If you’ve been reading this weblog this headline in Science won’t be surprising, Three-part ancestry for Europeans. The writer, Anne Gibbons, draws up stuff which has been out for a long time (e.g., Ancient human genomes suggest three ancestral populations for present-day Europeans). But she also has taken the temperature of researchers in terms of where the results are going, as obviously there are hunches and inferences the scientists are making which are not publication worthy, yet. From the article:
How do you make a modern European? For years, the favored recipe was this: Start with DNA from a hunter-gatherer whose ancestors lived in Europe 45,000 years ago, then add genes from an early farmer who migrated to the continent about 9000 years ago. An extensive study of ancient DNA now points to a third ingredient for most Europeans: blood from an Asian nomad who blew into central Europe perhaps only about 4000 or 5000 years ago. This third major lineage originated somewhere in northwestern Asia, perhaps on the steppes of western Asia or in Eastern Europe.
Previous studies have also found some genetic ties between Europeans and Native Americans, notes population geneticist Wolfgang Haak of the University of Adelaide in Australia, a co-author on the new study, a draft of which is available on a biology preprint server. Thanks to these ancient Eurasians, “someone with northern European ancestry is more closely related to Native Americans than southern Europeans are,” says Pontus Skoglund, a postdoc at Harvard who analyzed DNA from the Swedish skeletons but was not a co-author.
In their talks, Haak and Krause each proposed that the late influx of these “ghost” Eurasians might be related to what’s known archaeologically as the Corded Ware culture of nomadic herders, who imprinted twisted cord or rope onto their pottery. These nomadic pastoralists herded their cattle east from the steppes north of the Black Sea and occupied large areas of northeast and central Europe by 2500 B.C.E.
So now we have a name, the Corded Ware. This is not archaeologically entirely surprising, though what little I know has been gleaned from Wikipedia. Those more versed in this domain can now offer their own interpretations of the implications, but I’m rather sure that the geneticists are confident about their results if they’re floating it about, and have probably cross-checked with some archaeologists. I do think though that we know have a sense of why R1a is so frequent across much of Europe. It doesn’t show up in the ancient DNA, but probably came with Corded Ware.