ATR harmony in Turkana

This paper analyzes the [ATR] harmony system of Turkana (Eastern Nilotic). The principal claim made in this paper is that Turkana provides evidence for an underlying ternary contrast in the feature [ATR]. This claim is based on the observation that some suffixes alternate in [ATR] in agreement with a preceding root, while other sufflxes surface as either [+ATR] or [-ATR], regardless of the context in which they occur. The claim that non-alternating suffixes are specified for [ATR] is supported by the fact that they cause regressive assimilation: a [-ATR] root surfaces as [+ATR] if followed by a [+ATR] sufflx; a [+ATR] mid vowel root surfaces as [-ATR] if followed by a [-ATR] suffIX. Turkana thus provides evidence that the feature [ATR] is ternary with the three values [+ATR], [-ATR] and [()ATR].