Abstact of the article in question, which has promted commentary inthe Economist and the NYT:

Journal of Biosocial Science (2005), :1-35 Cambridge University Press
Copyright © Cambridge University Press
doi:10.1017/S0021932005027069
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Regular Articles

NATURAL HISTORY OF ASHKENAZI INTELLIGENCE

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GREGORY COCHRAN a1 , JASON HARDY a1 and HENRY HARPENDING a1

a1 Department of Anthropology, University of Utah, Salt Lake City, USA

Abstract

This paper elaborates the hypothesis that the unique demography and sociology of Ashkenazim in medieval Europe selected for intelligence. Ashkenazi literacy, economic specialization, and closure to inward gene flow led to a social environment in which there was high fitness payoff to intelligence, specifically verbal and mathematical intelligence but not spatial ability. As with any regime of strong directional selection on a quantitative trait, genetic variants that were otherwise fitness reducing rose in frequency. In particular we propose that the well-known clusters of Ashkenazi genetic diseases, the sphingolipid cluster and the DNA repair cluster in particular, increase intelligence in heterozygotes. Other Ashkenazi disorders are known to increase intelligence. Although these disorders have been attributed to a bottleneck in Ashkenazi history and consequent genetic drift, there is no evidence of any bottleneck. Gene frequencies at a large number of autosomal loci show that if there was a bottleneck then subsequent gene flow from Europeans must have been very large, obliterating the effects of any bottleneck. The clustering of the disorders in only a few pathways and the presence at elevated frequency of more than one deleterious allele at many of them could not have been produced by drift. Instead these are signatures of strong and recent natural selection.

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closure to inward gene flow led to a social environment in which there was high fitness payoff to intelligence, specifically verbal and mathematical intelligence

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But where is the evidence that these particular abilities led to an increase in offspring?

Evolution works by selecting for certain traits. But that means that those traits have to provide a payoff in terms of the number of offspring wwho survive.

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Originally posted by jeff house:
[QB]

But where is the evidence that these particular abilities led to an increase in offspring?

Evolution works by selecting for certain traits. But that means that those traits have to provide a payoff in terms of the number of offspring wwho survive.
[QB]

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Read the paper:

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Jews who were particularly good at these jobs enjoyed increased reproductive success.
Weinryb (1972, see also Hundert 1992) comments: “more children survived to adulthood
in affluent families than in less affluent ones. A number of genealogies of business
leaders, prominent rabbis, community leaders, and the like—generally belonging to the
more affluent classes—show that such people often had four, six, sometimes even eight
or nine children who reached adulthood. On the other hand, there are some indications
that poorer families tended to be small ones. It should also be added that overcrowding,
which favors epidemics was more prevalent among the poorer classes. In short, the
number of children surviving among Polish Jews seems to have varied considerably from
one social level to another.” He goes on to suggest that wealthier Jews were less
crowded as they lived in bigger houses, they could keep their houses warmer, they could
afford wet-nurses, and they had better access to rural refugia from epidemics. As an
example, in a census of the town of Brody in 1764 homeowner households had 1.2
children per adult member while tenant households had 0.6.

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On the other hand, there are some indications that poorer families tended to be small ones. It should also be added that overcrowding, which favors epidemics was more prevalent among the poorer classes. In short, the
number of children surviving among Polish Jews seems to have varied considerably from
one social level to another.

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This sounds a lot like anecdotal evidence. Is there anywhere is the world that confirms this?

My perception is that it is the poorest countries in the world that have the largest families.

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A number of genealogies of business
leaders, prominent rabbis, community leaders, and the like—generally belonging to the
more affluent classes—show that such people often had four, six, sometimes even eight
or nine children who reached adulthood. On the other hand, there are some indications
that poorer families tended to be small ones.

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"There are some indications that poor families tended to be small ones."

And the evidence that "business leaders" "and "THE LIKE" were more intelligent than poor people?

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Originally posted by jeff house:
[QB]I think that's pretty weak.

"There are some indications that poor families tended to be small ones."

And the evidence that "business leaders" "and "THE LIKE" were more intelligent than poor people?

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It's in the paper:

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Detailed demographic data about early medieval Ashkenazim are lacking, but we can
infer plausible parameters from the scarce information that we do have. First, their jobs
were cognitively demanding since they were essentially restricted to entrepreneurial and
managerial roles as financiers, estate managers, tax farmers, and merchants. These are
jobs that people with an IQ below 100 essentially cannot do. Even low-level clerical jobs
require something like an IQ of 90 (Gottfredson, 2003).

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(Gottfredson, L. (2003) g, jobs, and life. In Nyborg, H. (ed.) The Scientific Study of
General Intelligence, Elsevier Science, Oxford, pp. 293–342.)

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To me, this is a little story they made up, not serious social science.

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Originally posted by maestro:

This sounds a lot like anecdotal evidence. Is there anywhere is the world that confirms this?

My perception is that it is the poorest countries in the world that have the largest families.

Can you point to any study that provides evidence that richer people are more prolific?

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Did you read to the end of the quote?

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As an
example, in a census of the town of Brody in 1764 homeowner households had 1.2
children per adult member while tenant households had 0.6.

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Your opinion doesn't count for much since you rather obviously have not read the paper.

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I began to read it, but found it to be highly dubious. So, I stopped reading.

You reproduce a typical bit:

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Detailed demographic data about early medieval Ashkenazim are lacking, but we can
infer plausible parameters from the scarce information that we do have. First, their jobs
were cognitively demanding since they were essentially restricted to entrepreneurial and
managerial roles as financiers, estate managers, tax farmers, and merchants. These are
jobs that people with an IQ below 100 essentially cannot do.

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I agree with the first part: data are lacking.

As for the second part, I would never make an argument for racism based on "plausible" parameters.

Many things are "plausible". Most of them are nonetheless untrue. Is it plausible that I am wearing grey pants? Of course it is plausible.

But is it therefore a basis for theorizing about my taste in clothes? No, because as it happens I am wearing blue jeans.

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As for the second part, I would never make an argument for racism based on "plausible" parameters.

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It isn't an argument for racism.

The data is far more than plausible; in its totality, it is quite persuasive.

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One possible area of confusion; the authors do not think that wealth is associated with large families today, but rather in the time in which the selection is supposed to have taken place, prior to the 18th century.

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COLUMBUS, Ohio, Aug. 21 -- The following was released today by the Center for Public Information on Population Research:

Recent findings could add new fuel to age old sibling rivalries.

Children from larger families accumulate less wealth in adulthood than do those from smaller families, according to a study of adults in their late 30s and early 40s published in the current issue of the journal Demography.

On average, individuals from "only child" families were the wealthiest in adulthood, and wealth declined steadily with each additional child in the family, reports Lisa Keister, an Ohio State University sociologist.

"Family size matters: Siblings dilute the finite amount of money and time parents can devote to each child, " explained Keister. "Having fewer resources limits educational attainment, and reduces financial transfers from parents to children such as help with tuition, a down payment on a house or inheritances."

She found that individuals from larger families were less likely to own either a home or stocks as adults and also less likely to receive a trust fund or an inheritance...

...Growing up in a family of four or more children seemed to put a person at a greater economic disadvantage, she noted.

..."Having wealthy parents, earning a college degree, and buying stock all increased an individual's changes of being wealthier than average in adulthood," she said. "But those from smaller families still had more of an advantage."

The research was supported by the American Sociological Association and Ohio State University.

Demography is the peer-reviewed journal published by the Population Association of America. The full article, "Sharing the Wealth: The Effect of Siblings on Adults' Wealth Ownership" is available on http://www.prb.org/cpipr. Or call the Center for Public Information on Population Research, 202-939-5414. The Center, a project of the Population Reference Bureau, is funded by the National Institute on Child Health and Human Development.

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Now there's something that seems to show that the larger the family, the less resources for each child, the less likely the child will be wealthy.

In other words, wealth is not an evolutionary 'fitness' selector in that larger families dilutes that which supposedly makes them more 'fit'.

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Diamond didn't come up with much in the way of solutions in Collapse, that's true, but the problem isn't reason per se, it's reason being used for ir-rational purposes like greed, revenge and self glorification. All ancient and sometimes profitable vices...

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from the previous thread.

But he did come up with many examples of how collective action was successful. He suggests that even among those that weren't successful they had the potential to succeed but conciously opted for the wrong solution. It is a moral lesson for us all.

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Here's a bit of a study that seems intuitively correct re: family size and wealth:
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Statistics show that where populations are wealthier birth rate drops. Which supports maestro's post. (See Carl Sagan's Billions and Billions).

When I was young I was put in a gifted class of adolescents and while there where many intelligent people there was a wide range of marks and in general the class was too competitive and self obsessed to function as a friendly learning environment. The next year I opted to move to another school where there were no "gifted" classes and enjoyed far more the class where there were a wide range of abilities and the material was interesting because of efforts of teachers to make things enjoyable. There was the added uplift of a new school amd starting out on a new adventure. There was a kind of equality among all that was very liberating. In the following year the drive to conventionalize the school took over. People were hunting for traditions,fraternities and sororities were started. Little cliquey groups started up. Additionally more authoritarian administration started to crack down on the 60's revolution that was showing more and more in the schools. My grades dropped and so did many others of people I knew. In fact it got even worse the following year with abusive teachers being fired and many students dropping out altogether (including myself). The following year after working in the real world I again went to a new school that was in its second year and again my marks improved in an environment of common communal interest. There were good and bad students but there was a sense of community which I thrived on. Did my IQ change in these periods? I doubt it. It is above average (but not mensa material I'm sure). I have to work at things and do not like to be frustrated by mean spirited competitive environments. In this I am not alone.

Now imagine that you the member of any group that is discriminated against. Would you not absolutely hate anu type of intellectually competitive environment that was also completely bigoted and unfair? Of course, what would you do to accomodate the groups need for individual and collective self esteme? You would develop your own learning environment and seek resources to support it. In time it would "pay off" and develop skills that could allow people to suceed outside your "small town ethnography". Does this make the genetic profile of your group which may be a simple statistical anomalie superior to some other group with a different set of environmental challenges? I don't think so. It is largely a simple coincidence.

The problem with prejudice is that attitudes about race and intelligence are almost instinctual themselves. People all over the world, as Jared Diamond points out are virtually genetically identical but on a cosmetic level they are different. Kinship is an important feature of human civilization and as silly as it may sound simple things like appearance mannerisms, dialect etc all are ways in which people define kinship.

Take another example of supposed genetic traits in population, Durkheim's book on suicide, strangely enough, titled "Suicide". I am summarizing, but he found that there was really no genetic or even individual predisposition for suicide. It was not significantly predicted by things like climate or weather patterns, full moons, but was largely the product of social forces. In other words societies often drove people to suicide. Benignly and conciously as in some cases like the myth of elderly Inuit walking off into a blizzard or chief Dan George stating, "It's a good day to die"; and more sinisterially by encouraging rational sane people that it is their only option.

Racism is I belive a similar response to social conditions. It is a way to externalize fear or concern in society. It creates an enemy and is society's way of externalizing internal doubts and contradictions. In the modern world however, this externalization often occurs within the boundaries of the nation state or the metropolis (See Gangs of New York - the movie... er maybe not)

Science is not neutral and has often acted in the name of some bogus principle, for example, the sterilization of the developmentally handicapped people in the early 20th century was first practiced in the US and Canada. Hitler and the Nazis borrowed this idea.Has this science the science proved effective? uh - no.

Domestication of animals has given us cows - animals unlikely to survive on their own in the wild as a species but genetically "superior" for human purposes. Maroon a colony of say, stock brokers, academics, or entrepreneurs on a south sea island - the human domesticate equivalent of cows - and see how long they last as an ethnographic "group". My prediction is that unless their inate aptitudes were very broad and they had personalities and attitudes that were open and felexible they wouldn't survive.

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Originally posted by maestro:

Now there's something that seems to show that the larger the family, the less resources for each child, the less likely the child will be wealthy.

In other words, wealth is not an evolutionary 'fitness' selector in that larger families dilutes that which supposedly makes them more 'fit'.

So the circle of more intelligence, more wealth, more children, more intelligence, more wealth, etc. is broken by the fact that more children means less wealth.

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The resources cited come from the present. The selection the authors are talking about happened in the last 1,100 years, but prior to the 18th century. Population dynamics have changed beyond all recognition since the advent of industrialization. I recommend the paper which goes into the hows and whys of greater fecundity and survivorship being related to wealth in Jewish (and other) communities prior to the 18th century (and they cite other scholars, which I have not read, as further support for this idea). Any standard work on population dynamics and history will talk about the drastic changes over the last few hundred years.

As for the "cycle" of wealth; it is not necessary and probably not desirible for the childern of the intelligent/wealthy businessperson to inherit wealth. If they did, the selective pressure for intelligence would be blunted in the suceeding generations. Ideal would be just enough wealth and prosperity to raise many surviving childern to adulthood, who inherit no wealth and are then force to suceed or fail (and have large or small families of their own) based on their only ability to prosper in business.

Thanks for fwding the whole report RSF, but, as others have already stated, it's long on speculation and short on real science; not one of the necessary links are established. The Sephardim weren't actually MiddleEastern Jews but became a distinctive people within Europe as well, doing many of the same occupations and facing similar social pressures and isolation as the Ashkenazim did --perhaps more so--- as did American blacks and Indians etc etc. New Guineans aren't really a measurable "population" either, the thousand ancient tribes just share some common morphological and genetic features as to be expected. As has been argued already, unless a study can reliably factor out all other possible causes for supposed differences within human populations (or whatever) then it's not even a valid theory.

Ah well, it was a interesting little sideline while it lasted. Maybe I'll send a letter to the NYT and Globe to let them know they've been victims of an elaborate hoax.

[ 08 July 2005: Message edited by: Erik the Red ]

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Thanks for fwding the whole report RSF, but, as others have already stated, it's long on speculation and short on real science; not one of the necessary links are established.

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I have two questions; do you have any scientific background which enables you to judge what is or is not "real science"? Beacause actual scientists are not nearly so dimissive of this carefully argued paper.

Second, have you taken the time to read the article? I know it's rather long, but it is not, in reality, long on speculation and short on facts. The evidence presented is quite varied and persuasive. They have clearly met the burden necessary to warrent further testing of their hypothesis, and like good scientists, they've outlined how to perform such tests.

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Ah well, it was a interesting little sideline while it lasted. Maybe I'll send a letter to the NYT and Globe to let them know they've been victims of an elaborate hoax.

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You know, some veteran babblers have been referencing this thread as an example of how interesting ideas degenerate into pissing matches. I certainally feel some guilt in relation to that and have resolve to do better. Therefore let me politely suggest that comments like the above are unwarrented. Your frustration at science you don't like but have no basis to dispute is clear, but that is no reason to give up and gloat at nonexistant victories over the studies' authors.

[ 08 July 2005: Message edited by: rsfarrell ]

All the people who ideological blinders convince them that there must be something wrong with the argument, even if time and time again their objections are shown to be fully answered by the text they have not bothered to read, could post their dissmisive non-arguments there.

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rsfarrell:
Your objections are emotional and ideological rather than rational or scientific.

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Originally posted by Vigilante:

LOL,of course historically those things have been sooo mutually exclusive

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You'll always have your Creationists, your social Darwinists, your geocentrists, your earth-is-flat crowd, your global-warming-is-just-an-unproven-theory crowd.

The dismissiveness people are showing to this research is not at that level of seriousness because it is for the moment just a hypothesis, not a theory.

