Razib, 
 
You're probably familiar with regression to the mean.  
 
The mean for the offspring is close to the midpoint for the parents (measured in standard deviations), but slightly closer to the population mean. Nevertheless, if dad is +2 SD and mom is +4 SD, the kids will be distributed around a mean of somewhat less than +3 SD. Starting with an elevated mean, it's much easier to get a prodigy. Of course, you can end up with kids who are far better or worse than the parent, and the distribution is only evident if you have a huge number of kids :-) 
 
This is well-studied for height, but perhaps less so for IQ. In the case of height I seem to recall that the regression factor is something like .8 (so +3 SD would become +2.4 SD, or something like that). 
 
Note, this doesn't address the non-Gaussian aspect of your comment -- the tails aren't exactly Gaussian, so other factors intrude when you are interested in very rare cases.

Razib, 
 
Thanks for clarifying. BTW, I shoud have written "E. Asian" instead of "Asian" in my comment :-) 
 
It does seem to me that a lot of Americans of E. Asian descent (people I know) have no trouble drinking milk in reasonable quantities -- in fact I only know a few people who have severe intolerance, and some of those are caucasians. It might be the gut flora doing the trick, though!

I believe that although lactose tolerance has a genetic component, diet also has an influence. I suspect that kids (e.g., Asian kids) who continue to drink milk while growing up are more likely to retain their lactose tolerance than those that don't. Milk, cheese, yogurt, etc. are largely absent from the traditional Asian diet after infancy, and I suspect this contributes a lot to adult lactose intolerance. I think that adult lactose tolerance is fairly common among Asians who grew up in the U.S.

Steve S. --  
 
Sorry to repeat, but "partly inbred extended family" just doesn't imply the same things at the gene level as clustering. There's more information in the latter. Imagine you land on an alien planet, and are told about the inhabitants that they form a "partly inbred extended family". That doesn't tell you as much as if I tell you how their genetic information is clustered, that correlations exist between, e.g., the color of their fur and the genes determining night vision, etc. (In a partly inbred extended family, there might or might not be any such correlations.) 
 
Also, a minor point: selection pressures are affected by culture as well as the local environment. Identical physical environments but differing societal structures might lead to selection for different traits. For example, in the same rainforest you might have one group practicing agriculture while the other sticks to hunting. The resulting selection on genes might be very different.

What I don't understand about Lewontin's viewpoint is that it is seems essential that the microsatellite markers he refers to be atypical. If I could simply choose some genes at random and find differences in allele distribution in a significant fraction of them between the different groups, he'd be harder pressed to trivialize it. I'm not an expert, but it seems to me the second scenario is more likely than what Lewontin suggests. At least, some of the language in the Risch papers suggests you don't have to look very hard to find robust clustering. That's also why the Chicago paper cited in the part III of the post above is interesting - it finds disjoint sets of genes under recent selection in different groups. Could an expert here comment on this? 
 
Regarding the difficulties in telling smaller sub-populations apart, this doesn't invalidate the overall concept. Just because pluto is problematic doesn't imply that there's no value in the categories "planet" vs "asteroid" or "comet". A category can fail in some difficult or extreme case while still capturing something useful in the more typical case. It's just poor logic to claim otherwise.

But (correct me if I'm wrong), isn't the more interesting question whether we'll eventually find clustering on other loci as well? Is there a plausible scenario where the observed clustering isn't accompanied by additional clustering on genes subject to selection?

Steve Sailor: your definition is easier for the average person to understand, but it doesn't imply the existence of subpopulations with significant gene frequency variations, which is most relevant to group differences in phenotype. Similarly, as Razib noted, it doesn't say anything about whether the distant branches of the family have been subjected to different selection pressures. The clustering observation implies this (that's likely how the clustering came about on so many loci - although I suppose it might also be due to founders or other small population effects). 
 
That is, a "partly inbred extended family" might or might not exhibit the clustering found. It doesn't resolve the present situation, for example, from one in which clustering is only on a few genes (e.g., for pigmentation and hair color), and in which it would be fair to say there is little content to the term "race". In the latter case "race" only tells you obvious things you already knew from just looking at the person. In the clustering case, it (statistically) implies much more about genes whose effect can't be seen superficially. 
 
There is much more information in the fact that clustering occurs on a large fraction of all genes. For someone who is a bit more sophisticated about math or genetics, it immediately tells them there might be significant group differences between the sub-populations which go beyond a few superficial features. For example, a population that satisfies your definition might or might not have differences in disease resistance, but it's highly likely from the cluster definition. 
 
