Geography predicts neutral genetic diversity of human populations

A leading theory for the origin of modern humans, the ‘recent African origin’ (RAO) model 1], postulates that the ancestors of all modern humans originated in East Africa and that, around 100,000 years ago, some modern humans left the African continent and subsequently colonised the entire world, displacing previously established human species such as Neanderthals in Europe 2., 3.. This scenario is supported by the observation that human populations from Africa are genetically the most diverse 2] and that the genetic diversity of non-African populations is negatively correlated with their genetic differentiation towards populations from Africa 3].