Relating application frequency to morphological structure: the case of Tommo So vowel harmony

• Published in: Phonology Vol. 33; no. 1; pp. 125 - 167
• Main Authors: McPherson, Laura, Hayes, Bruce
• Format: Journal Article
• Language: English
• Published: Cambridge, UK Cambridge University Press 01-05-2016
• Subjects: Grammar; Language; Morphemes; Morphological analysis; Morphology; Morphophonemics; Niger-Congo languages; Phonemes; Phonetics; Phonology; Scalarity (Semantics); Speech; Suffixes; Vowel harmony; Vowels; Los Angeles California; California; Mali; United States > US
• ISSN: 0952-6757; 1469-8188
• DOI: 10.1017/S0952675716000051

We describe three vowel-harmony processes in Tommo So and their interaction with
morphological structure. The verbal suffixes of Tommo So occur in a strict linear
order, establishing a Kiparskian hierarchy of distance from the root. This distance
is respected by all three harmony processes; they ‘peter out’, applying with lower
frequency as distance from the root increases. The function relating application rate
to distance is well fitted by families of sigmoid curves, declining in frequency from
one to zero. We show that, assuming appropriate constraints, such functions are a
direct consequence of Harmonic Grammar. The crucially conflicting constraints are
Ident (violated just once by harmonised candidates) and a scalar version
of Agree (violated one to seven times, based on closeness of the target to
the root). We show that our model achieves a close fit to the data, while a variety
of alternative models fail to do so.