Associate Professor Carmel O'Shannessy presented a paper called 'Code-switching as a way of talking – from language shift to language maintenance' at the Australian National University, Canberra, Australia, on March 5.

Abstract
Code-switching was a major factor in the emergence of the mixed language, Light Warlpiri, and therefore in a partial shift away from speaking Warlpiri as the speakers' primary language. Now, Light Warlpiri speakers make use of both Light Warlpiri and Warlpiri verbal resources to organise discourse, with a by-product of promoting maintenance of Warlpiri. This paper responds to Simpson's (2015) call for "much more work … to discern the variation of ways of talking which occurs during times of rapid [language] change", by documenting code-switching by multilingual speakers in a community undergoing rapid change. In the 1970-80s adult speakers of Warlpiri in one community code-switched to very young children in a specific pattern that was then conventionalized by the children as a single code. Defining features of Light Warlpiri are re-analysed verbal structure, derived from English and Kriol, with some innovations, combined with the Warlpiri nominal case-marking system (O'Shannessy, 2013). Light Warlpiri and Warlpiri are differentiated by verbal lexicon and verbal structure. Light Warlpiri speakers code-switch fluidly between between Light Warlpiri and Warlpiri, and they consider the interaction of multiple codes part of their local speech style. The data are of two types. One set is recordings of elicitation sessions where Light Warlpiri speakers spontaneously created scenarios, or recounted events, to illustrate their use of particular verbs. In the scenarios and recounts, when providing examples of actual or imagined speech, the speakers code-switch between Light Warlpiri and Warlpiri verbal lexicon and structures. The other set, more naturalistic, is recorded interactions of Light Warlpiri speakers telling a story from picture stimulus (Carroll, Evans, Hoenigman, & San Roque, 2009). In this paper I will present the code-switching data, and analyse the motivations for the code-switches using Gumperz' (1982) and Poplack's (1980) discourse organising factors. I argue that code-switching between Light Warlpiri and Warlpiri for discourse purposes keeps some elements of Warlpiri verbal lexicon and structure accessible to Light Warlpiri speakers, even when not speaking Warlpiri for sustained periods of time. The same kinds of discourse patterns are seen in the more, and less, naturalistic types of data, suggesting high data validity. References: Carroll, Alice, Evans, Nicholas, Hoenigman, Darja, & San Roque, Lila. (2009). The family problems picture task. Designed for use by the Social Cognition and Language Project. Canberra: The Australian National University Griffith University of Melbourne Max Planck Institute for Psycholinguistics. Gumperz, John J. (1982). Discourse strategies. Cambridge & New York: Cambridge University Press. O'Shannessy, Carmel. (2013). The role of multiple sources in the formation of an innovative auxiliary category in Light Warlpiri, a new Australian mixed language. Language, 89(2), 328-354. Poplack, Shana. (1980). Sometimes I'll start a sentence in Spanish y termino en Espanol: toward a typology of code-switching. Linguistics, 18, 581-618. Simpson, Jane. (2015). Language attrition and language change. In Claire Bowern & Bethwyn Evans (Eds.), The Routledge Handbook of Historical Linguistics (pp. 537-554). London: Routledge.