For anyone around Bloomington, there’s a symposium Human Brain Evolving, this Friday and Saturday. You can see the abstracts online. Looks like Bruce Lahn will be there. If anyone wants to send me a “report” after attending just use the contact drop down to the right and I might post it.

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A few weeks ago, Andrew Brown (author of The Darwin Wars) stated:

I’m not sure that Boyer, Atran and Wilson regard their explanations as complementary. I have talked to all three of them about it. My feeling is that while all three of them understand that the explanations might be complementary, they prefer to believe that all the work is done by their preferred model. It’s not clear to me how one could decide this point in principle.

He refers to Scott Atran (In Gods We Trust), Pascal Boyer (Religion Explained) and David S. Wilson (Darwin’s Cathedral). Atran & Boyer are of very similar intellectual outlook, they’re cognitive anthropologists who synthesize psychological and evolutionary paradigms and apply them to anthropological questions. They were both part of Dan Sperber’s salon during the early 1980s in Paris, and work within a ‘naturalistic’ tradition of their discipline which attempts to decompose & reduce anthropological phenomena to make them analytically tractable. In contrast, David S. Wilson in Darwin’s Cathedral is by training an evolutionary biologist who ventures frequently into anthropological territory. All three overlap insofar as they employ methods from a range of fields to explore human social and anthropological questions, though Atran and Boyer emphasize psychology far more than Wilson. In my comments & posts on this weblog I’ve contended that these two models actually are complementary and analyze different levels of religion as a natural phenomenon.

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PNAS has a paper titled Growth, innovation, scaling, and the pace of life in cities, which notes that a majority of humans now live in cities. I know that historically cities were a population sink (and only a small minority ever did live in cities), but, I have to wonder what evolutionary implications the normativeness of city life will have on our species over the next few hundred years (assuming some sort of collapse or explosion doesn’t make the idea of humanity irrelevant)? I say this because I suspect that the transition from hunter-gatherer to “dense” village living was highly significant (as illustrated by the mass disease die off in the New World when exposed to the Eurasian pathogen pool). Robin Dunbar’s work suggests that our cognitive social intelligence doesn’t scale up much past around 200 individuals. Villages aren’t necessarily that much more populous than this, but cities are.

Chris of Mixing Memory rips into the usual suspects for analogizing atheist activism with the women’s suffrage movement. I have basically taken a sabbatical from these SB intramural debates about religion, Creationism, etc. So I’ll let you comment over there. But, I will offer that I’ve never been jumped for being an atheist, but I have for being a “sand nigger.” So I hope people will maintain some perspective….
Update: Also @ Mike’s & Josh’s.

To all those with some familiarity with psycholinguistics, what do you think about The New Yorker by John Colapinto, The puzzling language of an Amazon tribe? What are the best commentaries on this thesis? My interest has been piqued, but I’d like to know more (here’s an article on the tribe in question, and check out the wiki entries).

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We previously reported that a measure of school achievement built from national test scores has a nearly perfect correlation with national IQ (at least in the range of scores tested). Subsequently, Lynn et al. (in press) published a very similar analysis:

This paper examines the relationship of the national IQs reported by Lynn & Vanhanen (2002, 2006) to national achievement in mathematics and science among 8th graders in 67 countries. The correlation between the two is 0.92 and is interpreted as establishing the validity of the national IQs. The correlation is so high that national IQs and educational achievement appear to be measures of the same construct. National differences in educational achievement are greater than differences in IQ, suggesting an amplifier effect such that national differences in IQs amplify differences in educational achievement. Controlling for national differences in IQ, slight inverse relationships of educational achievement are observed with political freedom, subjective well-being, income inequality, and GDP. However, public expenditure on education (as % of GDP) was not a significant predictor of differences in educational achievement.

The IQ’s Corner blog has an interesting note about forthcoming commentary.

On a related note, recall that Templer & Arikawa (2006) reported a near perfect environmental correlation between national skin color and national IQ for old-world countries. An unfortunately confused commentary by Hunt & Sternberg accompanied the publication. They wrote: “We argue that the report by Templer and Arikawa contains misleading conclusions and is based upon faulty collection and analysis of data. The report fails to hold up for quality of data, statistical analysis, and the logic of science.” The criticisms by Hunt & Sternberg are based largely on a misreading of Templer & Arikawa’s methods, particularly the method for deriving national skin color values.

A paper published in 2000 by Jablonski & Chaplin (“The evolution of human skin coloration”) can more directly address these criticisms. Jablonski & Chaplin published a table of skin color reflectance values from many old world populations (Table 6, also see the appendix). I very crudely averaged values from the same country to make a new measure of national skin color. This measure of national skin color correlates with the skin color index of Templer & Arikawa at r=-.91 (the negative is not important here). The reflectance measure of skin color correlates with national IQ at r=.87. The school achievement measure of Lynn et al. correlates r=-.79 with the skin color index of Templer & Arikawa and r=.75 with the skin color reflectance values crudely averaged from Jablonski & Chaplin. Thus, the skin color values derived by Templer & Arikawa are well validated by an external data source and the national IQ-skin color relationship is found to be robust across two measures of national IQ and two measures of national skin color.

Note that there are substantially more missing values in the school achievement and skin reflectance data sets (no imputation of missing values) with missing values skewed towards lower values of national IQ/school achievement and darker skin colors. Also note that the blind averaging use on the skin reflectance data most likely attenuates the correlations.

