A tantalizing link

A new paper at PLoS ONE reports on the first human genomes reliably associated with the Single Grave culture (SGC). They were sequenced from remains in a burial at Gjerrild, Denmark, roughly dating to 2,500 BCE.

Surprisingly, one of the male genomes belongs to Y-haplogroup R1b-V1636, which is an exceedingly rare marker both in ancient and present-day populations.

However, the results do make sense, because the earliest instances of R1b-V1636 are in three Eneolithic males from burial sites on the Pontic-Caspian (PC) steppe in Eastern Europe, which is precisely where one would expect to find the paternal ancestors of the SGC population. The SGC, of course, is the westernmost variant of the Corded Ware culture (CWC), and there's very little doubt nowadays that the CWC had its roots on the PC steppe.

A Copper Age individual from Arslantepe in central Anatolia also belongs to R1b-V1636, which suggests that Northern Europe shared a very specific link with Anatolia via Eastern Europe during a period generally regarded to have been the time of early Indo-European dispersals.

Numerous SGC barrows or kurgans dot the landscape in what are now the Netherlands, northwestern Germany and Denmark. Unfortunately, most SGC human remains have been eaten up by the acidic soils that exist in this area.

Citation: Egfjord AF-H, Margaryan A, Fischer A, Sjögren K-G, Price TD, Johannsen NN, et al. (2021) Genomic Steppe ancestry in skeletons from the Neolithic Single Grave Culture in Denmark. PLoS ONE 16(1): e0244872. https://doi.org/10.1371/journal.pone.0244872

See also...

Maykop ancestry in Copper Age Arslantepe

Looking forward to a post-Covid world

I was hoping that the Covid-19 pandemic wouldn't have an immediate impact on the publication of ancient DNA papers and new data, but considering how much things have slowed down in this respect, it seems that I was fooling myself.

So let's take a break until early next year, and then see what happens.

Trust me, we've got a lot to look forward to in the post-Covid-19 world. Based on what I've heard from various sources, here are some predictions about what we might see:

- the search for the Proto-Indo-European homeland will shift west to the North Pontic steppe

- on the other hand, the search for the Proto-Uralic homeland will move deep into Siberia

- the key role of the Single Grave (westernmost Corded Ware) culture in the population history of Western Europe will finally get some attention

- following on from the above, Y-haplogroup R1b-L51 will be revealed as a Single Grave marker

- the idea that the Pontic-Caspian steppe was colonized by migrants from Mesopotamia during the Bronze Age will be forgotten, and, ironically, we'll instead learn that there was a significant influx of steppe ancestry into ancient Mesopotamia

- Old Kingdom Egyptians will come out less Sub-Saharan African than present-day Egyptians.

I probably shouldn't blab everything out, so that's all you're getting from me for now. You'll just have to wait for the rest until next year, or perhaps even the year after that.

See also...

The Balkan connection

The hot topic at the moment is social inequality in Bronze Age Europe, thanks to a new paper by Mittnik et al. at Science. The full article is sitting behind an exceedingly robust paywall here.

However, the genotype dataset from the paper is freely available at the Max Planck Society's Edmond data repository here. Below is my Principal Component Analysis (PCA) of ancient West Eurasian genetic variation featuring 41 of the highest quality ancients from the new dataset. Almost all of them are from the Lech Valley in the Bavarian Alps, covering the period from the Bell Beaker culture (BBC) to the Middle Bronze Age (MBA). Two of the samples are from a mass Corded Ware culture (CWC) burial in the more northerly Tauber Valley.

I've also highlighted other ancients on the plot associated with the BBC and CWC from present-day Netherlands and Germany, respectively. The relevant PCA datasheet can be downloaded here.

Social stratification in ancient Europe is a fascinating topic, and it's an issue that I've started looking at myself (see here). However, I can't see any correlation between the inferred social standing of the individuals from the Lech and Tauber valleys and their positions in my PCA.

Nevertheless, the PCA is interesting in that it highlights considerable genetic heterogeneity within the Lech Valley BBC population. Indeed, how is this heterogeneity even possible, if, as per Mittnik et al., ancient DNA "has shown that the spread of the BBC throughout continental Europe did not involve large-scale migrations"?

