The emergence of phonetic naturalness
This dissertation addresses whether synchronic phonology encodes phonetic naturalness. I argue that while phonological grammars allow phonetically unnatural patterns as a result of coincidental historical changes, they are nevertheless biased toward phonetic naturalness. The key observation revealed by experimentation is that phonetic naturalness emerges when speakers create novel phonological patterns. I refer to the observation as "the emergence of phonetic naturalness". To explain the emergence of phonetic naturalness, I propose within Optimality Theory (Prince and Smolensky 2004) that the universal set of constraints is phonetically natural, and constraint rankings are also phonetically natural by default. To accommodate unnaturalness, individual languages can create unnatural constraints and reverse default constraint rankings.
Chapter 1 lays out the issues and Chapter 2 develops a grammatical model. Chapter 3 discusses devoicing of voiced geminates in Japanese loanword phonology. Only voiced geminates, but not voiced singletons, can devoice to dissimilate from another voiced obstruent. I argue that the difference in neutralizability is grounded in a perceptibility scale related to the voicing contrast in singletons and geminates, but that the cause of devoicing, OCP(voice), is phonetically unnatural.
Chapter 4 discusses a novel pattern of Japanese mimetic gemination. When speakers create emphatic forms, they prefer geminate stops the most, geminate fricatives next, and geminate nasals least. The preference hierarchy harmonically aligns with the perceptibility scale for singleton-geminate contrasts for different manners of consonants.
Chapter 5 examines the distribution of vowels that are correspond with Ø in novel Japanese rap rhyming. The likelihood of vowels being treated as Ø directly correlates with their perceptual similarity to Ø.
Chapter 6 shows that in rap rhyming the more perceptually similar two consonants are, the more likely they are to rhyme. The patterns studied in Chapter 5 and 6 show that phonetically natural patterns emergence in novel verbal art.
The case studies suggest that when speakers create novel phonological patterns, they deploy phonetic knowledge, and hence phonetically natural patterns assert themselves.