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 known as the Homo heidelbergensis.

These early humans, 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 (eventually giving 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.

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

This expansion coincided with a period of increased innovation in Neanderthal culture, including the development of new types of stone tools and the use of fire.

Neanderthals had a number of 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 pivotal in shaping our understanding of Neanderthal anatomy and lifestyle.

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

These traits appear to have specific adaptations to the harsh climates of Ice Age Europe and Asia.

This meant that the Neanderthals had quite a robust physique. In fact, they were shorter and stockier than modern humans, with males standing about 164 to 168 cm (approximately 5.4 to 5.5 feet) tall and females about 152 to 156 cm (approximately 5 to 5.1 feet) tall.

It is theorized that this compact body shape helped to conserve heat, which would have given them a crucial advantage in cold climates.

In addition, their limbs were also shorter and more muscular, probably 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 projecting, 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 even larger than, that of modern humans, suggesting a high degree of cognitive ability.

The Neanderthals were a remarkably adaptable species, capable of surviving in a variety of habitats across a wide geographic range.

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 (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.

As a result, Neanderthal sites have been found in regions like Northern Germany and parts of Scandinavia, and even reached the far east of Asia, where another hominid species, the Denisovans, were present.

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

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

While our understanding of the culture and social structure of Neanderthal life is still evolving, archaeological and genetic evidence suggests that Neanderthals had a surprisingly complex social organization.

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, were likely to only consist of 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.

Also, Neanderthals seem to demonstrate some behaviors that are similar to modern humans.

They were able to make their own tools, especially using the distinctive stone tool technology known as the Mousterian, which involved the careful shaping of flint cores to produce a variety of tools, including scrapers, points, and hand axes.

Such tools were used for a range of tasks, from butchering animals to processing plant materials.

Also, some engraved artifacts 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 created enigmatic structures from stalagmites, like those found in Bruniquel Cave in France.

While the interpretation of these findings is still controversial, they raise the possibility that Neanderthals had a symbolic culture, much like our own.

In a similar way, there is also evidence that Neanderthals used fire, both for cooking and for warmth.

In a site at Sesselfelsgrotte in Germany, flint artifacts underwent intentional heat treatment by Neanderthals, which indicates a sophisticated understanding of fire use to improve the flaking properties of the stone.

Such a control and use of fire would have been a significant technological achievement.

Perhaps the most intriguing 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 objects.

Discoveries at Shanidar Cave in Iraq, where Neanderthal skeletons were found alongside pollen from flowers, suggest that Neanderthals may have practiced ritualistic burials.

This suggests that Neanderthals had a concept of death and perhaps even 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 anatomical capability for speech.

The high incidence of healed injuries in Neanderthal skeletons suggests that they cared for their sick and injured, indicating a level of social cohesion and empathy.

Archaeological and isotopic evidence on the dental remains of Neanderthals suggests that they had a diet composed primarily 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 in order to bring down large creatures.

Also, hunting these animals would have required a high degree of planning and cooperation, which suggests that Neanderthals had sophisticated social and cognitive abilities.

Hunting was quite a dangerous activity, as Neanderthal fossils often exhibit trauma patterns similar to those of modern rodeo professionals.

This indicates that they engaged in close-range hunting of large, dangerous animals, such as the 'surround and drive' strategy, in which a group of hunters would surround a herd of animals and drive them towards a kill zone.

While meat was a crucial part of the Neanderthal diet, they also consumed a variety of plant foods, as microscopic plant remains found in Neanderthal dental plaque suggest that they ate 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, suggesting that they exploited marine environments for food.

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

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

In fact, there is even compelling evidence of both conflict and cooperation, as well as interbreeding.

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 instances of Neanderthal sites being reoccupied by Homo sapiens, indicating a degree of cultural continuity.

Recent studies using improved radiocarbon dating methods indicate 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 habitations of Neanderthals, with evidence indicating they lived there around the time they went extinct. 

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

According to this theory, Homo sapiens, with their advanced technology and complex social structures, may have outcompeted Neanderthals for resources.

Another theory is that the Neanderthals were unable to adapt to changing climates.

The period when the Neanderthals went extinct saw severe and rapid climate fluctuations, with cold, dry periods alternating with warmer, wetter periods.

These fluctuations could have disrupted the ecosystems that the Neanderthals relied on, making it harder for them to find food and other resources.

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

As modern humans migrated out of Africa, they may have carried with them pathogens to which the Neanderthals had no immunity.

This 'disease hypothesis' is still speculative, but it is supported by the fact that contact between human populations has often resulted in the spread of diseases.

One of the most fascinating 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, providing groundbreaking insights into the genetic relationship between Neanderthals and modern humans.

It discovered that modern humans outside of Africa carry about 1.8 to 2.6% Neanderthal DNA in their genomes.

This is the result of interbreeding between the two species, which likely occurred in the Middle East, shortly after Homo sapiens left Africa, and possibly also later in Europe.

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

Instead, it is found in specific regions, suggesting that some Neanderthal genes were beneficial and were selected for over time.

These genes are associated with a variety of traits, including skin and hair color, immune response, and even neurological traits.

For example, some variants of the MC1R gene, which is involved in skin and hair pigmentation, are thought to have been inherited 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 are notably devoid of Neanderthal DNA.

These 'deserts' of Neanderthal ancestry may represent regions where Neanderthal genes were detrimental and were selected against.

For example, genes involved in male fertility are notably lacking 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 implications for 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 complex web of interconnections.

It also challenges the traditional view of Neanderthals as a separate, primitive species, and instead paints a picture of Neanderthals as our close relatives, with whom we shared a common history and a common genetic heritage.