I may have to make “misdreavus” a co-blogger here at some point, considering how I quote him here. But, in defending HBD (Human BioDiversity), he has made a nice basic summary of the reasons why we believe in HBD (that is, overwhelming evidence).
This was all in response to social anthropology scholar A. J. West, who some of you may remember from Cochran’s & Harpending’s. West wrote a post critical of HBD. I’m not going to recite anything from it, because it is a long drawn-out collection of strawman arguments and nonsense. But misdreavus’s response to West was an impressive review of the case for HBD. I am going to annotate it with links to references to his claims (emphasis in original):
1) The scientific basis behind so-called “human biodiversity” (or HBD) is blessedly simple in its obviousness, albeit one that goes shockingly under-acknowledged by most who call themselves authorities in the human sciences. We already have enough evidence that genetic variation in the human species must account, in some non-trivial way, for the variation in phenotypic diversity we see among the major extant human populations living today. By that I refer not only to salient differences such as the height gap between Aka Pygmies and Congolese Bantus, or that fact that west Africans have more prognathous jaws than northern Europeans, but also artifacts of our biochemistry such as Type II diabetes (which usually correlates with obesity) or alcohol metabolism (a large percentage of east Asians have abtabuse built into their genomes — Greenland Inuits don’t). Of course. We get it. There is inter-ethnic (or inter-demic, or inter-population — feel free to choose whatever taxonomic subdivision du jour is fashionable these days among the PC crowd) variation for virtually every single trait for which there exists variation among members of a single ethnic group: no two Irishmen have noses that are exactly the same shape, and neither do any two races, on average. No two Koreans have skin color that is exactly the same hue, and there is a vast gap in skin color between Norwegians and Dinka. No two Russians are of exactly the same height — not even identical twins, and virtually every single Swede is taller than every single Mbuti pygmy. This much is obvious to anyone with an unimpaired frontal lobe.
And we can extend this reasoning not only to the aforementioned physical traits (and much more), but also cognitive skills, however they are defined in every single culture — for virtually every single behavioral trait ever documented among human beings is heritable. [see All Human Behavioral Traits are Heritable] We know that two children who are reared by the same pair of parents can be strikingly different in their behavior and temperament, and that these differences almost always persist long past childhood. It matters not how “personality’ and “temperament” are defined, or that there are not, never have been, and likely never will be any precise definitions of these terms that are useful to psychological science. (Let us avail ourselves of the postmodernist obscurantism, trenchant reality denial, and casual know-nothingness that you decried earlier in a post about social anthropology. It is enough for us to acknowledge that no two humans are alike in behavior, and that the human mind is not a blank slate.) Behavioral differences between any two people, even identical twins, manifest themselves starting from birth, and they only magnify throughout the lifespan. Not surprisingly, it has been demonstrated that babies from different ethnic groups also demonstrate behavioral differences from the cradle. East Asian babies, on average, tend to remain placid and calm when a soft cloth is dropped over their faces — west African and European babies are the polar opposite. See here: http://westhunt.wordpress.com/2013/03/16/dan-freedmans-babies/ [see also this video]
If, indeed, it is the case that human beings vary in behavior, and if it has been proven that much of this variation in behavior may be attributed to hereditary causes, then this alone is sufficient to demonstrate that heredity must explain some of the variation in cognition between any two human populations who vary in their evolutionary history. Well, has this been proven? Of course it has. [see How Much Hard Evidence Do You Need?]. “Heritability”, as the term is implemented in quantitative genetics, refers to the portion of variation in a phenotype within a population that may be attributed to heritable differences, given a certain range of genotypes and phenotypes: H^2 = Var(G)/Var(P). The classical twin study, as much as it is ballyhooed by idiots in the social sciences who are reality-averse, has provided heritability estimates for a wide array of psychological dimensions ranging from IQ and its subscores (visuospatial, verbal, mathematical, etc.), to reaction time, to the “big 5” (e.g. extraversion/intraversion, neuroticism, etc.), to all psychiatric disorders (e.g. autism, schizophrenia), to what brand of cereal you prefer in the morning, and much more. In virtually all cases, these heritability estimates are higher than zero — often substantially higher than zero. They are not only consistent with studies of identical twins reared apart, but also longitudinal adoption studies: studies with sample sizes ranging in the multiple thousands have demonstrated consistently that adopted children, even when adopted during early infancy, resemble their biological parents to a vastly higher degree than they resemble the adults who actually raised them (i.e. “adoptive” parents). [See Taming the “Tiger Mom” and Tackling the Parenting Myth]
And one of the most common, and in fact the overarching application of heritability estimates is evolution. Heritability estimates tell you precisely how much a trait will change in a population, over time, as a response to selection. In other words, if the smallest 25% of all cattle in a herd failed to reproduce every generation, how much would you expect that trait to increase over time? Given even modest selection on any trait from height, to violence, to “visuospatial IQ”, to extroversion, and much more — just about how much heritable variation would you expect see between the disparate human populations on Earth since the time we migrated out of east Africa?
