A treasure trove of new Denisova discoveries revealed at a recent anthropological conference

The annual meeting of the American Association of Physical Anthropologists, which was held in late March in Cleveland (Ohio), was eagerly awaited by people interested in human origins, as it would be here that Bence Viola, a Canadian paleoanthropologist at the University of Toronto, would reveal details of the discovery of the first fragment of Denisovan's skull.

In fact, seven major presentations offered new insights into the enigmatic world of the Denisovans, whose existence was confirmed for the first time when a finger discovered in Denisova's cave in Siberia was determined to belong to an unknown type of archaic man.

Subsequent genetic studies have revealed that a number of current populations from southern and eastern Eurasia, as well as from Australia, Melanesia and the United States, have been found to be present. Oceania, have up to 3-5% ancestry derived from Denisovans, which testifies to their extensive distribution before birth. supposed to disappear about 45,000 to 40,000 years ago.

The skull fragment of Denisovan

Bence's presentation on Denisovan's skull, discovered during excavations carried out in the Denisova Cave in Siberia in 2016, is a piece of the size of a palm belonging to the left-back part of the cerebral cage. Apparently, the skull is extremely thick, like the one previously observed in other archaic humans, most obviously Homo erectus.

The cave of Denisova, in Siberia, where the discovery of a skull fragment of Denisovan has now been confirmed. (Демин Алексей Барнаул / CC BY SA 4.0 )

A study of the mitochondrial DNA of the skull fragment, inherited from mother to child, has already confirmed its belonging to that of a Denisovan, belonging to the population known today as the Denisovans of Siberia (see below). -Dessous). Its sheer thickness has led Svante Pääbo of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, to lead the team that has successfully extracted Denisovan's bone genome, The Guardian newspaper that, "They [the Denisovans] seem to have been very tall and sturdy, even compared to Neanderthals, "adding that by their size and appearance," they were probably quite impressive. "

Until now, no image of the skull fragment has been found in the public domain, but expect an official artistic reconstruction of what a Denisovan might have looked like in due time.

Drawing of a Neanderthal mother and father Denisovan with their child, a girl, at Denisova Cave in Russia. ( Credit: Petra Korlević )

Proof of three types of Denisovans

In another presentation by Murray Cox, population biologist from Massey University in Palmerston North, New Zealand, and molecular biologist Herawati Sudoyo of the Eijkman Institute of Molecular Biology in Jakarta, a new study on the complete genome DNA of 161 people was revealed. groups in Indonesia and Papua New Guinea show that their oldest ancestors met a local population of Denisovans just 43,000 years ago. Moreover, it is from them that these modern human groups inherited about 400 genes, including a variant of the immune gene (TNFAIP3) and a gene involved in the diet (WDFY2).

What is more significant is that it is also clear that some of these modern populations, especially those of Papua New Guinea, are mixed with another much later group of Denisovans. They possess genes slightly different from those of the previous group of Denisovans, which means that there could well have been three different types of Denisovans at a time.

Type 1, generally called Denisovans of Siberia, whose remains were found in the cave of Denisova and whose genes are flourishing today in the modern populations of East Asia and North America, is now designated as type D0, the two groups having prospered Southeast Asia Island, including Papua New Guinea, designated D1 and D2. What is even more incredible is that one of these groups (D1) could very well have survived until 30,000 to 15,000 years ago, the presumed timing of their introgression with the modern humans of this region .

Excavation work in the room is from the cave of Denisova, Russia. ( Credit: Bence Viola, Max Planck Institute for Evolutionary Anthropology )

This new knowledge on the Denisovans of South-East Asia, also called Australo-Denisovans or Sunda Denisovans, confirms the evidence presented in a genetic study published in 2018. This led to the conclusion that the Denisovans genome of the Southeast Asian island seemed so different from that of the Siberian Denisovans, it is clear that the two populations separated from a common Denisovan ancestor 363,000 years ago, the Denisovans themselves being separated from their brother group. Neanderthals, between 380,000 and 470,000 years ago.

In turn, they separated from a common ancestor shared with modern humans ( Homo sapiens ) between 770,000 and 550,000 years ago. This means that the two basic types of Denisovans, one in Siberia (and presumably on the Tibetan Plateau) and the other in Southeast Asia, Australia and Oceania, should perhaps to be classified in very distinct archaic populations, each with its own name.

The spread and evolution of Denisovans based on evidence available in 2014. (John D. Croft / CC BY SA 3.0 )

Mating and mixing Denisovan's DNA

It is, however, more important to confirm whether a branch of the Denisovans of Southeast Asia survived up to 30,000 to 15,000 years, as proposed by Cox and Sudoyo in their study. This is a controversial claim, judged unlikely by Cosimo Posth of the Max Planck Institute for the Science of Human History in Jena, Germany.

According to him, the evidence suggests a late union with individuals of high Denisovan genes, which might reflect a meeting between a relatively isolated modern population of Denisovan hybrids and distant modern human societies. For him, modern humans united with Denisovans, after which modern populations diverged, allowing each branch to retain a different set of Denisovan genes. Some time later, apparently between 30,000 and 15,000 years old, if Cox and Sudoyo are right, modern human societies reconnected, creating a new DNA mix of Denisovan.

