Credit: Adapted from ACS Omega 2026, DOI: 10.1021/acsomega.6c05061
Tucked away inside a limestone cave in southeastern France lies some of the oldest artwork in existence. Known as Chauvet Cave, the site is so historically important — and fragile — that its location is kept secret and locked behind a huge steel door. And now, researchers reporting in ACS Omega have devised a technique to safely investigate these artworks and understand the natural varnish that has protected them for centuries.
“We examine every piece of evidence to decode the techniques of prehistoric artists and understand how the paintings have been preserved over time.” — Philippe Walter
Somewhere around 37,000 years ago, a group of Paleolithic people entered what is now Chauvet Cave and left behind detailed artwork of local fauna, including cave bears, cave lions, bison, and horses. The drawings were sealed off by an ancient rockfall and left undiscovered until the 1990s. Several decades later, a lot can still be learned from these ancient works of art, including how the cave’s geology may have contributed to the artworks’ preservation. To study cave walls without damaging them, researchers have used UV fluorescence spectroscopy, which reveals fluorescent mineral deposits invisible to the naked eye. Philippe Walter and colleagues wanted to use the technique to noninvasively investigate these ancient drawings. Their focus was on mineral deposits that have formed atop the charcoal-based drawings and the techniques used to create the art.
Due to the fragility of prehistoric footprints in front of the artwork, the researchers set up a portable spectrometer on a protective walkway around 8 feet (2.5 meters) away from the cave wall. A beam of UV light was shone on the wall, and the resulting fluorescence from the mineral deposits and pigments in the artworks was analyzed by the spectrometer.
“Our methodology is much like forensic investigation: We examine every piece of evidence to decode the techniques of prehistoric artists and understand how the paintings have been preserved over time,” says Walter.
The researchers’ analysis revealed that:
Mineral-carrying water flowed over the wall’s limestone surface, leaving behind thin layers of calcite. That calcite glowed blue under a blacklight, revealing a natural varnish covering parts of the artwork.
Some areas displayed an orange fluorescence, which could be from hot charcoals or burning materials, like a lit torch, being rubbed against the wall to create the drawings.
These results showcase the careful interaction between humans and geology that allowed these artworks to be preserved for tens of thousands of years. Walter and team anticipate that the technique also has applications from forensic science to monitoring biofilms onboard the International Space Station — a project already underway.
Skeletal elements from an infant buried in Salango, Ecuador. (A) Showing lesions (red); grey bones were not recovered. (B) Petrous portion with lytic lesions and new bone formation. (C) Left clavicle and (D) right humerus with new bone plaques. (E) Ribs with lytic lesions and (F) right ilium with a large lytic defect.
Ancient genomes from coastal Ecuador reveal 1,500 years of genetic continuity in an understudied part of the ancient world. John Lindo and colleagues sequenced four genomes from individuals excavated at Salango on Ecuador’s central coast, from around 2,300 years ago, 1,900 years ago, and 740 years ago. The four genomes cluster with ancient and present-day populations from Ecuador, Colombia, and Peru, consistent with shared ancestry within a northwestern South American genetic continuum. The Salango population likely diverged from other Southern Native Americans around 9,800 years ago. All four individuals showed genetic similarities, suggesting population continuity at Salango despite major cultural and environmental changes, including the aftermath of the Pululahua volcanic eruption around 2,360 years ago, the rise of chiefdoms, and the development of maritime and overland trade. In addition, one individual, an infant, exhibited skeletal lesions consistent with tuberculosis. The researchers recovered DNA from the Mycobacterium tuberculosis complex and reconstructed a pathogen genome, providing rare genetic evidence of tuberculosis in the pre-contact Americas. According to the authors, the study opens new opportunities to trace both population history and infectious disease along South America’s Pacific coast.
Journal
PNAS Nexus
Article Title
Ancient Ecuadorian genomes reveal millennia of genetic continuity on the Pacific Coast of South America
More than 30,000 years ago, people associated with one of Europe’s major Palaeolithic cultures (the Gravettian) were more interconnected than previously thought. An international research team led by the University of Vienna has uncovered new genetic evidence of long-distance connections between these populations. Published in Science Advances, the study combines genomic data from rare human remains with human DNA preserved in cave sediments.
The Gravettian culture was widespread across Europe around 34,000 to 25,000 years ago. While archaeological finds have long suggested extensive contacts across the continent, genetic data pointed to relatively stable eastern and western ancestry groups. By analysing new and previously published genomic data alongside human DNA from cave sediments, the researchers found evidence of east-west genetic exchange and long-term population continuity in southwestern Europe.
