Crank science is as crank science does

I was sent this story about genes and IQ, and right from the beginning, my alarm bells were ringing. This is crank pseudoscience.

Gregory Cochran has always been drawn to puzzles. This one had been gnawing at him for several years: Why are European Jews prone to so many deadly genetic diseases?

Tay-Sachs disease. Canavan disease. More than a dozen more.

It offended Cochran's sense of logic. Natural selection, the self-taught genetics buff knew, should flush dangerous DNA from the gene pool. Perhaps the mutations causing these diseases had some other, beneficial purpose. But what?

At 3:17 one morning, after a long night searching a database of scientific journals from his disheveled home office in Albuquerque, Cochran fired off an e-mail to his collaborator Henry Harpending, a distinguished professor of anthropology at the University of Utah in Salt Lake City and a member of the National Academy of Sciences.

"I've figured it out, I think," Cochran typed. "Pardon my crazed excitement."

The "faulty" genes, Cochran concluded, make Jews smarter.

Why are European Jews prone to certain genetic diseases? My first answer would be to consider that they are a sub-group isolated by a history of bigotry from the outside, and strong cultural mores from the inside that promote inbreeding. These are variations amplified by chance and history.

I would not be offended by this. It's logic, too. Natural selection is important, but it's not everything — but so often, "self-taught genetics buffs" get the emphasis all wrong, and think of evolution as a machine that churns out generations that are relentlessly optimized for the best of all possible solutions, and these are the people who are also unsatisfied that evolution also churns out mistakes that are perpetuated over and over again. Errors happen, and their existence does not need an explanation; there is also no tendency by a benign nature to balance every individual's shortcomings with a beneficial mutation.

Mr Cochran's flaw is in his premise. There is no reason to assume that the frequency of every allele in a population must be the product of a selective advantage. The mathematics was worked out in the last century, and we know that even deleterious alleles can go to fixation in a population. His frenzied scribblings and off-the-wall database searches were driven by a need to reconcile the facts with his naïve and erroneous vision of evolution, and are not very convincing.

Here's another explanation: this isolated subgroup of Ashkenazi Jews also had a culture with a deep historical respect for scholarship, and emphasized and supported education and learning to a greater degree than the larger culture surrounding them. Their children therefore begin life with a leg-up on intellectual pursuits. We don't need a genetic explanation for their better performance (on average) on academic tests. Note also that this does not exclude a genetic component, but now at least we're talking about an environmental factor that favors selection for intelligence. Again, though, I haven't seen any convincing evidence for such a thing; personally, I think our intelligence is built on a shared genetic/development core that enables a wide range of kinds and degrees of intelligence to be expressed in response to environmental conditions.

But here's the final confirming evidence that Cochran is a crank and a non-scientist.

It would be easy to test the theory, said Steven Pinker, a Harvard cognition researcher: "See if carriers of the Ashkenazi-typical genetic mutations score higher on IQ tests than their noncarrier siblings."

Cochran and Harpending readily acknowledge the need for such experiments. But they have no plans to do them. They say their role as theorists is to generate hypotheses that others can test.

"One criticism about our paper is 'It can't mean anything because they didn't do any new experiments,' " Cochran said. "OK, then I guess Einstein's papers didn't mean anything either."

I don't agree with Pinker that it would be easy — there's going to be a lot of individual variation in performance, and I think it's very hard to split the variables of culture and genetics apart in these kinds of tests. But at least he's offering a positive approach to the problem, and that would be a good starting point.

But Cochran isn't interested in doing them? He's just a theorist? That's where he begins to sound exactly like an intelligent design creationist.

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In the new The New Republic, Steven Pinker does a fair and thorough assesment of the recent study asserting that Ashkenazi Jews have a genetic advantage in intelligence. According to the researchers (Gregory Cochran, Jason Hardy, and Henry Harpending), this selection took place from about 800 A.D.…
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So, by that logic. The gene that causes sickle cell anemia, has the advantage of also causing larger penis size.

I don't believe we know how prone Jews are to genetic diseases anyway. For various cultural reasons, we tend to know better the diseases to which they are prone.

Sub-populations are often used to study genetic diseases, because of the founder effect, and probably other factors as well.

Above all, none (or virtually none) of the genetic diseases known to afflict Jews have been correlated with intelligence in other sub-populations or in the population in general.

The fact is that if Jews happened to be genetically more intelligent than most people, that is likely due to selection and breeding mainly within that sub-population. And because of founder effects, and possibly due to valuation of intelligence over high physical health, certain genetic diseases happen to become correlated with Jews as well as intelligence. Again, if.

When are these idiots going to recognize that correlation very often is not causation, but only have common causes?

Glen D
http://tinyurl.com/6mb592

Sounds like a lead up to declaring the Jews are heading up the One World Shadow Government or something similarly ludicrous. Social and cultural underpinnings of "facts" like this always seem to get ignored in favor of biology and evolution, as if nature has been declared the unanimous winner in its fight against nurture and it isn't a contribution of both that form people into what they are.

But, then, it would actually be entertaining rather than the same old boring pseudo-science of this guy actually announced outright we were a part of the Jewnited States of AmeriKKKa (because I never miss a chance to bust out that absurdist parody).

Wow -- what a way to slip in the "Einstein Gambit" there at the end.

No, this guy is not as smart as Albert Einstein, and yes, Albert Einstein's theories (special relativity, general relativity, photo-electric effect, Bose-Einstein statistics, non-locality of quantum interference, etc.) really can be tested, and are tested every day. When I see electrons curving differently in a magnetic field depending on their speed (and hence relativistic mass), that's a test of special relativity.

I agree with you PZ -- this guy is not a scientist, but rather the antithesis of a scientist. "Hey -- Let's use big words to justify what we want to believe!" -- Not.

By spudbeach (not verified) on 20 Apr 2009 #permalink

How many crank points does Cochran get for comparing himself to Einstein?

Errors happen, and their existence does not need an explanation; there is also no tendency by a benign nature to balance every individual's shortcomings with a beneficial mutation.

This is I think one of the most common misunderstandings of evolution among religious people who think they accept it. Because they view it as God or Spirit's "method" of creation, they can't seem to stop this tendency to impute benevolence into the method itself. It's an extension of the idea that "everything happens for a reason." They're not talking about simple cause and effect, but a secret plan or purpose meant to guide each person down the path that is "right" for them. If Jews tend to get a disease, then there must be some social rationale for that, so they become stronger.

You only have to survive long enough to pass on your genes. Nature doesn't care about making you a stronger, better person, and it's not 'using' evolution to do so.

Gregory Cochran has always been drawn to puzzles. This one had been gnawing at him for several years: Why are European Jews prone to so many deadly genetic diseases?

What a bizarre question.

My mother comes from a heavily inbred population that is known to have genetic diseases observed almost nowhere else on the globe. It even serves as a model for the genetic study of inbred populations. There's nothing that need "make up" for this. Inbreeding has known consequences.

There is a joke we have which translates roughly to: if a married couple over there gets divorce, do they remain cousins ?

There was a Harry Turtledove short story along these lines. A highly distinctive ethnic group has been persecuted for centuries by the population at large and kept from outbreeding. In this case though, the sub group realized early on the effect this was could have on their genetics, and decided to use it to their advantage. The idea was that the pogroms and lynchings and stonings would filter out anyone not clever and smart enough to avoid such a fate. Not one of his better works.

By Jared Lessl (not verified) on 20 Apr 2009 #permalink

Speaking as a biology "layman", sickle-cell anemia is pretty much the "posterboy" for the idea that a harmful gene must confer some other benefit. So you get 50% of the population resistant to malaria at the cost of 25% being anemic. Therefore, all "bad" genes must work this way.

So, by that logic. The gene that causes sickle cell anemia, has the advantage of also causing larger penis size.

But it does increase resistance to malaria, which is where his argument comes from. His error is in assuming that all deleterious mutations have a positive trade-off. A purpose.

For the record, Herrnstein & Murray made a similar "finding" in their utterly debunked "Bell Curve" work back in 1994 (www.indiana.edu/~intell/bellcurve.shtml).

In that work they declared rather emphatically that while most dark-skinned people were inherently inferior, Ashkenazi Jews even outranked the other lighter-skinned people in intelligence. What is REALLY annoying about this, being of Ashkenazi Jewish descent myself, is how many Jewish folks decided to hop on the bandwagon with all this nonsense.

The topic has been studied extensively (just Google it) and there are very solid environmental factors that have led to whatever advantages or disadvantages people of Ashkenazi descent may have.

Nothing new here, carry on as your were...

By John in Bucharest (not verified) on 20 Apr 2009 #permalink

Anytime someone says they can't look for the information themselves, my BS alarm goes off. At least they can work with a team to find the information. I suspect Cochran really doesn't want it looked into, since he might be shown to be wrong.

By Nerd of Redhead, OM (not verified) on 20 Apr 2009 #permalink

Cochran and Harpending readily acknowledge the need for such experiments. But they have no plans to do them. They say their role as theorists is to generate hypotheses that others can test.

I would join PZ in criticizing Cochran for this, but I'm just an observer. My role on this blog is to read things so that other people might criticize them.

By Bostonian (not verified) on 20 Apr 2009 #permalink

re "einstein gambit"

He would do well to remember that at the time of publication, Einstein's paper also signified very little and was greeted with an overwhelming "so what?" It is not like the physics community read the paper and slapped themselves on the forehead with a collective "of course, why didn't I think of that?" It was not until it was experimentally verified that it acquired the significance it has today.

As a resident of Albuquerque, I apologize for Mr. Cochran's idiocy. Blame it on high altitude, dehydration, and sunstroke.

By Benny the Icepick (not verified) on 20 Apr 2009 #permalink

Einstein was very eager to have his theories confirmed by astronomers, and they were just as eager to conduct the observations that would confirm (or disprove) Einstein's theoretical work...and the evidence obtained from astronomical observation supports Einstein's theories.

Einstein would laugh out loud at this guy Cochran.

Einstein was very eager to have his theories confirmed by astronomers, and they were just as eager to conduct the observations that would confirm (or disprove) Einstein's theoretical work...and the evidence obtained from astronomical observation supports Einstein's theories.

Einstein would laugh out loud at this guy Cochran.

So did Einstein have Tay-Sach's? </snark>

Which came first, higher IQ scores or rearing environments like the Ashkenazi that promote intellectual pursuits?

Chicken and egg questions like this are tough to probe, but Pinker has the right idea. A good hypothetical experimental manipulation might look like this:

Take Ashkenazi jew babies away from their parents and rear them in different environments. Take non Ashkenazi babies away from their parents and rear them in the Ashkenazi environment. Then compare longitudinal IQ data (and other indices of "intelligence") within and between environments and genotypes.

Not perfect or plausible, but a good hypothetical starting point.

By Ahnald Brownsh… (not verified) on 20 Apr 2009 #permalink

Even worse than Cochran:

Jonathan Haidt, Edge Question Center 2009
http://www.edge.org/q2009/q09_4.html#haidt

"The protective "wall" is about to come crashing down, and all sorts of uncomfortable claims are going to pour in. Skin color has no moral significance, but traits that led to Darwinian success in one of the many new niches and occupations of Holocene life — traits such as collectivism, clannishness, aggressiveness, docility, or the ability to delay gratification — are often seen as virtues or vices. Virtues are acquired slowly, by practice within a cultural context, but the discovery that there might be ethnically-linked genetic variations in the ease with which people can acquire specific virtues is — and this is my prediction — going to be a "game changing" scientific event. ...

I believe that the "Bell Curve" wars of the 1990s, over race differences in intelligence, will seem genteel and short-lived compared to the coming arguments over ethnic differences in moralized traits."

Take Ashkenazi jew babies away from their parents and rear them in different environments. [...]
Not perfect or plausible

Or ethical...

Take Ashkenazi jew babies away from their parents and rear them in different environments. Take non Ashkenazi babies away from their parents and rear them in the Ashkenazi environment.

For the record, there was something like this in Israel, when many Ashkenazim families literally stole Mizrahim babies from Yemenite Jews brought to Israel (www.chayas.com/stolen.htm) and raised as Ashkenazim without any noticable effect. Likewise there are all the "lost Jewish babies" who were taken from their parents by the Nazis and adopted out and became fully integrated Germans once they were tracked down (www.jewishvirtuallibrary.org/jsource/Holocaust/children.html).

