Divergence and contact in Southern Bantu language and population history

In this paper we present a new, lexicon-based phylogeny of 34 Southern Bantu languages, and combine it with previous insights from linguistics, archaeology, and genetics to study the history of Southern Bantu languages and their speakers. Our phylogeny shows all Southern Bantu languages to derive from a single, direct ancestor, which contrasts with archaeological evidence indicating separate migrations of Bantu speakers into southern Africa. This suggests that the Bantu languages spoken by the first migrants became extinct, and the ancestor of present-day Southern Bantu languages only emerged in southern Africa during the second millennium CE. We also map the distribution of previously established or suspected Khoisan-derived linguistic features in Southern Bantu languages onto this phylogeny. Evidence for intensive contact with speakers of Khoisan languages also comes from population genetics, which shows that Khoisan linguistic influence is mainly seen in languages spoken by populations displaying a higher degree of genetic admixture.