Admittedly, none of this is easy for joe shmo to understand. You need some basic idea about conditional probability or statistics. "If Jane has the gene for straight black hair, she is more likely to have the disease-related gene X..." note this kind of statement is impied by clustering but not necessarily by your definition - it might be that distant branches of the family tree *only* differ in hair and skin color.

You guys already know this of course, but it doesn't really matter whether there is 100% overlap in the alleles for two groups, or even if the same set of alleles are common (occur with reasonably high frequency) in both groups. 
 
Even relatively modest differences in frequencies can lead to significant group differences if the trait in question is influenced by many genes. For example, suppose having the best variants of 7 different genes that affect brain function is the most likely cause of an off-scale IQ. Then, suppose in one group the best variant is found 15% of the time at each locus, but in the other group it's only 10%. Well, then one group will populate the tail of the IQ distribution much more than the other, as (.15)^7 >> (.1)^7, etc. This is oversimplified, but you get the point.

Constantine, 
 
I agree with you completely. Watson's comments concerning evolution and religion only make sense if applied to the most literal and fundamentalist readings of, e.g., the bible. Keep in mind he's been thinking about this topic his entire life. These guys only seem modestly clever to me. 
 
Most biologists don't seem to really understand evolution and its philosophical implications in a deep way. 
 
http://infoproc.blogspot.com/2005/02/evolutionary-timescales.html

Let me throw a simple question out there: What are all the components of a typical American IQ test? I only know of three, math, spatial, and verbal.

Modern technology and not immigrants make cities dangerous? I suppose its how you look at it. Wonder how this guy feels?

http://pub.tv2.no/nettavisen/en

Sheeee's Bengali?

"Figures show that black students of Caribbean origin got the worst results of any ethnic group in last summer's GCSE exams in England"

http://news.bbc.co.uk/1/hi/education/2816369.stm

Note the Chinese and Indian results. In the UK Indians, Pakistanis and Bangladeshis are all lumped together by white folks.

Razib, this is all very interesting stuff – highly speculative, of course, but also of some importance. When you say

“perhaps I could make one on the hunch that liberalism might never take root, that freedom would never flourish, without a phase where the culture, and populace, were scaffolded and guided by the Christian idea.”

It is important to determine just what the Christian “idea” is. I think we’ve looked at various ideas in Christianity which are compatible with the development of liberalism as well as the various historical, political, geographical and cultural elements that helped give rise to liberalism. I think it’s clear that we secularists can extract the sound ideas (the golden rule, the moral significance of the individual, the separation of church and state, emphasis on the spirit of the law, etc.) from Christianity and leave those that are superfluous or downright irrational. I don’t think that those countries already progressing toward liberalism need to adopt Christianity when they already have their own religious traditions, but it may be that those that aren’t do need Christianity, complete with its religious trappings.

As an aside, I’d like to ask you about the influences of East Asian (and to a lesser extent Indian) ideas on American culture. A few things have prompted this question: On NPR the other day, there was a story about Honda’s plant in Alabama and how Honda is exporting their corporate culture and ethic to America; the continued trendiness of Yoga, Buddhism and Zen; and the popularity of Pokemon, Yu-Gi-Oh and Jackie Chan among children. I couple Jackie Chan episodes I watched with my daughters were particularly enlightening. In one good and evil were turned around, the characters that possessed the stereotypes of good, turned out to be evil, while those with evil stereotypes turned out to be good. And a recurring theme is the balance between good and evil, as opposed to the Christianity’s neurosis concerning sin.

Finally, I need to stand up for “my people.” You write. “The stain of anti-Semitism is much darker upon the modern Eastern Church than that of the West-perhaps explaining some of the attitudes common in Russia (though western-leaning Catholic Poland also has a history of Jew-hatred, so this is highly disputable).” I want to point out a pretty iron clad law of anti-Semitism: The more Jews in a country, the more anti-Semitic the people are accused of being, with America being perhaps the only known exception. Prior to partition, about ¾ of all Jews in the world lived in Poland/Lithuania. Is it any wonder that Poles are morally condemned for anti-Semitism while the Irish, say, are largely free of this particular sin? It could be argued that Jews migrated in such large numbers to Poland because of Polish tolerance rather than Polish anti-Semitism. An
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I'd be hard pressed to come up with another nation that has had to endure as much shit over the last 2 centuries as Poland. Luckily Poles deal with it and try to move on.

