Phonetic naturalness in the reanalysis of Samoan thematic consonant alternations

Paradigms with conflicting data patterns can be difficult to learn, resulting in a type of language change called reanalysis. Existing models of morphophonology predict reanalysis to occur in a way that matches frequency distributions within the paradigm. Using evidence from Samoan, this paper argues that in addition, reanalysis may be constrained by phonotactics (global distributional regularities in the lexicon) and phonetic substance. More concretely, I find that reanalysis of Samoan thematic consonants generally matches distributional patterns within the paradigm. However, reanalysis is also modulated by a phonotactic dispreference against sequences of homorganic consonants, analyzed here in Optimality Theoretic terms by OCP-place. These results are supported by an iterated learning model that is based in MaxEnt (Goldwater and Johnson, 2003). In a study where phonetic similarity is measured as the spectral distance between two phones, I find that similarity of consonants is closely correlated with the strength of OCP-place effects in Samoan; this suggests that OCP-place is rooted in phonetic similarity avoidance, and more generally that in reanalysis, speakers preferentially utilize phonetically-motivated phonotactics.