Language vs. genes, similarities & differences

Genetic and Linguistic Coevolution in Northern Island Melanesia:

…Here, we use high-quality data and novel methods to test two models of genetic and linguistic coevolution in Northern Island Melanesia, a region known for its complex history and remarkable biological and linguistic diversity. The first model predicts that congruent genetic and linguistic trees formed following serial population splits and isolation that occurred early in the settlement history of the region. The second model emphasizes the role of post-settlement exchange among neighboring groups in determining genetic and linguistic affinities. We rejected both models for the larger region, but found strong evidence for the post-settlement exchange model in the rugged interior of its largest island, where people have maintained close ties to their ancestral lands. The exchange (particularly genetic exchange) has obscured but not completely erased signals of early migrations into Island Melanesia, and such exchange has probably obscured early prehistory within other regions. In contrast, local exchange is less likely to have obscured evidence of population history at larger geographic scales.

Anthropology.net has already surveyed the paper, so if you’re interested in this specific result just go there. Rather, I want highlight a general point: linguistic and genetic variation are correlated, but the large residual highlights differences between the two.

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Statistics and religious trends

I have a piece up for The Guardian’s new Comment is Free Belief site, The use and abuse of statistics – Prophecies of the extinction of religion, or its triumph, fall prey to the weaknesses of linear prediction. Implicit in my argument are these sorts of dynamics:

Bearman and Brückner have also identified a peculiar dilemma: in some schools, if too many teens pledge, the effort basically collapses. Pledgers apparently gather strength from the sense that they are an embattled minority; once their numbers exceed thirty per cent, and proclaimed chastity becomes the norm, that special identity is lost….

This is in regards to virginity, but the insight is generalizable. You don’t have to know anything about dynamics though, just read a cultural history of France since the Revolution and you’ll see what I mean.

The fact of the irrational voter

Gov-Palin-2006_Official.jpgThe Political Gender Gap: Gender Bias in Facial Inferences that Predict Voting Behavior:

Contrary to the notion that people use deliberate, rational strategies when deciding whom to vote for in major political elections, research indicates that people use shallow decision heuristics, such as impressions of competence solely from a candidate’s facial appearance, when deciding whom to vote for. Because gender has previously been shown to affect a number of inferences made from the face, here we investigated the hypothesis that gender of both voter and candidate affects the kinds of facial impressions that predict voting behavior.
… Results indicate that both gender of voter and candidate affect the kinds of facial impressions that predict voting behavior. All voters are likely to vote for candidates who appear more competent. However, male candidates that appear more approachable and female candidates who appear more attractive are more likely to win votes. In particular, men are more likely to vote for attractive female candidates whereas women are more likely to vote for approachable male candidates.

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Statistics and religious trends

I have a piece up for The Guardian’s new Comment is Free Belief site, The use and abuse of statistics – Prophecies of the extinction of religion, or its triumph, fall prey to the weaknesses of linear prediction. Implicit in my argument are these sorts of dynamics:

Bearman and Bruckner have also identified a peculiar dilemma: in some schools, if too many teens pledge, the effort basically collapses. Pledgers apparently gather strength from the sense that they are an embattled minority; once their numbers exceed thirty per cent, and proclaimed chastity becomes the norm, that special identity is lost….

This is in regards to virginity, but the insight is generalizable. You don’t have to know anything about dynamics though, just read a cultural history of France since the Revolution and you’ll see what I mean.

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“Phoenician” DNA….

