The layers of sediment in a cave in southeastern France can be compared to an archaeological sandwich. Above and below, like slices of bread, are fossils and artifacts associated with Neanderthals, extinct cousins of modern humans.
Most surprising, however, is the “stuffing”: instruments and fossils attributed to the Homo sapiens over 50,000 years old.
For the authors of a new study of the rock shelter, it seems that modern anatomy people and Neanderthals alternately occupied the very same location during the Ice Age — and that was more than ten millennia before the Neanderthals went extinct.
Moreover, the findings in the cave are, for now, the oldest evidence of the presence of members of our species in European territory.
“It’s as shocking a discovery as that of the Chauvet cave in 1994, which at the time revealed the oldest cave with paintings in the world,” says Ludovic Slimak, a researcher at the University of Toulouse-Jean Jaurès and one of the research coordinators. , which has just appeared in the specialized journal Science Advances.
Slimak and his colleagues combined the analysis of fossils and stone artifacts with the precise dating of the various layers of the Mandrin shelter, located in the middle reaches of the Rhône River, one of the most important in the region since prehistoric times.
According to him, one of the factors that facilitated the determination of layer ages was the wind known as mistral, typical of that part of the Mediterranean. As it passed through the Rhône valley, the mistral deposited layers of sand over millennia, which sealed the instruments and bones of Neanderthals and humans in well-defined strata.
“It’s a kind of Pompeii, only without catastrophic aspects”, says the French scientist, comparing the cave where he has worked for 30 years to the Roman city “frozen” by the Vesuvius volcano.
The fossils found in Mandrin’s cave are just teeth, spread over several layers. Luckily, the differences in shape and enamel between Neanderthals and H. sapiens are sufficient to distinguish one human species from another. Although most of the teeth are from Neanderthals, one of them corresponds to that of an anatomically modern child aged between two and six years.
The main clue in the case of our species, however, is stone artifacts. They are small stone points (some with a length of less than 10 millimeters), produced in large quantities and in an extremely standardized way, using techniques very similar to those used on the other side of the Mediterranean, in Lebanon.
The style of Neanderthal stone tools is completely different, with the use of much larger points. The estimated ages for the presence of anatomically modern humans in the cave are between 56,800 years and 51,700 years ago. Before the publication of the work, the oldest records of our species in Europe dated to about 45 thousand years before the present.
For the researchers, the similarity of French artifacts to those of the Eastern Mediterranean is an indication that the first H. sapiens Europeans had mastered some form of navigation that allowed them to travel along the coast of the region.
They associate this ability with other well-known expansions of humanity after it left its African cradle, such as the landing in Australia over 60,000 years ago.
Another crucial point has to do with the chronology of the reoccupations of the cave and the raw materials used by both species.
The “stuffing” with the occupation by H. sapiens appeared in the rock shelter about a year after the Neanderthals left, and the tools used by both types of humans come from the same quarries, within a radius of 100 km.
“Here, we can suspect that there was a direct transmission of knowledge about the terrain from Neanderthals to the H. sapiens. So modern humans would have had direct contact with local populations. They may have had the help of Neanderthal scouts, for example,” speculates Slimak.
The fact that the grotto was reoccupied by Neanderthals decades later, as well as the several thousand years before they disappeared for good, also suggests a much longer process of contact between populations—quite different from a supposed war of conquest by Neanderthals. part of anatomically modern humans. This is also what the DNA data indicate, which show several cases of crosses between the species.
