Stanislav Petrov and our common humanity


The first time I watched Gorky Park in the 1980s I remember how strange it was to see citizens of the Soviet Union, or as we called them all then irrespective of ethnicity, “Russians,” with normal human motivations and concerns. In other words, depicted in the fullness of their humanity.

As a child in Reagan’s America what we knew about Russians was that they were citizens of the Soviet Union, and what we knew about the Soviet Union were military parades and the dour mien of their leaders. When Mikhail Gorbachev emerged on the scene it didn’t really humanize the citizens of the Soviet Union. Rather, he was a totem or exemplar of a new spirit in the world, and that perhaps we weren’t all doomed to nuclear annihilation.

As for Russians. Who were they? In the 1990s they were our allies somehow, at least on paper. I think the truth of the matter is that we did take advantage of them as a nation and a people who were experiencing difficulties, insofar as America maneuvered itself into even more advantageous positions while they were down on their luck. Eventually, the images of godless Communists faded in the 1990s…to be replaced by kleptocrats and Russian mafia.

This is not to say I do not believe Communism was evil. I do believe it was evil. But, normal human beings with the same concerns and aspirations as those in the West were part of a system, which on occasion made them the tools of evil in this world. For that, perhaps they must be judged. Some say the same of American citizens. I may disagree in the particulars…but the principle is the same.

I bring this up because recently we found out that Stanislav Petrov died last spring. His story is well known at this point; he made a judgment call and ignored a false alarm that five American ICBMs were headed toward the Soviet Union. He acted humanely in a moment of high drama. As an American we are so often drilled into repeating the mantra we are the “good guys.” Petrov shows us that decency persisted even in the “evil empire.”

Amazon pepper sauce

Something different today when it comes to the condiment of choice. So I’m privileged to work at a company where the boss adds different hot sauces to our Instacart orders for the office. So we get to sample the good with the bad (usually not bad, just not exceptional).

You stumble upon some real gems in that way. The Green Amazon pepper sauce isn’t the hottest that’s graced my palette by a long-shot, though it packs more of a punch than tabasco. But its tart pungency gives you a huge wallop. Think the pepperoncinis you used to get with pizza or in antipasto. But livelier and spicier.

Overall a definite keeper, Green Amazon is literally flavorful, with tang and spiciness, and a bit of savor as well.

Population structure in Neanderthals leads to genetic homogeneity


The above tweet is in response to a article which reports on the finding past month in PNAS, Early history of Neanderthals and Denisovans. It’s open access, you should read it. I don’t think I’ve reviewed it because I haven’t dug through the supplements. To be frank this is a paper where you pretty much have to read the supplements because they’re introducing a somewhat different model here than is the norm.

I talked to Alan Rogers at SMBE about this paper. Broadly, I think there might be something to it, and it’s because of what David says above. It is simply hard to imagine that Neanderthals could be extremely successful with such low genetic diversity as we see, and spread so thin. Now, the Quanta Magazine tries to emphasize that the effective population is not the true census population, but I wish it would have explained it more clearly. Basically, the size that is relevant for breeding is obviously not going to the same as a head count. And, because effective populations are highly sensitive to bottlenecks you can get really small numbers even when the extant population at any given time may be large.

The PNAS paper makes some novel inferences, and I’ll set that to the side until I read the supplements. But I don’t think it’s crazy that population structure within Neanderthals could be leading to lower total genetic diversity.

Release the UK Biobank! (the prediction of height edition)


There’s so much science coming out of the UK Biobank it’s not even funny. It’s like getting the palantír or something.

