The Beaker phenomenon and genetic transformation of Northwest Europe 2017. A layman's take.

They say that you cannot write prehistory, but here in Britain, prehistory is currently being rewritten, and it's thanks to DNA.  A new study , "The Beaker Phenomenon, And The Genomic Transformation Of Northwest Europe" has been published on BioRxyv.  A new study that recently analysed the DNA of 170 ancient human remains in Europe.

A little background...

1. British Archaeology and the Bell Beaker

British archaeologists have long been aware of a late prehistoric artifact culture found across the British Isles, and across large areas of Western Europe.  It bridged the Late Neolithic and Early Bronze Age periods around 4,400 to 3,800 years ago.  It was characterised by the use of fine bell-shaped beaker pots, usually red ceramic fabric, heavily decorated with simple motifs.  These motifs were characteristically impressed with a fine toothed comb or dentated spatula.  Many Bell beaker burial rituals have been excavated and studied.  The inhumed body would usually be crouched on the side, roughly on a north to south alignment.  A bell beaker would often be stood near to the body, at the feet, or near the head.  Other grave goods often included barbed and tanged flint arrowheads, flint flakes and blades, antler picks, sometimes one or two more beakers, amber beads, copper awls, and gold earrings / hair rings.  64% of British Beaker burials were flat graves, but sometimes a barrow or cist would be erected above it (Beaker Pottery of Great Britain & Ireland. DL Clarke.  CUP 1970).

Above, a flint barbed & tanged arrowhead of the Beaker Culture, that I found and recorded during a surface collection survey some years ago.

Archaeologists studying the artifact culture in Britain, compared the British finds to those on the Continent in order to try to find an origin for these people.  They suggested either Brittany in North West France, or the Lower Rhine Valley, in the Netherlands and Northern Germany.  Some alternatively promoted Iberia as the origin.

Then British Archaeology entered an intellectual phase where it became fashionable to dismiss migration or invasions of people, in favour of cultural exchange.  Pots not People.  Rather like today, we British wear denim, t-shirts, listen to R&B, and drink coke.  However, we have not been displaced by North Americans - we just absorbed the artifacts of another culture.  From the 1970s on, many late prehistoric migrations were dismissed by British archaeologists as cultural exchanges rather than representing population displacement.

2. The New Population Genetics and the Steppe Pastoralists.

A new field of study has been gathering pace with the arrival of the 21st Century, that uses genetic evidence, to explore past migrations, movements, admixtures, and origins of peoples.  The earliest pioneers used blood types, then mitochondrial DNA mutations, followed by STR of Y-DNA.  Some of the early conclusions supported the new orthodoxy of British Archaeology.  Stephen Oppenheimer's infamous publication "The Origins of the British" championed that there had been little change in British populations since the Ice Age.  They were to be proven wrong.  Early conclusions, based on little evidence, misunderstandings that were later corrected with more data, seriously damaged the reputation of population genetics in British prehistoric studies.

The most common Y-DNA haplogroup of Western Europe, particularly of Ireland and Britain was R1b.  Early mistakes gave this male haplogroup an Ice Age origin of the Basque Region in Southwest Europe.  As more data gathered, and debate developed, it became apparent that the origin was not the Basque region, but the Pontic and Caspian Steppes of Eurasia!  It became associated with an archaeological culture in Southern Russia called the Yamna.  The R1b and R1a haplogroups appeared to have spilled off the Steppes into Europe during the Copper Age during a significant migration event around 4,900 - 4,600 years ago.  In Eastern and Central Europe, this migration of pastoralists appears to be responsible for the fused artifact culture known as the Corded Ware (again, after a prehistoric pottery style).

A few lectures on Youtube to watch:

Havard lecture by David Reich 2015.

CARTA lecture by Johannes Krause 2016

That brings us up to date.  In summary, population geneticists have discovered a movement of people, not just pots, from the Steppes into Europe.  Modern Europeans descend from an admixture of three major founder populations: 1) the Western Eurasian hunter-gatherers, then a layer of 2) Early Neolithic farmers (that originated in Anatolia and the Middle East), and finally, 3) the Steppe Pastoralists.  The actual mix varies not only from person to person, but also regionally across Europe.

So how does the Bell Beaker Culture of Britain and Western Europe fit into all of this?  The strong assumption over the past couple of years was that the diffusion of R1b Y-DNA haplogroups occurred then, so therefore, it was a simple extension of this westward drift across Europe that originated on the Pontic and Caspian Steppes.  It first spawned the Corded Ware Culture in Central Europe, but then when it met Western Europe, spawned the Bell Beaker Culture.  However, until now, this hypothesis hadn't been tested.

The Beaker phenomenon and genetic transformation of Northwest Europe 2017

Has now examined some of these questions, through the examination of an unprecedented scale of ancient DNA sampling. The link to their published document (which is still awaiting peer review) is at the top of this post, and I'd invite others to read it for themselves.  An article covering the document can also be read on the Scientific American.  However, I personally with my layman head take five suggestions from the study.

  1. They found that the DNA of human remains on Continental Europe did not suggest one cohesive or homogeneous population.  There was in this case, evidence of cultural diffusion.  Different peoples were taking on the Bell Beaker artifact assemblage in Western Europe.  Pots rather more than people.  This was a great surprise, as we still know from the earlier study, that much of our DNA and Y-DNA in particular, originated around 400 years earlier from the Eurasian Steppes.  However, although the Central European Corded Ware Culture does still appear to have been a response to that great influx of new people from the Steppes, the picture with the Western European Bell Beaker is more complex.
  2. An exception was Britain.  Here, the remains associated with Bell Beaker Culture were all one population, and they were very different to the earlier Neolithic population of Britain.  It appears to have been a case of population displacement.  They suggest at least 90% displacement!  It means that very few or none of our Neolithic ancestors built the amazing monuments of Neolithic Britain.  They were built by earlier peoples, that our ancestors displaced.
  3. They confirm a Lower Rhine origin as most likely for the British Beaker People.  The ancient DNA that most closely matched British Beaker DNA, came from Beaker human remains in the Netherlands and Northern Germany.  This correlates nicely with the 1970 archaeological study mentioned above.
  4. It's confirmed.  Previous to their entry into the British Isles, there is no evidence of any Steppe ancestry, no Steppe autosomal DNA, no Steppe Y haplogroups such as R1b-L21 here.  (Nor any mtDNA haplogroup H6a1).  The Beaker people from the Lower Rhine, brought the initial layers of this DNA to Britain.  The founder population were admixed, but with significant percentages of Steppe ancestry, particularly on Y lines.
  5. The previous Neolithic Farmer population were mainly Y haplogroup I2, and appear to have descended mainly from populations in the South, from Iberia, rather than from the Danube, although before that from Anatolia.  The modern population that is closest to them today are Sardinians.

Also as a layman, I guess that this suggests that most, or even any "Neolithic Farmer" DNA suggested by our ancient ancestry calculators, was most likely picked up elsewhere than Britain, and brought here by later migrants (descended through that mixture of cultural diffusion and admixture), rather than directly from the British Neolithic population.

I also notice a correlation with an Irish study last year ("Neolithic and Bronze Age migration to Ireland and establishment of the insular Atlantic genome" Cassidy etal.  Queens University Belfast 2016), that again, suggested major displacement of earlier peoples in Ireland, at the end of the Neolithic, by a population with largely Steppes origins.

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