The answer is obvious. if you have read The 10,000 Year Explosion by Cochran and Harpending (which I’m not sure you have), the authors provide ample evidence that substantial heritable change is possible in the relative blink of an eye — hundreds or thousands of years, not just tens of thousands. (Evolutionarily speaking, of course.) It is a trivial matter to ensure that a population, twenty generations from now, will be on average as bright as the brightest 2% within that population today [see The breeder’s equation | West Hunter]. Today’s Scandinavians are not yesterday’s Vikings. Han Chinese in Sichuan Province today are not genetically exchangeable with Chinese during the reign of the first Qin Emperor. Swedes are not Norwegians, Egyptian Copts are not Muslims, and Hejazi Arabs are not Najdi Arabs. I could belabor this point ad nauseam, but I believe I have made my point sufficiently clear.
Of course, this is not to say that all of the variation in behavior you see among human beings is hereditary in origin. Nobody ever claimed that — a heritability estimate below 1.0 proves some source of variation that is exogenous to the germ plasm, or perhaps a statistical artifact that is generated in the process of (imperfectly) measuring the trait in question.
Now, on to some specific points you made in your post:
3) You also misrepresent some of the basic claims of some of the bloggers in the HBD sphere. HBD-chick, for one, who does a lot of blogging about consanguineous marriages and its implications for human evolution. You claim:
That account also makes bizarre claims, like the idea that altruism is greater in societies that have complex marriage systems and that ‘marry out’ of the family unit – because, apparently, when you marry out of your circle for generation after generation, everyone you meet is almost guaranteed to be your relative and therefore worthier of compassion!
No. The point is that human populations vary considerably, throughout the ages, in the degree and prevalence of consanguineous marriages, and that basic arithmetic would show you that this will increase the relatedness of two members within an extended family beyond what may be expected from random mating. The Gulf Arabs have been marrying their cousins for centuries, and this practice possibly dates earlier than the prophet Muhammad — Norwegians and Danes haven’t. This means that Saudis, on average, are much more inbred than your typical northern European, and that this difference can be measured through segments of DNA that are “IBD” (identical by descent) — Arabs share a lot more of these than ethnic groups where cousin marriage is taboo.
The coefficients of relatedness work somewhat like this: normally, your brother shares half of your DNA that is identical by descent, as do your biological parents. Your nieces and nephews share 1/4. Your cousins share 1/8. So on, and so forth. Hamilton’s laws demonstrate altruism (e.g. reducing your own fitness, on the behalf of someone other than yourself) can boost an organism’s fitness, on average, if the recipient of the altruism increases its fitness in a way that is commensurate with the relatedness of the altruist and the recipient. In other words, rB > c.
Imagine that by sacrificing your life to save your brother who is drowning, you thereby ensure that your brother would have three additional children that he would not have otherwise had, had he been permitted to sink (and drown). On average, this would ensure a net benefit of fitness for yourself, despite the fact that you have totally abandoned the carrier of your genes (your body) by sacrificing yourself on behalf of your brother. Why? Because 3 multipled by 1/2 (the fraction of genes that your brother, on average, shares in common with you) is greater than 1. You will have increased your contribution to the gene pool. And any alleles that promote such an altruistic behavior on behalf of a person, for his blood relatives, should increase in frequency through selection [see inclusive inclusive fitness | hbd* chick]. This is especially the case for populations that have been inbreeding throughout the ages — because brothers, in this circumstance, are more related to each other than ordinary brothers. [See technical stuff | hbd* chick]
The idea is that this sort of consanguinity would increase the fitness rewards for altruism on behalf of blood relatives to an unusually high degree that is absent among populations that have been out-breeding. In other words, it increases the odds of nepotism, clannishness, and feuding between clans, among other anti-social behaviors that make a civil society very difficult, among other destructive consequences. (Without peeking, who is more likely to help his brother cheat on a standardized test to qualify for a job — the average Najdi Arab, or the average Finn?)
