Fine details of a larger picture: Proto-Sakishima *au and *ao diphthongs

Abstract

Abstract Using comparative evidence from the three Sakishima (South Ryukyuan) languages, Miyakoan, Yaeyaman and Dunan, this paper postulates a reconstruction of two Proto-Sakishima *a-initial diphthongs, *ao and *au, and argues that this distinction was carried over to Proto-Miyakoan and Proto-Yaeyaman. The number of vocabulary items traceable to Proto-Sakishima *au is scarce and almost exclusively involves morphologically complex forms, mostly verbs, making the *ao and *au distinction one easy to omit or disregard as random sound change irregularities. Furthermore, most of the modern Sakishima regiolects have lost the distinction between *ao and *au, Tarama-Miyakoan being the only one that consistently maintains the original distinction in all relevant areas of vocabulary and not just verbs, reflecting *ao as /au/ or /oː/ and *au as /uː/. Positing Proto-Sakishima *ao and *au in accordance with the Tarama reflexes begets new insights concerning the *o > *u raising in Sakishima as well as in Ryukyuan in general, thus confirming the slow gradualness of the process and hinting at the chronology of the changes related to this raising. It also reveals a number of specifics concerning the diachrony of Sakishima verb systems, especially the development of conclusive verb forms, thus explaining the apparent discrepancy in *au and *ao reflexes in the regiolects of Miyako and Yaeyama.