Neanderthaler

In 1856 a skeleton was found in the Feldhofer Grotto near Düsseldorf, which caused a stir in the scientific world and fuelled the debate about human evolution. The depiction of Neanderthals as primitive, club-wielding cave dwellers was widespread for a long time, but new research paints a more differentiated picture.
The Neanderthal man was a cultural being, widespread throughout Eurasia and successfully lived through warm and cold periods for 200,000 years.

• Short, strong and curved limb bones with massive joints and large muscle attachments
• Very long collarbones indicate broad shoulders
• Large brain with strong over-eye bulges and low forehead, strong masticatory apparatus and receding chin

New sequencing and analysis methods enable us to analyse the DNA of long-extinct organisms. This old DNA is often badly damaged and affected by bacteria and environmental influences.
In 2010, the genome of the Neanderthal man was completely decoded. This led to the important realisation that modern humans (Homo sapiens) and Neanderthals interbred. These genetic traces can still be found today in the genomes of all populations outside Africa, which contain around 1.5 to 2.1 % Neanderthal DNA.
There is evidence that the first genetic exchange between modern humans and Neanderthals took place around 200,000 years ago in western Asia, followed by another wave around 100,000 years ago. However, the main mixing occurred later, around 50,000 to 60,000 years ago, in Europe and Asia.

While some Neanderthal genes may have provided benefits, there are also genetic components that pose health challenges.

• In particular, genes involved in the defence against diseases and infections originate from Neanderthals. For example TLR1, TLR6, and TLR10 (Toll-like receptors), which help the body to react to bacterial infections and produce a higher immunity against certain pathogens. However, these genes could also increase the risk of autoimmune diseases such as lupus and Crohn's disease, as it is easier for the immune system to overreact.
• Several Neanderthal genes influence skin pigmentation and hair density. Variants in the BNC2 gene, for example, influence skin pigmentation and may have helped Neanderthals to produce vitamin D more efficiently in the less sunny regions of Eurasia.
• Certain Neanderthal genes that are responsible for fat metabolism are also still found in Homo sapiens. These genes influence how the body stores fats and processes energy. A Neanderthal variant in the GLP1R gene is associated with the regulation of blood sugar levels and possibly also with a tendency to diabetes.
• Some genetic variants originating from Neanderthals could also influence fertility. The ADAMTSL3 gene, for example, is associated with an increase in fertility in modern humans.
• Neanderthal variants in genes such as FOXP2, which is important for the ability to speak, are present in modern humans. However, their influence on the ability to speak is not yet fully understood.
• Some Neanderthal genes are associated with an increased risk of depression and other mental illnesses. Variants in the NOV gene are also relevant here and could play a role in cognitive processing.
• A variant in chromosome 3 (gene cluster) has shown that people with certain Neanderthal genes could have a higher risk of severe courses of COVID-19 infection.

Worth mentioning in this context are the Denisova people, a small group of early hominins closely related to the Neanderthals. This population is known from finds from the Denisova Cave in the Altai Mountains of Siberia and from the Baishiya Cave in Tibet.
Populations in Papua New Guinea and Southeast Asia carry the Denisova human genome.  As with Neanderthals, certain Denisova gene variants confer an advantage on the populations that carry them. One gene variant, for example, is responsible for the improved physiological adaptation to high altitudes of some Tibetan populations.

The distribution of Neanderthals (Homo neanderthalensis) covered a large part of Europe and western Asia. Their remains have been found in various regions, which indicates their adaptability and mobility.
Archaeological finds, such as tools or remains of Neanderthals, show that Neanderthals reached as far north as northern Germany during warmer periods (100,000 to 120,000 years ago), and possibly even further north.
During these periods, they were heavily dependent on hunting large animals such as European forest elephants, as bone finds with clear cutting patterns in Neumark-Nord (DE) suggest.
 
Many Neanderthal fossils have been found in southern regions such as El Sidrón in Spain, Gibraltar, Krapina, Croatia and Shanidar in Iraq. These finds show that Neanderthals lived in different environments and adapted to different climatic conditions.

Neanderthals became extinct around 30,000 years ago. The reasons for this have not yet been clarified, although a combination of several causes currently appears to be the most plausible.

• Small population size: Neanderthal populations consisted of only a few individuals during their entire lifetime. In addition, the populations were mostly isolated from each other, especially during the cold periods. Such populations are fragile and have difficulty recovering after changes.  
• Higher mortality rate: If Neanderthals generally had a higher mortality rate than Homo sapiens, they would die out quickly (within 1'000 years).
• Niche too full: Homo sapiens spread rapidly across the continent. The niche previously occupied by Neanderthals alone now had to suffice for another species. Competition for resources increased.

The Neanderthals were mainly hunters who mostly hunted medium-sized animals and organised their lives according to the migrations of the animal herds. They often camped in the open at water sources and on slopes. Caves and abris were only used for short stays. They had their own tool culture, the Mousterian, with complex techniques such as the Levallois method for producing efficient stone tools.
Jewellery and simple cave paintings indicate that Neanderthals also possessed symbolic thinking.
Evidence of injuries and diseases, finds of old individuals and evidence of burials suggest that Neanderthals lived in a social community and cared for its members.