August 2011


It’s too bad he doesn’t regularly blog at some fixed spot, I never would have known about this post at the Straight Dope forums if it hadn’t been mentioned in a comment at GNXP classic. It’s about his famous paper with Henry Harpending on the natural history of Ashkenazi IQ. I recall it being rather favorably received by the press (I believe it was a Newsweek cover, and Steve Pinker gave a popular talk), but by Cochran’s account a lot of academics wouldn’t touch it with a ten-foot pole.

Steve Hsu’s Google Tech Talk on the BGI IQ study is here. BGI was one of the organizations that turned down Cochran & Harpending*.
*I gave an inaccurate account. See Henry Harpending’s comment below.

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SG showed up in the comments to link to his blog. I responded to his specific concern, but elsewhere I found this amusing. Lawrence Auster was complaining about “drinking publicly from water bottles”. Is it a Leon Kass licking ice-cream thing? I suppose I am too young to remember a time when it was “unacceptably rude or low-class” rather than the mark of a yuppie who think he’s too good for tap-water. He also says “Western liberal people have become obsessed with having a constant supply of fluids. The idea must have spread among the politically correct that if you are not imbibing water every minute throughout the day, your free radicals might make you age prematurely or you’d get some dread disease.” That’s a completely separate issue from whether you drink water from a bottle or glass on CSPAN though.

Like SG I have a metal bottle (made in China!) I got from work, though I don’t carry it around and don’t feel like going into why I don’t use cups at home. Growing up my family did eventually purchase some plastic bottles, but we made sure to keep them around so they could be filled from the tap, at least until a dog chewed them up and a replacement was needed.

William McNeill’s “Plagues and Peoples” seems like an interesting enough book, but for some reason I haven’t spent much more time reading it since the last post on it. Still, there are some things I should have mentioned then and forgot to, and a few additional notes from later on.

I came to this book on disease with a mind primed by Ewald & Cochran. Paul Ewald in particular in his book “Plague Time” rails against a theory that disease inevitably adapts itself to host populations, approaching symbiosis in the limit. Instead he points out that disease only needs you to survive long enough to make it to the next host, and otherwise views you as a resource-laden factory to be used up and thrown away. McNeil is one of those people who assumes the old theory. To him virulence is evidence that a disease is new. Particularly dangerous diseases are those with multiple hosts, and he thinks that’s because the disease had spent all that evolutionary time adapting to an older host and only recently made the leap over. “New Germ Theory” would argue instead that hosts like mosquitoes make diseases less reliant on healthy humans, thus reducing the cost of virulence.

McNeill does present some examples for his argument. One concerns a disease that was found among Brazilian rabbits called myxomatosis, which had a stable pattern of mild symptoms. It was deliberately introduced to the Australian rabbit infestation (which belongs to a different genus than New World rabbits) and had an initial fatality rate of 99.8 percent. Rabbit generation time being what it is, it didn’t take that long (in human terms) for the progressively milder symptoms to reach a steady state with a smaller rabbit population. In Canadian Indians, tuberculosis initially affected parts of the body unaffected among European settlers. After three generations it morphed to the familiar pattern of remaining in the lungs.

An entirely different point McNeill makes is that having fields like fallow has nothing to do with “replenishing soil”. Since I read the textbooks he derides when I was in school, that was news to me. He allows exceptions for “dry farming” where it is desirable that moisture be retained in the field, but otherwise regards any chemical changes as insignificant. Instead, “the great advantage of fallowing is that it allows farmers to keep weeds at bay by interrupting their natural life cycle with the plow”. I still don’t entirely get the logic behind that and the three-field system, but I’m not a farmer.

McNeill is at his most Jared Diamond-ish (really, I should say, Diamond is at his most William McNeill-ish) when he argues that civilization did not expand due to its attractions, but its disease advantage. He does allow though that sometimes uncivilized people had dangerous enough infections to stand their ground against the urbanites/farmers. He offers India as “a sort of test case”, where a civilization established cities in the relatively dry northwest, and after recovering from the Aryan invasion expanded to the point where it came into contact with “forest people” of the more tropical south. Here an “epidemiological standoff” ensued in which each side was vulnerable to the other. So instead of being virtually obliterated (like inhabitants of the New World) they were gradually incorporated as new castes, maintaining many old rites up to the modern era. McNeill displays a Marvin Harris-like functionalist attitude toward cultures, and so he interprets Hindu caste taboos as defenses against infection by vulnerable communities. This functionalism falls on its face occasionally, such as when he acknowledges rituals of ablution can actually encourage infection and that some mosques were found to have pools of water full of snails infected with schistosomiasis.

UPDATE: Reading further, McNeill claims that cities would have reached stability to the “childhood disease” point and so historical epidemics would have been characteristic of outlying regions. I could not refrain from rolling my eyes and laughing at him. Not that I know if there were more epidemics in those regions (of which we have fewer records) or cities, but he is downplaying an urban disease problem that is pervasive throughout urban history and my priors are heavily weighted on the opposite side of the scale.

UPDATE 2: A few more surprising claims. I had been taught that one of the few diseases to flow back from America to Europe was syphilis. McNeill acknowledges that there are no recorded cases of syphilis in pre-Columbian Europe, but thinks the disease just happened to evolve around that time. There was a leprosy-like disease called yaws which apparently spread through a spirochete identical to syphilis, but was both milder and widespread (rather than just among adults). Yaws declined in the later medieval years, and McNeill thinks that the increased use of clothing and decreasing use of huddling to survive the cold (except in Scandinavia) forced yaws to evolve into syphilis. Aside from leprosy, cold northern areas seem less afflicted by disease, and McNeill attributes the greater mysticism and ritual of Catholicism (in comparison to Protestantism) as a response to the greater inexplicable outbreak of epidemics in more southern areas. He also says that based on some sayings of Muhammad, Muslims took a much more passive approach to disease. This was surprising to me, since I’d heard that the Ottomans were using inoculation before Louis Pasteur was around. He argues that the disease toll on Muslim conquerors is what enabled the Christian populace of the Balkans to regain independence.

