Month: April 2018

European hunter-gatherers were mostly replaced, but not totally. And they were neither black nor white

Posted on by Razib Khan

Peter Frost over at his blog has a long post on the transition to agriculture and pastoralism in Northern Europe.

He tagged me on Twitter, so presumably, he’s soliciting my opinion/response.

The post starts off with a quick reference to the attempt to leverage massive replacement in Northern Europe eight to four thousand years ago in the interests of contemporary politics. I’m not going to address that because I’m not very interested in how these topics relate, and I won’t post comments (or will delete) that engage with that. I will focus on the science.

First, I tried to leave a comment on his weblog and blogger ate it. So I’m just going to put a post here in the interests of open exchange. I also think many readers here have some of the same opinions as Peter, or suspicions, so it might be best to clear things up.

I don’t think his Peter’s argument can really be understood without reading his 2006 paper, European hair and eye color: A case of frequency-dependent sexual selection? My opinion in regards to this hypothesis is that I think it’s probably wrong and I’m skeptical. More skeptical than I was when I first read the paper because we have more understanding of the process of the settlement of Europe during the late Pleistocene and early Holocene. But, there is still a small window for it to be correct, as one can see in Peter’s post.

The argument hinges a lot on the pigmentation profiles of proto-European groups based on predictions from algorithms which use modern Europeans as a training set. These predictions are in the papers themselves, so Peter isn’t doing anything that the authors didn’t do. But, I have come to the conclusion that they’re probably not trustworthy. These ancient populations were very different from modern Europeans, and their genetic architecture for pigmentation may have been different (modern Europeans are a compound of several groups).

Though Mesolithic Western European hunter-gatherers were probably darker in complexion than modern Europeans, I believe it is likely that they were not nearly as dark as pigmentation prediction algorithms suggest. Second, it is true that alleles correlated with blonde hair in Europeans within the KITLG locus are found in Siberia nearly 20,000 years ago. But it is not true that “Ancient DNA from Afontova Gora has shown that people had blond hair in mid-Siberia as early as 18,000 years ago.”

What has been found is that Europeans who carry the derived variant at rs12821256 are more likely to have blonde hair. Those who are heterozygote are twice as likely, while homozygotes are four times as likely. At least against the population base rate. The frequency in Scandinavia of the derived variant is ~20%. Many blonde people don’t have the derived variant. And, not all people who have the derived variant have blonde hair.

Of my three children two are heterozygotes for the derived variant (they carry one copy). Probably not coincidently these two have lighter hair than the third. But neither are really blonde, though perhaps they are blond(ish) during certain times of the year. More accurately their hair is probably sandy brown. Why? I’m their father, and as a normally complected South Asia, I give them a host of alleles at other loci which make them different from the typical European genetic architecture of pigmentation.

As I said earlier Peter can’t really be blamed for making these inferences because they are in the scientific literature themselves. But just because they’re there doesn’t make them true (though I do think Peter should be careful about extrapolating from odds ratios against a particular base rate probability to some deterministic relationship).

A final issue is the idea that the alleles that define modern Northern European pigmentation were present in Scandinavian and Eastern European hunter-gatherers. This is correct. But again, modern prediction algorithms are trained groups with modern genetic backgrounds. In mixed populations, the largest effect QTLs explain only half the variance in pigmentation. The rest of it is accounted for by “genomic ancestry”, which basically means there are loci associated with ancestral groups that haven’t been discovered yet. But a second and more important issue is that the frequency of some the alleles in modern Northern European groups is different from what you find in the ancient ones. The ancestral variant on SLC24A5 is almost impossible to find in Northern Europe in indigenous people today (in Europeans the ancestral variant is most often found in Spain, due to admixture with Africa during the Moorish period). I don’t need to review the literature, but there is evidence for a fair amount of selection on these loci within the last 4,000 years. Even SHG and EHG still segregated ancestral variants at higher frequencies that modern Europeans.

