Britain Wasn’t Always an Island: The Drowned World Beneath the North Sea
The North Sea was not always there. Before the water arrived, before the English Channel cut Britain off from continental Europe, there was land. Dry, forested, inhabited land. Scientists call it Doggerland, named for the Dogger Bank where North Sea fishermen have long dredged up prehistoric bones and tools. For years, researchers assumed this landmass was mostly treeless tundra during the last Ice Age: a flat and wind-scoured corridor that people crossed to reach Britain rather than a place they chose to settle. A major study published in March 2026 in the Proceedings of the National Academy of Sciences overturned that assumption. Doggerland had forests. It had them much earlier than anyone expected. And it may have been a heartland of prehistoric life in northwestern Europe.
The study was led by Professor Robin Allaby of the University of Warwick. It drew on an approach called sedimentary ancient DNA, or sedaDNA, which involves extracting genetic material directly from marine sediment rather than from bones, tools, or other physical artifacts. The team analyzed 252 samples from 41 sediment cores drilled from the bed of the North Sea, concentrating on a prehistoric river system called the Southern River, a waterway roughly 20 miles long that once flowed through southern Doggerland. What the DNA told them changed the picture of this lost landscape entirely.
What the DNA Actually Found
Temperate trees, including oak, elm, and hazel, were already growing in southern Doggerland more than 16,000 years ago. This was roughly the same time that ice sheets still reached as far south as the modern border between Scotland and England. The British mainland was largely tundra. Doggerland was not. The researchers also detected DNA from lime trees (Tilia), a warmth-loving species, which appeared in Doggerland around 2,000 years before any mainland British records show them. More striking still, they found DNA from Pterocarya, a walnut-related genus previously thought to have vanished from northwestern Europe around 400,000 years ago.
The methodology was careful. The team separated secure from insecure sediment samples. Fine silts and clays held DNA deposited locally, meaning it came from plants and animals that actually lived near that spot. Coarser sands were excluded because they carry DNA transported from elsewhere. With that filter in place, 95 to 98 percent of the recovered DNA in reliable samples was estimated to have originated from nearby organisms. In those secure samples, the forest evidence was consistent: oak, elm, hazel, alder, willow. Wild boar DNA backed this up further, since boar require woodland cover and a reliable food supply. Doggerland was not a bleak plain. It was a working ecosystem.
Professor Allaby described the scope of the project simply: this was, to his knowledge, the largest sedimentary DNA study that had been done. The results changed what researchers thought was possible not just for Doggerland but for any submerged landscape.
