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June 26, 2004
PTC taste, balancing selection?
Long-time readers of the blog might know I have an interest in the genetics of taste. Here is an old post where I explore the question of whether variance in PTC-taster/non-taster frequency cross-culturally (that is, by population) might have a relationship to preference for spicy foods. The authors in the 1998 paper which I reference above note that:
I tried to connect the fact that South Asians have the highest frequency of non-tasters regionally with the observation that they also traditionally consume spicy dishes. This was prompted by an article which correlated latitude/climate with how spicy local dishes were. The authors noted that there is often a strong antibacterial effect that comes with the inclusion of spices, and this might have strong fitness consequences in tropical climates, and less at higher latitudes where the pathogenic environment is less stringent. I really didn't get far, and gave up on this line of thought after Abiola noted that some West African cuisine was extremely spicy, the population with the lowest percentage of non-tasters.
But, I did not highlight that there were other correlations between various tastes and PTC/PROP status. From the paper cited above:
So the key points from the above article(s):
1) Non-taster and taster individuals exist in all populations.
2) The frequency of the two groups seems to vary by population, sometimes to a rather large extent.
3) Non-taster and taster status have clear implications for one's perception of the taste of a wide range of foods.
4) Certain consumption patterns have clear relative fitness implications.
It was suggested in the paper above that PTC-PROP status is determined by a few genes, perhaps one primary locus and a secondary locus, and there could be more than two alleles at each locus. If the data on West Africa is correct, it seems that the alleles for non-taste exist at a rather low frequency, while in India, the alleles for non-taste exist at rather higher frequencies. I could offer a guess that perhaps India's history of elite vegetarianism meant that individuals who had fewer aversions to various vegetables had an advantage as far as nutrition went (in this case, there should be a positive correlation between the frequency of non-tasters and groups which have traditionally practiced vegetarianism, Jains, high caste Hindus and South Indians). Taking into account the issues with iodine deficiency and aversion to vegetables that might exacerbate this problem, there might also be a reason that people in certain regions are tasters.
Of course, they are examining the "PTC gene" that was found recently. The previous authors had less information to go on, and hypothesized multiple genes. I'll have to do some digging on this, but even the summary over at Science Blog (much more readable than the abstract!) notes that there are 24 genes that effect the taste of bitter. The fact that the authors found no great regional variations in the PTC gene, but previous authors have noted variations in the phenotype, suggests to me there must be other genes at work here even in the specific case of PTC taste. I don't have access to the full paper, so if readers who do can clue me/us in to details I might have missed, that would be appreciated.
 This test is often given in high school biology courses using a piece of paper that has been covered with the chemical in question. Students are asked to put the paper on one's tongue, and tasters immediately react with disgust, while non-tasters tend to be oblivious.
UK Immigration Data
The (UK) Office for National Statistics this week published data on immigration to the UK in 2001. (Go here and follow the links from the top news item.) Currently just over 1 in 12 (8.3%) of UK residents were born elsewhere. (This presumably doesn't include those smuggled in, who are kinda difficult to count.)
Contrary to some impressions, more than half of these immigrants are 'white'. But white immigrants (from Europe, North America, or Australasia), tend not to stay in the UK permanently - see the interesting article in Population Trends.
BTW, is it just my fancy, or has the ONS website improved hugely over the last year?
The Nuer Conquest
I have recently been trying to catch up with the literature on ‘cultural evolution’, and I hope to do a general survey of the subject - eventually.
Meanwhile, I noticed that one point came up repeatedly. Whenever writers on the subject want to show cultural traits spreading as a result of competition between groups, one of the key examples (if not the only example), is the spread of the Nuer people of the Sudan in the 19th century.
The odd thing about this is that not much is known about the Nuer in the 19th century. Evans-Pritchard’s classic book on the Nuer begins by listing the Victorian explorers’ accounts, but says ‘I have not been able to make much use of their writings, however, for their contact with the Nuer was slight and the impressions they recorded were superficial, and sometimes spurious’.
The prospects for a reliable account of the 19th century Nuer are poor. So why are so many writers on cultural evolution so keen on them?
The fashion seems to have started with Elliott Sober and D. S. Wilson’s 1998 book Unto Others. Sober and Wilson prominently featured a book by Raymond C. Kelly on The Nuer Conquest (1985). Kelly argues that the spread of the Nuer at the expense of neighbouring tribes (especially the Dinka) can be explained by the larger size of their raiding parties. This in turn depends on the Nuer tribal organisation, which depends on their lineage system, which ultimately is determined by their brideprice requirements, which are more demanding than those of other Nilotic peoples. As a result of their greater military effectiveness, the Nuer extended their territory throughout the 19th century, and absorbed several Dinka tribes who adopted Nuer customs. We therefore seem to have a good example of a cultural trait (Nuer brideprice) leading indirectly to its own competitive success.