Anyway, I'm quite struck between the a neo-Platonist like Plotinus and Buddhism, particularly Zen. Though Plotinus lived well after the golden age of Greece, I was unaware that there could have been much influence on him from Buddhism - I thought it was more coincidental. It's something I'll need to look into more.

As for the influence of Asian culture on the West, I think there's been a steady trickle since the 17th century Jesuits, but I think that in the upcoming centrury it will only increase, just by the weight of demographics and the relative power balance. Though the cultural diffusion may appear to be superficial and take on a combination of elements from both cultures, I have no doubt it will occur and the results will mostly be positive.

It would be curious that Pythagoras would have gone to India and have come back without the concept of zero. Perhaps with the reliance of Greek mathematics on geometry, Pythagoras did not see the significance and usefulness of such a concept.

I agree that from a purely philosophical point of view, ideas can arise independently in different times and different places. It may be tempting to posit Buddhist influence on Plotinus and Christian monastic traditions, but they could have risen with almost no cultural diffusion.

In How The Mind Works, Pinker also made an economic argument for why polygamy would benefit women. It does rely on women freely choosing that arrangement as opposed to being coerced. Would a woman rather be the second wife of a kind and wealthy man or the first wife of a drunken bum. It seems, with a free marriage market, the biggest losers would be the biggest losers.

Polygamy was part of Judaism until about the 10th century and most western nations have de facto serial polygamy.

I whole heartedly agree with michaelvassar on his point. It may be bigoted as Brandy says to claim that the great unwashed have difficulty accurately and sensibly interpreting facts, but it doesn't make it any less true.

It may also display a bit of arrogance to claim that we, the readers of gene expression, are "levelheaded" and can discuss emotionally charged issues rationally, while a great many people aren't and can't. But again, it strikes me as being somewhat true.

Finally I agree with Michael that there is often a tendancy to equate IQ with moral worth, and it is at this point that it's possible to flirt with more racist ideas.

"people with low-IQs often have trouble comprehending the complex, nuanced moral codes that the high IQ elites invent for themselves."

And people with high iq's are often adept at exploiting those moral codes and rationalizing their behaviour. If there were some sort of objective way to assess (or even define), the all purpose "moral worth" of an individual,M, I wonder how much it would correlate with g.

Not necessarily, Richard. It depends who he got shit from.

It's challenging trying to untangle cause and effect here. Specifically, does the reason protestant Europe has taken to liberalism more readily than Catholic Europe have much to do with the theological mumbo jumbo of Protestantism vs. Catholicism. Or is it that the reformation itself reflected more political independence already within protestant nations. Or that the process provided protestant nations with the opportunity to develop freer societies.

It could also be argued that the protestantism is somehow more "rational" than Catholicism. But there were/are some pretty nutty protestant sects and Catholicism today is far less anti-scientific than Southern Baptists and some other sects.

As for the broader question that Jimbo raises of Christianity's concept of the soul accountable to a God being more conducive to liberalism than Buddhism, I don't know enough about Buddhism to really answer that. I know that part of Buddhism is the belief that the self is an illusion (Western translation), but that's no different than one of Pinker's assertion in the blank slate, that the "ghost in the machine" or the soul is an illusion or many evolpsych's belief that free will is an "illusion."

It may that Eastern religions reflecting the collective effort of higher IQ individuals anticipates conclusions of Western science. Or it could be that since liberalism contains the notion of a soul axiomatically in its development ("endowed by their creator," evolution, "with certain inalienable rights"), that there really is such a thing as a soul. (Think of liberalism as a pragmatic, real world experiment of the hypothesis of the existence of the soul. It's worked, therefore there must be a soul.)

The next question is, if there's a soul, what the hell is it?

You can point to a lot of different influences throughout history that contributed to the development of liberalism. There are certainly elements of Christianity that contributed to liberal thought that are unique to Christianity. In relation to the other one bigguy religions, Christianity actually seems the most patently absurd. But it is may also be most appealing because Christianity is really about the GR, so you can take to it any which way you want.

The pagan influence on Christianity is obvious too, which makes it more easily adaptable to different cultures and different times and allows for equalizing mythologies to develop. An example is the emergence of the Virgin as major theme in Western art and consciousness around the 12th century, which may have played a moralizing force on Christianity[1]. Christian artists also captured and explored the human condition in all its pathos and tragedy, while Islam hypnotized itself with geometric abstractions. As a memetic organism, Christianity is a more clever adaptation to humans than what appears a more rigid Islam.

