX published a critical article about a podcast discussion between Sam Harris and Charles Murray with a disparaging headline about “junk science.” The issue was whether any scientific data support the idea that group differences in average IQ scores might be partially explained by genes (a very minor part of the podcast). The VOX piece thought this possibility was junk. I submitted a response to VOX; they declined to publish it but Quillette did (June 11). VOX then published a second piece where the authors of the original piece responded to a number of online criticisms in considerable technical detail. That second piece had a headline of “still no good reason” to believe genes had anything to do with group differences. In my view, this article was much better than the first and the headline was less objectionable. Nonetheless, I felt it gave VOX readers a one-sided, non-mainstream view of the issue. I also felt VOX was putting a thumb on the scale by endorsing a particular viewpoint with two articles by the same group and no articles that presented other informed views. Reluctantly, I submitted a new response to VOX. Again, they politely declined to publish my response believing it is time to move on to other topics. They have a point. There’s not much more to be said on this hot button issue given current data. In what may be a futile effort to have a last word, I offer my second VOX-rejected piece below:

Let’s talk frankly about genetics and IQ differences

If you finished reading to the end of the new VOX piece on IQ, you may be confused about the role genetics plays in accounting for differences in intelligence. This was an informative article but it’s easy to lose the thread. The key issue discussed is whether the following statement is justified by the state of current scientific research: Average IQ score differences among race-defined groups are partially genetic in origin. Turkheimer, Harden, and Nisbett (respectfully abbreviated THN) assert the statement is not justified by available evidence. The impetus for this article, the second published by VOX on this topic by these authors, is a podcast discussion between Sam Harris and Charles Murray that included an affirmation of the statement. Both positions derive from a widely held formulation among researchers who specialize in intelligence research called the Default Hypothesis: Whatever factors influence intelligence differences among individuals will also influence average differences among groups.

THN do not like this hypothesis although each author acknowledges somewhat different reasons. Like good prosecuting attorneys, they lay out their evidence and their argument seems compelling. However, as observers of courtroom dramas know well, there are other equally reasonable interpretations of the same data and other evidence can be introduced when the defense has a turn. This give and take is common in science but discussions about different interpretations regarding intelligence research often turn on technical details and confuse non-scientists interested in the subject.

Based on my understanding of the research literature, many disagreements about the data result from a loose use of language. The words “intelligence”, “IQ”, and “g-factor” are not equivalent although they typically are used interchangeably. Each has its own relationship to data. Intelligence is a broad word that includes many mental/cognitive abilities, IQ is a summary way to assess or estimate a person’s rank on many of these abilities compared to others, and the g-factor is one component of intelligence that emphasizes reasoning ability common across a wide variety of situations. IQ scores are good estimates of the g-factor but an IQ score also taps other components. When we talk about differences in IQ scores, they may or may not be due to the g-factor alone.

Considerable research shows the g-factor has strong genetic influences and weaker environmental ones. However, there is a paucity of modern DNA evidence about group differences, best defined by DNA-assessed populations rather than race. But that is about to change dramatically as multinational consortia gather DNA and cognitive test data from large samples around the world. These databases coupled with new statistical methods potentially can answer fundamental questions about individual and group differences. That’s why a frank discussion about all this is timely.

The worst that detractors can say about the podcast is that Murray and Harris prematurely endorsed the Default Hypothesis as resolved. Similarly, in my view, the VOX piece prematurely rejects the Default Hypothesis as somewhere between unreasonable and not provable.

In my experience, presentations of research data to non-specialists easily fall into overly simplistic conclusions and charges of cherry-picking evidence. Here are three things to keep in mind as you form your own opinion of what the data mean: 1) intelligence is a function of the brain and no story about the brain is simple, 2) no one study is definitive, 3) it takes many years to do independent replications and sort things out until there is a compelling weight-of-evidence to support some interpretations over others. We all should be careful when advocates for a particular point-of-view claim the moral high ground. The science will sort itself out — it always does. In the meantime we need to encourage more discussions like the Harris/Murray podcast and be resolute in supporting the expression of controversial ideas and informed challenges to them like the THN piece.

