Modeling the gradient evolution and decay of harmony systems

The diachronic trajectories of vowel harmony systems have been understudied but offer significant insight into both the possible domains of vowel harmony as well as the interaction between phonetic coarticulation and phonological harmony. This paper proposes a novel analysis of decaying labial harmony in Kazakh, unifying phonetics and phonology in one formalism (Flemming 2001) that incorporates both abstract morpho-phonological and temporal phonetic factors to drive the gradient harmony pattern in contemporary Kazakh. These factors are defined and implemented in a regression-like model that accurately predicts the degree of coarticulation on non-initial vowels. The structure of the model is then discussed in diachronic terms, outlining the development and decline of harmony, as predicted by the model. Significantly, these predictions are supported by typologically attested domains of harmony among the world's languages. The model developed herein is thus able to accurately predict the fine-grained degree of coarticulation in Kazakh, as well as suggest a plausible pathway for the evolution and decay of harmony patterns more broadly.The diachronic trajectories of vowel harmony systems have been understudied, but offer significant insight into both the possible domains of vowel harmony as well as the interaction between phonetic coarticulation and phonological harmony. This paper proposes a novel analysis of decaying labial harmony in Kazakh, unifying phonetics and phonology in one formalism (Flemming 2001) that incorporates both abstract morpho-phonological and temporal phonetic factors to drive the gradient harmony pattern in contemporary Kazakh. These factors are defined and implemented in a regression-like model that accurately predicts the degree of coarticulation on non-initial vowels. The structure of the model is then discussed in diachronic terms, outlining the development and decline of harmony, as predicted by the model. Significantly, these predictions are supported by typologically attested domains of harmony among the world's languages. The model developed herein is thus able to accurately predict the fine-grained degree of coarticulation in Kazakh, as well as suggest a plausible pathway for the evolution and decay of harmony patterns more broadly