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Study: Neanderthals migrated to Siberia – Twice

Siberia is mainly associated, by non-Siberians, with bitter cold and gulags. Indeed, the average temperature is around minus 5 degrees Celsius (23 degrees Fahrenheit). But southern Siberia is actually temperate forest, characterized by decently habitable summers. The annual temperature averages a balmy 0.5 degrees Celsius – and it seems Neanderthals migrated there not once but twice, researchers reported Monday in scientific journal PNAS.

Categorical evidence of Neanderthal occupation has so far been found in three caves in Siberia’s Altai Mountains, lead author Kseniya Kolobova of the Russian Academy of Sciences explains to Haaretz: the well-known Denisova Cave; Chagyrskaya Cave (the subject of their paper); and Okladnikov Cave.

Based on plant and animal remains, it seems the area of the cave was dry steppe, not tundra. It seems the Neanderthal populations there adapted to life in the dry steppe, the authors say – mainly hunting young and female bison, possibly as they migrated. They also hunted other ungulates: horses, reindeer, Siberian ibex (goats) and argali (large wild sheep). “They hunted bisons and horses in Crimea and in Eastern Europe too,” Kolobova adds.

The stone tools found in Chagyrskaya and Okladnikov are of a markedly different style than those found in Denisova Cave, which is just 100 kilometers (about 60 miles) to the west of Chagyrskaya, the team explains. Wondrously, that technology in Chagyrskaya and Okladnikov is just like a toolkit found at least 3,000 kilometers away, in the general area of Croatia or North Caucasus.

Further supporting the theory of multiple dispersion, the Denisovan Neanderthals lived about 100,000 years earlier than their species-mates in Chagyrskaya and Okladnikov (based on the evidence discovered so far), Kolobova explains.

Analysis of Neanderthal, plant and animal remains shows the Chagyrskayan and Okladnikovan denizens lived 59,000 to 49,000 years ago. There is no evidence that Neanderthals lived in Chagyrskaya at any other time, she adds. The tools found at Chagyrskaya were made of stones from the local riverbed. They weren’t “imported” with migrating populations – but it seems the technology was.

The region called Siberia comprises over 75 percent of Russia, though there are arguments over which provinces are actually encompassed in the definition of “Siberia.”

We shall ignore these geographical distractions and concentrate on the fact that the general region of Siberia was home to at least three types of hominin: Neanderthals, Denisovans and, later, Homo sapiens, too.

It has also become clear that archaic hominins had a huge propensity for wanderlust, going back to the earliest Homo erectus. Also, partly because of this roaming, the prehistory of southern Russia cannot be boiled down to a simple successive occupation by archaics to more modern types to modern humans. There were chronological overlaps between the hominin types, meaning some coexisted. Categorical proof appeared in 2018 with the discovery of the remains of a hybrid Denisovan-Neanderthal teenager in Denisova Cave, dating to 90,000 years ago.

But it has been quite the mystery when the Neanderthals spread from Europe to southern Russia, or where they hailed from. Now we have a clue, at least about the younger ones.

Chagyrskaya lies in the foothills of the Altai chain and is a comfy two-chambered cavern a mere 19 meters above the Charysh River that yielded 74 Neanderthal fossils and no fewer than 90,000 stone tools, the team describes. Deep analysis of more than 3,000 of the distinctive tools found in Chagyrskaya show they are markedly like Micoquien-style tools made by Neanderthals in Eastern Europe, and nothing like the (admittedly earlier) tools found in nearby Denisova.

Micoquien-type tools – named for the riverside site La Micoque in the Dordogne, France, but also found in Neanderthal sites in Eastern Europe – are distinguished by asymmetrical bifaces. They date to around 130,000 to 30,000 B.C.E. (Note that the Neanderthals began living in Micoque around 400,000 years ago, but the specific technology in question took time to develop.)

In other words, the tools found in Chagyrskaya and Okladnikov fit within the younger end of that range.

Denisova Cave had been occupied by Neanderthals between around 100,000 to 200,000 years ago, but no Micoquien-type artifacts were found, Kolobova says.

Further supporting their theory that Neanderthals migrated to Siberia twice: Analysis of DNA from a Chagyrskaya Neanderthal found a closer connection with far-off Neanderthals who lived in Eastern Europe than with a 110,000-year-old Neanderthal from nearby Denisova.

And there we have it: Kolobova and her vast team postulate that the denizens of Chagyrskaya and Okladnikov were a completely different population of Neanderthals who migrated from the region of Croatia, home of the famous Neanderthal haunt Krapina, and/or the North Caucasus. They brought the asymmetrical Micoque knapping technique with them, goes the theory.

The population that had occupied Denisova Cave preceded them by about 100,000 years, if not more, and came from elsewhere.

Credit: Nilenbert, Nicolas Perrault III

So not only did Neanderthals brave the Siberian cold, apparently twice: There is even a theory making the rounds that snowy Siberia is where they made their last stand. That would be instead of Gibraltar.

Until now, stone tools found in Byzovaya in the Ural Mountains – way, way north from our Chagyrskaya Neanderthals – have been assumed to be the manufacture of Homo sapiens. The new theory is maybe they were made by Neanderthals who lasted, in splendid if chilly isolation, until 31,000 years ago.

No bones were found that could categorically show who lived in Byzovaya. The stone tools found there are not necessarily helpful. During the period when Homo sapiens and Neanderthals coexisted in Europe, their techniques were not necessarily distinguishable. Both were capable of making quite sophisticated tools.

One snag for the “Last Neanderthal was in Siberia” theory is that Byzovaya is about 1,000 kilometers north of the other known Siberian Neanderthal sites, as Discover Magazine just explained. Also, it’s bitterly cold – much more so than the climate in southern Siberia. However, hominin fossils are incredibly rare: absence of fossil bones isn’t proof of absence.

On the upside for the theory, it could well be that if the Neanderthals managed to adapt to the bitter cold, they might have clung on because they were left strictly alone for a very long time. And if they were there 31,000 years ago, then they really did hang on longer than in Gibraltar.

The Gibraltar theory touted in 2006 had been based on uncalibrated dating of around 28,000 years ago for Neanderthal remains found in Gorham’s Cave, Prof. Clive Finlayson – the director of Gibraltar National Museum – tells Haaretz. Subsequent calibration resulted in dating of about 32,000 years, he says.

Asked whether he thinks it possible that the Neanderthal remains in Gibraltar might have been hybridized with Homo sapiens (as happened in Israel), he responds: “I don’t think we can discard hybrids at all, especially when relying on archaeological data alone.”

What the Gibraltar remains definitely do show is that Neanderthals survived in isolated pockets even after Homo sapiens began spreading like weeds throughout Europe and Asia.

Finlayson has suggested in the past that the gorgeous climatic conditions on Gibraltar contributed to the Neanderthals’ longevity there, which – even if not quite as recent as once thought – sounds plausible.

It is also possible that whoever lived at Byzovaya wasn’t exactly Neanderthal. It’s plausible that the maker of tools there 31,000 years ago was some kind of hybrid, equipped with Neanderthal brawn, Denisovan resistance to cold and altitude, and sapiens smarts.

Header: Alexander Fedorchenko (Russian Academy of Sciences)