No wonder this is attractive to advocates of ‘cultural evolution by group selection’, but is it true?
To find out, I went back to the source: Kelly’s book.
First, I have no major criticism of Kelly. His book is scholarly and well-argued (up to a point), and his thesis may even be true. He is not responsible for the use made of it by others.
What is reprehensible is the way that other writers, beginning with Sober and Wilson, have presented a highly speculative hypothesis as if it were a proven fact. My main objections are:
a. As already mentioned, little is known about the 19th century Nuer. We have less first-hand reporting on them than we do on Merovingian France or early Anglo-Saxon England.
b. Kelly’s argument involves a long chain of inferences. Like all such arguments, unless each step of inference is firm, the final conclusion is only weakly supported.
c. The argument also depends on the exclusion of rival hypotheses, and the rigour with which this is done. Kelly does deal with some previous hypotheses, such as ‘population pressure’, but it is not clear that he has considered all the alternatives. I subsequently discovered that there are other rival theories which he does not discuss.
d. In such a technical field much weight must be given to the verdict of experts. I have found two reviews of Kelly’s book. One, in American Anthropologist, is short and enthusiastic, but not by a Nuer specialist; the other, in Africa, by a French Nuer expert, is longer and more sceptical. (I could not find a review in Man, the journal of the (British) Royal Anthropological Institute.) There is also a long book by Sharon Hutchinson, Nuer Dilemmas, which merely mentions Kelly’s book among a dozen or so hypotheses on the reasons for Nuer expansion. Wendy James, another Nuer expert, in her introduction to the 1990 reissue of Evans-Pritchard’s Kinship and Marriage among the Nuer, surveys recent work on the Nuer but does not even mention Kelly. It seems fair to conclude that Nuer experts have not unanimously accepted Kelly’s thesis.
e. Finally, Kelly does not explain the underlying difference in brideprice practices itself, and it seems logically possible that he has put the cart before the horse: that the Nuer have heavier brideprice requirements because they are militarily strong (and therefore find it easy to raid cattle from neighbouring tribes), and not vice versa. The limited available evidence may not be sufficient to resolve the issue of causal priority.
But my concern is not to argue whether Kelly’s thesis is right or wrong, but to point out that it should not be presented as an unquestioned fact.
June 24, 2004
The Great Khan's brood
Bryan Sykes is talking about the descendents of Genghis Khan (Temujin) again. It seems ~8% of men in a broad swath of Central Asia are direct patrilineal descendents of the World Conqueror (or his father or grandfather, that is, his near relatives). Here is a test being sold by Sykes' company to see if you are of the Khan Y lineage. But remember, we are talking about the direct male line, this doesn't take into account all the Khan's daughters and their descendents, and the daughters of his male descendents! Here is a quote sometimes attributed to Genghis Khan:
Who "benefits" from affirmative action at elite universities?
Abiola has a entry where he references this article that discusses the fact that the proportion of blacks at elite universities who are immigrants or the children of immigrants (that is, usually West Indian or African in origin) is far greater than their numbers would suggest. Here is a telling quotation:
As I noted a week ago, those who are most able to utilize a system meant to redress past injustice might not be exactly who you would expect. The above article also highlights another major issue: those on the outside are prone to ignoring substructure within any given ethnic typology (and the "leaders" within any given ethnic typology are happy to gloss over substructure because it might create fissures in their power structure). Another example is the "Model Minority" paradigm of Asian Americans, which "activists" like to point out neglects the fact that Southeast Asians tend to be far less affluent than East and South Asians (and then tend to over-emphasize the Southeast Asian experience as if it is typical of Asian Americans). The success of West Indians in higher education should be no surprise to anyone, John McWhorter's Losing the Race spent a fair amount of time on this topic. The prominence of peoples of West Indian origin, from Marcus Garvey to Colin Powell, should also clue in any students of history on the disproportionate role this group has played in black America (along with mixed-race individuals and descendents of "free blacks," that is, those who were not slaves before emancipation).
