Sunday, March 28, 2021

Tales from the Supp. (Booth et al, 2021)

Booth et al, 2021 drill down to a greater time-scale resolution of the genetic turnover in Early Bronze Age Britain (~94%).  Was it a chainsaw massacre or was it a lengthy and complex process?

This paper looks at the 101 C-EBA Olalde samples over time, and adding the archaeological lens, conclude that the Beaker genetic ascendancy was more gradual than sudden, perhaps taking several hundred years.  This means Neolithic genetic enclaves probably persisted to some degree before succumbing to marital annihilation.  (marital not martial - although some married people might claim otherwise)

There's really three major issues this paper looks at with regards to popular interpretation of Britain's transformation.  The initial decrease of the Neolithic stock, which current data shows was rather sudden than an attenuation of Neolithic ancestry over time as the "younger sons hypothesis" would predict.  With that, the lack of a gradual increase in Neolithic ancestry among Beakers for several centuries.  And eventually, a small but significant increase in some sort of Neolithic ancestry which would almost need to be local.  This last point is especially important because it would taken an invasion of people with significant Neolithic ancestry to reverse the shift in a Chalcolithic wipeout scenario.


Barrow at Normanton Down, Wilshire (Historic England)


- They counter the notion of Kristensen and others that demographic change around Europe was mostly effected by bands of exogamous, un-landed warriors (younger sons) who took local wives wherever they went.  (and I will clarify a difference between patrilocality with exogamous female mobility and exogamy based on highly mobile (conquering) males).  And yet, it would seem based on the analysis of British genetic-genealogies from Olalde, British Beakers intermarried a lot less frequently than we might expect, at least initially.

- The selection of remains sampled for testing may have been biased towards crouched inhumations which reflect the dominant burial practice of Beakers.  And that it is possible, if not likely, that cremations (the dominant burial method of the British Neolithic) or burials in more marginal areas were less represented in the EBA genetic landscape, hiding in a sense, the full population demographic.  Booth et al further remark about the resurgence in Neolithic ancestry as testimony to this possibility.  

And while they concede that surging Neolithic ancestry could be coming from France or other places in the continent, essentially confirming a Chalcolithic wipeout scenario, the current genetic analysis may have difficulty distinguishing between Neolithic ancestry native to the Isles and those of France (for example).  (This is a question that might be resolved even without trying to test British cremated remains if, for example, the affinities of MLBA British Neolithic ancestry can be more accurately placed.  

- One of the main problems for British archaeologists with a wipeout scenario has been the fact that Neolithic traditions "appear" to be carried forward in the Beaker Age, suggesting at least some continuity.  The ~94% figure seems rather severe for the degree of influence from less than 10% of a marginalized population.  Whereas the repurposing of monuments may be entirely the work of immigrant Beakers, food vessels are another story.  So the Neolithics may not have been exterminated or genetically flooded in Britain as the numbers initially suggest.  A situation may exist where Neolithics were concentrated into genetic enclaves, such as Southern Ireland or the Irish Sea, to re-emerge if only slightly.

- Although they question the idea of mounted warriors lopping heads off at full gallop, the fact that British Beakers seem so un-shifted for so long in their generations, seems a bit paradoxical.  If the immigration into Britain involved equal numbers of men and women, then that undercuts the need for landscape roasting and booty wives in a younger sons hypothesis.  

If the decrease in Neolithic numbers was more gradual than the numbers suggest, it may be that Beakers immigrated over a span of several hundred years diluting the British Neolithic stock which, as an increasingly mixed population, continued the invisible cremation practice.  Or, it could be the simple and cruel process of elite domination de-landing and marginalizing Neolithics, generation after generation.  And/or, maybe Beakers were more successful in raising large, healthy families.

Here's another possibility (my own), that the Beaker pastoral economy yielded so much more in dreary, rainy, grassy-fields-full-of-rocks, miserable Britain, so much more than molded grain stocks or pulling limp turnips from the ground by people forced onto more marginal and less improved landscapes.  

...but while male mobility is viewed as the result of activities such as warfare and trade, women are figured as passive objects of exchange in exogamous patterns of marriage (Frieman et al. 2019). Women, it is argued, moved as wives, while men moved as significant social agents. The language of nineteenth-century evolutionism is reflected in the image of young male war-bands whose aggressive, competitive actions reflect an innate drive to attain political and economic domination. We can call into question the double standards that pervade this difference in the interpretation of male and female mobility.

I don't know that this should be at odds with itself.  It is demonstrable that Beakers practiced patrilocality with female exogamy when they were settled (see Sjogren et al, 2019), while large numbers of men were definitely not settled throughout Europe.  Beaker settlers heading to Britain probably surveyed prospective territories at least a year or more in advance.  As company-sized units comprised of extended families, they would have been interested in land poorly defended or with weak claims.  Advanced parties of men would begin preparations building livestock cores, houses, wells, fences, etc.  Simply parachuting in to a new territory with women and small children would be suicide without physical security.  There in lies the paradox.  De-landing natives from prime real estate requires violence or the threat of violence. 

In fact, as Booth et al show, the genealogies of early Beakers don't show us a love-fest between the two peoples.  However, their main points are valid in that, while the end genetic result is clear, the true demographic landscape from C-EBA Britain probably has some missing folks.