By John in Bucharest (not verified) on 20 Apr 2009 #permalink

Cochran and Harpending readily acknowledge the need for such experiments. But they have no plans to do them. They say their role as theorists is to generate hypotheses that others can test.

Oh piss off. Those of us that actually DO experiments are too busy testing OUR OWN hypotheses to do your work for you. We are, after all, theorists ourselves.

This assumes that intelligence has a selective advantage. Unfortunately, it's been my observation that the dumb jocks get laid more often. /snark off.

I had presumed that the prevalence of these deleterious genes was due to genetic bottlenecking from various pogroms against Jews and their subsequent (understandable) desire to keep their society close resulting in some shallowness in the gene pool.

Generate hypotheses that others can test? WTF?!

Sounds like they want to distance themselves from anything approaching actual work.

I want that job where I just come up with ideas and expect others to devise a means of testing them. Can I haz job?

Stupid stupid evo-psych bullshit. Trust a Pinker to be involved.

But hey, I'm an Ashkenazi Jew and I suffer from no debilitating genetic conditions, so I'm probably too stupid to poke holes in their idiotic arguments...

I think you've all glossed over something - "at 3:17 one morning".
Kind of odd to throw in that weirdly-specific time, don't you think?
Haven't we all seen enough nutjobs with John 3:17 signs?
Somebody's yanking someone here.

Cochran and Harpending readily acknowledge the need for such experiments. But they have no plans to do them. They say their role as theorists is to generate hypotheses that others can test.

To be fair, a good fraction of theorists don't do experiments because competent experimentalists won't let them anywhere near a lab. Even so, if you expect experimental confirmation, you have to demonstrate that your hypothesis is plausible enough for experimentalists to bother with.

As I understand it, when Einstein first proposed special and general relativity, the technology to test some of his predictions was simply not yet available. He most certainly didn't, when offered a easy and straightforward experimental test, say "let someone else do it, I'm just a theorist."

And my understanding is that Einstein's nobel prize was given for his work on the photoelectric effect, where his theoretical work was immediately verified by experiment.

BTW, is there not already a hypothesis floating out there that the Tay-Sachs trait does provide some kind of heterozygous disease resistance (TB? Cholera? - Or was that cystic fibrosis?) just like sickle cell?

The heterozygous advantage hypothesis is used to explain a deleterious genetic trait that persists over long periods of time in large populations at a rate higher than expected when mutation rates, drift and negative selection are considered. (ie somehow it resists elimination by natural selection) Or at least that's how I thought it was interpreted.

So this might apply to sickle cell, which is surprisingly common in a wide swath of large population groups. But Tay Sachs is incredibly rare, and localized to a few isolated, inbred populations. The same reasoning doesn't necessarily apply, methinks.

And it may be true that "dumb" jocks get laid more often, but the big question is, do they father more kids as a result, and do those kids produce more grandkids? It's r vs K redux.

"One criticism about our paper is 'It can't mean anything because they didn't do any new experiments,' " Cochran said. "OK, then I guess Einstein's papers didn't mean anything either."

Um, err... pardon me for bursting their bubble but actually, Einstein planned that his theories would be put to the test with a number of experiment which were described in his papers and only after those experiments were carried out and his theories seen to have merit did he get his fame and the respect of his peers.

So if you're not going to do the experiment yourself, get someone who does because otherwise your theory is only worth the paper it's printed on.

And yes, the reek of the Judaic/Masonic New World Order influence here is wafting in the air like cigar smoke.

"OK, then I guess Einstein's papers didn't mean anything either."

Let me theorize that all those who dredge up Einstein or Newton to counter routine scientific criticism are charlatans.

Ignoring the role that genetic drift plays in evolution would be a mistake. But, Cochran's ideas may have some merit.

There are a number of examples where a deleterious allele can produce an advantage in heterozygous individuals (eg. sickle cell carriers and malarial resistance). But, because intelligence is a multifactorial trait, we've seen that no one gene contributes substantially to an individual's intelligence (among other confounding factors is the method by which intelligence is measured and can we really define intelligence to test it empirically?). Thus, to claim that a single gene could be selected for via its heterozygote advantage on intelligence is certainly hard to swallow. However, there have been other studies that have shown that Tay-Sachs alleles may confer some protection against tuberculosis.

What? Where's all the Jason Statham talk? What the hell? I clicked the link to this entry hoping to read about "Crank" science...

By Bone Oboe (not verified) on 20 Apr 2009 #permalink

I'll also note that comparing yourself to Einstein alone is already worth 10 points on John Baez's Crackpot Index...

On the genetic disease issue: * shit, here I was about to make a point about lethality after child-bearing age, and they're all early onset genetic disorders... nvm, Pz's got it with the inbreeding more than anything else. The lineages on Tay-Sach's remarkably like those for haemophilia.

In order for Pinker to be right, you'd have to find a number of people who have the Ashkenasi mutations without being raised in their culture. That doesn't sound particularly easy to me...

The fact is that if Jews happened to be genetically more intelligent than most people, that is likely due to selection and breeding mainly within that sub-population. And because of founder effects, and possibly due to valuation of intelligence over high physical health, certain genetic diseases happen to become correlated with Jews as well as intelligence. Again, if.

The only rational attack on that idea out of 30-some-odd posts. Surely people can do better than "Evo-psych is bad because it conflicts with my liberal sensibilities", and bad slippery-slope analogies to eugenics and Naziism? There are evolutionary impacts on human nature... and outside of small inbred populations where sexual selection has a profound impact, attempting to link something like intelligence to a specfic ethnic group is absurd (far more similarities than differences between groups). Claiming that everyone, as individuals, starts out perfectly equal but for environmental factors is utopian, and absolutely false.

Not that it defends Cochran's hypothesis, which is demonstrably horseshit.

This is my first comment on this amazing blog. Sorry for the bad english, it is not my first language.

Cochram is absolutely right when he says that his job as a theorist doesn't require the need to actually experiment his theories. Einstein didn't do such thing, as well. The difference is, some of Einstein's theories made a lot of sense before they were experimented. This Cochram theory seems to be made out of thin air, based, apparently, on fallacious premises. Who is going to spend time and money on it? Cochram should work on his theory, try to attract the scientific community and help the beggining of the experiments. Otherwise, his work as a theorist will really mean nothing.

By Felipe B. (not verified) on 20 Apr 2009 #permalink

Unfortunately, when I saw this:

"... the self-taught genetics buff knew..."

I pretty much stopped reading. While there are certainly exceptions, in my experience, the self-taught suffer from having both a bad teracher and a poor education.

And it may be true that "dumb" jocks get laid more often, but the big question is, do they father more kids as a result, and do those kids produce more grandkids? It's r vs K redux.

No, the "real question" is whether "dumb jock"-ness is an inheritable trait.

Well, crap! I wish I had read this post BEFORE reading their book(The 10,000 Year Explosion: How Civilization Accelerated Human Evolution). It was rather "meh", but being a layman I didn't question their theories too far.

Is there anything I need to know before reading Jerry Coyne's "Why Evolution is True"? Like...is evolution false and you are all part of a conspiracy?

Surely people can do better than "Evo-psych is bad because it conflicts with my liberal sensibilities"

Yes, how about "evo-psych is generally bad science because it argues for wildly speculative and completely unsupported connections between genes and behaviour as if they were facts."

I agree with Felipe that a theorist need not test his own theories - sad, but historically true.
My beef is with the theorists who set themselves up as the ultimate intellectual authorities on all things scientific, even as their speculative 'theories' get trashed left and right by actual researchers.
Barrows and Tipler come to mind.

That line about 'our job is just to generate theory' reminded me of an excellent archeology paper by Kent Flannery, "The Golden Marshalltown: A Parable for Archeology in the 1980s" (1982, American Anthropologist, v.84, n.2, pp. 265-278). It's also the only paper I've come across written as a narrative, and it's actually really funny.

In it, he contrasts his "dig and test" generation of archaeologists with those who graduated in the 1960s and 70s, who are far more interested in "generating theory" or synthesizing the work of others than actually going out there and digging. The 'born again philosopher' of the 1960s is exceptionally proud of his work, where he never has to get dirty, producing things such as the bleedingly obvious "Laws of Archeology":

1. Prehistoric people did not leave behind in the site examples of everything they made.
2. Some of the things they made have disintegrated and cannot be found by archaeologists.
3. Objects left on a sloping archaeological site wash downhill.
4. Lighter objects wash downhill faster than heavier objects.

Needless to say, the 'Old Timer' is not impressed.

@reggie> There are plenty here who will disagree with me, but all evo psych isn't necessarily wrong... it just needs to be based on legitimate genetic/ev/ bio findings, and often isn't. The "just-so-stories" approach is similar to what Ev. Bio went through with adaptationism, and those didn't necessarily turn out to be untrue when checked. I guess my rambling point is that all you need to do with their book is look for the evidence they cite, or fail to cite.

I don't know the studies on Ashkenazi very well, so I wonder if anyone knows: ARE they prone to more genetic diseases? It was my understanding that their historic isolation made them a good population to study, not necessarily the frequency of diseases. Is Cochran possibly asking something similar to "why are identical twins prone to genetic diseases?"

@ Tulse> yep, that'll pretty much work... I was hoping that someone could produce a rational argument rather than an emotional knee-jerk reaction. Sorry, it irks me when people trash an entire discipline without appearing to grasp why, and without considering that something coming out of it might be valid with the proper grounding.

As a European Jew, ethnically, I don't have a problem with anyone pointing out that we have a higher predisposition to disease. It's like someone pointing out that people of African descent have a higher predisposition for sickle cell. That's how it is. Whatever.

I'd be interesting to see a good deal of testing data on the subject. As someone who generally likes Pinker, I think that it's a little shortsighted to say any testing on disease is going to be easy. Environmental factors are a serious problem (especially with people of different cultural backgrounds).

Anyway, I'm still curious if anything turns up.

I disagree with PZ about the "ethics" of theory and experiment. If Cochrane were arguing against the testability of his hypothesis or trying to explain away results that undermined his theory, then he would be a crank. If someone followed Pinker's suggestion, did the study, and came up with nothing, and Cochrane said "that doesn't matter", then he would be a crank. But there are plenty of (for example) mathematical theorists who don't test the empirical reality of their models themselves, but rather wait for them to be tested by experimentalists with Hubble or VLA time. Many cosmologists would be cranks by this definition. Whether the same person happens to build the model and also do the experiment has nothing to do with the truth of the proposition.

The second point, and one which PZ doesn't address directly but many of the comments do, is that this kind of research is automatically racist. Are there certain questions we're not allowed to ask? If I'm Native American (which I am, partly) can I tell you not to make genetic claims about "my people" because you're white and you're automatically some kind of conspiracy-theorist? We get very uncomfortable where biology encounters ethnicity, and given the history of twentieth century science, this isn't necessarily inappropriate. But the fact is there's a pile of evidence suggesting that there has been strong, recent (last ten thousand years) selection. Read John Hawks' blog if you want a taste. The awkward implication is that different groups of humans would have different traits, some of which are plainly obvious (like skin color) and others of which may actually affect behavior. To make the point, let's kick Caucausians off top of the Victorian great-chain-of-being and ask "What if East Asians actually are genetically smarter than whites?" (Excepting John Kwok.) Yes, this is a minefield, ethically, politically, you name it, not least of which because it brings every racist out of the woodwork claiming scientific proof of their bigotry - but pretending such differences are not possible *in principle* and dismissing this research out of hand as automatically racist crankery isn't a viable approach, and this will be increasingly true as genetics and neuroscience converge in the near future.

By Mike Caton (not verified) on 20 Apr 2009 #permalink

@Glen Davidson

Actually this seems to go well past "Correlation is not causation" to "Wishful thinking is not correlation or causation". This makes the "Just-So" stories of the 1960's and 70's anthropologists and social scientists seem downright well thought out.

The difficulty with comparing cutting edge theoretical physics (astro physics) is that so much of the theory can be backed my mathematical equations and proven that way. The experiments run in reality that really make these theories are needed but many other people have already examined the math of the theory and found it to be plausible. In many other fields there isn't this distinction between having the mathematical component and a separate physical test.

I really wish it were as easy to say "I came up with the theory and now you have to test it." My dissertation would be causing me a lot less stress! And I'm only in the social sciences.

By Siveambrai (not verified) on 20 Apr 2009 #permalink

John in Bucharest is right, this one is far from new, however lets not let revulsion blind us to the possibility since it is not a priori unreasonable. Oh and Lady, the hypothesis is that it is the carriers of the genes that benefit, not those with two copies that get disease. Sickle Cell anaemia is similar, carriers get protection from malaria, sufferers get ill.

