Ancient Human DNA Found in Stone Age Cave Art For First Time

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0:33For the first time, ancient human DNA has been found preserved in cave art that was made thousands of years ago. This is a huge moment in archaeology. Loads of the cave art made in the Stone Age was made by spitting paint onto the walls or putting on with your hands and fingers. So the idea that DNA of the artist could be preserved on the walls in the artwork, that idea has been around for a while. But until now, no one has been able to extract that DNA. So this really is a big discovery. It's got the potential to identify the actual person who did the paintings, those paintings tens of thousands of years ago, and it might also help tell us about the meaning of the artworks.

1:17From New Scientist, this is The World, The Universe and Us. I'm Dr Rowan Hooper. Alison George has been reporting on this for us. Ali, this story is sending shivers down my spine. How have they made the discovery? It's sending shivers down my spine too. It came about through a collaboration called the First Art Project, which is a load of people interested in ancient humans came together and they really wanted to date the art made in the Paleolithic, the Stone Age. And that's something that's also been a challenge for a long time. But there's a really great technique for doing this. What's this substance called calcite forms?

1:56It's a bit like limescale, can form on the walls of caves and over the art. And you can date that using the levels of uranium that's in it. And so you can find out when all these iconic images, such as the beautiful drawings of bison and mammoths and stuff, were made by dating the calcite layer on top of them. But the researchers also thought, well, maybe the DNA becomes trapped in this layer too, or maybe you can even sample the very top of the art. And so that's how this discovery came about through that project. Yeah, so the calcite is kind of like a varnish, natural varnish that goes over the artwork and it might trap this stuff underneath it.

2:39So tell us more about this first art project. What a cool name as well. It's a really cool name. Yeah. So they wanted to go to the caves where the really old art is thought to be. I mean, we don't really know how old this stuff is, but they went to caves where mostly there isn't figurative art with animals and bison and things like that drawn. The really old stuff is thought to be more graphic markings, so red dots and triangles and fingers drawn down in the mud on the cave wall. Or the really cool one is these hand stencils where the people put their hand on the wall and then spat paint over their hands.

3:21So they get a sort of negative stencil. And that's thought to be one of the oldest sort of art motifs ever. So they were sampling this calcite layer over these sort of images and they called in a crack team of geneticists from the Max Planck Institute of Evolutionary Anthropology in Germany. This is an amazing team that have sequenced the Neanderthal genome and the Denisovan genome. So they wanted to get the best geneticists on this project. you know the the hat those handprints uh this is another sending shivers down the spine thing for me isn't it like when you imagine someone maybe you know 30 ,000 years ago put their hand there what they're waving to us from history and now we might be able to get their dna like reaching out literally their hand reaching out through time you said 30 ,000 years ago rowan but the oldest hand stencil in the world is nearly 70 ,000 years old and that's from Indonesia.

4:23I mean, its potential is massive. All right. So what's happened now? What have they found? Okay. So they went to 11 different caves in Portugal and Spain, these first art researchers, and they looked at 24 different panels of art and most didn't contain human DNA to be honest, but one did. They struck gold in a cave called Escoral. I think that's the pronunciation in Portugal, where for the first time they found ancient human DNA on the cave wall. Is it a new technique or they're just getting better at this? Or was it something about that particular cave in Portugal or the pigment that the artists used all that time ago?

5:01So I asked one of the researchers involved in the first art project, Genevieve Bonpettinger, a Canadian art specialist, and here's what she said. honestly it was all of the above it was a convergence based on the last 10 years of you know technique refinement they've been doing combined with the fact that there's certain circumstances in a cave like if pigment gets locked quickly behind calcite which is going to improve the chance of it acting like a little time capsule and then combined of course with luck because the question is will it preserve right now obviously caves are much more likely to preserve than the outside world because they're cooler, stable and enclosed.

5:44And so this was where we had high hopes that caves could actually be a good spot to be able to start finding ancient DNA. And we're hoping that this will now be the first of many now that it's been done. Okay, so Ali, is this the DNA from the person who drew it on the wall? How do we know that? We don't really know. This really is the very tentative first steps in this kind of analysis. it could be from the person who drew on the wall but we really don't know it could be from someone else who touched the wall later or as one of the researchers told me someone sneezed on it later but there is you know the researchers i spoke to were incredibly excited about the potential to one day identify the exact individual who created the art so we have reported in the past that we've got sediment like we've analyzed sediment on the cave floor and found dna from ancient humans in that So how do we know that this art DNA is just kicked up from the sediment or something?

6:46This is actual the artist's DNA. That's a really good question. But there's a really good answer to that question. Because the DNA on the cave floor is kind of a mess. It's human DNA mixed with animal DNA, rabbits, bears, any creature that the people ate or that came in the cave. But the sample they found on the cave wall was exclusively human. So that's very good evidence that it's from direct contact with a human rather than mud being kicked up onto the wall. And another really exciting thing that came out of this Escaral cave in Portugal was the researchers decided to take a control sample from a bit of the wall that had nothing on it.

7:25And to their absolute surprise, that contained human DNA too. probably when someone maybe touched the wall or leant against it or sneezed on it or something. And this means that caves have the potential to be an absolute treasure trove of information about the ancient humans who went into them, even when there are no artefacts. There's no art, there's no evidence of fire on the floor or whatever. One of the researchers I spoke to, Hippolito Colaldo Giraldo, who's a Spanish archaeologist, said it's as though the cave walls have become the pages of a blank book that we will be able to fill with new discoveries bit by bit.

