Denisovans had archaic teeth – and fingers like ours, according to a new study – Archeology

berkele The more we learn about human evolution, the more our chronic becomes cloudy. Science has revealed that even though the teeth and jaw of the Denisovans seemed archaic, similar to those of Homo erectus or even Australopithecus, their fingers were like ours.

Denisovan's fingers were as graceful as those of modern man, explains Professor Eva-Maria Geigl of the Jacques Monod Institute at the University of Paris, and not squat-like fingers like their sister kind, Neanderthals.

"The Denisovans had fingers that were indistinguishable from modern humans," the team reported Wednesday in Nature.

This karst explosion is based on minute measurements of a piece of finger bones found in Denisova's famous cave, but it records volumes.

To be precise, the fingerbone found in Denisova's cave had been cut in half to be analyzed by different teams. some suffered what it suffered at the Max Planck Institute in Germany, and the other, bigger, was misplaced, but eventually sent to the University of California, Berkeley. and finally to his lab, says Geigl, who did the research with colleagues from his own team colleague as well as from the University of Bordeaux and the University of Toronto.

Before genomic analysis, Geigl measured and photographed the finger fragment. The mitochondrial genome produced in his lab was identical to the one that had produced the genome in 2010 and 2012, confirming that it was the missing part of the phalanx (finger bone). The bone fragment itself was then returned to Berkeley.

When science took the image of the largest room and digitized it in 3D on its small base and virtually united them, she could for the first time meticulously analyze what a part of the post-cranial body looked like. a Denisovan. Science could compare this finger with those of modern man and Neanderthal man. And science was powerfully surprised.

This touch of Denisovan

The existence of an unknown species of Homo known as Denisovans was discovered in 2010 by the genetic analysis of a tiny fragment of finger bone discovered in the cave of Denisova, in the mountains of the Altai.

The finger was revealed to belong to an unknown species of archaic human that was neither Neanderthal nor Homo sapiens.

Nearly ten years later, remains of Denisovan were found exactly in two places, no more: this cave; and 2,400 kilometers further on the Tibetan plateau, where a jaw with teeth was discovered in May. (It should be added that among the very rare hominin skeleton fragments found in Eurasia, others – even many others – could also be Denisovan, but there is no evidence.)

So that's all. There are only a few teeth left among our extinct ancestors, a finger whose parts are now united, and the jaws of Siberia and Tibet. Yet genetic analyzes of these teeth and their deduction led to the postulation that Denisovans was going all over Southeast Asia. One of the main contributors to this theory is the discovery that current Melanesians have a high proportion of Denisovan genes, from 4% to 6%, and that Tibetans and early Australian settlers, Aborigines, also have a clear mark of Denisovan. .

Genetic analyzes suggest that the proto-Neanderthals and the precursor-Homo sapiens split about 700,000 years ago (the exact date dispute is raging). Then, the ancestral Neanderthal line in Europe itself split about 400,000 years ago, in Neanderthals in the west and Denisovans in the east.

Despite their division and speciation, Neanderthals and Denisovans coexisted and mixed in some places – many – including Denisova Cave. Archaeologists have identified a 90,000-year-old bone belonging to a first-generation Neanderthal-Denisovian hybrid teenager.

Another study conservatively estimated that Denisovans lived in the cave 287,000 to 55,000 years ago and Neanderthals lived there at least twice in prehistory: about 193,000 and 97,000 years ago.

While they were traveling through Asia, the Denisovans themselves apparently also split up. On the basis of divergent traces of Denisovan ancestry in our own genes, scientists deduce that there were at least two distinct populations of Denisovans.

All of this has led to many futile discussions about whether we, Homo sapiens sapiens, are the same species as Denisovans and Neanderthals, given that we could and we were crossed, and that we were going so happily with a crowd other hominins. Geigl, a geneticist by profession, does not defend the camp of separate species. For what it's worth, we mingled with them and there were profound morphological differences.

But what did the Denisovans look like? We have only three teeth of Denisova's cave and the mandible discovered in Tibet. We can not reconstruct either the face or the body.

All we can say is that Denisovan's jaw does not look like ours. No DNA was extracted from this old mandible), but that said, its shape is archaic, retaining some features of Homo erectus and some Neanderthal traits. Denisovan's teeth are larger than ours and more archaic.

"From there, we could have expected that the bone of the finger – the only post-skeletal skeletal element ever found in the Denisovans – is also archaic," explains Geigl. But that was not the case. "To our surprise, it's like Homo sapiens," she told Haaretz. Ergo, the Denisovan is a mosaic of primitive and advanced features.

All this information on Denisovan's finger leads to a new postulation, which concerns neither Denisovans nor us, but the Neanderthals.

To know that maybe we and the Denisovans are the ones who keep an archaic morphology, slender fingers. The more archaic hominins seem to have had the same kind of slender fingers as we do. Neanderthal's fingers may have evolved in a different direction, suggests Geigl.

But is it art?

The approximate fingers and dexterity, bone points and dental pendants found in Denisova's cave are 49,000 and 43,000 years old – which, according to the chronologies of the Denisovan and Neanderthal occupation, suggests that they have been manufactured by Denisovans. Bone spikes are thought to have been used in garment making simply by drilling holes in the skin, through which some kind of fiber would be threaded.

These bone points and dental pendants would be thousands of years older than, for example, the famous Venus of Hohle Fels mammoth ivory found in Germany – it may be as old as 40,000 to 35,000 years old.

In other words, the artifacts found in Denisova's Cave could be the oldest artifacts known in Europe. Beyond Europe, it should be added that we could count pearls more than 100,000 years old (especially seashells with perforation holes) found in Skhul, Israel. The jury remains completely on the "Venus of Berekhat Ram", Israel, which dates back to a quarter of a million years, but could be a pebble with vaguely mammary prominences, not a statuette.

Given new theories that early Homo sapiens Further and wider than we thought, and earlier than expected, we do not know who made these bone points and pendants in Siberia. But the thought that craftsmen were Denisovan is intriguing – especially since "Neanderthal art" discovered in Europe may not be that.

Earlier this year, 200,000-year-old teeth discovered in the Yanhui Cave in Tongzi, southern China, had made things even more complicated. These teeth did not come from either Homo erectus or Neanderthals, but from whom they could originate remains unknown.

The bottom line is that palaeontologists frantically painting Eurasia in search of Denisovan's remains may have barked the bad trees if they were looking for archaic traits in hominin fossils, Geigl notes.

"They would be well advised to look for other features too," she summarizes. The discovery also teaches us something about the continuity of certain characteristics, namely the circumference of our fingers. And why could Neanderthals have developed stronger fingers? Who knows, maybe environmental problems.