Andrew Collins exclusively reveals the true face of a Siberian Denisovan.

What the Denisovans might have looked like has been one of the hottest debates in paleoanthropology since the discovery of this extinct human lineage back in 2010. Were they big or small? Did they look like their cousins, the Neanderthals, or were they more like anatomically modern humans in appearance? Lastly, were they the giants of legend as some are now speculating ?

Resolving these issues is difficult as just a handful of Denisovan fossil remains have been found. They include two enormous molars, two fragments of a parietal bone from a Denisovan skull, and a finger bone from a young female who lived 75,000 years ago - all found during excavations at the famous Denisova Cave in Siberia. There is also a 160,000-year-old mandible that was found in a cave on the edge of the Tibetan plateau in northwestern China and recently identified as being that of a Denisovan.

Despite this frustrating situation, in September 2019, it was announced that Professor Liran Carmel and Dr. David Gokhman of Hebrew University, Jerusalem, had used epigenetics to analyze gene regulation and cytosine degradation in order to determine the suspected physical make up of the Denisovan face. Their finished reconstruction shows the head and neck of a young female with a rounded head, wide mouth and jaw, minimal chin, brown skin, and striking brown eyes. So well received was their reconstruction that in December 2019 the team won the 2019 Science magazines Peoples Choice for Breakthrough of the Year .

The Hebrew University teams award-winning reconstruction of the Denisovan face. (Image: Maayan-Harel)

Crucial in Carmel and Gokhmans reconstruction of the Denisovan face was data gained from the lineages genome first sequenced in 2010 by the Max Planck Institute in Leipzig, Germany. This showed that a significant number of Denisovan genes have been inherited by modern human groups through interbreeding in the distant past. It is perhaps for this reason that Carmel and Gokhmans Denisovan bears similarities to Papua New Guineans and also to certain Australian Originals, both of whom display anything up to 5 percent Denisovan DNA ancestry, the highest rate in any human groups. (See, for comparison, figure below which shows Koori Originals photographed around 1847 in Victoria, Australia. Their features, particularly the man in the middle, can easily be compared with Carmel and Gokhmans Denisovan reconstruction).

Koori Originals photographed by Douglas T. Kilburn around 1847 in Victoria, Australia. Their features are comparable with those of Carmel and Gokhmans Denisovan reconstruction. (Image: National Gallery of Victiria / Public Domain )

So did all Denisovans look like Australian Originals, or indigenous Melanesians? The answer is almost certainly no. For example, studies of Denisovan genes inherited by modern populations in East Asia, Island Southeast Asia, and Papua New Guinea have revealed new information about the evolution of the Denisovan genome. This shows that soon after the Denisovans split from a common ancestor they shared with their cousins the Neanderthals (as much as 475,000-450,000 years ago) the population diverged into two separate types.

One Denisovan population came to inhabit a vast territory possibly extending from Central Asia, Siberia, and northern China in the north to Mongolia and Tibet in the south. Their descendants most likely moved through the Russian Far East before finally crossing the Beringia land bridge into North America; this occurring perhaps as early as 20,000 years ago. From the many discoveries being made in the Denisovan layer at the Denisova Cave it would seem that these Siberian Denisovans as they are known displayed a high level of advanced human behavior.

This included the creation of beautiful jewelry (see, for instance, the Denisovan bracelet below), the making of the earliest known musical instrument in the form of a whistle or flute, the earliest manufacture of bone needles, used most probably to create warm winter clothing, and the production of the earliest symbolic art. This takes the form of an exquisite carving of a mountain lion, possibly a childs comfort toy, which has incised markings suggestive of a basic knowledge of cyclic time.

Denisovan bracelet found in the Denisova Cave, Siberia, and thought to be at least 50,000 years old. (Siberian Times)

It is also thought possible that the Siberian Denisovans developed a sophisticated blade tool technology that was afterwards adopted by the first modern humans to settle in Mongolia some 30,000-40,000 years ago.

The other population of Denisovans lived in southern and southeastern Eurasia, as well as in Island Southeast Asia, Melanesia and possibly even Australia. They displayed a more basic genome, suggesting that they were a more archaic lineage than their northern neighbors.

This second branch of Denisovans are known as Sunda Denisovans (occasionally Australo-Denisovans) after the former Sunda landmass that once linked the Malaysian Peninsula with Indonesia. They themselves would appear to have split into two distinct groups, the youngest of them, according to genetic evidence, perhaps lingering on in places like the Philippines and Papua New Guinea until around 15,000 years ago.

So far there is no hard evidence that the Sunda Denisovans developed the same advanced human behavior achieved by their northerly neighbors. Stone tools as much as 50,000 years old found on the Indonesian island of Sulawesi may have been made by Denisovans. If they were created by Denisovans then it would imply that their ancestors had not only crossed the Wallace Line, the deep water channel dividing most of the Indonesian archipelago from Sulawesi, but also that they had sea-going capabilities.