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Originally posted by iPod:
Why are you trying to make an argument to justify your disgusting bigotry and hatred? Your obviously no better than the fucks who did this racist study, and your true intentions are clear you bigoted, hate-filled piece of shit. Take your hatred to the dark side, we dont need this shit here.

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Originally posted by rsfarrell:

Case in point. Read the paper, moron.

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Originally posted by Erik the Red:
This isn't science in the first place RsFarrell, it fails on all counts. You seem to be a bright guy but if you want to persist on this line you better offer some real substantive arguments or better yet just drop it.

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Support your claim. How is it not science? It makes observations, advances a possible explanation, supports it with many different kinds of evidence, and provides further means of testing the hypothesis to support or refute it. How is it not science?

As to "substansive arguments." I have gone back to the paper again and again to provide you and others with evidence and a correct understand of the arguments. But it is not my job to spoon-feed you an entire 40 pages of a closely argued genetics paper.

I spend twenty minutes creating a post quoting the relevant parts of the post refuting specious objections, and then someone else who hasn't read the paper says "what about X" and I spend another twenty minutes linking to those paragraphs. It's like playing pick-up-the-spoon with a three-year-old.

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Originally posted by iPod:

Im not reading that shit, and i dont need to, i already know that disgusting propaganda for what it is: total shit and lies.

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The data is far more than plausible; in its totality, it is quite persuasive.

Your objections are emotional and ideological rather than rational or scientific. Try looking at the whole picture.

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Try looking at what the authors wrote. They said that "Detailed data are lacking". They then said that they were basing their analysis on "plausible parameters".

If something is plausible, it may or may not be true. It is far from the hard data required, which in this case are "lacking".

You may think that their work is "far more than plausible". I don't. I think it is a just-so-story dressed up in scientific language.

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Originally posted by rsfarrell:

Support your claim. How is it not science? It makes observations, advances a possible explanation, supports it with many different kinds of evidence, and provides further means of testing the hypothesis to support or refute it. How is it not science?

As to "substansive arguments." I have gone back to the paper again and again to provide you and others with evidence and a correct understand of the arguments. But it is not my job to spoon-feed you an entire 40 pages of a closely argued genetics paper.

I spend twenty minutes creating a post quoting the relevant parts of the post refuting specious objections, and then someone else who hasn't read the paper says "what about X" and I spend another twenty minutes linking to those paragraphs. It's like playing pick-up-the-spoon with a three-year-old.

So, new rules. Any objection that is not directly answered in the paper I'll be happy to answer. If you want a summery of the argument and evidence I'll do that. Anything else, I'll refer people to the paper and its sources.

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Then Address what others have said to support Your Own claims RS. I just pointed out the historical fact that Sephardim were fellow European travellors, something neither you or the author were apparently aware of, therefore part of the theory falls apart right there. I will also point out that Jared Diamond himself, to his credit, rejects all the previous attempts to classify "blacks" as dumber on average based on IQ tests. Right before that bit about New Guinea we quibbled over earlier. I can post it if you like. I can also point out that these conditions mentioned are mostly fatal before adulthood except one, and lo and behold, effect only a small part of the Ashkenazi themselves, even if larger per capita than others, therefore another part of this theory falters. I can post that too. And if this IS unique to that very much mixed population then it tells us next to nothing about human populations in general and is very unlikely candidate for explaining the evolution of common human intelligence to any appreciable extent. All it does is open the door to more of this kind of unhealthy speculation. Sociology can tell us alot about these kind of things too, for example, that most of the genetic mixing between Jews and other Germans, Litvaks, Russians and Poles (some "Ashkenazi" coming from other small groups too, like the Lithuanian "Karaites") would have gone into the Jewish population, not the other way around as the authors speculate, and therefore would have had more effect on "dilluting" their eventual results, as I said earlier. That's actually quite well established historically, women of the weaker ethnic group will be the ones being raped regularly, and these women will be the ones having to decide whether to raise the potential results. Most the "fathers" will just move on in their ignorance. See why I'm sceptical?

Edited for my usual typos and to add a couple bits.

[ 08 July 2005: Message edited by: Erik the Red ]

OK, leaving aside the meagre data, my considerable doubt that this population was isolated enough for any meaningful dynamic to be playing out, the short time frame evolution-wise, and the questionable aims of the researchers--
What is this shit about rich people being smarter? Yeah, right. Rich people get more empowering, and therefore intellectually demanding and enriching, jobs in every culture, as well as having more access to education. And in every culture they seem to think that means the lower classes are inferior morons who are only downtrodden because "they deserve it". Doesn't make them right.

Again, this is essentially the Bell Curve argument, which was fairly explicit in claiming that poor people were poor because they were stupid rather than admitting that poor people were uneducated because they were poor, and did poorly on IQ tests because uneducated people do worse on so-called "Intelligence" tests. It was a classist "blame the victim" strategy with the additional bonus that they were then able to recommend a "punish the victim" course of action (sterilize the poor&stupid lest they outbreed us)--the racism was almost the icing on the cake, really.

And indeed, I can see this study connecting up beautifully with the whole "Bell Curve" eugenics idea. Here's the schtick: When poor people had small families, the Ashkenazim got smarter. Nowadays, poor people have bigger families & are making tons of stupid people! Be afraid of the great unwashed stupidity! So the only solution is to limit the proles' (especially black proles') breeding so that we can instead get an Ashkenazim-type situation with more smart, rich people. It will improve the Volk!

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Originally posted by Erik the Red:

Then Address what others have said to support Your Own claims RS. I just pointed out the historical fact that Sephardim were fellow European travellors, something neither you or the author were apparently aware of,

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Do you have any support for this statement? And have you read what the paper says about Sephardim? It talks about their distribution at some length. Once again you are judging the paper without having read it.

In modern times, the Sephardim overwhelmingly resided in the Middle East and North Africa. Some also lived in Europe and the Americas. I didn't know that, but it hardly damages the author's argument, since the Sephardim lived under Islamic conditions during much of the period discussed and most of them continued to until the colonization of Palestine. Hence, Ashkenazi Jews are unquie in the selection pressures to which they are subject.

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therefore part of the theory falls apart right there. I will also point out that Jared Diamond himself, to his credit, rejects all the previous attempts to classify "blacks" as dumber on average based on IQ tests. Right before that bit about New Guinea we quibbled over earlier. I can post it if you like.

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That's fine. It would be nice to see you use some evidence to support your assertions. As to the relationship of IQ to intelligence, I refer you to the paper.

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I can also point out that these conditions mentioned are mostly fatal before adulthood except one, and lo and behold, effect only a small part of the Ashkenazi themselves, even if larger per capita than others, therefore another part of this theory falters. I can post that too.

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And when and if you do, you will only have established that you don't understand how heterozygote advantage works. Sometimes two copies kill you while one copy helps you.

As for the number affected, that's totally irrelevant to the theory. Besides which, when you add up all these diseases, and consider that there are always many heterozygotes for each homozygote, and the fact that there may be similar intelligence-enhauncing genes without disease-causing side effects, the numbers are plenty big enough to matter.

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And if this IS unique to that very much mixed population then it tells us next to nothing about human populations in general and is very unlikely candidate for explaining the evolution of common human intelligence to any appreciable extent.

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This is the kind of statement that just confuses me. Where do they say they are explaining the evolution of human intelligence? They don't. Naturally it's interesting, and there is no reason why sigular exceptions cannot teach us about general principles. It happens all the time in science. For example, identical twins get adopted by seperate families and live independant and ignorant of one anothers' existence. That is a very unusal circumstance, but its been used to learn a lot about genetics and behavoir. In biology it's called a natural experiment.

And, BTW, the authors' point out in several places that the circumstances of the Ashkenazi Jews are probably unquie in human history.

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All it does is open the door to more of this kind of unhealthy speculation.

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"Unhealthy," huh? Your biases are showing. In fact, it makes testible predictions. So we can do more than speculate; we can test the theory. There's also neurochemistry to be done (some of the beginnings of the investigation are described in the paper) to work out how these genes improve verbal and mathematical skills. So there's a lot of science to be done, as well as the inevitable speculation.

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Sociology can tell us alot about these kind of things too, for example, that most of the genetic mixing between Jews and other Germans, Litvaks, Russians and Poles (some "Ashkenazi" coming from other small groups too, like the Lithuanian "Karaites") would have gone into the Jewish population, not the other way around as the authors speculate, and therefore would have had more effect on "dilluting" their eventual results, as I said earlier. That's actually quite well established historically, women of the weaker ethnic group will be the ones being raped regularly, and these women will be the ones having to decide whether to raise the potential results. Most the "fathers" will just move on in their ignorance. See why I'm sceptical?

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And the paper explains that genetic inflow is less than 0.5% per generation according to established genetic markers, and that level is consistant with the poisted genetic changes. You get what I'm saying? We don't need to speculate about Cossacks and cuckolds when we can actually sample the gene pool and infer the level of inflow.

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Originally posted by Rufus Polson:
Let me get this straight. The argument seems to be that
--rich Ashkenazi Jews were reproducing more than poor ones
--the rich ones occupied intellectually demanding jobs, while the poor ones did not
--that means the rich ones must have been in those jobs because they were smarter,
--and therefore smart people were reproducing faster than dumb people in that population

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I cannot thank you enough for attempting to paraphase the argument, because I can deal directly with the way you've misunderstood it, and not bother with the rest. Saves no end of time.

-- Yes, the rich were reproducing more than the poor.

-- No, it is not true, according to the authors, that "the rich ones occupied intellectually demanding jobs, while the poor ones did not." Both rich and poor were overwhelmingly forced into intellectually demanding jobs because others were forbidden them.

-- No, it is not true, according to the authors, that "that means the rich ones must have been in those jobs because they were smarter." Rather, the idea is that smart people did better in the same jobs, and because they did better, they made more money, and because they made more money, they had more surviving kids.

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Originally posted by jeff house:

Try looking at what the authors wrote. They said that "Detailed data are lacking". They then said that they were basing their analysis on "plausible parameters".

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In the real world, you do not have an infinite amount of error-free data. You have a limited amount of noisy data. In some part of their argument they use "plausible parameters" in some parts "detailed data are not availible." That in no way refers to the argument as a whole, which is constructed out of a large amount of evidence, some circumstanial, some direct, all pointing in the same direction. All completely normal in a scientific hypothesis.

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If something is plausible, it may or may not be true. It is far from the hard data required, which in this case are "lacking".

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Again, you haven't read the paper, so you aren't familiar with the pages and pages of "hard data" they present, or the scores of scientific and historical studies they cite.

By treating the adjectives in that one part of the argument as if it were the whole argument, you are employing a straw man fallacy.

You should also realize that everything in science "may or may not be true" therefore having that quality does not, in itself, discredit an idea.

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You may think that their work is "far more than plausible". I don't. I think it is a just-so-story dressed up in scientific language.

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So a non-scientists has decided a paper (which he hasn't read) is just a "story" "dressed up in scientific language," and if the folks at the NYT, the Economist, and the Journal of Biosocial Science (Cambridge University Press) think differently, well, what do they know?

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Now explain to me why what I have just said is "emotional and ideological". If you can't, withdraw the accusation.

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I think I just did. No scientific objections, just and passionate and irrational hostility towards something you haven't read and don't understand.

[ 09 July 2005: Message edited by: rsfarrell ]

And, rsfarrell: I understand your frustration with some reactions, but please refrain from comments like "Read the paper, moron." Given the subject matter, that last word is especially unhelpful.

A complaint has been made about this thread. I'm not shutting it down now, because I think that it (so far) falls within the bounds of what can and should be discussed in a forum such as this one. If the paper is "junk science", or is misguided in its motivations, methodology or conclusions, then anyone is welcome to make that case.

Meanwhile, let's try to be civilized.

[ 09 July 2005: Message edited by: Albireo ]

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-- No, it is not true, according to the authors, that "that means the rich ones must have been in those jobs because they were smarter." Rather, the idea is that smart people did better in the same jobs, and because they did better, they made more money, and because they made more money, they had more surviving kids.

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Gonna go out on a limb here, because I haven't read the paper either, but how could anyone know that the people who succeeded in these jobs did so because they were "smarter" (whatever that might mean)? Perhaps they did well because they were more ruthless. If that was the case, then they would be richer as a result of their lack of morals, have more children, and the population in question would be genetically filled with a lack of ethics, if that makes any sense at all (and I kinda doubt it does).

I'll only say that intelligence need not be the only factor in order to be selected for; it need only be one of the factors. If a large beak helps a population of birds get the availible seeds, it doesn't matter that their brain size and visual acuity and wingspan also help them find seeds; there will still be selection for a larger beak size (as well as any other signifigant heritable factors.)

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So, as one factor that helps in these careers, intelligence could be selected for, even though, as we all know, there's more to success in business than smarts.

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This goes to show how far off track the whole thing is.

When someone starts equating 'intelligence', a pretty arbitrary concept, with smarts, and even more arbitrary concept, rationality has left the building.

I have read the paper, and intend to re-read it several times, but what I see so far is a very shaky link between 'intelligence' and fecundity.

The authors spend a lot of time examing this and that, but they must show that there is an intelligence gene, that the intelligence gene was selected for, and that the intelligence gene was spread through the population by the their hypothetical method, which is that the wealthy were able to raise more children to adulthood than the poorer, thus spreading it through the population.

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You should also realize that everything in science "may or may not be true" therefore having that quality does not, in itself, discredit an idea.

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You should realize that ideas have consequences. And an idea which may or may not be true, one based upon a history in which "data is lacking", is an idea I won't incorporate into my life understanding.

And your debating style is dishonest, too. You place this article on the website, and invite comment. When I comment, you claim that object that I am "a non-scientist" and disqualified from holding an opinion.

I will explain something to you. Lawyers deal in evidence. We are often quite knowledgeable about evidence. We know that a theory based on a lack of data cannot be relied upon.

You say that "in the real world, there is not an infinite amount of error-free data."

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Originally posted by jeff house:
You should realize that ideas have consequences. And an idea which may or may not be true, one based upon a history in which "data is lacking", is an idea I won't incorporate into my life understanding.

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Maybe we could start with something more modest than incorporation into your life understanding. Maybe you could look at the evidence presented and consider the possible explanations for it.

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And your debating style is dishonest, too. You place this article on the website, and invite comment. When I comment, you claim that object that I am "a non-scientist" and disqualified from holding an opinion.

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You mean dishonest like taking the phrase "data is lacking" out of context and pretending it applies to the entire hypothesis is dishonest? Dishonest like that, or dishonest in another way?

What I object to is not that you hold an opinion, or even a negetive opinion. It is that, proir to reading the article, you decided it was un-scientific, despite the fact that is was published in a respected scientific journal, put out by a respected academic publisher, and respectfully if not warmly reviewed by the NYT and the Economist, who might have noticed that were devoting column inches to junk science.

Now, it might still be terrible science. Anything's possible. But that you would make such a claim, without any expertise in science, and without having read the whole argument, I found dubious in the extreme. I had a problem with that one claim, not with your having an opinion.

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I will explain something to you. Lawyers deal in evidence. We are often quite knowledgeable about evidence. We know that a theory based on a lack of data cannot be relied upon.

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Would you ever argue against an opposing brief without having read it? If a non-lawyer told you a federal appeals count decision was "terrible, not legal reasoning at all" how much credibility would you give that assessment?

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You say that "in the real world, there is not an infinite amount of error-free data."

Well, that's a straw man, of course, since no one said you need "infinite" data. But here is the difference between you and me: when there is not enough reliable data, I prefer silence to speculation.

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And I prefer science to silence. They have enough reliable data to form a scientific hypothesis. That hypothesis makes testable predictions. Design experiments around those predictions and you'll support or refute the hypothesis. So on what basis do you say that there is not enough reliable data?