A woman's genome links east and west
The remains of a woman from Isturitz Cave in southwestern France, who lived around 30,000 years ago, yielded the oldest to date genome-wide dataset of a modern human from southwestern Europe. Her genetic data provide key evidence of east-west exchange: most of her ancestry was related to the western European lineage, but she also carried ancestry related to populations from central and eastern Europe. Genetic modelling dates this gene flow to around 32,500 to 31,500 years ago. "Our results show that eastern and western European populations were not as genetically isolated as previously assumed," says first author Pere Gelabert, Department of Evolutionary Anthropology at the University of Vienna. "Gene flow across such large distances adds a new dimension to our understanding of how Gravettian populations were connected." A similar signal was found in a previously studied individual from Ormesson, France. Together with archaeological evidence, the new findings also support the idea that Isturitz may have been a meeting place for different groups.
Human DNA from cave sediment
At the same time, the researchers found evidence for long-term population continuity in southwestern Europe. Genomic data from ChufÃn Cave in northern Spain indicate that western European ancestry persisted in the region over thousands of years. The team also analysed ancient human DNA preserved directly in cave sediment. At El Mirón Cave in Cantabria, they recovered enough human nuclear DNA from a 22,000-year-old layer to determine its genetic ancestry – despite the absence of human bones or teeth. "Sedimentary DNA allows us to recover genetic information from periods where human remains are missing," says senior author Ron Pinhasi, Department of Evolutionary Anthropology at the University of Vienna, whose team led this study. "This gives us a way to connect archaeological layers with the genetic ancestry of the people who occupied a site." The El Mirón DNA shows that this ancestry persisted through the Last Glacial Maximum, supporting the idea of the Iberian Peninsula as an Ice Age refuge.
What mother and son reveal about mating
In southern Italy, the team analysed Ostuni1b, a male fetus and most likely the son of the previously studied woman Ostuni1. His father probably came from the same genetic population, yet the parents were not closely related – suggesting mating practices that helped avoid high levels of inbreeding. Together, the findings show that regional population continuity could coexist with genetic exchange over large distances. Gelabert's team is now combining sedimentary DNA with advanced proteomic analyses to investigate the first trans-European expansions of modern humans and their interactions with carnivores where organic remains are scarce.
Summary:
New genomic data reveal previously undetected genetic connections between eastern and western Gravettian populations in southwestern Europe.
Genetic modelling dates this gene flow to around 32,500–31,500 years ago.
Human DNA recovered directly from cave sediment traces long-term population continuity even where skeletal remains are missing.
Genetic data from a mother and her son provide clues to population stability and mating practices in Gravettian Italy.
Fukuoka, Japan—Publishing in the journal Proceedings of the Royal Society Ba research team from Kyushu University, Universitetet i Bergen, and the University of Copenhagen reports that they found traces of ancient collagen protein from the common eland, Taurotragus oryx, on a 60,000-year-old ochre-rich surface in the Kilpdrift Complex, a Middle and Later Stone Age archeological site located within the coastal cliffs of the De Hoop Nature Reserve in South Africa.
To better understand how ochre was used by early humans, the team used palaeoproteomics, the high-throughput analyses of ancient proteins, to search for potential proteinaceous traces within this archaeological feature. The study identified collagen from elands in the ochre surface, suggesting that either animal-derived materials were deliberately mixed with the ochre or ochre-treated eland hides were present at the site.
These findings provide new evidence for the complex technical and possibly symbolic behaviors of early Homo sapiens.
The most significant finding is the identification of type I collagen proteins from the common eland, which provides biomolecular evidence that animal-derived materials were associated with ochre use during the Middle Stone Age. Until now, evidence of organic components mixed with ochre has been extremely rare, especially in Africa. This discovery offers a new way to investigate how early humans used ochre and other organic materials in their daily, technical, and potentially symbolic activities.
The team analyzed archived sediment samples taken from the Kilpdrif Complex using palaeoproteomics, a growing field of archaeology and paleontology that examines ancient proteins preserved in materials collected at archeological sites. The proteins were extracted from the sediments and analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The resulting protein fragments were then compared to large protein databases and a custom collagen reference database to identify their species of origin.
These findings demonstrate that palaeoproteomics can successfully recover and identify ancient proteins from archaeological sediments, even in challenging African environments where ancient DNA rarely survives. This creates a powerful new tool for archaeologists studying early human behavior, allowing them to investigate biological materials no longer visible in the archaeological record.
Genetic history of Roman and Late Antique Hispania: An international study has analysed 243 ancient genomes from 31 archaeological sites to reconstruct the population history of the Iberian Peninsula between the 1st and 8th centuries CE.
Roman rule transformed Iberia: The Roman conquest produced large-scale demographic change, turning the peninsula into a genetically diverse population mosaic with widespread ancestry from the eastern Mediterranean and North Africa.
Limited demographic impact of later migrations: The elites of the subsequent Suebian, Alan and Visigothic Migration Period introduced Central and Northern European ancestry, without causing population replacement or major demographic change.
Family histories behind migration: Genomic analysis reveals individual stories of migration, alliances and power, including siblings buried hundreds of kilometres apart and elite women whose identities did not necessarily reflect foreign origin.
