the same genetic experiment (which wrote the American
Journal of Human dzhinetiks "), the researchers concluded that the African
man first walked around the same time - 70,000 years ago.



Small differences



Unlike their closest relatives - chimps - all humans have
virtually identical DNA. Moreover, even in a group of individual chimpanzees
individuals havemoredifferences in the stascture of DNA, than all 6 billion people,
now living on Earth.



Scientists believe that 5-6 million years ago, a man separated from his ancestor (the total
with chimpanzees), and during this time, homo sapiens was bound to develop
internal genetic differences. A lack thereof suggests
that the genetic composition of man was visibly narrowed recently (in
historical sense, of course), and it was then erased earlier
genetic variation.



The oldest member



Because the DNA in all humans is almost identical, the researchers began looking
differences at least at the level of generations. One of the methods they used,
involves the study of so-called microsatellites - short
repetitive segments of DNA, distinct from generation to generation.



Scientists from Stanford University and the American, Russian Academy of Sciences
compared 377 microsatellite markers in DNA collected from 52 regions of the Earth. In
result revealed a close relationship of two generations of hunters and gatherers
living in sub-Saharan Africa - Pygmies Mbuti living in the Congo basin, and
hozianov Bushmen in Botswana.



Researchers believe that the Mbuti and hoziany - representatives of the oldest branches
modern humans from all studied.



In addition, the study found that the division between hunter-gatherers and
farmers in Africa occurred 70-140 thousand years ago, and after that could
place migration of modern humans from Africa. Of earlier
genetic research - the study of chromosome-Y, taken frommorethan a thousand
men, representing 21 generations - has led scientists to conclude that
the first man left Africa about 66,000 years ago.



But such small differences in the DNA of modern humans indicates that in the past
100 thousand years a person is literally on the verge of extinction, and all the inhabitants
Now representatives of the human race - the descendants of a small group of surviving
time. Its population probably does not exceed a critical period of 2 thousand
individuals.

Source: News.bbc.co.uk