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The authors spend a lot of time examing this and that, but they must show that there is an intelligence gene, that the intelligence gene was selected for, and that the intelligence gene was spread through the population by the their hypothetical method, which is that the wealthy were able to raise more children to adulthood than the poorer, thus spreading it through the population.

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The authors' are not poisting an "intelligence gene" but rather many genes which improve verbal or mathematical reasoning, some of which have disease-causing side effects.

And they do a pretty good job. Did you read the analysis of the patients of the Gaucher Clinic in Jerusalem? Pretty interesting, especially in light of the reports reguarding patients with torsion dystonia and congenital adrenal hyperplasia.

[ 09 July 2005: Message edited by: rsfarrell ]

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Originally posted by Fidel:
If rich white people are more intelligent, then how do they explain president Dubya ?. Sure he was allowed in to Harvard and Yale because of his family connections, but he's an idiot. And so are his brothers. So much for Prescott Bush's personal crusade for eugenics because he should have been castrated himself.

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And I prefer science to silence. They have enough reliable data to form a scientific hypothesis. That hypothesis makes testable predictions. Design experiments around those predictions and you'll support or refute the hypothesis. So on what basis do you say that there is not enough reliable data?

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So after all that, the result is that they are only offering a hypothesis? They are in no way claiming that it is correct?

OH! And here I thought that you were trying to tell us that this was true!

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So after all that, the result is that they are only offering a hypothesis? They are in no way claiming that it is correct?

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This is what I'm talking about. You don't understand how scientists use these terms. Because something is a "hypothesis" does not mean people are "in no way claiming that it is true" any more than Creationists are correct to saying that evolution is "just a theory" and therefore "unproven."

A theory is a hypothesis that has been tested over and over and found to be correct. It is often a complex system of scientific principles built up, modified and refined over generations. No, this hypothesis is not at the level yet, which doesn't mean it's not correct. I'd give good odds that, although it will probably be refined, that this idea about Ashkenazi diseases and intelligence will become part of the theory of human genetics. We'll see.

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Biology of the Sphingolipid Mutations
The sphingolipid storage mutations were probably favored and became common because
of natural selection, yet we don’t see them in adjacent populations. We suggest that this is
because the social niche favoring intelligence was key, rather than geographic location. It
is unlikely that these mutations led to disease resistance in heterozygotes for two reasons.
First, there is no real evidence for any disease resistance in heterozygotes (claims of TB
resistance are unsupported) and most of the candidate serious diseases (smallpox, TB,
bubonic plague, diarrheal diseases) affected the neighboring populations, that is people
living literally across the street, as well as the Ashkenazim. Second and most important,
the sphingolipid mutations look like IQ boosters. The key datum is the effect of increased
levels of the storage compounds.

Glucosylceramide, the Gaucher storage compound,
promotes axonal growth and branching (Schwartz et al., 1995). In vitro, decreased
glucosylceramide results in stunted neurons with short axons while an increase over
normal levels (caused by chemically inhibiting glucocerebrosidase) increases axon length
and branching. There is a similar effect in Tay-Sachs (Walkley et al., 2000; Walkley,
2003): decreased levels of GM2 ganglioside inhibit dendrite growth, while an increase
over normal levels causes a marked increase in dendritogenesis. This increased
dendritogenesis also occurs in Niemann-Pick type A cells, and in animal models of Tay-
Sachs and Niemann-Pick.

Figure 1, from Schwartz et al. (1995) shows the effect of glucosylceramide, the sphingolipid
that accumulates in Gaucher disease. These camera lucida drawings of cultured
rat hippocampal neurons show the effect of fumonisin, which inhibits glucosylceramide
synthesis, and of conduritol B-epoxide (CBE) which inhibits lysosomal
glycocerebrosidase and leads to the accumulation of glucosylceramide, thus mimicking
Gaucher disease. Decreased levels of glucosylceramide stunt neural growth, while
increased levels caused increased axonal growth and branching.

Figure 1: Glucosylceramide Increases Axon Growth, from Schwartz et al. (1995),
reproduced by permission of the Journal of Biological Chemistry.[see paper for cool illustration of axon growth -- RF]

Dendritogenesis appears to be a necessary step in learning. Associative learning in mice
significantly increases hippocampal dendritic spine density (Leuner et al., 2003), while
enriched environments are also known to increase dendrite density (Holloway, 1966). It
is likely that a tendency to increased dendritogenesis (in Tay-Sachs and Niemann-Pick
heterozygotes) or to increased axonal growth and branching (in Gaucher heterozygotes)
facilitates learning.

Heterozygotes have half the normal amount of the lysosomal hydrolases and should show
modest elevations of the sphingolipid storage compounds. A prediction is that Gaucher,
Tay-Sachs, and Niemann-Pick heterozygotes will have higher tested IQ than control
groups, probably on the order of 5 points.

We do have strong but indirect evidence that one of these, Gaucher disease, does indeed
increase IQ. Professor Ari Zimran, who heads the Gaucher Clinic at the Shaare Zedek
Medical Centre in Jerusalem, furnished us a list of occupations of 302 Gaucher patients.

Because of the Israeli medical care system, these are essentially all the Gaucher patients
in the country. Of the 255 patients who are not retired and not students, 81 are in
occupations that ordinarily average IQ’s greater than 120. There are 13 academics, 23
engineers, 14 scientists, and 31 in other high IQ occupations like accountants, physicians,
or lawyers. The government of Israel states that 1.35% of Israeli’s working age
population are engineers or scientists, while in the Gaucher patient sample 37/255 or 15%
are engineers or scientists. Since Ashkenazim make up 60% of the workforce in Israel, a
conservative base rate for engineers and scientists among Ashkenazim is 2.25% assuming
that all engineers and scientists are Ashkenazim. With this rate, we expect 6 in our
sample and we observe 37. The probability of 37 or more scientists and engineers in our
sample, given a base rate of 2.25%, is approximately 4 x
10-19 . There are 5 physicists in
the sample, while there is an equal number, 5, of unskilled workers. In the United States
the fraction of people with undergraduate or higher degrees in physics is about one in one
thousand. If this fraction applies even approximately to Israel the expected number of
physicists in our sample is 0.25 while we observe 5. Gaucher patients are clearly a very
high IQ subsample of the general population.

Are there Ashkenazi mutations other than these sphingolipid storage disorders that likely
became common because of strong selection for IQ? There are several candidates.

Ever since torsion dystonia among the Ashkenazim was first recognized, observers have
commented on the unusual intelligence of patients. Flatau and Sterling (Eldridge, 1976)
describe their first patient as showing “an intellectual development far exceeding his
age”, and their second patient as showing “extraordinary mental development for his
age.” At least ten other reports in the literature have made similar comments. Eldridge
(1970, 1976) studied 14 Jewish torison dystonia patients: he found that their average IQ
before the onset of symptoms was 121, compared to an averge score of 111 in a control
group of 14 unrelated Jewish children matched for age, sex, and school district. Riklan
and colleagues found that 15 Jewish patients with no family history of dystonia (typical
of DYT1 dystonia) had an average verbal IQ of 117 (Eldridge, 1979; Riklan et al., 1976).

Torsion dystonia is unusual among the Ashkenazi mutations in that it is caused by a lowpenetrance
dominant rather than a recessive, so disease risk and any heterozygote advantage
exist in the same individual. About 10% of heterozygotes have crippling
muscular spasms (usually curable by modern neurosurgery), and such individuals seldom
reproduced in the past. A net fitness advantage could have existed if healthy carriers had
a greater than 10% fitness edge, presumably from increased intelligence. Risch (Risch et
al., 1995) found that linkage data indicate that the DYT1 mutation came into existence
around 300 years ago. He suggests that a high reproductive variance may have decreased
the effective Ashkenazi population size, resulting in drift, but as we pointed earlier, this
proposed mechanism strengthens selection far more than drift. The high gene frequency
and recent origin of the DYT1 are signs of positive selection, while the many
observations of increased intelligence among people with ITD strongly suggests that
increased fitness resulted from increased intelligence.

Non-classic congenital adrenal hyperplasia (CAH) is another mutation that is unusually
common among the Ashkenazim and has been reported to increase IQ. At least seven
studies show high IQ in CAH patients, parents, and siblings, ranging from 107 to 113.
Parents are obligate carriers and 2/3rds of siblings are carriers. There is also SES
elevation in patient families (Nass and Baker, 1991). This mainly applies to the milder
forms of CAH; there is no apparent IQ advantage in seriously ill patients like saltwasters.
The Ashkenazi gene frequency is almost 20% (New and Wilson, 1999).

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In modern times, the Sephardim overwhelmingly resided in the Middle East and North Africa. Some also lived in Europe and the Americas. I didn't know that, but it hardly damages the author's argument, since the Sephardim lived under Islamic conditions during much of the period discussed and most of them continued to until the colonization of Palestine. Hence, Ashkenazi Jews are unquie in the selection pressures to which they are subject.

RS, I have a hard time accepting that a few generations tanning hides or farming would make a whole population dumber on average, anymore than a few generations focusing on money lending or tax collecting will make them generally smarter. His study doesn't really say that exactly, mostly talks about extreme upper end, but seems to infer a good deal more about general populations too. I'm particularly sceptical when so many others Jewish groups were also involved in similar professions as their European brothers and sisters, including "Gentiles". (not an argument line I accept again, but is the authors) Women were for centuries, millenia really, limited in the career choices they could make by social sanctions, based on what proved to be nothing but false and self serving patriarchal beliefs, there were exceptional exceptions but relatively few. Did that make them dumber on average? Old boys thought so, including educated ones, but OC have been consistently proven wrong since. Or was their collective intelligence only maintained by marrying brighter more successful guys? Not very likely either.

It's well known in related scholastic (and Jewish) circles that the Sephardim were of European origin too, Portugal into southern France mostly, they speak (or spoke) a Spanish dialect now called Ladino. I'm not exactly sure why the author makes a point out of questioning their French origins, but that heritage too is fairly well established. It indicates to me a lack of required ethnological knowledge on their parts. Or worse. I can dig something up if you insist though, shouldn't be hard.

ETR>> quote:therefore part of the theory falls apart right there. I will also point out that Jared Diamond himself, to his credit, rejects all the previous attempts to classify "blacks" as dumber on average based on IQ tests. Right before that bit about New Guinea we quibbled over earlier. I can post it if you like.

RSF> That's fine. It would be nice to see you use some evidence to support your assertions. As to the relationship of IQ to intelligence, I refer you to the paper.

Funny, I saw nothing in the paper that demonstrated the many causal links that need to be made to overturn decades of sociological research, not to mention some earlier genetic studies confirming our overwhelming inherent similarities, or the usually slow pace of evolutionary change. Did I miss something due to my ignorance of the hard science? If so please point it out and explain in more detail.

I do tend to make certain statements that I assume are more or less accepted, you're not now disputing Diamond's own example are you? And my point about New Guinea goes right to the heart of this too I believe, you see that too don't you?

ETR>> quote:I can also point out that these conditions mentioned are mostly fatal before adulthood except one, and lo and behold, effect only a small part of the Ashkenazi themselves, even if larger per capita than others, therefore another part of this theory falters. I can post that too.

RSF>: And when and if you do, you will only have established that you don't understand how heterozygote advantage works. Sometimes two copies kill you while one copy helps you.

As for the number affected, that's totally irrelevant to the theory. Besides which, when you add up all these diseases, and consider that there are always many heterozygotes for each homozygote, and the fact that there may be similar intelligence-enhauncing genes without disease-causing side effects, the numbers are plenty big enough to matter.

Why is it "irrelevent" to the study, that IS the topic raised and that was what you keep implying yourself, no? I can, again, post the numbers given, so small that it seems to me highly unlikely to have had any significant impact on the population's average intelligence, certainly not in ways described, unless there's some other genetic factor or linkage I missed? If so, what and how does it work? Any Other "factors" not mentioned or considered here are more "irrelevant" to this paper IMO, as again, the onus is on Them to establish the links. If they have no evidence of such then it's pure speculation not worth considering much further. If they're not bringing forth their whole argument, then they're just being intellectually dishonest.

ETR >> quote:And if this IS unique to that very much mixed population then it tells us next to nothing about human populations in general and is very unlikely candidate for explaining the evolution of common human intelligence to any appreciable extent.

RSF>: This is the kind of statement that just confuses me. Where do they say they are explaining the evolution of human intelligence? They don't. Naturally it's interesting, and there is no reason why sigular exceptions cannot teach us about general principles. It happens all the time in science. For example, identical twins get adopted by seperate families and live independant and ignorant of one anothers' existence. That is a very unusal circumstance, but its been used to learn a lot about genetics and behavoir. In biology it's called a natural experiment.

And, BTW, the authors' point out in several places that the circumstances of the Ashkenazi Jews are probably unquie in human history.

Not a proper analogy when talking about general populations, and IMO that hasn't been established either. I question the data about identical twins or the assumptions made about those few flawed studies, but that's another argument, another day perhaps. Back to the point at hand, have they tested even a significant fraction of the other human groups facing similar environmental and social pressures and isolation, or groups with similar medical conditions that may or may not enhance individual intellegence? Or even surveyed what groups live in environments which may have led to similar theoretical dynamics? That *is* what this is about, or at least getting at, you can't just make one statement then disavow it whenever it's under scrutiny. Look at the heading you gave for example.

ETR>> quote:All it does is open the door to more of this kind of unhealthy speculation.

RSF:> "Unhealthy," huh? Your biases are showing. In fact, it makes testible predictions. So we can do more than speculate; we can test the theory. There's also neurochemistry to be done (some of the beginnings of the investigation are described in the paper) to work out how these genes improve verbal and mathematical skills. So there's a lot of science to be done, as well as the inevitable speculation.

Not a bias, a well established tradition of racist and classist "inquiry" being supported largely by pseudoscience and accepted by other academics because of their own racial prejudices or class interests. A tradition that is historically well established and does carry on more furtively among certain well funded groups, one in which the senior authors just happen to be associated with. That may not make their arguments entirely invalid by itself, but are reasonable grounds for suspicion, as for example Velikovsky's wild theories put his other more modest observations in doubt. I don't even bother looking at that stuff anymore, in fact.

I do not consider the Economist a very objective source either, but to be fair they took a fairly neutral wait-and-see stance on it too. I do know that journalists consistently simplify and too often falsify what's said about such things. Did the same with the socalled "selfish gene" for instance. Cambridge Journal I can't say, was it actually peer reviewed, do they ever print sensationalistic stuff? I have no idea.

Personally, I basically just think the whole thing smells of rightwing classist assumptions, with hints of standard issue MidWestern racism. I'd love to see someone do a "population" study on why blacks may actually be more "intelligent" than whites on average, just for once. I bet that argument could just as easily be made. And dismissed.

ETR>> quote:Sociology can tell us alot about these kind of things too, for example, that most of the genetic mixing between Jews and other Germans, Litvaks, Russians and Poles (some "Ashkenazi" coming from other small groups too, like the Lithuanian "Karaites") would have gone into the Jewish population, not the other way around as the authors speculate, and therefore would have had more effect on "dilluting" their eventual results, as I said earlier. That's actually quite well established historically, women of the weaker ethnic group will be the ones being raped regularly, and these women will be the ones having to decide whether to raise the potential results. Most the "fathers" will just move on in their ignorance. See why I'm sceptical?

RSF>: And the paper explains that genetic inflow is less than 0.5% per generation according to established genetic markers, and that level is consistant with the poisted genetic changes. You get what I'm saying? We don't need to speculate about Cossacks and cuckolds when we can actually sample the gene pool and infer the level of inflow.