Robert Plomin, an expert in behavioral genetics, wrote in 1999, “The most far-reaching implications for science, and perhaps for society, will come from identifying genes responsible for the heritability of g [i.e. the g-factor].” The Chinese government apparently is devoting considerable resources to this endeavor. Meanwhile in the US, the majority of the Congress apparently does not believe evolution is more than a theory. This is an important story in the 21st century.

In my view, the research data show that individual differences in intelligence, especially those related to the g-factor, are strongly influenced by genes. It’s a challenging story about multiple neurobiological cascades initiated by genetic and environmental interactions. How all this works will take years to disentangle; it is a complex but exciting and finite set of puzzles to solve. The data on group differences, however, has not yet established a reliable weight-of-evidence. New data are coming in the next few years with advanced methods of analysis and controversy is sure to follow. Respectful public discussion is essential and scientists have an obligation to provide non-specialists with understandable explanations of highly technical methods and results. Listen carefully to the Harris/Murray podcast and read what THN say. Both are worth your time. Neither is definitive yet but scientific progress is moving inexorably toward a clearer understanding about the origins and nature of intelligence differences. Let’s be open to what we find out.

Filed under: Features, Science / Tech

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Richard Haier is Professor Emeritus, University of California, Irvine, editor-in-chief of Intelligence, a scientific journal, and author of The Neuroscience of Intelligence (Cambridge University Press, 2017) that includes hundreds of recent scientific references to support the arguments made here.

25 Comments

  1. roylofquist says

    Perhaps race is a false correlation. It is fairly well accepted that consanguinity can cause mental disability. Although first cousin marriages result in a very slight risk, well under 1%, if consanguinity is compounded over many generations the result is significant (1.0025 e 50 = 1.13). This chart shows the global prevalence of consanguinity:

    http://www.consang.net/index.php/Global_prevalence

    Note that it correlates closely with racial origins.

    • Santoculto says

      So MENA people must have the lowest scores…

        • Santoculto says

          Based on this logic most exogamic “or” mixed race people must be the brightest.

        • Santoculto says

          Seems soft degrees of consanguinity is not bad at all. There is a icelandic study that seems showed this.

        • Aris says

          “Note that in the consanguinity chart there is no data for Africa. I suspect that because of the tribal nature of African societies their consanguinity rate is comparable to MENA.”

          Just to point out that the issue is with the higher levels of homozygosity that consanguinity leads to. Thus, as is expected homozygosity is inversely correlated with distance from Africa. The further away you are from Africa, the higher the levels of homozygosity. So what you are saying is not correct. And of course the MENA levels of consaguinity (which are due to cultural reasons), are considered around the same as the levels of mid-19th century British populations.

          and

          “Actually Africa has the lowest estimated IQ scores: https://iq-research.info/en/page/average-iq-by-country

          The data on that website are out of date. New work from Jelte Wicherts et al. has shown that the average IQ of sub-Saharan Africans is 82, based on current samples, rather than 70 that the work of Lynn & Vanhanen concluded.
          Therefore, if you wish to push forward the hypothesis that current IQ differences reflect the genetic potential, you can’t reconcile that with the levels of consaguinity.
          This is why I currently think that the hereditarian hypothesis of lower cognitive ability of sub-Saharan Africans is not likely to be true. Unless we show strong selection pressure on significant amount of genes that influence intelligence, there is no reason to be agnostic. The default hypothesis should be consistent with Lewontin’s apportionment of human variation, i.e., that there will be more variation (in intelligence genes) within continental populations, rather than between them.

          Of course there are other data as well. Steven Pinker in one of his books mentions the data gathered by Thomas Sowell, who illustrates that group differences in minority groups were the rule in the 20th century. Minority groups outside the cultural status quo tend to lag behind, and they catch up as time goes on.

          • Chuck says

            “The default hypothesis should be consistent with Lewontin’s apportionment of human variation, i.e., that there will be more variation (in intelligence genes) within continental populations, rather than between them.”

            Yes, I agree. I have called this the “evolutionary default hypothesis”. For the formula, check:

            e.g., DeFries, J. C. (1972). Quantitative aspects of genetics and environment in the determination of behavior.
            &
            e.g., Leinonen, T., McCairns, R. S., O’hara, R. B., & Merilä, J. (2013). QST–FST comparisons: evolutionary and ecological insights from genomic heterogeneity. Nature Reviews Genetics, 14(3), 179-190.

            expected phenotypic difference = between group genetic variance * h^2
            between group genetic variance ~ 2*Fst in low mutation genetic markers e.g., SNPs

            “This is why I currently think that the hereditarian hypothesis of lower cognitive ability of sub-Saharan Africans is not likely to be true. Unless we show strong selection pressure on significant amount of genes that influence intelligence.”