Below is another version of my PCA, but this time focusing on three males: Lech Valley Beakers UNTA58_68Sk1 and WEHR_1192SkA, as well as ALT_4 from the aforementioned mass CWC grave in the Tauber Valley. Note that UNTA58_68Sk1 and WEHR_1192SkA represent genetically the most southern and northern, respectively, Lech Valley BBC samples that had enough data to be run in my analysis. I chose to focus on males because they carry the Y-chromosome, which can be informative about male-mediated ancient population expansions.

The PCA outcomes for these individuals are generally in line with their results in other types of genetic analyses, including those based on formal statistics. For instance, compared to the other two, ALT_4 harbors excess early steppe herder ancestry, UNTA58_68Sk1 excess early European farmer ancestry, and WEHR_1192SkA excess European hunter-gatherer ancestry. Moreover...

- UNTA58_68Sk1 shows a non-local isotopic signature and belongs to Y-haplogroup G2a, a marker essentially missing from BBC populations north of the Alps, and is best modeled as a two-way mixture between Bronze Age populations from the Balkans and the Pontic-Caspian steppe (see here), which probably means that he was a migrant to the Lech Valley from south of the Alps

- importantly, UNTA58_68Sk1 is not an isolated case, at least in the sense that several other BBC individuals from Bavaria, Bohemia, Hungary and Poland show varying ratios of Balkan-related ancestry, although almost all of these people are women

- WEHR_1192SkA is very similar to Bell Beakers from the northern Netherlands with whom he shares the R1b-P312 Y-haplogroup, suggesting that he was part of a population that moved into the Lech Valley from potentially as far away as the North Sea coast

- although ALT_4 probably shares the R1b-L51 Y-haplogroup with WEHR_1192SkA and many other BBC and Bronze Age individuals from the Bavarian Alps and surrounds, this can't be used as evidence of significant local genetic continuity after the CWC period, especially considering the comparatively eastern genome-wide structure of ALT_4.

Of course, archeological data suggest that the BBC was influenced in some important ways by the Copper and Bronze Age cultures of the Balkans and Carpathian Basin. So much so, in fact, that Marija Gimbutas, author of The Civilization of the Goddess, believed that the BBC originated in the Balkans from a synthesis of the local Vucedol culture and the intrusive Yamnaya culture from the Pontic-Caspian steppe.

Considering the ancient DNA evidence, however, the main demographic center of the early BBC could not have been south of the Alps.

Rather, it appears that early BBC and even CWC groups from north of the Alps moved into the Balkans and Carpathian Basin, where they may have established contacts with the local elites. If so, this might explain the significant southern cultural influences on the BBC, but limited accompanying genetic impact. This scenario also has support from archeological data (for instance, see here).

See also...

Is Yamnaya overrated?

The Boscombe Bowmen

Single Grave > Bell Beakers

Isotopes vs ancient DNA in prehistoric Scandinavia

Four of the samples from the recent Frei et al. paper on human mobility in prehistoric southern Scandinavia are in my Global25 datasheets. Their genomes were published along with Allentoft et al. back in 2015. So I thought it might be interesting to check whether their strontium isotope ratios correlated with their genomic profiles.

In the Principal Component Analysis (PCA) below, RISE61 is a subtle outlier along the horizontal axis compared to the other three Nordic ancients, as well as a Danish individual representative of the present-day Danish gene pool. Also note that RISE61 shows the most unusual strontium isotope ratio (0.712588). The PCA was run with an online tool freely available here.

To help drive the point home, here's a figure from Frei et al., edited by me to show the positions of RISE47, RISE61 and RISE71. If RISE276 was also in this graph, he'd be sitting well under the "local" baseline, in roughly the same spot along the vertical axis as RISE47.

Interestingly, RISE61 belongs to Y-chromosome haplogroup R1a-M417, while RISE47 and RISE276, who appear to have been locals, both belong to R1b-M269. My guess is that RISE61 was a recent migrant from a more northerly part of Scandinavia dominated by the Battle-Axe culture (BAC). The BAC population was probably rich in R1a-M417 because it moved into Scandinavia from the Pontic-Caspian steppe via the East Baltic. This is what Frei et al. say about RISE61 and his burial site:

The double passage grave of Kyndeløse (Fig 1, S1 File) located on the island of Zealand yielded 70 individuals as well as a large number of grave goods, including flint artefacts, ceramics, and tooth and amber beads. We conducted strontium isotope analyses of seven individuals from Kyndeløse encompassing a period of c. 1000 years, indicating the prolonged use of this passage grave. The oldest of the seven individuals is a female (RISE 65) from whom we measured a “local” strontium isotope signature ( 87 Sr/ 86 Sr = 0.7099). Similar values were measured in five other individuals, including adult males and females. Only a single individual from Kyndeløse, an adult male (RISE 61) yielded a somewhat different strontium isotope signature of 87 Sr/ 86 Sr = 0.7126 which seems to indicate a non-local provenance. The skull of this male individual revealed healed porosities in the eye orbits, cribra orbitalia, a condition which is possibly linked to a vitamin deficiency during childhood, such as iron deficiency.