Erik, you seem like a really bright guy, and so I implore you, man to man; take an hour; read the paper. It's really interesting reading and it makes the arguments much better than I can at second hand. It may not change your mind, but I'm sure it will change (and improve) your criticism.

Thanks, but I did read it, though did skim over parts, and it didn't look like it was demonstrating much of anything except a lot of assumptions linked together, based on bare plausibilities. But then I'm not a scientist either, so I can only focus on the obvious inadequacies of its theoretical models and the assumptions derived and expanded on. If that seems presumptious on my part, well maybe it is, but then I also feel free to criticise doctors or lawyers too, on certain non-technical grounds, if they seem to be blowing smoke to cover some hidden agenda or expensive mistake. I would never attempt to self diagnose or represent myself in court, but I might still fire a professional who acts unreliable.

Anyhow, I don't know what the study really proves regarding the rate of gene flow or whether the numbers cited are really accurate, or how accurate these measures are compared to the usual ethnic rate of gene flow, if that half a percent is even Low for most identifiable populations, or even if this in itself actually upsets or supports the whole argument or not, but I will say again that most of the genetic flow would have likely been inward not out, as pogroms and rapine were a historical fact from the Crusades on to modern times and those Are the overwhelming historical patterns, despite what the authors claimed. There has also been cosmopolitan subcultures among wealthier, more educated Jews that likely led to higher rates of intermarriage than other poorer cousins. So again, his one demographic bit of research looks like a completely inadequate sample to base his assumptions about relative wealth and demographics on. His assumptuons about occupations are so weak in fact he had to say that noone with a "ninety IQ" could do it(!!) (other related issues here I'll leave for the moment)

Unlike now, birth control wasn't an option for anyone, and large families among poor people were not at all unusual in the old days (demograghic "concerns" are hardly new among upperclass twits) but then I saw little hard data on the actual death and replacement rates among other less "endowed" Jews, beyond that one obviously inadequate sample.

Oh, and inherited wealth Was a reality among Jewish families too, at least until a sovereign lord decided a pogrom was a good way to avoid his debts, so yet another part of the model is in doubt. I dunno, whole thing looks like building a mountain of conclusions on a molehill of facts. Once again, are the "Ashkenazi" really unique in history, and if so then what can it really tell us about whether "some populations are genetically superior in intelligence"? Probably not much, as you now half admit.

[ 09 July 2005: Message edited by: Erik the Red ]

RSF: In the real world, you do not have an infinite amount of error-free data. You have a limited amount of noisy data. In some part of their argument they use "plausible parameters" in some parts "detailed data are not availible." That in no way refers to the argument as a whole, which is constructed out of a large amount of evidence, some circumstanial, some direct, all pointing in the same direction. All completely normal in a scientific hypothesis.

Actually, the real world question of whether someone is wearing certain coloured pants or not is far more limited question than this, even if it's a kind of blind question. There are only three primary colours, three secondary ones, three shades and a generic mix called brown. Being that he specifically says he IS wearing pants we can infer he's not wearing polka dot boxers and there's no issue raised about subtle shading or colour patterns involved, so really a very limited range of issues....except that it might be hard to verify online.

Which kinda goes to Maestro's perfectly valid question, what if anything is known about the relationship between the "heritability" of intelligence? Certainly "intelligence" or lack thereof must exist to varying degrees (mostly between individuals and effected by wide range of other factors) and most likely a certain amount is inherited from parents to children, most would probably agree with that much. And some of which could theoretically be inferred from other data.

Problem again comes back to how do we reliably, that is scientifically, quantify what is actually a qualitative term linguistically to begin with, an imprecise one which denotes no particular levels or kinds itself, then onto what these purported links can be between family lines and occupational pressures then onto larger related (and unrelated) bloodlines and groups which interrmarry. To Maestro's point, what genetic sequences, areas or hormonal factors or whatever *are* in fact identified and established as reliable indicaters of higher or lower than average human intelligence, and how do or did they come into play physically, what activities did in fact effect them, selectively or otherwise?

From what little I've seen, I'd guess that there seems to be very little of *any* hard data on this in which to base these broad (if vaguely defined) assertions on. There's not even much firm data on ethnic groups through history and prehistory, some of which is still contradictory, not more than a small fraction of them over any real length of time at all. So again, it looks like more self supporting assertions that larger gene pools are effected so readily in such short amounts of time in the first place, the core of the argument to begin with.

[ 10 July 2005: Message edited by: Erik the Red ]

quote:

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Anyhow, I don't know what the study really proves regarding the rate of gene flow or whether the numbers cited are really accurate, or how accurate these measures are compared to the usual ethnic rate of gene flow, if that half a percent is even Low for most identifiable populations, or even if this in itself actually upsets or supports the whole argument or not, but I will say again that most of the genetic flow would have likely been inward not out, as pogroms and rapine were a historical fact from the Crusades on to modern times and those Are the overwhelming historical patterns, despite what the authors claimed.

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quote:

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So again, his one demographic bit of research looks like a completely inadequate sample to base his assumptions about relative wealth and demographics on.

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The authors' cited a lot of demographic data in the form of references to others' work. This is very normal for an academic paper and to be expected given that the authors are not demographers(they cite Weinryb, 1972, and Hundert, 1992, and Clark and Hamilton, 2003).

The same is true of the idea that people with an IQ below 90 can't typical do clerical jobs -- that is not their assertion but the finding of Gottfredson (2003), whom they cite. You can certainally find fault with any of these authors' conclusions, but you should realize several things; the authors of this paper are citing the supporting literature, where you need to look for the rest of the evidence; these are the claims of the authors' cited, not unsupported claims by the authors of this paper; though it may be frustrating if you're not used to it, this is a common method of argument and widely accepted in the sciences. It is comparable to citing a well-known court decision in a brief, rather than the entirity of the legal reasoning which led to the decision.

quote:

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RS, I have a hard time accepting that a few generations tanning hides or farming would make a whole population dumber on average, anymore than a few generations focusing on money lending or tax collecting will make them generally smarter. His study doesn't really say that exactly, mostly talks about extreme upper end, but seems to infer a good deal more about general populations too. I'm particularly sceptical when so many others Jewish groups were also involved in similar professions as their European brothers and sisters, including "Gentiles". (not an argument line I accept again, but is the authors) Women were for centuries, millenia really, limited in the career choices they could make by social sanctions, based on what proved to be nothing but false and self serving patriarchal beliefs, there were exceptional exceptions but relatively few. Did that make them dumber on average? Old boys thought so, including educated ones, but OC have been consistently proven wrong since. Or was their collective intelligence only maintained by marrying brighter more successful guys?

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The answer to all these questions is: without a high degree of reproductive isolation, the strongest selection in the world won't change a thing (or not change it very much.

As the authors explain:

quote:

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Assume that a population experienced selective pressures similar to those posited for the
Ashkenazim, such that the parents of the next generation averaged one half an IQ point
higher than the current average while also experiencing significant gene flow from the
general population. For 10% gene flow and a narrow-sense heritability of 0.7, the
maximum IQ increase over many generations would be 3.2 points. For 20% gene flow,
the maximum increase would be 1.4 points. Clearly, any significant amount of gene flow
greatly inhibits local adaptation. We know, however, that the Ashkenazim experienced
very limited inward gene flow, on the order of 0.5% per generation (Hammer et al.,
2000).

Gene flow also limits the natural increase of locally favorable mutations. In a reproductively
isolated population, a mutation that increases fitness in heterozygotes but is lethal
to homozygotes will eventually (if not lost by chance shortly after its origin) reach an
equilibrium frequency of s/(s+1), when s is the heterozygote selective advantage. But if s
is smaller than m (the fractional gene flow), the mutation will not reach this equilibrium -
in fact, it will on average not increase in frequency at all. This means that in a
reproductively isolated population (m < 1%) subject to strong selection for IQ like the
Ashkenazim, mutations increasing IQ or other locally favored traits could well have
increased to polymorphic frequencies. Naturally, these would be mutations that increase
IQ with costs attached–mutations that produced a ‘free’ increase in IQ, with no associated
costs at all would probably have already occurred and reached fixation in all human
populations.

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So . . . be it women, or a business class, or a village full of moneylenders, selection won't happen unless they marry almost exclusively among themselves which, according to the genetic markers, is exactly what the Ashkenazim did. The isolation doesn't have to be perfect, but it's got to be pretty good.

quote:

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Which kinda goes to Maestro's perfectly valid question, what if anything is known about the relationship between the "heritability" of intelligence? Certainly "intelligence" or lack thereof must exist to varying degrees (mostly between individuals and effected by wide range of other factors) and most likely a certain amount is inherited from parents to children, most would probably agree with that much. And some of which could theoretically be inferred from other data.

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Ya, heritability of intelligence is very well established.

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Problem again comes back to how do we reliably, that is scientifically, quantify what is actually a qualitative term linguistically to begin with, an imprecise one which denotes no particular levels or kinds itself,

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It's pretty easy, actually. As a problem, it's compable to astronomers deciding on the difference between an asteroid and a moon, or between a protostar and a gas giant. We can measure things and compare them to other things without tackling the question (which is philosophical more than it is scientific) what they "really" are.

I have a master's in Literary and Cultural Theory, so when I talk about games with definitions, I know whatof I speak.

quote:

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To Maestro's point, what genetic sequences, areas or hormonal factors or whatever *are* in fact identified and established as reliable indicaters of higher or lower than average human intelligence, and how do or did they come into play physically, what activities did in fact effect them, selectively or otherwise?

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For the time being, we can't do an MRI and determine a person's intelligence, although in principle such a test is not impossible. The best way to estimate intelligence, however defined, is to set cognatitive tests and compare people's performance. Nevertheless, the fact that we cannot measure these mechanisms directly does not mean they don't exist.

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Oh, and inherited wealth Was a reality among Jewish families too, at least until a sovereign lord decided a pogrom was a good way to avoid his debts, so yet another part of the model is in doubt.

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So you think you've cast doubt upon the mountain of studies the authors have cited because (you claim) "inherited wealth Was a reality among Jewish families too, at least until a sovereign lord decided a pogrom was a good way to avoid his debts"? I can't decide which part of that statement expresses more historical ignorance.

Why don't you try following your own advice, and presenting some facts, rather than pompous "deductions" based on laughably simplistic history?

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Once again, are the "Ashkenazi" really unique in history, and if so then what can it really tell us about whether "some populations are genetically superior in intelligence"?

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Read the article and tell me. They identify one other population as a possible canadate for this kind of selection.

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Probably not much, as you now half admit.

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This is a straw man in three parts; you misunderstood what the authors were claiming; I suggested their thesis with more modest than you were representing it to be; you claim I've conceeded your point.

I wondered if there were other conclusions that could be reached by examining Nobel prize winners.

From a National Review article:

quote:

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Still, out of a total of 563 Nobel laureates in the Natural Sciences, Economics and Literature in the period, 1901 - 1995, we find only 19 women or 3.4 per cent. The conclusion that high genius is a male characteristic therefore seems to hold true even if literature is included.

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Should we be looking to see if men have generally higher IQ's than women?

[ 11 July 2005: Message edited by: maestro ]

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Should we be looking to see if men have generally higher IQ's than women?

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Speaking as a man...and I'll even tell you I'm a genius if I think you're drunk ...of course men have higher IQs than women. Whites have higher IQs than minorities too. Look at the tests. How could it be any other way?

Something about SATs in the US...women scored higher than men when the tests first came out. That caused them to change the test...they included more sports questions and tended more to math and sciences.

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For the time being, we can't do an MRI and determine a person's intelligence, although in principle such a test is not impossible.

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For the time being? No, there will never be such a test. "Intelligence" cannot be measured in this fashion. You might be able to measure percentage of active brain tissue, or some such, but you'll never be able to physically measure intelligence -- it is far too encompassing for that.

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The best way to estimate intelligence, however defined, is to set cognatitive tests and compare people's performance.

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No, that's not the best way. It is, sadly, the only way we have and thus we put all this emphasis on standardized testing. Tragically, someone's SAT score defines them.

Edited to add: As mentioned by the previous poster, standardized tests are biased, slanted in favour of the people who society most favours.

I wouldn't use Nobel prizes as a sign of intelligence. In many cases, these are politically motivated awards. Two winners of particular note are Henry Kissinger and Egas Moniz. The former was a war criminal and the latter invented electroshock "treatment."

[ 11 July 2005: Message edited by: EFA ]

The same is true of the idea that people with an IQ below 90 can't typical do clerical jobs -- that is not their assertion but the finding of Gottfredson (2003), whom they cite. You can certainally find fault with any of these authors' conclusions, but you should realize several things; the authors of this paper are citing the supporting literature, where you need to look for the rest of the evidence; these are the claims of the authors' cited, not unsupported claims by the authors of this paper; though it may be frustrating if you're not used to it, this is a common method of argument and widely accepted in the sciences. It is comparable to citing a well-known court decision in a brief, rather than the entirity of the legal reasoning which led to the decision.

Thank you Mr.Science, I'm aware of all that. I'm also not quite interested enough in the purported genetic superiority (and by extension inferiority) of certain races -oops- populations, in intellect, ethics or athletic prowess, to plow through all the cited data and it's supposedly supporting data to verify if he's cherry picking, or if these sources are themselves subject to wide criticism. I do remember him making one direct reference to differing opinions, a criticism of J.Gould's work, but hardly an indepth argument. Mostly the authors look like rightwing quacks to me, looking for more subtle ways to salvage some long discredited beliefs; but that's just My non-professional opinion, based partly on their affiliations and past statements and partly on the many broad assumptions they treat as supporting facts. I clearly said as much earlier.

So you think you've cast doubt upon the mountain of studies the authors have cited because (you claim) "inherited wealth Was a reality among Jewish families too, at least until a sovereign lord decided a pogrom was a good way to avoid his debts"? I can't decide which part of that statement expresses more historical ignorance.

Reading comprehension 101 again. That was just one offhand side-comment (more context please) directed at your earlier statement that if this wealth was inherited widely then this whole selection via meritocracy (in part) theory starts to collapse too. I think most here already know that the European Jewish community was often poorer than Christian members of similar social/professional stratas, and of course pogroms happened for a variety of reasons, but there were often political and base pecuniary reasons behind the masses being whipped up too, and within the Jewish community their relative wealth would have been in large part inherited too, that's from the author's own arguments too. Rich smarties outbred poor dumbies, enough to counter some medical disadvantages, remember?

Why don't you try following your own advice, and presenting some facts, rather than pompous "deductions" based on laughably simplistic history?

Why don't you look more closely in your own mirror? You certainly seem to admire yourself often enough.

quote: Once again, are the "Ashkenazi" really unique in history, and if so then what can it really tell us about whether "some populations are genetically superior in intelligence"?

Read the article and tell me. They identify one other population as a possible canadate for this kind of selection.

I did read it, musta missed that part. Who are the one other possible candidates considered - Gypsies, IceLanders, Sea Bajaws, extinct Tasmanians, some isolated Central African tribe? I'm not bothering to read it over again or even ask if he's basing this on comprehensive reviews of the rather fragmentary ethnological data, or how he drew it together etc etc. I'm now fairly certain it'll just be another pissy dead-end.

quote: probably not much, as you now half admit.

This is a straw man in three parts; you misunderstood what the authors were claiming; I suggested their thesis with more modest than you were representing it to be; you claim I've conceeded your point.

C'mon. I know you're better than that.

