I haven’t personally asked to get a copy because, to be honest, I thought there wouldn’t be anything new in it. If you “read the supplements” what more could there be in 368 pages? So I was waiting until the end of the month to buy the book and read it in my own sweet time as due diligence.
Well, this morning I asked a publicist to send me a copy. I will be getting it next week. The reason is that I’m told the latter portions of the book are quite challenging and candid as to what genetics may tell us in the 21st century. Who We Are and How We Got Here is a 21st-century revision and update of The History and Geography of Human Genes. But it’s apparently a lot more.
Also, I make a small cameo in the book, as does Eurogenes and Dienekes. I have always appreciated how the David Reich and Nick Patterson and their whole lab has taken people outside of the halls of the academy seriously. They didn’t need to as a matter of professional necessity but often engage as a matter of decency and seriousness.
In the 1970s Richard C. Lewontin wrote about how the allozyme era finally allowed for the testing of theories which had long been perfected and refined but lay unused like elegant machines without a task. Almost immediately the empirical revolution that Lewontin began in the 1960s kickstarted debates about the nature of selection and neutrality on the molecular level, now that molecular variation was something they could actually explore.
This led to further debates between “neutralists” and “selectionists.” Sometimes the debates were quite acrimonious and personal. The most prominent neutralist, Motoo Kimura, took deep offense to the scientific criticisms of the theoretical population geneticist John Gillespie. The arguments around neutral theory in the 1970s eventually spilled over into other areas of evolutionary biology, and prominent public scientists such as Richard Dawkins and Stephen Jay Gould got pulled into it (neither of these two were population geneticists or molecular evolutionists, so one wonders what they truly added besides bluster and publicity).
Today we do not have these sorts of arguments from what I can tell. Why? I think it is the same reason that is the central thesis of Benjamin Friedman’s The Moral Consequences of Economic Growth. In it, the author argues that liberalism, broadly construed, flourishes in an environment of economic growth and prosperity. As the pie gets bigger zero-sum conflicts are attenuated.
What’s happened in empirical studies of evolutionary biology over the last decade or so is that in genetics a surfeit of genomic data has swamped the field. Some scholars have even suggested that in evolutionary genomics we have way more data than can be analyzed or understood (in contrast to medical genomics, where more data is still useful and necessary). Scientists still have disagreements, but instead of bickering or posturing, they’ve been trying to dig out from the under the mountain of data.
It’s easy to be gracious to your peers when you’re rich in data….
The major core finding is that ancient DNA along with better data from extant species suggests that straight-tusked elephant of Europe(P.antiquus), which went extinct 50,000 years ago, seems to have been an evolutionary synthesis of sorts. A substantial portion of its ancestry as from a deeply diverged lineage of elephant. But another fraction seems to derive from a branch of the African forest elephants, in particular, the West African variety. Finally, earlier on there was also admixture with an Asian pachyderm related to the woolly mammoth.
You can see from the figure at the top that the divergence between these lineages is on the order of hundreds of thousands to millions of years.
This section from the conclusion is a huge takeaway:
Our genomic analyses of present-day and extinct elephantids revealed a history of multiple major interspecies admixture events. Evidence for gene flow among closely related mammalian species is not unprecedented. Examples include cases of unidirectional gene flow [e.g., from polar bears into brown bears (47), similar to the Columbian mammoth gene flow into woolly mammoths observed in our study]; emergence of admixed species [e.g., North American wolves with ancestry from coyotes and gray wolves (48), similar to the straight-tusked elephants in our study]; different extents of gene flow [e.g., between gray wolves and Eurasian/African golden jackals (49), and between bonobos and central/eastern chimpanzees (50), as in the case of straight-tusked elephants and west African forest elephants/woolly mammoths in our study]; extended periods of gene flow during the initial diversification of species [e.g., between eastern and western gorillas (39), Sumatran and Bornean orangutans (39), and the ancestors of humans and chimpanzees (39, 51), like those inferred from most pairwise species comparisons in our study]; and adaptive introgression [e.g., in the great cats of the genus Panthera (52)], which could have played an important role in the evolution of elephantids as well. Our results in elephantids thus add to the growing weight of evidence in favor of the view that capacity for hybridization is the norm rather than the exception in many mammalian species over a time scale of millions of years.
