Perched about 100 metres up the slopes of the Prealps in southern France, a humble rock shelter appears out over the Rhône River Valley.
It’s a strategic level on the panorama, as right here the Rhône flows by way of a narrows between two mountain ranges.
For millennia, inhabitants of the rock shelter would have had commanding views of herds of animals migrating between the Mediterranean area and the plains of northern Europe, right now changed by TGV trains and as much as 180,000 automobiles per day on one of many busiest highways on the continent.
The positioning, recognised within the Sixties and named Grotte Mandrin after French folks hero Louis Mandrin, has been a valued location for over 100,000 years.
The stone artifacts and animal bones left behind by historical hunter-gatherers from the Paleolithic interval have been shortly coated by the glacial mud that blew from the north on the well-known mistral winds, preserving the stays nicely preserved.
Since 1990, our analysis staff has been fastidiously investigating the uppermost three metres of sediment on the cave ground.
Primarily based on artifacts and tooth fossils, we imagine that Mandrin rewrites the consensus story about when fashionable people first made their solution to Europe.
Human origins researchers have typically agreed that between 300,000 and 40,000 years in the past, Neanderthals and their ancestors occupied Europe.
Once in a while throughout that interval, they'd contact with fashionable people within the Levant and elements of Asia.
Then round 48,000 to 45,000 years in the past, fashionable people – primarily us – expanded all through the remainder of the world, and Neanderthals and all different archaic people disappeared.
Within the journal Science Advances, we describe our discovery of proof that fashionable people lived 54,000 years in the past at Mandrin.
That’s some 10 millennia sooner than our species was beforehand regarded as in Europe and over 1700km from the next-oldest recognized web site, in Bulgaria.
And fascinatingly, Neanderthals seem to have used the cave each earlier than and after the trendy human occupation.
Clues from tiny stone factors and a tooth
The primary curious discovering to emerge throughout the preliminary decade of Grotte Mandrin excavations have been 1500 tiny triangular stone factors recognized in what we labelled Layer E. Some lower than 1cm in size, these factors resemble arrowheads.
They don't have any technological precursors or successors within the 11 surrounding archaeological layers of Neanderthal artifacts within the cave.
Who made them?
A handful of different websites within the center Rhône Valley additionally include these tiny factors.
However these websites have been excavated way back with pickaxes, making it onerous to inform whether or not the factors confirmed up abruptly or steadily over time, maybe with Neanderthals having developed the strategies to make them.
In 2004, considered one of us, Ludovic Slimak, named this distinctive custom “Neronian” after the close by web site the place such tiny factors have been first excavated.
With out extra native websites for comparability, two of us, Laure Metz and Slimak, appeared to a area the place fashionable people have been undoubtedly dwelling by 54,000 years in the past: the Japanese Mediterranean.
Specifically, the location of Ksar Akil close to Beirut preserves what stands out as the longest and richest Paleolithic document in all Eurasia.
Our analyses of the stone artifacts from Ksar Akil present a equally aged sediment layer with tiny factors of the identical measurement and made in the identical technical traditions as these of Mandrin.
This similarity strongly advised that the Neronian artifacts have been made not by Neanderthals, however quite by a bunch of contemporary human explorers who entered the area a lot sooner than we had anticipated.
The ultimate piece of the puzzle got here in 2018, when considered one of us, Clément Zanolli, analyzed the 9 hominin enamel we’d discovered all through the totally different layers throughout excavation.
Via painstaking analyses utilizing CT scans and comparisons with tons of of different fossils, we have been capable of decide that the Mandrin E tooth, a single child tooth from a baby between two and 6 years of age, got here from an early fashionable human and can't be from a Neanderthal.
Primarily based on the stone level applied sciences and their contexts in different websites, together with this fossil proof, we conclude that the makers of the Neronian factors in Grotte Mandrin have been fashionable people.
Studying campfire soot layers like tree rings
However the discoveries from Mandrin don’t cease there.
All through the location’s layers there are fragments of the shelter partitions and roof which have fallen off and been buried with the fossils and artifacts.
When Neanderthals and fashionable people made fires within the web site, the smoke would depart a layer of soot on these surfaces.
Then the next season a skinny layer of calcium carbonate referred to as speleothem would cowl it over.
This cycle was repeated again and again.
We first found these sooted vault fragments in 2006, and the staff recovered hundreds, 12 months after 12 months, in each archaeological layer of Mandrin.
A decade of labor by staff member Ségolène Vandevelde has proven that these patterns will be learn like tree rings to inform us with what frequency and length the teams visited the location, demonstrating that human teams got here to Mandrin some 500 occasions over 80,000 years.
Traces written by 'naughty pupils' amongst 18,000 pottery fragments
Ms Vandevelde was then capable of decide how a lot time separated the final Neanderthal fireplace from the primary fashionable human fireplace within the cave, displaying that it was solely a most of a 12 months between Neanderthals utilizing Grotte Mandrin and fashionable people shifting in.
After the trendy people occupied Mandrin yearly for some 40 years, one or two generations, they disappeared simply as shortly and mysteriously as they'd appeared. Neanderthals then usually reoccupied Mandrin over the next 12,000 years.
A number of human species sharing the panorama
How did these fashionable people arrive so early in Western Europe?
Archaeological proof from Australia reveals that fashionable people reached that continent by as early as 65,000 years in the past.
After all they'd have wanted a ship to cross the open ocean to get there. It subsequently isn’t a stretch to imagine that individuals within the Mediterranean had entry to boat applied sciences 54,000 years in the past and used them to discover alongside the coastlines of this contained sea.
We all know from the supply areas of the flint used to make the artifacts in Grotte Mandrin that each Neanderthals and fashionable people roamed broadly, about 100km in all instructions across the web site.
How did the trendy people find out about all these stone sources over such a big, different panorama in such a short while?
Did they've relationships with the Neanderthals, who may have exchanged data or acted as guides? Was this a second when the 2 teams interbred?
Our ongoing work at Mandrin will make clear these and different questions on our earliest ancestors in Europe.
Written by Ludovic Slimak, Université Toulouse; Jean Jaurès, Clément Zanolli, Université de Bordeaux; Jason E. Lewis, Stony Brook College (The State College of New York); and Laure Metz, College of Connecticut