The second major theme in the blog post has to do with hunter-gatherer ancestry. There’s a section on haplogroup U where Peter suggests that its disappearance is due to selection, not a replacement. U is associated with hunter-gatherer ancestry. This may be true, but mtDNA and Y need to be interpreted cautiously in any case (both R1b and R1a are far more common than one might predict from autosomal distributions of the ancestry of populations in which they were originally found).

Then there is the argument that bottlenecks/founder effects and natural selection might have skewed our estimates. I don’t really get the former argument at all:

Founder effects may be another causal factor. When bands of hunter-gatherers are given the opportunity to adopt farming, most of them turn up their noses and only a few will make the change. Because those few bands are not perfectly representative of the hunter-gatherer gene pool, and because their numbers may increase many times over (thanks to the increase in food supply) the resulting founder effects will be substantial.

These are verbal models, and unpersuasive to anyone who has looked at the data and generated results. Mesolithic hunter-gatherers were a genetically homogeneous lot to begin with. They didn’t have all this variance to sample from. There was later increase in hunter-gatherer ancestry into European farmers from demographic reservoirs, but the argument about founder effect doesn’t work because the two groups are so different that playing around with biasing the sample from which one mixes does not change the overall result. Replace hunter-gatherer and farmer with “Ashkenazi Jew” and “Chinese.” The latter two groups have some variance, but a bottleneck on one isn’t going to change one’s estimate of admixture in a daughter population.

The issue about selection suffers from the problem that the magnitude would have to be too large and extensive across the whole genome to reshape hunter-gatherers in this manner to be plausible. One might imagine a case where gene flow and selection on parts of the genome from the donor group inflates the donor group proportion…but I don’t think that’s Peter’s point? Theoretically, a model of admixture followed by sweeps around one population’s ancestry component is possible, but I don’t think we see evidence of that in the ancient DNA.

In any case, though the verbal argument seems reasonable on first blush, the models and dynamics don’t work out.

Peter ends:

Some of the confusion in this debate may arise from the assumption that “late hunter-gatherers” formed a single group in Europe. In fact, there were at least three such groups (WHGs, SHGs, EHGs), whose genetic profiles significantly differed from each other and whose fates were likewise different. WHGs were an evolutionary dead end. They were replaced. The same cannot be said for the hunter-fisher-gatherers of Scandinavia and the Baltic, who were able to achieve high population densities by exploiting marine resources (Price 1991). With them we see more genetic continuity than rupture, and it is possible that some genetic characteristics formerly ascribed solely to “Anatolian” farmers were in fact of SHG origin.

The people who are making the assertions that Peter is rebutting are not confused as to the nature of the populations which they named and which they modeled. Peter can download the data and replicate the analyses himself. WHG, SHG and EHG seem to exist on some sort of continuum, with post-“Villabruna cluster” ancestry at one end of the spectrum and post-Ancestral North Eurasian (ANE) ancestry at the other. WHG is mostly descended from ancestors of the Villabruna cluster, who share a common ancestry derived from late Pleistocene West Eurasians with Anatolian farmers (the latter of whom admixed with Basal Eurasians). EHG is a mix of the same Villabruna people (or at least their eastern fringe), but with a preponderance of ANE-like ancestry. SHG is between these two groups.

It also seems that European hunter-gatherers sometime in the late Pleistocene and or early Holocene recieved a small but detectable pulse of East Asian ancestry. Also, commonly shared haplotypes with West Asians on SLC24A5 (SHG and EHG) and EDAR with East Asians (SHG) indicates some gene flow with other places (though I believe SHG has no detectable East Asian ancestry).

Finally, there is much discussion of a late occupation of Northeast Europe by farmers. Since I predicted this 10 years ago I don’t have much objection to this section…except I don’t think that it supports his other points at all. That is, the persistence of hunter-gatherer populations around the Baltic does not mean that hunter-gatherers were more similar to farmers than we might think, nor does it reject the likelihood of total replacement in many areas of Europe to the south.

The overall conclusion here is two-fold:

  1. The assertions about pigmentation are not necessarily wrong, but they are far weaker based on the data that might be inferred from the post. Additionally, modern Europeans have lots of evidence of recent selection and allele frequency change at several of these loci.
  2. The assertions about very large misestimations of inferred mixing proportions are probably wrong.