This said, the Sunda Denisovans are unlikely to have developed a sophisticated blade tool technology like their northerly counterparts, since only so-called flake tools existed in Island Southeast Asia during the prehistoric age.

If the portrait of the young female created by Carmel and Gokhmans Hebrew University team is truly representative of a Denisovan, then it is the likeness of a Sunda Denisovan, not a Siberian Denisovan, whose evolutionary development was quite different to that of its southerly counterparts.

So the question remains: what did the Siberian Denisovans look like? How different would they have been to Carmel and Gokhmans reconstruction? To answer this question the present writer asked independent researcher and writer Debbie Cartwright to help in the collation of everything available on the physical appearance of a Siberian Denisovan.

This included all obvious information obtained from the Denisovan genome, such as the fact that Denisovans had brown hair, brown eyes, and brown skin, along with any further information to be gleaned from the few fossil remains found to date. We also looked at the suspected effects on the lineages evolutionary development derived from knowledge that the Siberian Denisovans would appear to have thrived at very high altitudes and also in extremely cold conditions. This probably included the Altai Mountains of Siberia and Mongolia and the Tibetan plateau, one of the highest places on earth.

Such extreme environments might well have necessitated the development of specialized respiratory systems including highly adapted noses that were able both to absorb all available oxygen at altitudes where the air was particularly thin, while at the same time warming up the air sufficiently before it passed into the lungs. For instance, a study by Mark Shriver, a geneticist and anthropologist at Pennsylvania State University, found that the effects of climate upon the evolution of nose size and shape suggested that larger, narrower noses are more suited to higher and colder climates, while wider flatter noses are more suited to hot tropical climates.

It is important also not to forget that Denisovans were related genetically to Neanderthals, meaning that they would have borne at least some physical characteristics in common with them. This probably included a heavy brow bridge, thickset features, and a receding chin - a fact confirmed with the discovery of the 160,000-year-old Denisovan mandible found in a cave on the Tibetan plateau in northwestern China. This is extremely wide and robust and lacks a well-defined chin.

The Xiahe mandible, only represented by its right half, was found in 1980 in Baishiya Karst Cave. ( Dongju Zhang, Lanzhou University )

Also, like the Neanderthals, the Denisovans probably had receding foreheads and extended occipital buns, meaning they perhaps had long heads, as opposed to the more rounded craniums displayed by some early modern human populations such as Australian Originals.

Having made the connection between Denisovans and Neanderthal physiology it is also likely that Denisovans had at least some traits in common with anatomically modern humans ( Homo sapiens ). When a previously misplaced fragment of the finger bone found in the Denisova Cave in 2008 was reunited with the second, more famous, fragment used by the Max Planck Institute to sequence the Denisovan genome, it was realized that the finger did not resemble that of a Neanderthal as had been widely expected. Although the finger bones of archaic humans such as Neanderthals and Homo erectus are extremely thick and quite stubby, the Denisovan finger bone is a lot slimmer, like that of an anatomically modern human.

This connection between anatomically modern humans and Denisovans is perhaps far deeper than anyone has so far suspected for, as the current writer has speculated elsewhere, there is a strong likelihood that the ancestors of the Siberian Denisovans, after leaving Africa, encountered pre-dispersal modern humans already occupying the Levant. Evidence for the existence of these early modern humans has come from the discovery at the Qesem Cave in Israel of eight teeth belonging to members of the Acheulo-Yabrudian Cultural Complex (AYCC), which thrived in the Levant corridor circa 420,000-250,000 years ago. These were found to be almost identical to those of anatomically modern humans.

Having interbred with these early modern humans, the Siberian Denisovans would then have continued their migration eastwards, entering Central Asia, Siberia, and finally, Mongolia and China. If correct, they would have been carrying physiological traits picked up from early modern humans living in the Levant. This is something that the Sunda Denisovans would seem to have missed out on since they most likely took a different route out of Africa, crossing the Arabian peninsula before entering southern Asia, southeastern Asia, and, finally, Island Southeast Asia.

The possibility that the Siberian Denisovans were carrying at least some early modern human genes might also help explain why the Siberian Denisovan genome is slightly different to that of the Sunda Denisovans, and why they would appear to have displayed advanced human behavior before their final disappearance around 45,000 years ago.

And so this brings us to an impression of the Siberian Densovan that appears as follows

The face of a Siberian Denisovan by artist George Hernandez working in concert with writer-researcher Debbie Cartwright and the present author. Genetic information, Denisovan and Neanderthal fossils, and unique traits in anatomically modern humans were used to reconstruct this likeness. (Picture credit: Hernandez/Cartwright/Collins)

For our reconstruction of the Siberian Denisovan we have included some physical traits seen in modern human populations that perhaps benefitted from introgression with this archaic human population. They include modern populations in North Asia, East Asia, and even North America - where First Peoples of the Great Lakes-St Lawrence River region such as the Ojibwa and Cree have been found to possess some Denisovan DNA. They, more than any other population, might well have retained Siberian Denisovan traits through the isolation of their ancestors prior to first contact with Europeans at the start of the historical period.

