Identical Tones and the OCP in Èwùlù: An Optimality Account


  • Don C. Utulu Faculty of Arts, Delta State University



Èwùlù, OCP, Optimality Theory, tonal patterns, tones


The Obligatory Contour Principle (OCP) potentially acts as a constraint on adjacent identical tones. This is why, in tone languages, underlying /HHL/ and /LLH/ may surface as [HL] and [LH] respectively. Èwùlù (Igboid: West-Benue Congo, Nigeria), a relatively unknown small dialect, exhibits such OCP-motivated adjustments on adjacent identical tone structures. Adopting the Optimality Theory, this study accounts for the tonal modifications in order to complement the earlier findings in the literature that advance our understanding of how the OCP shops for adjacent identical tones in representations but may fail to do so due to attested structural exceptions in its tonology. Therefore, the study examines tonal patterns such as, juncture tone deletion, consecutive high and low tones, tonal affix, downstep and final high tone displacement. The findings showed that the OCP can be dominated by some higher-ranked constraints in the Èwùlù tonal grammar, like is the case in some languages,. This study draws some theoretical implication. The Èwùlù tonal system provides further evidence that suggests the OCP is not universal; it is violable just like other constraints active in Universal Grammar.

Author Biography

Don C. Utulu, Faculty of Arts, Delta State University

Department of Languages and Linguistics


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