If there's any straw men here you're the one responsible for constructing them. You continue to conflate this very narrow (and IMO implausible) paper into something of significance, to explain supposedly different levels of intelligence among "populations", or at least imply as much with few if any qualifying statements -at least until someone calls you on it and then you deny and cry foul. This possible exception to the rule does of course imply that others are therefore "inferior" and surely opens the door to more pointless speculation about the "heritability" of intelligence among different ethnic groups, one of the few features that we humanoids like to claim as our own, the one usually assumed to have assured our otherwise rather slow and feeble species of eventual "reproductive success". (you've also said it has little real survival value, while maintaining a theory that itself largely depends on just that idea, even if only under very unusual circumstances)

Am I exaggerating? You yourself argued tenaciously that Jared Diamond said that New Guineans (whatever That means) are genetically superior, intelligence wise -the title of this whole thread in fact- and basically shrugged off the fact that the authors have, shall we say, some "unusual" ideas about this and other politically charged subjects. So primitives only maintain their mental fitness through murder, while the "civilized" can only maintain it through rare diseases and management ghettos, I don't buy that either.

Onto the next:

quote:Which kinda goes to Maestro's perfectly valid question, what if anything is known about the relationship between the "heritability" of intelligence? Certainly "intelligence" or lack thereof must exist to varying degrees (mostly between individuals and effected by wide range of other factors) and most likely a certain amount is inherited from parents to children, most would probably agree with that much. And some of which could theoretically be inferred from other data.

Ya, heritability of intelligence is very well established.

Not quite. We know that intelligence resides in the brain which evolved into a more sophisticated and powerful instrument under selective pressures -over many millions of years. We know that humans are generally smarter by our standards than apes who are in turn smarter than reptiles etc. We know that some individuals are undoubtably geniuses in their fields and others are undoubtably mentally retarded, due to a variety of factors, sometimes environmental. It's even likely that intellect tends to run in families, as does the equally inexact term stupidity, but there too are bright children raised by slow parents and slow children raised by bright parents. (what most generally consider as such) Recessives? Probably. In some cases. And a dozen Other factors we know of and suspect.

We do *not* know that some "populations" are more intelligent on average than others, however, whatever that word is really meant to mean much beyond IQ tests and laurels. Most the world's never even done an IQ test, including whole tribes. Someone consistently testing at a Hundred and Fifty IQ probably is brighter than someone usually testing at One Hundred even, who in turn is probably brighter than someone who averages 50. The large ranges inbetween are far more hazy and variable though, as is the concept that all forms of intellect can be adequately standardized this way, as some clever people just aint good at puzzles and suchlike while others just have less familiarity with academic formats. As has been already repeated here.

If you do have the evidence necessary to back this controversial claim up though, then its time to do somemore work on it and claim your Nobel prize. Meantime, it still looks like humans evolved pretty much together, eventually adapting themselves to different environments and displacing other pre-human groups (with bare possibility of some mixing with some) then exchanging genes and knowledge on a semi-regular basis since.

quote: problem again comes back to how do we reliably, that is scientifically, quantify what is actually a qualitative term linguistically to begin with, an imprecise one which denotes no particular levels or kinds itself,

It's pretty easy, actually. As a problem, it's compable to astronomers deciding on the difference between an asteroid and a moon, or between a protostar and a gas giant. We can measure things and compare them to other things without tackling the question (which is philosophical more than it is scientific) what they "really" are.

I have a master's in Literary and Cultural Theory, so when I talk about games with definitions, I know whatof I speak.

Good on you. You do seem quite good at drawing generic and vague analogies that may or may not have some relevance to the study of intelligence, rather than tangeable objects and clear concepts which can usually be measured someway or other, even if only indirectly. Youre free to say the same of me, I'm only pointing out the weaknesses, not my job to disprove something that authors can barely even describe.

quote: To Maestro's point, what genetic sequences, areas or hormonal factors or whatever *are* in fact identified and established as reliable indicaters of higher or lower than average human intelligence, and how do or did they come into play physically, what activities did in fact effect them, selectively or otherwise?

For the time being, we can't do an MRI and determine a person's intelligence, although in principle such a test is not impossible. The best way to estimate intelligence, however defined, is to set cognatitive tests and compare people's performance. Nevertheless, the fact that we cannot measure these mechanisms directly does not mean they don't exist.

The subject of the paper is those mechanisms in relationship to the Ashkenazim. We certainally don't know everything about how genetics forms and maintains the brain and the rest of the central nervous system. But it's definitely true that genes affect it for better or for worst. The paper discusses several mechanisms.

What I thought, they don't have much of anything really, no maps charting identifiable genetic differences regarding intelligence among individuals and groups. And its not "definitely" true, it's a hypothesis. At least at our present level of knowledge.

Now, I'll post Diamonds comments about IQ tests and Blacks and boldface to clarify what he implies there, then I'll post the bit(s) that bugged me the most with comments, both of which you failed to address this time. Sooner than later.

[ 11 July 2005: Message edited by: Erik the Red ]

quote:

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Originally posted by rsfarrell:

Gene "inflow" and "outflow" are the same thing. Think about it.

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Oh, and are you saying that American men who impregnated Vietnamese women carried some of those "Eurasian" genes back with them to their own isolated towns? News to me.

[ 11 July 2005: Message edited by: Erik the Red ]

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Oh, and are you saying that American men who impregnated Vietnamese women carried some of those "Eurasian" genes back with them to their own isolated towns? News to me.

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Yeah, I sorta wondered about that myself.

Here are some very good examinations of IQ and it's implications, one of which is a specific examination of "The Bell Curve"

I'll put my favourite first. It's not specifically about IQ - although it examines IQ - it's more of a lesson in statistics.

http://www.abelard.org/statistics.htm

From the paper:

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High measured ‘heritability’ within a group does not imply that average measured differences between groups are due to genetic differences between groups. The average measured differences between groups could be due solely to environmental differences even when measured ‘heritability’ within both groups is very high...

Note also that ‘heritability’ is a statistical calculation, it does not imply inheritance. Calling the calculation ‘heritability’ tends to insert an assumption; doing this is not careful scientific analysis or language...

It is by such rhetorical obfuscation that ‘arguments’ concerning supposed ‘heritable’ differences between groups are promoted, even though a careful interpretation of the words used carry a very different (lack of) meaning.

Such texts must be read with great care. Statistical relationships do not ever imply causation, the most they can do is indicate possible connections.

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A couple more sites:

http://tinyurl.com/d2d2e

http://tinyurl.com/9ey6e

That last paper was written in 2005, so it is right up to date.

One of the things that becomes clear when reading these papers is that there is no standard definition of intelligence.

I read another paper in which they mentioned that humans may have 7 different 'IQ's including a musical one. That interested me because I am a semi-pro musician, and have spent a fair bit of time within music 'circles'.

One of the things I noticed is that musical ability doesn't necessarily translate into any other sphere. Some musicians I meet are very articlate and thoughtful people, others are really dull outside of music.

Yet music itself is one of the defining characteristics of the human race. Every culture in the world has music, and it is produced for no other reason than enjoyment.

What kind of an IQ test doesn't recognize musical ability? None of them do.

How about humour? Again, a major characteristic of humans, with every culture having humour and jokes, yet sense of humour never shows up on IQ tests.

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Thank you Mr.Science, I'm aware of all that. I'm also not quite interested enough in the purported genetic superiority (and by extension inferiority) of certain races -oops- populations, in intellect, ethics or athletic prowess, to plow through all the cited data and it's supposedly supporting data to verify if he's cherry picking, or if these sources are themselves subject to wide criticism.

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I don't have the time for that either, sadly, my only point being that you shouldn't say "the authors' only evidence" as if the other evidence weren't there.

quote:

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Originally posted by Erik the Red:

Oh, and are you saying that American men who impregnated Vietnamese women carried some of those "Eurasian" genes back with them to their own isolated towns? News to me.

[ 11 July 2005: Message edited by: Erik the Red ]

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Absolutely they did, along with their Vietnamese brides. But that's neither here nor there. You've just picked a technical term from genetics that you don't understand and are getting all bent out of shape about it. It's kind of funny.

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What I thought, they don't have much of anything really, no maps charting identifiable genetic differences regarding intelligence among individuals and groups. And its not "definitely" true, it's a hypothesis. At least at our present level of knowledge.

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Maps??? There's lots of good stuff, I don't really know what you want, unless it is just whatever the authors' don't have. Did you read the stuff about the Gaucher's patients? What about the fact that all of these supposedly random mutations tie back into the functioning and development of the CNS? There's a lot of good evidence and ingenious deduction. I don't think you've dealt with it seriously, you just sneer at the evidence from a safe distance.

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Now, I'll post Diamonds comments about IQ tests and Blacks and boldface to clarify what he implies there, then I'll post the bit(s) that bugged me the most with comments, both of which you failed to address this time. Sooner than later.

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One of the things that becomes clear when reading these papers is that there is no standard definition of intelligence.

I read another paper in which they mentioned that humans may have 7 different 'IQ's including a musical one. That interested me because I am a semi-pro musician, and have spent a fair bit of time within music 'circles'.

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One of the things the authors' discuss is that while the verbal and math intelligence of the Ashkenazim are a standard deviation above average, their spatial reasoning skills are at or below average.

As for the use of statistics; read the paper. My knowledge of statistics is rudimentary, but I can tell you that the authors have forgotten more about statistics than you or I will ever know.

[ 12 July 2005: Message edited by: rsfarrell ]

quote:

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If there's any straw men here you're the one responsible for constructing them. You continue to conflate this very narrow (and IMO implausible) paper into something of significance, to explain supposedly different levels of intelligence among "populations", or at least imply as much with few if any qualifying statements -at least until someone calls you on it and then you deny and cry foul.

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RSF:Ya, heritability of intelligence is very well established.

Erik: Not quite. We know that intelligence resides in the brain which evolved into a more sophisticated and powerful instrument under selective pressures -over many millions of years. We know that humans are generally smarter by our standards than apes who are in turn smarter than reptiles etc. We know that some individuals are undoubtably geniuses in their fields and others are undoubtably mentally retarded, due to a variety of factors, sometimes environmental. It's even likely that intellect tends to run in families, as does the equally inexact term stupidity, but there too are bright children raised by slow parents and slow children raised by bright parents. (what most generally consider as such) Recessives? Probably. In some cases. And a dozen Other factors we know of and suspect.

We do *not* know that some "populations" are more intelligent on average than others, however, whatever that word is really meant to mean much beyond IQ tests and laurels.

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Something that passes through families is heritable. It has nothing to do populations. Therefore to say intelligence is heriatable is not to claim anything about any population.

You can't keep simple distinctions like this straight, but you think you know all about genetics, and all about my supposed sweeping claims, which when examined will prove to be the product of more of your sloppy reading and ignorance of the subject.

I am tired of arguing with you. I don't think you have any interest in this research at this point, if you ever did; you just want to "win" the discussion.

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My knowledge of statistics is rudimentary, but I can tell you that the authors have forgotten more about statistics than you or I will ever know.

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quote:

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I really think this research is very cool, very interesting and thought-provoking, and I'd like to talk about it. But I'm beginning to think nobody else does.

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Something that passes through families is heritable. It has nothing to do populations. Therefore to say intelligence is heriatable is not to claim anything about any population.

You can't keep simple distinctions like this straight,

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Actually it's you that can't (and hasn't) kept that simple distinction straight. In fact, I'd say you were the person most responsible for muddying the distinction.

quote:

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Originally posted by maestro:

Actually it's you that can't (and hasn't) kept that simple distinction straight. In fact, I'd say you were the person most responsible for muddying the distinction.

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How about a supporting quote? There isn't one. You are absolutely wrong in ascribing that confusion to me, when I have been patiently undertaking the Herculean task of explaining this basic scientific vocabulary of this paper to people like Erik, and you, who don't understand it and think they know all about it.

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I suggest you read the three papers I posted. It will give you a broader perspective on this issue.

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The papers you posted aren't about this issue; they are about the "bell curve" idea. They all acknowledge that intelligence is partly a function of genetics, and none of them discussion the relationship between Ashkenazi genetic diseases and intelligence.

quote:

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Originally posted by ronb:
[QB]

It seems that nobody else here thinks this research is remotely reputable, let alone "cool and thought-provoking". Gee, I wonder why?

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I could suggest a few reasons.

quote:

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This branch of "science" has such a distinguished pedigree after all.

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Do you mean genetics, or cultural anthropology? Never mind, I know what you mean; you think it presents a threat to your ideological premises (which it doesn't, really) and so you're too scared to take a look at it. I understand.

quote:

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Originally posted by maestro:

How do you know that?

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quote:

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I've been trying to goad you into addressing my own arguments more directly with a few rather broad statements of my own (most of which I can back up if we ever got to that) but apparently in vain.

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About the point at which someone admits that they're trying to "goad" me with "rather broad" statement that he can "mostly" back up, is the point where I cease to be interested in continuing the conversation.

[ 12 July 2005: Message edited by: rsfarrell ]

quote:

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Originally posted by rsfarrell:
Read the paper.

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And far be it from me to interrupt as you scramble to sanction and find an academic basis for racism/discrimination, but I can tell you right now that it's not the authors' grasp of statistics that makes the article convincing to people like you. As someone who knows a thing or two about statistics, I submit that the authors don't even have a solid grasp on basic math. It's the way the story is told that makes it effective. It's sort of a death by a thousand paper cuts sort of approach. You bombard the reader with as many factoids-- however poorly substantiated-- as you can with the hope that people will just eventually give up thinking critically and accept your thesis. Fret not, however: for many readers, these factoids need not even be related to the topic at hand. Just throw out a bunch of different observations/ speculations and people's eyes begin to glass over. Get it? The factoids are the paper cuts and the death is critical thinking.

If this were a court case, we would say that all of the evidence presented was circumstantial and hearsay. No physical evidence. No motive. All kinds of reasonable doubt.

The only thing that they have sorta kinda established here is that one population seems to have a higher average IQ than the population at large. That's it. Using exactly the same reasoning, you could take a population of Amish folks and conclude that they are genetically pre-disposed to work hard and to eschew technology (oh, and to wear those adorable hats!). This is a case of illusory correlation.

If they wanted to prove their thesis, they'd have to do a bunch of things. First of all, as jeff house pointed out, they have to establish some sort of selective pressure that is exerted as a result of lower intelligence. But they didn't. They didn't even really try, except to speculate that they think more affluent families had more children. But they had no proof. This is a key point, because, without selective pressure, the ENTIRE paper is a waste of time. Then they'd have to provide a direct link between the various genetic mutations and intelligence. They need to measure the intelligence of a sample and compare the intelligence of each individual with their individual IQ results. But even that wouldn't be enough. On top of that, they need to round up a bunch of individuals who left the population and see if the IQ effect (if any) withstands people leaving a learning-friendly environment. Either that, or they'd have to search for the same mutations in the population at large and determine if this provides some sort of robust IQ endowment. Which it won't. But they'd still have to do it to make a serious argument. But they won't.

Amish people, for example, suffer from many genetic abnormalities due to inbreeding and not due to evolving into harder-working creatures. Nonetheless, these authors could employ their exact same methods and conclude that the Amish and genetically superior in their work ethic. The reality is that the Amish folks become pretty much like all other European immigrants once they leave their compounds.

I could go through the paper exhaustively, showing all its many flaws, but I won't; the posters before me have shredded it pretty well already. People who want to believe this paper's claims will do so, despite all evidence to the contrary. People endowed with critical thinking skills will realize that it doesn't meet even a basic sniff test.

[ 12 July 2005: Message edited by: Dex ]

quote:

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Read the paper.

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Have read the paper...looks to me like they made the same mistake you made - not distinguishing the difference between heritability statistics and group statistics.