Templer & Arikawa had two abstracts at the 2006 ISIR conference, which provide additional support for the validity of the measures and their relationships:

source

Correlations of Skin Color and Continent with IQ
Donald I. Templer & Hiroko Arikawa

The present study determined (1) the correlations between skin color and IQ across the countries of three different continents; and (2) the correlations of both skin color and continent in the three pair combinations with the three continents. The product-moment correlations between IQ and skin color were -.86 across the 48 African countries, -.55 across the 48 Asian countries, and -.63 across the European countries. When the 96 countries of Africa and Asia were combined skin color correlated -.86 and continent correlated .75 with IQ. The respective correlations were -.97 and .89 across the 81 countries of Asia and Europe, and -.71 and .54 across the 81 countries of Europe and Asia. In multiple regression continent yielded minimal increment to skin color in predicting IQ. In an earlier study (Templer & Arikawa, 2006a) skin color correlated more highly with IQ than racial category, but racial category yielded greater increments in multiple regression than did continent in the present study. The present findings, combined with previous research relating skin color and IQ (Templer & Arikawa, 2006a; 2006b), indicate that skin color is a robust correlate of IQ in an international perspective.

Empirical Support for Rushton’s K Differential Theory
Donald I. Templer & Hiroko Arikawa

The purpose of the present study was to empirically substantiate Rushton’s Differential K Theory that purports that groups of persons with K (in contrast to r) characteristics have a life history and reproductive strategy that includes higher intelligence, less reproduction, less sexual activity, better care of offspring, lower birth rates, greater life expectancy, better impulse control, and greater social organization. The present research intercorrelated national mean IQ, infant mortality, HIV/AIDS rates, birth rates, prevalence rates, and life expectancy in 129 countries in Africa, Asia and Europe. All of the correlations were substantial and in the expected direction. Also supportive of Rushton’s theory is that there was only one factor which accounted for 75% of the variance and was labeled “K-r continuum.” All five variables were correlated with an economic variable (per capita income) and a biological variable (skin color, which correlated highly with intelligence in previous research). Skin color correlated more highly with all five variables than per capita income so as to support the contention of Rushton that this continuum is biologically based. Factor analysis with all seven variables yielded one factor that accounted for 73% of the variance.

Jason Malloy adds: Templer & Arikawa’s research follows Lynn and Rushton in arguing that cold temperatures were a significant force in the evolution of human race differences in intelligence. I have stated some problems I find with this hypothesis here, although it is also largely consistent with the geographic distribution of global populations by IQ. A recent analysis by blogger Audacious Epigone adds yet another revealing data point to this association.

Latitude (and hence colder climate) is associated with IQ not only cross-nationally (.67) but within the US as well. AE found a correlation of .70 between his measure of state IQ and the latitude of the most populous city in each of the 50 states. Furthermore intelligence is associated with latitude equally for both US whites and blacks (.52 and .51).

It’s not immediately apparent if and how this association is genetic or environmental. Either way it seems fair to seriously consider that global warming will provide yet another detrimental negative pressure on the intelligence of human populations in the coming decades.

Recently I stumbled upon this story, Speeding HIV’s Deadly Spread: Multiple, Concurrent Partners Drive Disease in Southern Africa, via Radio Open Source. The important point is that one of the major variables in the spread of HIV in Sub-Saharan Africa is the nature of sexual networks (it shouldn’t be too hard to imagine that social network theory models this well). From the article:

Researchers increasingly attribute the resilience of HIV in Botswana — and in southern Africa generally — to the high incidence of multiple sexual relationships. Europeans and Americans often have more partners over their lives, studies show, but sub-Saharan Africans average more at the same time.
…
…Husbands spent months herding cattle while their wives, staying elsewhere, tended crops, Mosojane said. On his return, a husband was not to be quizzed about his activities while he was away. He also was supposed to spend his first night back in an uncle’s house, giving his wife time to send off boyfriends.

Steve Sailer has long been emphasizing the low paternal investment that African males engage in as part of the problem. Without a consistent and reliable single male to supplement her own economic productivity (in much of Africa women were the primary agricultural producers) it seems that it would be rational to “diversify” one’s portfolio. This is obviously not the only issue, the variation in HIV infection rates across the continent which track circumcision rates show that the dense sexual networks facilitate the spread of the virus at different rates depending upon the nature of the “choke points” (so to speak).

Note: The report suggests that circumcision was discouraged by European colonial missionaries in southern Africa. I’m skeptical of this for several reasons. First, during much of the colonial period circumcision was the norm in England, which was the dominant power in this region. Second, colonial influence seemed to be irrelevant in most of east & west Africa, where the rates of the practice follow traditional patterns. There is one group in Kenya that does not practice circumcision (unless, I assume, they are culturally Muslim, such as Barak Obama’s father), the Luo. Is it because they were less colonized than other ethnic groups? I doubt it. Finally, I am to understand that Zulus circumcision specifically ended due to the command of the warlord Shaka. This predated colonization or missionaries. So, I think it is important not to take all the contentions in the article without a grain of salt since the reporter is obviously dependent on sources who will tell him whatever they want (i.e., I think the idea that circumcision was discouraged by whites is probably plausible because of the dominance of Post-Colonial theory which makes Europeans gods who have ultimate power over the direction of all the world’s cultures).

Doing dissections is boring. Learning about international politics while doing dissections is less boring. Hence, I recommend checking about the Carnegie Council for Ethics in International Affairs podcast. Here’s a list of more educational podcasts from Big Monkey, Helpy Chalk, including a conference on Neural Correlates of Consciousness.

On a less nerdy tip, these mixes by siik are dope. And the Mixtape Show… Wack Shit – Not Allowed. Ever.