Synchrony and diachrony of the Eastern Andalusian Spanish vowel system

Eastern Andalusian Spanish (EAS) features an expanded vowel system with additional lax or -ATR vowels—[ɛ, ɔ, a̞~æ]—that arise word-finally through the deletion of -s and -r. These vowels have been described as triggering leftward -ATR harmony, producing alternations such as beso [ˈbeso] vs. besos [ˈbɛsɔ]. While mid vowels are well studied, the role of high and low vowels in these processes remain less clear. Previous work highlights some facts that are not easily explained by phonetic factors: that high vowels do not undergo laxing but may be transparent to -ATR harmony, as well as the low vowel laxing word-finally but not undergoing harmony. Tense vowels in EAS have also received limited experimental attention, despite their potential role on the development of laxing. This study investigates word-final laxing, harmonization, and transparency of EAS vowels focusing on the /i e a/ continuum. 29 speakers from Granada were tested in an elicited production task. Results show that /i/ does not undergo laxing in any environment, while /a/ lowers and may front only in word-final position. However, when a word end in -is (realized as a tense [i]), a preceding /e/ surfaces as [ɛ]. In addition, non-mid vowels are found to act ‘transparently’. The study further finds that tense /e/ in EAS is somewhat more peripheral than in Standard Spanish and resists backing in contexts that typically induce centralization, which suggests some role of tensing in the development of laxing. Overall, the distribution of tense and lax vowels in EAS supports a synchronic word-level constraint requiring agreement in mid-vowel laxness/tenseness across the word, with limited participation from /a/. Since the distribution of lax vowels lacks a phonetic basis, these findings point away from an active feature-spreading process and point out at the role of diachrony in shaping present-day harmony patterns. These findings present clear implications for the analysis of other harmony systems in other languages.