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Looking back: postscripts to five most-read posts
As 2021 slinks out the door, I’m looking back on my first 14 months of writing on Substack. In 2022, my longtime blog gnxp.com, on the other hand, will turn 20. There, I’ve spent plenty of time over the years reacting to news as it happens and papers as they’re published. But I’ve approached the Substack platform differently, with an eye more to creating evergreen overviews that might bear rereading, and an awareness that I get a chance here to contribute to the first draft of genomics-informed human population history. Looking back over my first 14 months of posts, I wanted to single out five popular pieces that have had interesting postscripts in the news, in the mainstream media or in academic papers since I hit send on those original posts.
They came, they saw, they left no trace was about the genetic history of the Italian peninsula, organized around the rise and fall of Rome. In it, I point out that the evidence from genetics is that there was no difference between Etruscans and Latins. A bit more than 6 months later, we now have a paper that confirms with a much larger sample size that the genetics of Central Italy were established around 1000 BC or earlier, with no difference irrespective of ethnolinguistic identity. The origin and legacy of the Etruscans through a 2000-year archeogenomic time transect:
The origin, development, and legacy of the enigmatic Etruscan civilization from the central region of the Italian peninsula known as Etruria have been debated for centuries. Here we report a genomic time transect of 82 individuals spanning almost two millennia (800 BCE to 1000 CE) across Etruria and southern Italy. During the Iron Age, we detect a component of Indo-European–associated steppe ancestry and the lack of recent Anatolian-related admixture among the putative non–Indo-European–speaking Etruscans. Despite comprising diverse individuals of central European, northern African, and Near Eastern ancestry, the local gene pool is largely maintained across the first millennium BCE. This drastically changes during the Roman Imperial period where we report an abrupt population-wide shift to ~50% admixture with eastern Mediterranean ancestry. Last, we identify northern European components appearing in central Italy during the Early Middle Ages, which thus formed the genetic landscape of present-day Italian populations.
This again confirms the heuristic that it usually only takes a few genomes to draw a safe conclusion. As long as there’s some population structure within a group, then one or two samples from that group can be informative about a vast swath of its genealogy (remember that you have over 1,000 great-great-great-great-great-great-great-great-grandparents, assuming no inbreeding). Adding more just increases certainty.
The ultimate price of costless gestures: 2020's 2,000+ excess black lives lost to murder. When I dashed this piece off one afternoon in late April, talking about the murder spike wasn’t common in the mainstream yet. I got private messages of the form “Wow, I can’t believe you dare talk about this.” My friends’ concerns were simple: all the powerful institutions of the intelligentsia, including the mainstream press, were still invested in the idea that there had been no breakdown in law and order in 2020, and that the imperfect police were quite dispensable. A concomitant climb in rates of violence was not congenial to the narrative, so coverage of the homicide spike was minimized.
Until they accepted that reality made narrative discipline impossible. A month after I wrote my Substack piece, The New York Times’ Ezra Klein did a podcast, Violent Crime is Spiking, Do Liberals have an Answer? Once the establishment belatedly decided to admit that what was happening was happening, apparently then it was okay to talk about it without worrying. America is a free country, we can say what we want, whenever we want… At least those of us who are already canceled…?
Ashkenazi Jewish genetics: a match made in the Mediterranean was one of my most popular posts. But, as my friend Josh Lipson mentioned during our podcast, I left a few fascinating things out. In particular, he pointed out that Ashkenazi Jews carry an mtDNA lineage that is likely from China:
Contemporary Jews retain a genetic imprint from their Near Eastern ancestry, but obtained substantial genetic components from their neighboring populations during their history. Whether they received any genetic contribution from the Far East remains unknown, but frequent communication with the Chinese has been observed since the Silk Road period. To address this issue, mitochondrial DNA (mtDNA) variation from 55,595 Eurasians are analyzed. The existence of some eastern Eurasian haplotypes in eastern Ashkenazi Jews supports an East-Asian genetic contribution, likely from [the] Chinese. Further evidence indicates that this connection can be attributed to a gene flow event that occurred less than 1.4 kilo-years ago (kya), which falls within the time frame of the Silk Road scenario and fits well with historical records and archaeological discoveries. This observed genetic contribution from Chinese to Ashkenazi Jews demonstrates that the historical exchange between Ashkenazim and the Far East was not confined to the cultural sphere but also extended to an exchange of genes.
