T Tel Aviv, May 17 : A mathematician from the Tel Aviv University has claimed that the human race was genetically divided into two separate groups within Africa for as much as 100,000 years, which is roughly half of its existence.
  This theory was put forward by Dr. Saharon Rosset from the School of Mathematical Sciences at Tel Aviv University, who worked along with team leader Doron Behar from the Rambam Medical Center to analyze African DNA. Their goal was to study obscure population patterns from hundreds of thousands of years ago. "We wanted to look into the ancient history of our species. How did we live throughout most of our existence as a species? Did we live as one - or were we fractured into small groups? Until now, it wasn't really clear," said Rosset. Researchers believe that about 60,000 years ago, modern humans started their epic journeys to populate the world. This time period has been the primary focus of anthropological genetic research. However, relatively little is known about the demographic history of our species over the previous 140,000 years in Africa. The current study returns the focus to Africa and thereby refines the understanding of early modern Homo sapiens history. According to Rosset, the study provides insight into the early demographic history of human populations before they moved out of Africa. "These early human populations were small and isolated from each other for many tens of thousands of years," she said. The team's research was based on a survey of African mitochondrial DNA (mtDNA) and is the most extensive survey of its kind. It included over 600 complete mtDNA genomes from indigenous populations across the continent. Recent data suggests that Eastern Africa went through a series of massive droughts between 90,000 and 135,000 years ago. It is possible that this climate shift contributed to the population splits. But, what is surprising is the length of time the populations were separate - for as much as half of our entire history as a species. According to Dr. Spencer Wells, director of the Genographic Project and Explorer-in-Residence at the National Geographic Society, "This new 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," he added. (ANI) © 2007 ANI TAGS: Science 
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