New study unearths our Scandinavian ancestors
Since the last Ice Age, Scandinavia has experienced two almost total population turnovers. The most recent great migration is still clearly visible in our present-day gene pool. This is shown in a new study published in Nature that a number of archaeologists from the University of Gothenburg participated in.
The study 100 Ancient Genomes Show Repeated Population Turnovers in Neolithic Age Denmark is one of four articles published simultaneously in the journal Nature based on analyses of DNA and dietary markers from 100 tooth and bone remains found in Denmark.
The skeletons originate from a period of 7,300 years, ranging from the Mesolithic, Neolithic, and early Bronze Age. The oldest remains belong to Koelbjerg Man, who was alive about 10,000 years ago.
“Previously it has been assumed that we Scandinavians were descended from hunters and gatherers from the Stone Age, but this assumption has now been completely overturned,” says Kristian Kristiansen, Professor of Archaeology at the University of Gothenburg, who led the study together with Eske Willerslev, Thomas Werge and Morten Allentoft from the University of Copenhagen.
Karl-Göran Sjögren and Bettina Schulz Paulsson, also from the University of Gothenburg, also participated in the study.
“What I have done is model the carbon-14 dating, to obtain a more precise dating of the Neolithic genes. With the carbon-14 modelling, we could, for example, narrow down that time period to around 1,000 years,” says Bettina Schulz Paulsson.
Herders
The analysis of the 100 prehistoric skeletons shows that our genetically closest relatives are in fact the Yamnaya people – a group of herders from the Pontic Steppe, a region that today includes Ukraine, southwest Russia and western Kazakhstan.
These people interbred to some extent with Eastern European peasant groups to form what is termed the Corded Ware complex. Groups of these people then migrated to northern Europe just under 5,000 years ago, during the younger Stone Age, and settled in Sweden, Norway and Denmark (in Denmark they were called the Single Grave culture and in Sweden the Battle Axe culture).
“Genetically, we are still more or less Yamnaya today,” Kristiansen says.
Two population turnovers
Another discovery concerns the changes in the population that have taken place since the last Ice Age in Scandinavia. The researchers have been able to show that a nearly complete population turnover has occurred twice within a period of just a thousand years.
The first occurred about 5,900 years ago, at the beginning of the archaeological era known as the Neolithic, or New Stone Age. When a farming people immigrated to Denmark, the hunter-gatherer and fisher population known as the Ertebølle culture disappeared completely.
The new culture consisted of farmers with genetic roots in the Middle East – in Anatolia, the Asian part of today’s Türkiye – who had to some extent mixed their genes with hunter-gatherers they encountered while travelling across Europe.
It was this culture that introduced agriculture, and as farmers they ate a completely different diet to the hunter-gatherers that they displaced as the analyses of the prehistoric bone fragments show.
Then 5,000 years ago, the next population turnover occurred, when people of the Corded Ware culture, with their genetic background in Eastern Europe, entered the scene.
“Around 2800 BCE, people of the Corded Ware culture, also called the Single Grave culture, immigrated to Denmark,” says archaeologist Karl-Göran Sjögren.
Genes mixed by the women
It is unclear what happened to the Ertebølle population, but Kristian Kristiansen and Karl-Göran Sjögren each have slightly different hypotheses:
One is that they retreated to Norway and there they continued their hunting and fishing lifestyle, but that some may have isolated themselves in places of refuge where they survived for a few generations.
“Concerning the farming people, also called the Funnelbeaker culture, it appears that their women in particular married men from the immigrant groups, while the male genes from the Funnelbeaker culture population eventually disappeared entirely,” Kristiansen says.
“The analyses show that this was a violent clash of cultures because the Corded Ware people wiped out the farmers from Anatolia relatively quickly. Almost as effectively as when the Funnelbeaker culture had wiped out the hunters and gatherers 900 years earlier.
Contact:
Kristian Kristiansen, Phone: +46(0)704-18 57 67, e-mail: kristian.kristiansen@archaeology.gu.se
Karl-Göran Sjögren, Phone: +46(0)31-786 5264, e-mail: karl-goran.sjogren@archaeology.gu.se
Four articles in Nature
Population Genomics of Postglacial Western Eurasia (Allentoft et al.)
The Selection Landscape and Genetic Legacy of Ancient Eurasians (Irving-Pease et al.)
100 Ancient Genomes Show Repeated Population Turnovers in Neolithic Age Denmark (Allentoft et al.)
Two of the articles in Nature are related to the research project RISE II, which is funded by the Bank of Sweden Tercentenary Foundation (RJ) and is a collaboration between the Department of Historical Studies at the University of Gothenburg, the University of Copenhagen, and the Lundbeck Foundation GeoGenetics Centre. The other two articles in Nature on the Stone Age use material from the long-standing collaboration between the University of Gothenburg and the University of Copenhagen in the research projects RISE I and RISE II. This was a collaboration that began in 2011.
