Like three peas in a pod

One of the most interesting questions still waiting to be answered by ancient DNA is where exactly did the ancestors of the present-day European and South Asian bearers of Y-haplogroup R1a part their ways? Indeed, the answer to this question is likely to be informative about the place and time of the split between the Balto-Slavic and Indo-Iranian language families.

I was doing some reading today and discovered that the peoples associated with the Bronze Age Fatyanovo-Balanovo and Unetice archeological cultures shared strikingly similar metalwork, despite being separated by well over two thousand kilometers of forest and steppe. Apparently, this similarity is especially pronounced in the metalwork of the Unetice culture from what is now Slovakia (see Ancient Metallurgy in the USSR: The Early Metal Age, page 136).

S11953 is currently the only sample from Slovakia associated with the Unetice culture (Sirak et al. 2020). There are no Fatyanovo-Balanovo samples available yet. However, as far as I can tell, I0432 from Samara, Russia, should be a decent stand in (Mathieson et al. 2015).

Of course, both S11953 and I0432 belong to Y-haplogroup R1a. Moreover, S11953 belongs to a typically Balto-Slavic subclade of R1a, while I0432 belongs to a closely related subclade that is dominant nowadays among the Indo-Iranian speakers of Asia.

S11953 is younger than I0432, but this doesn't necessarily mean that his ancestors arrived in East Central Europe from deep in Russia during the Bronze Age. Indeed, the opposite is more likely to be true. That is, I0432 is probably the recent decedent of migrants from somewhere near the North Carpathians, because he shows elevated European Neolithic farmer ancestry compared to earlier ancients from the Samara region (see here).

Below is a Principal Component Analysis (PCA) showing how S11953 and I0432 compare to each other in the context of ancient West Eurasian genetic variation. Obviously, they're sitting in the same part of the plot, which suggests that they harbor very similar ratios of ancient genetic components and probably share relatively recent ancestry. The relevant PCA datasheet is available here.

I've also highlighted myself, Davidski, on the plot. That's because I share the same Balto-Slavic-specific subclade of R1a with S11953 and, in terms of overall ancestry, I'm similar to both S11953 and I0432. Moreover, I'm the speaker of Polish, which is a Balto-Slavic language. What are the chances that we're dealing here with a remarkable string of coincidences? Indeed, was the North Carpathian region perhaps the homeland of the language ancestral to both Balto-Slavic and Indo-Iranian?

However, please note that there's nothing unusual or remarkable about my ancestry. The vast majority of people of Central, Eastern and Northern European origin - that is, mostly the speakers of Balto-Slavic, Germanic and Celtic languages - would also land in this part of the plot.

See also...

On the doorstep of India

Y-haplogroup R1a and mental health

The mystery of the Sintashta people

On the association between Uralic expansions and Y-haplogroup N

Almost all present-day populations speaking Uralic languages show moderate to high frequencies of Y-chromosome haplogroup N. I reckon there are two likely explanations for this:

- the speakers of Proto-Uralic were rich in N because they lived in an area, probably somewhere around the Ural Mountains, where it was common, and they spread it with them as they expanded from their homeland

- Uralic languages often came to be spoken in areas of North Eurasia where N was already found at moderate to high frequencies

The major exception to this rule are Hungarians, whose language belongs to the Ugric branch of Uralic. Their frequency of N is close to zero and they don't differ much in terms of overall genetic structure from their Indo-European-speaking neighbors in East Central Europe.

This is an issue that has generated much debate over the years about the nature of Uralic expansions, who the Hungarians really were, and how the Hungarian language came to be spoken in the heart of Europe.

But I never understood what the fuss was about, because based on historical sources alone it seemed rather obvious that Hungarian was introduced into the Carpathian Basin during the Middle Ages by a relatively small number of invaders from the east, probably from somewhere around the Ural Mountains, who imposed it on local Indo-European-speaking populations.

As far as I can remember, this has always been the academic consensus, and the results from one of the first ancient DNA studies of human remains soundly corroborated it. Back in 2008, Csányi et al. reported that two out of four skeletons from elite Hungarian conqueror graves dating to the 10th century carried the Tat C allele, which meant that they belonged to Y-haplogroup N (see here).

We've since had to wait over a decade to get a more comprehensive look at the Y-chromosome haplogroups of medieval Hungarians. The most useful effort to date, a manuscript courtesy of Neparáczki et al., was posted this week at bioRxiv (see here).

The results in the preprint suggest a much more complex picture than simply a migration of an obviously Uralic-speaking population rich in Y-haplogroup N into the medieval Carpathian Basin. But they do confirm the presence of N in Hungarian conqueror elites, and, in fact, of very specific subclades of N that link them to the present-day speakers of Uralic languages from around the Ural Mountains. Here are some pertinent quotes from the prepint:

Three Conqueror samples belonged to Hg N1a1a1a1a2-Z1936, the Finno-Permic N1a branch, being most frequent among northeastern European Saami, Finns, Karelians, as well as Komis, Volga Tatars and Bashkirs of the Volga-Ural region. Nevertheless this Hg is also present with lower frequency among Karanogays, Siberian Nenets, Khantys, Mansis, Dolgans, Nganasans, and Siberian Tatars 23.

...

It is generally accepted that the Hungarian language was brought to the Carpathian Basin by the Conquerors. Uralic speaking populations are characterized by a high frequency of Y-Hg N, which have often been interpreted as a genetic signal of shared ancestry. Indeed, recently a distinct shared ancestry component of likely Siberian origin was identified at the genomic level in these populations, modern Hungarians being a puzzling exception 36. The Conqueror elite had a significant proportion of N Hgs, 7% of them carrying N1a1a1a1a4-M2118 and 10% N1a1a1a1a2-Z1936, both of which are present in Ugric speaking Khantys and Mansis 23.

...

Population genetic data rather position the Conqueror elite among Turkic groups, Bashkirs and Volga Tatars, in agreement with contemporary historical accounts which denominated the Conquerors as “Turks” 38. This does not exclude the possibility that the Hungarian language could also have been present in the obviously very heterogeneous, probably multiethnic Conqueror tribal alliance.

Indeed, a large proportion of the 44 males from elite Hun, Avar and Hungarian Conqueror burials analyzed in the study belonged to Y-haplogroups that can't be plausibly associated with the earliest Uralic speakers, but rather with those of various Indo-European languages, such as I1 and R1b-U106 (these are Germanic-specific markers), I2a-L621 and R1a-CTS1211 (obviously Slavic) and R1a-Z2124 (largely Eastern Iranian).

If most of these results aren't due to contamination, then it's likely that both the early Hungarian commoners and elites were, by and large, derived from Indo-European-speaking populations. No wonder then, that present-day Hungarians are basically indistinguishable genetically from their Indo-European-speaking neighbors and, like them, show hardly any Y-haplogroup N.

See also...

Hungarian Conquerors were rich in Y-haplogroup N (Fóthi et al. 2020)

More on the association between Uralic expansions and Y-haplogroup N

Ancient DNA confirms the link between Y-haplogroup N and Uralic expansions