            Do the math. I don’t think you are going to like the results.

            “there is no reason to be agnostic”

            backtracking in 3, 2, 1 …

            Regarding the nonsense about heritability, what sub-field? I have never heard anyone object to e.g., Qst>Fst comparisons on the grounds that partitioning phenotypic variance is meaningless.

          • aris says

            I am glad that we can agree on one part at least.

            However, leaving your armchair inference aside (formal inferences show that the proportion of variance in the trait, that can be attributed to genetic differences between populations is not more than the single locus proportion between those populations), what makes you think I cannot reconcile both of those positions in a coherent thesis?

            What makes you think I am not already aware of your inference before making my claim?

            Your inability to realize that a consistent application of that premise leads to agnosticism about the causality of (part) of the gap at best, and a predisposition towards environmentalism at worst, reminds me once again how the whole “debate” is mostly political and based on intuitions rather than scientific.
            I suppose your smugness to predict my “backtracking” prevailed there, but I digress.

            Thank you for your comment anyways. Peace out.
            (Apologies for the late response)

  2. Santoculto says

    Or maybe too early pregnancy may have some effects that are similar to consanguinity even it’s depend the group, maybe its their biological normal.

    In the end, Africans on general are less “self’ domesticated than Europeans and east Asians. This may explain why they are more prone to score lower in IQ tests/ early brain maturation and to be impulsive/less delayed gratification.

    IQ is just like the tricks trained dogs tend to learn.

  3. Aris says

    “Considerable research shows the g-factor has strong genetic influences and weaker environmental ones.”

    A couple of points about that statement. This is built upon premises about heritability figures, but heritability can be interpreted differently, so there can be genuine disagreements in that respect.

    The whole point is based on the premise that nature (heredity) and nurture (environment) can be separated meaningfully using the heritability index, but that is actually challenged both theoretically and empirically.

    First theoretically by the work of population geneticists, such as Richard Lewontin who eloquently made the case that “nature vs nurture” is a false dichotomy, there is a dynamic relationship between the two.
    In an article in 1976 he writes:
    “if two men lay bricks to build a wall, we may quite fairly measure their contribution by counting the number laid by each; but if one mixes the mortar and the other lays the bricks, it would be absurd to measure their relative quantitative contributions by measuring the volumes of bricks and of mortar. It is obviously even more absurd to say what proportion of a plant’s height is owed to the fertilizer it received and what proportion to the water, or to ascribe so many inches of a man’s height to his genes and so many to his environment.”

    He basically mirrors the comments of the brilliant geneticist Theodosius Dobzhansky, who believed that the correct way to view the genotype-phenotype relationship for an organism, is through the lens of reaction norms.

    There is strong consensus about this view in philosophy of science as well. The philosopher Ned Block has written about this, back in 1995, in his paper titled: “How heritability misleads about race”. A more recent account comes from the philosopher Robert Northcott about the “Causal efficacy and the analysis of variance”.
    Hereditarians usually cite the work of the philosopher of science Neven Sesardic, but his work is far outside the consensus. Worth noting that Sesardic’s work is mostly polemic, questioning the political motives of the philosophers that disagree with him, and his arguments are far from convincing.
    A better work that is more modest and can be used in support of hereditarian arguments comes from the philosopher Christopher Pearson in his work “Is heritability explanatorily useful?”, but this is still outside the consensus.

    Now I want to move to the empirical challenge of the premise which comes from non-human animal research about social behavior. Leading research in the field of sociogenomics shows that the genes in the brain are malleable, switching on and off in response to environmental cues. That doesn’t mean that genetic variation is not important, but that social behavior and interactions alter the expression of the genes in the brain. There is a dynamic relationship between genes and environment.

    In my view, for example, I can fully reconcile the claim that “black-white IQ differences are genetic” with the claim that “the IQ gap will go away in the future”, because I adopt Dobzhansky’s’ framework of reaction norms.

