Endangered Tanka Language of the Maritime Communities Across Southeast China: Convergence and Loss

Amidst global concerns for linguistic diversity, this systematic review synthesizes six decades (1965–2025) of research on Tanka, a critically endangered language spoken by the boat people along Southeast China. Analyzing 42 studies identified through the PRISMA framework, the review reveals significant sociolinguistic and epistemological imbalances. Research output disproportionately focuses on phonetics and phonology (50%), while neglecting grammar, lexicon, and sociolinguistic vitality. Linguistically, Tanka demonstrates substantial contact-induced convergence with Cantonese or Pinghua within multilingual ecologies; nevertheless, it retains distinctive phonological shifts, a unique maritime lexicon, and grammatical innovations, reflecting both regional alignment and endogenous community practices. Its heterogeneous genetic affiliation highlights local sociohistorical contact dynamics. Rapid intergenerational language shift is documented across communities, driven by intersecting pressures, including state-led urbanization, Mandarin-centric education policies, demographic shifts, occupational change, and enduring social stigmatization. Therefore, community attitudes often prioritize socio-economic mobility through dominant languages over heritage maintenance. Persistent gaps include limited syntactic and discourse analysis, minimal use of quantitative and computational methods (e.g., AI-assisted documentation), insufficient geographic coverage, and a lack of longitudinal shift studies. The field thus urgently requires enhanced international engagement via English publications and a decisive shift towards collaborative, community-centered revitalization frameworks that address power asymmetries and harness cultural resilience.