Reduction of the diphthong system in the Odul language

This study examines the phonetic evolution of the endangered Odul language (Forest Yukaghir) by analyzing the diachronic development of its diphthong system. There is a significant discrepancy between the rich inventory of diphthongs documented in early linguistic records and their uncertain status in the contemporary language, which is now spoken by only a few elderly individuals. Hence, the primary objective is to verify the current existence and phonetic realization of these historical vocalic complexes using modern instrumental methods. The methodology involves an acoustic analysis of field recordings from the last native speakers, employing oscillography, spectrography, and analysis of intensity and fundamental frequency. A key aspect is the application of a novel classification framework focusing on the number of vocalic nuclei and glottalization to distinguish between true diphthongs, monophthongs, and complex vocalic units. The results demonstrate a near-complete systemic reduction. Only one diphthong, [iѢe], retains its historical phonetic structure. The diphthongs [aѢi], [eѢi], [oѢi], [uѢi], [eѢu], [aѢu] and [a], are reinterpreted as vowel-glide sequences, while [uѢo], [uѢө], and [eѢo] have undergone monophthongization. Furthermore, the orthographic representations of [оѢu] and [өѢu] prove to correspond not to diphthongs but to vowel-fricative sequences, classified as fictitious diphthongs. The conclusion is made that the collapse of the diphthong system is an inherent, long-term phonetic process rather than a result of recent external influence. These findings are crucial for an accurate description of Odul phonetics, language documentation, orthography standardization, and potential revitalization efforts, while also contributing to the broader typology of phonetic change in obsolescent languages

Diphthong · Historical linguistics · Typology · Language, Linguistics, Cultural Analysis · Linguistics and Cultural Studies · Phonetics and Phonology Research