We are the only human species left on Earth.

Once, we shared our planet with other human species, including Neanderthals and Denisovans. Today, they’re gone, leaving behind fossils, ancient tools and traces of their DNA within our own. So how did Homo sapiens end up as the last humans standing?

For decades, we believed our ancestors survived because they were smarter, stronger or better adapted. But what if the real secret to our success was something far more unexpected? What if we survived because we were friendlier?

Some researchers believe our ability to cooperate, build relationships and form larger social networks may have given us a crucial evolutionary edge, an advantage of just 2 per cent that, over thousands of years, could have changed the course of human history.

Wooden tools, weapons, building materials and domestic items discovered in a Spanish cave challenge the assumption that Neanderthals’ technological life was based primarily on stone.

The finds have given an unprecedented glimpse into everyday Neanderthal life and are a rare opportunity to recover part of their missing world, says at the Catalan Institute of Human Paleoecology and Social Evolution in Spain.

“Neanderthal technology was not only made of stone; it was also made of wood,” he says.

“The archaeological record gives us a very biased picture of prehistoric technology. We see the stone because it survives, while a huge part of their material culture has simply disappeared.”

Vallverdú and his colleagues have now completed the first systematic review of nearly 600 wooden objects, all between 40,000 and 62,000 years old.

The finds have been collected by generations of archaeologists since the 1980s, excavated at a rock shelter site called Abric Romaní near Barcelona. They include timber imprints in travertine – a rock rich in calcium carbonate that precipitates out of water in certain environments. The rock preserves the patterns of the wood grain even though the timber long ago rotted away. Charred artefacts and actual preserved timber have also been found at the site.

The researchers’ first job was to determine exactly which pieces were used or made by Neanderthals. Only 13 qualified. Most of the remainder consist of trunks, branches, twigs, roots and firewood accumulations.

, also at the Catalan Institute, says the researchers have been surprised at how “complex Neanderthal woodworking could be, and how well they understood the properties of wood”, with the two spears being especially striking to her.

“Producing long, straight shafts and shaping them deliberately into pointed weapons required planning, skill and careful selection of the raw material,” says Chacón.

The technological behaviours preserved at Abric Romaní are comparable to those documented for Homo sapiens, she says.

Other finds included a mysterious wooden tripod, as well as timber trays reminiscent, in terms of likely utility, of the coolamons traditionally used by Indigenous Australians to carry food and water. Some of the wooden objects appear to be structural poles.

But perhaps the item that has most surprised the team is a “club-like” object that has no precedent from any other palaeolithic site.

, also at the Catalan Institute, says the club-like object is “not simply a stick with a thicker end”.

“There is a distinct narrow handle and an enlarged, asymmetrical head, giving the object a much more complex and deliberate form,” she says. “This particular configuration is what we have not been able to find a convincing parallel for in the prehistoric record.”

Vallverdú says the site shows that wood was a normal and important part of Neanderthals’ everyday life.

“We have evidence of woodworking across many archaeological levels and over thousands of years, and the objects are associated with very different activities: hunting, domestic tasks, containers and the organisation of living spaces,” he says.

at the Natural History Museum in London says the archaeological record of wooden artefacts has been “severely constrained” by the generally poor preservation of organic materials.

The finds reveal a much wider technological repertoire of woodworking skills, he says.

The story of the first human tool: the humble container

An analysis of ancient human artefacts finds that the container, a simple but critical tool, may have originated 500,000 years ago. Columnist Michael Marshall explores how slings, ostrich eggs and wooden trays helped our ancestors survive

“This is of course evidence from only one site, in one area, and one time span,” says Stringer, “so it’s just the tip of the iceberg in terms of a whole and mostly hidden technology that ran in parallel with the much better-known stone tools of the Palaeolithic.”

“Wood, plant fibres, hides, bone and other organic materials must have been central to daily life, but they normally disappear,” says , also at the Catalan Institute. “So when a site like Abric Romaní preserves wooden imprints and charred wooden objects, it is almost like suddenly seeing the missing half of the toolkit.”

at Kyoto University in Japan describes the wooden objects as “remarkable”.

“Preserved organic materials are truly rare, and they reveal a ‘hidden’ aspect of Neanderthals that we have been missing,” says Morimoto.

At Grotte Mandrin in France, a Neanderthal discovery has challenged everything we know about our human relatives. We travelled to the cave to meet palaeoanthropologist Ludovic Slimak, who discovered Thorin, one of the last known Neanderthals, reshaping our understanding of human history.

From the remarkable preservation of remains to the groundbreaking DNA evidence there, Slimak explores how an isolated Neanderthal population survived for tens of thousands of years, even interacting with early Homo sapiens, before disappearing. Thorin’s story challenges assumptions about intelligence, identity and survival, offering a new perspective on what it means to be human.

Homo sapiens aren’t as unique as we once thought. In fact, only about 1.5 to 7 per cent of our DNA originated in our species alone. Everything else we share with our ancestors and those human species we once coexisted with, including Neanderthals, Denisovans and even some yet-to-be-identified “ghost populations”. This rewrites the story we have told ourselves about our species. We just aren’t that unique.

When our ancestors met these other human species, they didn’t just compete with them: they mated with them. And those encounters left a permanent record in our DNA. In other words, those ancient humans we thought had vanished didn’t necessarily disappear… Some of them are still here inside you.

Read more: How Homo naledi is changing what we know about death

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