Investigations into proto-Japonic and proto-Austronesian etyma reveal a highly systematic set of phonetic and semantic correspondances. Several words are manually compared across the Japonic and Austronesian languages from the Oxford-NINJAL Old Japanese Corpus, Eastern Old Japanese Dictionary, Online Dictionary of Japonic Languages, Nikolay Nevskiy’s Miyakoan dictionary and the Austronesian Comparative Dictionary, including data from Baxter-Sagart Old Chinese Reconstructions. Both languages heavily adhere to: bisyllabic phonotactics with medial nasal-obstruent clusters; regular approximations of non-Japonic phonemes into existing proto-Japonic phonemes of similar features; numerous lexical items relating to food, family, and borrowing-resistant vocabulary; sets of reduplicated root to stem correspondances; as well as grammatical parallels. From this data, previous scholarship, historical, and genetic data, it can be gleaned that Austronesian peoples must have arrived around the Late Jōmon Period in Kyūsyū and/or the southern Korean peninsula. These linguistic discoveries may elucidate this otherwise mysterious period of migration in Japonic prehistory.
Bianca Corona Aguilar (Sat,) studied this question.
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