The Archaeology of Touch: Can a Fingerprint Leave DNA for Thousands of Years?
A genetic trace on Panel 11
On a calcite crust associated with pigment at Panel 11 in Escoural Cave, southern Portugal, researchers found something that archaeologists have long hoped might survive on a decorated cave wall: ancient human DNA.
The quantities were small. Two extracts from the sample produced 526 and 436 hominin mitochondrial DNA molecules, respectively. More important than the number of fragments was their condition. Many carried characteristic chemical damage, particularly cytosine-to-thymine substitutions concentrated towards the ends of the molecules, one of the signatures used to distinguish genuinely ancient DNA from recent contamination. Targeted analysis indicated that the ancient sequences belonged to Homo sapiens. No ancient faunal mitochondrial DNA was detected in the sample.
That last observation is central to the argument made by Alba Bossoms Mesa and colleagues in their 2026 Nature Communications study. Cave sediments normally contain a genetic mixture. Humans, large mammals, small mammals and other organisms all contribute DNA that can subsequently move through sediment or water. Yet in the Panel 11 sample the detectable ancient mammalian signal was human alone. The researchers found the same pattern in an unpigmented wall sample elsewhere at Escoural. They therefore regard direct human deposition, through touching, rubbing or bodily fluids, as the most likely explanation.
“Most likely” matters.
No prehistoric fingerprint was identified on the wall. Nobody has matched DNA to a painted hand stencil. The study has not found the genetic identity of a particular Palaeolithic artist. Nor can it demonstrate that the DNA and pigment were deposited during the same episode.
What it does show is both less spectacular and potentially more useful: human DNA can persist on cave walls for thousands of years, and in favourable circumstances its composition may be consistent with direct human contact.
That changes the range of surfaces that palaeogeneticists can reasonably investigate.
What does a touch actually leave behind?
The expression “touch DNA” comes largely from forensic science. When a person handles an object, biological material may be transferred to it. That material can include cellular and extracellular DNA associated with skin contact and bodily secretions. Modern analytical techniques can sometimes obtain genetic profiles from quantities far below anything visible to the eye.
A fingerprint and touch DNA, however, are not interchangeable terms.
A fingerprint is a patterned physical or chemical trace produced by friction ridges on the fingers. DNA is molecular material deposited during or around the same act. One can occur without the other. A surface may preserve DNA without retaining recognizable ridge detail, and a beautifully preserved fingerprint impression need not preserve the biological material originally deposited with it.
The distinction becomes particularly important archaeologically. Fingerprints impressed into wet clay can survive because the clay records the shape of the fingertip. Once fired, the impression becomes part of the ceramic surface. What survives is effectively a mould of a moment of contact. The organic material transferred by that finger has a quite different preservation history.
This is why prehistoric pottery already contains an archaeology of touch even without DNA. Finger and palm impressions have been studied on ceramics, figurines and clay objects to investigate participation in craft production. At Early Bronze Age Tell eṣ-Ṣâfi/Gath in Israel, for example, Kent Fowler and colleagues analysed more than a hundred fingerprints on pottery dating to about 2700–2600 BC. Patterns of ridge breadth and density were used to investigate whether adults, adolescents and children participated in different stages of manufacture, and multiple prints on individual vessels were interpreted as evidence for cooperative production and perhaps learning.
Such demographic interpretation is not methodologically settled. A 2024 critique by Akiva Sanders and Andrew Burchill argued that some widely used combinations of ridge breadth and ridge density treat two mathematically related measurements as though they were independent and may consequently assign age and sex with unjustified precision. Archaeological fingerprints remain direct traces of handling, but the biological profile reconstructed from them can be considerably less certain than the survival of the print itself.
This provides a useful warning for the genetics of touch. Better analytical resolution does not automatically produce a more secure archaeological interpretation.
From cave sediment to the surface of an artefact
The Escoural experiment belongs to a broader change in ancient-DNA research. Human remains were once effectively indispensable for palaeogenomics. That is no longer the case.
In 2017, Viviane Slon and colleagues showed that mitochondrial DNA from Neanderthals and Denisovans could be recovered from Pleistocene cave sediments even where identifiable hominin bones were absent. Later work demonstrated that such DNA can remain localized within microscopic sedimentary contexts rather than simply forming an undifferentiated genetic haze throughout a cave deposit.
The conceptual step is important. Archaeologists are no longer restricted to asking which body produced a genome. They can ask where genetic material was deposited, what kind of surface retained it and what human activity might have brought it there.
Artefacts offer an even closer association.
In 2023, Elena Essel and colleagues reported ancient human DNA from a perforated elk tooth pendant excavated in Denisova Cave. Using a non-destructive phosphate-based extraction technique, they obtained sufficient mitochondrial and nuclear DNA to infer that much of the deeply retained human genetic material came from a female individual genetically related to Ancient North Eurasians. Genetic estimates placed the pendant broadly around 19,000–25,000 years ago.
Even there, the researchers described the woman cautiously as the presumed maker or wearer. An ornament may pass between people. Someone can manufacture an object without wearing it; someone else may wear it for years. Human DNA on an artefact establishes a biological association before it establishes a social role.