By the way, RISE47 was buried in a flat grave, which suggests that he was a commoner. RISE276 was found in a peat bog in Trundholm, where the famous Trundholm sun chariot was discovered (see here). He may have been a human sacrifice.

Citation...

Frei KM, Bergerbrant S, Sjögren K-G, Jørkov ML, Lynnerup N, Harvig L, et al. (2019) Mapping human mobility during the third and second millennia BC in present-day Denmark. PLoS ONE 14(8): e0219850. https://doi.org/10.1371/journal.pone.0219850

See also...

Commoner or elite?

Who were the people of the Nordic Bronze Age?

They came, they saw, and they mixed

Not Bell Beaker, not Corded Ware, but...the SGBR complex

I'd be very grateful if someone could explain to me what this new paper at the Proceedings of the Prehistoric Society journal was actually about.

Citation...

Furholt, Martin, Re-integrating Archaeology: A Contribution to aDNA Studies and the Migration Discourse on the 3rd Millennium BC in Europe, Proceedings of the Prehistoric Society, Published online: 10 June 2019, DOI: https://doi.org/10.1017/ppr.2019.4

See also...

Who were the people of the Nordic Bronze Age?

Ancient DNA has revealed that large scale migrations and population replacements have often accompanied major cultural changes in prehistoric Europe. But, for now, my opinion is that the formation of the archeologically ostentatious Nordic Bronze Age wasn't associated with any significant foreign gene flow into Scandinavia. I've tested this as best as I could with the few relevant ancient samples that are currently available.

For instance, below are among the most successful qpAdm mixture models that I was able find for various ancient Scandinavian groups dating back to the local Middle Neolithic (MN) period. The Nordic Bronze Age population is represented by three individuals labeled Nordic_BA. Unfortunately, the guy pictured above, from the famous Borum Eshøj barrow burial in what is now Denmark, didn't make the cut. For more details about my sampling and labeling strategies refer to the text file here.

Nordic_MN_B
CWC_CZE 0.822±0.059
POL_Globular_Amphora 0.178±0.059
chisq 14.478
tail prob 0.341086
Full output

SWE_Battle_Axe
CWC_Baltic_early 0.662±0.028
POL_Globular_Amphora 0.338±0.028
chisq 11.234
tail prob 0.591189
Full output

Nordic_LN
Nordic_MN_B 0.928±0.069
SWE_TRB 0.072±0.069
chisq 12.139
tail prob 0.516307
Full output

Nordic_BA
Nordic_LN 0.851±0.061
SWE_TRB 0.149±0.061
chisq 10.897
tail prob 0.619475
Full output

It's impossible to successfully model the ancestries of Nordic_MN_B and SWE_Battle_Axe simply with the populations that were living in Scandinavia before them. Therefore, it's likely that they were migrants or the recent descendants of migrants to Scandinavia. But there's nothing surprising about that, because they're archeologically associated with the Corded Ware culture (CWC), which has always been seen as intrusive to Scandinavia from the south and east.

Conversely, it's easy to produce statistically sound mixture models for both Nordic_LN and Nordic_BA exclusively with earlier Scandinavian populations. Indeed, based on the outgroups or right pops that I'm using, Nordic_LN is almost indistinguishable from Nordic_MN_B, and the same can be said of Nordic_BA in regards to Nordic_LN.

Of course, if I mixed and matched reference populations from across prehistoric Europe, I could probably come up with some spectacular statistical fits even without the need for any Scandinavians. Essentially that's because Nordic_LN and Nordic_BA are closely related to many earlier and contemporaneous peoples living all the way from the Atlantic facade to the Ural Mountains. My point, however, is that this isn't crucial, despite the dearth of ancient samples from Scandinavia.

This is how things look in a Principal Component Analysis (PCA) of Northern European genetic variation based on my Global25 data. Strikingly, Nordic_MN_B, SWE_Battle_Axe, Nordic_LN and Nordic_BA more or less recapitulate the cluster made up of present-day Swedish samples. The relevant datasheet is available here.

