Neanderthals: How close are we to our extinct relatives?

The known differences between Homo sapiens and Neanderthals appear to grow ever slighter. As scientists prove that we have more in common with those once considered distant cousins of humankind, new writing on the topic has exploded. The deluge of scientific papers, revelatory books and exhibitions focuses on dismantling preconceptions of Neanderthals, who lived in Asia and Europe for at least 300,000 years.

As Israeli historian and essayist Yuval Noah Harari writes: “just by being, Neanderthals challenge some of our most cherished ideals and delusions. Neanderthals force us to question the belief that Homo sapiens is the apex of creation and, more generally, what it means to be human. These questions are now more urgent than ever.”

Neanderthals represent another way of being human and that is something that is very difficult for us to imagine

Paleoanthropologist Juan Luis Arsuaga

Harari was reviewing the bestselling book Kindred. Neanderthal Life, Love, Death and Art by Rebecca Wragg Sykes, a British archaeologist and writer. In the book, Wragg Sykes tries to summarize all the research of the last few decades about Neanderthals, a field that has grown considerably since 2010. That year, researchers at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, sequenced the genome of Neanderthals for the first time. They found that up to 2% of the DNA in the genome of present-day humans outside Africa originated in Neanderthals or in Neanderthals’ ancestors, suggesting that Homo sapiens and Neanderthals interbred.

Spanish writer Juan José Millás and paleoanthropologist Juan Luis Arsuaga have written a philosophical book on this topic, titled La vida contada por un sapiens a un neandertal (or, Life as Told by a Sapiens to a Neanderthal), while paleontologist Bienvenido Martínez-Navarro, in El sapiens asesino y el ocaso de los neandertales (or, Killer Sapiens and the Decline of the Neanderthals), tries to answer the great mystery surrounding the Neanderthals: why did they disappear?

“They fascinate us for the same reason that science fiction fascinates us – because they are another version of ourselves,” says Arsuaga in a phone interview. “Everything indicates that they have the same intelligence as we do, and yet they are not the same. We could say they have the same mind, but not the same mentality. They represent another way of being human and that is something that is very difficult for us to imagine.”

In a video call, Wragg Sykes expresses a similar view. “Neanderthals have changed our perception of ourselves. In Western culture we have always tried to separate ourselves from the rest of nature, to prove that we are better than animals. Neanderthals force us to rethink that.” Wragg Sykes’ book runs through three decades of discoveries about Neanderthals, which also coincide with a revolution in archeology and genetics. The use of chemistry and radiocarbon dating has revealed that the Neanderthals were capable of abstract thought – though not necessarily of producing art. They made use of the plants found in the landscape they roamed, understood the properties of stone to make tools, picked out colors including red and ochre, and they buried their dead and cared for their elders.

The presence of the FOXP2 gene in Neanderthals’ DNA, which is associated with language, means that scientists believe they used some form of communication, an idea reinforced by the animals they hunted, which would have required the cooperation of a group.

“Over the last decade, numerous discoveries have shifted the paradigm about the capabilities of Neanderthals,” says Danish researcher Trine Kellberg Nielsen from the University of Aarhus. A specialist in anthropology and prehistory, Kellberg Nielsen has curated a special exhibition about Neanderthals at the Moesgaard Museum, which will be open until the end of the year (the center is currently closed due to coronavirus restrictions). “Many of the things we once attributed only to our own species, such as a visual culture and social behavior, now extend to Neanderthals,” she explains.

New discoveries seem to accumulate every month, if not every week. Spain offers one of the most fertile grounds for Neanderthal research, and a new study emerged in February regarding beneficial microorganisms in the intestinal bacteria of the Neanderthals from a dig in Salt, Girona. Another from the same month helps us to understand how their brains evolved and influenced their behavior.

They prove that Earth has been home to more than one type of human being

British archaeologist Rebecca Wragg Sykes

That said, much remains unknown. “They are not a failed version of us, and the trajectory from them to us is not teleological: the fact that we are here and they are not is not the point and purpose of her story, or indeed of history,” notes John Lanchester in a review of Kindred. Neanderthal Life, Love, Death and Art in the London Review of Books. “And yet, and yet ... the fact is that we are here and they aren’t, and although that is not the punchline of evolution, the question of why and how this happened is still interesting.”

Most agree that Neanderthals, as Lanchester puts it, “vanish[ed] from the archaeological record with shocking abruptness” 40,000 years ago. Some researchers believe that they survived for thousands of years more in the south of the Iberian peninsula, specifically in Gibraltar, but this theory remains polemical. In his book, Martínez-Navarro provides an explanation based on the struggle for resources. “We were competing for the same resources in the same territory,” he writes, without ruling out violence. However, this is not the most widespread hypothesis among experts. Arsuaga believes that the arrival of Homo sapiens in extreme circumstances – the beginning of a glacial period – was decisive. “In a critical moment, the species that suffers the least prevails,” he explains.

Wragg Sykes puts forward a new theory, based on genetic and chemical studies, that Homo sapiens’ superior weapons and social networks may have helped them survive. “We know from genetics that there was not much difference in their numbers, but also that Homo sapiens were much more interconnected. At a time when the climate was deteriorating rapidly, when you have a network of contacts it’s easier to move to other places, and maybe Neanderthals didn’t have that,” she says. “We know from archaeology that there was no great difference in what they ate, and we have evidence that the Homo sapiens of that period already had weapons that helped them hunt from a distance: darts, arrows, spear-launching systems. The Neanderthals did not.”

The Neanderthals’ demise was probably due to disadvantages in technology, sociability and how they dealt with climate change. But as many of us are still carrying around genetic material from them today, Wragg Sykes notes, “They prove that Earth has been home to more than one type of human being.”