Open Thread, 04/10/2018

Posted on by Razib Khan

About ~2/3 of the way through She Has Her Mother’s Laugh: The Powers, Perversions, and Potential of Heredity. It’s what you’d expect from a Carl Zimmer book, threading history with rock-solid attention to science. So far he’s actually been a really good, if popular, history of science. I say popular not pejoratively, but because the thematic and chronological structure isn’t academic, but hinges on more personal stories, whether it Carl’s own family, or people, famous and not so famous, with genetic issues that passed on down through the generations.

The book isn’t out yet, but you can pre-order of course. The current plan is to get Carl on The Insight (Stitcher, Google Play and web).

Speaking of which, it’s doing really well right now.

Because I’ve been pestering you, some of you have left nice feedback for us, which is pretty important over the long-term. I’ll probably keep on this until we reach 100 reviews on iTunes.

Last week’s episode on the topic Jewish genetics is the biggest one so far in terms of single-week downloads, and this week’s conversation with Stuart Ritchie should also pull in some interest. We talk a fair amount about Stuart’s book, Intelligence: All That Matters, and depressing topics such as the decline in fluid intelligence over a lifetime.

We’ll probably be revisiting intelligence and genetics with a future guest soon, but in the short-term we’ll pivot toward paleoanthropology since the AAPA is going on this week. I don’t know anything about bones so I’m going to mostly check out the pop-gen sessions, and then ask John Hawks for a core-dump at some point near the end of the week for the rest.

Because most people are ignorant heathens the “read the supplements” t-shirt did not sell well. But I got one for myself (we don’t comp ourselves, so I paid for it fair and square!).

Many rely on Twitter and Google Scholar, but I want to remind people of Pubchase and SciReader. They’re still useful to finding things right outside of your core zone of interest.

I mentioned the book The Invention of Humanity before. I was reading it before switching to Carl’s book (I want to prep for a podcast and I’m also going to give the book to someone else), and it’s OK, but it has the same problem as Inventing the Individual: intellectual history which engages in a sequence of inferences and asserts their validity by fiat without any argument.

There’s a lot to learn from books like this, but that mostly involves facts, rather than arguments (whose premises and method I generally find unpersuasive).

Randall Parker said he liked The Fate of Rome better than The Fall of Rome. On that recommendation, I got The Fate of Rome, as  The Fall of Rome is arguably my favorite history book of all time.

We’ll see.

Ezra Klein and Sam Harris had a podcast debate. I didn’t learn much new in this debate aside from how the two view each other (lots of commentary on the comments of the other).

But one thing I have to say is that Sam Harris’ contention that America’s racial caste system was not historically rooted in a biological conception of racial hierarchy is a point I agree with. By the late 19th and early 20th century, the public rhetoric was based on such an understanding, but that understanding developed organically over time with the emergence of taxonomy and then evolutionary biology in the 18th and 19th centuries.

Its origins are far more ancient, and arguably primal.

Though Daniel Walker Howe’s magisterial What Hath God Wrought is not about race fundamentally, it is a useful work to try and get a sense of how our modern conceptions of the white supremacist republic may mislead us in terms of how it was initially conceived (as on many things, white nationalists and people on the extreme cultural Left agree on many things about early America, where I think they are being anachronistic).

I think most readers now get a sense I am rather pessimistic about concepts such as public reason and getting the populace on board with ideas through persuasion. But, self-styled intellectual elites should still try to cultivate less stupidity and ignorance than is the case today. We’re led too often in the public arena by fools who can’t do their own data analysis, haven’t read the history books they were assigned in college, and whose goal is to seem smart enough to trick the masses than actually impress themselves with what they’ve achieved. Though I guess for most people impressing oneself is about the bank account.

The Rakhigarhi publication is supposed to be here within a month or so. But that’s what I was told a month or so ago. At this point I don’t expect to be surprised. We need to think about archaeology, linguistics, and mythology.

For your amusement:

Genetic influence on social outcomes during and after the Soviet era in Estonia. Heritability increases with meritocracy. That’s what you’d expect.