    Considering how hard it is to conduct controlled experiments in humans (see: Turkheimers essay “Spinach and Ice Cream: Why social science is so difficult”), I find it quite implausible that we are the outliers, that our genes do not have that dynamic relationship with the environment, and that the heritability figures are as meaningful as many think they are.

    • Santoculto says

      ”Now I want to move to the empirical challenge of the premise which comes from non-human animal research about social behavior. Leading research in the field of sociogenomics shows that the genes in the brain are malleable, switching on and off in response to environmental cues. That doesn’t mean that genetic variation is not important, but that social behavior and interactions alter the expression of the genes in the brain. There is a dynamic relationship between genes and environment.”

      Critical part where lunatics on ”epigenetic miracles” use ”animal research” to test their post-modernistic theories…

      ”Genes in the brain are malleable”

      how much* endless*

      I will explain to you

      We are all born, more or less, with the same behavioral palette, partially disregarding those with more explicit mental disorders, I said partially …

      We can all be: pleasant, hostile, witty … we can be: sad, happy, angry.

      However some tend to be more one way than another, and of course, that we have our sorround or environment in which we live, and that we interact ” with it ” [read: ESPECIALLY with people]. The main element in our environments are people, beings of the same species.

      Most of the time we look for people who are similar to us in temperament or complementary. It is not uncommon for us to be born into direct families where, contrary to similar or complementary people, we have the opposite. For example, I was born into a family in which I am particularly different from my relatives in temperament, although I have inherited more of my mother a more neurotic temperament. And I have an older brother who has a temper for psychoticism. He is more aloof, unstable mood, very emotionally immature and we constantly get into friction. I internalize criticism, he is more likely to do it [and in a dry way]. If I were in another environment with a person who is not my ‘astral hell’, I would probably be a lot less neurotic. However, in the same environment, we can find people who will react differently. And indeed, in my house, I have another brother who reacts in a completely different way. This is just a miserable example of something that happens in constant cascade around the world, at all times, in homes, or in work environments, at school.

      In the same environment, exposed to the same micro-dynamics, different people react differently. You do not need to prove this in a controlled university study because you can think [I believe] on your own, especially if you do it logically. It should not be difficult to understand this, but when we have the ” religion ” at stake, it complicates.

      Of course, or it seems clear, that the brain is not static. However, it also seems clear that the brain is not like the Mistica, that mutant …

      Ingsocial science is not too complicated, it’s confused by brightly stupid people or stupidly bright people, it’s your choice, sorry, my environment made me do it, =(

      ”I find it quite implausible that we are the outliers, that our genes do not have that dynamic relationship with the environment”

      Strawman…

      Explain more in details what ”dynamic” you’re saying….

      • Aris says

        I think you are misunderstanding my point. I am not claiming that we are “blank slates” in any sense. That would be absurd. I am a biologist after all.

        What I am trying to point out is the limitations of the heritability index, especially when you are trying to move from an observed group to another. For example, Charles Murray seems to think (even though he dances around this) that just because the heritability of IQ is around 60%, that means that it is plausible that around half of the IQ difference between blacks and whites is genetic. I don’t think this follows at all.

        Obviously the genes are the ones that are “malleable” and the ones that are “turned on and off”. So I can reconcile my previous claim with a claim that intelligence is influenced (even strongly) by genes.

        However, I am quite confused. Are you saying that the empirical evidence which shows that many of the genes in the brain (in mice, birds, etc,) is changed due to different environmental cues, is either false or not applicable to humans?

        I think a better counter-argument to this point comes from Richard Haier himself who said in another essay of his that intelligence could very likely have evolved to be stable because of the instability of early human environments. Which makes sense, but still we need more data.

        If you are interested you can look at this perspective essay in Science:
        http://science.sciencemag.org/content/304/5669/397

        You can also read the theoretical analysis from the papers I mentioned in my above comment.

        Take into account that the theoretical limitations of heritability are points that date as back as Ronald Fisher, who by the way was a proponent of eugenics.

        • Santoculto says

          ”I think you are misunderstanding my point. I am not claiming that we are “blank slates” in any sense. That would be absurd. I am a biologist after all.”

          Many biologists believe after all.