An international study led by the Institute of Evolutionary Biology (IBE, CSIC-UPF) in Barcelona, the Natural Sciences Museum of Barcelona, Harvard University and the University of the Basque Country (EHU) has reconstructed the genetic history of the Iberian Peninsula between the 1st and 8th centuries CE using 243 ancient genomes from 31 archaeological sites.
The Iberian Peninsula was one of Rome’s earliest major conquests. Its position between the Atlantic and the Mediterranean, together with its abundant natural resources, made Hispania a key territory for the Empire. Centuries later, the weakening of Roman power facilitated the arrival of the Alans, Vandals and Suebi in 409 CE.
After the fall of the Western Roman Empire, these and other Germanic groups established new kingdoms in various parts of Europe, including the Visigothic Kingdom, founded on the peninsula in 507. Although some were short-lived, these emerging states helped shape medieval political identities and, in the long term, the map of Europe’s future states.
It was, however, still an open question as to whether the profound political and cultural influence of these migrations was accompanied by a demographic transformation of comparable magnitude.
By combining genetic and archaeological evidence, the new study published in Cell has concluded that the Roman conquest of the Iberian Peninsula produced a large-scale demographic change. In contrast, the Suebi, Vandal, Alan and Visigoth migrations in Late Antiquity had a more limited impact on the genetic makeup of Hispania.
Rome turned Iberia into a Mediterranean genetic mosaic
The study, the first systematic, large-scale archaeogenomic analysis of this period, shows that the Iberian population changed profoundly as Roman rule became established. In contrast to the relative genetic homogeneity of the Iron Age, individuals from the 1st to the 4th centuries CE display much greater ancestry diversity.
Roman rule encouraged the arrival of people with eastern Mediterranean and North African ancestry, creating a heterogeneous society connected to human networks across the Mediterranean.
“Romanisation was not only a political, linguistic and cultural transformation. Our data show that it was also a major demographic transformation, connecting local populations with human movements originating in different parts of the Mediterranean”, explains Carles Lalueza-Fox, current director of the Natural Sciences Museum of Barcelona, co-senior author of the study and principal investigator at the IBE (CSIC-UPF).
The new Germanic elites left a mark, but did not radically alter the genetics of the local population
From the 5th century onwards, the study has identified individuals with Central and Northern European ancestry, particularly in archaeological contexts associated with the new political groups. However, most communities retained the diverse profile of the Hispano-Roman population.
“What surprised us most was the contrast between the two processes. Rome created an extraordinarily diverse society due to population movements across the Mediterranean. Later migrations introduced new ancestries, but their demographic impact was much smaller”, says Pablo Carrión, first author of the study, who completed his doctorate at the IBE (CSIC-UPF) and is now a postdoctoral researcher at the Max Planck Institute for Evolutionary Anthropology in Leipzig.
The genetic contribution of these groups ranges from 12 percent to 22 percent, depending on the region and social context. Admixture with local populations was gradual and did not radically alter the genetic landscape, unlike in Britain or the Balkans, where post-Roman migrations had a greater demographic impact.
“The genetic history of the Iberian Peninsula differs from that of other parts of post-Roman Europe. We find migration and new ancestries, but not population replacement or large-scale demographic impact”, says David Reich, principal investigator at Harvard University and co-senior author of the study.
Two family stories reveal migrations, alliances and struggles for power
Their kinship and the archaeological context of their richly furnished burials point to a possible route taken by the Suebian migration. “We are not simply observing changes in genetic frequencies; we are identifying families who moved across a peninsula that was still connected by the infrastructure of the Roman Empire”, explains Iñigo Olalde, co-author of the study and Ikerbasque Research Professor at the EHU.
Other remains, those of the so-called “Suebian princesses”, reveal another side of this process. Although their rich grave goods had led them to be regarded as members of an elite that arrived from beyond the imperial frontiers, one of them had local ancestry. The finding points to marriage alliances between Suebian elites and Hispano-Roman families. The deaths of several of these women within the same period may have been linked to a succession dispute in an elective monarchy.
“These women show how genetics can change our interpretation of past elites: an identity associated with migrant groups, whether Visigothic or Suebian, did not necessarily imply foreign origin, as this could also be acquired through family, political and cultural alliances”, adds Pablo Carrión.
A genetic history that remains incomplete
Iberian populations in Late Antiquity were genetically more heterogeneous than those of the present day. This indicates that the gene pool changed once again during the mediaeval and post-mediaeval periods, shaped by Visigothic rule, the Islamic conquests, internal population movements and the expansion of the Christian kingdoms.
“Future studies of mediaeval and post-mediaeval genomes are essential to connect the peninsula’s ancient inhabitants with its present-day populations, with implications for the historical, cultural and even political fields”, notes Lalueza-Fox. The team also emphasises the need to expand sampling, particularly in the northern Iberian Peninsula and North Africa.
The paper shows that major political changes did not necessarily have equivalent demographic consequences. Rome profoundly transformed the composition of Iberian society; the elites of Late Antiquity, in contrast, exerted a lasting political and cultural influence without replacing the population.