However, if some of Denisovan's groups from Southeast Asia survived until 15,000 years ago, it means that they may well be the last remaining archaic human population to coexist with humans. modern, beating the Neanderthals of about 25,000 years. Homo erectus approximately 10,000 years. They survived in small groups in Java until about 25,000 years ago.

Reconstruction of an adult Neanderthal man, based on the skull of La Chappelle-aux-Saints, dated c. 50,000 years ago, by E. Daynes (2010), Museum of Human Evolution, Burgos. ( CC BY SA 4.0 )

The biggest question now is the impact of Siberian Denisovans and their sister groups in South-East Asia insular on the emergence of modern human societies, and the transfer of technologies, cosmologies, artistic skills and even rudiments of civilization.

All of these topics are explored in the new book Denisovan Origins: Göbekli Tepe, The Hybrid Human and the Genesis of the Giants of Ancient America, written by Dr. Greg Little and myself and published in September by Inner Traditions.

We show how the Siberian Denisovans had a considerable impact on the spread of Upper Palaeolithic traditions and, through it, on the development of civilization, south and east of Siberia, as well as on the west. to the Atlantic coast of Europe. perhaps even beyond that in the Americas. This is important because it is only from the Siberian Denisova cave that we have irrefutable evidence not only of their presence, but also, apparently, of their immense sophistication, as evidenced by archaeological discoveries such as the extraordinary Denisovan bracelet. at least two bone needles, involving the manufacture of tailored clothing; as well as whistle and flute fragments, suggesting the invention of music and the presence of an extremely advanced blade tool technology that would inspire the standard toolkit of modern man to the Neolithic.

What is less clear, however, is the impact of the insular Southeast Asian Denisovans on the emergence of modern human societies in this region. Some might turn to the megalithic megalithic hill of Gudung Padang in Java, Indonesia, which would now be 25,000 years old, as well as on the rocky platform of Yonaguni, the most westerly island in the world. Japan, which has been submerged for at least 10,000 years. years, as evidence of the earlier presence in Southeast Asia of advanced groups of Denisovan.

In addition to that, we have painted rock art on the Indonesian island of Sulawesi dating back at least 40,000 years ago. Evidence also from the Ryukyus, Australia and Remote Oceania suggest the presence of important navigation technologies 35,000 years ago. All of these places support modern populations displaying up to 5% Denisovan ancestry. This alone indicates the anterior presence in the region of Denisovans or their hybrid offspring.

Bradshaw Rock Art

The earliest known representations of high seas vessels from this region come from the 20,000-year-old Bradshaw Rock Art Site, located in Kimberley, in northwestern Australia. Considered to be at least 20,000 years old and probably as much as 50,000 years old, an example shows a boat with turned-up ends and a rectangular rudder (see figure 1 below). Horizontal streaks can be distinguished along the hull, suggesting a fiber construction. No less than 20 human figures are seen inside the boat, confirming its enormous size. Very clearly, the high bow of the ship is designed to cut large waves on the high seas. Another example of ocean vessel seen nearby shows up to 29 people inside its hull.

Fig. 1. 20,000-year-old oceanic vessel belonging to the Bradshaw Rock Art Collection, Kimberly, Western Australia (after Grahame L. Walsh). No less than 20 human figures are visible in its hull (Image: © Andrew Collins).

In addition to the representations of the canoe and the bow-boat at the Bradshaw rock art site, there is a whole series of painted murals depicting characters depicting men dressed in elaborate costumes and huge headdresses. Others stand next to abstract anthropomorphs of a huge size.

Among the works of art are highly stylized characters who seem to float beside or turn into animals, above which are celestial objects or manifestations of another world (see Fig. 2) . The immense sophistication of Bradshaw's rock art is undeniable and knowing that it is 50,000 years old is an extraordinary achievement.

Rock art from the Bradshaw Collection of Western Australia depicting human figures seen next to a kangaroo-like creature with celestial objects or manifestations of another world overhead. ;them. ( Public domain )

Is it possible that Denisovans or so-called Denisovan-modern human hybrids in Southeast Asia, Australia and Oceania have been at the origin of the sudden emergence of advanced human behavior? , including the invention of ocean-going vessels, perhaps 50,000 years ago? Or were these technologies simply the product of the first modern humans who could reach the region from Africa, probably 75,000 years ago?

Until we can absolutely confirm the physical presence of Denisovans or Denisovan-modern human hybrids pronounced in insular Southeast Asia, Australia and Oceania, it is unlikely that the present day. we can answer these extraordinary questions with some degree of certainty.

Top image: Man walking in a marine cave at sunset, illustration, painting. A new study on Denisovans helps to better understand their lives and the spread of their population. Source: grandfailure /Adobe

By Andrew Collins

@ AndrewBCollins

Andrew Collins is a writer of history and science and the author of many books that challenge our view of the past. He lives in the United Kingdom. His site is www.andrewcollins.com