To take up a couple specific points:

To J Mc T. I’m in basic agreement, but would like to add a couple observations: “stupid to God” is a great way to abandon metaphysical navel gazing for practical, real world concerns. And the fact that Jesus didn’t deal at all the matters of state, or even of the physical world, investigation into these realms didn’t really contradict anything essential about Christianity. But what is it about Protestantism that mad it “no accident that liberalism started in a Protestant country, and that Protestant country was England?” I don’t think it had anything to do with Protestantism itself – the Church of England was more a political calculation than a theological schism.

To Jimbo: : “can liberalism survive without the social capital generated by an underlying Christian structure?” I agree this is a very interesting question and since parts of the West have already crossed into post-Christendom and non-Christian countries have developed broadly liberal societies, I would bet on yes.

To look at the question in more detail, we can use Razib broad definition of liberalism and ask what part of the “underlying Christian structure” is necessary to support it. Is it necessary that the core belief – the divinity of Jesus – be maintained? I certainly don’t see why that peculiar belief has any bearing on liberalism, but I do recognize the value of religion and the reality and legitimacy of spiritual concerns. I think that the religious impulse is so deeply ingrained in human nature, that the trick becomes not hope it somehow evolves out (or godless can engineer it out;-)) of humanity, but to develop more rational religious beliefs that satisfy human needs for community, ritual, mythology and a sense of awe, mystery and higher purpose. In E.O. Wilson optimistic vi
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Jimbo, the idea that a good many people do need the foundational doctrine of Christianity to adhere to its moral code runs parallel (though I think to the right, i.e. religion is a delusion conservatives purposely try to maintain) to the issue of human equality, the left's pet delusion. In each sense, there is an elite that, in the cynical words of Mencken, "preach doctrines they know to be untrue to men they know to be idiots."

I wonder how seriously most mainline Christians take the idea of Jesus' divinity. My guess is that a good many pay it lip service, but that the belief itself is really quite inconsequential to their general views on life.

It does raise the moral conundrum for those of us who think of ourselves as "rational secularists" of just how far we can and should push back veils of ignorance. I personally think truth is always better than delusion, but shattered delusions can lead to violent reactions. As Jung said, extremism is compensated doubt.

As the rest of the blog races on up ahead...

j McT, when you say that “there is absolutely nothing irrational about anything in Christianity at all. An irrational thing is logically impossible, i.e. a square circle or a married bachelor,” I think you have a very limiting definition of “irrational.” Would we say that Saddam Hussein is being rational if he says Iraq will crush the United States in battle? There’s certainly no logical contradiction, but it sure isn’t my idea of a rational belief. An irrational belief is a belief that contradicts empirical evidence, rests upon faulty reasoning or is non-verifiable yet held with powerful emotional commitment. The dichotomy between the rational and irrational isn’t as clear cut as that between the logical and the illogical.

The core belief of Christianity, the unique divinity of the historical figure Jesus, strikes me as irrational because it is a rather extraordinary claim with no evidence to support it, other than some second hand accounts written well after his death. I know plenty of rational people who believe it, but as a matter of politeness I don’t press the issue. Incidentally, I don’t find strict materialism particularly rational either for the simple reason that by a materialist’s own admission, his ideas aren’t real and therefore not worth considering.

I think you underestimate the pagan influence on Christianity as well as the pagan compatible doctrine of the trinity. Christianity evolved over time a pantheon with Christ at its center, but plenty of other lesser gods and goddesses in the form of saints and icons, and especially in the form of the Virgin Mary. Even today, you can walk in the woods and country sides of many Catholic nations and see shrines to various saints. Protestantism was to some extent an explicit rejection of what many reformers came to think as Catholic paganism. This may have had a rationalizing effect on Protestantism by making God even more abstract than in Judaism, but at the cost of a rich and humane mythology.

Whether or not liberalism needs Christianity to survive depends on what you mean by Christianity – the doctrine of the moral equality of all men or the doctrine of the death and resurrection of Jesus. I’m still of the mind that liberalism is a rational social structure and therefore compatible with a variety of cultures, including non-Western and non-Christian or post-Christian ones. But my concern is, if these doctrines aren’t seen as independent, many people will come to reject Christian morality based upon the rational rejection of Jesus’ divinity. So as a matter of salvaging what’s necessary, Christianity needs to abandon what will only become a more divisive and untenable position. The problem is that different people and different parts of the world are at wildly different stages of moral develo
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