8:04Wow. God, and that is mind-blowing, isn't it? Because there must be so many caves that people have been in over the millennium and suddenly the potential of finding out more about our ancestors is just really exploding, isn't it? Yeah. So what do we know so far about DNA profiling that we've been able to do on the DNA from the cave wall? Yeah, as far as I understand it, the DNA is quite degraded and you get these tiny, tiny amounts. But even then, they've managed to work out that three of the samples they got from the walls were predominantly from women. The fourth was male. So women were dominating in the sampling.

8:43and the genetic profile most closely matched to a population that lived, say, around 15 ,000 years ago called the Western hunter-gatherers. So this DNA is likely to be tens of thousands of years old. And one day we'll be able to find a lot more information about these people, like, for example, their hair colour, their eye colour, who they interbred with. The treasure trove is potential. It's amazing. Yeah. Are they as excited as us? Are they just hopping about this? Yeah, yeah. And the superlatives that came from the people I spoke to, they were sort of astonished, amazed. You know, they really are.

9:21This is very early days, but the potential is huge. Well, there is just the start, right? As you say, there is loads more. There's going to be loads more to come on this. Yeah, the really, really exciting thing is that the First Art team actually this month carried out a really extensive sampling in Spain of really interesting caves, including caves called Neha and Ardales, which have got a very, very old artifact in them, which look like they predate any modern humans coming to Europe. So the art in them, we're talking sort of red dots and red smears and things like that, has been attributed to Neanderthals very controversially.

10:01So we may finally be able to answer the question about whether Neanderthals were painting on cave walls. Is that controversial? I kind of thought that there was Neanderthal art or markings. Yeah, well, I think a lot of people think that Neanderthals are perfectly capable of doing art, but actually pinning it down and saying this is definitely Neanderthal, it all comes down to the dating. And, you know, there's always wriggle room there. So we could, with this technique of DNA, might really be able to pin this down. Wow, Neanderthal artwork. and also you mentioned Indonesia so this could go this could open up other species Denisovans and other things that are happening in Indonesia and other parts of the world.

10:48Yeah so there's researchers at the moment analysing the calcite of the oldest cave art we know of in the world that's in Indonesia and they're trying to get you know DNA from the calcite that forms over the art there and it's a lot warmer and more humid there so the likelihood is that the DNA may have degraded uh also it's potentially a lot older as well but still you know the potential is huge so maybe all this lovely amazing artwork there some of it maybe is made by denisovans not not our species yeah um and i saw some of the pictures of the researchers and they are all gloved up and masked up like like we're familiar from you know csi crime shows and that and is that how they have to work now yeah because if you're going to be trying to find ancient dna i mean one of the researchers said to me it's like finding a needle in a haystack of all the chemicals that are there and then if you've got modern human contamination too if you're breathing on this stuff um you're gonna make she said you're gonna make that haystack an awful lot bigger if your dna goes into the mix too so yeah you've got to treat these um sites as as like a forensic uh investigation and study and play come together on a windows 11 pc and for a limited time college students get The best of both worlds.

12:09Get the Unreal College deal. Everything you need to study and play with select Windows 11 PCs. Eligible students get a year of Microsoft 365 Premium and a year of Xbox Game Pass Ultimate with a custom color Xbox wireless controller. Learn more at windows.com slash student offer. While supplies last, ends June 30th. Terms at aka.ms slash college PC. Okay, look, let's talk about the meaning of it because this is something that I don't know how much we'll be able to say, But if we start to learn who made this art, and you've already mentioned that, you know, there were groups of maybe groups of women there.

12:42What might that tell us about what it means, what the art was for? Well, you could potentially get a huge amount of information about the art from the DNA that's found on it. For example, if you know that a group was visiting a cave, but only one person, say an older woman or a younger man, was making the artwork. or it was only men who drew the lions or the women who drew the red triangles, you can start building up a picture of how this art might have had meaning to the people who did it or if hand stencils were only women or, you know, that kind of thing. Yeah, I think this is extraordinary.

13:21One of my favourite stories, Ali, from recent times is a story you did a few years ago about the Lascaux art in France. So this is the really famous ones with the wonderful bison. Is it bison? But mammoths, horses, aurochs on the walls. Beautiful artwork. And there are these dots and little like symbols on some of the animals. And many people just ignore them because you're sort of mesmerized by the beauty of the animals. But then one researcher started looking at what would these symbols mean? And they started to correlate with the reproductive information about the animals. So, you know, three dots might mean this is how many offspring this particular species has or when it reproduces in the year.

14:07So it's ecological document from tens of thousands of years ago. That's incredible. So we might be able to start fighting about meaning like that. Yeah, yeah, they think that these sort of graphic symbols that are drawn with animals, like dots and lines and Y symbols, might be recording the sort of mating habits of these animals, which were so crucial to these people. They were living off these animals and they were really connected to them. And, you know, that is another really interesting area. What do all these graphic symbols mean? I mean, I went to a cave with Genevieve von Pettiger, who featured earlier in northern Spain.

14:47and there were these upside down, rows of upside down triangles drawn on the wall. And you just looked at them and you thought, my God, that's got to have incredible meaning. But what on earth do they mean? It was such complex sort of information on the walls and it was just mind-blowing. What did she think they mean? No one knows yet. No one knows. But I suppose if you know when they were made and you can look at trends from different caves and you can look at what groups were using which symbols, You can start to build up a picture and are the triangles ever only used with certain animals? And you can start building up a picture of the meaning, but maybe we'll never know what it means.

15:24Well, this is certainly giving us a better insight into it than we've ever had before. So I can't wait to find out what, you know, to follow this story on as we start to get more DNA about and understand these artists, what they were doing. What a story. We'll leave it there. Thanks, Alison George. Thanks to you for listening and do follow and subscribe wherever you get your podcasts. Bye for now. Bye.