The contrastive hierarchy in phonology 2009 Dresher.pdf - CUNY ...

Constraint (8.1a) provokes labial harmony triggered by both high and low round
vowels, as occurs (potentially) in Turkic languages; (8.1b) is meant to account for
the Manchu-Tungus-Mongolian type of labial harmony, which is triggered only
by low vowels.
If grammars are permitted to freely rank these constraints, we would have
no explanation for the correlation between inventories and type of labial
harmony. It remains to be explained why Manchu-Tungus-Mongolian languages
typically use EXTEND[RD]IF[–HI], whereas Turkic languages use EXTEND[RD]. To
account for this correlation, Kaun proposes that EXTEND[RD]IF[–HI] is dominant
only if there is greater perceptual crowding in the non-high vowels than in the high
vowels. To implement this notion in her formal theory, she adopts the
convention that EXTEND constraints may operate only on contrastive feature
values.
Kaun 1995 proposes no theory for identifying which values are
contrastive. However, since her constraints do not refer directly to perceptual
crowding but only to contrast, it follows that in her theory a segment has a
contrastive feature if and only if it is crowded.
Deriving contrast from crowding is problematic when we consider
languages like Yowlumne Yokuts. As we saw in §5.3, Yowlumne Yokuts has
height-bounded labial harmony triggered by both high and non-high vowels.
The Yowlumne high vowel space is not crowded, however; on the contrary, it
has optimal separation (8.2).
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