The dispersal of Bantu-speaking people from their ancestral homeland in the borderland between current-day Nigeria and Cameroon across most of Central, Eastern, and Southern Africa had a significant impact on the languages, cultures, and demography of autochthonous populations. Inversely, foragers and pastoralists also considerably contributed to the gene pool of Bantu-speaking communities, the speciation of their languages, and the evolution of their cultures. In this chapter, the impact of indigenous languages on Bantu language variation is assessed by comparing the language contact situations in Southern and Central Africa. Southern Africa is much better documented, because the much shallower time depth of contact between Bantu-speaking newcomers and autochthonous populations allowed the latter to survive as separate populations, often maintaining a language unrelated to Bantu. In Central Africa, the dispersal of Bantu languages is much older. Together with the success of other families, such as Ubangi and Central-Sudanic, it led to the death of all languages previously spoken by rainforest hunter-gatherers. Still little is therefore known about prehistoric language contact between indigenous forest foragers and immigrant communities. Nonetheless, Southern Africa provides us with useful insights to be tested in Central Africa.

Chapter 5 explores the implications of the Laryngeal Articulator Model for phonology and the place of voice quality in phonological analysis. The Phonological Potentials Model (PPM) is explained, and synergistic and anti-synergistic relations are mapped in diagrams. Earlier phonological approaches that do not consider the laryngeal articulator are reviewed, while the PPM demonstrates how cooperative lingual-laryngeal activity can be accommodated in phonological analysis. Case studies of languages having lower-vocal-tract contrasts (vocal register, pharyngealization in click languages) give an idea of the network of articulatory relationships that form the grounding of phonological representations. We highlight vocalic-harmony (so-called [ATR]), syllabic, and tense–lax registers in West African, Northeast African and Southeast Asian languages. The case of Southern Wakashan pharyngeal genesis illustrates the role of voice quality in sound change.