Anyway, a preprint, submitted for your approval. A vision of things to come? Accurate Genomic Prediction Of Human Height:

We construct genomic predictors for heritable and extremely complex human quantitative traits (height, heel bone density, and educational attainment) using modern methods in high dimensional statistics (i.e., machine learning). Replication tests show that these predictors capture, respectively, ~40, 20, and 9 percent of total variance for the three traits. For example, predicted heights correlate ~0.65 with actual height; actual heights of most individuals in validation samples are within a few cm of the prediction. The variance captured for height is comparable to the estimated SNP heritability from GCTA (GREML) analysis, and seems to be close to its asymptotic value (i.e., as sample size goes to infinity), suggesting that we have captured most of the heritability for the SNPs used. Thus, our results resolve the common SNP portion of the “missing heritability” problem – i.e., the gap between prediction R-squared and SNP heritability. The ~20k activated SNPs in our height predictor reveal the genetic architecture of human height, at least for common SNPs. Our primary dataset is the UK Biobank cohort, comprised of almost 500k individual genotypes with multiple phenotypes. We also use other datasets and SNPs found in earlier GWAS for out-of-sample validation of our results.

A scatter-plot is worth a thousand derivations.

You know what better than 500,000 samples? One billion samples! A nerd can dream….

Black ancestry in white Americans of colonial background

I stumbled upon striking photographs of “white slaves” while reading The United States of the United Races: A Utopian History of Racial Mixing. The backstory here is that in the 19th century abolitionists realized that Northerners might be more horrified as to the nature of slavery if they could find children of mostly white ancestry, who nevertheless were born to slave mothers (and therefore were slaves themselves). So they found some children who had either been freed, or been emancipated, and dressed them up in more formal attire (a few more visibly black children were presented for contrast).

This illustrates that the media and elites have been using this ploy for a long time. I am talking about the Afghan girl photograph, or the foregrounding of blonde and blue-eyed Yezidi children. Recently I expressed some irritation on Twitter when there was a prominent photograph of a hazel-eyed Rohingya child refugee being passed around. Something like 1 in 500 people in that region of the world has hazel eyes! That couldn’t be a coincidence. Race matters when it comes to compassion.

But this post isn’t about that particular issue…rather, the images of enslaved white children brought me back to a tendency I’ve seen and wondered about: the old stock white Americans whose DNA results suggest ~1% or less Sub-Saharan ancestry. These are not uncommon, and I’ve looked at several of them (raw data). I’m pretty sure the vast majority at the 0.5% or more threshold are true positives, and probably many a bit below this (to my experience people from England and Ireland don’t get 0.3% African “noise” estimates with the modern high-density marker sets).

According to 23andMe’s database about 1 out of 10 white Southerners has African ancestry at the 1% threshold. It would be even more if you dropped to closer to 0.5%. And the DNA ancestry here understates the extent of what was going on: at about 10 generations back you are about 50% likely to inherit zero blocks of genomic ancestry from a given ancestor (assuming no inbreeding in the pedigree obviously). And this is exactly when a lot of the ancestry that is being detected seems to have “entered” the white population. In other words, for every person who is 1% African and 99% white American, they have a sibling who is 0% African and 100% white American, even though genealogically they share the same ancestors. Dropping the threshold to closer to 0.3%, and considering that even in the South there was migration from the North, and to a lesser extent Europe, after the Civil War, I wouldn’t be surprised if models of admixture inferred from the distributions we see indicate that over half the lowland Southern white population likely had genealogical descent from a black slave.

This all comes to mind because there aren’t too many records of people “passing” during this period. Those who deal in genealogy and encounter these cases of low fractions, which are nevertheless likely not false positives, almost never find a “paper trail” when they go look. And they look really hard.

The reason is obvious in the context of American history. Thomas Jefferson’s slave Sally Hemings had three white grandparents and one African slave grandparent. Several of her children are recorded to have been totally European in an appearance, and all except one passed into the white population (the two eldest married well into affluent white families in Washington D.C.). Passing as white was a way to escape the debilities of black status in the United States.

That being said, I think our Whig conception of the progressive nature of history sometimes misleads us in forgetting that the dynamics of race relations has had its ups and downs several times in the last few centuries in North America. If you read Daniel Walker Howe’s excellent What Hath God Wrought you observe that racial beliefs about the necessity and institutionalization of white supremacy in the early American republic evolved over time. Though the early republic would never be judged racially enlightened by modern lights, it was certainly far less explicitly racially conscious than what was the norm in the decades before the Civil War.

