Tone, stress, and their interactions in Cushillococha Ticuna

Ticuna (ISO: tca; Peru, Colombia, Brazil) displays a larger tone inventory – five level tones – than any other Indigenous American language outside Oto-Manguean. Based on recent fieldwork, this article argues that, in addition to these tone properties, the Cushillococha variety of Ticuna also displays stress. Stress corresponds to morphological structure, licenses additional tonal and segmental contrasts, conditions many phonological processes, and plays a central role in grammatical tone processes marking clause type. Empirically, these findings expand our understanding of word prosody in tone languages in general and Amazonian languages in particular. Theoretically, they challenge current models of stress-conditioned phonology and grammatical tone.