Slope or correlation, not variance explained, allow estimation of heritability.

Viktor Orban: Hungary PM re-elected for third term. 70% of the vote went to right-wing nationalist parties. Europe’s mainstream elite shouldn’t blame the people, they’re the ones who are promoting the worship of democracy as the only legitimate form of government. They need to blame themselves.

Comparison of phasing strategies for whole human genomes. Not a big surprise if you’ve tried this, but if you haven’t, a must read.

It looks like modal extra-pair paternity rates in human populations are in the range of 1-2%. Sorry aspiring cuckolds!

Arabia as Africa-across-the-sea

Posted on by Razib Khan

In antiquity ostriches and lions roamed the Syrian desert. The cheetah even still clings to a tenuous existence in the fastness of the central Iranian desert. The point being that the new finding of African modern human remains on the southeast fringe of Arabia ~85,000 years ago shouldn’t be too surprising. Old modern(ish) looking humans date to 73,000 years before the present in Southeast Asia. Modern-like ancestry can be found in eastern (Altai) Neanderthals dating to ~100,000 years ago. And the earliest humans may have arrived in Australia 65,000 years ago.

These dates are important because the genetic results indicate that much of the population divergence of modern Eurasian, Amerindian, and Oceanian peoples dates to the period between 50 to 60 thousand years ago. This was the classic epoch for the emergence of “behavioral modernity,” and the older models of “Out of Africa” which posited a rapid explosive demographic growth after a punctuated speciation even in East Africa ~60,000 years ago.

Today with remains such as Ust’-Ishim man, we can peg the admixture of Neanderthal into modern Eurasians 52,000 and 58,000 years ago. About the same period that the preponderance of the ancestry of modern Eurasians and peoples of Australia and the Americas expanded across the world, as noted above.

Most peoples in Western and Southern Eurasia also have substantial ancestry from another group which doesn’t seem to have much Neanderthal ancestry at all, the “Basal Eurasians” (BEu). This population obtained its name from the fact that it was hypothesized to have diverged from the common ancestors of northern Eurasians (the Pleistocene peoples of Europe and Siberia), eastern Eurasians, the ancestors of the Amerindians, and Oceanians, before these groups moved on and then separated (i.e., proto-Melanesians are closer to Pleistocene European hunter-gatherers than they are to BEu). These facts suggest proto-BEu was a distinct population >60,000 years ago.

The maximum range of Neanderthals

 

Because of the distribution of Neanderthal admixture across so many groups relatively evenly it probably came from a single major admixture event. Geography tells us that the most likely area of this admixture would be somewhere in the northern area of West Asia.

This implies that BEu was probably resident in the southern area of West Asia, and possibly into North Africa. We do not have any samples which are “pure BEu.” Ancient agriculturalist samples from the western Near East and the eastern Near East are high in BEu ~10,000+ years ago, but these populations are still substantially mixed with a population with affinities to Mesolithic Western European hunter-gatherers (WHG). Fu et al. 2016 use a Pleistocene transect to infer that this affinity between Near Easterners and Europeans dates to the period after ~15,000 years before the present. I presume that this late Pleistocene period was when BEu was admixed away as a pure population by an expanding hunter-gatherer culture with a nexus in Southeast Europe and into Anatolia and the trans-Caucasian region.

The recent Arabian find makes sense I think in the context of BEu and other such populations, which had diverged from the Africa metapopulation ~100,000 years ago, but had not pushed further north and east, and so mixed with Neanderthals.

But what about the older modern human remains which are showing up in eastern Eurasia? I think it is entirely likely that these populations left only a little bit of an imprint in modern groups. A paper from a few years back reported having detected such an admixture in Oceanians. The first ancient genome we have from eastern Eurasia >60,000 years ago that is from a modern human will probably yield much more satisfying results.