Granted, two of the Nordic_BA samples sit just south of the Swedes, no doubt due to their slightly higher ratios of Neolithic farmer (SWE_TRB-related) ancestry, but this is also an area of the plot that many present-day Danes call home (not shown, because I don't have any suitable academic Danish samples to run).

I'll eat my hat if it turns out that Scandinavia experienced a major population shift (say, more than a collateral ~10%) during the LN and/or BA periods. And I'll post a clip of it online too.

Update 27/08/2019: Four of the samples from the recent Frei et al. paper on human mobility in prehistoric southern Scandinavia are in my Global25 datasheets. So I thought it might be interesting to check whether their strontium isotope ratios correlated with their genomic profiles.

In the Principal Component Analysis (PCA) below, RISE61 is a subtle outlier along the horizontal axis compared to the other three Nordic ancients, as well as a Danish individual representative of the present-day Danish gene pool. Also note that RISE61 shows the most unusual strontium isotope ratio (0.712588). The PCA was run with an online tool freely available here.

To help drive the point home, here's a figure from Frei et al., edited by me to show the positions of RISE47, RISE61 and RISE71. If RISE276 was also in this graph, he'd be sitting well under the "local" baseline, in roughly the same spot along the vertical axis as RISE47.

Interestingly, RISE61 belongs to Y-chromosome haplogroup R1a-M417, while RISE47 and RISE276, who appear to have been locals, both belong to R1b-M269. My guess is that RISE61 was a recent migrant from a more northerly part of Scandinavia dominated by the Battle-Axe culture (BAC). The BAC population was probably rich in R1a-M417 because it moved into Scandinavia from the Pontic-Caspian steppe via the East Baltic. This is what Frei et al. say about RISE61 and his burial site:

The double passage grave of Kyndeløse (Fig 1, S1 File) located on the island of Zealand yielded 70 individuals as well as a large number of grave goods, including flint artefacts, ceramics, and tooth and amber beads. We conducted strontium isotope analyses of seven individuals from Kyndeløse encompassing a period of c. 1000 years, indicating the prolonged use of this passage grave. The oldest of the seven individuals is a female (RISE 65) from whom we measured a “local” strontium isotope signature ( 87 Sr/ 86 Sr = 0.7099). Similar values were measured in five other individuals, including adult males and females. Only a single individual from Kyndeløse, an adult male (RISE 61) yielded a somewhat different strontium isotope signature of 87 Sr/ 86 Sr = 0.7126 which seems to indicate a non-local provenance. The skull of this male individual revealed healed porosities in the eye orbits, cribra orbitalia, a condition which is possibly linked to a vitamin deficiency during childhood, such as iron deficiency.

By the way, RISE47 was buried in a flat grave, which suggests that he was a commoner. RISE276 was found in a peat bog in Trundholm, where the famous Trundholm sun chariot was discovered (see here). He may have been a human sacrifice.

Citation...

Frei KM, Bergerbrant S, Sjögren K-G, Jørkov ML, Lynnerup N, Harvig L, et al. (2019) Mapping human mobility during the third and second millennia BC in present-day Denmark. PLoS ONE 14(8): e0219850. https://doi.org/10.1371/journal.pone.0219850

See also...

They came, they saw, and they mixed

Children of the Divine Twins

The mystery of the Sintashta people

A Bell Beaker superhighway

Below is a density heat map of Bell Beaker pottery finds from a recent paper titled Der Glockenbecher in Europa - eine Karteirung (The mapping of the Bell Beaker in Europe). It's freely available as part of a series of new archeological papers on the Bell Beaker phenomenon at the Journal of Neolithic Archeology (see here).

Particularly eye catching, at least for me, is the trail of high density clusters that runs from the Carpathian Basin to the North Sea, especially in the context of recent online discussions about the potential geographic origins of the non-Iberian, or Yamnaya-related, Beakers with significant steppe ancestry. I'm guessing that this was something of a Beaker superhighway back in the day.

By itself, the heat map is probably very favorable to the rather popular idea nowadays that the Yamnaya-related Beakers originated in the Carpathian Basin. Their ancestors, for instance, may have been Yamnaya groups that arrived from the Pontic-Caspian steppe via the Balkans, and their ethnogenesis may have been sparked by the cultural impulses that were streaming into the region from across Europe, perhaps from as far away as Iberia. The descendants of these early, potentially Yamnaya-derived, Beakers may then have moved en masse to the North Sea region and beyond via the aforementioned superhighway.