As far as the papers I posted not being relevant, to quote yourself, that's nonsense.

Every one of them speaks directly to the heritablility of IQ, and the problems therewith (by the way, there's a lot more out there that say more or less the same thing as the ones I posted).

The one on statistics speaks directly to the misunderstanding of heritability.

They also speak directly to the fact that 'intelligence' is a human construct, not a natural one.

It is one of the assumptions of various IQ 'authorities' that intelligence is that which is measured by intelligence tests. That is an utterly arbitrary definition.

You seem to have somehow latched onto the Cochran, Harpending, Hardy paper as some grand bit of research that only you can understand, and the rest of the world can't.

You rationalize away their lack of citations for a central part of their hypothesis, telling us peasants that that is just the way scientists work and that's how they write their papers.

If you had read the citations, you would have discovered they were very shaky propostions themselves. That bit about the census of Brody in 1764 is a prime example of how shaky the evidence is.

So is the evidence offered by Clarke and Hamilton re: the demographic transition. There may indeed have been a demographic transition (which I don't necessarily accept), but that doesn't speak to the effect on individual families, and their ability to 'pass on the genes'.

Here's a question for you, how many wealthy families of two hundred years ago are still wealthy today?

What does than mean in terms of those families being able to pass along the genetic wherewithal to maintain their wealth?

Here's another question. Given two families of equal wealth, will a family with two children be more able to provide for their children than the family with ten children?

The answer is obvious, yet it points directly to families being less able to protect their wealth the more children they have (certainly in the days before the 'public' company).

Thus, those families that were better at reproducing their genes would perforce be more limited in their ability to maintain the wherewithal to continue to do so.

This relatively simple and obvious fact seems to have escaped the study's authors.

Here's a comment from someone who knows, although they were speaking to the immigration issue, their comments are worth absorbing:

quote:

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Lies about Heritability - II
The second falsehood about heritability that is perpetuated by racist cranks who like to fulminate about the evils of immigration is that if a given trait has a very high heritability figure, any efforts to change it must necessarily be doomed to failure; in fact nothing of the sort is true.

To see what I'm getting at, consider the following hypothetical example: we have five families, A, B, C, D and E, amongst whom the heritability of IQ is 1.0, i.e, 100%.

This heritability figure is far out of the bounds of possibility, but for that very reason it suits my argument perfectly.

Anyway, let us assume that families A through E are situated in rural Farkistan, all sharing the exact same environment, and that the IQs of their members are assessed at A=65, B=70, C=75, D=80, and E=85.

Let us now suppose that families A through E now immigrate to the Nordic kingdom of Blisstonia, where universal access to uniformly high-quality education and healthcare can be taken for granted; what would one expect to happen to the IQs of the next generation?

If one were to buy into the idiotic reasoning of the anti-immigration shitheads, one would assume that since heritability is 1.0, the IQs of the immigrant families' children would still range from 65 to 85, when in fact it could actually transpire that the real IQ numbers are A=105, B=110, C=115, D=120, and E=125, perfectly in keeping with the complete heritability of IQ!

In plain English, heritability in itself says nothing about the degree to which a change in circumstances can lead to changes in the value of a trait, a fact which is seen easily enough when one considers that height is one physical trait with extremely high heritability under most circumstances, and yet one which is well known to respond dramatically to changes in childhood nutritional intake.

It is the mark of the uninformed charlatan to sigh and point out the supposed high value of IQ heritability as evidence that Mexicans and Guatemalans are forever doomed to be hewers of wood and drawers of water (or the Ashkenazi's doomed to be winners of Nobel prizes) because of their innate genetic limitations -

- it is bad enough that one is illegitimately taking heritability estimates for white, English-speaking, middle-class Americans and blithely applying them to vastly different populations, but to then claim that it implies that they're doomed to lives of stupidity is a dead giveaway that one doesn't have the slightest clue about what one is talking about.

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quote:

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Originally posted by Dex:
See, I have.

And far be it from me to interrupt as you scramble to sanction and find an academic basis for racism/discrimination,

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And from the first sentence, you reveal that, while you have better rhetorical skills that most of your fellows, you still have the same misunderstanding of what the paper is about and what, if true, it would mean.

quote:

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but I can tell you right now that it's not the authors' grasp of statistics that makes the article convincing to people like you.

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"People like you." Of course, if you don't have any rational objections, you can always go straight for the ad hominems.

quote:

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As someone who knows a thing or two about statistics, I submit that the authors don't even have a solid grasp on basic math.

---

Funny that the NYT and the Economist didn't notice that, or spoke to anyone who did, despite the probably that before publishing anything as explosive as this research they talk to more than one scientist not involved in the research.

Of course, you don't cite any examples of this supposed lack of math skills, because there isn't any.

quote:

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It's the way the story is told that makes it effective. It's sort of a death by a thousand paper cuts sort of approach.

---

In some circles that's called collecting and presenting evidence. Perhaps they should write more like you, in a smooth stream of fallacies and unsupported assertions unbroken by supporting facts?

quote:

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You bombard the reader with as many factoids-- however poorly substantiated-- as you can with the hope that people will just eventually give up thinking critically and accept your thesis. Fret not, however: for many readers, these factoids need not even be related to the topic at hand. Just throw out a bunch of different observations/ speculations and people's eyes begin to glass over. Get it? The factoids are the paper cuts and the death is critical thinking.

---

Substitute the phrase "unsupported assertions" for "factoids" and you have a good description for how you are trying to undermine the argument, but it has nothing to do with the argument, which all hangs together very well.

quote:

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If this were a court case, we would say that all of the evidence presented was circumstantial and hearsay. No physical evidence. No motive. All kinds of reasonable doubt.

---

That's quite true. But as I said above, it's not a court case, but more of a motion hearing; you can directly test the author's hypothesis by running intelligence tests on people heterozygous for some of these genetic diseases. They should do about five points better. But you don't do a study like that until someone, the authors for example, has given you a reason to. So, to continue the analogy, it's more of a motion hearing rather than a trial; the standard is more like probable cause, not beyond a reasonable doubt.

quote:

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The only thing that they have sorta kinda established here is that one population seems to have a higher average IQ than the population at large. That's it.

---

Wrong. They've also established that people with several kinds of genetic disorders seem to be smarter than people without them. They've raised substansive doubts about the ability of the bottleneck hypothesis or the founder effect to explain this cluster of genetic diseases among the Ashkenazim. They've outlined a possible mechanism by which these genes could be enhauncing intelligence. And so on.

quote:

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Using exactly the same reasoning, you could take a population of Amish folks and conclude that they are genetically pre-disposed to work hard and to eschew technology (oh, and to wear those adorable hats!). This is a case of illusory correlation.

---

Nope, it's not. For one thing, there is no evidence that Amish people with those diseases are more inclined to work hard of eschew technology. Nor do the Amish genetic diseases deny the pattern of the founder effect in the way Ashkenazi diseases do. And so on. You're not doing justice to the argument, rather you are oversimplifying it and seeking up a straw man.

quote:

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If they wanted to prove their thesis, they'd have to do a bunch of things. First of all, as jeff house pointed out, they have to establish some sort of selective pressure that is exerted as a result of lower intelligence. But they didn't.

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Sure they did, and supported it with numerous sources. See above.

quote:

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Then they'd have to provide a direct link between the various genetic mutations and intelligence.

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Which they did, see above.

quote:

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They need to measure the intelligence of a sample and compare the intelligence of each individual with their individual IQ results. But even that wouldn't be enough. On top of that, they need to round up a bunch of individuals who left the population and see if the IQ effect (if any) withstands people leaving a learning-friendly environment. Either that, or they'd have to search for the same mutations in the population at large and determine if this provides some sort of robust IQ endowment. Which it won't.

---

Oh, you've decided it won't, huh? And if it does, you'll decide they need something else, and something else, meanwhile ignoring the evidence that some of these diseases do, in fact, make people a little smarter.

quote:

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Amish people, for example, suffer from many genetic abnormalities due to inbreeding and not due to evolving into harder-working creatures. Nonetheless, these authors could employ their exact same methods and conclude that the Amish and genetically superior in their work ethic.

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As you said above, and you're still wrong, for the same reasons.

quote:

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I could go through the paper exhaustively, showing all its many flaws, but I won't; the posters before me have shredded it pretty well already.

---

quote:

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People who want to believe this paper's claims will do so, despite all evidence to the contrary. People endowed with critical thinking skills will realize that it doesn't meet even a basic sniff test.

---

quote:

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Oh, you've decided it won't, huh? And if it does, you'll decide they need something else, and something else, meanwhile ignoring the evidence that some of these diseases do, in fact, make people a little smarter.

---

quote:

---

Originally posted by EFA:

Don't want to wade into this debate, nor do I want to read the article in question, but could somebody please explain how a genetic disease could "make" someone smarter?

---

Good question; there are a number of ways, but here's one as the authors explain it:

quote:

---

. . . [T]he sphingolipid mutations look like IQ boosters. The key datum is the effect of increased levels of the storage compounds.
Glucosylceramide, the Gaucher storage compound,
promotes axonal growth and branching (Schwartz et al., 1995). In vitro, decreased
glucosylceramide results in stunted neurons with short axons while an increase over
normal levels (caused by chemically inhibiting glucocerebrosidase) increases axon length
and branching. There is a similar effect in Tay-Sachs (Walkley et al., 2000; Walkley,
2003): decreased levels of GM2 ganglioside inhibit dendrite growth, while an increase
over normal levels causes a marked increase in dendritogenesis. This increased
dendritogenesis also occurs in Niemann-Pick type A cells, and in animal models of Tay-
Sachs and Niemann-Pick.

Figure 1, from Schwartz et al. (1995) shows the effect of glucosylceramide, the sphingolipid
that accumulates in Gaucher disease. These camera lucida drawings of cultured
rat hippocampal neurons show the effect of fumonisin, which inhibits glucosylceramide
synthesis, and of conduritol B-epoxide (CBE) which inhibits lysosomal
glycocerebrosidase and leads to the accumulation of glucosylceramide, thus mimicking
Gaucher disease. Decreased levels of glucosylceramide stunt neural growth, while
increased levels caused increased axonal growth and branching.

Figure 1: Glucosylceramide Increases Axon Growth, from Schwartz et al. (1995),
reproduced by permission of the Journal of Biological Chemistry.[see paper for cool illustration of axon growth -- RF]

Dendritogenesis appears to be a necessary step in learning. Associative learning in mice
significantly increases hippocampal dendritic spine density (Leuner et al., 2003), while
enriched environments are also known to increase dendrite density (Holloway, 1966). It
is likely that a tendency to increased dendritogenesis (in Tay-Sachs and Niemann-Pick
heterozygotes) or to increased axonal growth and branching (in Gaucher heterozygotes)
facilitates learning.

Heterozygotes have half the normal amount of the lysosomal hydrolases and should show
modest elevations of the sphingolipid storage compounds. A prediction is that Gaucher,
Tay-Sachs, and Niemann-Pick heterozygotes will have higher tested IQ than control
groups, probably on the order of 5 points.

---

So . . . these mutations cause diseases when you have two copies (which the authors' think are really side effects, essentially). One copy --} elevated levels of storage compounds --} more dendritogenesis, which is is known to be assoiciated with learning --} the people with one copy of the gene are a little smarter than average.

quote:

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So . . . these mutations cause diseases when you have two copies (which the authors' think are really side effects, essentially). One copy --} elevated levels of storage compounds --} more dendritogenesis, which is is known to be assoiciated with learning --} the people with one copy of the gene are a little smarter than average.

There are other disorders and other possible mechanisms, but that's one example. Wild, huh?

---

Thanks for taking the time to pull that out. A few things jump out at me:

(1) This sounds somewhat parallel to some stuff in a genetics course I took during my animal science days at UBC. It's in the best interests of a disease to have its coding carried by a recessive gene. I can't explain it very well because I don't remember the correct terms but basically being recessive allows the faulty gene to continue through the population. If it were dominant, every time two adults that both had the gene produced a child, that child would have the disease, possibly a fatal one. I was under the impression that most serious genetic illnesses were carried on recessive genes.

(2) I am really troubled that IQ testing is given as much credence as it is. All kinds of studies have shown IQ testing to be horribly biased in favour of the cultural majority. I've had my IQ tested and I agree with these studies. Further, even if that cultural bias were somehow removed, IQ testing is still a very ineffective way to measure intelligence. I have the same issue with the LSAT. It measures a few very specific skills but says nothing, over all, about somebody's aptitude for lawyering. I realize that both IQ testing and the LSAT are considered necessary conveniences but, even so, I think we'd almost be better off without information than with crappy information.

Instead, I thought it would be more fun to take points that you seemed to think were especially airtight and take them apart. I'll tell you what: I'll take the one to which you keep returning first and then you can just name each of what you feel are the most compelling parts of the paper and I'll give you a straightforward scientific or statistical reason why it doesn't back up their thesis.

So. On multiple occasions on this thread, you've touted the statistical, um, prowess of the paper's authors. Here's but one example of the questionable skills presented therein:

quote:

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"During the 20th century, [Ashkenazi Jews] made up about 3% of the US population but won 27% of the US Nobel science prizes and 25% of the ACM Turing awards. They account for more than half of world chess champions.

While the mean IQ difference between Ashkenazim and other northern Europeans may not seem large, such a small difference maps to a large difference in the proportion of the population with very high IQs (Crow, 2002). For example if the mean Ashkenazi IQ is 110 and the standard deviation is 15, then the number of northern Europeans with IQs
greater than 140 should be 4 per thousand while 23 per thousand Ashkenazim should exceed the same threshold, a six fold difference."

---

This brief passage brings up two very important issues of causality. One is the notion that Ashkenazi folks inherit intelligence. The authors don't prove that at all at any point in the paper. In order to exclude the possibility that it's simply the social environment that leads to higher intelligence, they'd have to track Ashkenazi folks who had, say, been adopted outside by non-Ashkenazi folks. If an Ashkenazi infant went to a trailer park in Appalachia and still turned out to be super smart, then you would have some convincing evidence. On top of that, they'd also have to have examples of non-Ashkenazi folks growing up and living among the Ashkenazi folks to verify that these new members of the population perform worse on IQ tests.

The second notion is that a high IQ necessarily leads to Nobel prizes and such. The allusion is that an IQ>140 makes you a lock for a Nobel. They don't say that, of course, because why would you ever speak clearly and carefully when trying to build a scientific basis for racism and discrimination. You need to be smart to win a Nobel, for sure, but is it the extra one or two points that may or may not be attributed to Ashkenazim intelligence that puts them over the top or is it something else? I know what you and the authors think, but I also know that they have no proof.

Of course, I suspect that you will be tempted to sweep aside the foregoing as having nothing to do with statistics, and that's certainly your right. It would be wrong, but it's certainly your right. But here's where the wheels really start to fall off.

The authors fire out the fact that 23 per 1000 Ashzenazim will have an IQ >140 compared to 4 per 1000 of the population at large. If we take off our shoes and socks and do a little counting, something weird emerges: given that Ashkenzim folks make up 3% of the population and thus there are 33.3 times more non-Ashkenasi folks, we should still expect 33.3 x 4 = 133.2, 133.2 / 23 = ~5.8 times as many non-Ashkenazi folks to have an IQ better than 140. Keep in mind that we still have no proof that IQ >140 lead to a Nobel prize. But, even if it does, how do the authors explain the fact that Ashkenazi folks had such a strangle hold on the Nobels? Could it be that there was something institutional going on? Could it be that the Ashkenazi folks were encouraged to undertake scientific research? Could it be that they came from families of influence who helped them by securing prime positions and/or funding for their research? Something isn't adding up here. Not surprisingly, the authors pay no heed to this.