School administrators almost certainly know that many of their African Americans students are atypical of the general African American population. To get into an elite university, one has to be academically atypical, and one would not be surprised if there was a skew toward higher incomes. On the other hand, it is peculiar that a particular ethnic segment of a given ethnic group tend to "fill up all the slots" that were probably intended to have broad-based utilization. But of course, administrators don't care, a West Indian African American looks the same in the brochures as an African American with roots in the "Black Belt" of the deep South. The bottom line is a certain number of African Americans in a university's freshmen class bolsters its "diversity" and keeps race warriors off the backs of university presidents .
Policies like race-based affirmative action were formulated in the 1960s, and they were most appropriate to the nation at the time. That is, one in which 90% of the population is formed by native born whites, and the 10% "minority" is coterminous with the native black American population. We now live in a different nation, but policies formulated for the "Old America" have become so entrenched that they are now fixed signposts that define the "rules of the game" in American culture.
Addendum: New readers might also be interested in this old entry about the individual impact of affirmative action on highly qualified black Americans. I conclude that though affirmative might be a net positive for the economic and social well being of American blacks, a highly qualified subset suffers because there is the perception that their success is not due to their talent, but rather, a "helping hand."
 In Mexifornia Vic Hanson refers to the practice of some universities recruiting Iberian Spaniards to bolster the number of "Latinos." Vanderbilt's outreach toward Jews is a way that the school can 1) bolster diversity and 2) increase its standardized test scores. One might imagine a university in the future recruiting highly qualified African students to bolster its percentage of blacks, without having to take the responsibilities of remedial education that institutions like CUNY have had to take on because of a push toward diversity.
Just to say I have been unavoidably offline for the past week, as my computer broke down. Since it was about 8 years old, not too surprising. I now have a new one, which takes up about half the space, is at least 20 times as powerful, and cost half as much, even without adjusting for inflation. So the world may be going to the dogs, but I must admit some things are getting better.
Thanks for all the many comments on my post 'We need a word'. I quite like the suggestion of 'patrophobia', but may the fittest word survive!
June 23, 2004
Is the day of the desi over before it began?
The The Indian American Society for Political Awareness states that "their mission is to increase political awareness in the Indian American community and encourage participation by the Indian American community in the American democracy." Over the past year I've had a friendly correspondence with other young South Asian Americans (as I am technically a "Bangladeshi American," not an Indian American) about the issue of the coalescence of desi identity. Recently I stumbled on to this article which chronicles interracial relationships among "Asian Americans." For Asian Indians, 5.8% of men are married to white females, while 4.0% of women are married to white males. But, when you extract U.S. born and 1.5 generation (born abroad, raised in the U.S., like me) Asian Indians out of these numbers, you note that 34.9% of men are married to white women and 27% of women are married to white men. When you look at the percentage of U.S. Born + 1.5 generation Asian Indians out of their total population, a little over 10%, it is important to note how new this group is (qualitatively documented in the historical literature). Almost all the U.S. born Asian Indians are probably 1st generation, rather than later generations for whom the immigrant experience is more distant. So, I find it surprising (and personally positive) that Asian Indians are demographically integrating with the general American population so quickly. The contrasts and comparisons with older and more generationally heterogeneous Asian American communities such as the Chinese or Japanese is surprising. For example, over 3/4 of Japanese Americans are U.S. born or 1.5 generation, with many in the 2nd, 3rd and 4th generations after the first native-born cohort, and their intermarriage rate with whites is 20.3% and 42.3% for men and women respectively . This indicates a fair amount of demographic integration, but the first Asian Indian generations are in the same statistical ball-park as Japanese who have been resident in the United States for 100 years!
Update below: control-f "Updated point"!
Update II: addendum below
What could account for this? First, I would like to offer a dissent from the position that the data on Asian Indians is illustrative of any general trend. Last I talked to him about this topic, Vinod pointed out that the data was from the 2000 Census, and assuming that the mean age of marriage of young Asian Indians of this age cohort is somewhere in the mid-20s to 30s, these are the children of the "first wave" immigrants of the 1960s and 1970s. The "first wave" was top-heavy with medical doctors and those with advanced degrees in the sciences. They arrived at a time when Asian Indians were a neglible demographic presence, and no large communities of South Asians existed in the United States (excluding the peculiar quasi-Sikhs of the Central Valley who generally assimilated to their mother's Mexican culture). Demographically isolated, and not able to communicate with the homeland through cheap calling cards, flights and information technology, they had no choice but to integrate with their surroundings.