The big dynamic looming over the likely existence of anatomically modern human range on the edge of Africa in Arabia is that for several hundred thousand years modern humans existed within Africa as a metapopulation. The proto-Out-of-Africa population can only be understood as part of this broader metapopulation. ~100,000 years before the present humans, inclusive of Neanderthals, Denisovans, and modern humans, our species was probably defined by a set of distinct metapopulations. We know that there was gene flow between these metapopulations, but the strong evidence of purifying selection of Neanderthal and Denisovan ancestry in modern human genomes tells us that this gene flow was minimal enough that biological incompatibilities were beginning to build up and the groups were on their way to speciation as defined by the biological species concept.

There is no evidence of this between any modern populations, even the most diverged (e.g., the Khoisan, who carry Eurasian and African agriculturalist genetic material). This means that within the modern human metapopulation gene flow was sufficient to prevent incompatibilities from developing due to isolation. That being said, with the oldest (proto-)modern human skull dating to ~300,000 years, and likely discernible population structure between various African lineages going beyond 200,000 years ago, there are lots of distinct modern human groups with very long histories within Africa and on its periphery.

The earliest point that you could probably say non-African humans diverged from any African (Sub-Saharan) populations is ~100,000 years ago (and this is probably a bit too generous). A conservative estimate would suggest that modern human lineages were emerging within Africa 200,000 to 300,000 years ago. So most of modern humanity’s existence has been within Africa.

The non-African populations descend from a group which underwent a period of reduced population size vis-a-vis all the African groups. But one thing I think is important to remember is that this was probably not exceptional. We know now that over the past 5,000 years African population genetic structure has been reshaped by events such as the Bantu expansion. But there were surely small and marginal groups with low effective population sizes within Africa that either went extinct or were absorbed by other populations.

The difference in the non-African population is that it was on the edge of the modern human range, and likely occupied territory that was relatively isolated from other modern humans due to the dry nature of the Sahara during most of the Pleistocene. This prevented its absorption into more numerous groups of modern humans further south and to the west. And the strong cultural and genetic barriers with the Neanderthals probably limited gene flow as well.

But even in the inclement conditions of North Africa and West Asia for most of the past 100,000 years, modern humans may have had a larger effective population size than archaic Eurasian hominins. And with this larger effective population size, one can imagine that greater cultural creativity and genetic robustness to dynamics such as population declines gave the modern humans a long-term advantage. In this context, the existence of modern human remains in a diverse array of places across warmer areas of Eurasia before 60,000 isn’t that surprising. And, the demographic wave that swallowed Neanderthals and Denisovans probably swallowed the earlier modern humans who ventured into eastern Eurasia before 60,000 years ago!

Why general audience news will only get more ideologically polarized: propaganda pays the bills

Posted on by Razib Khan

During a casual conversation with a friend about the state of the “news media” and its openness ideological diversity I expressed my rather cynical view that the future of the mass-market journalism is toward one of polarization. The reason for this isn’t really due to the nature of journalism in any specific way, but the reliance of journalistic outfits on very distinct markets. Publications are now focused on gaining subscribers, and to gain subscribers you have to provide product people want.

People read news for various reasons. Titillation and curiosity obviously. But also for self-affirmation and confirmation. This is rather clear for cable news, but the same dynamics apply to print and internet. News is a consumption good. People aren’t going to want to hear it or read it if it doesn’t flatter their own self-image. So when push comes to shove on sensitive issues the media will provide its customers what they want.

To give a concrete example, in 2009 a genetics paper provided strong evidence that Indian populations were stratified in ancestry as a function of caste and region, and that one component of South Asian ancestry is intrusive from the West. To my surprise, Indian publications put forth stories like this: Aryan-Dravidian divide a myth: Study. Basically, the media were transmitting the opposite of the most plausible interpretation of the results.

At the time I mocked the Indian press for being propaganda and the Indian public for wanting to see what they wanted to see. To be entirely honest I wouldn’t do such a thing today because when in glass houses one shouldn’t throw stones. My views of my country and its elite classes of various professions have changed quite a bit in the past 10 years.

The American media is quite willing to provide propaganda if that’s what its paying public wants. To give a concrete and now non-partisan example: the American media allowed itself to launder misinformation in the lead-up to the second Iraq War. A few people were right, and they were ignored or derided.

And like Indian journalists and scientists, American journalists and scientists also have some preferences about what they want to be true, so it’s not as if they are kicked and dragging in the direction of their most congenial results.

