What, or who, were the Neanderthals?

The story of the Neanderthals begins around 800,000 years ago with the emergence of a group of hominids which was known as the Homo heidelbergensis. 

Early humans like these who lived in Africa and Western Eurasia are considered the common ancestors of both Neanderthals and modern humans. 

However, the two species of humans began splitting around 600,000 to 500,000 years ago when some Homo heidelbergensis populations remained in Africa and they eventually gave rise to Homo sapiens while others migrated north into Europe and Asia. 

When they reached the harsh climates of Ice Age Europe these northern Homo heidelbergensis populations evolved into the Neanderthals. 

The first Neanderthals are estimated to have appeared around 400,000 years ago and they continued to evolve and adapt to their environment over the next several hundred thousand years.

Neanderthals expanded their range from Western Europe into the Middle East and Central Asia around 130,000 years ago during a period which was known as the last interglacial. 

Neanderthal expansion occurred at a time when their culture became more advanced and included the development of new types of stone tools and the use of fire.

Neanderthals had several physical characteristics that set them apart from their hominid relatives. 

Fossil evidence from a nearly complete Neanderthal skeleton found in 1908 at La Chapelle-aux-Saints in France was an important part of our understanding of Neanderthal anatomy and lifestyle. 

The skeleton showed that Neanderthals were well adapted to the cold with short, stocky bodies and large nasal cavities. 

Such traits seem to have helped them survive the harsh climates of Ice Age Europe and Asia. 

Such traits meant that Neanderthals had a strong build. 

In fact, they were shorter and stockier than modern humans with males who stood about 164 to 168 cm (about 5.4 to 5.5 feet) tall and females who stood about 152 to 156 cm (about 5 to 5.1 feet) tall. 

Researchers suggest that this compact body shape helped to conserve heat and gave them an important advantage in cold climates. 

In addition, their limbs were also shorter and more muscular likely the result of a physically demanding lifestyle.

Also, Neanderthals had a large, elongated skull with a low, receding forehead and prominent brow ridges. 

Their faces were broad and jutting and their large nasal cavities were likely an adaptation to the cold, dry air of their environment. 

The large nose would have warmed and humidified the air before it reached the lungs reducing the risk of respiratory infections. 

Inside their skulls, Neanderthals had a brain that was as large as or larger than that of modern humans and this suggests they had high mental abilities.

The Neanderthals were very adaptable and could survive in many habitats across a wide area. 

Their territory spanned much of Eurasia from the Atlantic coasts of Europe to the mountains of Central Asia and the fertile plains of the Middle East. 

The first recognized Neanderthal fossil was discovered in 1856 in the Neander Valley which is called Neandertal in German near Düsseldorf, Germany which led to the naming of the species Homo neanderthalensis by Irish geologist William King in 1864. 

For much of their history, they were primarily a European species, but they also thrived in the temperate forests and grasslands that covered much of the continent during the warmer interglacial periods. 

In addition, they could live in the tundra-like environments that prevailed during the colder glacial periods. 

Because of this, Neanderthal sites have been found in places like Northern Germany and parts of Scandinavia and their range even reached the far east of Asia where another hominid species the Denisovans lived. 

Evidence from Denisova Cave in Siberia shows that Neanderthals interbred with the Denisovans. 

Also, Neanderthal remains have recently been found in the Altai Mountains in Siberia.

Our understanding of Neanderthal culture and social structure is still developing but archaeological and genetic evidence suggests that Neanderthals had a detailed social organisation. 

Firstly, genetic studies suggest that Neanderthal populations were generally small and fragmented with total numbers possibly never exceeding 70,000 individuals. 

However, individual Neanderthal groups or bands probably consisted of only a few dozen individuals. 

These were probably based on close kinship ties. 

Interestingly, some studies of Neanderthal juvenile fossils suggest they had similar growth rates to modern human children but seem to have reached physical maturity earlier.

Neanderthals also show some behaviours similar to modern humans. 

They made their own tools, and they used the stone tool technology known as the Mousterian, which involved shaping flint cores to produce tools such as scrapers, points, and hand axes. 

Tools like these were used for tasks such as butchering animals and processing plant materials. 

Some engraved artefacts and cave paintings found in sites like Cueva de los Aviones and La Pasiega in Spain suggest that Neanderthals engaged in artistic and symbolic activities. 

They used pigments such as ochre possibly for body decoration or artwork and made unusual structures from stalagmites like those found in Bruniquel Cave in France. 

The interpretation of these findings is still debated but they raise the possibility that Neanderthals had a symbolic culture like ours. 

There is also evidence that Neanderthals used fire for cooking and for warmth. 

At the site of Sesselfelsgrotte in Germany, flint artefacts underwent intentional heat treatment by Neanderthals which shows an advanced understanding of fire use to improve the flaking of the stone. 

Such a control and use of fire would have been an important technical accomplishment. 

Perhaps the most interesting evidence of Neanderthal culture comes from their burial practices. 

At several sites, Neanderthals have been found buried in what appear to be intentional graves, sometimes with animal bones or other items. 