However, fortunately, we now also have quite a bit of ancient DNA data to throw into such debates. Note that I added the following labels to the map: Beaker The Netherlands, Beaker Mittelelbe-Saale, Beaker Bohemia, and Beaker Hungary. These are the currently sampled Beaker populations from along the so called superhighway, and you can see how they cluster compared to each other in my Principal Component Analysis (PCA) of ancient West Eurasian genetic variation.

Clearly, what we're dealing with here is not just a series of well settled sites, or a heavily populated trade route, but also a busy migration trail, because of the significant overlap in the PCA between almost all of the Beaker populations.

Interestingly, though, most of the gene flow appears to have gone from the northwest to the southeast, because the Dutch Beakers hardly overlap with the other groups, and arguably form the tightest cluster, suggesting that they're the most genetically homogeneous and unadmixed of these Beakers. Indeed, they're also genetically very similar to the earlier nearby Corded Ware groups from Germany and Scandinavia, so it's unlikely that they derive from recent migrants to Northern Europe. On the other hand, the Hungarian Beakers from the Carpathian Basin are by far the most dispersed of the lot, which certainly means that they're the least genetically homogeneous and probably the most admixed.

Note also that some of them do clearly "pull" towards the Dutch Beakers, suggesting that they might harbor significant ancestry from as far north as the shores of the North Sea.

See also...

The Boscombe Bowmen

Single Grave > Bell Beakers

Dutch Beakers: like no other Beakers

The Boscombe Bowmen

I'm thinking that the Boscombe Bowmen site in Wiltshire, southern England, might be a valuable case study of how the Bell Beaker population, and thus also the present-day western European gene pool, came to be.

Dated to 2500–2140 BCE, this isn't an especially early Bell Beaker grave, but its inventory is intriguing. It includes seven All-Over-Cord (AOC) beakers and one Cord-Zoned-Maritime (CZM) beaker.

Maritime beakers are quintessential Bell Beaker gear, and they're named as such because most of them have been recovered from sites along the Atlantic and Mediterranean coasts. However, strictly speaking, AOC beakers aren't Bell Beaker artifacts. Rather, their origin is said to be in the Single Grave culture, which is, of course, the northwestern European variant of the Corded Ware culture.

Genotype data for two samples from the Boscombe cemetery were analyzed in and published along with last year's Olalde et al. Beaker paper. In tune with the archeological data, one of these individuals came out very Corded Ware-like, with a lot of steppe ancestry, and the other rather southern, with among the lowest level of steppe ancestry for a Beaker dated to later than ~2500 BCE.

To take a closer look at their genetic affinities, I put together the graph below based on a couple of D-stats of the form D(Mbuti,X)(Yamnaya_Samara)/D(Mbuti,X)(Barcin_N,WHG). The bowmen are labeled I2416 and I2417, and the relevant datasheet is available here.

Considering these results, I2416 and I2417 may have been migrants, or the descendants of migrants, from such relatively far flung places as, say, what are now northern Germany and western France, respectively. [Edit: as per the comments below, these individuals are probably third-degree relatives, which makes it unlikely that they're migrants to the region, although it's still possible that their recent ancestors may have been migrants]

Note also that almost all of the populations are basically sitting between the two bowmen. This indeed suggests to me that the cultural processes and resulting population mixtures that took place at the Boscombe site also played out across the width and breadth of the Beaker realm, giving rise to heterogeneous Beaker groups almost everywhere within it and, eventually, the present-day western European gene pool.

Most of the Scandinavians, as well as the closely related British Anglo-Saxons, are slightly pulled above the red trend line by their excess genetic affinity to Western European Hunter-Gatherers (WHG). This phenomenon appears to date back to at least 2275-2032 BCE, because Nordic_LN:RISE98 is clearly affected by it and dated to this period.

My guess is that Single Grave populations from what is now Denmark and surrounds harbored much higher levels of WHG-related ancestry than the more easterly Corded Ware (aka Battle-Axe) Scandinavian groups, and they passed this onto present-day Scandinavians. Nordic_LN:RISE98, although from a burial site in what is now southern Sweden, might well be of Danish Single Grave origin.

See also...

