Researchers extracting nuclear DNA from 22,000-year-old sediment in Spain’s El Mirón Cave have recovered genetic material from an era with no human remains in that layer, mapping human lineage without bones or teeth. The sample weighed no more than a few grains of rice.
Ice Age Europeans Were More Connected Than We Thought
A team of paleogeneticists published findings in Science Advances showing that eastern and western European populations were less isolated during the Late Stone Age than previously assumed. The Gravettian culture, spanning roughly 33,000 to 22,000 years ago, clustered into distinct western and eastern genetic groups before genomic sequencing blurred those boundaries. Researchers extracted DNA from Gravettian individuals across Europe, including a woman in Isturitz Cave in southwestern France who provided the oldest complete genome in the region to date. Her DNA revealed mixed ancestry showing East-West exchange around 30,000 years ago.
Sediment DNA Unlocks Missing Prehistory
The El Mirón Cave sediment sample contained DNA from ancient humans during Europe’s last ice age. Ron Pinhasi of the University of Vienna stated that sedimentary DNA recovers genetic information from periods where human remains are missing and connects archaeological layers with genetic ancestry. Earlier studies suggested separate ancestry in eastern and western Europe, but the new genomic data from Isturitz Cave and Spanish cave dirt challenges that model by pointing to long-distance gene flow.
Tracing Population Continuity Through the Last Glacial Maximum
To examine human migration, lead author Pere Gelabert and colleagues compared the El Mirón nuclear DNA to an ancient woman in France living roughly 31,000 years ago and a northern Spanish tooth dated to about 25,000 years ago. Both individuals showed signs of eastern ancestry, indicating interbreeding before the last glacial maximum. However, the 22,000-year-old El Mirón DNA showed only western ancestry, leading researchers to conclude that the population in southwest Europe remained relatively continuous without major replacement. All three newly sequenced Gravettian genomes displayed genetic traits suggesting dark skin, hair, and eyes.
How Scientists Extract DNA from Cave Sediment?
How do scientists extract human DNA from cave dirt without bones?
Researchers sift through sediment samples to isolate trace amounts of DNA.
What did the genetic analysis reveal about Ice Age migration routes?
Genomic data from Isturitz Cave in southwestern France showed that a pulse of gene flow occurred between eastern and western European populations around 32,500 to 31,500 years ago.
Did the El Mirón Cave DNA show evidence of eastern ancestry?
While older samples from the region showed mixed ancestry, nuclear DNA from El Mirón Cave displayed only western ancestry, supporting regional population continuity through the Last Glacial Maximum.
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