The “best” thing about the game that the Indian media played, and the game that the American media plays, is that the people believe that the propaganda is actually fair and balanced! Even the journalists themselves may believe the propaganda because many of them lack specialized knowledge to know when the people they interview are lying to them or misleading them (the Gell-Mann Amnesia Effect is really disturbing).

Finally, if you are one of those people who strangely prefer the truth, there is a way you can get it: become wealthy and buy the truth. If you are running a hedge-fund or some such other thing, information is not just a passive consumption good. Information is input into the production of more wealth and power. People in this sort of results-driven financial sector mine informants for truth in a very conscious manner to maximize returns for themselves and their clients. And of course, there exists a market for what is basically “reality-based journalism”. It’s just a market that is invisible to us plebs unless we find ourselves having access to nuggets of truth which no one wants to hear, but which global capital wants to profit from….

The “media” that you see and hear about. The media with the big budgets and large news organizations are actually just a simulacrum of an objective data-gathering and transmission institution. In reality, they are tribal newsletters. On the narrow scale, they often reinforce particular tribal narratives and ignore countervailing ones. But on a broader national scale, they collectively flatter our self-image as a people in a sometimes ludicrous fashion.

The real objective data-gathering and transmission institutions are hidden from view. And they are the ones laundering the “truth” to those with power so that they may have more power.

Welcome to the future!

Our family’s pedigree in 23andMe

Posted on by Razib Khan


With 23andMe’s new update to its ancestry, the results for my family have changed. Not for me, since I’m not of European descent, and this looks Euro-focused (no surprise). But my wife and kids are different.

My wife has two great-grandparents who were born in Norway. 23andMe is picking that up immediately. It also picks it up in my children, from left to right, my daughter, my younger son, and my older son. With more than 3 million in their database 23andMe has knowledge of which haplotypes are unique to Norway, and which are not. When you click “Norway,” it says “We predict you had ancestors that lived in Norway within the last 200 years.” That’s telling me that they detect IBD segments uniquely found in Norwegian populations of a particular length threshold.

My youngest is on a new chip, so the Western Asian & North African I dismiss. But I’m not sure I believe some of the European admixture estimates. The two boys exhibit very little drop off in Scandinavian. But my daughter is way lower. This is not unreasonable, but they also exhibit differences in East Asian ancestry. And I’ve looked but I can’t detect this on PCA plots. My daughter is, in fact, more distant from Han Chinese than my sons.

In the future, I think perhaps genealogy-focused results, which show matches within particular nations, should be partitioned from admixture analysis. That’s how it used to be.

(it is a curious coincidence that both my more Scandinavian children are heterozygotes on the KITLG locus for the derived variant, though I know they get it from their mostly German grandfather)

The continuity of a people

Posted on by Razib Khan

From a comment below [edited]:

The Chinese and Egyptians are an interesting case in this because they had one of the earliest written scripts (or rather tradition across generations to impart and carry information) and it was spread over long surviving/thriving timelines.

But then Egyptians lost the linguistic capability and lost their history even though they had archaeological structures all around them.

Language IS Culture. Literally.

There is only so much oral tradition can do. Even if it survives the population scale that carrier it becomes smaller and smaller and the cultural pressures from the majority overwhelm or dilutes the narrative 1000 years later. This happened in India. People forgot/evolved their ancestry even if there were a gross minority of class who remembered their class’s origin myths in a certain way.

From a purely reductive and spare understanding of human flourishing, this is irrelevant trivia.

The destruction of the Bamiyan Buddhas was no great loss. They were stone. Carved by man. That might be a Benthamite view. It would be a Salafi view.

But most people don’t think this way.

One of the themes of Toby Wilkinson’s The Rise and Fall of Ancient Egypt is that the temple institutions persisted over thousands of years. Even as dynasties turned over, the temples maintained a link to the past. Though many of their cultural characteristics were disappearing by the time of Ptolemies the Egyptians of this period still exhibited continuity with their ancestors. The hieroglyphic system actually was used down to 400 AD. The last inscription is dated to 394 at the temple of Philae. Philae continued in operation down to the 6th century, before it was closed by Justinian.

