Regarding the genetic data;Y chromosome and mtDNA markers are sex-linked and therefore can be lost over generations,for example:I have no Y chromosome nor mtDNA from either my maternal Grandfather nor paternal Grandmother..does this mean I'm not related to half my set of Grandparents?!
Maybe the genetic evidence suggests that Africa has had a larger and more stable population level over time and,(with the entire human species being an interconnected and interbreeding network spanning the old world) the African lineages have tended to 'edge out' the others in the genetic record.
posted by Robert Browne
August 5, 2009
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