Last spring two very thorough papers came out which surveyed the genetic landscape of the Jewish people (my posts, Genetics & the Jews it’s still complicated, Genetics & the Jews). The novelty of the results was due to the fact that the research groups actually looked across the very diverse populations of the Diaspora, from Morocco, Eastern Europe, Ethiopia, to Iran. They constructed a broader framework in which we can understand how these populations came to be, and how they relate to each other. Additionally, they allow us to have more perspective as to the generalizability of medical genetics findings in the area of “Jewish diseases,” which for various reasons usually are actually findings for Ashkenazi Jews (the overwhelming majority of Jews outside of Israel, but only about half of Israeli Jews).

Just as the two aforementioned papers were deep explorations of the genetic history of the Jewish people, and allowed for a systematic understanding of their current relationships, a new paper in PNAS takes a slightly different tack. First, it zooms in on Ashkenazi Jews. The Jews whose ancestors are from the broad swath of Central Europe, and later expanded into Poland-Lithuania and Russia. The descendants of Litvaks, Galicians, and the assimilated Jewish minorities such as the Germans Jews. Second, though constrained to a narrower population set, the researchers put more of an emphasis on the evolutionary parameter of natural selection. Like any population Jews have been impacted by drift, selection, migration (and its variant admixture), and mutation. Teasing apart these disparate parameters may aid in understanding the origin of Jewish diseases.

The paper is open access, so you don’t have to take my interpretation as the last word. Signatures of founder effects, admixture, and selection in the Ashkenazi Jewish population:

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The autosomal genome of Ötzi the Austrian “Iceman” is apparently in the pipeline (from what I can tell they’re doing the analysis right now). What can we learn from one sample? Ann Stone, who was a graduate student on the original team which recovered his body, says:

A specialist in anthropological genetics, Stone is excited by the recent news but also cautious. “It is a sample of one. For us to really say something about that period, you need a sample of 25 to 50 individuals,” she explained during an interview with Deutsche Welle, Germany’s international broadcaster.

This is fine as it goes. Worries about sample size are pretty generic and if the practicalities permitted who wouldn’t want a bigger N? But whether you should worry about sample size is partly conditional on how much the findings deviate from what you’d expect. Imagine for example that ~25% of Ötzi’s genome was of Neandertal origin. Obviously it would be great to have 25 to 50 representative individuals from this region to know whether Ötzi was atypical…but the very finding itself would be of such large effect that an N = 1 would tell us quite a bit. Similarly, one genome of a Sub-Saharan African would be very informative if you had several hundred non-African genomes as a point of comparison (because Sub-Saharan Africans have so much genetic variation which is outside of the distribution found among non-Africans).

Essential Science Fiction Movies. People always put Metropolis on the list, or bemoan the fact that they haven’t seen it. What do you think of it? I quite enjoyed, but much of the greatness of the film seems to be that it prefigured so much of what was to come.

The Real Estate Collapse. Jonah Lehrer suggests that the problem with prices not declining (or at least listed prices) has a lot to do with loss aversion/sunk cost fallacy. I agree. On the other hand, many Americans who are older bought into the idea that real estate was the “safe” place to put their savings, and now are looking at taking a big loss. If you have 15-30 good years left it might be really hard to simply “move on” when you don’t have the time left to rebuild equity.

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A reader asked about the bizarre story of Adolf Hitler having “non-Aryan” ancestry. Specifically, The Daily Mail title is: “DNA tests reveal ‘Hitler was descended from the Jews and Africans he hated.'” Since it’s a British newspaper I frankly wouldn’t put it past them to simply pass along a hoax…but I think if they were going to do that they would have said it was the Cohen Modal Haplotype. The article claims that Hitler’s Y lineage was haplogroup E1b1b (all biological descendants of the same common male ancestor through the direct patriline will carry this set of Y chromosomal markers). This is really vague, as the haplogroup has many subclades. Obviously if you pull the lens far back enough you’ll find a phylogeny where Hitler and Jews and/or Africans are within the same clade. Dienekes notes that this is not a rare haplogroup. It is correct that if one is an Ashkenazi Jew the odds of one carrying this haplogroup are much higher. But, it is not necessarily entailed from this that one is likely to be an Ashkenazi Jew if one carries this haplogroup (or is of Ashkenazi Jewish descent).