Other documents indicate knowledge of the hieroglyphic system into the 5th century AD. But the destruction of the old temples, the old customary religion, was the death of the old history and identity.

The Chinese continuity is striking because it is true that down the last years of Imperial China in the early 20th century the literati could access the entire corpus of Chinese though back 2,000 years. Dynasties fell, but unlike the West, there was no rupture with antiquity.

The case of India is interesting because I would argue Hindu Indians have maintained continuity with the civilization of India as it had matured in the centuries around the invasion of Alexander the Great. The Brahmins have maintained Vedic texts and the Sanskrit language. Those from the Abrahamic traditions sometimes contemptuously refer to Hinduism as “pagan,” but there is some truth in this, insofar as the religion grew and accrued itself organically from the native cultural traditions.

Today China is promoting “Confucius Institutes” as part of its “soft power.” Chinese who lived in the late 1960s would find this very strange, as they had abolished Confucius and were overturned the culture, the civilization, of China. But such tumult is not sustainable. I wonder if we are going through the same thing in the West. If so, perhaps we too will be promoting Plato institutes a generation from now?

When America is no longer the world

Posted on by Razib Khan

On this week’s Slate Money the author of The Big Picture: The Fight for the Future of Movies, was a guest. I’m not going to be reading this book, but it seemed interesting. Basically, he suggested that the reason franchise movies, and in particular comic book films, were taking over is that television has taken over niches such as period dramas. The comparative advantage of the movie theater is in big-budget action & special effects spectacles, and audiences enjoy revisiting “shared universes” so much that they’re far less risky than singletons.

This shouldn’t be surprising, there’s a reason that standalone fantasy books are not notable.

An issue that is discussed on the podcast is the fact that international blockbusters tend to be American. China tried to produce something that would be exportable to the USA with The Great Wall, but it was a bust.

It strikes me that when American movies no longer dominate internationally, that’ll be a good sign that true dusk is coming to our time as the global hegemon.

Open Thread, 4/2/2018

Posted on by Razib Khan

DNA tests for IQ are coming, but it might not be smart to take one. I talked to Antonio about this piece a few times. I didn’t have much to say with any insight. These tests aren’t ready for primetime because the prediction is pretty weak/worthless.

With a lot of this stuff realized phenotype is what matters. If I took a test and it said my predicted IQ was 90, or if I took an IQ test and it said that I was in the 15th percentile from the bottom, I wouldn’t reconsider whether I’m dumber than most people seem to think I am. I’d think that the tests were dumb.

Like genetic screening more generally this sort of stuff will become more important for newborns in the future because you don’t have a realized phenotype. Siblings different in intelligence. Some of this is random, but some of it surely dependent on genes. If children have different talents or competencies I suspect many parents will want to know as early as possible (my two oldest are young, but it’s already pretty obvious that my son is much stronger on visuospatial skills while my daughter has a better ability to abstract in a general sense).

Ancient DNA tracks the mainland extinction and island survival of the Tasmanian devil. The main issue I have with all these studies is the importance they put on climate. Climate changes. Often. That’s usually not a sufficient condition for extinction. People and the animals they bring around are.

I guessed that the supplements shirt would not be popular, judging by how many questions I get that would be answered by reading the supplementary text!

That being said, I bought one for myself. Of course, I would! (I’m going to post a photo of me wearing it when I get)

A Financial Times story about the Kalash. I filled in some dumb surveys and it allowed me to read for free. It’s a pretty good story.

When Gmail Launched On April 1, 2004, People Thought It Was A Joke. I’m starting to worry about our reliance on platforms. And that includes Gmail.

How to Talk About ‘Race’ and Genetics. David Reich responds in The New York Times.

There has been a lot of talk on “science Twitter” about the David Reich situation. Some of it in public. And some of it in private DMs. I am heartened personally to see that most people are defending him because he does not deserve the patronizing abuse that’s being directed at him.