Big speciose mammal lineages seem to have hybridzed a lot. Should this surprise us? Probably not.
A central question in evolutionary biology is why animal lineages differ strikingly in rates and patterns of the evolution of reproductive isolation. Here, we show that the maximum genetic distance at which interspecific mammalian pregnancies yield viable neonates is significantly greater in clades with invasive (hemochorial) placentation than in clades with noninvasive (epitheliochorial or endotheliochorial) placentation. Moreover, sister species with invasive placentation exhibit higher allopatry in their geographic ranges, suggesting that formerly separated populations in mammals with this placental type fuse more readily on recontact. These differences are apparently driven by the stronger downregulation of maternal immune responses under invasive placentation, where fetal antigens directly contact the maternal bloodstream. Our results suggest that placental invasiveness mediates a major component of reproductive isolation in mammals.
Monkeys and apes (including humans), have very invasive placentas. Afrotheria, somewhat less so. Placental invasiveness isn’t the only criteria to predict or gauge the viability of hybridization, but it’s a major one.
I’ve stated before that genomics didn’t really change our understanding in a qualitative way in relation to evolutionary biology. Yes, stupid arguments about selectionism vs. neutralism really don’t happen anymore because there’s a mad scramble for data, as opposed to rhetorical tactics. But, perhaps in the area of understanding speciation with regards to mammals genomics has really changed things. That is, it’s a lot more about reticulation and a lot less about bifurcation.
To a great extent the “biological species concept” (BSC), which to the general public is the scientific species concept, is mammal focused. If plant geneticists had the catbird seat I think we’d have a different view of what species were. As it is, that’s not what happened. Species are human constructs and reify a certain Platonic sense of categories and kinds. What genomics is showing us here is even in the “best case” circumstances of the BSC, in mammalian lineages, when evaluated over reasonable time spans species barriers are highly porous.
I periodically check up on Amazon’s monthly deals. Though the science section is usually pretty thin, the history deals are more numerous. A lot of them are not too good, or are reprints of very old books. But now and then you get a scholarly and dense work which is magically priced at below $2.00.
I will say it’s strange to see how many people really hate the book (presumably without reading it?) and hate Steven Pinker. And curiously, it’s a pretty broad and ecumenical hate, from the respectable Left to the respectable Right. There is also more measured criticism on the merits from academics.
Land of Promise, by Michael Lind, is a book I’ve mentioned several times. It is broadly within the mainstream “big government Left.” But, I don’t think I’ve observed that it ended on a curious note. It used the term “chain migration” and argued for a shift toward skilled migration. Lind also asserts that low skill immigration pushes down wages of low skill Americans.
Land of Promise came out in 2012. The 2008 financial crisis looms large. But we’ve moved a lot when it comes to immigration even since then… Not sure if the editors would let Lind leave that section in if he was writing today because it’s pretty much consonant with Donald Trump’s positions.
* Brian Wansink is a “good person” by normal definitions.
* His ultimate aim as a scholar is something most people would agree with. That is, he wants people to eat healthier.
* Any single aspect of his behavior in this article, p-hacking, recycling papers to lower ranked journals, sloppiness, and trying to get the media to pay attention to his research, is not that exceptional. It’s the magnitude and synergistic complementation.
* There are serious issues with the incentives for academics today, whether it be within the field (quantity of publications as opposed to quality), and the media (publish stuff that the media wants to believe).
The Wansink affair is a really great illustration of the symptom. But the structural problems are still there.
Tania gets a lot of space in Graeme Wood’s The Way of the Strangers: Encounters with the Islamic State, but she’s apparently writing her own book. I’m pretty curious, because Tania and I have a lot in common, but are also different in many ways. She grew up in a British Bangladeshi household, and one of the major things she mentions in the interview is how oppressively capricious and controlling her parents were. To be honest I related to this…but as a male, I’m sure my experience was much milder. Additionally, British Muslim communities are isolated and regressive in a way that American Muslim communities never are (in fact, outside of a few places like Hamtramck, Michigan, there aren’t American Muslim communities as such). That also comes through in what Tania says.