There is a suggestion that a number of the genes involved play roles in membrane function/processing in the brain, but then most of the human genome is expressed in the brain at some time, it's how you build humans with the same number of genes as a mouse. It's not what you've got but how you use it. Bear in mind that in Europe the selection pressures on the Ashkenazim were truly huge. The slander always had a basis. It was easy to believe the Jews were part of a world wide banking cartel when a lot of the bank managers were Jewish. They were so because their possible employment had been strongly restricted. They could not be labourers, could only work in finance or be jewellers and a couple of others. In that situation the stupid could not thrive, how could they make a living except by providing for their fellow Jews? who were often kept very poor. This is very often grossly oversold, but that does not mean there is therefore no possibility of truth in it.

Anyway it's crank science because these guys claim to be 'theoretical biologists' yet they can't be bothered enough to read the literature to know they are not being original.

By Peter Ashby (not verified) on 20 Apr 2009 #permalink

Among other minor quibbles, it would appear that the gene for Tay-Sachs has some benefits against tuberculosis when heterozygous.

No special brains required, just being locked up in a crowded ghetto.

By D. C. Sessions (not verified) on 20 Apr 2009 #permalink

Betz # 28:

Re 3:17 one morning.

If there's anything I've learned over a lifetime, it is this: Any earth-shattering insight/realization acquired around 3 AM is worthless until it has been thoroughly examined in daylight.

And usually, even then.

Can't add too much to the discourse here that hasn't already been said, but I think any differences in IQ between small populations is likely to be a founders' effect. One disease of the Ashkenazi not mentioned so far is Bloom's Syndrome. It is autosomal recessive and about 1 in 110 are carriers. A mutation of the helicase protein for DNA replication, it is hardly a candidate for a gene improving intelligence.

One thing to keep in mind, these diseases are not always restricted to the Ashkenazi. Tay Sach's is increased in the Irish and French Canadian population as well. Any IQ studies on them? The point was driven home to me when, while lecturing on lysosomal storage diseases, I mentioned the French Canadian connection and a student suddenly erupted with interest. She was Jewish and her husband was Arab. They had had the perfect statistical expression of Tay Sach's in their children...one normal, two carriers, and one with the disease who died. The husband had not been tested because they thought they were safe until the last child was born. Turns out his mother was French Canadian.

I don't agree with Pinker that it would be easy — there's going to be a lot of individual variation in performance, and I think it's very hard to split the variables of culture and genetics apart in these kinds of tests.

I'm afraid I have to disagree with PZ and side with Pinker here. The idea is fairly easy to test. The two problems brought up by PZ are:

* "a lot of individual variation" - but trivial individual variation is always dealt with by good study design, such as a large enough sample size. No more problem here than with most statistical tests.

* "hard to split the variables of culture and genetics apart" - but the variables of culture would be controlled for by looking at enough siblings, who would, on average, share the same culture.

I think these assumptions are reasonable, personally.

That being said, I don't think Cochran's hypothesis even remotely plausible. Genetic drift, etc. has got to be pretty strong in a small, rather isolated population. No need to invoke the "onerous concept" of adaptation here.

Eureka, I've got it! Jewish rye, with seeds!

"... generate hypotheses that others can test." That's a description of an idea rat not a theorist. Idea rats generate ideas and the convince credulous managers (usually engineers) that others should waste their time testing these ideas.

As far as I've ever known certain groups of Jews are subject to various genetic conditions because they indulge in arranged marriages and not "marrying out". A bit like European monarchy and haemophilia (sp?) I think.

Whether this applies just to Jews in Europe or worldwide I wouldn't know. I live in Europe (well, England, but it's close) so the only arranged marriage types I know live here, and not elsewhere.

Because of this breeding within such a small genetic group these particular Jews have adopted some sort of "blood test" (surely a genetic test, no?) which returns a simple "good to marry" or "bad to marry" type answer from the samples taken from the prospective couple.

Er... sorry... having spent more than enough time on the fringes of Jewish society I probably should know more about this stuff, but I don't. In fact I've never actually heard anyone talk openly about the "blood test" and am only aware of it at a distance (so correct me if I've got something wrong). I do know that the "no marrying out" or arranged marriages are far from universal amongst Jews (else I would never have been born in the first place), in fact I think it's probably quite rare in modern society but I'm pretty sure that it still goes on (the last case I know of personally was maybe 8 or 9 years ago, but necessarily I am not what you would call deeply connected with those families who indulge in arranged marriages and such like).

Quite what the fuck any of this has to do with the Cochran chap's deranged fuckwittery I'll never know. But there you go.

the fact is there's a pile of evidence suggesting that there has been strong, recent (last ten thousand years) selection

In terms of intelligence, there's a pile of evidence suggesting that there has been strong selection extremely recently, as in 3 IQ points per decade. It sure must be a vicious world out there to drive evolution to raise IQ about ten points per generation. Either that, or IQ is hugely impacted by environment and other non-genetic factors -- I wonder which might be true...?

There's a long section on this topic in the final chapter of Nicholas Wade's "Before the Dawn," which I just finished reading. I don't think it's quite as crackpot as we're making it out to be. On the other hand, that book does give a little too much free reign to the indulgent side of Evo-psych.

I'm uncomfortable with the wholesale bashing of evo-psych I'm reading here. I agree that it's practitioners often go very far overboard in formulating their just-so stories. But there's just too much interesting and provocative data to dismiss the entire discipline. Indeed, it would be truly astonishing to me if it were NOT the case that our evolutionary context didn't shape our cognitive predispositions. Evo-psych is new and just finding its feet. It needs some time to mature, but it shouldn't be rejected too flippantly.

By wet_bread (not verified) on 20 Apr 2009 #permalink

Hmm. An article about crank science and European Jews on Hitler's birthday ?
I'm finding some Irony here.
Irony, and I'll point out that it's nothing more than the same tired old canard that the Jews are "clever" in the sense of being crafty and scheming.

"Why are European Jews prone to certain genetic diseases? My first answer would be to consider that they are a sub-group isolated by a history of bigotry from the outside, and strong cultural mores from the inside that promote inbreeding."

Why change the label here? Bigotry is bigotry, regardless of whether it originates from "strong cultural mores".

As a physics Ph.D. candidate it's been a while since my college classes on physical anthropology, but I'd like to bring something up that no one seems to have touched:

IQ != intelligence. Many of the commentors seem to use IQ and intelligence synonymously. Even PZ's main post seems to imply it. Perhaps things have changed in the last 6 odd years, but to my recollection, all IQ tests really measure is your ability to perform well on those types of standardized tests. Someone who has an IQ will also typically have a high SAT score, but that's about all.

In terms of real-world attributes, IQ correllates best with socioeconomic status. That is, if your parents are rich and successful, you'll tend to do well on the tests. This all comes back to the fact that the original IQ tests were designed so that an upper-class, rich, white male would perform quite well and contained numerous cultural biases. In my recollection, they were used as an anti-immigration tool, with incoming immigrants being divided into classes based on their IQ.

Sure, the tests have changed quite a bit since then, but I've never seen any good studies that show that the biases have been completely removed, or that IQ has been shown to test for any innate "intelligence" quality someone may have. Is this really the kind of method you'd want to use to discriminate between phenotypes for a gene like the one that causes Tay-Sachs?

BTW, if I'm completely wrong about this I hope that someone who's a little more of an expert in the field will post a follow-up.

I'm having trouble understanding the hostility towards Cochrane myself.
I don't see anything anti-semitic in his idea, and it has some degree of plausibility, therefore I wouldn't call him a crank,(over-enthusiastic amateur, maybe).
Maybe my standards of crankdom are too high.
If you accept that IQ is partially affected by genetics, which most people do these days,(right?),

Combined with the effect of the persecution of the Jews by the Europeans which often forbade them to own land or serve in the military,thereby driving them towards professions which favor the intellect,(medicine, law etc.),

Combined with the Jewish tendency to not marry outside of their communities...
How could that NOT have the effect over time of increasing the average IQ of the Jewish population in comparison to the Euopean population at large?
Cochrane's hypothesis about genetic diseases tied into this larger notion seem superflous but not crankish, but then again I'm kind of a self-taught genetics buff myself.

So can anyone spell out the objection to this idea in civilized terms?

By shoshidge (not verified) on 20 Apr 2009 #permalink

@30 amphiox said:
As I understand it, when Einstein first proposed special and general relativity, the technology to test some of his predictions was simply not yet available.

Well actually in Einstein's second 1905 paper on Special Relativity, "DOES THE INERTIA OF A BODY DEPEND UPON ITS ENERGY-CONTENT?", where he derives what is now written E=mc**2, Einstein wrote at the end:

It is not impossible that with bodies whose energy-content is variable to a high degree (e.g. with radium salts) the theory may be successfully put to the test.

If the theory corresponds to the facts, radiation conveys inertia between the emitting and absorbing bodies.

Anyone curious about the derivation of E=mc**2 can read the English translation from which my quote above came from. It's a very short paper, likely it only took one page in the journal in which it was published.

http://www.fourmilab.ch/etexts/einstein/E_mc2/www/

The results of the previous investigation lead to a very interesting conclusion, which is here to be deduced.

George

P.S.
The 1905 paper on the photo electric effect explained experimental observations. It may have been the first practical use of Plank's quantum theory.

By George Martin (not verified) on 20 Apr 2009 #permalink

I love when you said :
"Errors happen, and their existence does not need an explanation"
That is just awesome

By robotaholic (not verified) on 20 Apr 2009 #permalink

If you accept that IQ is partially affected by genetics, which most people do these days,(right?),

The evidence for this claim is not that strong, and as I noted above, the Flynn Effect (which is IQ scores increasing about 10 points a generation in recent decades) suggests that environmental effects are far larger. Genetics may establish upper and lower bounds, but it does not determine IQ.

Combined with the effect of the persecution of the Jews by the Europeans which often forbade them to own land or serve in the military,thereby driving them towards professions which favor the intellect,(medicine, law etc.),
Combined with the Jewish tendency to not marry outside of their communities...

What is evidence that the smarter Jews in those communities had more children? What we're interested in is inclusive fitness, and not personal success. In many communities those who are less financially successful have more children, since offspring provide an important source of cheap labour.

How could that NOT have the effect over time of increasing the average IQ of the Jewish population in comparison to the Euopean population at large?

See above. The Just-So Story may sound plausible on the surface, but it relies on so many assumptions that it is just naked speculation.

PZ:

Worst post evah!

You both over-insult and under-insult Cochran simultaneously -- and complete miss the point.

If Cochran makes a strong theory, it's not "crank" at all to claim to be a theorist and not an experimentalist. The "Einstein gambit" is perfectly respectable, even if one isn't an "Einstein" -- Einstein wasn't an Einstein when he initially published, was he? If he's producing testable, fully consistent theories, then Cochrane is perfectly allowed to produce theoretical structures that other labs test.

That's how it's done in physics -- some folks are stronger at experiment, some folks are stronger at theory, they both publish and knock each other down (or up). There's no reason that it couldn't (and as a matter of fact, it is) done that way in biology. It's not some kind of special privilege -- it's the normal division of labor.

Cochran's problem appears to be that he's a shitty biological theorist. He's no Gould, he's no Dawkins, he's no Meyer (the one from the '30s). There is no damn way that he's made a testable, consistent theory out of mapping from specific lipid genes to specific intellectual traits --- 'cause it's not doable.

We don't have sufficient knowledge of the components. Anyone who uses IQ as a measure is an idiot -- The Bell Curve was debunked quite a while ago. We're not talking about going from a gene for melanin to a coloration -- we're talking about going from one set of ill-defined genes to the most ill-defined trait of all!

But you miss it all, because you'd rather sling crap about "theorists". Cochran is a crank because his "theory" isn't a theory at all, anymore than "ID" is a theory.

It's not because it's "just a theory". It's not a theory -- so it can't be "just a theory".

Cochran is also the guy who came up with the idea that homosexuality is more than likely caused by a virus.

By Lynn David (not verified) on 20 Apr 2009 #permalink

Thanks Tulse,
I don't think anyone has suggested that genetics solely determine intelligence, I would go so far as to say that genes may be responsible for establishing an upper threshold of possible IQ, after that, environment takes over to determine if that potential gets realized.