The haplotype is M33c, and the map below shows that except for the Ashkenazi Jewish branch (M33c2) the others are in central to south China, among Han and some Chinese ethnic minorities:
The blue is a sister lineage in India. The Ashkenazi M33c seems to be a daughter lineage of a group of central-south Chinese haplotypes.
Also, I didn’t highlight 3-5% Sub-Saharan African ancestry in Jews in general dating to antiquity. No, really: The History of African Gene Flow into Southern Europeans, Levantines, and Jews. Unlike the case with the East-Asian mtDNA, this can’t be traced to a single event, but seems to apply to many groups across the Mediterranean and Near East, from Sardinians, to Ashkenazi Jews, to Iraq’s Mizrahi Jews. The implication is that there was a low but significant level of Sub-Saharan African admixture in Roman antiquity, but this heritage is so evenly distributed across the population it doesn’t jump out as distinct.
I’ve talked about Denisovans a fair amount in this Substack’s first full calendar year: in Here Be Humans and What happens in Denisova Cave stays in Denisova Cave... until now, and on the podcasts Maximilian Larena: the most Denisovan ones and Dragon Man ascending: two geneticists discuss the latest paleoanthropological discoveries. But if time and space had allowed, another not-to-be-missed recent paper looks deeply into the paleogenetics of the cave with new methods, The earliest Denisovans and their cultural adaptation:
Since the initial identification of the Denisovans a decade ago, only a handful of their physical remains have been discovered. Here we analysed ~3,800 non-diagnostic bone fragments using collagen peptide mass fingerprinting to locate new hominin remains from Denisova Cave (Siberia, Russia). We identified five new hominin bones, four of which contained sufficient DNA for mitochondrial analysis. Three carry mitochondrial DNA of the Denisovan type and one was found to carry mtDNA of the Neanderthal type. The former come from the same archaeological layer near the base of the cave’s sequence and are the oldest securely dated evidence of Denisovans at 200 ka (thousand years ago) (205–192 ka at 68.2% or 217–187 ka at 95% probability). The stratigraphic context in which they were located contains a wealth of archaeological material in the form of lithics and faunal remains, allowing us to determine the material culture associated with these early hominins and explore their behavioural and environmental adaptations. The combination of bone collagen fingerprinting and genetic analyses has so far more-than-doubled the number of hominin bones at Denisova Cave and has expanded our understanding of Denisovan and Neanderthal interactions, as well as their archaeological signatures.
Finally, even though it came out when I had only a fraction of the subscribers I do today, it’s notable that Applying IQ to IQ - Selecting for smarts is important brought this Substack its biggest single-day traffic spike yet. Sady, American society is turning against intelligence testing. For more, I’ll point you to two Freddie deBoer posts, Why Are We Pouring Money Into a Black Box? Why Are We Subjecting Our Young People to a Process with Such Little Transparency? Why Are We Risking Our Economy On It All? and Why the Fuck Do You Trust Harvard? The big lie in American society today is that standardized testing benefits the privileged, and therefore we should get rid of it. Indeed, tests probably do benefit the privileged…but they benefit the privileged far less than do other things, like recommendations, secondary-school quality, or grade point average. So that’s why high-minded people of privilege want to get rid of them. What’s the downside for them? Why wouldn’t they embrace another great costless gesture that can be packaged as a sop to the least economically privileged… who will most disproportionately bear its significant harms? Believe me, it is not lost on me that my social commentary posts are starting to have the depressingly familiar ring of a single, formulaic mad lib, recycled eternally.