Escoural pushes the problem one stage further. A wall cannot be carried away, but it can be touched repeatedly across centuries or millennia.
A cave used more than once
Escoural is particularly instructive because its archaeological history refuses to provide a simple answer.
The cave contains Middle and Upper Palaeolithic evidence, Neolithic burials and Chalcolithic activity. It was subsequently sealed and was not reopened until quarrying exposed it in 1963. That history gives the ancient wall DNA a useful minimum age. The authors conclude from the site's closure that the relevant Escoural DNA must be at least roughly 4,000–5,000 years old. Molecular damage is compatible with a considerably greater age, but does not provide a precise date.
The pigment associated with the DNA-positive Panel 11 sample looks stylistically compatible with Palaeolithic marks. Unfortunately, comparable motifs also occur later. The genetic material itself could not be dated closely enough to demonstrate contemporaneity with the pigment. Its mitochondrial lineage could be narrowed only to the broad haplogroup N and descendants, and the nuclear data were too sparse for reliable population-genetic analysis or biological sex estimation.
Consequently, several histories fit the observation.
A person could have deposited DNA while making the mark. A second person could have touched the freshly painted surface. Someone could have touched it centuries later. The wall might have been rubbed deliberately during some activity unrelated to image-making. A person squeezing through the cave might simply have steadied themselves against the rock.
All would produce an archaeological association between human DNA and a painted surface. Only the first would identify the genetic contributor as an artist.
The evidence is therefore less straightforward than the headline suggests, and the researchers themselves make that distinction explicitly: their results do not conclusively connect ancient human DNA with the production of cave art.
When DNA identifies presence rather than authorship
The unpainted surfaces may ultimately prove as interesting as the painted ones.
The project sampled 24 rock-art panels from eleven Iberian caves, including simple red marks, hand stencils and figurative art, alongside unpigmented controls. Ancient human DNA appeared in only one of the 24 sampled art panels. Four additional positive samples came from unpigmented cave walls at Escoural and Covarón.
Two Covarón wall samples contained enough nuclear DNA for broader genetic comparison. Their sequences clustered with western European hunter-gatherers, close to the genetic variation represented by groups such as Villabruna and Oberkassel. Yet these samples came from unpigmented surfaces near art, not demonstrably from the production of the art itself.
That result suggests a research programme rather different from the search for named “artists”.
Cave walls might eventually record who moved through different parts of a subterranean landscape. Genetic traces could potentially distinguish areas visited by different populations, identify whether human activity reached deep galleries lacking substantial floor deposits, or perhaps show that some spaces were frequented disproportionately by people of one biological sex.
Such interpretations would require extensive spatial sampling rather than a spectacular result from a single painting. In effect, the cave wall would be treated as another archaeological deposit, one whose evidence happens to accumulate horizontally across stone rather than vertically through sediment.
The comparison with sedimentary DNA is apt. The first detection of hominin DNA in cave sediment did not mean that every DNA molecule could immediately be assigned to a particular occupation event. Its value increased as researchers learned how genetic material moves, binds to minerals and survives within stratigraphic microcontexts. Cave-wall DNA will require a similar taphonomic archaeology.
The contamination paradox
The extraordinary sensitivity of ancient-DNA methods creates their greatest difficulty.
Objects that archaeologists have valued most are often precisely those that have been touched most since excavation: lifted by excavators, passed between specialists, photographed, drawn, conserved, exhibited and handled during decades of study.
Essel's work on Palaeolithic bone and tooth artefacts illustrated the problem starkly. Objects excavated long ago and subsequently handled produced overwhelming quantities of recent human DNA; in the tested Quinçay material, modern contamination accounted for roughly 71 to 98 per cent of identified human mitochondrial sequences. Freshly excavated objects recovered with gloves and masks performed much better.
The 2026 cave-wall project faced the same problem. Researchers used gloves, masks, disposable protective equipment and sterile instruments. Even so, the Panel 11 extracts contained substantial present-day human contamination. Authentication therefore depended not merely on finding “human DNA” but on demonstrating molecular damage characteristic of ancient sequences and analysing fragments in ways that reduced the influence of modern molecules.
An Altamira bird bone interpreted as a prehistoric pigment-blowing tube provides an almost cruel example. If pigment had been blown through it by mouth, saliva might once have made the artefact an excellent candidate for identifying its user. No ancient human DNA was recovered. The object had accumulated extensive present-day contamination, while conservation requirements restricted how much material could be sampled.
This has implications for excavation practice now. Archaeologists cannot know which objects will become suitable for methods invented twenty years from today. Gloves, masks, clean storage and minimal handling are therefore no longer precautions relevant only to human bones. Selected ornaments, tools, pigments, mineral crusts and other objects likely to have been handled should increasingly be regarded as potential molecular archives. Contamination control beginning at excavation is much more effective than attempting to subtract decades of modern contact later.