As for a mechanism by which prosperous Jews have more children, if you've met any traditionalistic Jewish mothers, you will know how being a doctor will make it a lot easier to meet and marry their daughters.
This may be a cheeky stereotype, but I believe it has basis in fact.
As for many children and cheap labor, if you can't own land you can't farm, which would be the profession most likely to benefit from a large brood.

By shoshidge (not verified) on 20 Apr 2009 #permalink

I may be wrong on this, its not my field, but the comments have sparked a memory of something Stephen Jay Gould said about research into "intelligence," he found the research was profoundly shaped by social views of the researchers.

I remember that around the time he said this (about 10 years ago) the American Psychological Association was going to give a life time achievement award to a developer of many of the standardized IQ tests although the researcher was portrayed as an avowed eugenicist. (Cattell?). Perhaps the whole thing is a canard, because intelligence testing is an oxymoron.

I may be wrong on this, its not my field, but the comments have sparked a memory of something Stephen Jay Gould said about research into "intelligence," he found the research was profoundly shaped by social views of the researchers.

I remember that around the time he said this (about 10 years ago) the American Psychological Association was going to give a life time achievement award to a developer of many of the standardized IQ tests although the researcher was portrayed as an avowed eugenicist. (Cattell?). Perhaps the whole thing is a canard, because IQ testing is an oxymoron.

I don't think anyone has suggested that genetics solely determine intelligence, I would go so far as to say that genes may be responsible for establishing an upper threshold of possible IQ, after that, environment takes over to determine if that potential gets realized.

Right, and traditionally Judaism has emphasized education and scholarship, no? So a cultural explanation is just as plausible a priori, and doesn't require making unquantified assumptions about the relation between genetics and intelligence. (Such explanation, however, still has the problem of unquantified assumptions about the relation between intelligence and material success, or between material success and inclusive fitness.) Such a cultural/environmental account would also be in line with the Flynn Effect.

As for a mechanism by which prosperous Jews have more children, if you've met any traditionalistic Jewish mothers, you will know how being a doctor will make it a lot easier to meet and marry their daughters.

And black people can dance really well and are great athletes, and Irishmen are feisty and drink a lot. Again, do you have any quantitative data that looks at inclusive fitness (which is the issue under debate), or just ethnic stereotypes? And do you have any quantitative data that indicate the relationship between intelligence and being prosperous in that community? Is the strength of that relationship (if there is one) sufficient to provide significant advantage in inclusive fitness?

This may be a cheeky stereotype, but I believe it has basis in fact.

You have data to back that up, or just your own "observations"?

To be clear, I'm not saying that the theorized mechanism is a priori impossible. Nor am I saying that this is a question that shouldn't be asked because of "political correctness". What I am saying is I am profoundly tired of intellectually lazy armchair speculation being passed off as deep scientific insight, especially when such speculation is curiously in line with (and used as justification for) common stereotypes.

"But Cochran isn't interested in doing them? He's just a theorist? That's where he begins to sound exactly like an intelligent design creationist."

That's not true. Read his comment on GNXP, explaining the difficulty in arranging such an experiment (it's too un-pc).

--------------------------------------------------------------------------------

"gcochran
We have talked to some people about doing such a study. A researcher in Israel was interested, but met massive lack of enthusiasm from the powers that be: try to guess why. It might not be what you would think. Someone else I know wanted to do it until his adviser pointed out certain likely side effects - I believe the phrase "unemployable pariah" was used. That, of course, if his results supported our work.

I asked an associate of Plomin - one interested in our ideas - and was told there was no chance of it ever happening.

Some of the events in our push toward publication might also clarify the picture: one editor who had expressed interest called up, crying, and explained that the dean had said he'd close down the journal if our article was published. In another case, an editor rejected on the grounds the the Ashkenazi Jews had been farmers in the Middle Ages: which mistaken idea I figured he had picked up from Fiddler on the Roof, which he admitted was the case. When I told him enough to correct thaat misapprehension, he went on to say that we might well be right (judging in part from hsi teaching experience), but that of course his journal would never publish anything so controversial. So why a six-month review process when the answer was foreordained? Ya got me.

In another example, someone interviewing at the University of New Mexico was asked about sphingolipid mutations and intelligence (it was related to his thesis) and he said he couldn't afford to think about it - he wasn't Harpending.

I doubt if any university IRB in the country would approve it. I doubt if the Feds would ever fund it - with the exception of one possible scenario, but probably not even then.

Still, there are ways. It'll happen.
Email | Homepage | 04.20.09 - 1:54 am | #

http://www.haloscan.com/comments/raldanash/8591875144070170308?

"Perhaps the whole thing is a canard, because IQ testing is an oxymoron."

Except it predicts numerous group outcomes in education, occupational performance, & at a macro level economic performance (see Rindermann).

Also, there are physical correlates in cortical thickness & myelination.

"In healthy adults, greater intelligence is associated with larger intracranial gray matter and to a lesser extent with white matter. Variations in prefrontal and posterior temporal cortical thickness are particularly linked with intellectual ability.

'Relationships between IQ and Regional Cortical Gray Matter Thickness in Healthy Adults'
Cerebral Cortex 2007 17(9):2163-2171;

"By comparing brain maps of identical twins, which share the same genes, with fraternal twins, which share about half their genes, the team calculate that myelin integrity is genetically determined in many brain areas important for intelligence. This includes the corpus callosum, which integrates signals from the left and right sides of the body, and the parietal lobes, responsible for visual and spatial reasoning and logic (see above). Myelin quality in these areas was also correlated with scores on tests of abstract reasoning and overall intelligence (The Journal of Neuroscience, vol 29, p 2212)."

http://www.newscientist.com/article/mg20126993.300-highspeed-brains-are…

The molecular genetics of Tay-Sachs disease support the idea that the loss of the hexosaminidase A enzyme, which is required for the degradation of glycosphingolipids has an adaptive advantage. There is more than one mutation in the Ashkanazi population that result in hexosaminidase A loss. The most common, a single base insertion resulting in an abnormal, non-functional protein product is 70%, but there are others that are found at a higher frequency than in other populations. This argues against a founder principle or genetic drift for this particular disease, at least. It does not say what that adaptive advantage is.

Slatkin (1994) argues that a founder effect associated with a population bottleneck associated with the Jewish Diaspora could explain the elevated gene frequencies, but I feel that his model fails to explain multiple types of mutations affecting the same enzyme.

Other mutations affecting the glycosphingolipid degradation also occur at a higher frequency in the Ashkanazi population (Nieman-Pick disease, Gaucher disease, and Mucolipodosis IV, which is not an enzyme loss, but a loss of the ability to import lipids into the lysosome for degradation. Since all four such mutations affect glycolipids, which are common in neural tissue, that is the basis of the proposal that they yield elevated intelligence (in the heterogyzous state, since the homozygous state is reproductively lethal).

Note that the loss of the enzymes in question also occur in other populations at frequencies consistent with random mutations. And, the pattern of mutation type is much different from that found in the Ashkanazi population, supporting the conclusion that these mutations are fixed in this population, although that can occur through an adaptive advantage, random drift, or a founder effect.

Multiple gene defects being associated with a single condition has a precedent in resistance to malaria. Not just sickle cell trait (heterozygous for beta-S-globin, but hemoglobin C, alpha-thalassemia, beta-thalassemia, glucose-6-phosphate dehydrogenase deficiency, and some others have elevated gene frequencies in populations where malaria is endemic--actually, compare against the incidence of malaria 100 years ago before eradication efforts. I remember reading a review by David Weatherill a number of years ago that claimed that ten or twelve different mutations are associated with being from regions of malaria.

So, the Cochran-Harpending idea is possible. I think that there is a lot of hand waving about selective conditions for intelligence in their proposal. But, the data already exist to test it, as Pinker proposes. Not just for Tay-Sachs, but for the other diseases. The gene frequencies of carriers are high enough (1:31 for Tay-Sachs and 1:16 for Gaucher disease for example) that enough data already exist. Pick your favorite test (IQ, SAT, etc.) and see what comes out when carrier and non-carrier siblings are compared--if you are brave enough to do experiments in this field! Just look at some of the comments above.

If you want to get references and descriptions of some of these defects, check out the Online Mendelian Inheritance in Man (OMIM) at the NCBI.

Quite amusing to read the people here saying IQ is some meaningless artifact. Here is a summary of the neurobiological correlates.

www.loni.ucla.edu/~thompson/PDF/nrn0604-GrayThompson.pdf

Also, the later research by Thompson with a nice scan image:

"By comparing the brain scans of twins, scientists discovered that the quality of the fatty tissue that insulates neural wires is largely inherited. The parietal lobe, which is involved in logic and mathematics, is 85 percent genetically determined, whereas the visual cortex is about 76 percent, and the temporal lobe, which is involved in learning and memory, is only 45 percent genetically determined."
http://www.technologyreview.com/biomedicine/22333/page2/

No I don't have data to back this up and I am not engaging in 'deep scientific insight'.
I can't speak for Cochrane,(I haven't read his book), but I am by definition an armchair speculator, which is what you do on internet forums, if I were an insightful scientist researching data on this issue I would be publishing it in a journal, not here.
I was raised by a Jewish stepfather in a neighborhood full of Jewish families, and even though none of them were very religious, there was a palpable sense that they did not take anyone without a University education seriously for anything, especially as potential dating material for their daughters.
This is not unique to Jews either, I've seen the same trait among many traditional Asian families as well.

What I am profoundly tired of, is the rage and fear this topic stirs up in some people, especially people who make sport of ridiculing the histrionic overeactions of others to different topics,(like evolution or tax hikes, for instance).
New Earth creationists are cranks, energy healers are cranks, anally-probed UFO abductees are cranks.
Cochrane,(and Steven Pinker for that matter), may be wrong, but neither of them seem stupid, nor are they cranks

By Shoshidge (not verified) on 20 Apr 2009 #permalink

I think it is quite premature to jump from genetic alterations in pathways related to metabolism of certain lipids found in neural tissue to "aha! this must be related to intelligence."

Setting aside the not so small caveat that we don't actually have a good definition of what "intelligence" actually is, cannot reliably quantify of classify the myriad components that constitute it, or reliably determine what mix of said components may or may not have what kinds of effects on what sort of behaviors that may or may not have impact on the putative reproductive success of any hypothetical given individual in a particular historical cultural milieu (that has changed with time, of course).

Just because something is expressed in the brain doesn't mean that the only possible function is something to do with intelligence! Even if you accept the conjecture that there is some positive selection advantage, there are a whole host of other possibilities, some of which are much easier to test experimentally than intelligence. For example, energy efficiency in metabolism, effects during early development of the nervous system in relation to environmental stressors, resistance to mental illness in stressful environments, protection from trauma, resistance to infectious diseases, etc.

Remember that 'g' is the thing that most researchers now look at. Also, as Gottfredson notes:

"Competing definitions verbal definitions do not negate either the existence of a suspected phenomenon or the possibility of measuring it. What matters is not unanimity amoung proposed definitions or descriptions but construct validation or "dialogue with the date" (Bartholomew, 2004, p5)

Gottfredson, L. S. (2009). Logical fallacies used to dismiss the evidence on intelligence testing. In R. Phelps (Ed.), Correcting fallacies about educational and psychological testing (pp. 11-65). Washington, DC: American Psychological Association.

http://www.udel.edu/educ/gottfredson/reprints/2009fallacies.pdf

"data" not date.

For the record, several of the different comments here are at least partially correct in identifying factors that resulted in modern Ashkenazim.

A) Internally, you had the Ezran (i.e. from the time of Ezra on) precepts on "Jewishness" which added the notion of ethnocentric (i.e. basically racist) Jewish identity. During Temple Judaism, we were a missionary faith, making new converts and NOT at all based on an ethnic "Am Israel" or what-have-you. The very term "Presbyter" meant a new convert to Judaism long before anyone had ever heard of Christianity (look it up). Ezra and his "reforms" converted Judaism from an all inclusive faith to one that was primarily based on ethnicity, though the option of conversion remained open (but not easy). The net result in the age of rabbinical Judaism was that Jewish people believed (and still believe in many cases), that one must marry fellow Jews to be a good Jew (disregarding the fact that according to the Torah, most of the prophets - Moses, Abraham, Isaac, &c. married non-Jews).

