Cups runneth over: Beaker folk account for most of the British genome
Genetic analysis finds migration starting at 2500 BCE changed the ancient Britons almost completely. Paul Biegler reports.
A hard Brexit might sever long-standing British ties with Europe, but new research published in the journal Nature shows the island nation has links to the Continent that won’t be unwound with a mere stroke of the politician’s pen.
A team led by David Reich, a geneticist at the Harvard Medical School in the US, has found the genetic make-up of early Britons underwent a near complete renewal in the space of just a few hundred years following 2500 BCE. That demographic upheaval, the authors write, resulted from a wave of continental migration that ultimately contributed to the paler skin and eyes we now associate with the average Brit.
To reach their dramatic findings the researchers followed the fortunes of the humble beaker, although one rather different from the handled variety that often carries the iconic British cuppa.
The Bell Beaker was a curved ceramic vessel, probably for drinking, that is something of an anthropological ID tag, grouped as it often was in a set of funerary objects – called “the Beaker complex” – that also contained copper daggers, stone wrist guards and buttons with unusual perforations.
In the period before the arrival of the Bronze Age in 2500 BCE, the Bell Beaker got around, spreading from the lower Rhine to Italy, the Atlantic coast of France, northwest Africa and thence to Britain and Ireland.
Its mode of transport, however, has been intensely debated. Was it an article of trade, sweeping across lands as a sought-after piece of exotica, or was it brought by migrants, a part of the cultural signature of the “Beaker folk”?
To find out, Reich’s team applied a technology called DNA hybridisation to the genomes of over 400 Europeans who lived between 4700 and 800 BCE, 226 of whom were Beaker people, and compared them with around 2500 modern specimens. They found little genetic similarity between the Beaker folk of central Europe and Iberia, suggesting migration wasn’t the cause of that particular Beaker diaspora.
In Britain, however, it was a different story.
The Beaker folk of Blighty had strong genetic similarities with those of central Europe, with both tracing their origins still further East to the Eurasian Steppe, a region straddling the modern day Black and Caspian seas. Those links, the authors conclude, firm human exodus as the cause of beaker dispersal throughout the British Isles.
“[T]he spread of the Beaker complex introduced high levels of steppe-related ancestry and was associated with the replacement of approximately 90% of Britain’s gene pool,” the authors write.
Related research, also led by Reich, investigates the population movements that led to the adoption of farming in Europe.
Agrarian practice began in the seventh millennium BCE, having spread from the so-called Fertile Crescent, an area including much of what are now Israel, Jordan, Syria, Lebanon and Iraq, via Anatolia, which covers most of modern day Turkey.
The researchers sequenced the genomes of 225 ancient skeletal remains from a cluster of regions in south-eastern Europe, including the Balkan peninsula, and analysed them along with genetic data from 777 contemporary humans
For thousands of years after the first arrival of farming, they conclude, south-eastern Europe continued to serve as a west-east “genetic contact zone”, including with people of the steppe, whose genetic legacy was to ultimately suffuse much of the population of northern Europe.
The article also appeared in Nature.