Neanderthals 101 | National Geographic

• [Narrator] Neanderthals are often depicted as brutish cave men, but science shows that our early ancestors were actually quite advanced. Neanderthals, or homo neanderthalensis, are our closest relatives in the human family tree. The species lived from about 400,000 to 40,000 years ago and inhabited an area that stretched as far as Europe's Atlantic coast and as far east as central Asia. Their habitat reached northward to modern day Belgium, making them the first humans to survive a cold, glacial ecosystem.

The north's cold environment may have influenced neanderthals' physique. Their bodies were relatively short, with males averaging five feet, five inches and females five feet, one inch tall, and they were stocky with broad chests, bulky torsos, and muscular limbs. These adaptations helped neanderthals generate and retain body heat. Also, their noses were large and had relatively high bridges. This created a nasal chamber that warmed and humidified the cold, dry air they'd breathe in northern regions.

Apart from adaptations that helped neanderthals survive a harsh, wintry habitat, the species also developed large brains. They were similar in size to modern humans' brains and were often larger. An increase in brain size may have played a significant role in another type of adaptation, culture. Culture is indicative of an intelligent species, and archeological evidence suggests that neanderthals had a relatively sophisticated culture. They built shelters, made and wore clothing, and created advanced tools.

In fact, they were the first human species to make tools out of bone, not just stone. They also created objects that served ornamental purposes. Neanderthals are suspected to be the first humans to carry out the symbolic gesture of burying their dead and adorning grave sites with flowers. Neanderthals may have also created what may be the world's oldest cave art, which was found in Spain.

Despite advances in their culture, sometime after 40,000 years ago, neanderthals mysteriously disappeared. Some scientists believe the neanderthals were killed or outcompeted by modern humans, or homo sapiens, who arrived in Europe at around the same time as the neanderthals' extinction. However, another theory suggests that neanderthals mated with modern humans and were absorbed into the humans' much larger population. That may explain why most people of European or Asian descent have 1% to 2% neanderthal genes in their DNA.

For more than 150 years, neanderthals have perplexed anthropologists. The first neanderthal fossil specimen was discovered in Belgium in 1829 by Philippe-Charles Schmerling. However, it wasn't officially classified as neanderthal until decades later. The first fossil to be recognized as neanderthal and as an early human or genus homo fossil was found in 1856 by quarrymen in Germany. The new species was named neanderthalensis after the area where the fossils were found, Neander Valley.

Neanderthals' fossils tell us how evolution built them to be sturdy, to survive their harsh environment, but their tools, art, and DNA tell us that their resilience also involved innovation, creativity, and social behavior, much like homo sapiens today.