title: Migration and interaction in a contact zone: mtDNA variation among Bantu-speakers in Southern Africa.
abstract: Bantu speech communities expanded over large parts of sub-Saharan Africa within the last 4000-5000 years, reaching different parts of southern Africa 1200-2000 years ago. The Bantu languages subdivide in several major branches, with languages belonging to the Eastern and Western Bantu branches spreading over large parts of Central, Eastern, and Southern Africa. There is still debate whether this linguistic divide is correlated with a genetic distinction between Eastern and Western Bantu speakers. During their expansion, Bantu speakers would have come into contact with diverse local populations, such as the Khoisan hunter-gatherers and pastoralists of southern Africa, with whom they may have intermarried. In this study, we analyze complete mtDNA genome sequences from over 900 Bantu-speaking individuals from Angola, Zambia, Namibia, and Botswana to investigate the demographic processes at play during the last stages of the Bantu expansion. Our results show that most of these Bantu-speaking populations are genetically very homogenous, with no genetic division between speakers of Eastern and Western Bantu languages. Most of the mtDNA diversity in our dataset is due to different degrees of admixture with autochthonous populations. Only the pastoralist Himba and Herero stand out due to high frequencies of particular L3f and L3d lineages; the latter are also found in the neighboring Damara, who speak a Khoisan language and were foragers and small-stock herders. In contrast, the close cultural and linguistic relatives of the Herero and Himba, the Kuvale, are genetically similar to other Bantu-speakers. Nevertheless, as demonstrated by resampling tests, the genetic divergence of Herero, Himba, and Kuvale is compatible with a common shared ancestry with high levels of drift, while the similarity of the Herero, Himba, and Damara probably reflects admixture, as also suggested by linguistic analyses.
authors.affiliation: Department of Evolutionary Genetics, MPI for Evolutionary Anthropology, Leipzig, Germany; Department of Biological, Geological and Environmental Sciences, Laboratory of Molecular Anthropology, University of Bologna, Bologna, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Barbieri
authors.affiliation: CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos da Universidade do Porto, Vairão, Portugal; STAB VIDA, Investigação e Serviços em Ciências Biológicas, Lda, Oeiras, Portugal.
authors.forename: Mário
authors.initials: M
authors.lastname: Vicente
authors.affiliation: CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos da Universidade do Porto, Vairão, Portugal; Departamento de Biologia, Faculdade de Ciências da Universidade do Porto, Porto, Portugal.
authors.forename: Sandra
authors.initials: S
authors.lastname: Oliveira
authors.affiliation: Department of African Languages and Cultures, Ghent University, KongoKing Research Group, Ghent, Belgium; Université libre de Bruxelles, Faculté de Philosophie et Lettres, Brussels, Belgium.
authors.forename: Koen
authors.initials: K
authors.lastname: Bostoen
authors.affiliation: CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos da Universidade do Porto, Vairão, Portugal; Departamento de Biologia, Faculdade de Ciências da Universidade do Porto, Porto, Portugal.
authors.forename: Jorge
authors.initials: J
authors.lastname: Rocha
authors.affiliation: Department of Evolutionary Genetics, MPI for Evolutionary Anthropology, Leipzig, Germany.
authors.forename: Mark
authors.initials: M
authors.lastname: Stoneking
authors.affiliation: Laboratoire Dynamique du Langage, UMR5596, CNRS and Université Lyon Lumière 2, Lyon, France.
authors.forename: Brigitte
authors.initials: B
authors.lastname: Pakendorf
mesh_terms: D017954:Africa South of the Sahara; D044383:Black People / Q000235:genetics*; D004272:DNA, Mitochondrial / Q000145:classification / Q000235:genetics*; D003710:Demography; D004641:Emigration and Immigration; D014644:Genetic Variation; D005828:Genetics, Population; D006239:Haplotypes; D006801:Humans; D007802:Language; D010802:Phylogeny; D017422:Sequence Analysis, DNA
chemical_list: D004272:DNA, Mitochondrial