Variation and reorganisation in a minimal tonal system: evidence from Wuwei Mandarin

Small tonal inventories may exhibit substantial internal structure when they arise through historical category reduction. This study examines how such structure is organised across speakers in Wuwei Mandarin and how present-day tonal variation relates to Middle Chinese provenance. Citation-tone productions from 22 speakers were analysed using speaker-specific Dynamic Time Warping and Partitioning Around Medoids clustering, descriptive profile classification, and Generalised Additive Mixed Models of within-group F0 trajectories. The speaker-specific optimal- k assessment selected two-group solutions for 19 of the 22 speakers and three-group solutions for the remaining three. In a separate correspondence check, the k = 2 candidate partitions yielded distinct Falling- and Non-Falling-majority clusters for 20 speakers. Within Non-Falling, cross-speaker variation could be summarised by Mid-level, Peaking and Rising phonetic profiles, which differed primarily in the time course of their F0 trajectories rather than in overall F0 level. Middle Chinese provenance was strongly associated with the broad Falling–Non-Falling outcome but only weakly associated with profile variation within Non-Falling; píng - and shǎng -derived items showed nearly identical profile distributions. At the speaker level, profile distribution showed a preliminary association with gender in the present sample, but no overall association with age. These findings reveal level-specific historical conditioning in a historically reduced tonal system: historical provenance is strongly reflected in broad tonal outcomes but is only weakly reflected in recurrent within-group phonetic variation.