The waves of immigration of Asian Indians that came in the 1980s and 1990s were more working class, and they were able to settle in commmunities that offered an Asian Indian milieu, often in and around the greater New York City area. Unlike the "first wave," they did not have to integrate beyond learning enough English to get by if they so chose. Their children likely did not show up in the 2000 Census statistics, as they wouldn't be old enough. I know little about this generation, but I can say from personal experience, that my younger siblings, who are in their early teens, are in some salient ways, more South Asian in their identity than my brother or I, who grew up amongst Irish and Italian American kids in upstate New York or in Mormon eastern Imbler. Because, on average, their parents have less education than the "first wave," it seems plausible that a larger portion of the children of the "second" wave will not pursue higher education, and so immerse themselves in an environment where they are pulled away from a South Asian identity (unless they go to study engineering at Stanford!). The possible lower earning power and educational attainment of the children of the "second wave" will make them less attractive as partners for mainstream native-born Americans. And of course, there will be the statistically reality that there are likely to be more South Asian partners on the market than there were for the children of the late 60s to early 80s .
But, let's ignore the very real possibility that this enormous spike in intermarriage in one generation is a fluke. What could account for it? Here are a few possible factors:
There are of course other, non-political reasons for the emergence of South Asian identity. Personal ease and comfort, "being among your own," is a reason given by some. Today, all South Asians, no matter their accent or cadence, their educational qualifications or income, tend to be touched by the aura of exoticism when dealing with non-South Asians. Some South Asians believe a common desi identity and community serves as a refuge from the mild alienation of white American society. This sort of perspective is contingent on one's personality. I have never had these issues because I have always stood out in whatever context I have situated myself in, non-brown or brown. From a selfish perspective, all someone like me would gain from the emergence of a desi identity is extra baggage on top of the exoticism that already exists. I am highly alienated from my natal religion, have little racial feeling, and tend to empathize more with those who share my intellectual mind-set than an affinal cultural or genetic lineage (the cultural affinity is only apparent based on my physical appearence, I find much more of value in Polybius than Kautilya, more wisdom in Confucius than the Buddha. As for the genetic element, the high degree of variance in phenotype among South Asians undermines this to some extent). Also, integrated over generations, the creation of a desi identity will likely retard the diminishment of the aura of exoticism that many South Asian youth wish to flee from. Creating a subcultures seals one off from the negatives of the surrounding culture, but diminishes the exchange of ideas and blood that brings the two groups together, so I appeal to my fellow South Asian youth to think of their mongrel grand-children when they feel a bit out of place. Finally, one thing that is certain, the lack of intermarriage between South Asians and other Asian American groups shows to me that as the years pass by, South Asians will probably withdraw from the umbrella of Asian American interest groups. The "Asian American" group is a fiction, the real clusters of East, Southeast and Southeast Asians stitched together by a political elite that is self-interested in attempting to maximize their numbers.
Addendum: According to this report, 13% of couples with a South Asian in it are "mixed" in Canada. This is higher than the total for the United States (that is, all generations & immigration cohorts lumped together). As far as the UK goes, this claims that "inter-racial relationships were flourishing with a fifth of Asian men and 10% of Asian women opting for a white partner" (source study, circa 1997). Asian in this context is usually South Asian.
 I use Japanese Americans because I suspect that this group is less prone to having the male-female imbalance of intermarriage be exaggerated by "war brides," though this surely is a factor as the United States did occupy Japan after World War II.
 Manish seemed to find the high intermarriage rates implausible. I pointed out this might be a function of his residence in a large urban area with a critical mass of South Asians, where there are many options as far as partners goes. In may rural areas, one is often the only brown face for miles (I speak from experience), and celibacy does not appeal to many. So you could have a tendency for most of the majority of urban South Asian youth to marry within their own ethnic group, while over 95% of the minority who live in small towns might marry non-South Asians.
Slouching toward mediocrity, yes, heading off the precipice, not yet....
Ed Rubenstein has a piece over at VDARE titled Bad News About Those South Asian Model Immigrants. There is plenty of bad news to report, or, more frankly, less good news. In the early 1980s most of the South Asians who were working class my family was aware of were illegals, or the odd poor relations of a professional (in other words, they were rare). Now, we live in a nation where convenience stores, taxi cabs and motels are as much the haunting grounds of brown folk as the halls of academe or hospitals. Things could be worse (at least they work), but the important thing to note is that the American immigration system has shifted a stream of highly educated professionals into a river of mediocrity in one generation!  From a selfish perspective, all South Asians who live in the United States have a stake in reorienting the immigration system toward more selectivity from an individual (as opposed to familial) vantage point, because the convenience store clerk rivals the medical professional in the minds of many Americans as the stereotypical brown person . One can easily imagine the consequences of this trend on the sexual or professional plane for those who do not strike a high enough individual profile, and get tagged with rational assessments based on group identity.
