At issue is who made items such as a stunning bracelet of green-hued chlorite, bead jewellery comprising ostrich eggs, and a needle - still useable today - pictured here. Picture: IAET SB RAS

Two new scientific studies have led to a questioning of the theory espoused in recent years by Russian and foreign experts familiar with Denisova cave in the Altai Mountains that a remarkable collection of jewellery and artefacts unearthed here were the creations of neither Homo sapiens nor Neanderthals.

There is no dispute as to the existence of a distinct but long extinct early human species known as the Denisovans.

The two new studies in Nature accept that this grouping occupied the limestone cave from around 287,000 to 55,000 years ago, sharing it for some of this period with Neanderthals (193,000 to 97,000 years ago, so predating the time when these exciting artefacts were made).

‘Our results also imply that all known Neanderthal and Denisovan fossils pre-date the appearance of the Initial Upper Palaeolithic (45,000–48,000 years ago) and the directly dated personal ornaments and bone points.’

Yet a new timeline for the early human occupation of the cave, and of the age of the remarkable ancient items found here, has raised scientific questions which were aired recently in publications around the world.

At issue is who made items such as a stunning bracelet of green-hued chlorite, bead jewellery comprising ostrich eggs, and a needle - still useable today - pictured here.

'The radiocarbon ages for the oldest pendants and the bone points at Denisova Cave overlap with the directly dated anatomically modern human femur from Ust’-Ishim in western Siberia12 (43,200–46,880 cal. years),’ stated one of the studies.

‘This raises the possibility of a connection between the spread of modern humans and the emergence of innovative behaviours and symbolic artefacts across northern Eurasia at the start of the Initial Upper Palaeolithic, by 43,000–48,000 cal. years.'

The distance between Denisova Cave and Ust'-Ishim.

In other words, although no Homo sapiens presence has been detected in Denisova cave - or anywhere near it - from a period so long ago, evidence of modern humans some 1,600 kilometres (994 miles) away, at Ust’-Ishim, does exist.

‘Our results also imply that all known Neanderthal and Denisovan fossils pre-date the appearance of the Initial Upper Palaeolithic (45,000–48,000 years ago) and the directly dated personal ornaments and bone points,’ the research stated.

Yet the jewellery and artefacts can be dated to a time ‘synchronous’ with Homo sapiens being in western Siberia, albeit nowhere near Altai.

Crucially, the authors argue that this ‘raises the possibility that modern humans may have been involved in the manufacture of these artefacts’.

Ivory tiara found in the Denisova Cave in summer 2018.

The article - 'Age estimates for hominin fossils and the onset of the Upper Palaeolithic at Denisova Cave' published in Nature - goes on to say ‘it is parsimonious at present to suggest that the makers of these artefacts may have been Denisovans.

‘Future discovery of fossils from this site and others, and determination of their ages and genomes using a combination of methods, will shed further light on the relationships between archaic and modern humans and their associated material cultures.’

The conclusions speak of a doubting that the enigmatic Denisovans - whose genes live on in the native populations of Papua New Guinea and Australia - made these stunning finds.

World oldest stone bracelet found in 11th layer of Denisova cave.

Paleoanthropologist Chris Stringer, of the Natural History Museum in London and not a member of the team, seized on the scepticism that Denisovans manufactured the jewellery and other items.

'My money would be on early modern humans, who can be mapped elsewhere at this date, for example at Ust'-Ishim in Siberia,’ he was quoted as saying to sciencemag.org

‘Only more discoveries and more research can resolve that question.’

He told Live Science ‘the authors of the [radiocarbon dating] paper rather surprisingly argue that it's most parsimonious to assume that Denisovans were responsible, even though no Denisovans are yet known as late as that in the sequence’.

Professor Shunkov, head of the Institute of Archaeology and Ethnography in Novosibirsk, and a named author of the 'Age estimates for hominin fossils and the onset of the Upper Palaeolithic at Denisova Cave' paper, acknowledged that the new chronology from more detailed dating of the human presence in the cave ‘opens up new spaces for different interpretations’, yet he remains convinced that the Denisovans were there.

Ust'-Ishim bone. Irtysh river bank where the bone was found in 2008. Pictures: Antropogenez

He told The Siberian Times: 'The beginning of the Upper Palaeolithic has traditionally always been associated with the appearance on the evolutionary arena of Homo sapiens.

‘But in those layers of Denisova Cave, where we initially recorded the signs of the Upper Palaeolithic, first of all, these were bone artefacts and various decorations from gemstone.

‘The most ancient layer of this period is 11.2. of the cave’s Eastern Chamber, and these objects are fixed together with the anthropological remains of Denisovan.

