This paper is the first systematic assessment of the phonetics and phonology of Ayoreo, a Zamucoan language spoken in the Chaco region of southeastern Bolivia and northern Paraguay. Ayoreo has a fairly simple phonotactic structure and a medium-sized phonematic inventory, consisting of 5 vowels and 15 to 17 phonemes, depending on the variety. The consonant system presents some typologically relevant issues: the uncertain word-stress location; the vanishing rhotic and its relation to vowel lengthening; devoiced nasals and the effect of nasal harmony; and the elusive role of the word-final glottal stop. Despite the small number of speakers (less than 5,000), Ayoreo presents remarkable dialectal variations, and even intraindividual oscillations, which – lacking a recognized standard – constitute a challenge for the phonologist.
Bertinetto et al. (Wed,) studied this question.