Findings at Shanidar Cave in Iraq, which is where Neanderthal skeletons were found alongside pollen from flowers, suggest that Neanderthals may have performed ritual burials. 

Evidence from burial findings shows that Neanderthals had an idea of death and possibly beliefs about an afterlife. 

Finally, the discovery of a well-preserved Neanderthal hyoid bone, which is similar in shape to that of modern humans, suggests that Neanderthals may have had the physical ability for speech. 

The high occurrence of healed injuries in Neanderthal skeletons implies that they cared for their sick and injured, which showed a level of social bonding and empathy.

Archaeological and isotopic evidence on the dental remains of Neanderthals suggests that they had a diet made up mainly of meat. 

Their food likely included a variety of Ice Age megafauna such as woolly mammoths, woolly rhinoceros, bison, and reindeer, which means that they must have been skilled hunters to bring down large creatures. 

Also, hunting these animals would have required a high level of planning and teamwork, which suggests that Neanderthals had advanced social and thinking abilities.

Evidence of trauma indicates that they took part in close-range hunting of large, dangerous animals, such as the ‘surround and drive’ method, which involved a group of hunters encircling a herd of animals and pushing them toward a kill zone. 

While meat was a key part of the Neanderthal diet, they also ate a variety of plant foods, as tiny plant remains found in Neanderthal dental plaque suggest that they consumed nuts, berries, and tubers. 

The diet of Neanderthals may have also included marine resources. At some coastal sites, Neanderthals have been found with shellfish and marine mammals, which suggested that they used marine areas for food. 

As a side note, chemical analysis of Neanderthal dental plaque also found traces of plants like yarrow and chamomile, which were often used for medicinal self-care.

The two different species of humans actually lived together in Eurasia for several thousand years. 

When Homo sapiens first arrived in Eurasia around 120,000 to 100,000 years ago, they were in direct competition with Neanderthals. 

This competition could have taken the form of direct conflict. 

However, there is also evidence of more peaceful interactions between the two species. 

Archaeological sites show that Neanderthals and Homo sapiens used similar types of stone tools, suggesting that they may have learned from each other. 

There are also cases of Neanderthal sites being reused by Homo sapiens, showing a degree of cultural connection. 

Recent studies using improved radiocarbon dating methods show that Neanderthals became extinct around 40,000 years ago, shortly after the arrival of Homo sapiens in Europe. 

Gorham’s Cave complex in Gibraltar is one of the last known homes of Neanderthals, with evidence showing they lived there around the time they went extinct. 

There are several ideas about why the Neanderthals went extinct. One of the most discussed ideas is competition with Homo sapiens. 

According to this idea, Homo sapiens, with their advanced technology and detailed social structures may have outdone Neanderthals in getting resources.

Another idea is that the Neanderthals could not adjust to changing climates. 

The period when the Neanderthals went extinct saw harsh and fast climate swings, with cold, dry times alternating with warmer, wetter times. 

Such swings could have disrupted the ecosystems that the Neanderthals depended on, making it harder for them to find food and other resources. 

A third idea is that the Neanderthals were wiped out by diseases brought by Homo sapiens. 

As modern humans moved out of Africa, they may have carried with them germs to which the Neanderthals had no resistance. 

Uncertainty surrounds the ‘disease idea’, but it is supported by the fact that contact between human groups has often led to the spread of diseases.

One of the most interesting discoveries in recent years is the presence of Neanderthal DNA in the genomes of modern humans. 

In 2010, geneticist Svante Pääbo and his team at the Max Planck Institute successfully sequenced the Neanderthal genome, which provided groundbreaking insights into the genetic relationship between Neanderthals and modern humans. 

It showed that modern humans outside of Africa carry about 1.8 to 2.6 per cent Neanderthal DNA in their genomes. 

Interbreeding between the two species likely happened in the Middle East shortly after Homo sapiens left Africa and possibly also later in Europe, resulting in these genetic traces.

However, the Neanderthal DNA in modern humans is not spread evenly throughout the genome. 

Instead, it is found in certain regions, which suggests that some Neanderthal genes were helpful and were kept over time. 

Genes like these are linked to a range of traits including skin and hair colour, immune response, and even brain traits. 

For example, some versions of the MC1R gene, which is involved in skin and hair pigmentation are thought to have come from Neanderthals and may have helped modern humans adapt to the lower light levels in Europe. 

On the other hand, there are also regions of the modern human genome that have almost no Neanderthal DNA. 

Such ‘deserts’ of Neanderthal ancestry may represent areas where Neanderthal genes were harmful and were removed over time. 

For example, genes involved in male fertility are notably missing in Neanderthal ancestry, suggesting that male offspring of Neanderthal–Homo sapiens unions may have been less fertile.

However, the presence of Neanderthal DNA in modern humans has important effects on our understanding of human evolution. 

It shows that the story of human evolution is not a simple tree with branches neatly splitting off from each other, but rather a network of interconnections, and it challenges the traditional view of Neanderthals as a separate, primitive species and instead shows Neanderthals as our close relatives who share a common history and a common genetic heritage.