TÜBINGEN, Germany – Scientists are transforming our understanding of prehistory by extracting and sequencing ancient DNA aDNA directly from cave sediments, turning the dirt beneath our feet into a vast “biological time capsule.” This advancement, known as palaeogenetics, offers a new way to reconstruct Ice Age ecosystems and human presence without relying on bones or artifacts.
The revolution in aDNA analysis, fueled by massive technological leaps in sequencing and robotics, is enabling researchers to ask questions previously impossible, such as whether Neanderthals and modern humans overlapped in the same caves.
The Power of Sediment DNA
For decades, palaeogenetics depended on the physical remains of humans and animals to sequence genomes, which led to discoveries like the interbreeding of Neanderthals and modern humans. Now, researchers can bypass those rare finds:
• Ancient Archives: Caves provide natural DNA archives where stable conditions preserve fragile biomolecules for tens of thousands of years. The oldest sediment DNA discovered so far, from Greenland, dates back two million years.
• Deciphering the Past: The new method allows scientists to reconstruct entire ecosystems, tracking shifts in animal and microbial populations over time. This offers insights into ancient extinctions and ecological consequences relevant to today’s biodiversity crisis.
• Human-Animal Interactions: Researchers at the Geogenomic Archaeology Campus Tübingen GACT in Germany are currently analyzing DNA from the droppings of a cave hyena that lived in Europe around 40,000 years ago.
GACT Leads Global Research Push
GACT is a collaborative network of archaeologists, geoscientists, and aDNA specialists working to establish these new methods. Their research focuses on sites like the UNESCO World Heritage caves of the Swabian Jura including Hohle Fels, home to the world’s oldest musical instruments and figurative art.
The work is logistically challenging, requiring ultra-clean laboratories and sophisticated bioinformatics to identify authentic Ice Age DNA fragments amidst modern contamination.
“Every positive identification is a small triumph, revealing patterns invisible to conventional archaeology,” wrote Gerlinde Bigga from the University of Tübingen.
The network extends globally, with recent fieldwork in Serbia and future expeditions planned for South Africa and the western United States, aiming to test the limits of DNA preservation in different environments. With hundreds of samples now being processed, researchers anticipate major discoveries soon, including the first cave bear genomes and the earliest traces of human activity.
This research, recognized globally with the 2022 Nobel Prize in Physiology or Medicine awarded to pioneering palaeogeneticist Svante Pääbo, promises to unlock a richly detailed genetic history of Ice Age Europe and beyond.