No nearer to reasons for Neanderthals' extinction

By Michael Evans - 10 Jan 2011 11:47:58 GMT
No nearer to reasons for Neanderthals' extinction

Neanderthals get their name from the Neander Valley in Germany where their first remains were discovered in the mid-19thcentury. They are usually regarded as mankind's immediate predecessors.

Archaeologists cannot agree whether Neanderthals are a separate human species or a subspecies of modern humans. Some say that they first began to appear as long as 600,000 years ago, but they were certainly around when our direct ancestors, Homo sapiens began to arrive.

For about 10,000 years the two groups coexisted and there is some evidence to suggest interbreeding took place, particularly in the Middle East where it is said that between 1% and 4% of the DNA of Eurasian people was contributed by Neanderthals.

But no definite Neanderthal specimens have been found that are younger than 25,000 to 30,000 years so it can only be assumed that they suddenly died out at around that time.

There have been many theories as to why this happened. One theory is that it was a result of interbreeding with Homo sapiens and they just simply disappeared through absorption. An alternative theory is that the extinction was as a result of an early example of genocide when the advancing Homo sapiens moved into their established habitat and simply drove them out in a scenario of violent conflict.

Yet another theory puts the blame on climate change. We know that about 55,000 years ago the weather began a series of wild fluctuations, from extreme cold conditions to mild cold and back again in a matter of a few decades. These fluctuations peaked about 30,000 years ago and the theory is that with such rapid changes in the weather pattern, which in turn produced changes in plant and animal life, the Neanderthal simple couldn't cope, causing large numbers to die.

However, researchers from the George Washington University and the Smithsonian Institution have discovered evidence that counters the argument that Neanderthals disappeared as a result of deficiencies of diet.

Lead researcher Dr Amanda Henry from GWU said that although Neanderthals have traditionally been portrayed as backward and primitive, we are now beginning to realise that they had some quite advanced technologies and behaviours. Studies have been carried out on Neanderthal teeth and the discovery of starch granules has proved that they made sophisticated and thoughtful food choices.

Previously it was considered that a major contributory factor in the demise of Neanderthals was that with a diet solely dependent on meat, during the major climate changes they simply could not compete against the omnivorous Homo sapiens. But Dr Henry and her fellow researchers have discovered that nutrient-rich plants such as date palms, legumes and grains such as barley were a regular part of their diet.

The researchers discovered by analysing starch granules in the dental calculus of the fossilised teeth that in addition to the Neanderthal diet being very similar to that of the Homo sapiens, they actually prepared and cooked their food to make it taste better and easier to digest.

So, we are still no nearer in discovering the cause of the Neanderthal demise.