For societies that have been deliberately outbreeding, the exact opposite scenario occurs — distant relatives, whether you realize it consciously or not, are more related to you than they would be in a society with perfectly random mating, and hence you see higher levels of the low-degree altruism that makes the sort of society you see in Woebegon Lake or Sweden possible. The idea is that Swedes are much more willing to sacrifice their fitness in a modest way on behalf of complete strangers who are members of their ethnic group, e.g. by paying higher taxes, and that this tendency has been selected for since the introduction of Christianity during the medieval era, which forbade consanguineous marriages throughout much of western Europe [see setting the stage? | hbd* chick]. Like I said earlier. You only need hundreds of years to see a noticeable change.
If you remain skeptical of this theory, all is fine, but let me tell you something — it does a decent job explaining why the Swedish welfare state works perfectly fine for Scandinavians, but results in utter dysfunction for Somali refugees. It explains why democracy persistently fails in certain parts of the world, despite billions of dollars spent on aid, foreign advisers, and the best advice of seasoned policymakers — some people don’t give a damn about people outside their extended family, and you can’t change that. It explains why there is a west-east cline in Europe for corruption, social trust, and civic mindedness, inasmuch as they can be measured by political scientists — Ukrainians are much more corrupt than the Norwegians, and they’ve been this way for a long time [see big summary post on the hajnal line | hbd* chick]. It does NOT say that all human behavior is [completely] genetically mediated, or that altruism is automatically greater in societies were people have been marrying unrelated persons. Which is why one or two generations of marrying more distant relatives – or marrying outside the group entirely – won’t produce a substantial change in a people’s behavioral traits. Long-term selective pressures are necessary [see this comment of mine].
Being invaded doesn’t explain why you suspect that your neighbor might rob you if he thought he could get away with it (and of course, your suspicions are valid). It doesn’t explain why, if a friend of yours ever lands any sort of government job, he instantly uses it as a mechanism to rip off other people, and to instantly hire dozens of his unqualified relatives and near-relatives. It doesn’t explain why you can’t get anything done in your neighborhood without paying a thousand bribes, from obtaining a drivers’ license to calling the police in the event of a home intrusion.
Poverty doesn’t explain this well, either. In fact, you might expect the direction of causality to be in the other direction. Hard to get an advanced economy going when people are constantly at each others’ throats, is it? But I digress.
Both Japan and Germany had relatively low rates of these anti-social behaviors when they were being bombed to the Stone Age by the allies. Compare the coordination of Japanese civilians during the war effort to the bumbling of south Italians. (And thank goodness that at least one group of fascists was incompetent.) These behaviors can be fixed through social institutions, but they don’t work all the way — and you have to get them running in the first place, which can be difficult if people in a society simply do not trust each other at all.
You know something is strange when the descendants of Scandinavian immigrants in America are practicing a variant of Jante Law multiple generations after the first stock of founding immigrants — long after they have forgotten how to speak Swedish or Danish or whatever. It might even make you wonder sometime. Why haven’t the corrupt institutions of America polluted them yet? [See Maps of the American Nations and Rural White Liberals – a Key to Understanding the Political Divide]
Why are members of the Chinese disapora from Malaysia to Peru considered a model minority, no matter what the local circumstances? There’s a wide variation in social circumstances between Japan, Malaysia, Canada, France, Indonesia, and the rest — yet in any case, the Chinese tend to behave more similarly to each other than they do to the local people. Their IQ scores are dead similar, as is their record of academic achievement. (In Malaysia they were imported as poor tin miners and laborers — and yet the Malays need race quotas to restrict their entry into universities.)
You’d think you’d find one place on Earth where a Chinatown looks closer to Haiti than it does to Shenzhen, but you don’t. Culture matters, but invoking it to explain all the commonness you see around you simply defies the imagination.
You might think it makes sense, but I don’t.
You can blame just about X on any Y as long as you find an association between the two variables. But here is what I consider most troublesome about “culture only” explanations. They violate Occam’s Razor in just about every way imaginable.
For instance, how is white supremacy responsible for both higher IQs among Ashkenazi Jews AND lower IQs among African Americans?
How are aerial bombings to blame for the high trust and cooperation among Japanese during WWII, yet be simultaneously responsible for lower social trust in eastern Europe or elsewhere?
Why do economists blame natural resources for the social dysfunction and internecine warfare in the Congo, yet also attribute natural resources to the success of western settler nations? Why do Gulf Arabs and Equitoreal Guineans behave so currently when they land upon oil? The former have actually built a society of sorts, while the latter nation has children staving in the streets despite a per capita GDP in excess of $36,000. Why?
