Cosmopolitanism at the Roman Danubian Frontier, Slavic Migrations, and the Genomic Formation of Modern Balkan Peoples
https://www.biorxiv.org/content/10.1101/2021.08.30.458211v1?rss=1
Cosmopolitanism at the Roman Danubian Frontier, Slavic Migrations, and the Genomic Formation of Modern Balkan Peoples
Abstract
The Roman Empire expanded through the Mediterranean shores and brought human mobility and cosmopolitanism across this inland sea to an unprecedented scale. However, if this was also common at the Empire frontiers remains undetermined. The Balkans and Danube River were of strategic importance for the Romans acting as an East-West connection and as a defense line against "barbarian" tribes. We generated genome-wide data from 70 ancient individuals from present-day Serbia dated to the first millennium CE; including Viminacium, capital of Moesia Superior province. Our analyses reveal large scale-movements from Anatolia during Imperial rule, similar to the pattern observed in Rome, and cases of individual mobility from as far as East Africa. Between ca 250-500 CE, we detect gene-flow from Central/Northern Europe harboring admixtures of Iron Age steppe groups. Tenth-century CE individuals harbored North-Eastern European-related ancestry likely associated to Slavic-speakers, which contributed >20% of the ancestry of today's Balkan people.
Samples from the Slavic cluster:
| Genetic Cluster | ID | Necropolis | mtDNA haplogroup | Y-chromosome haplogroup |
| Serbia_Slavic | I15537 | Timacum Minus, Kuline Necropolis | H13a2a | E1b1b1a1b1 |
| Serbia_Slavic_o | I15538 | Timacum Minus, Kuline Necropolis | H1e1a6 | R1b1a1b1a1a2f |
| Serbia_Slavic_o | I15539 | Timacum Minus, Kuline Necropolis | H1e1a6,H1e1a6 | R1b1a1b1a1a2f |
| Serbia_Slavic | I15540 | Timacum Minus, Kuline Necropolis | J1b1a1 | .. |
| Serbia_Slavic | I15541 | Timacum Minus, Kuline Necropolis | K1a4 | I2a1a2b1a1 |
| Serbia_Slavic | I15542 | Timacum Minus, Kuline Necropolis | H9a | I2a1a2b1a1 |
| Serbia_Slavic | I15543 | Timacum Minus, Kuline Necropolis | H1f+16093 | J2a1a(xJ2a1a1a2,J2a1a1b3,J2a1a4) |
Comments
Finding working models in qpAdm is tricky and often the models are being rejected for purely technical reasons, like poor quality, low sample size etc.
It can be Z645*, Z283* or Z93 (SZ1 has similar position on the NE PCA) so we need to wait for the bam files.
I've been running some qpWave models (essentially its the same as qpAdm but just estimates number of ancestry streams *not* admixture weights and feasible). Those have been finding that if I model present day European populations, using only as pRight outgroups(Mbuti, Turkey_N, Russia_Afanasievo, Serbia_IronGates_Mesolithic, Nganasan) , they have to have *exactly* the right level of mixtures of ancestry to have a passing p-value as each other. E.g. Belarusians only having passing p-values as Ukrainians, and Basques only as Spanish_North, Norwegians only as Icelandic, Czechs only with English, etc. Even populations who have relatively slight differences like Belarusians vs Norwegians or Scots (former slightly more WHG, latter slightly more Yamnaya and EEF) fail to have passing p-values.
So sometimes you can get the opposite problem to bad data, if you model has very good data (like high quality modern data) where a close match is rejected because the model is looking for very specific combinations.
(On a tangent, swapping in Bronze Age outgroups for the above - which are less sensitive to deep ancestry but more to the other drifts that separate east vs west europe - has roughly the same results, still very specific, but improves the degree to which East or Western Europeans can be modelled with other populations from East or West, while starting to reject things like modelling Czechs with English. And specifically seemed to improve the p-value of modelling Czechs with modern Carpatho-Balkan groups more than modelling them with NE).
If they don't pass as each other that's actually good. It means that qpAdm with this set of outgroups can distinguish between the target/left pops.
What's problematic is that when you change right pops everything can change. And you never know if the current right pops set is able to really set apart all the left pops or there is something missing.
"Luckily it's a preprint, so there's room for improvement."
I don't mean to discourage.
But 'experts' in genetics have a habit of keeping their heads in their asses so deep that they can't hear people explain their mistakes.
They're not going to listen to bloggers even though we know better. No one in their field of study will correct them.
It's complicated. It's not the oldest one, but it has an excess of this drift likely due to a recent admixture from a population that was also directly ancestral to the Baltic_BA cluster.
It's not the absolute age that is important here, but the fact that it predates CWC by a few centuries and it doesn't show any additional EHG or CHG ancestry, so it's not a badly dated or contaminated sample.
You underestimate how much work is needed just to "introduce" them. You've asked me now to write a huge paper about the paleolithic and mesolithic history of West Eurasia.
But the matter of this "Slavic" Etruscan is interesting.