I am not much in touch with David, though we have met in person, and exchanged a few emails about his work. It’s not breaking any confidence for me to say that he did not write Who We Are and How We Got Here to become famous. The book will sell well, but it’s not written in a manner that will make him rich. In any case, among his peers, he is already quite famous after all. As he noted in the introduction to Who We Are and How We Got Here he wrote it to speak to those outside of the community of human population geneticists who read and write scientific papers.

Since David has such a high-status people within the community are very careful about what they say about him if they have strong criticisms. Not only is it hard to argue that he’s ignorant of the science (after all, he is one of the major producers of science!), but he’s a powerful figure embedded in a powerful institution.

This is why when you examine the list of 60+ signatories to this op-ed in Buzzfeed, How Not To Talk About Race And Genetics, there are very few working geneticists on the list. I heard a rumor that there were actually a few genetic anthropologists willing to sign, but who didn’t agree with the final text and withdrew. And good for them, because this op-ed is a confused mess.

But, to be frank it’s entirely to be expected from a certain type of scholarship. Like many, I have expressed some concern and annoyance that geneticists engage in imperialism without consulting historians and archaeologists. But these are real disciplines with real facts and theories, whether those facts are undermined, and the theories shown to be false. There is something real to be grasped at. The Buzzfeed op-ed, in contrast, is by turns patronizing, incoherent, or just false.

The conversation has been bracing, but I’m not sure it’s moving toward any synthesis.

Complex traits are probably subject to Kurzweil’s The Law of Accelerating Returns. Stuff is moves slow, then faster, and then we’re slammed against a new world before we can adjust.

Here’s a poll I created:

Detecting signatures of positive selection along defined branches of a population tree using LSD. The day will come when ancient DNA papers will start to slow down in their rate of release and I’ll have to catch up on the selection literature (though to be fair, there’s only so many real targets of selection we’ll pick up).

Comparison of Genotypic and Phenotypic Correlations: Cheverud’s Conjecture in Humans.

Back to reading Enlightenment Now.

Excited that the AAPA meeting is happening in a few weeks in Austin. Will be meeting up with a few people.

When do people forget where they come from?

Posted on by Razib Khan

When it comes to the arrival of Indo-Aryans to South Asia a major question Indians always post is “if they are invaders why don’t they mention that in their mythology?” My standard rejoinder is straightforward: we have plenty of paleogenetic evidence that many populations are intruders, but their mythology doesn’t indicate that. If the Indian objection is to hold then why not others? Are all human populations autochthonous in their native lands?

And yet the most recent work suggests that steppe ancestry didn’t arrive in the BMAC region until 2000 BC. That means that the Cemetery H culture in Punjab dating to 1900 BC is the earliest likely candidate for Indo-Aryans in South Asia. The Rigveda was composed as early as 200 years after this date, or as late as 700 years. Could they have “forgotten” where they came from?

The Irish are one people who have preserved their mythology due to the gradual and indigenous nature of Christianization. But 2,500 years after their arrival en masse from the continent they had forgotten the details. But, the motif of invasion was preserved, though we don’t know if that is a memory of their past, or just a channeling of the mythos of the period when their folklore was written down. Another example might be the Japanese, who arrived about 1,100 years before the Heian period, the first flowering of literate civilization on the island. To my knowledge, their mass migration from southern Korea was mostly forgotten by then.

With all this in mind, I decided to reread Genetic origins of the Minoans and Mycenaeans. The conclusion of the paper is that it’s clear an appreciable, though minority, component of Mycenaean ancestry seems to have some affinity with Indo-European groups. The two candidates for the donors are people from the Eurasian steppe, or Copper age Armenians. For linguistic reasons that I can barely evaluate, I lean toward the former. This implies that the proto-Greeks arrived in the late 3rd millennium or early 2nd millennium. The mythology of ancient Greek as recorded by Hesiod and others in the Archaic period probably dates in part to the Bronze Age (some of the Greek gods are recorded in the Linear B tablets). To my knowledge the Greeks do not record when they arrived from outside of Greece.

This suggests that 1,000 years is sufficient for a forgetting, at least for a semi-literate society.

The last is key. Societies with written histories can maintain continuity. But what about oral societies?