B) Externally, after most of the latter Roman Empire adopted Christianity as the "official" religion of European civilization and as the Empire was replaced with Christian-based feudalism (based on feudal oaths, made within a Christian framework); Jews became the consummate "outsiders" of Europe. They were not to be trusted because their their belief structure was utterly incompatible with a system of faith & trust that was based on Christianity and its rewards (heaven) and its punishments (hell). While Jews had similar beliefs, these beliefs were not based on Jesus. This put Jews outside the framework of mainstream European civilization. Generally our people were either i) a special "pet people" of the monarch who functioned throughout the realm outside of feudal restrictions based on the aristocracy; or ii) convenient scapegoats for whatever happened to be going wrong at the time, from plague to bad weather. Either way, European Jews remained separate from mainstream European society. They were not permitted to be farmers/peasants (as these were bound by Christian oaths to their feudal lords); they were not permitted to be soldiers (as these were bound by Christian oaths to their commanders & their lords); they were obviously not allowed to be Christian clergymen (the academic leaders of the age); and they could never accept leadership roles because leadership was based on maintaining status through, yet again, Christian oaths. However, Jews found their niches, as people always do. Medicine (based largely on first classical knowledge that Jews kept alive and later on borrowings from Dar-el-Islam); independent traders (usually under a special sanction & tax of the monarch) that moved from village to village selling wares (the continuance of Roman retail trade); money-changers (exchanging the currency of one realm with another, esp. in the Holy Roman Empire - Germany & Italy - where the currency would change every few miles) (one of the founding elements of international finance and surely the the foundation of modern Forex trading); and specialized artisan work (the major industries - steel smithing, iron-mongering, &c. were in the hands of either trained peasants or urban guilds) especially relating to jewelry and the like all became virtually Jewish monopolies. The monarchs won because these "Jewish industries" were completely dependent on the monarch's patronage (and he generally got a good tax from it as well) and the Jews benefited as they had a niche to fill in society, i.e. they could live. Of course being outside of the feudal framework, Jews were generally despised by those within it; the aristocracy, the urban guilds, and the peasantry, that is, the vast majority of European people. As feudalism collapsed and enterprising non-Jews began developing alternative systems (secular medicine, international banking & finance, specialized artistry, &c.) Jews in general (there were a few exceptions) became much more marginalized and generally confined to ghettos and/or particular districts (most famously the Czarist 'Pale of Settlement'). Throughout the entire period, Jews remained quite separate, at first as feudalism's exception and then as general social pariahs.

Both internal Jewish rules (the Ezran reforms) and external pressures (not being Christian in a world that was based on Christian fealty) resulted in the Ashkenazim becoming a very distinctive ethnic sub-group that was heavily intermarried. It should also be noted that in general, one of Ashkenazim's primary attributes was that many of them were literate and numerate - as a product of Jewish education - in an age when very few people were (and often the educated non-Jews were Churchmen that the monarchs rightfully distrusted as representing the interests of the papacy over those of the monarchs, a lesson in the fallacy of mixing church & state). Further, the successful Jews, those able to take a wife and raise and provide for their children tended to be the brighter ones (a general environmental factor) in that their success was not based on physical prowess but intellectual resourcefulness.

All of these environmental factors - Jewish internal rules, external social pressures, and the resulting consequences of both - resulted in roughly 1500 years of separation and specialization (say from about 500 CE to present). The inbreeding has certainly resulted in the larger incidence of particular genetic diseases and recessive deleterious traits. Likewise the same factors - not biological, but ethnic and cultural, have resulted in a subgroup where success - both in life and in mating - is (or at least was) directly tied to education and "intelligence" (by conventional definition).

However, this unique circumstance notwithstanding, the same applies to many other people who have faced similar pressures - think Armenians and Roma (Gypsies) - and there is certainly nothing particularly odd about it. As proven by the Nazi example (see reference above) if you take an Ashkenazi baby and give it to a non-Jewish family, it becomes a member of its new culture and society; likewise, if you take a non-Ashkenazi child (as happened among the Mizrahim in Israel, reference cited above) and raise it in a Ashkenazi household and environment, it too fully integrates into its new culture and society.

Quite simply, trying to differentiate Jews - or any other subgroup, again think of the Roma (Gypsies), and I am living in Romania right now where there are a LOT of Roma - from the rest of humanity based on biological criteria is exactly the kind of thinking that justified the Shoah. Whether it is meant as a compliment or a complaint it is a false label that has a proven track record of horrible consequences. Ethnic and cultural differences are real and undeniable, nevertheless we are all people that are essentially the same in terms of biology and genetics; remove the individual from his ethnic and cultural environment and he his no different than his new peers.

By John in Bucharest (not verified) on 20 Apr 2009 #permalink

Not completely Crank but a lot of inbreeding disorders

These guys are not complete crackpots because they do offer a testable, though offensive, hypothesis, but it will be hard to test it or find people politically willing to test it.

Ashkenazi Jews have all sorts of birth defects caused by inbreeding. One such friend of mine points to his 40 year old mouth where some of his baby teeth still remain and have not been been replaced by adult teeth. Does this mean that Jews have evolved to the "new human" that doesn't need to eat solid food? Or do the development pathways for lack of adult teeth also make him smarter?

What is the genetic makeup of Ashkenazi Jews - Some say that they are 60% European while others say they are only 10%. Basically this is a minefield into which I do not want to step.

By monkeyboy (not verified) on 20 Apr 2009 #permalink

Disappointing post, unfortunately, from PZ.
He's left out a critical fact that has resulted in a lot of people being misled on the topic. The critical point is that we are not talking about a single mutation here that seems to be increased in an inbred population. That, of course, can easily be explained by founder effect/genetic drift mechanisms and may have no particular selective advantage whatsoever. To have a number of separate rare mutations affecting the same gene or genes in the same selective pathway or producing the same phenotypic effect, as in the current topic, can be indeed strong evidence for selection. Whether this selection is for intelligence or for something else (such as resistance to some infectious disease) is at least testable - either in the Ashkenazi population themselves or in other populations - Irish or French Canadians - who have higher percentages who are heterozygous for the mutation.
The large scale genomic studies underway, SNP analysis, genomic sequencing etc, combined with a proper phenotypic assessment will at least give us some way of determining an answer on this matter without specifically designing a study to answer an ethically difficult IQ/race question in isolation from all other factors. The hypothesis here (heterozygous sphingolipid pathway mutations can give higher intelligence) should be answerable without recourse to comparing different populations who may have very different environmental factors confounding the issue.
To propose a testable hypothesis is not being a crank. Dismissing the hypothesis out of hand without recourse to evidence one way or the other, however, is another matter.

@Tulse

What is evidence that the smarter Jews in those communities had more children? What we're interested in is inclusive fitness, and not personal success. In many communities those who are less financially successful have more children, since offspring provide an important source of cheap labour.

You are forgetting that selection doesn't care about how many children you beget, it cares about how many of your children survive and breed. Children can provide cheap labour, but only if you can feed them. I suggest you read up on conditions in the Ghettos.

By Peter Ashby (not verified) on 20 Apr 2009 #permalink

Haven't we all seen enough nutjobs with John 3:17 signs?

Pointless and belated nitpick, but it's John 3:16 signs the nutjobs have.

What a lot of people who don't buy a genetic component in intelligence are forgetting is sexual selection. Autism has been steadily increasing in Western societies, not as much as the vaccine deniers say and some is better diagnosis, but it is going up. Why? well my speculation is that it is a result of industrialisation and the freeing up of populations in terms of choice of marriage partners. This idea was tweaked by the observation that your chances of being autistic are higher if both grandfathers were engineers or scientists (mine were both engineers but I'm not autistic, just gauche).

Now this may not seem significant until you think about for exactly how long has it been very likely that both your father and mother had an engineer for a father? How long have we had a sufficient density of engineer's and scientists in society for their children to meet and fall in love enough for the stats of that study to be possible?

Now before you jump down my throat and tell me that autism is not the same as intelligence I will agree with you. I suspect it is however a side effect of a certain sort of intelligence that is useful in industrialised societies. Like all those jokes about Engineers, like how do you know an engineer is attracted to you? he looks at your shoes. Now think about the sort of woman who would fall in love with that sort of guy. Intelligence is a turn on for some people, I simply don't fancy stupid women no matter how phwoar! they may be. We got married as students but my wife has degrees in maths and compsci and is doing an MBA. Stupid she is not. Yet she fell in love with gauche me.

The big question here is whether the effect, population wide, is significant in any way other than that slow steady rise in autism. All I'm saying is those shouting that it is all culture and education have no more evidence that this is the case than I do. The majority of the increases in the Flynn Effect (a fellow Kiwi Flynn) are almost certainly cultural/educational. But we cannot prove there is no genetic component because it is not PC to do the work, up to now. Lets stop speculating and get studying, starting with devising ways to test intelligence. Perhaps for a start we need to stop it being an all or nothing effect. There is more than one type of intelligence. Read Jared Diamond on the New Guinea Highlanders for one thing.

By Peter Ashby (not verified) on 20 Apr 2009 #permalink

Whoa. I think that's the fist PZ post I disagree with.

Sure, the hypothesis sounds ludicrous and there is a very faulty understanding of evolution being displayed here. But not all scientists are experimentalists. As someone doing theoretical physics, my calculations don't really have much to do with experiment. I make general deductions that should be applicable in terms of how to interpret certain experiments, that is all. I also am working on models inspired by experiments that should give experimenters some reference on what to look at and what qualitative trends to look out for. I do not, however, make experiments. If I come up with a new hypothesis, I'll try to get experimenters to test it out; I won't try to test it out myself, I just don't have the laboratory, skills, and know-how.

There is more to science than experiments. Developing the theory and its interpretation is important too, and in mature sciences is often done by specialists in that domain. Developing theory with no connection to experiments isn't science, but that doesn't mean the guys developing the theory must be the same guys testing it out. There is room for theorists.

selection doesn't care about how many children you beget, it cares about how many of your children survive and breed

Of course -- now what is the quantitative evidence that small differences in intelligence made large differences in inclusive fitness in this population? Surely you'll agree that this is necessary to establish this hypothesis?

Autism has been steadily increasing in Western societies

As I understand it, that depends greatly on what studies you read. The consensus (such that there is) seems to be that increased awareness, broadening diagnostic criteria, and case substitution account for the increase. Some researchers do argue for an increase, and of those a small subset do suggest that this increase is due to "selective breeding" of those with technical/"geeky" characteristics, but that is by no means the consensus position, even in those who agree that there is an increase in the condition.

But we cannot prove there is no genetic component because it is not PC to do the work, up to now.

I at least have been clear that this is not a matter of "being PC", but of lack of any hard evidence. And there has been a ton of research looking at intelligence and IQ, with very equivocal results.

Lets stop speculating and get studying, starting with devising ways to test intelligence. Perhaps for a start we need to stop it being an all or nothing effect. There is more than one type of intelligence. Read Jared Diamond on the New Guinea Highlanders for one thing.

I agree with all these sentiments.

josh: Except it predicts numerous group outcomes in education, occupational performance, & at a macro level economic performance

And? There are endless "correlates". Give me a mechanism, or shut up. Correlates is the science of the lazy or dishonest. When we can map up from specific proteins up to specific behaviors, the problem will be tractable -- but until then, this discussion is fully devoid of scientific content, and is purely an ideological game.

We could spend centuries correlating without gaining anything -- since the correlates may reflect almost any underlying function. It's an inverse problem. Why waste time and money discussing a method which cannot answer the given question? Why can't folks just accept that certain methods can not solve certain problems, and look for actually answerable questions?

As I said, my impression is that it's purely ideological. Do some real work.

We could spend centuries correlating without gaining anything -- since the correlates may reflect almost any underlying function. It's an inverse problem. Why waste time and money discussing a method which cannot answer the given question? Why can't folks just accept that certain methods can not solve certain problems, and look for actually answerable questions?

Umm.. because it's still useful to have some idea of what's creating whatever effect we're observing, rather than being completely clueless? Because you aren't going to find a cause without having the correlations from which to derive it? Perhaps most importantly because there are complex interactions underlying a good deal of biology, so you can't find a single solution that fits the entire model?
I agree that implying causation from correlation is fallacious, as would everyone else, but biology isn't math... claiming that it's necessary to reduce it all the way back or your findings are useless is absolutely ludicrous. One simply has to take care to note where the weaknesses of the argument lie.

