There is a scene that is easy to imagine, even if no one will ever be able to photograph it: a small human group moving in a cold, unstable, capricious Europe. Food changes area, animals migrate, the climate changes, a valley becomes less hospitable, one passage closes, another opens. In that world, surviving meant knowing the territory, of course. Knowing how to hunt, make tools, read tracks. But it also meant having someone to reach out to when one’s piece of the world became too narrow.
The new hypothesis on disappearance of the Neanderthals it starts right here: from connections. Climate and competition withHomo sapiens they remain within the story, but on their own they explain too little. The study published on Quaternary Science Reviews suggests a more irregular and more human picture: Neanderthals had networks between groups, exchanges, contacts, movements of materials; their connections, however, seem to have been more fragile, more regional, less capable of withstanding repeated environmental shocks than those of the sapiens.
The disappearance of the Neanderthals
The work was led by Ariane Burke, anthropologist at the Université de Montréal, together with a research group that adapted tools usually used in digital ecology to prehistory. In practice, models created to understand where plants and animals can live have been applied to ancient human populations. Instead of modern observations of a species, the researchers used archaeological sites as points of presence, that is, as material traces of where Neanderthals and Homo sapiens they lived or moved.
The period observed is one of the most delicate phases of European history: between 60,000 and 35,000 years agoduring the last glacial cycle. In those millennia the climate fluctuated between cold phases, called stadiums, and milder phases, called interstadials. It is also the period in which the first sapiens appear permanently in the European archaeological record and Neanderthals progressively disappear from material traces.
The researchers built four habitat suitability models for each of the two species, using archaeological data, geographic information and indices related to climate variability. Then they looked for so-called “core” areas: regions large, productive and stable enough to support populations over time, especially if connected to other similar areas. Here the difference between the two groups became more evident. The areas favorable to sapiens were on average more connected. Those of the Neanderthals, although present and sometimes resistant, formed less solid networks, especially in central and eastern Europe.
To provide a concrete measure, the team also used ethnographic data from better documented hunter-gatherer populations. A local group of 25-50 people, with seasonal movements and relationships with other regional groups, could use an annual territory of approximately 2,500 square kilometers. An enormous surface if we look at it with modern eyes, yet barely sufficient in an environment where survival depended on mobility, the seasons, animals and the possibility of relying on others.
Social networks as a refuge
The word “network” may seem too contemporary, almost like social media. Here he has a very different subject. A network, in this case, means knowing where the herds are passing, having links with neighboring groups, exchanging information, forming pairs, building alliances, obtaining temporary access to a territory when a crisis makes your own less liveable. In an unstable Europe, a connection could be as good as a well-made tool.
Neanderthals, it must be said clearly, were far from isolated. Archaeological evidence on the movement of materials between regions shows contact and exchange. The old image of the closed, backward group, stuck in its own valley, holds up less and less. The difference indicated by the models lies in the connection resilience: those of the sapiens seem more flexible, more extensive, more capable of offering alternatives when the climate or demographics put pressure.
The study also adds an important detail: climate variability, i.e. the speed and unpredictability of changes, would have weighed more than average temperatures or average rainfall. Neanderthals had already gone through very harsh glacial periods, so the cold itself explains little. The problem appears to have been the intertwining of environmental instability, vulnerable populations, geography and less robust social bonds in some areas.
The situation then changed from region to region. In Europe the Neanderthals seem to be divided into two large groups, one western and one eastern. In the east, weaker connections between suitable areas might have promoted isolation when conditions worsened. In the Iberian Peninsula, at the western extreme of their range, more connected nuclei may instead have sustained a longer persistence. Even the arrival of the sapiens in the western areas could have added pressure to already fragile populations.
The contact between Neanderthals and sapiens, moreover, was complicated. The two species met, competed in some contexts, shared territories and in some cases had children together. Genetics has long shown this: part of the Neanderthal inheritance is still present in modern humans. In this context, talking about “replacement” as if it were a single and clean event risks flattening a history made of overlaps, contacts, local pressures, adaptations and genetic absorption.
The most current detail of a 40,000 year old story
The most interesting part of the study lies in its caution. Researchers do not deliver a single cause, nice and convenient, to be put in the title and forgotten. There disappearance of the Neanderthals appears as the result of many factors that add up in different ways: unstable climate, habitat distribution, population density, possibility of moving, encounters with sapiens, demographic fragility, more or less elastic social networks.
This reading also takes away the strength of another convenient idea: that according to which the sapiens won because they were simply more intelligent or more technological. The benefit may have been more everyday, more relational, almost more banal. Have connected groups. Know where to go. Being able to reach relatives, allies, partners. Moving to better areas when one area stopped being enough. Bring information from one territory to another.
It is an ancient lesson, with a very contemporary shade. Human migrations have always existed for this reason too: looking for more favorable places, reuniting with loved ones, joining help networks. Today there are borders, states, inequalities, documents, rejections, entire economies built on mobility granted to some and denied to others. Forty thousand years ago there was ice, steppes, animals, hunger, bonds. Change the bureaucracy. The movement remains.
Neanderthals did not disappear because they were unable to adapt. They had withstood extreme climates, developed material cultures, and inhabited Europe for hundreds of thousands of years. Perhaps, when the world began to change too frequently, some of their networks no longer offered enough roads. And in a continent that cooled, warmed, broke apart and reassembled itself, one more road could make the difference between staying and vanishing.