Debbie Cartwright and I then worked with talented Californian artist George Hernandez to achieve the best likeness of an archaic Siberian Denisovan, here revealed for the first time. It is shown also for comparison alongside Carmel and Gokhmans own reconstruction.

The reconstructed face of a Siberian Denisovan (left) alongside the Hebrew Universitys own representation of a Sunda Denisovan (right). (Picture credits: Left, Hernandez/Cartwright/Collins; Right, Maayan-Harel)

Many similarities can be noted between the two versions, including wide mouths, receding chins, heavy brow ridges, brown eyes, skin and hair, and also large noses, but there are also some differences as well. The face of the Siberian Denisovan is much longer, the brow ridge more prominent (like that of a Neanderthal), the forehead recedes more, while the cheekbone is much higher.

We have also chosen to give the Denisovan a narrow, aquiline nose with a prominent bridge, as opposed to the large, but much flatter nose, of the Carmel and Gokhman reconstruction. As we have seen, such distinctive noses helped in the absorption of oxygen in elevated environments where the air is particularly thin. Yet curiously, an aquiline nose (also known as the Roman or hooked nose) combined with a prominent bridge has often been compared with the head shape of a large bird, most obviously that of an eagle (the Latin word aquiline means eagle-like).

Bird shamanism would appear to have played a significant role in human development for as much as 400,000 years. If, as we suspect, the Siberians Denisovans did possess aquiline noses, then with their prominent bridges and heavy brow ridges there is every reason to suspect that their facial details could be said to resemble those of a bird, something noted in individuals with aquiline noses in more modern times.

Illustration comparing an individual with an aquiline nose, heavy brow and prominent nose arch with the head of an eagle by Charles Le Brun (Image: CC BY 4.0 ).

If correct, then this might have encouraged Siberian Denisovan groups to adopt the guise of birds to engage in early forms of animism and even shamanism, similar to that noted in connection with the AYCC inhabitants of the Qesem Cave in Israel as much as 400,000-250,000 years ago. In other words, Siberian Denisovans came to resemble birds both in physical appearance and in mannerisms, a connection emphasized and even celebrated through ritual practices.

Lastly, we chose to give our Denisovan thick, dreadlocked hair as opposed to the frizzy hair seen in Carmel and Gokhmans reconstruction. Why did we do this? The answer is two-fold. First, it comes from the adoption of dreaded hair for socio-cultural and socio-religious purposes by various modern human populations such as the Himba people of Namibia, the Hindu Sadhus or holy men of India, and the Rastafarians of Jamaica.

Secondly, the deliberate management of long thick hair by dreading and the subsequent use of mud (as well as goat hair in the case of Himba women) to help coat it aids in the prevention of lice and other insect infestations. In addition to this, dreadlocks bunched up on the head would have accentuated the Denisovans suspected elongated heads, emphasizing their individual identity in a world that towards the end of their time circa 45,000-50,000 years ago, would have included Neanderthals, anatomically modern humans and, most likely, hybrids stemming from an admixture of all these various lineages of the homo genus.

Clearly, such a unique feature is based on speculation of how the Siberian Denisovans managed long hair without cutting it and how it might have come to signify their ritual culture. This is an important point, for no matter what evidence is used to reconstruct the face of an archaic human, it will always involve some personal bias. This can be seen, for example, from the many different representations of Neanderthals. They range from virtual ape-men covered in thick body hair, to others where the individual becomes almost indistinguishable from any red-haired, freckled person you might encounter on the street today.

Thus, it has to be accepted that the Denisovan face imagined by artist George Hernandez under the directions of Cartwright and the author must by definition have its own personal bias. This said, we feel it is the closest representation to date of a Siberian Denisovan, as opposed to the face of the Sunda Denisovan developed by Carmel and Gokhman.

Further assessments on the shape of the Denisovan skull and the proportions of the face can only be achieved following the discovery of additional fossils; most urgently a complete cranium. Beyond this will be the eventual discovery of a Denisovan femur, which will help settle the debate over whether or not the Denisovans were of exceptional size and height.

This was first implied by the enormous size of the two Denisovan molars found in the Denisova Cave. Although the two fragments of the Denisovan skull found at the site in 2016 are also suggestive of a large body frame, not enough fossil remains have come to light to answer the question of height and girth with any degree of certainty. So, until such times we must be content with the two faces of a Denisovan presented to the public so far that of Carmel and Gokhmans team from the Hebrew University and that of our own. At least these provide some idea of what this extinct branch of the Homo genus might have looked like.

Top image: The reconstructed face of a Siberian Denisovan (right) alongside the Hebrew Universitys own representation of a Sunda Denisovan (left). Source: Left Hernandez/Cartwright/Collins; b) Maayan-Harel)

By Andrew Collins

Andrew Collins is a history and science writer. His most recent book is Denisovan Origins, co-authored with Gregory L. Little (Bear & Co, 2019).

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Two Faces of a Denisovan Revealed and Explained - Ancient Origins