Spencer wrote a blog post today which is worth checking out, R.I.P. Great Leap Forward, which reflects his own historical progression and understanding on this topic. Our podcast with Chris Stringer should be up Wednesday night (so subscribe), and we touched on this somewhat (it was recorded before the paper landed, though Chris already knew about it). We’ll be talking to Milford Wolpoff this week, so we’ll see what he thinks.
One thing I want to mention offhand. Back in the 2000s, I had some online exchanges with “Mencius Moldbug”. They weren’t exactly hostile, but ultimately I dismissed him because he got a lot of details wrong. And, to be honest, I was kind of annoyed by his stupid cultists who would leave comments. Moldbug himself was and is a smart guy, but some of his acolytes were not.
In 2018 I do have to say that I think that though Moldbug was wrong on a lot of details, and still is, he had insight into something more general which I lacked. My deep pessimism about bourgeois liberal democratic civilization and the state of intellectual culture draws from the same well that he drew from, though I disagree on a lot of the details to this day (I also now am much more open to radical Leftist critiques as well).
I bring this up partly because one of the things that convinced me to ignore Moldbug was his rejection of data which conflicted with his priors. For about 10 years it has been rather obvious to me looking at the literature and my own data analysis that most ancestry in Southern Italy and Sicily does not derive from migration from the east which dates to Roman antiquity.
The blogger at Eurogenes has posted the result from a Sicilian Bell Beaker individual. You can see that modern Sicilians are shifted away from the Bell Beaker Sicilian, who is more skewed toward the EEF cluster. But it’s pretty obvious that the shift has not been predominant. Modern Sicilians tend to have some ancestry which is certainly North African, and perhaps Greek. And the Sub-Saharan African in some individuals, which probably arrived during the Islamic period, is hard to miss. But most of their ancestry seems to date to before the Roman period.
And Sicily is the “best case” for predominant replacement in Italy.
DNAGeeks is now selling a Neanderthal shirt which honors their artistic abilities.
I put a poll up on Twitter asking about the species status of Neanderthals. I am a lumper, so I’m between two and three.
It’s kind of weird that people are explaining that there are “species concepts” to me in the comments. I thought answer 3 makes it pretty clear I’m aware of that.
I watched Black Panther. I liked it. It looks like it will make a lot of money. I wouldn’t be surprised if it results in copy-cat films. They probably won’t make a lot of money because they won’t be good films, and then Hollywood will go back to doing what it always did.
Also, I found out that there’s another Mission Impossible film. Tom Cruise is the new Dick Clark of our era.
Apparently, there isn’t a character for the word “problematic.” That’s good.
But I’m reading Judith Butler’s Gender Troubles soon. You might find that strange, but I’ve read Christian and Muslim apologetis too.
The above doesn’t capture the subtlety of Gat’s book, and I’m pretty sure it doesn’t capture that of Anderson’s either. But, those are the caricatures that people take away and project in public, especially Anderson’s (since Gat’s is not as famous).
When it comes to “imagined communities” I recently have been thinking how much that of modern Turks fits into the framework well. Though forms of pan-Turkic nationalism can be found as earlier as 9th-century Baghdad, the ideology truly emerges in force in the late 19th century, concomitantly with the development of a Turkish identity in Anatolia which is distinct from the Ottoman one.
The curious thing is that though Turkic and Turkish identity is fundamentally one of language and secondarily of religion (the vast majority of Turkic peoples are Muslim, and there are periods, such as the 17th century when the vast majority of Muslims lived in polities ruled by people of Turkic origin*), there are some attempts to engage in biologism. This despite the fact that the physical dissimilarity of Turks from Turkey and groups like the Kirghiz and Yakut is manifestly clear.
