Update: Stephen Dubner emailed me, and pointed me to this much longer segment which has a lot of Bryan Caplan. So it seems like the omission that I perceived was more of an issue with the production and editing process and constraints of the Marketplace segment than anything else.

End Update

I play a lot of podcasts during the day as I go about my business on my iPod shuffle. One of them is Marketplace, which has a regular Freakonomics Radio segment, where Stephen Dubner “freaks” you out with incredible facts and analysis, often with a helping hand from Steven Levitt. With all due respect to Dubner and Levitt, this still has very pre-Lehman feel. Economics has “solved” the workings of the explicit market, so why not move on to other areas which are ripe for conquest by the “logic of life?”

In any case this week’s episode kind of ticked me off just a little. It started off with the observation that college educated women apparently put 22 hours weekly into childcare today, vs. 13 hours in the 1980s. I guess fewer latchkey kids and more “helicopter parents?” Dubner basically indicates that the reasoning behind this is many parents are in a “red queen” arms race to polish the c.v.’s of their children for selective universities. This makes qualitative sense, but can we explain an increase of 9 hours on average for the ~25% of women who are college educated on striving to make sure that their kids have Wesleyan as the safety school?

Let’s put our quantitative “thinking-caps” on “freakonomics” style. ~25% of adults have university degrees. ~80% of these have public university degrees, which are usually not too selective. Some of the ~20% are from not particularly elite religious colleges. So the subset of Americans who graduated from elite universities is actually not too large a number. You can include these as natural aspirants for the best spots for their children. And a proportion of the large remainder, I’d estimate ~90%, who didn’t go to a university which required a great deal of stress and c.v. polishing would certainly strive and hope for better for their kids. But can this explain a 9 hour average rise among tens of millions of women? Doesn’t seem to pass the smell test for me. I suspect there’s a more general norm of shifting toward “high investment parenting” among the college educated cohorts.

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As I’ve been harping on and on for the past few years that the patterns of contemporary genetic variation are probably only weakly tied to past patterns of genetic variation (though Henry Harpending warned me about this as far back as 2004). A major reason that scholars operated under this presupposition is the axiom that most of the variation we see around us crystallized during the Last Glacial Maximum (~20 thousand years before the present).

This may be true in some cases, but I doubt it is true in most cases. I was pointed to a classic case of this problem just today. A reader alerted me to a short paper from this spring which attempts to ascertain the point of origin of the dominant mtDNA haplogroup among the Onge tribe of the Andaman Islanders, M31a1. This is an interesting issue because some researchers proposed, plausibly in the past, that these indigenous people in the Andaman Islands represent the descendants of the first wave “Out of Africa,” who took the rapid “beachcomber” path. Understanding the key to their genetics may then unlock the key to the “Out of Africa” event. Or so we thought. It looks like the human evolutionary past was a lot more complicated than we’d presumed.

The paper is in the Journal of Genetics and Genomics. Mitochondrial DNA evidence supports northeast Indian origin of the aboriginal Andamanese in the Late Paleolithic:

In view of the geographically closest location to Andaman archipelago, Myanmar was suggested to be the origin place of aboriginal Andamanese. However, for lacking any genetic information from this region, which has prevented to resolve the dispute on whether the aboriginal Andamanese were originated from mainland India or Myanmar. To solve this question and better understand the origin of the aboriginal Andamanese, we screened for haplogroups M31 (from which Andaman-specific lineage M31a1 branched off) and M32 among 846 mitochondrial DNAs (mtDNAs) sampled across Myanmar. As a result, two Myanmar individuals belonging to haplogroup M31 were identified, and completely sequencing the entire mtDNA genomes of both samples testified that the two M31 individuals observed in Myanmar were probably attributed to the recent gene flow from northeast India populations. Since no root lineages of haplogroup M31 or M32 were observed in Myanmar, it is unlikely that Myanmar may serve as the source place of the aboriginal Andamanese. To get further insight into the origin of this unique population, the detailed phylogenetic and phylogeographic analyses were performed by including additional 7 new entire mtDNA genomes and 113 M31 mtDNAs pinpointed from South Asian populations, and the results suggested that Andaman-specific M31a1 could in fact trace its origin to northeast India. Time estimation results further indicated that the Andaman archipelago was likely settled by modern humans from northeast India via the land-bridge which connected the Andaman archipelago and Myanmar around the Last Glacial Maximum (LGM), a scenario in well agreement with the evidence from linguistic and palaeoclimate studies.