They offer up another useless stat, pointing out that Ashkenazis supplied more than half of the world's chess champions. Ignoring the fact that they provide no proof of the association between chess prowess and IQ, there are still more questions. Relative to the population as a whole, how big a part does chess play in Ashkenazi life? So, um, are [white] Canadians genetically predisposed to dominate hockey? Are most black people unable to play hockey at a high level? Or is it that systemic racism and a lack of role models causes black kids to shy away from the sport? Or, even more shockingly, are black kids just as good and equally represented in hockey? Or is it because the best Canadian athletes tend to be shunted into hockey, as they are shunted into rugby in Australia and cricket in India, and soccer in Brazil. See, we're never going to know with papers like this because they can't even be bothered to ask these crucial questions as it would totally undermine their thesis.

This just in: Americans are genetically predisposed to driving large vehicles. Canadians are genetically predisposed to wearing parkas, but only in months containing the letter R. Germans are genetically superior in their ability to speak German. Babble users are genetically predisposed to type the letters B-W-A-G-A in succession.

The biggest problem with this whole line of research is that it assumes that race is much more than a lazy and damaging set of bins created by humans in which to sort those who are different from them. Sickle cell anemia is labeled by most as a 'black' disease, but it's not. It's a disease that is prevalent in areas with high levels of malaria. There are plenty of non-black populations that also have a high incidence of sickle cell alleles. It's simply the fact that a lot of the slaves brought over here happen to have dark skin and were from malaria-infested areas. It's only with our pathetic categorizing fervour that we've been able to strongly associate it as a black thing as opposed to a malarial thing.

[ 13 July 2005: Message edited by: Dex ]

EFA wrote:

quote:

---

I have the same issue with the LSAT. It measures a few very specific skills but says nothing, over all, about somebody's aptitude for lawyering.

---

I have the same issue with law school and bar ad testing. Specifically, the income tax course is (or at least, was for many decades) required. So
too was a Bar Ad course/exam on tax.

quote:

---

Originally posted by RP.:
Who really fails the bar exam though?

---

I thought John Kennedy Jr. failed this several times. But I agree that most people who get through law school pass the bar exam, whereas lots of people who could sail through law school fail the LSAT.

Edited to add: The LSAT doesn't concern me much, as my score was acceptable for getting in on the Gimp Ticket, as we say in politically incorrect world.

[ 13 July 2005: Message edited by: EFA ]

**************************************************

Re: LSAT and IQ, etc. Look, in all fairness, these metrics actually do a reasonable job at predicting success in things like graduate school and even some occupations. There is actually credible evidence of that. Unfortunately for the authors, however, owning a BMW versus owning a Chevy (or in the olden days upon which we are speculating, traveling on a single saddled horse versus in an opulent carriage pulled by a team of white steeds) doesn't create a whole lot of selective pressure as far as genes go. The authors offer no evidence that lack of smarts lead to significantly higher rates of death. Their whole logic for natural selection pressures resides in their feeble claim that more 'successful' families seem to have had more children. That's it. They also willfully ignore the possibility that things like nepotism and non-smarts-required (e.g., tradesmen, shop keepers, clergy) positions could have wiped out any gains that the 'smart' people may have been able to make.

The most controversial and odious thrust of this paper is the attempt to arbitrarily tie it to ethnic background. Instead of adopting a thesis that Tay Sachs alleles will impart higher intelligence to carriers, the authors choose to ignore the fact that many Ashkenazi folks don't carry those alleles. And, more importantly, lots of non-Ashkenazi folks do carry those alleles. Why not compare Ashkenazi Tay Sachs folks with Ashkenazi non-Tay Sachs folks? Why not compare Ashkenazi Tay Sachs folks with non-Ashkenazi Tay Sachs folks? That there is almost no admission of these crucial tests speaks volumes. The reason, I sadly submit, is the authors' obsession with showing one arbitrarily defined ethnic group to be superior to another.

[ 13 July 2005: Message edited by: Dex ]

quote:

---

Originally posted by jeff house:
In my year, a young woman committed suicide the day after she failed.

---

It breaks my heart when people, especially young people, fail to understand the true meaning of success. This sounds like a young woman who didn't even begin to understand.

quote:

---

Re: LSAT and IQ, etc. Look, in all fairness, these metrics actually do a reasonable job at predicting success in things like graduate school and even some occupations. There is actually credible evidence of that.

---

I really don't think they do. I would agree, however, that for the LSAT there is a significant group of people who will do well on the test, in law school and in their legal career.

However, I've written the test and I can tell you the things they're testing for are only a tiny, tiny, tiny part of what's required to be a successful legal advocate.

quote:

---

Re: LSAT and IQ, etc. Look, in all fairness, these metrics actually do a reasonable job at predicting success in things like graduate school and even some occupations. There is actually credible evidence of that.

---

Yes, there is. Which is the answer to the many people who have been claiming that IQ doesn't mean anything.

quote:

---

Unfortunately for the authors, however, owning a BMW versus owning a Chevy (or in the olden days upon which we are speculating, traveling on a single saddled horse versus in an opulent carriage pulled by a team of white steeds) doesn't create a whole lot of selective pressure as far as genes go.

---

That's where you're wrong. In the days before the modern welfare state, money did indeed often make the difference between life and death. Who could afford a doctor when they were sick? Who could afford plenty of healthy food? Who could afford to get out of town when sickness swept through? Who could afford to educate large families? And the demographic data support that model, which is typical of pre-modern societies.

quote:

---

That's it. They also willfully ignore the possibility that things like nepotism and non-smarts-required (e.g., tradesmen, shop keepers, clergy) positions could have wiped out any gains that the 'smart' people may have been able to make.

---

"Willfully ignore," huh? Actually, they do analyze that possibility in some detail. Read the paper.

quote:

---

The most controversial and odious thrust of this paper is the attempt to arbitrarily tie it to ethnic background.

---

Again, you show that at bottom, you just don't understand what the authors are claiming. The selection pressures operated on a reproductively isolated population. It is hardly even an ethnic group, given that censues-takers hardly distinguish between Ashkenazi and Sephadrim. If you said "Ashkenazi" to the average person, the response would probably be "bless you."

quote:

---

Instead of adopting a thesis that Tay Sachs alleles will impart higher intelligence to carriers, the authors choose to ignore the fact that many Ashkenazi folks don't carry those alleles.

---

They do say that Tay-Sachs alleles will impart higher intelligence to carriers! Nowhere is it said or suggested that the effect only happens in Ashkenazi Jews. I can't believe the amount of time I'm wasting on people who haven't read or haven't understood the paper. These alleles work the same in everybody. Ashkenazi Jews have a very high concentration of a whole bunch of different intelligence-enhauncing alleles, and the question is, why.

quote:

---

And, more importantly, lots of non-Ashkenazi folks do carry those alleles. Why not compare Ashkenazi Tay Sachs folks with Ashkenazi non-Tay Sachs folks?

---

quote:

---

Which is the answer to the many people who have been claiming that IQ doesn't mean anything.

---

That's not our argument. Our argument is that IQ is not an accurate measurement of intelligence.

Edited to add: Like the LSAT, it's a test which measures testing aptitude.

[ 13 July 2005: Message edited by: EFA ]

quote:

---

Originally posted by Dex:
btw, the incidence of Tay Sachs disease in French Canadians (1 in 40) is very similar to that of Ashkenazi Jews (1 in 26, compared with ~1 in 300 in the general population). I wonder why so few French Canadians won Nobel prizes or chess championships? Oops, that's right: ignore inconvenient facts that run counter to your thesis. I forgot. Sorry.

---

BTW, Tay-Saches is one of over a dozen different mutations which affect the Ashkenazim in high concentrations. Tay-Saches is not the whole story by any means, and thus the comparison is faulty. (And they did have Philidor).

quote:

---

The biggest problem with this whole line of research is that it assumes that race is much more than a lazy and damaging set of bins created by humans in which to sort those who are different from them.

---

No, the biggest problem with your criticism is that you are determined to see the bogeyman of race where is doesn't exist. This is a population, not a race. They mated in large part with each other. They were subject to similar persecution. The combination of the two may have cause intelligence-enhauncing mutations to appear more frequently inside that population than outside. That's it.

quote:

---

Sickle cell anemia is labeled by most as a 'black' disease, but it's not. It's a disease that is prevalent in areas with high levels of malaria. There are plenty of non-black populations that also have a high incidence of sickle cell alleles. It's simply the fact that a lot of the slaves brought over here happen to have dark skin and were from malaria-infested areas. It's only with our pathetic categorizing fervour that we've been able to strongly associate it as a black thing as opposed to a malarial thing.

---

As to how junk science ends up being reported in the NYT and WSJ - on the science beat, if it sounds neat and/or contoversial and likely to sell papers, they'll report it. If it turns out to be a pile of poo, they'll report that too. Just because it was reported in the papers doesn't automatically make it true. Didn't your mom teach you that?

I have no reason to doubt that you read the paper. However, I have serious doubts about the comprehension side of things. From the very title of the paper ("Natural History of Ashkenazi Intelligence"), all the way down through the final conclusion ("high IQ test scores of Ashkenazim, along with their unusual pattern of abilities"; "pattern of high achievement among Ashkenazi Jews and the observed psychometric results"), the authors obsess about Ashkenazi Judaism to the exlusion of all other populations and possible alternate explanations. If they weren't so obsessed with ethnicity, they would have couched the paper in terms of sphingolipid mutations, IQ, and natural selection. Instead, though, at every turn, they go to painstaking lengths to differentiate Ashkenazi Jews from all other populations, often going well outside the scope of the paper and offering anecdotal, unsubstantiated, irrelevant claims in order to pursue their cause.

quote:

---

Originally posted by Dex:
[QB]rsfarrell,
I was thinking about this last night, what I could do to convince you of the shortcomings of this paper. I thought about letting you pick any page of your choice from the paper and then I could write several pages about how that single page was faulty in various and sundry ways. Part of what I do for a living is review papers in the social sciences, but I don't really have the time to write dozens of pages of rebuttal against something that clearly is not worth my time. I am a little ashamed to admit, though, that I do sort of enjoy seeing you flounder about in this thread, especially when it is put into the context of your other posts here at rabble.

---

You know, for all your silly trash talk, I rather enjoy your posts, because you know a little about genetics, and it makes you so much easier to refute.

quote:

---

Instead, I thought it would be more fun to take points that you seemed to think were especially airtight and take them apart.

---

You seem to enjoy this sort of macho me-against-you verbage, but there is no me and you. You have yet to raise any serious criticism of the article. Mostly, the more you talk about it the more clear it becomes that you don't understand it, as is the case below.

quote:

---

So. On multiple occasions on this thread, you've touted the statistical, um, prowess of the paper's authors. Here's but one example of the questionable skills presented therein: Where to start, where to start.

---

It strikes me that if you were really all that confident in your analytical abilities, you'd get down to it, instead of jawing and jawing.

quote:

---

Ok. One of the first rules in statistics is that correlation does not equal causation.

---

Yep. Correlation is important, nevertheless. When two things are correlated, one of several things is happening; A & B are correlated by random chance; A causes B; B causes A; or both A and B are caused by C.

quote:

---

This brief passage brings up two very important issues of causality. One is the notion that Ashkenazi folks inherit intelligence.

---

Everyone inherits intelligence. Do you mean something different?

quote:

---

The authors don't prove that at all at any point in the paper. In order to exclude the possibility that it's simply the social environment that leads to higher intelligence, they'd have to track Ashkenazi folks who had, say, been adopted outside by non-Ashkenazi folks. If an Ashkenazi infant went to a trailer park in Appalachia and still turned out to be super smart, then you would have some convincing evidence. On top of that, they'd also have to have examples of non-Ashkenazi folks growing up and living among the Ashkenazi folks to verify that these new members of the population perform worse on IQ tests.

---

As the authors argue:

quote:

---

Some would suggest that, even though IQ scores are heritable, there are no biological
differences in mean IQ between populations and that the well-known differences among
ethnic groups in North America are the result of racism or deprivation or some other
social cause. Similarly one might argue that high Ashkenazi scores are the result of home
environments that encourage scholarship. There is scarcely any support in the literature
for social effects like home environment on IQ (Rowe, 1993). A standard textbook on IQ,
after reviewing environmental effects, concludes that “. . . , it is all too easy to throw up
one’s hands in despair” (Mackintosh, 1998), despair presumably because there is a
widespread desire to find environmental effects that can be manipulated. So far, after
intensive searching, no one has found any, and the current consensus is that variation in
IQ reflects variation in the underlying biology rather than in the social environment. This
parallels the current consensus that mental illness is a biological phenomenon and that the
folk beliefs of half a century ago about causes—harsh toilet training, aloof fathers, etc—
have no empirical basis (Haier, 2003).

---

So . . . we don't have adoption studies, which would be nice, but we don't have studies showing that enviroment is the cause, either. So how do we settle the stalemate? Look at people with these disease alleles and see if they are smarter than non-diseased Ashkenazim. Which they seem to be. Which suggests a biological cause for some of the difference (it need not be all; in fact, as I pointed out way back, some have argued for a natural positive feedback effect in which small genetic advantages lead to cultural advantages and lead to success.)

I note that you said you were going to say something about statistics, but you seem to have got off that.

quote:

---

The second notion is that a high IQ necessarily leads to Nobel prizes and such. The allusion is that an IQ>140 makes you a lock for a Nobel. They don't say that, of course,

---

But you, with you pyschic powers, sensed that that was what they meant? Get serious. All they are going is establighing a relationship between the studies showing high IQs and actual achivement. You claim an understanding of statistics but you don't seem to grasp that we are talking about a statistical profile of a large group of people. Most Ashkenazi Jews don't win Nobel prizes. But more than one would expect do. Why?

quote:

---

because why would you ever speak clearly and carefully when trying to build a scientific basis for racism and discrimination.

---

Please explain how, if this hypothesis were true, it would justify racism and discrimination. It wouldn't.

quote:

---

You need to be smart to win a Nobel, for sure, but is it the extra one or two points that may or may not be attributed to Ashkenazim intelligence that puts them over the top or is it something else? I know what you and the authors think, but I also know that they have no proof.

---

It's not "one or two points." It's between one-half and one standard deviation, which gives them, as you say below, a big statistical advantage in term of genuis-level IQs. Why would that not lead to more Nobel prizes? It stands to reason. And you can cry "no proof" all you want, but without any explanation of your own as to the "something else" I tend to accept the idea that there is a connection between being smart and winning a Nobel Prize in the sciences.

quote:

---

Of course, I suspect that you will be tempted to sweep aside the foregoing as having nothing to do with statistics, and that's certainly your right. It would be wrong, but it's certainly your right. But here's where the wheels really start to fall off.

---

I probably don't "sweep aside" as much as I should. Rather I chose to answer it. But maybe you shouldn't promise an expose' on statistics and then serve up something completely different?

quote:

---

The authors fire out the fact that 23 per 1000 Ashzenazim will have an IQ >140 compared to 4 per 1000 of the population at large. If we take off our shoes and socks and do a little counting, something weird emerges: given that Ashkenzim folks make up 3% of the population and thus there are 33.3 times more non-Ashkenasi folks, we should still expect 33.3 x 4 = 133.2, 133.2 / 23 = ~5.8 times as many non-Ashkenazi folks to have an IQ better than 140. Keep in mind that we still have no proof that IQ >140 lead to a Nobel prize. But, even if it does, how do the authors explain the fact that Ashkenazi folks had such a strangle hold on the Nobels?

