A groundbreaking new study confirms that the now-submerged landmass of Doggerland, once connecting Britain to continental Europe, was a surprisingly habitable environment during the last ice age. Analysis of ancient DNA preserved in North Sea sediments reveals that temperate forests flourished in southern Doggerland as early as 16,000 years ago—thousands of years before similar ecosystems re-established themselves elsewhere in northwestern Europe.
Doggerland: A Forgotten Ecosystem
For decades, scientists knew Doggerland existed, but its exact conditions remained unclear. The prevailing theory suggested that the region was frozen tundra during much of the late Pleistocene. However, the new research overturns this assumption, showing that oak, elm, and hazel trees thrived there for millennia before the landmass vanished beneath the waves. The study also suggests Doggerland may have been fully submerged around 6,000 years ago—a timeline that pushes back previous estimates by at least a millennium.
How Ancient DNA Revealed the Truth
Researchers led by Robin Allaby of the University of Warwick analyzed 252 sediment samples extracted from 41 cores drilled from beneath the North Sea. The key innovation was differentiating between “secure” and “insecure” DNA. Fine silts and clays trapped local genetic material, while coarser sands and gravels carried DNA from distant sources. This rigorous filtering allowed them to reconstruct Doggerland’s ecosystem with unprecedented accuracy.
The findings are significant because they demonstrate that pockets of temperate forest survived much further north than previously thought. This has implications for understanding how species migrated after the ice age, and where early human populations may have settled.
Unexpected Species and a Potential “Microrefuge”
The DNA analysis also uncovered surprising species. Researchers found evidence of an extinct walnut relative (Pterocarya ) not seen in the region for 400,000 years, and traces of warmth-loving lime trees (Tilia ). This suggests southern Doggerland was a relatively mild environment even during glacial periods.
The discovery potentially resolves Reid’s paradox, the mystery of how trees recolonized northern regions so quickly after the ice age. Doggerland, or another similar area, may have acted as a “microrefuge” where temperate species survived, allowing them to spread north faster than if they had only persisted in warmer regions like the Iberian Peninsula.
Implications for Human Settlement
The study has broader implications for understanding early human migration patterns. The findings indicate that Stone Age people would have had abundant resources in southern Doggerland after the ice retreated around 21,000 years ago. River mouths would have been prime settlement locations, providing access to food and water.
“Our knowledge is very imprecise,” admits Allaby. “This is not pure tundra—there is enough of an environment here to sustain something that looks like a forest.”
The research underscores that our understanding of prehistoric landscapes is incomplete, and that further exploration could reveal new insights into the past. The submerged world of Doggerland remains a frontier of discovery.
