Same, similar, or different: Lexical overlap across Australian Indigenous signed languages

Abstract

To date, studies that investigate lexical overlap in signed languages have mainly considered the relationships between deaf community signed languages. The alternate sign languages of Indigenous Australia provide an opportunity to take another perspective – they are perhaps amongst the oldest known sign languages in the world, their main users are hearing, and senior people are the acknowledged experts, at least in some domains of sign knowledge and use. We developed a comparative list of signs as one tool in an investigation of dimensions of similarity and difference in nine language communities from Central and Northern Australia. We coded the data for the articulatory parameters of handshape, place of articulation, and movement, and developed a comparison matrix that captured similarity by using alphanumerical labels for unique sign forms. In doing so, we accommodated the existence of both inter- and intra-signer variation within single communities, a factor that has been overlooked in some previous studies. Our results support earlier observations that correlate sign diversity with geographical distance. We identify two distinct clusters of communities within which are higher percentages of lexical overlap. The first of these includes the Warlpiri, Anmatyerr, Alyawarr, and Arrernte language groups, while the second cluster includes Gurindji, Mudburra, and Kukatja. We note a general stability in lexical overlap (i.e., shared lexicon) in comparison to earlier records, but also an increase in similarity, suggesting some convergence might be taking place. Finally, we point to the need to unpack the complex sociocultural and linguistic factors that interact to drive similarity and difference in these signing practices. The list of commonly known signs, and the methods we have developed, is a useful resource that can inform future comparative studies.