In particular, the rise of democratic populism during the tenure of Andrew Jackson was connected with much more muscular racial nationalism. To utilize a framework emphasized by David Cannadine in Ornamentalism, colonialism and Western civilization during the 19th and early 20th centuries can be viewed through the lens of race and class. Though the economic inequalities of American society persisted through the 19th century, men such as Andrew Jackson affected a more populist and rough-hewn persona than the aristocratic presidents of the early 19th century.* The white man’s republic had a leveling effect on the nature of elite culture.

But the attitudes toward racial segregation and mixing took decades to harden. Martin van Buren’s vice president, Richard Mentor Johnson, was well known to have had a common-law wife, Julia Chinn, who was a slave. He recognized his two daughters by her. He was vice president from 1837-1841 in the more racist of the two American political parties of the time. It is hard to imagine this being a viable “lifestyle” choice for someone of this prominence in later decades (after Julia Chinn’s death Johnson continued to enter into relationships with slaves).

Walter F. White, a black leader of the NAACP

Which brings us back to what was happening in the decades around 1800. Racism was a fact of life, necessitating the need for passing. But, beliefs about racial purity and the one drop rule had not hardened, so it would not be surprising to me that it was much easier for slaves or ex-slaves with mostly European ancestry to change their identity. Perhaps white Americans of that period were simply less vigilant about someone’s background because they were genuinely less concerned about the possibility that their partner may have had some black ancestry, so long as they looked white.

As the databases grow larger we’ll get a better sense of the demographic and genealogical dynamics. My suspicion is that we’ll see that there wasn’t much diminishment of gene flow into the black-identified community over the past 200 years, as much as the fact that hypo-descent, the one-drop rule, became so powerful in the between 1850 and 1950 we can confirm that passing declined, before rising again in the 1960s as whites became less vigilant due to decreased racism.

* As a middle class New Englander John Adams obviously was no aristocrat, but he was no populist either.

Open Thread, 9/17/2017

Reading Vietnam: A New History. The author has an apologia/explanation for why he is focusing not just on European colonialism, but the history of what became Vietnam back to the first contacts with Han China (with some perfunctory archaeological passages). This is great in theory, but from what I have read so far we’re going to have a tryst with the French sooner than later. So I don’t think he really delivered here (though perhaps “normal” people want to read about evil European colonialism immediately?).

By coincidence, there is a Ken Burns documentary on the Vietnam War now. One of my friends from when I was a kid had (has) a dad who was a Vietnam vet. He’d have night terrors. Only now do I realize how recently in the past it was for him back in the 1980s.

I did enjoy The Best and the Brightest.

Sent out my second newsletter. Here’s a stat that I divulged: more than 50% of traffic to this site is directly due to Google+Twitter+Facebook. In 2011 it was 35%. Much of the difference is due to the decline in RSS feeds, and the rise of mobile.

Why is Twitter not what it was in the early 2010s? I think part of it is that there are too many people on Twitter, and the average user is less intelligent overall. Unlike Facebook on Twitter the “genius” is anyone can talk to you. This is a problem.

The grandmaster of Mormon dweeb fantasy (I say this affectionately) Brandon Sanderson is coming out with the third book in his projected ten book Stormlight Archive series.

I’m at peace with the likelihood that I won’t finish this series. Sanderson is a great world-builder, so I’m looking at these books more as fictional ethnographies. Just along for a short ride.

Finally in the homestretch of A New History of Western Philosophy. After the classical period I haven’t really enjoyed this book, it was a slog. I began to read it at the same time as I read Consciousness and the Brain, which I finished in a week. Two years on I’m finally finishing the other book I started then.

Finally, again I highly recommend The Fortunes of Africa. Great read. I do have to say that it was hard not to be particularly appalled by Arab slave traders. It’s not like the European trade isn’t appalling, but that’s widely known. In contrast the driving of black Africans across the Sahara is less in the Western consciousness.

