Language change in small-scale multilingual societies: Trees, waves, and magnets?

The tree and wave models of linguistic diversification represent the most longstanding approaches to understanding the ways in which linguistic subgroups develop. Such highly schematic scenarios, however, lack the sociolinguistic grounding that would be needed to fully understand the range of historical processes that trigger the formation of new subgroups, and there is evidence that tree-like patterns of linguistic diversification may be associated with radically different underlying sociohistories. This chapter proposes a new historical path to the development of tree-like patterns through changes initiated and reinforced by what will be termed magnetic sociolinguistic dynamics. Support for this proposal is drawn from languages spoken by small-scale societies in a rural African region, a sociolinguistic context which has not received significant attention in the literature on linguistic diversification, even though it is likely historically typical for many parts of Africa and beyond.