Several years ago this was made manifestly clear in the paper The Genetic Legacy of the Expansion of Turkic-Speaking Nomads across Eurasia. This paper clearly shows that Turkic peoples across Eurasia have been impacted by the local genetic substrate. In plainer language, the people of modern-day Turkey mostly resemble the people who lived in Turkey before the battle of Manzikert and the migration of Turkic nomads into the interior of the peninsula in the 11th century A.D. Of course, there is some genetic element which shows that there was a migration of an East Asian people into modern day Anatolia, but this component in the minority one.**
Sometimes the Turkish fascination with the biological comes out in strange ways, Turkish genealogy database fascinates, frightens Turks. Much of the discussion has to do with prejudice against Armenians and Jews. But the reality is that most Turks at some level do understand that they are descended from Greeks, Armenians, Georgians, etc.
To interrogate this further I decided to look at a data set of Greeks, Turks, Armenians, Georgians, and a few other groups, including Yakuts, who are the most northeastern of Turkic peoples. The SNP panel was >200,000, and I did some outlier pruning. Additionally, I didn’t have provenance on a lot of the Greeks, except some labeled as from Thessaly. I therefore just split those up with “1” being closest to the Thessaly sample and “3” the farthest.
The above tweet captures the essence of something that occasionally happens in science: a revelation that transforms our understanding of the possibilities of the real. 2010’s Neanderthal genome paper did that, transforming a field which was mostly skeptical or cautious of Neanderthal gene flow into modern lineages, to one that was accepting of the likelihood.
The team found flowstones covering parts of the artworks and scraped away samples for dating. In three caves, it turned out, some of the art was over 64,000 years old — about 20,000 years earlier than the first evidence of modern humans in Europe.
“They must have been made by Neanderthals,” said Dr. Pike.
Wil Roebroeks, an archaeologist at Leiden University who was not involved in the new study, said the evidence was conclusive. “This constitutes a major breakthrough in the field of human evolution studies,” he said. “Neanderthal authorship of some cave art is a fact.”
The colored, pierced shells themselves are probably not much older than that. Up until about 118,000 years ago, the cave was flooded, thanks to higher sea levels.
That finding provides strong evidence that the shells were made by Neanderthals. They were definitely living in Spain 115,000 years ago, while modern humans would not arrive in Europe for another 70,000 years.
The two new studies don’t just indicate that Neanderthals could make cave art and jewelry. They also establish that Neanderthals were making these things long before modern humans — a blow to the idea that they simply copied their cousins.
What to make of this? First, a shout out to my old friend John Hawks. He’s been slowly repairing the reputation of Neanderthals for many years, and now we’re almost there. Neanderthals had large brains. Their cranial capacities were the largest of all hominins. The idea that they were brutes without language, as Richard Klein hypothesizes in Dawn of Human Culture, seems ludicrous now.
Back in the early 2000s I read Stephen Oppenheimer’s The Real Eve, and one of the arguments that I thought was ludicrous at the time is that the dominance of African humans was not due to some distinct genetic advantage (as Richard Klein posited), but accumulated cultural capital which gradually but continuously compounded over time. Though one shouldn’t discount genes, especially in the context of gene-cultural coevolution, with hindsight it seems clear that a simple causal factor of genetic innovation driving advantages vis-a-vis Neanderthals may be too simplistic.
Papers such as Genomic insights into the origin of farming in the ancient Near East illustrate that first mover advantage can result in huge demographic consequences. Small groups of farmers in the hillocks of the Fertile Crescent 10,000 years ago transitioned to agriculture just early enough that their genetic impact on West and South Eurasian populations, as well as African ones, would be enormous. Similarly, the invention of the light chariot by the Sintashta people may have resulted in the spread of haplogroup R1a-Z93.
It’s been a big week for “Cheddar Man” and the science around him. I already talked about the issue blog-wise for my day job. Additionally, Spencer and I did a podcast on the topic (if you haven’t, please subscribe and leave positive reviews and ratings on iTunes and Stitcher; next we’ll post our conversation with Chris Stringer, don’t miss it!).
So at this point I’ll put some other thoughts here that are “big picture.”
Cheddar Man may have been black but probably wasn’t
Much of the media is focused on the predicted pigmentation of Cheddar Man. That is, dark. Back when the La Brana Western Hunter-Gatherer results came in with the same finding, several population genomics people pointed out that it might not be valid to predict their phenotype based on modern training sets.
