Viking Genes data helps rewrite the history of prehistoric Orkney with ancient DNA
Research, including ORCADES and Viking Health Study - Shetland data, has used ancient DNA to rewrite the history of the Orkney Islands.
The project was a close collaboration between genetic researchers at the University of Edinburgh and Huddersfield. It was led by Professor Martin Richards and Doctor Ceiridwen Edwards, and archaeologists living and working on Orkney.
Yet, over the following thousand years, as Europe moved into the Bronze Age, it has always seemed that Orkney somehow got left behind. Its influence dwindled. The islands became more isolated. However, with fewer archaeological remains to study, much less was known about this time.
In this project, researchers combined archaeology with the study of ancient DNA from Bronze Age human remains from the Links of Noltland site, on the remote northern island of Westray. This has allowed them to learn much more about this time. The results have come as a great surprise to geneticists and archaeologists alike.
What was found?
Despite the supposed isolation, the team showed that Orkney experienced large-scale immigration during the Early Bronze Age. It replaced much of the local population. The new arrivals were probably the first to speak Indo-European languages. They carried genetic ancestry derived, in part, from pastoralists living on the steppe lands north of the Black Sea.
This mirrored what was happening in the rest of Britain and Europe in the third millennium BC. However, the researchers found a fascinating difference that makes Orkney highly distinctive.
Across most of Europe, the expansion of pastoralists on the eve of the Bronze Age was typically led by men. Women were sucked into the expanding populations from local farming groups. However, in Orkney, the researchers found exactly the opposite. The Bronze Age newcomers were mainly women. Male lineages from the original Neolithic population survived for at least another thousand years – something not seen anywhere else. These Neolithic lineages, however, were replaced from the Iron Age, and are vanishingly rare today.
"It's absolutely fascinating to discover that the dominant Orcadian Neolithic male genetic lineage persisted at least 1000 years into the Bronze Age, despite replacement of 95% of the rest of the genome (by immigrating women). This lineage was then itself replaced and we have yet to find it in today's population."
Why was Orkney so different?
Doctor Graeme Wilson and Hazel Moore of the Orkney-based EASE Archaeology excavated the Links of Noltland. They argue that the answer may lie in the long-term stability and self-sufficiency of farmsteads on Orkney. Genetic data suggest they may have already been male-dominated by the peak of the Neolithic. When a Europe-wide recession hit towards the end of the Neolithic, they may have been uniquely placed to weather harsher times. This means they were able to maintain their grip on the population as newcomers arrived.
This implies that Orkney was much less isolated than has long been assumed. It shows there was a long period of negotiation between the indigenous males and the newcomers from the south, over many generations.
This shows that the third-millennium BC expansion across Europe was not a monolithic process but was more complex, and varied from place to place.
The results were surprising for both the archaeologists and geneticists on the team. Archaeologists did not expect such large-scale immigration, whereas the geneticists did not foresee the survival of the Neolithic male lineages.
It shows how much we still have to learn about one of the most momentous events in European prehistory – how the Neolithic came to an end.
The research was published in the Proceedings of the National Academy of Sciences of the USA. It was funded by MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh. It was also part of a Leverhulme Trust Doctoral Scholarship programme awarded to Prof Richards and Dr Pala, and the excavations at the Links of Noltland were funded by Historic Environment Scotland.
Ancient DNA at the edge of the world: Continental immigration and the persistence of Neolithic male lineages in Bronze Age Orkney
Photographs: Graeme Wilson