The idea that Jews are "smarter" (whatever that means) because they respect education makes a hell of a lot of sense. The Puritans that came to this country had the same thing going for them. The guy who had deeply studied the Bible and was able to discuss it intelligently (as opposed to the guy who gave great sermons) was the most important guy in each parish. The Puritans ended up founding Harvard only 6 years after their first large migration because they respected learning.

It's disturbing to me how many people are clearly trashing Cochran without actually reading his book, or the article that preceded it on the same issue (which is easy enough to find on google). In it, he anticipates and rebuts most of the objections raised here, including that the high incidence of these diseases among Jews is caused by inbreeding or the founder effect, and provides pretty good evidence that 1) Jews were pushed in extremely disproportionate numbers into relatively g-demanding positions for 800 years in Europe, and 2) that those Jews who did will in these positions had many more children survive to adulthood.

His theory makes sense, but more importantly (since a lot of "just so stories" make sense) it explains why disorders that are so common among Jews involve sphingolipid metabolism. Or, as the article itself says:

"Genetically isolated groups often have higher rates of certain diseases. But of the more than 20,000 human genes, only 108 are known to be involved in sphingolipid metabolism. The odds of Ashkenazi Jews having four sphingolipid storage disorders by random chance are less than 1 in 100,000, [Cochran] calculated."

Clearly, SOMETHING has been selected for here. Given the conditions in which Jews lived during the Middle Ages, intelligence is a possibility. And Cochran does provide evidence in his book that carriers for some of these disorders have higher IQs than average.

The idea that Jews are "smarter" (whatever that means) because they respect education makes a hell of a lot of sense.

How can it 'make a hell of a lot of sense' when you don't know what it means? You might want to settle on one PC argument instead of contradicting yourself in one sentence like this. Either defend the idea that 'smarter' is an empty and meaningless construct, or admit that the Jews really are smart (to the best of our ability to measure such things) and see if you can impute it all to nurture.

The article from PZ is a nice smear. I assume he read Cochran's paper, which means he would be aware that the thesis is not based on a single deleterious SNP but on the existence of a whole complex. Further that some genetic conditions that are disproportionately prevalent among Jews (e.g. torsion dystonia) are associated with higher intelligence.
He also deliberately misreads Cochran's comment on doing the experiments. Cochran would love to see the experiments done; he himself just isn't in that line of work.
Anyway, it's not that important. Keep it up all you like; history will find you in the same box as the defenders of epicycles and phlogiston theory in due time.

"... bigotry from the outside, and strong cultural mores from the inside ..."

One of the things that keeps bothering me about the English language is the judgmental shading of so many words. Not every language requires you to have two words for each and every thing: one word to use when you approve of it, and a different word to use when you disapprove of it. Your "terr.rist" is my "freedom fighter", and so forth. It is difficult to write a neutral sentence when you have no neutral words to do it with.

Suppose you are trying to describe a mutual prohibition against outbreeding, e.g., a prohibition that is applied by both the minority population and the majority population. Why, the population you approve of has "strong cultural mores", while the other population is "bigoted". Works in either direction.

But the real culprit here is the English language. It is hard to avoid writing a sentence like that when the words out of your dictionary keep slanting one way or the other. Like walking on scree.
.

By Voting Present (not verified) on 21 Apr 2009 #permalink

Your "terr.rist" is my "freedom fighter"

This one, though, is a common confusion. "Terrorist" refers to a method, and "freedom fighter" to a goal. It's entirely possible to be a terrorist and a freedom fighter at the same time; indeed, it's a fairly common combination.

By David Marjanović, OM (not verified) on 21 Apr 2009 #permalink

PZ said this.

"but so often, "self-taught genetics buffs" get the emphasis all wrong"

and this

"But here's the final confirming evidence that Cochran is a crank and a non-scientist."

You have got to be kidding, PZ. It's one thing to disagree with another's hypotheses, but you know as well as I that this guy is the real deal as a scientist and a theorist and that while he's "self-taught" in that he hasn't a degree in the field (ohhhhh, big deal!) he puts other who have such degrees to shame.

A "crank"? A "non-scientist"? If you believe that, you are stupid; if you don't, you are purposely misleading those who don't follow the fields of evolution, genetics, evolutionary biology andthe like, and therefore don't know much if anything about Cochran.

Pathetic.

PZ,

By demonstrating your inability to follow Cochran & Harpending argument, it is you who are suspect as a scientist.

Your stated objections to Cochran & Harpending's theory, are not only non-scientific, they are in fact lies.

Next some of you idiots are going to be calling Paul Ewald a crank.

BTW, familiar with Ewald and Cochran's infectious causation of disease theories, written about in '99? Happen to notice all the lab work being done NOW, work that is connecting the dots from all kinds of ailments (including behavioral ones) to chronic infectious disease?

Cochran, an amateur? What kind of blog IS this?

Self-righteous moralists like Tulse can shut up with their empty indignation.

Look, we have two groups (Ashkenazim and European Americans) that we know are separable with "with 100% sensitivity and 100% specificity" using a couple of genetic tests. We also see that we consistently find reliable group differences in IQ between those two across nations. Whether or not you believe IQ measures "true intelligence" or not is immaterial. Call it "the fuzzy factor" if you wish. All we care about is that two traits that covary with ancestry also must covary with each other. The research is also "useful" in the sense that "g" (the instrumental proxy for IQ) is a fairly robust predictor of all sorts of highly salient social variables like criminality, high school drop-out rate, adult occupational status, etc. And "g" is not self-evidently the statistical ghost some insinuate in the sense that increasing IQ tends to comport with a greater amounts of grey matter in the brain, and faster cognitive processing speed. We ARE inching closer to a physical interpretation!

Indeed, why should we default to a cultural explanation, when we have no idea the mechanism or units of transmission of cultural evolution, and we have a pretty darned good synthesis and understanding of genetic transmission and the evolution of group variation? If anything, whenever we come across a group difference between any two populations of distinct lineage, we should immediately be willing to test for a genetic explanation! Defaulting to a cultural theory of group differences is just STUPID in this scenario.

Me, myself, I'm trying to find evidence of the research chops that enable a guy working at a third-tier public university to call Cochran a "crank".

I won't hide the fact that I'm an admirer of Cochran's whole corpus of research, especially his work on disease. Hopefully that won't matter, as I aim to stick closely to matters of fact.

- Myers suggests Ashkenazi are inbred, resulting in increased magnitudes of genetic drift. This is an extremely offensive suggestion (just kidding). Seriously... this idea should be highly testable; shouldn't inbred populations show increased homozygosity? I believe Cochran suggests this hasn't been found.

- Myers suggests it is difficult to test this hypothesis. This is totally mistaken, assuming we leave aside purely political factors that make the study difficult to do in practice. The words "I think it's very hard to split the variables of culture and genetics apart in these kinds of tests" suggest Myers has totally overlooked the usefulness here of a segregation analysis. This simply means comparing siblings bearing a certain allele to siblings in the same family who do not bear it; obviously this controls for culture perfectly if one grants that each family has one uniform culture, so that siblings all share the same culture.

There is more to say but much of it seems to have been covered by others.

By Eric J. Johnson (not verified) on 21 Apr 2009 #permalink

Someone up above pointed out that it's Cochran who posed the gay pathogen hypothesis. I don't know if the poster offered that as a simple point of information, or if it was intended to suggest Cochran was a "crank."

If his purpose was the latter? Sir, just give it a bit of time, just a bit of time. It's not a crank theory at all.

I'd like to place bets in Vegas on it.

Self-righteous moralists like Tulse can shut up with their empty indignation.

I would welcome you pointing out where I was moralizing. My point is that making unsupported claims is bad science.

two traits that covary with ancestry also must covary with each other

But that doesn't meant that they necessarily covary because of genetics (and to claim that necessity is, again, bad science). An alternate hypothesis is that Ashkenazi Jews value education and learning more than European Americans, and thus environment is the link between IQ and ancestry. Empirical work is needed to distinguish between these two hypotheses, but it should be clear that a genetic explanation is not the only option.

increasing IQ tends to comport with a greater amounts of grey matter in the brain

Did anyone claim there was no connection between cognitive skills and the physical aspects of the brain? Again, for this point to be at all significant, you'd have to rule out any impact of culture and environment on IQ and on brain development, which seems exceedingly unlikely given that IQ has risen significantly in the past two generations in Western cultures.

whenever we come across a group difference between any two populations of distinct lineage, we should immediately be willing to test for a genetic explanation!

So test! But don't just blather about correlations that are several times removed from the question at hand, and don't wildly speculate without any hard evidence. Provide the hard numbers, demonstrate the actual connection. That's how science is done.

(And I would hardly call "European Americans" a "distinct lineage".)

"... bigotry from the outside, and strong cultural mores from the inside ..."

One of the things that keeps bothering me about the English language is the judgmental shading of so many words. Not every language requires you to have two words for each and every thing: one word to use when you approve of it, and a different word to use when you disapprove of it. Your "terr.rist" is my "freedom fighter", and so forth. It is difficult to write a neutral sentence when you have no neutral words to do it with.

Bilge. I quote thee an adage: "It's a poor craftsman who blames his tools."

While it's true that, due to a series of what amount to historical accidents, English does have a rather large number of roughly synonymous lexical units, the charge that the words themselves have "judgemental shading" or that there are "no neutral words" is just silly. Words acquire connotations to go with their denotations. This occurs in all languages; as they are used by their speakers, differences in the intended meanings of common usages shade this way or that. It's unavoidable, and, frankly, not that undesirable. I prefer a messy natural language to, say, IngSoc.

And your examples are lame. I somewhat doubt that "bigot" or "bigotry" were ever not terms of opprobrium, and how is "strong cultural mores" a word? It's a phrase, where modifiers are employed to shade the meaning. "Mores" is pretty neutral, on its own. See David's objection to your opposition of "terrorist" and "freedom fighter" and add to it my challenge to find me a language in majority use in a developed nation where those two concepts could not be rendered distinct.

I'm not claiming that the polished and precise use of the English language is the easiest skill to learn. But don't blame the language if you haven't acquired it.

PZ, as a longtime reader and admirer of your blog, I have to say I am disappointed with your flippant repudiation of Cochran's views as well as the narrow-mindedness of some in the comments section who have accused Cochran of having some kind of Zionist racist agenda. I would have liked a reasoned rebuttal of Cochran's PNAS paper as well as his paper on the Ashkenazis. Plus, although I would have liked to see more enthusiasm on Cochran's part, there is nothing wrong in advancing a theory and having others test it; there are scores of such examples in the history of science. What separates "us" from "them" if we too start attacking not the science but the people who are behind it?

By Lactate dehydr… (not verified) on 21 Apr 2009 #permalink

CJO and DM don't like my objection to PZ's sentence in which he places the "bigotry" of one population in contrast with the "strong cultural mores" of another. But they merely quibble. Languages do differ, and I believe that English makes it particularly difficult to separate value judgments from logical arguments.

But let us separate the argument about the English language from the problem of PZ's sentence:

A. Did PZ actually intend to express approval of one population and disapproval of another population over the same prohibition?

B. Did PZ fail to express what he meant here? (Whether or not the English language is to blame.)

C. Or did PZ's sentence carry none of the approval and disapproval that I attribute to it? (Marlowe #68 takes the same view I do, but prefers to fix the problem by disapproving of both populations.)

Looking back, the thing I regret is my inapt comparison of navigating the English vocabulary with walking on scree. The scree is all sloped the same way. A better comparison might have been to the act of leaping among ice floes too small to bear the weight. Poor footing for such a journey!
.

By Voting Present (not verified) on 21 Apr 2009 #permalink

"Plus, although I would have liked to see more enthusiasm on Cochran's part, there is nothing wrong in advancing a theory and having others test"

Cochran has explained on Gene Expression that he has talked to people about doing it and come up against considerable politically motivated resistance.

"gcochran
We have talked to some people about doing such a study. A researcher in Israel was interested, but met massive lack of enthusiasm from the powers that be: try to guess why. It might not be what you would think. Someone else I know wanted to do it until his adviser pointed out certain likely side effects - I believe the phrase "unemployable pariah" was used. That, of course, if his results supported our work.

I asked an associate of Plomin - one interested in our ideas - and was told there was no chance of it ever happening."

http://www.haloscan.com/comments/raldanash/8591875144070170308?

