Laryngeal contrasts and VOT in Hadza stops, affricates, and clicks.

Laryngeal contrasts in consonants (e.g., voicing, aspiration, etc.) are found in nearly all languages. This talk presents acoustic data on laryngeal contrasts in Hadza, a language isolate spoken by ~1,200 people (Brian Wood, pc.). Hadza has a rich consonantal system with contrasts in laryngeal setting and airstream mechanism (e.g., pulmonic, glottalic, and lingual occlusives). Some previous descriptions of Hadza suggested a three-way contrast in coronal stops (e.g., /t tʰ d/), and a four-way contrast in non-coronal stops (e.g., /k kʰ kʼ ɡ/ and affricates (e.g., t͡s t͡sʰ t͡sʼ d͡z), and also a three-way contrast in clicks (e.g., /! !ʰ ǃʔ/) (Tucker et al. 1977; de Voogt 1992). However, these studies did not offer corroborating phonetic evidence. Voice Onset Time (VOT)—the time difference between the release of a stop closure and onset of vocal fold vibration—has proven to be a useful (albeit imperfect) phonetic exponent in the realization of laryngeal contrasts cross-linguistically (Lisker & Abramson 1964). Sands et al. (1996) documented the expected distinction in VOT between voiceless unaspirated and aspirated stops in Hadza, but they did not find significant VOT differences for clicks or affricates. Using wordlist data collected in 2022, this talk presents an analysis of VOT in Hadza stops, affricates, and clicks to examine the temporal properties of laryngeal contrasts. In particular, we examine the differences in VOT between unaspirated, aspirated, and ejective stops and affricates and the differences between unaspirated, aspirated, and glottalized clicks. These results resolve discrepancies between past research and confirm an aspiration contrast in affricates and clicks previously unsubstantiated in the literature. Note: This talk has not gone through a process of peer review, and findings should therefore be treated as preliminary and subject to change. Acknowledgement and citation: Coburn, Jeremy. 2023. Laryngeal contrasts and VOT in Hadza stops, affricates, and clicks. Talk given at the Rift Valley Network Webinar Series. 20/09/2023.