A note on Nuba Mountain verb extensions

Based on the available literature and personal communications with specialists, this paper surveys the rich occurrence of verb extensions in the Nuba mountain languages which mark different grammatical functions such as causative, dative and locative applicatives, comparative, passive, antipassive, reciprocal/reflexive, and associative/instrumental, as well as ventive, itive, habitual, iterative and pluractional marking. Given the diversity of forms among the different groups in the area, a set of guidelines is considered to determine whether specific extensions can be reconstructed or are recent innovations. An extensive table is provided which provides the forms of the reported extensions and compares them with those reconstructed in specific subbranches of Niger-Congo, Nilo-Saharan, Afro-Asiatic, and in Khoe.