There is another complication. Modern forensic studies show that DNA can be transferred secondarily. A person's DNA on an object does not necessarily prove that the person touched it directly. Biological material may move via hands, clothing, sediment, tools or other surfaces.
In a cave, the equivalent processes operate over archaeological timescales. Someone can touch the floor and then the wall. Water can redistribute DNA. Sediment can adhere to hands or stone. This is probably why several of the positive Iberian wall samples contained both human and animal DNA: their molecular composition resembled the mixed signal expected from sedimentary transfer.
What would it take to identify an artist?
A convincing genetic identification of a rock-art maker would require much more than human DNA beneath a headline.
Ideally, DNA would be recovered reproducibly from the pigment-bearing micro-layer while neighbouring unpainted controls remained negative or genetically distinct. Samples from above and below a carbonate crust could establish the relative sequence of deposition. Uranium-series dating of the carbonate might constrain when the pigment was sealed. The DNA itself would need enough endogenous material for genetic characterization and authentication. Replicate sampling would have to show that the signal was localized rather than broadly distributed across the wall.
Most importantly, chronology would have to connect the genetic deposition with the artistic event.
The Escoural team explicitly proposes this kind of microstratigraphic approach. At Panel 11 they analysed numerous additional subsamples after the original positive result, including material targeted separately within the crust. None produced further ancient hominin DNA, indicating that the initial signal occupied only a very restricted area. That result does not invalidate the DNA; it demonstrates how patchy its preservation can be.
If future work recovered one genetic profile concentrated specifically within an image layer and absent from surrounding wall surfaces, securely bracketed by dated mineral deposits, the argument for participation in making the image would become much stronger. Even then, “maker” might remain safer than “artist”. Pigment preparation, application and retouching need not have been performed by the same person.
The archaeological record rarely gives up social identities as neatly as modern language would like.
For now, then, the answer to the editorial question is qualified. A human touch can leave DNA that survives for thousands of years. The Escoural evidence makes that proposition substantially stronger than it was before. But no ancient fingerprint has yet been genetically matched to the individual who painted a Palaeolithic cave wall.
The next problem is no longer simply whether DNA survives on stone. It is whether archaeologists can reconstruct the sequence of contacts closely enough to distinguish the hand that made an image from all the hands that came afterwards.
Selected Sources and Further Reading
Bossoms Mesa, A., Essel, E., Jáuregui, L., et al. 2026. “Investigating ancient human DNA preservation on cave walls and in rock art.” Nature Communications 17, 5561.
https://doi.org/10.1038/s41467-026-74234-2
Essel, E., Zavala, E. I., Schulz-Kornas, E., et al. 2023. “Ancient human DNA recovered from a Palaeolithic pendant.” Nature 618: 328–332.
https://doi.org/10.1038/s41586-023-06035-2
Slon, V., Hopfe, C., Weiß, C. L., et al. 2017. “Neandertal and Denisovan DNA from Pleistocene sediments.” Science 356: 605–608.
https://doi.org/10.1126/science.aam9695
Massilani, D., Morley, M. W., Mentzer, S. M., et al. 2022. “Microstratigraphic preservation of ancient faunal and hominin DNA in Pleistocene cave sediments.” Proceedings of the National Academy of Sciences 119: e2113666118.
https://doi.org/10.1073/pnas.2113666118
Fowler, K. D., Ross, J., Walker, E., Barritt-Cleary, C., Greenfield, H. J. & Maeir, A. M. 2020. “Fingerprint evidence for the division of labour and learning pottery-making at Early Bronze Age Tell eṣ-Ṣâfi/Gath, Israel.” PLOS ONE 15(4): e0231046.
https://doi.org/10.1371/journal.pone.0231046
Sanders, A. & Burchill, A. T. 2024. “Mean ridge breadth and ridge density tell the same story for ancient fingerprints: A critique of the ‘Age-Sex Identification Matrix’ method of demographic reconstruction.” Journal of Archaeological Science 169: 106036.
https://doi.org/10.1016/j.jas.2024.106036
Llamas, B., Valverde, G., Fehren-Schmitz, L., Weyrich, L. S., Cooper, A. & Haak, W. 2017. “From the field to the laboratory: Controlling DNA contamination in human ancient DNA research in the high-throughput sequencing era.” Science and Technology of Archaeological Research 3(1): 1–14.
https://doi.org/10.1080/20548923.2016.1258824
van Oorschot, R. A. H., Szkuta, B., Meakin, G. E., Kokshoorn, B. & Goray, M. 2019. “DNA transfer in forensic science: A review.” Forensic Science International: Genetics 38: 140–166.
https://doi.org/10.1016/j.fsigen.2018.10.014
Suggested keywords
ancient DNA; touch DNA; Escoural Cave; cave art; rock art; archaeogenetics; Palaeolithic art; archaeological fingerprints; palaeodermatoglyphics; DNA contamination; sedimentary DNA; artefact DNA
Editorial summary
The recovery of ancient human DNA from Iberian cave walls turns physical contact itself into a potential archaeological record, while forcing a crucial distinction between demonstrating that someone touched a surface and proving who created the image upon it.