Escoural Cave, Évora.
Genetic remains have been recovered from cave paintings, bones, sediments and tools. First evidence of preservation of human DNA in cave walls for thousands of years helps to understand “how human populations used caves and where they left their traces“.
A scientific project identified Human DNA at least 2,000 years old on cave walls in Spain and Portugal, demonstrating that cave surfaces can preserve human genetic remains for thousands of years.
The study explored the possibility of recovering ancient DNA directly from cave paintings, in addition to traditionally used sources such as bones, sediments or, more recently, bone tools.
Thus, the investigation focused on 24 rock art panels belonging to eleven different caves, including simple lines, negative handprints and pigments from some figures from the cave of Altamira (Cantabria).
Using cutting-edge techniques for DNA extraction and sequencing, the team analyzed wall fragments with and without pigment, sediment, bones and a prehistoric airbrush tool used to apply paint.
Although researchers have detected ancient human DNA in a pigmented calcite crust from Escoural Cave, in Montemor-o-Novo, Évorathe surprising and unprecedented discovery was the presence of ancient human DNA also in several non-pigmented areas of the walls of the Escoural and Covarón Caves (Asturias, Spain)which had initially been sampled as negative controls.
“While we cannot directly link traces of ancient human DNA found to the creation of rock art, This is the first evidence of preservation of human DNA in cave walls for thousands of years“, highlighted Alba Bossoms Mesafirst author of the study, from the Max Planck Institute for Evolutionary Anthropology.
Second Hipolito Colladohead of the Archeology section of the General Directorate of Cultural Heritage of the Regional Government of Estremadura, the discovery not only refers to rock art, but also “to understanding how human populations used caves and where they left their traces”.
The recovered ancient human DNA is at least 2000 years old, demonstrating that these surfaces can preserve biological traces for long periods. This discovery opens a new frontier in archaeogenetics.
Specifically, the biological remains in three of the samples are from women, while one corresponds to a male individual and the sex of another could not be determined.
Scientific team believes cave walls could become real “biological archives” of ancient human activity, which will allow future analyzes of other sites and artistic styles using minimally invasive techniques.
The work was carried out in collaboration with teams from Spain, Portugal, the United Kingdom, Germany and China. The research was carried out at Nature Communications and is part of the FIRST ART project, which originated from research into rock art in the Maltravieso Cave (Cáceres), where the oldest pictorial representations in Europe were identified.
With the experience gained, this project expanded to other territorial areas to date the oldest artistic expressions in the Iberian Peninsula and characterize their chemical composition. So, in collaboration with researchers at the Max Planck Institute for Evolutionary Anthropology in Germany, the team expanded their research to include DNA analysis.