Here are some thoughts:
Cheddar Man and the WHG in general were probably darker than modern Northern Europeans. There is detectable selection in modern Europeans for pigmentation alleles down to the present, and Northern Europeans are the palest people in the world. And, pigmentation is polygenic, but it’s not hyperpolygenic. That’s why GWAS and early selection tests picked up pigmentation loci as hits so often.
Cheddar Man and the WHG in general were probably not as dark as tropical people. The only people who live(d) at very high latitudes who were very darkly complected were Tasmanian Aboriginals and Australian Aboriginals (Melbourne is at the same latitude south as Lisbon is north). In contrast, we see that Khoisan are brown, sometimes rather lightly so, while the peoples of non-European heritage who live in high latitudes are not dark-skinned, though they are not as light-skinned as Europeans.
We don’t have a time machine, so we won’t know with finality. But, it seems that pigmentation pathways are finite, and eventually we can probably be more confident if Cheddar Man had a genetic architecture that would lead to fewer and smaller melanocytes.
The First Farmers replaced WHG to a great extent in Britain
The preprint that came out with the Cheddar Man documentary really focused mostly on the Neolithic farmers. The data set was large, and it emphasized that the discontinuity between the farmers, who were EEF from Anatolian stock (modern Sardinians are their best proxies), the hunter-gatherers. WHG is genetically homogeneous, so they couldn’t reject the proposition that there was no admixture of British hunter-gatherers into the farmer population Basically, the thesis that Peter Bellwood outlined in First Farmers is well supported by these results. The farmers brought agricullture, and pushed aside or absorbed the hunter-gatherers.
It is notable to me that they found more hunter-gatherer ancestry (possibly) in eastern and northern populations, but not much in farmers from Wales. Additionally, though they couldn’t be definitive about it, the EEF settlers of Britain seem to have more affinities with the Western Mediterranean populations than the Central European ones. This suggests that perhaps the farmers arrived by sea or coast-hugging from the south and west, rather than from the south and east.
The arrival of farming to Britain was different
Farmers came to Britain later than to the continent. The shift from hunter-gatherer to farming was rapid. One model for why there was lack of admixture is that the farming cultural package was fully adapted to Northern Europe by the time they began settling the island. In contrast, on the mainland farmers were changing a Middle Eastern lifestyle into something that could take root in cold northern climes where there were already local residents.
Sometimes cultural and ecological changes drive rapid expansions of human populations
Today Europe, and much of Western Eurasia, is characterized by isolation by distance dynamics between populations. What you see in the transition from the Mesolithic to the Neolithic, and later with the arrival of metal age populations (Bell Beakers), is that populations can turnover fast, and that rapid expansion and growth can result in homogeneity across huge distances and then sharp continuities across cultural divides. The classical example of this is that hunter-gatherers and farmers in Central Europe did not exchange much in the way of genes for centuries, and their between population variance accounted for ~10% of their pooled variance (this is what you see comparing Han and Europeans). Additionally, WHG and EEF are both relatively homogeneous, at least before the latter began to absorb WHG at different fractions across its range. WHG descends from a late Pleistocene expansion, after the Last Glacial Maximum. Similarly, the EEF expanded rapidly from its Anatolian point of origin.
Britons didin’t become Britons genetically until the Bronze Age
Ten years ago many people thought that Cheddar Man and his people were the ancestors of most of the people who lived in Britain today. At the same time as this preprint came out, the Bell Beaker paper was officially published. We now know that Britain went through two massive demographic transitions in less than 2,000 years, with on the order of a 90% replacement in a few centuries both times.
Why? Was this typical? Those are for a later post….
There are many debates about the period after the fall of the Western Roman Empire in the late 5th century. For example, did it “fall” in the first place? I believe that the concomitant p0litical, social, and economic changes do warrant that word. But another question concerns the “barbarians,” who were mostly German peoples (there are some exceptions, such as the Iranian Alans and the Huns, whose specific provenance is unclear). Were they ethnically and politically coherent? Were they even peoples?
The extreme stylized positions might be outlined as follows:
– The barbarians who filled the political vacuum after the collapse of the late Roman state were coherent preexistent ethnic and political entities of German origin who migrated en masse and engaged in a folk wandering.