Why is a culture of rabbinical scholarship to blame for higher rates of achievement among Ashkenazi Jews, despite the fact that Mizrahi Jews have a parallel culture and yet much lower IQ scores?
Why do different populations react so differently to “white supremacism, racism, and poverty”? Why do some people respond to extreme material deprivation with high rates of violent crime, and others with low crime? How on Earth does poverty boost the athletic abilities of African Americans (while depressing their academic abilities), if both are largely socially determined, which is a standard opinion among sociologists? How does one go up while the other goes down? How on earth can anyone blame high rates of sexual assault on outsider prejudice? [See Richard Lynn’s The Global Bell Curve: Race, IQ, and Inequality Worldwide, Welcome Readers from Portugal!, and “Racial Reality” Provides My 150th Post]
If a single social variable has very different impacts on two different kinds of people, perhaps it is time to explore alternative explanations.
Various other commenters have left responses to West, including me, Greg Cochran, and Henry Harpending. I’m convinced that A. J. West is only able to selectively acknowledge facts. He is very much like a creationist in that regard. Normally, I don’t bother make commentary about the personal attributes of people I debate with, but West’s seeming highly limited and selective regard for facts demands some explanation. His post was quite useful in that it led HBD’ers to review the basics of why we think the notions that fall under the category of “human biodiversity” are correct, much as creationists do for evolution itself. But then, I’m not the first person to draw parallels between HBD-deniers and creationists (see Will Saletan’s Liberal Creationism).
I do want to make a statement on one of the points that misdreavus brought up, a point of much confusion within the HBD world and without. As I have tired to explain in my earlier post, Environmental Hereditarianism, the behavioral and physical traits of people are environmentally context-dependent. The broad environmental context regulates the expression of the genes. There is not a dichotomy between genes and “environment”. Nor could there be one – we are always “with” both. The broad environment includes geography, climate, technology, and prevailing social landscape (otherwise known as “culture”). When the social-technological-geographic landscape changes, you can have broad behavioral change all without genetic change. This explains secular changes that occur too quickly to be a result of evolution, such as the sexual revolution, the modern rise in irreligiosity, the increase in the obesity rate, etc.
(I know that this will still not sink in with some people, but I repeat it anyway.)
A note about “culture” though – the “social landscape”, or even changes in such, don’t exist in a vacuum divorced from genes. As HBD Chick so often asks, where does culture come from? Culture is itself an expression of the genes. Yes, behavior – and for that matter selective pressures – are affected by culture. Which in turn is affected by the genes. Which affects the culture, and so on. This is the essence of gene-culture co-evolution. Even rapid “cultural” change, such as the much bemoaned (by social conservatives) sexual revolution has a genetic influence. Rapid change can result when an idea receives widespread appeal among the people. Both components of this – the origin of the idea itself (a reflection of the heritable temperament of its progenitors) – and its reception among the masses (a reflection of the heritable temperament of adherents) are influenced by genes. In a way then, social revolutions can reflect pent-up genetic “potential” in a population, which may express itself when enough people accept that the idea is “OK” and hence can successfully overturn the established order. This is the essence of HBD Chick’s ideas, and Staffan’s remark on needing to “account” for the “history of communism” when looking at the current state of Eastern European societies (“We can’t adjust for their entire history”). The sexual revolution wasn’t the only revolution of consequence in relatively recent history. The American Revolution itself, the Protestant Reformation, the abolition of slavery in the U.S., the rise of communism in Russia, etc are as well. Historical revolutions are in essence, in many respects, a “changing of the genetic guard”, where the genetic dam “bursts” so to speak. More loosely attached individuals may convert if the idea attains a critical mass (see how much longer? | hbd* chick).
To be clear: this is not to say that “genetic potential” is the only factor. As mentioned, other realities, such as technology and the geographic/climatic landscape affect the viability of new ideas/behaviors, and facilitate or quench their dispersal. However, we do see the role of bursting genetic potential when new groups fission from earlier ones, such as the Quakers, the Puritans, or the Mormons (who are descended from Puritans). And this leads to my observation (so lamented by A. J. West):
But, as I and others have so tirelessly tried to show, the innate differences between people, between individuals, between the sexes, and between groups, is of paramount significance to explaining the world. Indeed, how could it be any other way? This is like trying to explain chemistry without knowing the properties of molecules, atoms, electrons, protons, etc. Taking heredity and its effects on people is simply science, as is human biodiversity in general. How foolish and intellectually stifling is it for “educated” people to act otherwise.