Secrets of the Drowned Forest: DNA Reveals North Sea’s Lost Woodlands from 400,000 Years Ago

Scientists have uncovered evidence that forests thrived in the North Sea region thousands of years earlier than previously believed, revealing a hidden ecosystem that may have supported human life during the last Ice Age. Using sedimentary ancient DNA analysis, researchers identified DNA from oak, elm, and hazel trees dating back more than 16,000 years ago in what is now submerged beneath the North Sea.

The findings, published in Proceedings of the National Academy of Sciences (PNAS), show that the now-submerged landmass of Doggerland—once a land bridge connecting Britain to continental Europe—hosted temperate forests long before such vegetation became widespread across Britain and northern Europe. This challenges previous assumptions about the timing of forest development in the region following the last glacial period.

Perhaps most remarkably, the study detected genetic material from a tree genus thought to have vanished from the region approximately 400,000 years ago. This discovery indicates that certain tree species persisted in the area far longer than scientists had expected, suggesting localized refuges where flora survived despite broader climatic shifts.

Analysis of sediment cores from Southern Doggerland revealed that parts of the landscape remained above water during significant flooding events, including the Storegga tsunami that occurred around 8,150 years ago. Some areas of Doggerland may have persisted as dry land as recently as 7,000 years ago, gradually disappearing as rising sea levels reshaped the North Sea basin.

According to Professor Robin Allaby of the University of Warwick, who led the research, the study provides the best evidence yet that Doggerland’s wooded environment could have supported early Mesolithic communities prior to its submersion. This may help explain why relatively little archaeological evidence from this period has been found on mainland Britain today, as populations may have been concentrated in the now-submerged region.

The research employed advanced sedimentary ancient DNA (sedaDNA) techniques to reconstruct past environments from microscopic genetic traces preserved in seabed sediments. This method allows scientists to detect plant and animal life without relying solely on fossil records, offering a more detailed picture of ancient ecosystems.

By demonstrating that forests were established in Doggerland millennia earlier than previously thought, the study suggests the region served as a significant refuge for biodiversity during periods of climatic instability. These findings contribute to a growing understanding of how early humans and wildlife adapted to changing landscapes in prehistoric Europe.

The implications of this research extend beyond archaeology and paleoecology, offering insights into how ecosystems respond to sea-level rise and climate change—parallels that resonate with contemporary environmental challenges. As sea levels continue to rise today, understanding how past populations adapted to similar shifts may inform future resilience strategies.