– Though their original provenance may have been in bands of German warriors from specific tribes, but the time they appear on the stage of history as we understand it, the barbarians were in fact a motley crew of opportunists of various origins, who adhered to a “barbarian” identity which was created de novo with the collapse of Rome. They were made by the collapse, they did not cause the collapse.
In the late 1990s, Norman Davies in The Isles presents an argument closer to the latter for the British Isles. That is, the Anglo-Saxon character of Britain was to a large effect a function of elite emulation and diffusion of a Germanic culture introduced by what was operationally a late Roman mercenary class. Davies alludes to texts which indicate a substantial native British population in Anglo-Saxon England centuries after the fall of Celtic kingdoms. This is in contrast to the apocalyptic vision of British monk Gildas, who depicts his Brythonic people fleeing before pagan Saxons and being driven into the sea. And, I have alluded to the possibility that the West Saxon monarchy, which later came to the center of English history during the Viking incursion, was in fact in origin Romano-British, rather than German (the early kings have Celtic names).
And yet England was always the most difficult case for cultural diffusion, because to a great extent Roman-British society did collapse. Both the British Celtic language and Christianity seem to have faded from the landscape, so the that the latter had to be reintroduced by Irish and continental European missionaries. Today, the genetics is more definitive, and it seems a substantial German migration did impact what became England, especially the east, what was the Saxon Shore. Though the majority of the ancestry of the people of England today seems to derive from people who were already resident in Britain in 400 A.D., a substantial enough minority seems to have greater affinities to people who were living in the stretch of land between the Netherlands and Denmark.
The case for mass migration on the continent of Europe (with the exception of much of the Balkans) is more difficult to make in a cut & dried fashion because the basic outlines of Romanness were much more intact in the centuries after the fall than in Britain. Though France and Lombardy may have names which derive from German tribes, there is not much that is German about these regions today, and frankly, even at the height of the barbarian rule when conquest and migration were fresh, the non-Roman overlay was likely a thin elite layer. Outside of Britan and the Balkans, the languages of the Roman Empire and the Christian religion maintained their dominance even after the fall of the Roman political order, a transformation of social norms, and the collapse of the economy.
And yet this does not deny the possibility of migration of peoples into this order. In Empires and Barbarians: The Fall of Rome and the Birth of Europe the historian Peter Heather argues that we must not neglect the likelihood that to some extent the arrival of the Germans was one of “folk wanderings.” That the identity of the Franks, Goths, and Lombards, did not emerge ad hoc and de novo through the accrual of military men around a tiny nucleus of German warlords and their retainers. That women and children were also part of the movement into the Roman Empire. Heather, in fact, depicts the Gothic arrival as one of destitute refugees fleeing the famine and chaos outside of the Pax Romana, and their subsequent militarization and rebellion as one forced upon them by the exigencies of their situation.
Despite centuries of research, much about the barbarian migrations that took place between the fourth and sixth centuries in Europe remains hotly debated. To better understand this key era that marks the dawn of modern European societies, we obtained ancient genomic DNA from 63 samples from two cemeteries (from Hungary and Northern Italy) that have been previously associated with the Longobards, a barbarian people that ruled large parts of Italy for over 200 years after invading from Pannonia in 568 CE. Our dense cemetery-based sampling revealed that each cemetery was primarily organized around one large pedigree, suggesting that biological relationships played an important role in these early Medieval societies. Moreover, we identified genetic structure in each cemetery involving at least two groups with different ancestry that were very distinct in terms of their funerary customs. Finally, our data was consistent with the proposed long-distance migration from Pannonia to Northern Italy.
The preprint has genetic and isotopic results from two graveyards associated with elite Lombards of the 6th century. The one in late antique Pannonia would be in modern Hungary. The one in modern Italy is near Turin. The late 6th century was a time of tumult in the Roman Empire, as both Italy and the Balkans were subject to massive turnovers of the ethnic and political orders. The movement into Italy from the northeast was a typical one, prefigured by the Goths and other Germans before the Lombards.
