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View Full Version : A little Neanderthal in most of us...



June Pelo
07-05-10, 17:51
Scientists have discovered that modern human beings interbred with Neanderthals tens of thousands of years ago and that 1 to 4% of the genes carried by non-African people are traceable to the cavemen, according to the Neanderthal Project. The findings show that modern humans and Neanderthals, known to occupy the same parts of Europe shortly before the Neanderthals disappeared, interbred someplace inthe Middle East about 80,000 years ago. The interbreeding occurred after modern humans left Africa but before they diversified into the ethnic groups that exist today. That's why northern Europeans, the Chinese and Papua New Guineans carry traces of Neanderthal genes, but Africans do not.

The Neanderthal genes were recovered from three bones excavated in a cave in Croatia about 20 years ago. One is 38,000 years old, another 44,000 years old and one is undated. They appear to be shin bones and all are from females. Proto-humans and chimpanzees diverged from each other about 6.5 million years ago. Modern humans and Neanderthals diverged about 825,000 years ago. On a genetic level, Neanderthals and modern humans are almost as closely related as today's ethnic groups are to each other.

The researchers identified 73 genes for which all modern people have the same molecular version but for which Neanderthals have the more ancient, chimpanzee version. In five of the genes, there are two molecular differences between the human and Neanderthal-and-chimpanzee versions, suggesting there may be an especially important difference in the human version. One gene encodes a protein that helps the sperm cell's flagellum beat. Another is for a protein that seems to be involved in healing of wounds. A third is for a protein abundant in skin, sweat glands and hair roots.

Whether evolutionary changes in those three genes - or in dozens of others showing hints of natural selection - proved especially beneficial in Homo sapiens' competition with other hominins isn't known. The new research suggests they might be, and evoutionary biologists will be looking at them for further evidence they may hold part of the answer of what makes human beings human.

Los Angeles Times and The Washington Post

sune
17-05-10, 07:57
Now there is something for the conservapedia people to chew. Once I saw a comic strip where a shocked chimp read a book and said to his mates: "Oh how terrible; we have developed from the conservatives in the American Mid-West." :D

Sune