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A Cape Coloured family

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I’ve mentioned the Cape Coloureds of South Africa on this weblog before. Culturally they’re Afrikaans in language and Dutch Reformed in religion (the possibly related Cape Malay group is Muslim, though also Afrikaans speaking traditionally). But racially they’re a very diverse lot. In this way they can be analogized to black Americans, who are about ~75% West African and ~25% Northern European, with the variance in ancestral proportions being such that ~10% are ~50% or more European in ancestry. The Cape Coloureds though are much more complex. Some of their ancestry is almost certainly Bantu African. This element is related to the West African affinities of black Americans. And, they have a Northern European element, which likely came in via the Dutch, German, and Huguenot settlers (mostly males). But the Cape Coloureds also have other contributions to their genetic heritage. Firstly, they have Khoisan ancestry, whether from Bushmen or Khoi. This is well known in their oral memory. The the hinterlands of the Cape of Good Hope are beyond the ecological range of the Bantu agricultural toolkit, so the region was still dominated by the Khoisan when the Europeans arrived. But there are also other suggestions of ancestry from Asia. The existence of the Cape Malays, whose adherence to Islam derives from the Muslims slaves brought by the Dutch, hints at likely relationships to the populations of maritime Southeast Asia. Finally, there are the Indians. This element is not too well recalled in cultural memory. But the Dutch brought many slaves from India as well as Southeast Asia. The Dutch first governor of the Cape Colony had a maternal grandmother who was an Indian slave, by various accounts Goan or Bengali (the town of Stellensbosch is named for him). No doubt it was far more likely that the usual lot of the descendants of Indian slaves during the Dutch era would be to be absorbed into the melange of the Coloured population than assimilated into what later became the Afrikaners.

Why is this aspect of Cape Coloured ancestry forgotten? I think part of the reason is that there is a large South African Indian community present today, but that community post-dates the Dutch period, and arrived with the British. When South Africans think of Indians they think of these people. Interestingly when the new genetic studies confirming Indian ancestry came on the scene I was “corrected” several times by Indians themselves when reporting this part of the Coloured heritage. They were under the impression I must be mistaken, as no one was familiar with the Cape Coloureds having Indian ancestry. Unfortunately pointing to PCA and STRUCTURE plots did not clear up the confusion.

In any case, thanks to the African Ancestry Project I now have three unrelated Coloured samples (I have more, but they are related). Since AAP is Afrocentric I thought it would be appropriate to run the Coloured samples separate first. So that’s what I did.

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As I am currently reading Victor Lieberman’s magisterial Strange Parallels: Volume 2. So I was very interested in a new paper from BMC Genetics, Genetic structure of the Mon-Khmer speaking groups and their affinity to the neighbouring Tai populations in Northern Thailand, pointed to by Dienekes today. Here are the results and conclusions:

A large fraction of genetic variation is observed within populations (about 80% and 90 % for mtDNA and the Y-chromosome, respectively). The genetic divergence between populations is much higher in Mon-Khmer than in Tai speaking groups, especially at the paternally inherited markers. The two major linguistic groups are genetically distinct, but only for a marginal fraction (1 to 2 %) of the total genetic variation. Genetic distances between populations correlate with their linguistic differences, whereas the geographic distance does not explain the genetic divergence pattern.

…

The Mon-Khmer speaking populations in northern Thailand exhibited the genetic divergence among each other and also when compared to Tai speaking peoples. The different drift effects and the post-marital residence patterns between the two linguistic groups are the explanation for a small but significant fraction of the genetic variation pattern within and between them.

There are many occasions when it has taken a synthetic scholar to point out to me the overall structure of a constellation of facts which I was conscious of prior. So it is with Lieberman’s work. I had known that the eruption of the Thai peoples into Southeast Asia occurred with the last 1,000 years, before which the peninsula was divided between Tibeto-Burman populations to the west and Austro-Asiatic languages to the east (the latter divided between the Khmer and Vietnamese). Additionally, it is presumed that the Tibeto-Burman languages themselves displaced Austro-Asiatic in the western zone (as evident by the persistence of Mon in modern Burma). What was noted in volume 1 of Strange Parallels though is that the three geographical regions engaged with and assimilated the Thai invasions different. In the center the Thai succeeded in dominating the previous groups and imposing their identity upon the region. It is often asserted that modern Cambodia’s existence as an independent state is a function of the protection conferred upon it by the French from the expansive ambitions of the Empire of Siam. But in the east the Vietnamese state was barely impacted by the Thai folk wandering. As in China the Thai in Vietnam are marginalized “mountain tribes.” Finally, in the west, in the zone which became Burma, the Thai did not take over the cultural commanding heights. But neither were they absolutely marginalized as in the east. Rather, the Shan people became part of the of the Burmese landscape, integrated into the Theravada Buddhist culture, but also a significant secondary ethnos to the Burman majority (along with Karens, Mons, etc.).

What does this have to do with genetics? Possibly everything and nothing, and all answers in between.

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First, Sam Snyder. Here’s the link to the file in dropbox.

