Innovations, distribution gaps and mirror images: The reflexes of Proto-Ryukyuan close vowels in a post-nasal position

Abstract

Abstract The present paper attempts to systematize and explain the changes in Proto-Ryukyuan (PR) vowels in a post-nasal position as observed in the lexicon of five daughter languages: Ie-Kunigamian/Okinawan, Shuri-Okinawan, Hirara-Miyakoan, Shika-Yaeyaman and Yonaguni/Dunan. The changes in question are related to the mid-vowel raising, which supposedly occurred only after the split of PR, but currently bears the markings of an unconditioned change in virtually in all daughter languages. Starting with an assumption that in some environments, the post-nasal raising of the mid-vowels led to the merger of original mid- and close vowels, while in different environments changes to the original close vowels keeps the reflexes of mid- and close vowels apart, the paper analyzes and compares Ryukyuan vocabulary containing the pertinent sound sequences of *mi, *mu, *ni and *nu, contrasting it with the reflexes of *me, *mo, *ne and *no. By scrutinizing in detail as many different environments of the sound sequences in question as possible, the paper aims to discover some patterns in the behavior of these sequences, examining both shared innovations and shared retentions among the daughter languages, observing the differences in the PR distribution of post-nasal mid-and close vowels, and entertaining the implications these findings hold for the general knowledge of PR.