Mankinds Extinction..., Almost

As recent as 70,000 years ago mankind almost became extinct. The world population was reduced to a mere 2000 individuals. The remarkable recovery from this minimal population size seems to indicate that mankind has the ability to survive catastrophic events that bring us to the brink of extinction.

This was the late stone age and man was still confined to Africa. The whole region was subject to a series of severe droughts between 135,000 and 90,000 years ago and this climatological shift may have contributed to the population decline and subsequent division into small, isolated groups each of which had an independent destiny. It is believed that humans were split into two species, one in East Africa, the other in South Africa.

The isolated African groups started to meet up again with each other about 40,000 years ago, during the African Late Stone Age, and then grew in numbers and moved to an expanding area. Many archeologists believe this era heralded the beginning of fully modern human behavior, including abstract thought and complex spoken language. The big surprise was the length of time the populations were separate - as much as half of our entire history as a species.

This new genetic study conducted by the Genographic Project, published in the American Journal of Human Genetics on April 24, 2008 concludes that these disparate groups were probably forced apart by the drought conditions and as the droughts subsided, the groups then came together again, before man expanded out of Africa, to populate the globe.

Amazingly, this information is locked within the human DNA and reveals human history through the ages. This latest research project was started in 2005 to study anthropology using genetics. Specifically, this study used the mitochondrial DNA of the Khoi and San people in South Africa. The mitochondrial DNA is passed solely from mothers to offspring.

The original pioneering research using mitochondrial DNA was the epic making 1980 study by Wesley Brown, then at the University of California at Berkeley, which traced modern humans to a single "mitochondrial Eve," who lived in Africa between what the researchers estimated as between 140,000 and 290,000 years ago. This study found unexpectedly small differences among the mitochondrial DNA, signifying a relatively recent origin for modern humans. Brown's data suggested it would take 180,000 to 360,000 years to produce today's diversity starting from a single Eve.