I have to agree with Tulse that unsupported assertions are certainly bad science. It is possible that placing a stronger cultural value on education and intelligence fosters a rise in IQ within an ethnic group. It is also plausible that there is a genetic component that plays a role here. From ecological studies of other phenotypic traits in organisms, there tends to be a blend of the two... direct genetic correlations rarely play out on their own without an environmental factor that affects expression. The issue that arises in this sort of debate, of which I'm guilty at times as well, is that we forget to consider the evolution of any particular human trait in the same manner that we consider that of any other organism. We're not special, but we are definitely anthropocentric, which is why when something conflicts with that viewpoint (or our previously held moral convictions, etc, see posters above dismissing out of hand without examining the science) we tend to forget this.

I never truly appreciated the strength of feeling against evo-psych here, or elsewhere. The field has merit when the attempts at explanation can be empirically backed, but it raises so many hackles it doesn't seem to be given the opportunity. Points to Tulse for approaching this rationally, despite our lack of agreement.

> I have to agree with Tulse that unsupported assertions are certainly bad science.

Is this in reference to the Ashkenazim hypothesis? I am pretty sure that Cochran has never suggested it be taken as a fact, and has pointed out the need for it to be tested.

Hypothesization is A-OK in general, the moreso when the hypothesis is highly testable - as this one, minus political obstructions, is. It's also not unseemly for a hypothesis to get some attention when still far from robustly evidenced in some peoples' opinion; that is very common for medical hypotheses. On the other hand, it would not be bad for human sciences hypotheses on touchy subjects to meet a slightly higher standard before being widely aired. In this case, though, there are multiple convergent lines of evidence in favor of the theory even though the simple, definitive test has not been done. The theory is rather convincing IMO even today. And people have taken a natural interest in such a fascinating subject and tour de force of multidisciplinary investigation, which can't really be helped.

> It is possible that placing a stronger cultural value on education and intelligence fosters a rise in IQ within an ethnic group.

Just to be annoying :) I'll point out that almost any trait of the Ashkenazim that you or anyone would term cultural may in fact be significantly genetic in origin. Indeed, that seems to be far from unlikely, given that quite a few different personality traits have shown a heritability around 0.5 in studies coming from multiple different research groups.

By Eric J. Johnson (not verified) on 21 Apr 2009 #permalink

""Just to be annoying :) I'll point out that almost any trait of the Ashkenazim that you or anyone would term cultural may in fact be significantly genetic in origin. Indeed, that seems to be far from unlikely, given that quite a few different personality traits have shown a heritability around 0.5 in studies coming from multiple different research groups.""

This point sounds completely illogical to me.

The first sentence in and of itself is akin to a person who has recovered from a headache being unclear on whether her recovery was due to the aspirin she took or prayer.

Culture, learned, developed and evolved culture, has had a very real impact on society - to reduce its impact to naught because of a silly hypothesis is ludicrous! By denying the role of human culture, you are also denying the one tiny element that distinguishes us from other animals - you are denying human creativity and ingenuity. You are also hinting towards the protestant concept of 'predestination'.

I don't doubt that humans are still evolving, but setting up such divisions is eugenics, pure and simple. These are the exact scientific techniques that allowed the Nazi's to justify the Holocaust and Europeans to justify slavery, apartheid and colonialism - yet the early eugenicist's studies were never found to be been fruitful. Why do you think they can be now? Why do you say " The theory is rather convincing IMO even today"?

Can you please provide more information on this, for example:

- the sources
- the "few different personality traits have shown a heritability around 0.5 in studies"
- the "multiple convergent lines of evidence in favor of the theory"
- the different research groups you mention?

Biological determinism has never, ever aided scientific research and i for one don't want to have to tackle that inane concept again.

#106
"PZ, your stated objections to Cochran & Harpending's theory, are not only non-scientific, they are in fact lies."

Sources please...really! Where are the lies? It's not like PZ is the first, or only scientist to have aired these objections.

@121,

Nobody is accusing Cochrane of thought crime or claiming he should have no freedom of speech. People are just calling him out - what's that saying, "exceptional claims need exceptional evidence".

You however, are implying that those that criticise him should shut up and leave him be - thereby denying his critics freedom of speech. How do you reconcile that in your (il)logical mind?

I have been researching this guy for the last week and I haven't found many compelling arguments supporting him - that's why I am here trying to find one. So far, his supporters on this list have been full of hot air and few facts...in the last 24 hours his enamoured fans seem to have decided to come to this blog and jump to his defence - failing miserably.

While researching Cochrane, I HAVE come across a highly neurotic group of fans that he has picked up - and yes, they do sound like creationists - highly offended that you could criticise the Great Leader, hyperbolic and little to no science to back up their support for his hypothesis. That's not Cochrane's fault though, strange ideas that have little to no science to back them up tend to attract strange people.

Mary, PZ is getting some flack from this post for the simple reason that he's committing exactly the same mistake that he's accusing Cochrane of making. As I'm sure you are aware from undergraduate human genetics alleles, even deleterious ones, can become fixed due to either selection or to more random processes like genetic drift. A classic way of determining whether selection for a particular alteration is occurring is to look to see whether we are looking at a single mutation (possibly genetic drift) or several independent mutations (much more likely in the case of selection).
Read PZ's piece again and see whether he implies that Cochrane and Harpendings hypothesis is based on the latter scenario (the actual situation) rather than the former (which PZ implies).
I certainly agree that 'exceptional claims require exceptional evidence' yet exceptional evidence in science is often the results of many individual pieces of smaller evidence. Cochranes hypothesis is falsifiable. In this piece he, himself calims that the experiment needs to be done. He may, however, not be the best person to test it out (wouldn't an independent experimenter be better in such a contentious field of study). In fact the ideal scenario is probably not to devote precious resources to answer this question on its own but that the full genomic sequence results expected in the next decade be used to answer this and many other questions simultaneously.
I am certainly not a hero worshiper of Cochrane, in fact I think he's probably wrong on this one - most simplistic or 'obvious' solutions in human genetics turn out to be incorrect, but it is sad that PZ shows such a complete fail in his understanding of basic population genetics in this post.

Mary certainly doesn't sound like she cares to understand the issues or genetics. I mean, considering you can find the /geq "0.5" heritability figure in goddamned Wikipedia, it more or less confirms that she doesn't know the literature, BUT DON'T FORGET she is berry berry outwaged. There's even a link WITHIN THE COMMENTS kindly provided by Josh on IQ and heritability and IQ's neurobiological correlates, with all sorts of pretty graphs and brain diagrams, but Mary definitely had to spout off without researching a thing because everyone should know she really hates racism and eugenics and the Nazis.

Of course she is lying about researching Cochran's claims the whole week. I mean, if you search "Ashkenazi intelligence" in Google the first link you should find is that of ParaPundit and extra links continuing the speculation. Somewhere along the line any non-moron should have stumbled upon Lynn's work on IQ differences.

This is just another boring data point in the general trend. Not only do the outraged tend be innumerate and completely unfamiliar with any literature, they flaunt and shame themselves in their ignorance.

By ANONYMOUSE (not verified) on 22 Apr 2009 #permalink

@119

"Biological determinism has never, ever aided scientific research and i for one don't want to have to tackle that inane concept again."

False.

By Caleb Zhang (not verified) on 22 Apr 2009 #permalink

@ Eric Johnson (119)> great, you've pulled a quote and not bothered to consider the point it was part of... My point was conceding that there are cultural influences to those traits, as well as genetic, working together. I would consider epigenetic factors to be equally environmental and genetic, because without the environmental impact they don't, in fact, express. So if that's you're genetics comment, fair enough. But yes, you're being a pain :)

Mary>

I don't doubt that humans are still evolving, but setting up such divisions is eugenics, pure and simple. These are the exact scientific techniques that allowed the Nazi's to justify the Holocaust and Europeans to justify slavery, apartheid and colonialism - yet the early eugenicist's studies were never found to be been fruitful.

Biological determinism has never, ever aided scientific research and i for one don't want to have to tackle that inane concept again.

Allowing your sociopolitical convictions to influence your perception of science much?

Eugenics is "the study of, or belief in, the possibility of improving the qualities of the human species or a human population by such means as discouraging reproduction by persons having genetic defects or presumed to have inheritable undesirable traits (negative eugenics) or encouraging reproduction by persons presumed to have inheritable desirable traits (positive eugenics)."

Wiki

Nice slippery slope then, eh? Overblown use of such divisions could lead to eugenics, making such distinctions between people is called research. You're either extremely niave about it, genuinely biased by your view of "determinism is bad", or blowing smoke because you wanted to make your point. Based on the rest of your posts I'd wager a fair amount on the 2nd... Again with the offended liberal sensibilities: There are in fact things that predispose people towards personality traits (e.g. testosterone is a direct factor in promoting aggression, Ridley, The Red Queen, not looking up his source for you). You can choose to ignore that if you like, or you can accept the science that's there, with the corrolary that predisposition, which is what genetics do for personaility in sentient beings, is not the same thing as mandated action. There's your free will. You might re-read the end of The Selfish Gene , it makes exactly this point, and far more eloquently.
My only reasonable support for Cochrane on this stems from what I know of ecology and population genetics, which is actually my field. Attempts to claim that one source or another is solely responsible for a polygenetic trait like intelligence are fruitless, because the best we can hope for is to determine factors that influence that trait and attempt to gauge the level of influence and interactions of those factors. I don't personally give a rat's ass what you think of Cochrane personally, or Pinker, or the rest... what does concern me is that a) PZ misrepresents a good deal of the work in order to make his point, something I'd hope he'd not stoop to, and b)the fact that none of the objections raised by the synchophants above, save those of Tulse, are based on anything other than offended sentiment. I'm not telling anyone to shut up, provided they raise a real objection, or at least attempt to support what I wouldn't initially call one.

Eric> in support of my point:

The heritability of IQ is probably lower than 0.80 in most human populations, and it may
be as low as 0.50, so there are apparently some environmental effects on IQ.

taken from http://homepage.mac.com/harpend/.Public/AshkenaziIQ.jbiosocsci.pdf

ie, this paper itself. Again, not entirely either way.

From the conclusion of said paper:

Our general hypothesis is that high IQ test scores of Ashkenazim, along with their
unusual pattern of abilities, are a product of natural selection, stemming from their
occupation of an unusual social niche. All the required preconditions–low inward gene
flow and unusually high reproductive reward for certain cognitive skills, over a longenough
period–did exist. These preconditions are both necessary and sufficient, so such a
selective process would almost inevitably have this kind of result. The pattern of high
achievement among Ashkenazi Jews and the observed psychometric results are certainly
consistent with this hypothesis.
Our more specific prediction is that some or most of the characteristic Ashkenazi genetic
diseases are by-byproducts of this strong selection for IQ. In particular we think that this
is the most likely explanation of the sphingolipid mutations. The improbably high
frequency and observed effects of the storage compounds of axonal and dendritic growth
are very suggestive of selection for some neurological trait.

Hmm... where's the crank? Whoever wrote the article PZ reported on is being a bit dishonest, extending conclusions beyond those of the original paper. If Cochrane himself contributed to that, then he's out of line, but the paper itself is pretty sound.

Allowing your sociopolitical convictions to influence your perception of science much?

Although this comment isn't directed at me, I think it should be noted that arguably some folks on both sides of the evo-psych debate engage in supporting their own sociopolitical convictions.

There are, as I see it, stereotypes for two common narratives that arise when talking about this area. One is the extremely PC opponent, who is characterized as seeing evo-psych as dangerous, regardless of how true it is, and argue it threatens the values of equality and human dignity, regardless of whether its claims can be defended. But there is also the narrative of the other side, that of the brave iconoclasts who cannot be silenced by the forces of political correctness, and who are simply following the evidence wherever it may lead (even though it remarkably always leads to supporting common beliefs about race and gender). The thing is, neither narrative has anything to do with science. What is true may not be "politically correct", but also what is not "politically correct" is itself not automatically true. One has to do science to determine what is actually the case.

And for me, it is the science in evo-psych that seems to be so generally lacking (although this is not universally the case). Often claims are made on the flimsiest of evidential bases, or even without any evidence at all. In many cases, it seems sufficient merely to propose some vaguely plausible explanation in order to gain the attention of both the scientific community and the press. These Just-So stories are admittedly very interesting and appealing, but often they are just that, stories, without much support. I think it is extremely useful to contrast these "explanations" and their supporting evidence with those in ethology -- as I see it, very few of the "explanations" applied to human behaviour would be accepted as well-supported if they were instead about non-human animals.