That being said, I have to express some reservations toward Ed Rubenstein's piece. He notes:
When were the Hmong among the South Asians that are profiled in laudatory tones in major glossies??? The educated American usually makes obvious typological distinctions between East Asians, Southeast Asians and South Asians . The Hmong came as refugees, so they don't even fit the pattern that Rubenstein points to when he characterizes South Asians, that they came as professionals in the 1960s and 1970s, with family reunification kicking in later. Look at the table that Rubenstein provides, and the "South Asian" ethnicities are pretty obvious (the ones Rubenstein must have been imagining when he speaks of professional first waves in the 1960s and 1970s), Indians, Bangladeshis, Pakistanis and Sri Lankans. When I calculated the poverty rate for these four groups, I got 10.6% (still 2% above native born whites, so Rubenstein could have played up that angle!) . I'm sure VDARE readers are smart enough to focus on the long term trend, less individual capital influx per person, rather than the reality that the present isn't quite that bad. No need to behave as if the numbers are more obscure than they are.
 Anecdotally, I know many children of motel owners and convenience store clerks who are in graduate or professional school, or in the private sector after gaining their college degree. I am not convinced that the descendents of the poor relations are destined to become members of the underclass. Nevertheless, if a lineage has individual capital, it should show up at some point down the line, and would be rewarded by a meritocratic system of immigration.
 I was asked by a Safeway clerk about how to pronounce an Indian name that she saw often. She wrote down "Nguyen." But again, I assume the target audience of VDARE is not Safeway checkout clerks.
 Interestingly the Japanese immigrant group has very high poverty rates (17%). This is probably due to the destitution of aged Issei, as most Japanese Americans are native born, so "immigrants" would skew to the post-retirement cohort. The general senior citizen poverty rate is about 10%.
June 22, 2004
The next War?
I've been following closely Venezualan politics for sometime now (the fact that they are the largest producer of oil in the western hemisphere taken over by a pro-Castro madman [redundant] has alway concerned me) so this article from Wapo really disturbs me. Quote from article;
" The Democratic Charter authorizes the OAS [Organization of American States] to respond actively to threats to democracy in the region, ranging from coup d'états to government policies that undermine the democratic process, and it identifies judicial independence as an essential component of a democratic system."
The "threat" to democracy is of course Chavez "loading the bench" of the Supreme court (from 20 justices to 32) and the ability of his coalition to nullify the appointment of sitting judges. Effectively turning the Venezualan judiciary into a complete joke.
will- The neocons see "respond actively" as military action
won't- Election 3 months following Venezuelan recall
I would favor any strong action being used by the Bush admin short of invasion that would oust Chavez (and the more paranoid left-wingnuts will say that Bush has already tried a Coup in 2002) since, in the short and long term, Chavez is bad for both his country and for the hemisphere as a whole. Maybe we could revive gunboat diplomacy?
Sexual selection & The Mating Mind
I'm reading Geoffrey Miller's The Mating Mind right now (see David B's review, only 1/4 of the way through, I echo most of his objections already). Human females, unlike most mammals, have to engage in display because if the importance of long term pair-bonding, making males "choosy" (follow the last link).
June 21, 2004
They say there are now more Mormons than Presbyterians in the United States. Well, on a recent trip to the east coast, I was talking to a friend who just got a position at University of Utah, and I realized talking to him he didn't know much about the religion. Going to a high school that was ~50% Mormon, I know a bit about their ways, below are a few "fun facts" for readers to chew on.
1) Mormons don't believe in the Trinity. God, Jesus and the Holy Ghost are distinct agents.
2) The Latter Day Saints Church (the main Mormon group) accepts the existence of a Heavenly Mother, the wife of God.
3) Mormons are not monotheists, they are henotheistic, in that they worship one god (God the Father), but accept the reality of other deities. In addition to the Heavenly Mother, Jesus and the Holy Ghost, Mormons usually also believe that other planets have their own gods.
4) Because, Mormons believe that god was a man, as were the gods of other planets.
5) Some righteous Mormons will also become gods.
6) Mormons do not believe in hell, rather, righteous gentiles go to a lower level of heaven. Even evil gentiles go to an after-life, which some Mormons believe is superior to this life. Only apostate Mormons go to something called the "Outer Darkness."
