The proper treatment of NON-DERIVED ENVIRONMENT BLOCKING
(NDEB), also known as the Derived Environment Constraint, has long
been the subject of debate by phonologists. Past approaches include the
Strict Cycle Condition (Mascaró 1976), the Elsewhere Condition
(Kiparsky 1982) and underspecification (Kiparsky 1993). However, since
the introduction of Optimality Theory (McCarthy & Prince 1993, 1994,
Prince & Smolensky 1993), phonologists have tried to model NDEB in
terms of parameterised constraints (e.g. Burzio 1997) or constraint conjunction (e.g. Łubowicz 1998).
In this paper I present a case of NDEB found in the stress patterns of
Tohono O'odham words. Secondary stress is assigned to all odd-numbered
syllables in derived words, but is blocked on word-final odd-
numbered syllables in underived words. I claim that all the presented facts
about Tohono O'odham stress can be accounted for in terms of co-
phonologies (cf. Orgun 1996, Inkelas et al. 1997, Inkelas 1998). By
showing the intricate interaction between, on the one hand, stress
assignment to latent vowels and, on the other, their behaviour with respect
to perfective truncation, I argue that Tohono O'odham stress can be
viewed as being assigned ‘cyclically’ and also as exhibiting the effect of
bracket erasure. These facts, as I will show, are captured naturally by the
co-phonology model. This co-phonology analysis is contrasted with the mono-stratal,
non-constituency-based optimality-theoretic account
argued for in Fitzgerald (1996, 1997). It is demonstrated that the co-
phonology analysis yields a simpler and more explanatory account of the
Tohono O'odham facts than Fitzgerald's account.
I begin this paper with an illustration of the stress patterns of both
underived and derived forms in §2. I will then provide a co-phonology
account for NDEB in §3. An alternative analysis is considered in §3.5. In
§4 I illustrate the interaction between stress, latent vowels and perfective
truncation, and finally the formal analysis is presented in §5.