Drawing on the architectural underpinnings of Lexical Phonology (Kiparsky 1982; Mohanan 1986), a body of research on the diachrony of phonological patterns has proposed that such patterns are unidirectional: they emerge from phonetic precursors, undergo phonologization, and transition from phrasal to lexical and stem-level domains. The proposed life cycle of a diachronic process terminates with formerly productive patterns becoming morphological or lexicalized (Bermu?dez-Otero 1999, 2007; Ramsammy 2015).
This talk considers various aspects of the emergence and decay of vowel harmony in Turkic and Uralic. While some cases of decay follow the pathways predicted by previous research, in particular, by the Life Cycle Model, and result in morphologization and lexicalization, others exhibit domain contraction to domains smaller than the word that cannot be defined with reference to phonological or morphological constituents, a development not predicted by the model. An analysis that accounts for a broader range of possible evolutionary paths of vowel harmony patterns will be proposed.