Massive genomic sample sizes = detecting evolution in real time

The recent PLOS BIOLOGY paper, Identifying genetic variants that affect viability in large cohorts, seems to have triggered a feeding frenzy in the media. For example, Big Think has put up Researchers Find Evidence That Human Evolution Is Still Actively Happening.

I wasn’t paying close attention because of course human evolution is still happening actively. From a genetic perspective, evolution is just change in allele frequencies. Populations aren’t infinite, so even if there wasn’t any selection stochastic forces would shift allele frequencies. But of course selection is probably happening. For adaptation by natural selection to occur you need heritable variation on a trait where there are fitness differences as a function of variation within the population. It seems implausible that these conditions don’t still apply. There’s plenty of fitness variation in the population, and it’s unlikely to be random as a function of heritable variation.

But the devil is in the details. And last year Field et al. used the modern genomic tools available to detect selection occurring over the past 2,000 years. It is not credible that it would have magically stopped a few centuries ago.

So why is this new paper such a big deal? (note that it’s in PLOS BIOLOGY, not PLOS GENETICS) Because the method they use is ingenious and simple. Basically, they’re looking at changes in allele frequencies as a function of age in huge populations. It’s a little more complicated than that, they used a logistic regression to control for some of the other variables. But they found some biologically plausible hits with their data set of 50,000-150,000. And, they replicated their hits from a European sample to a non-European one.

This does bring me back to a discussion I observed a while back. An evolutionary geneticist who works with Drosophila mentioned offhand that in his field there really wasn’t that much of a need for more data. They could spend all their time to doing analysis. A prominent human geneticist whose work focused on biomedicine piped up that that wasn’t true at all for their field. There are some differences in the scientific questions, but there are also differences in terms of what you can do with humans as a model organism.

In the paper they look forward to the day of increasing sample sizes an order of magnitude beyond where it is now. At some point in the near future, large fractions of entire nations will be sequenced at medical grade level (30x coverage).

Anyway, you should read Identifying genetic variants that affect viability in large cohorts. It’s pretty straightforward.

George R. R. Martin’s typical fantasy trope

George R. R. Martin has done something new in fantasy. He has created a world in shades of gray. This is in contrast to the modern template of J. R. R. Tolkien’s The Lord of the Rings, where what is good and what is evil were as clear and distinct as black and white. In addition, A Song of Ice and Fire transcended fantasy’s traditional appeal to adolescent males. This latter tendency is pretty evident in Robert Jordan’s The Wheel of Time, which was simply not moving beyond its juvenile origins by book seven or eight, when I gave up (I was moving beyond my juvenile origins by that point). It isn’t as if the Jordan-style, geared toward adolescent male virgins, can’t be done well. I’d argue that Brandon Sanderson pulls this off very competently.

One of the aspects of A Song of Ice and Fire in the books is there isn’t a Dark Lord who is the literal personification of evil. No Sauron. Even the primary antagonists become less dark with deeper exploration, and their motivations are often complex, and comprehensible in their own way.

But there is a major exception to this: Ramsay Snow and House Bolton. The Boltons are the great rivals of the Starks in the North, and before they were vassals they were kings. And they are evil in a straightforward sense without nuance. One stupid “fan theory” (these are the television show watchers) even posited that Roose Bolton was an immortal vampire.

Though Martin is careful to suggest that people should not take the antiquity of the dynasties in A Song of Ice and Fire literally, it is clear that the Bolton’s are not parvenus. Their lineage is old, and it has persisted. And yet the Boltons which are highlighted are basically without any redeeming qualities over their history. Ramsay Snow is basically the protagonist of a snuff film come alive.

When it comes to mining history perhaps the best analog to the Boltons were the Assyrians. Like the Boltons they flayed their enemies alive. The Assyrians also famously were totally destroyed by their enemies because of the ill-will their cruelty in conquest generated. Martin is a student of history, and there is no way that a lineage of such unmitigated evil could persist down the centuries. The Boltons exist as witness to the long tradition of fantasy antagonists which readers love to hate.