From what I know, as far as German barbarians went, the Lombards were rather “raw” and non-Roman (in contrast, some tribes, such as the Goths and Franks, had had relationships with the Roman Empire for generations before they decided to take it over). Though they were nominally Christianized, and elite Lombards persisted in practicing pagan rituals in Italy down to the 8th century, over 100 years after their conquest of the peninsula.
The authors used a lot of “best of breed” methods with their large data set, but the ADMIXTURE plot really illustrates the result fine enough. The blue is associated with Northwest European ancestry (British and white Utah samples), red with Italian ancestry (Tuscan), and green(ish) with Iberian (Spanish mostly). The very light blue is 1K Genomes Finnish. Panel B is the graveyard in modern Hungary, and panel C is the one from northern Italy.
There is a strong correlation in the graves with those being of Northern European ancestry, and having high status via grave goods. The individuals also exhibited some segregation in the graves. Northern European ancestry and Southern European ancestry individuals were clustered together. The Pannonian individuals, whether Northern or Southern European, don’t seem to resemble ancient or modern Hungarians. The isotope analysis indicates that many of the individuals were highly mobile.
Finally, the data was robust enough to do a pedigree analysis. It looks like a lot of these individuals are related. If you look at the plots you can see groups with the label “Kindred.”
There is so much detail in the results that I won’t recapitulate. Just read the preprint and make sure to check out the supplementary text. What I will say is this.
The Lombard migration seems to have been a migration of people of Northwest European heritage into Southern Europe.
The migration occurred during the lifetime of some individuals. These were highly mobile individuals.
There were associated groups with the Lombards, who were genetically distinct, and likely of lower status. Their Southern European character is also distinct from the native population of Pannonia in the case of panel A.
The Lombards themselves had Northern European ancestry which was somewhat heterogenous (probably different tribes and ethnicities). The shift away from Finnish ancestry probably indicates sampling more from western and opposed to central Europe.
Admixture with the local populations and other post-Roman groups began early on.
The ethnocultural distinctiveness of the Lombards is clear from the textual evidence. The genetic data here confirm that in totality. But, The Geography of Recent Ancestry Across Europe, also highlighted a lot of deep population structure within modern Italy, and could not discern much impact of barbarian migration outside of the Balkans across their data set. Why?
It is rather clear that there were population declines across the West Roman Empire in the years after the Gothic Wars. If you read the textual evidence you imagine some sort of catastrophe going on. In human terms it was catastrophic. On the scale of economics, it was catastrophic. But in terms of population genetics, the long-term impact was not that extreme. The local population structure was not much altered because the Roman population base was so high that even a large decline did not induce bottleneck effects, and the German elite was also small enough it did not much perturb the underlying structure which had roots back to the period before the Roman Empire. Even in the first generations of Lombards in Italy, which is the Collego data set reflects, there was intermarriage between German people and others.
The demographic impact of the German migrations was huge on culture, politics, and economics. But it was not huge on population genetics.
It’s been a lot of cheddar the past few weeks. Or should I say Cheddar Man, the 9,150 year old Mesolithic subfossil from the area of Cheddar Gorge in England. This individual is important because it’s the oldest remain of such high quality found in Great Britain. And, in the late 1990s, as reported in Bryan Sykes’ Seven Daughters of Eve and elsewhere, the Cheddar Man subfossil was genotyped for mtDNA, the maternal lineage. There were, and are, lots of controversies about the validity of that result due to contamination being common in those early years of ancient genetics.
But today we have Cheddar Man’s whole genome. The preprint is finally out, and I’m digesting. Additionally, there has been a Channel 4 documentary, and a few weeks of media hype all around the implications of Cheddar Man.
This is an exciting time for genetics, history, and heritage. Since Britain is a major center of interest for these topics, it’s not surprising that Cheddar-mania has taken off. To mark this occasion DNA Geeks commissioned a design of Cheddar Man using Prince as a model. That might seem strange, but it probably is appropriate given Cheddar Man’s other-worldly and ambiguous appearance. You can get t-shirts and framed prints.
I’ll probably be posting about the Cheddar Man preprint, which really transcends Cheddar himself, tonight or tomorrow.