Wednesday, January 6, 2010
What happened to the Neanderthals?
(Left, an illustration of Neanderthal man from Cell, Vol. 90, July 11,1997; above, a model head of Neanderthal man created by Maurice Wilson of the Natural History Museum, London.)
The first fairly complete Neanderthal skeleton was found in 1856 in Germany (in the Neandertal Valley, hence their name). Their remains have since been found in caves all over Europe, and as far East as Central Asia.
One of the great unsolved mysteries is why the Neanderthals disappeared roughly 30,000 years ago. Were they killed by marauding Cro Magnons (modern humans)? Did they simply starve because of dwindling resources caused by the encroaching Ice Age? Or did they interbreed with and become absorbed by the Cro Magnons?
The fossil evidence is inconclusive. A cave in Portugal yielded some Cro Magnon skeletons with "Neanderthal traits" from roughly 24,500 years ago; these have been used as proof of the admixture theory. On the other hand, recent mitochondrial DNA studies indicate that Neanderthals were a separate species, and there was no intermixing. (Their mitochondrial DNA does not show up in modern man.) But mitochondrial DNA has a strictly matrilineal descent, and is not conclusive. What scientists are fairly certain of is that Neanderthals and modern humans shared 99.5% of their DNA, the two had a common ancestor, and they probably diverged around 4-500,000 years ago.
The word "Neanderthal" has long been synonymous with brutishness. But the Neanderthals buried their dead and cared for their sick. (Skeletal evidence of Neanderthals with otherwise mortal injuries who survived long after being hurt indicates that the Neanderthals cared for their sick.)
Their skulls -- and therefore cranial capacity -- were as large as ours at birth and larger in adulthood. They were also much stronger than us; this is apparent from their thicker bones and larger muscle attachments. The workers who first dug up the skeleton in the Neandertal Valley first thought they had unearthed the remains of a bear. They averaged around five and a half feet in height, the same as Cro Magnons of the era. They also had wider shoulders, deeper chests, shorter upper arms, and forearm bones which were actually bowed by their forearm muscles.
(In other words, they were incredibly studly, like the fellow at top left.)
Facially, they were distinguished by their prominent brow ridges, recessive chins, and protuberant noses.
I once read that if you had these characteristics, it meant that you might have Neanderthal ancestry. I'd like to believe this is so.
It's interesting to speculate on what the interactions between Neanderthals and Cro Magnon were. Each group undoubtedly regarded the other as supremely ugly and subhuman. Eventually the Cro Magnons triumphed; it is commonly assumed that this was because of superior brainpower. But might it have been a case of the Cro Magnons triumphing because of treachery? Is it possible that they merely had more low animal cunning and were somehow able to trick the more noble (and trusting) Neanderthals?
Sorta like the Cro Magnons vs. the Na'vi in Avatar?