          ”What I am trying to point out is the limitations of the heritability index, especially when you are trying to move from an observed group to another. For example, Charles Murray seems to think (even though he dances around this) that just because the heritability of IQ is around 60%, that means that it is plausible that around half of the IQ difference between blacks and whites is genetic. I don’t think this follows at all.”

          I think we would need to separate the amount of heritability, conception, prenatal period and early childhood.

          What is the critical period of ” biological transmission of behavioral characteristics ” *

          This happens equally with everyone else, except with those who present major developmental disorders *

          Either these disorders are already transmitted during conception *

          I always understand the term heritability as a potential of heredity.

          If assortative mating patterns are a constant in human evolutionary history then heritability may vary, for example, when two biologically similar persons marry, heritability increases [especially in racial and phenotypic terms: for example, Caucasians of a European population Is more sub-racially homogeneous + more autistic personality]. When people are more biologically different, the heritability [of a certain trait] decreases.

          ”Obviously the genes are the ones that are “malleable” and the ones that are “turned on and off”. So I can reconcile my previous claim with a claim that intelligence is influenced (even strongly) by genes.”

          I think all traits are strongly influenced by the genes, if not fully influenced. Even if we were as ” blank slaters ”, it would still be because of the nature of our genes, not because of anything else but our genes.

          What is at stake here is how reactive the gene can be in relation to the environment in a positive and negative way.

          ”However, I am quite confused. Are you saying that the empirical evidence which shows that many of the genes in the brain (in mice, birds, etc,) is changed due to different environmental cues, is either false or not applicable to humans?”

          First I do not even know if I should debate this monstrosity with calmness or banality. On the plus side, I do not know what kind of ” cunning experiment ” was employed to have a certain outcome.

          Our behavior is limited dynamically. Of course, gene expression varies, such as weather. If I am irritated today and tomorrow I become calmer, then this should probably be manifesting at the genetic level. But this does not prove that there is no limit to this malleability.

          • Santoculto says

            I do not know, but depending on the size of the animal and the type of animal, yes, because they vary in personality. If none of this has been controlled [psychopathy is ok], a certain type of ‘experiment’ can have devastating effects on its development.

            Such ‘experiments’ are like: let me see if I set fire to my wooden furniture, if that will burn it.

            Small animals have micro-environments and it is not obviously uncommon for them to be considerably adapted to very specific environments. Artificial ”experiments” can stress them at the point to alter part of their genetic expression [vitalicious sequela*].

            But yes, a rat is a not human. Pure instinctive species [ seems most of living beings] can suffer direct impact on environmental turbulences, even because their behavior tend to be considerably more objective, direct.

            One of the characteristics of the human being is being able to adapt to a [relatively] larger number of environments.

            ”I think a better counter-argument to this point comes from Richard Haier himself who said in another essay of his that intelligence could very likely have evolved to be stable because of the instability of early human environments. Which makes sense, but still we need more data.”

            But, seems, this is a feature for any evolutionary trajectory of any species.

            I think that as the basal human being was a ” weak ” hunter, compared to other animals, then: either he needed to find means to compensate his weakness, and intelligence appear to be perfect to reach this need, clearly a ” Lamarckist ” narrative. Or as it almost always seems to happen, natural personality differences have been appearing among primates since earliest human-primate divergences, and they have been mating progressively between themselves until become the first humanoids.

            Progressive personality differentiations [personality =evolutionary strategy] seems a important drive on speciation, without [natural] geographical isolation. A prior motivation to mate closed.

          • Aris says

            My apologies. I thought the article was open-access. Here is a link to the pdf: https://www.life.illinois.edu/robinson/storage/pdfs/NatureNurture.pdf.

            There is a whole literature behind this. You can track the original research findings that the paper cites and maybe read a couple of them. You can then pass your judgement. I imagine that there can be genuine disagreements with the methodology and theoretical framework used, which would make my points not resonate with you.

          • Santoculto says

            ”Many social and behavioral scientists are skeptical
            as well, either because the concept of
            “DNA as destiny” does not jibe with their
            understanding of the dynamic nature of behavior
            or because they consider human behavior
            to be much more complex than that
            of animals studied from a genetic perspective.”

            If human behavior ”is much more complex” [than…] why ”STUDY” other living beings*

            ”By contrast, biologists have long accepted
            that genes, the environment, and interactions
            between them affect behavioral
            variation.”