’It was formed between 60,000 and 50,000 years ago. In other parts of the cave this layer is under 50,000 years.

‘That is, we can say that the Upper Palaeolithic was formed in Denisova Cave around 50,000 years ago.’

So, he stressed: ‘If worldwide this period is associated with Homo sapiens, in our case it was Denisovan.’

He said: ‘The first bone tools and ornaments in Denisova Cave we associate with the activities of Denisovans.

‘And not everybody is ready to accept this. We do not associate this with Homo Sapiens.’

Bone needle found in the Denisova Cave in 2016.

Yet ‘we are confident because we see the gradual evolution.

‘We record his presence throughout the second half of the Middle Pleistocene and the first half of the Upper Pleistocene.

‘From layers 22 to 11 we see the gradual development of Denisovan industry.

'We received the most prolonged, relatively uninterrupted chronology of the existence of primitive man in the south of Siberia.

‘And we can confidently say that the culture of the Upper Palaeolithic was formed in Denisova Cave about 50,000 years ago, because in these layers we found the most ancient finds of objects of art and utilitarian tools made of bone and tusk.

‘These are the most ancient dates of the beginning of the Upper Palaeolithic in world archeology, and they are associated with the presence of the Denisovans.

‘The uniqueness of this phenomenon lies in its continuity, in contrast, for example, to European ancient history, where Homo sapiens came to replace Neanderthals with Mousterian industry with their own cultural innovations.

‘The remains of Homo sapiens in the Pleistocene sediments of the Palaeolithic sites of Altai have not yet been discovered.

‘We see that in the territory of southern Siberia, Palaeolithic cultural traditions developed on an autochthonous basis, which was confirmed by both archaeological, and anthropological and palaeogenetic studies.’

Finger bone fragment of 'X woman', a juvenile female, found in Denisova cave in 2008. Fragment of the bone of Denny - an inter-species love child. Picture: Max Planck Institute

The new radiocarbon dates obtained from some of the pendants and bone tools put them at 43,000 to 49,000 years old, a period in which there are no so-far-discovered hominin remains.

The youngest Denisovan specimen dates to between 52,000 and 76,000 years ago.

‘Our Russian colleagues have rightfully argued that we have no modern human fossils at Denisova and no modern human DNA from Denisova sediments, so why invoke modern humans?’ asked Katerina Douka of the Max Planck Institute for the Science of Human History in Germany.

Professor Tom Higham, of the University of Oxford in the UK, who with Douka was involved in dating the artefacts, said: ‘One might say that given [the Ust’ Ishim fossil], we should assume modern humans made the pendants and bone tools at Denisova, but we don’t have modern human fossils in the Altai at that time….

‘It could be modern humans but the most parsimonious explanation for the moment is that it’s Denisovans’.

Beads made of ostrich eggs shell.

Douka and Higham and their colleagues used radiocarbon dating to ascertain the ages of artefacts - but this is viable only up to around 50,000 years ago. The ages of human fossils compared their DNA sequences with those obtained from other human fossils, converting ancient DNA differences to time, using a statistical model to calculate the most probable ages.

Separately, Zenobia Jacobs and Bo Li of the University of Wollongong in Australia, used optically stimulated luminescence to date sediments from the cave.

They also reconstructed the environmental conditions at the site between 300,000 and 20,000 years ago.

The Denisovan branch of ancient man was first identified a decade ago when a tiny finger bone fragment of so-called 'X woman' was discovered in this cave.

She was found to be neither Homo sapiens nor Neanderthal.

Researches work inside the Denisova cave, views from outside and inside the Denisova Cave.

Last year details were revealed in Nature journal of the discovery of a fragment of bone belonging to an inter-species love child called Denny who lived some 90,000 years ago.

She was the product of a sexual liaison between a Neanderthal mother and a Denisovan father, according to DNA findings.

The Institute of Archaeology and Ethnography is part of the Siberian Branch of the Russian Academy of Sciences.



The full list of the authors of 'Age estimates for hominin fossils and the onset of the Upper Palaeolithic at Denisova Cave' are:

Katerina Douka, Viviane Slon, Zenobia Jacobs, Christopher Bronk Ramsey, Michael (Mikhail) V. Shunkov, Anatoly P. Derevianko, Fabrizio Mafessoni, Maxim B. Kozlikin, Bo Li, Rainer Grün, Daniel Comeskey, Thibaut Devièse, Samantha Brown, Bence Viola, Leslie Kinsley, Michael Buckley, Matthias Meyer, Richard G. Roberts, Svante Pääbo, Janet Kelso & Tom Higham.