Humans Faced Extinction in Middle Palaeolithic Era

An extensive study into genetics has revealed that humans could have potentially become extinct some 70, 000 years ago. Scientific analysis has made apparent that the numbers of our predecessors on a global basis may have at one point in the Middle Palaeolithic era (between 200, 000- 35, 000 years ago) plummeted to a mere 2000 individuals, prior to growing again in the beginning of the Stone Age. This finding came about through the Genographic Project, an investigation that was launched in 2005 with the aim of using genetics to gain a broader understanding of anthropology.

The project’s director Spencer Wells of the National Geographic Society remarked,

”This study illustrates the extraordinary power of genetics to reveal insights into some of the key events in our species' history. Tiny bands of early humans, forced apart by harsh environmental conditions, coming back from the brink to reunite and populate the world. Truly an epic drama, written in our DNA."

The study incorporated findings from previous investigations which, through the analysis of mitochondrial DNA that is passed onto offspring through their mothers, concluded that a maternal ancestor to all modern human beings lived in Africa about 200, 000 years ago. This new study examined the mitochondrial DNA of the Khoi and San people in South Africa who are believed to have diverged evolutionarily from other people between 90,000 and 150,000 years ago. It was concluded from this study that humans divided into smaller populations prior to the Stone Age, and then later rejoined as a single population to repopulate the Earth and spread out to other areas.

Scientists postulate that a climatological shift, namely the series of severe droughts that hit Eastern Africa between 135, 000 and 90, 000 years ago, most probably effected these population changes, and may have led the human beings to move away from one another into smaller groups. An adviser from the Genographic Project, Paleontologist Meave Leakey, said: "Who would have thought that as recently as 70,000 years ago, extremes of climate had reduced our population to such small numbers that we were on the very edge of extinction."

The resilience of human beings at this time stands testament to our highly adaptable DNA. According to current figures held by the US Census Bureau, today more than 6.6 billion people inhabit the planet.

Anna Erian

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Picture taken from http://www.lbl.gov/Science-Articles/Archive/Genomics-Neanderthal.html
Information Sourced from http://www.news.com.au/couriermail/story/0,23739,23594665-952,00.html