Open Access

Nicholas Evans

• Most systematic discussion of dyad morphemes has focussed on Australian languages, owing to a combination of their relative prevalence there, and the development of a descriptive tradition that investigates them in some depth. In the course of researching this paper, however, I became aware of functionally and semantically similar morphemes in many other parts of the world, almost invariably described in isolation from any typological reference point. I have incorporated such data as far as I am aware of it, in the hope that a systematic study will encourage other investigators to identify, and investigate in detail, similar constructions in a range of languages. The current state of our research, however, as well as some interesting geographical skewings that I discuss below, such that outside Australia dyad constructions almost exclusively employ reciprocal morphology, means that most of this paper will focus on Australian languages.