Dienekes and Kambiz both hit a new paper which claims to find the Y chromosomal (direct male descent lines) signatures of the ancient Phoenician colonization of the Mediterranean. I tend to see a lot of merit in Dienekes’ criticisms, the net here is thrown so wide that it’s almost one of those models where it explains everything so that it explains nothing. Compare this to the recent work on the genetics of the Etruscans and modern populations of Tuscany, which strongly lend credence to ancient myths of their origin in Anatolia The historical data I’ve seen suggests that both the Phoenician and Greek colonial expansions were characterized by an enormous male skew; the Rape of the Sabine Women echoes incidents which are alluded to in founding myths of several prominent cities in Magna Graecia. So sniffing around the Y is the way to go even if J2 is a false lead. In Carthage he noble lineage of Hannibal’s family had attested female ancestors who were Sicilian Greek, which implies that the Barcids were an amalgam of Greek, autochthonous Sicils, Berber as well as the male descent line from the Phoenician settlers from Tyre. Finally, do note that the likelihood of “supermale” lineages such as that of Genghis Khan doesn’t make it implausible for me that a handful of elite males hooked into the cheap and efficient Mediterranean transport network could have leave a very strong genetic imprint for the future. The Phoenician expansion into North Africa, Spain an Sicily is probably most well analogized to the Spanish conquistadors who subjugated the New World in less than a century.

Portfolio rollback

Condé Nast Cuts Focus on 2 Magazines:

Through the first nine months of the year, ad pages in all United States magazines were down 9.5 percent from the same period in 2007. Most magazines produced by Condé Nast – including Vogue, GQ, Architectural Digest and Wired – have had much smaller declines, but they are also among the most expensive magazines to produce.

Portfolio, started last year amid much fanfare, is Condé Nast’s first business magazine and its most expensive new project in years. Executives said the company was willing to lose more than $100 million on it.

I immediately thought of this, Can Si Newhouse Keep Condé Nast’s Gloss Going?:

Some extravagances have been curtailed, but no one in the business disputes that Condé still spends far more money than its competitors. Magazine publishers and editors in chief haul in $400,000 to $2 million in salary and bonuses, current and former executives say, and many executives have clothing allowances in the high five figures.

Last July, Vanity Fair printed 20 different versions of its cover, a daisy chain of celebrity pairs shot over many months and on multiple continents by Ms. Leibovitz, a project that cost millions. It paid for itself, says the magazine’s editor, Mr. Carter, in increased newsstand sales and buzz.

Mr. Phillips, the investment banker, observed, “I would say if you look across their whole portfolio, Condé Nast does a better job of producing high-quality magazines than anybody else in the industry.” But, he adds, “you really could spend a lot less money on those magazines without affecting quality.”

I remember thinking at the time that when the bubble bursts they’ll regret not running a more efficient operation. To some extent it seems like Advance treats its glossies like performance art as opposed to a business operation. Of course, S. I. Newhouse is nearly a 10 billionaire so I guess he can afford to be less orthodox than the typical billion-pinching mogul. At least The Big Money isn’t going anywhere.

H/T Tyler.

Jim Manzi on epistasis

Jim Manzi has a long post up on epistasis, that is, gene-gene interactions:

We could call this process of competing algorithms struggling to find the best solution as fast as possible “meta-evolution”. That is, each potential search method must compete for survival. The fact that the algorithm that has won this (idealized) competition in the real world has the form of a GA seems to indicate that there is some structure to the relationship between gene vectors and physical outcomes, but that it is much more complex that simple linear combinations without interaction terms, otherwise nature never would have evolved the evolutionary algorithm with all of its computational overhead. If epistatic interactions were not central, meta-evoltuion should have killed off evolution as we know it a long, long time ago.

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Evolution and trustworthiness

Evolution of trust and trustworthiness: social awareness favours personality differences (Open Access):

Interest in the evolution and maintenance of personality is burgeoning. Individuals of diverse animal species differ in their aggressiveness, fearfulness, sociability and activity. Strong trade-offs, mutation-selection balance, spatio-temporal fluctuations in selection, frequency dependence and good-genes mate choice are invoked to explain heritable personality variation, yet for continuous behavioural traits, it remains unclear which selective force is likely to maintain distinct polymorphisms. Using a model of trust and cooperation, we show how allowing individuals to monitor each other’s cooperative tendencies, at a cost, can select for heritable polymorphisms in trustworthiness. This variation, in turn, favours costly ‘social awareness’ in some individuals. Feedback of this sort can explain the individual differences in trust and trustworthiness so often documented by economists in experimental public goods games across a range of cultures. Our work adds to growing evidence that evolutionary game theorists can no longer afford to ignore the importance of real world inter-individual variation in their models.

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