Hidden forests thrived in the North Sea's lost land earlier than believed

Turns out the lost land beneath the North Sea wasn't just a bridge — it was a thriving forest for humans and animals thousands of years earlier than anyone imagined. New research using ancient DNA has rewritten the timeline for this submerged landscape, known as Doggerland. Scientists now believe temperate trees covered parts of it far earlier than previous records showed, suggesting it was a vital refuge for life.

For centuries, Doggerland connected Britain to mainland Europe before rising sea levels swallowed it, creating the North Sea we know today. While experts knew forests eventually grew there, the exact timing and how hospitable it was for early humans remained a mystery. Now, a large study led by researchers at the University of Warwick analyzed sedimentary ancient DNA (sedaDNA) from deep under the waves. Their findings are pretty remarkable: species like oak, elm, and hazel were present more than 16,000 years ago. That's thousands of years earlier than what pollen records from Britain had suggested.

Even wilder! The team found DNA from Pterocarya, a relative of the walnut tree. Scientists thought this tree vanished from northwestern Europe about 400,000 years ago. Its presence in Doggerland shows it survived there much longer than anyone thought possible. This implies Doggerland wasn't just a temporary stop, but a stable, forested haven.

The data also show that parts of Doggerland stayed above water during major flooding events, including the massive Storegga tsunami around 8,150 years ago. Some areas even persisted until roughly 7,000 years ago. Professor Robin Allaby, lead author from the University of Warwick, explained, "By analyzing sedaDNA from Southern Doggerland at a scale not seen before, we have reconstructed the environment of this lost land from the end of the last Ice Age until the North Sea arrived. We unexpectedly found trees thousands of years earlier than anyone expected." He added that this is the best evidence yet that Doggerland's wooded environment could have supported early Mesolithic communities before the flooding. This could also help explain why so little early Mesolithic evidence survives on mainland Britain today.

To uncover these secrets, researchers took 252 samples from 41 marine sediment cores along Doggerland's prehistoric Southern River. This riverbed was chosen because its sediments were well-preserved, like a time capsule. The samples allowed them to piece together the ecological story of Doggerland from about 16,000 years ago until it went under. The discovery of temperate woodland species thriving so early supports the idea of "microrefugia" — small, protected areas where plants survived the harsh Ice Age conditions in northern Europe. This helps solve "Reid's Paradox," which puzzled scientists about how trees recolonized the region so quickly after the Ice Age.

The presence of these rich woodland habitats 16,000 years ago means Doggerland offered plenty of resources for humans, including forest animals like boars. This was long before the widely recognized Maglemosian culture emerged around 10,300 years ago. Co-author Professor Vincent Gaffney at the University of Bradford put it well: "For many years, Doggerland was often described as a land bridge, only significant as a route for prehistoric settlement of the British Isles. Today, we understand that Doggerland was not only a heartland of early human settlement, but also that the presence of the land mass may have provided a refuge for plants and animals." This deeper look at Doggerland helps us piece together a more complete picture of prehistoric Europe, reminding us how much history is still waiting beneath the waves.