Second, Heather Frawley. I’ve uploaded her text file as well as pedigree format at RapidShare as a zip file. Click “Free Download” at the bottom right of the page. It’ll take about ~5 minutes to pull down the 10 MB file.

Remember, if you want to have your public genotype posting publicized or want me to upload and format it, email me at contactgnxp -at- gmail -dot- com.

Zack and Dr. Daniel MacArthur have already pointed to the Interpretome tool (Chrome and Firefox only!). As Daniel noted the PCA option will probably be the most fun for people. Just load your raw (unzipped) 23andMe data file, and project yourself onto different population sets. Since I know how to use EIGENSOFT this isn’t too revolutionary for me, but I’ve been putting off analyzing my chromosomes’ ancestry segment by segment. Luckily Interpretome has a much better experimental “ancestry painting” than 23andMe. Just make sure to use the HapMap3 setting to get the most juice.

I used 40 individuals to compute my results, and it took less than 10 minutes. The reference populations below are African Americans, Bantu in Kenya, Mexican Americans, Gujaratis, Tuscans, and Chinese.

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The fruits of human cooperation

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The Pith: Human societies can solve the free rider problem, and generate social structure and complexity at a higher level than that of the band. That implies that much of human prehistory may have been characterized by supra-brand structures.

Why cooperation? Why social complexity? Why the ‘problem’ of altruism? These are issues which bubble up at the intersection of ethology and evolution. They also preoccupy thinkers in the social sciences who address fundamental questions. There are perhaps two major dimensions of the parameter space which are useful to consider here: the nature of the relationship between the cooperators, and the scale of the cooperation. An inclusive fitness framework tracks the relation between altruism and genetic relatedness. Reciprocal altruism and tit-for-tat don’t necessarily focus on the genetic relationship between the agents who exchange in mutually beneficial actions. But, in classical models they do tend to focus on dyadic relationships at a small scale.* That is, they’re methodologically individualistic at heart. So all complexity can be reduced to lower orders of organization. In economics a rational choice model of behavior is individualistic, as are the critiques out of behavioral economics.

There are other models which break out of this individualistic box, insofar as they make analogies between organisms at the individual scale to social entities which are aggregations of individuals (e.g., a colony or ethnic group). The society as an organism has an old intellectual pedigree, and was elaborated in great detail by Émile Durkheim. More recently David Sloan Wilson has attempted to resurrect this framework in an explicitly evolutionary sense. Wilson has also been the most vocal proponent of multi-level selection, which posits that the unit of selection can be above the level of the gene or individual. For example, selection operating upon distinctive ‘demes.’ Roughly, a breeding social unit.

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Three weeks ago I observed that Google trend data indicated that Facebook had finally plateaued in its growth in the USA. Today a story on data from Inside Facebook:

Facebook just lost a few faces. Six million users in the U.S. ditched their Facebook accounts last month. And the number of people using the site during the month of May also fell in Canada, Russia and the U.K. That’s according to new data from a company called Inside Facebook.

According to their data June 1st 2010 to June 1st 2011 Facebook grew ~20% in the USA, vs ~50% worldwide. There’s lots of room for growth in the rest of the world, but it may be that like the internet overall Facebook has hit its saturation point in the developed English speaking world. And I’m pretty happy with that. I get a lot fewer requests for annoying apps like “Mafia Wars.” Now that the novelty has worn off people are using the “social graph” tools of Facebook as background utilities (and since I have a set of “Facebook friends” who use twitter, I suspect that that’s cannibalizing some of the stuff that would otherwise be posted to Facebook).

According to Your Genetic Genealogist, it is:

1000 African American
3500 Latino/Hispanic
5500 East Asian
3400 South Asian
4900 Southern European
6200 Ashkenazi Jewish
56,000 Northern European
1,000 First generation from two continents

I’m kind of surprised that there are so few African Americans, since the marginal return on ancestry matching technologies for the black American community is going to be higher than for other groups. If these numbers are true then I have on the order of ~10% of the 23andMe genotypes for black Americans in the African Ancestry Project. Zack Ajmal referring to the over 3,000 South Asians quips: “Now if 10-20% of them would participate in Harappa Ancestry Project!” My main concern is that if HAP gets more well known Zack will have hundreds of Tamil Brahmins sending him pretty much duplicate genotypes.

Review of “Braintrust. What Neuroscience Tells Us about Morality”, by Patricia S. Churchland

The question of “where morals come from” has exercised philosophers, theologians and many others for millennia. It has lately, like many other questions previously addressed only through armchair rumination, become addressable empirically, through the combined approaches of modern neuroscience, genetics, psychology, anthropology and many other disciplines. From these approaches a naturalistic framework is emerging to explain the biological origins of moral behaviour. From this perspective, morality is neither objective nor transcendent – it is the pragmatic and culture-dependent expression of a set of neural systems that have evolved to allow our navigation of complex human social systems.

 

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