Focalisation and defocalisation in Isu

Information structure in Isu is encoded by a variety of morphosyntactic strategies, involving markers of focalisation and defocalisation, both interacting with a syntactic pattern where the relative position vis-à-vis the finite verb plays a crucial role. In most of its properties, the Isu system closely parallels the one found in Aghem. However, there are some differences relating to form and distribution of defocalising enclitic markers on nouns. This opens a low-level diachronic perspective on the phenomenon and illustrates intermediary stages of a pragmatico-syntactically motivated transition from an earlier prefix marking system of noun classes towards a system in which prefixes fade out and noun classes come to be predominantly marked by enclitics which have not (yet) made it to suffixes.