Two potential migratory routes followed by modern humans to colonize Eurasia from Africa have been proposed. These are the two natural passageways that connect both continents: the northern route through the Sinai Peninsula and the southern route across the Bab al Mandab strait. Recent archaeological and genetic evidence have favored a unique southern coastal route. Under this scenario, the study of the population genetic structure of the Arabian Peninsula, the first step out of Africa, to search for primary genetic links between Africa and Eurasia, is crucial. The haploid and maternally inherited mitochondrial DNA (mtDNA) molecule has been the most used genetic marker to identify and to relate lineages with clear geographic origins, as the African Ls and the Eurasian M and N that have a common root with the Africans L3.
Phylogeographic Analysis of Haplogroup E3b (E-M215) Y Chromosomes Reveals Multiple Migratory Events Within and Out Of Africa
We explored the phylogeography of human Y-chromosomal haplogroup E3b by analyzing 3,401 individuals from five continents. Our data refine the phylogeny of the entire haplogroup, which appears as a collection of lineages with very different evolutionary histories, and reveal signatures of several distinct processes of migrations and/or recurrent gene flow that occurred in Africa and western Eurasia
The out-of-Africa model of anatomically modern human evolution posits an African origin 100,000 - 200,000 years ago, followed by subsequent dispersal(s) to Eurasia and other continents within the last 100,000 years (Stringer and Andrews 1988). Although alternative models have been proposed, the out-of-Africa scenario receives the most support both from archeological and genetic evidence (Lahr and Foley 1994). However, the route(s) followed by the African migrants remain poorly understood...