Single Grave > Bell Beakers

Dutch Beakers: like no other Beakers

Hungarian Yamnaya > Bell Beakers?

Dutch Beakers: like no other Beakers

In my last two blog posts I tried to explain why the so called Bell Beakers of prehistoric Europe cannot be confidently derived in any significant way from the Yamnaya population of the Carpathian Basin, and are more likely to have been an offshoot, in varying degrees, of the Single Grave or Corded Ware people of the Lower Rhine region (see here and here).

To help drive my message home, below is a series of new Principal Component Analysis (PCA) plots that illustrate the unique position of Dutch Beakers from the Lower Rhine relative to the Corded Ware population of Germany and all the other Beaker groups sampled to date. The relevant datasheet is available here.

The Dutch Beakers don't exactly sit between the Corded Ware and the other Beaker samples, but generally at the apex of their clusters, suggesting to me that they're not a mixture between Corded Ware and one or more of the other Beaker groups, but rather, as per my recent argumentation, a genetically homogeneous, relatively unique and thus long-standing Corded Ware-related population that may have contributed significant gene flow to the other Beaker groups.

Please note also that all of these outcomes can be confirmed with various types of formal statistics. I know this because I've done it.

See also...

Late PIE ground zero now obvious; location of PIE homeland still uncertain, but...

Single Grave > Bell Beakers

I've been studying in detail the genetic substructures within the Bell Beaker population with formal statistics and Principal Component Analyses (PCA). As far as I can see, among the two most homogeneous, and thus least likely to be recently admixed, Beaker groups are the Dutch Beakers and also the Dutch and British Beaker males belonging to Y-haplogroup R1b-P312. This, of course, makes good sense, because both the Dutch and British Beakers are so called Rhenish Beakers.

The results are also in line with the observation that the Dutch Beakers are the quintessential Beakers in terms of physique, with three quarters or more sporting exceedingly brachycephalic, planoccipital skulls (like this).

Moreover, these two Beaker groups are among the most Yamnaya-like Beakers, with almost as much Yamnaya-related ancestry as the Corded Ware culture samples from Germany (~60% vs ~70%). As a result, in my PCA of ancient West Eurasian genetic variation the Dutch Beakers form a more or less continuous, west to east cline with these and other Corded Ware individuals that runs all the way to the Yamnaya cluster.

In the same PCA, the R1b-P312 Dutch and British Beaker males form a tight cluster at the apex of a Beaker cline that stretches to European Neolithic groups with no steppe ancestry. The only Beaker who is positioned clearly east of the Dutch/British R1b-P312 Beaker cluster is from Hungary, and in all likelihood he harbors recent Yamnaya ancestry because his Y-haplogroup is the Yamnaya-specific R1b-Z2103.

These findings potentially have important implications for the origins of the Dutch Beakers and the Beakers who dominated much of Central and Western Europe during the Late Neolithic and Bronze Age, and these are:

- the Dutch Beakers are unlikely to be the result of a recent migration from afar into what is now The Netherlands and surrounds, but rather the descendants, by and large, of the earlier local Single Grave (and thus Corded Ware) populations

- the R1b-P312 lineages in the Dutch and British Beakers probably derive from Single Grave R1b-P312, which suggests that R1b-P312 was common among some clans within the Corded Ware culture

- the spread of most of the Yamnaya-related or steppe ancestry and quintessential Beaker physique across the Beaker world and into Western Europe can probably be blamed on the massive expansions of Beakers from what is now The Netherlands and surrounds (ie. the Lower Rhine region)

- late Yamnaya groups contributed some ancestry to eastern Beaker groups, such as those in the Carpathian Basin, but the Dutch Beakers acquired their high level of Yamnaya-related ancestry from their Single Grave predecessors, who, in turn, acquired it from their proto-Corded Ware ancestors from the steppe.

Admittedly, I find the discussion about the origin of the Bell Beaker cultural package somewhat confusing. For all I know, it might have come from Iberia, the Carpathian Basin, or even North Africa. But this post isn't about that, it's about the homeland of the classic Beaker warrior male, with his R1b-P312, Corded Ware-like genome-wide genetic structure and brachycephalic skull. I'm almost certain now that this was the Lower Rhine region.

See also...

Hungarian Yamnaya > Bell Beakers?

Dutch Beakers: like no other Beakers

Late PIE ground zero now obvious; location of PIE homeland still uncertain, but...

Hungarian Yamnaya > Bell Beakers?

