2,000-year-old human DNA found in caves in Spain, Portugal

An international team of researchers has discovered human DNA at least 2,000 years old on cave walls in Portugal and Spain, providing the first evidence that cave walls can preserve human genetic material for thousands of years.

According to a report by Lusa News Agency on Thursday, using advanced DNA extraction and sequencing techniques, the researchers detected ancient human DNA in a pigmented calcite crust from Escoural Cave in Portugal, as well as in several unpigmented cave wall samples from Escoural Cave and Covaron Cave in Spain.

The team recovered five authentic ancient human DNA samples, all dating back at least 2,000 years, the report said.

The researchers said the findings provide the first evidence that ancient human DNA can survive on cave walls for thousands of years. In the future, analysis of DNA preserved on cave walls may help reveal the biological sex, genetic ancestry and movement of people who once entered the caves, without disturbing archaeological deposits.

The team told the media that cave walls could serve as biological archives of prehistoric human activity, offering a new approach to understanding how prehistoric people used caves and to investigating the identity of the creators of some cave art.

(Cover: The La Pileta cave in Benaojan, near Malaga, Spain. /VCG)