---

You've misunderstood the argument. Higher IQ doesn't lead to Nobel Prizes, according the authors; high verbal and mathematical reasoning aptitude leads to both. You've confused corrolation and causality.

Given that both are caused by something else, there is no reason to expect an exact statistical match between people with an IQ over 140 and Nobel Prizes. Such a correlation is not necessary or implied.

Now, if you wanted a statistical explanation nevertheless, it could be found in the idea that your average Nobel Prize winner is more intelligent than someone with an IQ of 140. Because the Ashkenazi IQ bell curve is right-shifted, the higher you go on the IQ scale, the more overrepresented the Ashkenazi will be. Thus it is entirely possible that Ashkenazi Jews do form 25% of the population with IQ of, say, 160 or better. The authors don't go into it because it's not important to establish a one-to-one correlation.

quote:

---

Could it be that there was something institutional going on? Could it be that the Ashkenazi folks were encouraged to undertake scientific research? Could it be that they came from families of influence who helped them by securing prime positions and/or funding for their research? Something isn't adding up here. Not surprisingly, the authors pay no heed to this.

---

But of course they did, see above. They conclude there is no evidence for such an assumption and proceede to provide evidence for their own hypothesis.

[ 13 July 2005: Message edited by: rsfarrell ]

quote:

---

Originally posted by Dex:
rsfarrell,
I have a feeling that a semantics skirmish is about to start, so I'll head it off with saying: no, I don't think Ashkenazi Jews represent a distinct race, but the authors almost undoubtedly do.

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Again we are graced with the presence of the wonderous psychic Madam Dex. Tell me this: does the word "race" appear anywhere in this 40-page paper? No, it does not. You are simply ascribing racial motives without any evidence of any kind.

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I have no reason to doubt that you read the paper. However, I have serious doubts about the comprehension side of things. From the very title of the paper ("Natural History of Ashkenazi Intelligence"), all the way down through the final conclusion ("high IQ test scores of Ashkenazim, along with their unusual pattern of abilities"; "pattern of high achievement among Ashkenazi Jews and the observed psychometric results"), the authors obsess about Ashkenazi Judaism to the exlusion of all other populations

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Nope, they mention other populations on numerous occasions, but it's a study of intelligence and disease mutations in Ashkenazi Jews, so they naturally get most of the attention.

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If they weren't so obsessed with ethnicity,

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Surely you can see that you're the one obsessed with ethinicity? Your pyschoanalysis of the authors is a joke.

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they would have couched the paper in terms of sphingolipid mutations, IQ, and natural selection.

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How do you talk about natural selection without saying what population is subject to the selection and why? It is precisely because this is a paper about natural selection and not just intelligence-enhauncing disease alleles that the authors focus on the population which showed up with a barrel full of them.

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Instead, though, at every turn, they go to painstaking lengths to differentiate Ashkenazi Jews from all other populations,

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They are different. So what? If the only answer to racists is that we're all the same, the cause of equality is in a bad way.

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often going well outside the scope of the paper and offering anecdotal, unsubstantiated, irrelevant claims in order to pursue their cause.

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Unfortunately, given your frequent misstatements of the paper's thesis and arguements, and the fact that you provide no evidence to support these claims, I'm going to have to -- what was the phrase you used? -- "sweep aside" your criticism in this case.

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As I read each part of the paper over again, their desperation becomes almost pathetic.

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Funny, I was just thinking the same thing about someone else. Seriously, this purple prose isn't getting you any closer to making a real case.

[ 13 July 2005: Message edited by: rsfarrell ]

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Who could afford a doctor when they were sick? Who could afford plenty of healthy food? Who could afford to get out of town when sickness swept through? Who could afford to educate large families? And the demographic data support that model, which is typical of pre-modern societies.

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Actually there's all sorts of pre-modern societies around right now that don't support that data.

However, there is in your statement an assumption that is also in the paper. That is, that those with greater wealth could afford better medical care.

I'll just point out that prior to the 1800's, medical care basically didn't exist and there was very little in the way of knowledge of healthy diets.

The only assumption that one could perhaps make is that the wealthy could afford to leave the city when the poor could not.

[ 14 July 2005: Message edited by: Erik the Red ]

How do you talk about natural selection without saying what population is subject to the selection and why? It is precisely because this is a paper about natural selection and not just intelligence-enhauncing disease alleles that the authors focus on the population which showed up with a barrel full of them.

But of course he was saying more than that, Namely that members of Ashkenazi ethno-religious group adopted by Appalachian hillbillies and visa versa say weren't even looked at to rule out the other known factors why certain groups may or may not display different talents in different areas. Kinda like Russian and German Jews being compared with each other in performance at chess first, then with other members of their neighbouring tribes. Standard sociological measure not all that different in idea than using placebo "contol" groups in medicine. Until thats established First, then it all just just begs the question again, like wealthy also meaning healthier and wise. But then we all know that much don't we...?

quote:Instead, though, at every turn, they go to painstaking lengths to differentiate Ashkenazi Jews from all other populations,

They are different. So what? If the only answer to racists is that we're all the same, the cause of equality is in a bad way.

Not just "different", more like "superior" and by extension inferior too. Bit harder to assume any sort of equality then, and I suspect that maybe one big reason why lefties are generally more susicious of this, more than righties are say. They too have their ideological biases as history has repeatedly shown, not for quite so noble intentions though.

quote:As I read each part of the paper over again, their desperation becomes almost pathetic.

Funny, I was just thinking the same thing about someone else. Seriously, this purple prose isn't getting you any closer to making a real case.

Not getting anyone any closer to anything, but thanks for thinking of me again anyhow.

[ 14 July 2005: Message edited by: Erik the Red ]

An enormous effort by cognitive scientists has gone into the search for differences in IQ between peoples of different geographic origins now living in the same country. In particular, numerous white American psychologists have been trying for decades to demonstrate that black Americans of African oprigin are innately less intelligent than white Americans of European origins. However, as is well known, the peoples compared differ greatly in their social environment and educational opportunities. This fact creates double difficulties for efforts to test the hypothesis that intellectual differences underlie technological differences. First, even our cognitive abilities as adults are heavily influenced by the social environment that we experienced during childhood, making it hard to discern any influence of preexisting genetic differences. Second, tests of cognitive abilities (like IQ tests) tend to measure cultural learning, and not pure innate intelligence, whatever that is. Because of those undoubted effects on childhood environment and learned knowledge on IQ test results, the psychologist's efforts to date have not suceeded in convincingly establishing the postulated genetic deficiency in IQ in nonwhite peoples.

This is an important point to remember.

[ 14 July 2005: Message edited by: Erik the Red ]

quote: Originally posted by Erik the Red:

Oh, and are you saying that American men who impregnated Vietnamese women carried some of those "Eurasian" genes back with them to their own isolated towns? News to me.

Absolutely they did, along with their Vietnamese brides. But that's neither here nor there. You've just picked a technical term from genetics that you don't understand and are getting all bent out of shape about it. It's kind of funny.

Bottom line, this population was genetically isolated, as genetic markers have confirmed.

Maybe not there but here. I was obviously Not refering to the few American men who were honourable enough to take their children home. My point was simply that men can of course pass along genes to women without bring those genes back to their own tribe. Same way that many Southern plantation owners left children with their slave women, adding to the "African" American gene pool while barely touching their "own" breeding population.

And I have real problems with the idea of such genetic "isolation" among Ashkenazi too, for reasons I'll get into more detail later (thought you'd have recognised them by now on your own) but not sure which genetic markers the authors were refering too exactly or even how they're using it so I can't say oneway or the other on this. I can think of several different possibilities there. A Bantu tribe in South Africa, for instance, claiming to be "sons of Solomon" turned out to actually have a unique genetic "marker" traced back to Jewish forebears, but of course share most other markers (and outward appearence) with neighbouring tribes.

quote: What I thought, they don't have much of anything really, no maps charting identifiable genetic differences regarding intelligence among individuals and groups. And its not "definitely" true, it's a hypothesis. At least at our present level of knowledge.

Maps??? There's lots of good stuff, I don't really know what you want, unless it is just whatever the authors' don't have. Did you read the stuff about the Gaucher's patients? What about the fact that all of these supposedly random mutations tie back into the functioning and development of the CNS? There's a lot of good evidence and ingenious deduction. I don't think you've dealt with it seriously, you just sneer at the evidence from a safe distance.

"Genetic maps" yes, a vague if popular term used nowadays. Try reading Newsweek more often. And yes, he did make some clever deductions which imply a clear relationship between increased intelligence and TaySachs, Gauchers on one hand and some problems with assuming that this concentration of disease was simply a matter of founders effect filtered through a demographic bottleneck, even I could appreciate that much. Once again however, I don't see these parallel lines as amounting to casual relationships and I could even guess at other possible reasons for some of this. That I'm going to leave off till I point out what I see as the major weaknesses in the paper more directly.

quote: Now, I'll post Diamonds comments about IQ tests and Blacks and boldface to clarify what he implies there, then I'll post the bit(s) that bugged me the most with comments, both of which you failed to address this time. Sooner than later.

So you're upset I haven't responded to something you haven't posted yet?

Not at all. I'm refering to previous unsucessful attempts to engage but I don't want to get into another extended pissing match either, maybe you just don't see the same issues as relevant, I don't know.

quote: If there's any straw men here you're the one responsible for constructing them. You continue to conflate this very narrow (and IMO implausible) paper into something of significance, to explain supposedly different levels of intelligence among "populations", or at least imply as much with few if any qualifying statements -at least until someone calls you on it and then you deny and cry foul.

I notice you don't have any statements of mine to back up this silly claim. The truth is you don't know what you're talking about, and I am spending an unconscienable amount of time explaining highly sophisticated science to someone who really doesn't have the background to understand it. That's my own fault. But don't you dare misrepresent my statements like you misrepresent the authors' arguments. Produce these sweeping claims, won't you? But of course you can't.

Again, I never claimed an scientific expertise but only arguing from sociological grounds, where it really does looks suspect to me, but then again, even without three whole terms in genetics etc I can still do that much easily enough. You said this yourself earlier. Now, you can save everyone time by simply stating whether you really do think that "some populations" really are "genetically superior in intelligence" than others. If you think this study has no real relevance to others in general (which I suspect it does) then it really isn't anymore important than any other which points out some small physical peculiarity among a particular population.

quote: RSF:Ya, heritability of intelligence is very well established.

Erik: Not quite. We know that intelligence resides in the brain which evolved into a more sophisticated and powerful instrument under selective pressures -over many millions of years. We know that humans are generally smarter by our standards than apes who are in turn smarter than reptiles etc. We know that some individuals are undoubtably geniuses in their fields and others are undoubtably mentally retarded, due to a variety of factors, sometimes environmental. It's even likely that intellect tends to run in families, as does the equally inexact term stupidity, but there too are bright children raised by slow parents and slow children raised by bright parents. (what most generally consider as such) Recessives? Probably. In some cases. And a dozen Other factors we know of and suspect.

We do *not* know that some "populations" are more intelligent on average than others, however, whatever that word is really meant to mean much beyond IQ tests and laurels.

Something that passes through families is heritable. It has nothing to do populations. Therefore to say intelligence is heriatable is not to claim anything about any population.

You can't keep simple distinctions like this straight, but you think you know all about genetics, and all about my supposed sweeping claims, which when examined will prove to be the product of more of your sloppy reading and ignorance of the subject.

And this of course is just what I meant. Read it again big guy, you might notice that that was the distinction *I* was making in the first place, which you then try to turn around on me. I only made it because you once again made an unqualified blanket statement that of course *could* be interpretted by others as saying that such heritability is also established among *larger* populations too. That was what we were talking about leading in, that's the nub of the whole thing, but enough of this, whatever you say dude. It's getting way late and my ISP is acting up again. I'll try to get closer to the heart of this tomorrow sometime, computer gods willing.

[ 14 July 2005: Message edited by: Erik the Red ]

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Originally posted by Erik the Red:
Ok, something Mr.Farrell's right about is my not posting enough data to back my own statements up, time to take a break from the verbal jousting for awhile.

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Maybe we could, I don't know, stop the verbal jousting? Personally, I don't enjoy it at all.

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For starters, this is what Diamond said (for those who haven't read it or forgotten) about IQ tests in Guns, germs and Steel, pg.20:

An enormous effort by cognitive scientists has gone into the search for differences in IQ between peoples of different geographic origins now living in the same country. In particular, numerous white American psychologists have been trying for decades to demonstrate that black Americans of African oprigin are innately less intelligent than white Americans of European origins. However, as is well known, the peoples compared differ greatly in their social environment and educational opportunities. This fact creates double difficulties for efforts to test the hypothesis that intellectual differences underlie technological differences. First, even our cognitive abilities as adults are heavily influenced by the social environment that we experienced during childhood, making it hard to discern any influence of preexisting genetic differences. Second, tests of cognitive abilities (like IQ tests) tend to measure cultural learning, and not pure innate intelligence, whatever that is. Because of those undoubted effects on childhood environment and learned knowledge on IQ test results, the psychologist's efforts to date have not suceeded in convincingly establishing the postulated genetic deficiency in IQ in nonwhite peoples.

This is an important point to remember.

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I agree completely. (Unfortunately, because I agree, someone will now be tasked with finding fault with what Diamond is saying.) His thoughts on this matter do not conflict with the authors'. The thesis has nothing to do with "genetic deficiency in IQ in nonwhite peoples." In fact, Diamond was, as far as I know, the first person to suggest the selection mechanism the authors are describing (see Diamond, J.M. (1994) Jewish lysosomes. Nature 368,291–292.) From the NYT article:

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A second suggestion, wrote Dr. Jared Diamond of the University of California, Los Angeles, in a 1994 article, "is selection in Jews for the intelligence putatively required to survive recurrent persecution, and also to make a living by commerce, because Jews were barred from the agricultural jobs available to the non-Jewish population."

The Utah researchers have built on this idea, . . .

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A functional polymorphism in the succinate-semialdehyde dehydrogenase (aldehyde dehydrogenase 5 family, member A1) gene is associated with cognitive ability

R Plomin1, D M Turic2, L Hill1, D E Turic2, M Stephens2, J Williams2, M J Owen2 and M C O'Donovan2

1Social Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, De Crespigny Park, Denmark Hill, London, UK

2Department of Psychological Medicine, University of Wales College of Medicine, Cardiff, UK

Correspondence to: MC O'Donovan, Department of Psychological Medicine, University of Wales College of Medicine, Heath Park, Cardiff CF14 4XN, UK. E-mail: [email protected]


Abstract

Succinate-semialdehyde dehydrogenase (SSADH) deficiency is a rare cause of learning disability. We have investigated SSADH to assess its contribution to cognitive ability in the general population in both case-control- and family-based analyses. Sequence analysis of SSADH revealed four changes affecting the encoded protein, only one of which had a minor allele whose frequency is even moderately common. We genotyped this functional polymorphism in 197 high-IQ cases, 201 average-IQ controls and 196 parent high-IQ offspring trios. The minor allele was significantly less frequent in high-IQ cases and was significantly less frequently transmitted by parents to high-IQ subjects than chance expectation. A previous study has shown that the minor allele encodes a lower activity enzyme than the major allele. These data suggest that higher SSADH activity is associated with higher intelligence across the general population. The effect is small, with each allele having an effect size translating to about 1.5 IQ points.

Molecular Psychiatry (2004) 9, 582-586. doi:10.1038/sj.mp.4001441
Published online 24 February 2004

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[ 14 July 2005: Message edited by: rsfarrell ]

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Originally posted by rsfarrell:
Maybe we could, I don't know, stop the verbal jousting? Personally, I don't enjoy it at all.

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