This is clear from the map of the distribution of E1b1b’s two major subclades:

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I don’t know about you, but I have a weird mental problem whereby my visual model of the past is strongly shaped by the constraints on the various representational modes which preserve images from a particular era. For example, the paintings of the 18th century shape how I imagine the 18th century, while the black and white photos of the early 20th century tend to drain color out of that period from my mind’s eye. So it’s always of interest to me when extremely old color photographs are discovered. A reminder to my subconscious that the past looked just like the present in many ways. But this set from The Boston Globe are so good that it’s mind blowing. All the images are from between 1909 and 1912, and within the boundaries of the Russian Empire.

Here’s a sample:

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On the heels of my post on cousin marriage, I thought readers might find this article on genetic screening in the United Arab Emirates of interest. One way to tackle the problem of genetic diseases which emerge out of consanguineous unions apparently isn’t to discourage the unions themselves, but dodge the outcomes. So pre-implantation screening of eggs as well as selective abortion of fetuses both seem to be options being evaluated. Aside from the costs, especially in the former case (though abortions are not without risk, and the initial stages of pregnancy are an investment of time as well), I still think there are long term problems with this. But first, Alan Bittles (who produced the map in the previous post) points to a major shortfall of a simple do-not-marry-cousins heuristic in this case:

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There is a new paper in Nature which is a full frontal attack on the utility of William D. Hamilton’s inclusive fitness framework in explaining eusociality. Martin A. Nowak, Corina E. Tarnita, & Edward O. Wilson are the authors. Wilson is famous in large part for his authorship of Sociobiology: The New Synthesis, and is arguably the doyen of American organismic biology. He is both an active scientist, and, a premier public intellectual. So with that in mind, I notice that Dienekes Pontikos alludes to “E.O. Wilson’s change of mind about group selection.” This is conventional wisdom, but it is I think wrong (though from what I can tell Wilson has not done much to disabuse the press of the notion). In Defenders of the Truth Ullica Segerstrale notes that Wilson did not expunge group selection thinking even in Sociobiology. In Evolution for Everyone David Sloan Wilson recounts that it was in fact E. O. Wilson who pointed out a group selective interpretation of data he was presenting at a conference, helping to push him early on in a rather unfashionable direction. From what I have heard Wilson always believed that the empirical data was not adequately explained by a pure inclusive fitness model, and simply waited until things shook out before pushing back with more theoretically trained colleagues who had the same skepticism.

From page 30 of Sociobiology:

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Welcome (and Welcome Back) to FiveThirtyEight. Nate Silver moves to The New York Times. Now if only we could get rid of those stupid made up “trend stories.”

Image of inflation adjusted home prices 1890-2006. Crazy! Classic case of a bubble, but it really hasn’t popped. And the government will try and make sure it doesn’t.

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There is a border across which fertility drops by a factor of two in North America (defined as from Canada to Panama). Specifically, one nation has a TFR of ~4, and the other ~2. Can you guess the two nations? You can find the answer in the charts below.

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The map above shows the distribution of consanguineous marriages. As you can see there’s a fair amount of cross-cultural variation. In the United States there’s a stereotype of cousin marriage being the practice of backward hillbillies or royalty. For typical middle class folk it’s relatively taboo, with different legal regimes by state. The history of cousin marriage in the West has been one of ups & downs. Marriage between close relatives was not unknown in antiquity. The pagan emperor Claudius married his niece Agrippina the Younger, while the Christian emperor Heraclius married his niece Martina. Marriage between cousins were presumably more common. With the rise in the West of the Roman Catholic Church marriages between cousins were officially more constrained. Adam Bellow argues in In Praise of Nepotism: A Natural History that there’s a material explanation for this: the Roman church used its power over the sacrament of marriage to control the aristocracy. Though the church required dispensations for marriages between cousins of even distant degrees of separation, they were routinely given, as was obviously the case among Roman Catholic royal families like the Hapsburgs. But once given the dispensation could be revoked, rendering the marriage null and void. A highly convenient power politically.

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