7) Mormonism began in the context of Joseph Smith's affiliation with the Universalist religion (now part of Unitarian-Universalism). This explains the lack of heaven, and also, posthumous baptism (everyone has a chance at heaven).
8) Mormons reject earthly polygamy, but if a man is "sealed" to a woman, she is to be his wife in the after-life. If he divorces, she still remains his wife, and if he remarries, and is "sealed" again, the second woman will be added to the tally of wives in heaven.
9) Mormons believe some Native Americans are descended from Jews. I haven't seen mtDNA or NRY studies that indicate a Jewish lineage, but the believers believe.
10) They wear sacred underwear.
11) Their rituals have a lot of freemason practices because Smith was associated with the masons.
12) They believe that Jesus and Satan are brothers.
13) The star Kolob is the closest to where God lives. God is a physical being, he does not sit on a "topless throne."
14) Yes, the Mormons used to think that black Africans were unfit for the priesthood until 1978.
15) Mormonism is pretty up-to-date, for 1830! The problem with creating a religion in the light of history is that you can see how man-made these sort of belief systems are, and how influenced they are by their social context. After all, if Mormonism was a religion founded in 1970, their segregationist racialism and bizarre ideas about New World history would not have been part of the package. Rather, they would have incorporated the World-As-We-Know-It in 1970.
16) Their church is rich. One of the richest entities in the United States.
"Proof" of history
A few months ago, I read The Barbarian Conversion, which detailed the transition of post & extra-Roman peoples from paganism to Christianity. One chapter, "Rival Monotheisms," dealt with the challenge posed by both Islam and Judaism. The author makes the case that conversion to Judaism from Christianity was a common event during the early medieval period (ergo, the later institutionalization of anti-semitism), in large part because of the familial similarity between the two faiths.
The above book was sent to the printers late in 1999, and 6 months later, a paper was published that suggested that the male lineages of European Jews were predominantly non-European in origin (an admixture rate on the order <0.5%.per generation). The point of course is that history is supposed to be a description of the past, and to a lesser extent, a theoretical model explaining how and why the past came about as it did (one can assert I have this ass-backwards, which is fine, go read your Spengler and Toynbee and leave me alone). In reality, historians seem so narrow in their focus, and so dependent on their traditional methodology (in particular, a small number of literary sources), that most (there are exceptions) seem ignorant of the avalanche of data coming out of genetics. The rise of a Post-Modernism in departments of history is especially shocking in light of the fact that more tools are now available for a scholar to form a multi-dimensional model of the past (eg; The Human Web)-there is frankly far less excuse to write an invented narrative than ever, though perhaps more inclination .
June 20, 2004
Shy blue eyed boys
His theory is speculative, suggesting that when people migrated to northern Europe they were faced with the problem of keeping up a body temperature that was used to a warmer climate. A mutation that increased the efficiency of the sympathetic nervous system and upped the level of norepinephrine...would have also raised the body temperature and offered a survival advantage. Unfortunately, it would have left them with a more reactive nervous system and a more timorous temperament. Where does the pigment come in? High levels of norepinephrine can inhibit the production of melanin in the iris and can increase the level of circulating glucosteroids that can inhibit melanin production as well. So blond hair and blue eyes and shyness may be a common biological package....
This seems an example of correlated response, the fitness cost of being extremely introverted in the northern European context is balanced in this case by other considerations (whether it be direct adaptation to the environment or sexual advantages). I would also not be surprised if in the EEA, where bands would be very large at 100 individuals (perhaps much smaller in Ice Age Europe) and inter-tribal interactions might have been rare, the relative fitness cost of being shy around "strangers" would have been much smaller, since there was little possibility of building large social networks which one could use to enhance social status, ergo, reproductive success. Contrast this with the "modern" context, attested to in books like The Tipping Point, where "connectors" can serve as nodes for social networks on the order of thousands of individuals, and parlay their gregariousness into careers in sales or leadership positions in business or government. I will make a tentative prediction that populations with a longer history of dense living & complex social structures [agriculture, urbanism] will have a smaller proportion of "shy" individuals.
In any case, the book above was published in 2000, so the author did not write with knowledge of the recent work that suggests northern peoples have a cold adapted metabolism. For those curious, here is Kagan's original article (he seems not to have fleshed out his theory much at this point), and a follow-up by another researcher that suggests that only blue-eyed males are particularly shy (blue-eyed females showing no difference). The above studies seem to have had samples composed of peoples of European ancestry, so one need not presume that brown-eyed Japanese are on average more outgoing than blue-eyed Swedes.