Modern humans originated from a single area in Sub-Saharan Africa

A new study by British researchers has proved the theory of single origin of humans in Africa.

Washington, July 19 : A new study by British researchers has proved the theory of single origin of humans in Africa.

The researchers combined studies of global genetic variations in humans with measurements of 6000 human skulls from across the world in academic collections to reveal that genetic diversity decreased in populations the further away from Africa they were - a result of 'bottlenecks' or events that temporarily reduced populations during human migration.

"The origin of anatomically modern humans has been the focus of much heated debate. Our genetic research shows the further modern humans have migrated from Africa the more genetic diversity has been lost within a population," said Lead researcher, Dr Andrea Manica from the University of Cambridge's Department of Zoology.

"However, some have used skull data to argue that modern humans originated in multiple spots around the world. We have combined our genetic data with new measurements of a large sample of skulls to show definitively that modern humans originated from a single area in Sub-saharan Africa," he said.

Competing theories on the origins of anatomically modern humans claim that either humans originated from a single point in Africa and migrated across the world, or that different populations independently evolved from homo erectus to home sapiens in different areas.

Further study of an exceptionally large sample of human skull revealed that not only was variation highest amongst the sample from south eastern Africa, but that it did decrease at the same rate as the genetic data the further the skull was away from Africa.

To ensure the validity of their single origin evidence, the researchers also attempted to use their data to find non-African origins for modern humans.

"To test the alternative theory for the origin of modern humans we tried to find an additional, non-African origin. We found this just did not work. Our findings show that humans originated in a single area in Sub-Saharan Africa," said Dr Francois Balloux.

The findings appear in the July 19 issue of Nature.

ANI