In the end, it doesn't matter whether evo-psych tells us truths we like or not -- what matters is whether it actually tells us the truth. And to do that, it needs to do good science, unpacking the theories it proposes and their underlying assumptions, and providing quantitative data that speaks to those assumptions. As I see it, evo-psych rarely does this to a level that we should demand.

@Tulse> we come at this with exactly the same approach, with the exception that I am aware that even in ethology it isn't necessarily possible to have quantitative evidence for everything. Qualitative observation, if properly done, also carries weight in psych, ecology, ethology, etc. I fully agree that evo-psych needs to be held to the same standard that these are in order for the science to be valid.

that of the brave iconoclasts who cannot be silenced by the forces of political correctness, and who are simply following the evidence wherever it may lead (even though it remarkably always leads to supporting common beliefs about race and gender)

Hmm... who's doing this? examples? How does this differ from actual objectivity, if the evidence does lead to the common beliefs? From most of what I've seen, there're still important distinctions between what the evidence implies and what the old adages are. There very well may be people who are evangelising for evo-psych because they assume the PC view is wrong... I'm simply pointing out that the side I described is alive an kicking in this thread, and failing to give a reasonable perusal of the science behind the assumptions. Read the paper linked above, and decide for youself how the evidence falls. The conclusions of that paper aren't nearly as overblown as those in the LA Times article, which makes me suspect sensationalist media more than poor science.

Cochran and Harpending readily acknowledge the need for such experiments. But they have no plans to do them. They say their role as theorists is to generate hypotheses that others can test.

Oh really? So they didn't immediately think "hey, we can get a research grant out of this, hire some experimenters and tick some more boxes toward our next promotion?"

Because it sure as shit would have been the first thing that occurred to me.

Tulse, you are completely correct in your criticism of evo-psych here but I think you are misapplying a valid criticism of that field of research to a particular instance that doesn't deserve it.
Usually the problem is evo-psych researchers throw out a speculative hypothesis that so-and-so phenotype was selected for such-and-such reason - essentially an unfalsifiable situation because we usually don't know the specific genes available to examine. In this current case we do and could theoretically falsify the hypothesis. PZ was criticized for misrepresenting the work of Cochran and Harpending over the specific point of evidence for selection versus drift - an entirely separate point from whether Cochran and Harpending had the data to back up their hypothesis (something that even they admit is currently lacking).

How does this differ from actual objectivity, if the evidence does lead to the common beliefs?

It differs in that the proponents implicitly suggest that merely proposing uncomfortable claims somehow makes those claims more likely to be true. It's a rhetorical device similar to the common "they laughed at Newton!" gambit. And you see this very often in the discussions of race-based research, although admittedly usually not from the researchers themselves (then again, the "PC" argument also is rarely evoked by scientists who question such work).

In this current case we do and could theoretically falsify the hypothesis.

Right, and I guess my point is that we shouldn't make a big deal out of this speculation until it has been examined empirically, and all the underlying assumptions and possible counter-explanations have been looked at. I would contend that the only reason we are talking about this is because it resonates with some commonly-held stereotypes about the Jewish ethnicity -- if this were a similar claim about, say, the Romani, or Australian aborigines, it would not have received the attention it has.

"I would contend that the only reason we are talking about this is because it resonates with some commonly-held stereotypes about the Jewish ethnicity"
No, their paper has been out for a long time.
The only reason we are discussing it at length now is that PZ suddenly decided to label Cochran as a pseudoscientific crank and used a misrepresentation of their research to back up this ridiculous accusation.

Sigmund, I meant "we" in the broader sense, as in the LA Times article. My point is this kind of speculative research generally only reaches the popular consciousness when it seems to feed into commonly-held beliefs about well-known ethnicities (do you think the LA Time would have covered a similar story about, say the Innu?).

Tulse
And for me, it is the science in evo-psych that seems to be so generally lacking (although this is not universally the case). Often claims are made on the flimsiest of evidential bases, or even without any evidence at all. In many cases, it seems sufficient merely to propose some vaguely plausible explanation in order to gain the attention of both the scientific community and the press.

Very true, but is it not the blind "support of sociopolitical convictions" (from either side) which creates the buzz?
And there is no such thing as bad publicity, and "publish or perish", and...
I LOVE when the stupid monkeys clash and crash, I hope they all get "Darwinian rewards".
I guess I am a bit misanthropic...

latsot
Because it sure as shit would have been the first thing that occurred to me.

Sure as shit it did not occur to you to read the thread!

IST,
I was reading fast - it's possible I distorted your quote but I'm pretty sure I didn't.

I definitely agree that within-group heritability estimates for IQ range from 0.4 to 0.8, although I understand the heritability is generally higher as one reaches full adulthood. So there is no doubt that nongenetic factors influence IQ.

However, my point wasn't about causes of variation in IQ - my point was, people often note that ashkenazim highly value education, and want to use this to leave the door open to a possible primacy of culture as a cause of human traits; the irony is that traits like valuing education might well themselves be influenced by genes.

I do, definitely, agree that culture matters a great deal. I am no genetic determinist, since it seems like genetic control of variance in many traits that seem important is 0.4 to 0.7 - a long way from 1.0.

By Eric J. Johnson (not verified) on 22 Apr 2009 #permalink

Mary,

> This point sounds completely illogical to me.

I'm only saying that our minds often tend to intuit 100% free will in "cultural" traits like valuing education, but in fact variation in these traits could have a major genetic component. Just compare the variance in gentile white americans in how much they value education, to the variance in the same trait among the children of a single gentile white american family. The siblings all grew up in the same family environment yet the variance they show is likely to be pretty large compared to the variance of the whole white gentile american population, so it looks like genes and/or stochastic factors are likely to play a significant role.

Admittedly, it's harder to directly explore the origin of differences between ashkenazi americans and gentile white americans in value placed on education.

> Culture, learned, developed and evolved culture, has had a very real impact on society - to reduce its impact to naught because of a silly hypothesis is ludicrous!

The thing is, the "genetic determinist" who denies culture's importance doesn't really exist. So-called genetic determinists usually argue for around 50% control by genes of within-population variance in several important traits. This is miles and miles from predestination.

> I don't doubt that humans are still evolving, but setting up such divisions is eugenics, pure and simple. These are the exact scientific techniques that allowed the Nazi's to justify the Holocaust and Europeans to justify slavery, apartheid and colonialism - yet the early eugenicist's studies were never found to be been fruitful.

Actually, the nazis banned IQ tests, because they knew the ashkenazi outperformed gentile germans on average on these tests.

As for eugenics, well, I'm in favor of liberal eugenics. No, this doesn't mean sterilizing GOP voters :) ...I mean "liberal" in the political philosophy sense, the sense of the individualist "modern liberal-democratic" state. Eugenics doesn't necessarily have to include killing or sterilizing anyone, nor does it have to involve any state coercion or state incentives whatsoever. If the Tay-Sachs allele turns out to be worth 10 IQ points and you are having a baby and feel like splicing it into your embryo, I say "fine, do it." That's the eugenics I'm talking about.

As for it not being fair that ashkenazim are somewhat smarter *on average* - well, it's just too bad, and the fact is, it's *quite* unlikely that *none* of their average 12-pt IQ advantage is genetic, or that less than 15% of it is. I won't try to claim that this fact doesn't matter at all. It does, because human tendencies for tribal and group feelings are natural. But I will say that how smart you are and how smart I am as individuals is a good deal *more* important, and that has nothing to do with our group identities. Sometimes I'm a little jealous (OK, moderately jealous) of some jewish dude or other who's smarter than me. Say he's got about 12 IQ points on me, I'm apt to think, "dang, he's jewish though, so it doesn't *really* count; heck, I'd be that smart too if I was jewish." Of course this is complete nonsense. We simply are how we are, as individuals. Sure, if I had Isaac Newton's genome I'd be as smart as Newton (probably smarter, because the environment I experienced is probably more favorable). There are a zillion jews in the US with IQs lower than the average goy's.

> Can you please provide more information on this, for example:

- the sources
- the "few different personality traits have shown a heritability around 0.5 in studies"
- the "multiple convergent lines of evidence in favor of the theory"
- the different research groups you mention?

Wiki "big five personality traits," the descriptive analysis of personality which is the most highly regarded by most psychologists. It states with references that the heritabilities of the five traits range from 42% to 57%.

Judith Rich Harris' famous book apparently finds heritabilites of around 50% for a very large range of personality traits and life outcomes; this was work done by a variety of research groups. I think there are studies that disagree but she tended to find them severely wanting as far as their methodological logic. I haven't read her myself.

Then there's IQ -- that rather important social variable which correlates somewhat with income, job performance, etc -- and which probably has a heritability above 50%, assuming you look at people 20+ years old.

There are some traits with very low heritability - as I recall, violent crime in the US is one.

By Eric J. Johnson (not verified) on 22 Apr 2009 #permalink

Mary,

Oops, I forgot this one:

> the "multiple convergent lines of evidence in favor of the theory"

I'm going to plead fatigue on that; I don't want to rehearse the entire hypothesis especially when the paper itself is free here:

http://homepage.mac.com/harpend/.Public/AshkenaziIQ.jbiosocsci.pdf

This is just an incomplete sketch:

-If the unusual burden of genetic diseases in the ashkenazim is from inbreeding as Myers claims, why does Cochran find no increased homozygosity? Are there any empirical claims for evidence of inbreeding? I don't know. Myers certainly hasn't cited any; he only put it forward as an idea.

-Why do so many of the ashie diseases cluster in the sphingomyelin pathway when the vast bulk of the human genome has nothing to do with sphingomyelin?

-Why is there already some evidence that these alleles are associated with high IQ (Gaucher disease, torsion dystonia)?

-Why do no classical authors extol the jewish intellect despite their total disinhibition about mentioning group differences (for example, Aristotle opined that the greeks deserved to rule the world because of their higher average rationality)?

-Why are there multiple different Tay-Sachs alleles that have risen to high frequency in the ashies despite causing disease (see above in this thread)? This is not consistent with drift/bottleneck/inbreeding.

By Eric J. Johnson (not verified) on 22 Apr 2009 #permalink

"I would not be offended by [a different theory]...there is also no tendency by a benign nature to balance every individual's shortcomings with a beneficial mutation."

Luckily, a benign nature keeps anything that offends PC Myers from being true.

Jesus christ. You are a creationist, nothing more. Racial groups sepearted by over 50,000 years of evolutionary history magically evolved the exact same? Please.

Astonishing stuff PZ. You are on the wrong side of history, leftist politics imposes itself on your science, quite pathetic.

By Sebastian (not verified) on 22 Apr 2009 #permalink

I cannot believe you invoked creationism yourself! It's so funny. Which of these is more creationist:

Groups seperated by geography, climate, wildly divergent selection pressures and 50,000 years of evolutionary history have evolved to the present moment in markedly different ways - whether it be in terms of skin colour, testosterone levels, sexual strategies, and general intelligence

OR

50,000 years ago evolution stopped working because that's when the god of politics intervened and said that evolution is only right if it means everyones equal and the same and the world is full of lollypops and gumtrees.

By Sebastian (not verified) on 22 Apr 2009 #permalink

"PC Myers"

I hope that will stick, LOL

Thanks Eric J. Johnson and Sigmund

Thats the type of information I was looking for and props to you for answering my questions.

I have been trying to research this topic all week and many comments here and on other sites replying to me (and many others with reasonable questions) were part and parcel of this over zealous Cochrane fan club that has sprung up.

A gentle hint for the future to those Cochranites who have infested this thread - when someone has doubts about your views and asks questions and for sources, try to engage/ provide info rather than rattle off a list of inane trollish comments and one word answers - that is, if you are actually interested in people outside your 'inner circle' understanding your views - my guess is that unfortunately most of you aren't.

Anon, I think it did stick. I stole it from somewhere.

Mary, you haven't done enough research to get Cochran's name right. Wonder if you got other stuff wrong as well.

Eric> You misread it, but most likely because I'm never going to win a contest for brevity. We basically agree on all points here.

Mary> You would be likely to get more patient answers if you used something resembling logic in your attacks, you received trollish answers in response to a trollish lead in. I sincerely doubt anyone involved, including you, was sinmply doing that. I did answer your post with far more than one line, including references for you, although not in a manner you were likely to appreciate. As I stated above, your opinions of Cochrane and Pinker aren't my concern (I hadn't, in fact, heard of Cochrane before this post), but the gross logical errors you made in your post weren't going to be given a pass, nor would I expect my own to be given one.