Roland Pfau and Markus Steinbach
This article considers the factors and processes associated with grammaticalisation in sign languages. It provides commentaries on the methodological challenges diachronic sign language research is faced with and describes selected grammaticalisation phenomena that we take to be modality-independent. It also discusses modality-specific instances of grammaticalisation and the grammaticalisation of gestures. The analysis reveals that sign language only show little evidence of type 2 grammaticalization and they have the unique possibility of grammaticalising manual and non-manual gestures.