            Even my grandmother’s, in memorian, may accept this. I think most of ”hereditarians” also accept this.

            But affect in how degree* how vitalicious degree*

            ”Unfortunately” because we live only one time, seems ”we” can’t to test the same individual more than this, to see how diverse s/he may would be capable to react, to behave [act/react].

            It’s or seems dumb to say ”us and environment/them is not a dichotomy”. It’s the same to say ”shadow and light dynamics is not a dichotomy”. Because the being x environment have a dichotomical nature, doesn’t mean it’s never touch or influence one each other. We are, literally speaking, movable/derivative parts of overall environment that encapsulate us. But we have something called self-conscious individuality, even the first living beings have it.

            ”It is now clear that
            DNA is both inherited and environmentally
            responsive.”

            Yes but how*

            ”Behavior is orchestrated by an interplay
            between inherited and environmental influences”

            inherited = instinctive* instinct*

            Humans have larger instincts/larger memory and subsequently behavioral plasticity [namely self-consciousness]. Everything what we really internalized become ”de novo/new instinct”. Humans as well other species, but specially our species, can expand their instinct size or ”collection of easily retrievable behaviors: cognitive and affective”.

            When my older brother is boring [usually] [aka, ”environmental influence*”] i become neurotic. Because this situation has been common in my life i ”learned subconsciously” to become more neurotic, very likely a defensive behavior. BUT, i was born with this trends.

            Different humor = different genetic expression*

            Different people in the same environment [my brother is usually unpleasant with other people on my direct family] react differently.

            If i tan myself on the beach the genetic expression of my skin cells will change temporarily*

            If i tan or take sunlight too much AND i have vulnerability to develop skin cancer, so maybe…

            Two people who smoked during all their lives. The first develop cancer, the second not.

            IT’S CLEAR that it’s ”genetics” or something intrinsic to individual and not to environment in both cases, to protect and to predispose.

            This example can be easily extrapolated.

            We can expand our inherited instincts beyond themselves based on [degree] levels BUT not exactly in type.

            I was born with potential to expand my verbal skills on my mother/first tongue, and i did it, firstly because i was born with it, secondly because i was exposed to ”regular earlier environment” with nothing great or bad in terms of ”environmental stimuli”. Thirdly this reached potential was/is limited.

            Maybe it’s predominantly true that too harsh environments can depressed ”genetical potential” [temporarily*] but ideal environments will not make miracles and people of different populations with different evolutionary and familial history will not become ”the same”/”equal”.

            ” Variation in
            maternal care in rats is inherited; pups that
            receive the minimum care from their mothers
            grow up to return the favor when they
            have their own offspring. Apparently, pups
            experiencing indifferent care show profound
            changes in brain gene activity, including
            decreased expression of the glucocorticoid
            receptor gene. But these inherited
            differences in gene expression and behavior
            occur even in the absence of DNA polymorphisms.
            In the case of the glucocorticoid
            receptor gene of neglected rat pups, it
            is epigenetic modification of the DNA sequence
            through methylation that is involved
            in their altered adult behavior (8).
            Hence, environmental influences on behavior
            can cause epigenetic changes in the
            genome that are inherited.”

            If ”genetic confound” is being correctly analysed firstly, ok

            Tell me

            Play video games increase IQ*

            Maybe some rats are mutants in this facet**

            I invent the term ”metaphormic genes”, more or less in line with ”epigenetics”. We have: dominant, ….. and recessive. MAYBE some ”genes” need more nurture than others to be fully expressed OR are more sensible to environmental turbulences. Some categories of [human] characteristics are more ”epigenetic” than others. Maybe it’s the case for height [that as well a plant, in most cases, because overall human conjunture, need to be environmentally nurtured to grow healthly. But some people inherit ”fixed” genes to height and even in good environment they don’t grow above the average or even below.

            Even it’s true that some people can become violent in certain environments and this mean ”environmental influences” and the way this people INTERPRET it made them violent, many others will not become…

            Even i have a pitbull and he’s a grace, but somethimes he is angry with some person…

            There are some unfortunate cases of aparent regular fathers of family that become crazy by any rational reason and kill their family and themselves.

            Between put in risk: people, beings, nature, everything and try to be tolerant with this kind of unpredictable people i prefer don’t risk nobody.

