ABSTRACT
This chapter compares the duration of individual vowels to that of lexical diphthongs, diphthongs resulting from hiatus resolution, and hiatus. Vowel duration measurements are performed based on auditory identification and the visual inspection of formants, using the PRAAT software. The chapter proposes that the main difference between vowels and glides is the position each one occupies in the syllable. By default, non-nuclear vowels are shorter than nuclear vowels. This is a subphonemic difference that licenses the correct syllabification of segments in different registers and across morpheme boundaries. A distinction based on positional restrictions allows us to eliminate the need for mechanisms such as partial prespecification of syllable structure or the need for features such as [syllabic] to distinguish vowels from glides. The chapter describes hiatus resolution and preservation in vernacular varieties of Puerto Rican Spanish, provides evidence that this dialect is not exceptional among other Spanish varieties, and matches similar phenomena in other languages.
