title: The dawn of human matrilineal diversity.
abstract: The quest to explain demographic history during the early part of human evolution has been limited because of the scarce paleoanthropological record from the Middle Stone Age. To shed light on the structure of the mitochondrial DNA (mtDNA) phylogeny at the dawn of Homo sapiens, we constructed a matrilineal tree composed of 624 complete mtDNA genomes from sub-Saharan Hg L lineages. We paid particular attention to the Khoi and San (Khoisan) people of South Africa because they are considered to be a unique relic of hunter-gatherer lifestyle and to carry paternal and maternal lineages belonging to the deepest clades known among modern humans. Both the tree phylogeny and coalescence calculations suggest that Khoisan matrilineal ancestry diverged from the rest of the human mtDNA pool 90,000-150,000 years before present (ybp) and that at least five additional, currently extant maternal lineages existed during this period in parallel. Furthermore, we estimate that a minimum of 40 other evolutionarily successful lineages flourished in sub-Saharan Africa during the period of modern human dispersal out of Africa approximately 60,000-70,000 ybp. Only much later, at the beginning of the Late Stone Age, about 40,000 ybp, did introgression of additional lineages occur into the Khoisan mtDNA pool. This process was further accelerated during the recent Bantu expansions. Our results suggest that the early settlement of humans in Africa was already matrilineally structured and involved small, separately evolving isolated populations.
authors.affiliation: Molecular Medicine Laboratory, Rambam Health Care Campus, Haifa 31096, Israel. behardm@usernet.com
authors.forename: Doron M
authors.initials: DM
authors.lastname: Behar
authors.forename: Richard
authors.initials: R
authors.lastname: Villems
authors.forename: Himla
authors.initials: H
authors.lastname: Soodyall
authors.forename: Jason
authors.initials: J
authors.lastname: Blue-Smith
authors.forename: Luisa
authors.initials: L
authors.lastname: Pereira
authors.forename: Ene
authors.initials: E
authors.lastname: Metspalu
authors.forename: Rosaria
authors.initials: R
authors.lastname: Scozzari
authors.forename: Heeran
authors.initials: H
authors.lastname: Makkan
authors.forename: Shay
authors.initials: S
authors.lastname: Tzur
authors.forename: David
authors.initials: D
authors.lastname: Comas
authors.forename: Jaume
authors.initials: J
authors.lastname: Bertranpetit
authors.forename: Lluis
authors.initials: L
authors.lastname: Quintana-Murci
authors.forename: Chris
authors.initials: C
authors.lastname: Tyler-Smith
authors.forename: R Spencer
authors.initials: RS
authors.lastname: Wells
authors.forename: Saharon
authors.initials: S
authors.lastname: Rosset
mesh_terms: D004272:DNA, Mitochondrial / Q000235:genetics*; D019143:Evolution, Molecular; D014644:Genetic Variation; D005828:Genetics, Population; D006239:Haplotypes; D006801:Humans; D008957:Models, Genetic; D008969:Molecular Sequence Data; D010802:Phylogeny
chemical_list: D004272:DNA, Mitochondrial