Abstract

"Large-scale archaeogenetic studies of people from prehistoric Europe tend to be broad in scope and difficult to resolve with local archaeologies. However, accompanying supplementary information often contains useful finer-scale information that is comprehensible without specific genetics expertise. Here, we show how undiscussed details provided in supplementary information of aDNA papers can provide crucial insight into patterns of ancestry change and genetic relatedness in the past by examining details relating to a >90 per cent shift in the genetic ancestry of populations who inhabited Chalcolithic and Early Bronze Age Britain (c. 24501600 BC). While this outcome was certainly influenced by movements of communities carrying novel ancestries into Britain from continental Europe, it was unlikely to have been a simple, rapid process, potentially taking up to 16 generations, during which time there is evidence for the synchronous persistence of groups largely descended from the Neolithic populations. Insofar as genetic relationships can be assumed to have had social meaning, identification of genetic relatives in cemeteries suggests paternal relationships were important, but there is substantial variability in how genetic ties were referenced and little evidence for strict patrilocality or female exogamy."



Tales from the Supplementary Information: Ancestry Change in Chalcolithic–Early Bronze Age Britain Was Gradual with Varied Kinship Organization

TJ Booth, J Brück, S Brace, I Barnes - Cambridge Archaeological Journal
… Similar shifts in ancestry have been iden- tified in other parts of Europe in
the third millen- nium BC around the same time as the Corded Ware and
Bell Beaker phenomena, and they have been interpreted as indicating …

10 comments:

  1. Thanks for sharing this. There needs to be a lot of discussion combining archaeology and ancient DNA to understand Bell Beaker.

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  2. This study asks the wrong question (whether people were Steppe-related or local Neolithic) when they look neither one nor the other.
    The Beaker people were of mixed ancestry, the Neolithic in them mostly coming over to Britain with them. They became more Eastern Baltic/North Central European as they admixed with women sent over by their continental equivalents. They later became more Neolithic again, as they admixed with women sent over by their later, more southerly continental equivalents (from places like the Alps and the Pyrenees).

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  3. Makes a lot of sense to me... Maybe the idea of new money on the hoof and dashing blond men knocking up the village girls amidst pestilence and crop failure belongs more to the R1a explosion of Corded Ware a millennium before. Archeology seems to be pointing at a lot of people engaging in activities not directly related to survival, such as importing deer from Norway in the Hebrides. Driving your pigs all the way to Stonehenge. Giving a splendid burial to a gentleman from the Alps ... It is hard to accept, for me at least, that there can be no record of such times, but there it is. I am, or was, a Beowulf student. All the leeads that I followed led me back to the work of the Irish peregrini, who took great pains to Christianise the heathen holy places. They did not cut down the revered oak trees, but rather redacted the old lore, keeping the fabric, but fundamentally altering the narrative. The statement thus made was to compliment the heathens with their formulation of the naturale bonum, snatching it away from them at the same time. I am talking Siegfried, dragon, but I am also talking Fomori, talking Curoi McDare recast as Cyrus sun of Darius. The genius behind all this was pope Gregory VII, the psychiatrist of sixth century Western Europe.
    Back to 2000 BC. What was of value to people in them days? What language did they speak? What was their lingua franca? If there was a garbled story, it was lost in the telling. Whether the Fomori refer to an ancient dark skinned agricultural predecessor, or to North African slave traders, there is no way of knowing. Or is there? What we have is the fabric. Very ancient! But IA or BA? Not a clue.
    The peregrini have rendered unto us the fabric, but mussed up the narrative, what with their giants from under the sea ... Pathetic efforts to match the then then existing traditions to the story of Genesis.
    Intriguingly, the fabric of an ancient narrative is still there in manuscripts from the 14th century. In itself garbled, as oral traditions are, it is redacted according to principles that are known and documented.

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  4. Perhaps I am wrong above, and British Neolithic DNA did persist? I've just had my aDNA tested. As far as I can tell, my family tree is wholly British, and my greatest number of autosomal matches is with Irish Neolithic. (Although, having said that, matches with Esperstedt Neolithic, Rathlin 1, Karelia MHG and Georgia MHG are similarly high.)

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  5. Yes Nicolas your Ancestors came from the Steppe...

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    Replies
    1. Oddly, there were less matches with German Bell Beaker, Yamnaya and even Anglo-Saxons.
      Spain Neolithic & Chalcolithic had more matches than each of these.

      My British ancestry seems to have been highly mobile, springing from the four corners of ancient Europe. And I wonder whether a resurgence of British Neolithic DNA after Bell Beaker mirrored a resurgence of older British DNA after the Anglo-Saxons?

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    2. @ Nicolas

      Maybe the Bronze Age Collapse had something to do with it ? Maybe some migration from the Isles to the Continent lessened the pressure on the Neolithic related people ?

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    3. @ Nicolas

      Or maybe less metal trade meant less competition for the Alpha position, less roving bands of warriors etc. In other words everyone became equally poor...

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  6. The language of nineteenth-century evolutionism is reflected in the image of young male war-bands whose aggressive, competitive actions reflect an innate drive to attain political and economic domination."


    Yeah, like that's never happened. This thinking drips of 'we're fixing the bias,' which is actually just 'our bias is better than theirs. All over the world, in hundreds of cultures, women have been treated as property. That doesn't mean that we can project into prehistory without doubts, but where and when have we seen women attain political and economic domination?

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  7. Check this out: The Digital Atlas of Innovations - Wheeled Vehicles

    Interactive map showing the spread of wheeled vehicles, starting from centra/eastern Europe:

    https://atlas-innovations.de/de/wheeled-vehicles

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