I first heard about the new study on genetics & IQ from Steve, but a more comprehensive discussion is found at a different Steve. The lead author is Ian Deary, who has a surprisingly long list of publications. I expected a study along these lines to come out based on an earlier study on height I heard about from Jason Malloy. Look at a lot of genes for a lot of people and find out how genetic distance correlates with the trait in question. It doesn’t tell you which genes are the relevant ones, but that’s asking for a lot considering how many prior failures there have been. The view of the authors and most reporting on it is that it shows there are many, many, many genes each having a small effect on intelligence (as opposed to a smaller number of rare genes of larger effect, which would be similarly difficult to find). This is what you’d expect for a normally (or close to it) distributed trait like height. When I first mention it to Kevin Mitchell at GNXP classic he dissented, saying they failed to establish the polygenic nature of the trait. He has yet to make a post of his own, but he elaborated on why he disagrees with the authors in a comment at GNXP Discover.

On a completely unrelated note, Bill Woolsey is no longer mayor, as the South Carolina Supreme Court overturned (for the third time) the incorporation of the town of James Island. Fourth time’s a charm.

Alex Tabarrok’s paper was referenced in the wake of the recent London riots by his co-blogger, who provided a gated link. I found a non-gated copy here (missing a bunch of equations), but since I’m not sure how stable that will be I reproduce the text (with some symbols and sub/superscripts replaced) below the fold. (more…)

A comedy writer (presumably daughter of Shelby Steele) at Salon has an article at Salon about her inherited opposition to affirmative action being reaffirmed by her failure to get a Hollywood gig based on her (not physically apparent) background rather than talent. Although the various different cultures combined in her family have the potential for comedic situations, I was struck by the lack of humor in her article. How do you expect to get a comedy job unless you constantly signal comedic abilities in all your signed output?

Since she mentions her appearance, a google image search led me to this pic.

Anti-Managerialist Christ Dillow is curious, are neoliberal economists’ predictions about the effect of taxation on workers’ attitudes self fulfilling prophecies? Given a sea change in belief systems, will people behave more like the “new social(democratic)ist man?” Without providing any data either way – and I won’t either – he speculates that such attitudes are malleable and that talk of incentives in a market context are taken for granted by “boneheaded right wingers.”

I commented, writing that even assuming people held beliefs about taxation that didn’t entitle them to “higher than average wages,” IIRC most Americans believe themselves to be solidly middle class, even when their income would place them below, or above, the average. In this case beliefs about paying your “fair share” may already maintain, contra neoliberalism allegedly conning Americans into believing one is due their marginal productivity regardless of their place on the totem pole once income is accrued; it’s just that nobody believes themselves wealthy enough to be morally obligated to fork over their earnings for the greater good of equality. Everyone thinks they already do earn average wages/salaries. And those remaining, the uber-rich that know what a big deal they are, aren’t numerous enough to carry the full burden of equalizing outcomes (because at that level of taxation my hunch is that the disincentive effect is likely to kick in regardless of popular belief systems).

Given the above, the biggest impediment to greater equality would be the lack of popular knowledge of the income distribution, not right wing economic theory.

In any case, there are good reasons to support neoliberal belief (generally speaking) in market competition and civil society that have nothing to do with notions of incentives and just desert for rugged individuals, but this takes us into the post-libertarian emphasis on voice vs. exit, radical uncertainty, and other ideas you can read about here and elsewhere.

Over the weekend I picked up William McNeill’s “Plagues and Peoples”. I’ve already read an updated version of some of the same ideas in GS&S, but Razib has mentioned some facts in the 70s classic which were new to me, and I hoped there would be more. Plus, it’s unconscionable for Matthew Yglesias to know any science I don’t (Copernican Revolution, your day will come!)

In addition to diseases transmitted by flies, fleas and lice, McNeil mentions schistosomiasis as being transmitted by snails. I had never heard of that disease before, or known that there are any snail-borne human diseases. But checking that out on wikipedia, it seems the snails are more analogous to rats in that they carry a multicellular parasite.

Later on he says that herds of ungulates survived in Africa because the sleeping sickness carried by tsetse flies (which follow the herds) drove humans away. That seems strange to me because there are cattle-herders in Africa, and that may not have occurred until relatively recently (less than 10,000 years), I still don’t think the early herders had any defenses against the flies or disease. Cattle themselves may be an import from elsewhere, but I don’t think they repel flies any more than the more indigenous herds.

McNeill depicts humanity as arising in a hot, humid region with ferocious microparasite competition and then moving onto colder, drier regions where game animals were easier prey (not having evolved alongside anatomically modern humans and developed defenses). Then he makes the point that before the age of microscopes and antibiotics, human intelligence had little ability to deal with invisible microparasites. Jared Diamond used that logic to suggest that his New Guinean friends should be more intelligent than the dominant Eurasian civilized people who faced more disease than homicide. McNeill suggests something like Rushton’s theory in which colder climates put more selection pressure on intelligence rather than disease resistance.

He also says that since warm, wet climates are more natural for humans, those who crossed over the Bering Strait were kept at an equilibrium with their game but on moving south to easier climes large game was wiped out. I was going to point out the llama’s of South America as an exception, but they live up in cold dry mountain regions.