            Even many black men were ”normal” in their childhood but become violent/criminal and start to commit crimes against innocent people, and the way they interpreted their live-path made them change their conducts, AND we can conclude: genes but big role of environment. I still prefer predictably rational people or at least predictably regular people.

  4. MRB says

    I appreciate the back-and-forth, but I suspect the fraction of people reading any of these articles who will change their opinions is close to zero, and only slightly larger than zero once the aforementioned genetic testing is completed too.

  5. Chris says

    I am reading the comments and had not formed a prior opinion. Do we agree that genes related to/ responsible for IQ may be selected for in some situations?
    And if so, if for hundreds of years one group (could be an isolated island state) starts choosing the smartest kids to procreate and preventing those with the lowest IQ, can we agree that that group will have an average IQ that is higher than another group/island who instead gave procreation rights to only those who could lift heavy items?

    • Yes, but saying so can destroy your career.
      “There is no firm reason to anticipate that the intellectual capacities of peoples geographically separated in their evolution should prove to have evolved identically. Our wanting to reserve equal powers of reason as some universal heritage of humanity will not be enough to make it so.” Dr James Watson

    • Aris says

      Just to clarify. Any trait that has heritability greater than 0, can be selected for. IQ, or to be more precise, G-factor (IQ is considered a proxy of the G-factor) has a heritability greater than 0. Therefore, humans can be selected for the trait of G-factor.

      Of course a better framework, in my view, is the one that involves complex systems that interact with each other, which is why Systems Biology is trending right now. Especially in non-human animal behavior the approach of reaction norms, is the norm.
      See this paper: https://academic.oup.com/cz/article/61/2/251/1792322
      And also this short lecture by YaleCourses: https://youtu.be/nDW0nq6MOiE

      As I stressed above, because of the nature of social science research we can still have genuine disagreements about even the core approaches. For example, the conceptual disagreements about heritability and IQ could be resolved with a series of experiments, if we were talking about non-human animals.

      • Santoculto says

        ”if we were talking about non-human animals.”

        Your mother is not available**

      • Santoculto says

        Less-than-great ”scient–ologists” need use innocent creatures to prove their own stupidity and indisputable evilness.

        Herit-able or inherit-able

        Heritability is the potential for heredity.

        It’s higher in many or some traits seems because has been analysed among identical twins and it’s expected higher shared-heritability in ”quasi-clones”.

        Among a standard human family the inheritance it’s expected/tend to be much more mixed. And among heterozigotic families, for example, with SOME history of disorders + different racial procedences, this inheritance will be even more mixed.

        I concluded that heritability, as a potential to inheritance, don’t varies during life-time, at least its instinctive basis/”directly’ inherited.

        IQ heritability don’t varies from lower or variable in childhood to ”50%” on adulthood.

        Seems conjectural, extrapolated but not proven.

        IQ varies itself, because the stages of brain maturation. Become more fixed or stable when the period of brain development is finished.

        But in the way people have interpreted or conceptualized heritability, seems quite confuse.

        ”The variation of phenotype from genotype”, firstly would be necessary define the genotype itself. If genotype is the primary refference to extrapolate phenotypical variation. For example, everyone in certain family [7 individuals] have the ”same genes/genetic expressions” [at same ”levels”] that predispose to bipolar disorder or overall ”mood disorders’, if this scenario really exist. [[genotype]]

        But ”only” 2 of them express them even they living in the most happier, boring and safe space possible. [[phenotypical variation]]

        This look like the correct application of the heritability concept,

        OR absolutely not…

  6. Santoculto says

    ”Whatever factors influence intelligence differences among individuals will also influence average differences among groups.”

    If groups are basically a aglomeration of individuals. Seems tautological. Individuals are pieces of the totality/groups.

    Whatever fact-ors that influence a group of pieces in given territory will influence them as a group but even different inanimate things have their own internal structures.

    It’s not just ”genes” but ”intrinsicability”.

    Populations are movable environments. Also can be dramatically understood as selective labyrinths. More equal the tracks/ homozygosity, more difficult to go out.

  7. Myron Gaines says

    I agree with the thrust of the article. Decades after the Bell Curve, we’re still in a situation where hereditarianism is strong but not conclusive.

    I regard hereditarianism as settled, but that’s more due to the lack of other possibilities than due to the strength of the evidence.

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