Ever since the publication of the Olalde et al. Beaker paper (see here), there's been a lot of talk online about Hungarian Yamnaya as the most likely source of the Yamnaya-related, R1b-P312-rich northern Bell Beakers who went on to dominate much of Central and Western Europe during the Late Neolithic and Bronze Age.

Certainly, this is still possible, and we might find out soon if it's true because several Hungarian Yamnaya samples are apparently about to be published. But I wouldn't bet the proverbial farm on it just yet.

The most Yamnaya-like Beaker in the Olalde et al. dataset and ancient DNA record to date is from the Szigetszentmiklós burial site, which is indeed in present-day Hungary. But this individual, labeled I2787, is dated to just 2457–2201 calBCE, which isn't an early date for a Beaker and probably a couple hundred years past the proto-Beaker time frame.

Moreover, he belongs to Y-haplogroup R1b-Z2103, a paternal marker most closely associated in the ancient DNA record with eastern Yamnaya groups. And he doesn't exactly look like a classic northern Beaker, because he doesn't have a brachycephalic head with an exceedingly flat occiput (like this).

So I'd say that this is either an acculturated Beaker of recent Yamnaya origin, or perhaps the son of a Yamnaya father and Beaker mother. Below are several qpAdm mixture models that I ran to explore the latter possibility. They look very solid.

Beaker_Hungary_I2787
Beaker_Bavaria 0.442±0.045
Yamnaya_Samara 0.558±0.045
chisq 8.562
tail prob 0.73982
Full output

Beaker_Hungary_I2787
Beaker_Czech 0.441±0.045
Yamnaya_Samara 0.559±0.045
chisq 10.009
tail prob 0.61513
Full output

Beaker_Hungary_I2787
Beaker_The_Netherlands 0.576±0.062
Yamnaya_Samara 0.424±0.062
chisq 11.469
tail prob 0.489238
Full output

The idea that I2787 is a Beaker with recent Yamnaya ancestry isn't an original one. It was put forth very eloquently and convincingly months ago by the Bell Beaker Blogger himself:

Szigetszentmiklós Cemetery (Santa's Six Foot Elves)

I2786 is another Beaker male from the Szigetszentmiklós site who shows excess Yamnaya-related ancestry compared to most other Beakers. Again, it's likely that this individual harbors recent Yamnaya ancestry, because his Y-haplogroup is I2a-M223, which has been recorded in eastern Yamnaya alongside R1b-Z2103.

So my gut feeling for now is that Hungarian Yamnaya samples will mostly belong to Y-haplogroups R1b-Z2103 and I2a-M223, rather than R1b-P312, and thus they won't fit the bill in any obvious way as the population that may have given rise to northern Beakers.

One of the oldest individuals in the ancient DNA record belonging to R1b-P312 is I5748, a Beaker dated to 2579–2233 calBCE from the Oostwoud-Tuithoorn burial site in what is now West Frisia, The Netherlands.

Interestingly, this part of Northwestern Europe was home to the Single Grave population shortly before I5748 was alive. And the Single Grave culture is a variant of the Corded Ware culture. So can anyone tell me if there's any evidence that I5748 and his kind were relative newcomers to West Frisia, from, say, somewhere in the direction of the Carpathian Basin? If not, then what are the chances that northern Beakers are by and large the descendants of the Single Grave people?

In fact, there's not much difference in terms of genome-wide genetic structure between the Beakers from the Oostwoud-Tuithoorn site and Corded Ware people from what is now Germany. The Principal Component Analysis (PCA) below illustrates this well. But, you might say, Corded Ware males by and large belong to Y-haplogroup R1a-M417. Yep, but this doesn't mean that R1b-P312 wasn't common in some Single Grave clans.

At this stage, I don't have a clue where the northern Beakers might have come from, and unfortunately I don't have any inside information about the Y-haplogroups of Hungarian Yamnaya. I don't even know if any Single Grave samples are being analyzed. But I'll leave you with this map from a recent paper by French archeologist and Beaker expert Olivier Lemercier (see here). To me it suggests rather strongly that northern Beakers developed from the synthesis of Corded Ware newcomers to Western Europe and indigenous Western Europeans. As far as I can tell, that's what the paper basically argues as well.

See also...

Single Grave > Bell Beakers

Dutch Beakers: like no other Beakers

Late PIE ground zero now obvious; location of PIE homeland still uncertain, but...