2007/01/01 by Kuniaki Haneji, Tsunehiko Hanihara, Hajime Sunakawa +2 · 3 citations
Arts and Humanities · Biochemistry, Genetics and Molecular Biology · Environmental Science · #Forensic Anthropology and Bioarchaeology Studies #Forensic and Genetic Research #Wildlife Ecology and Conservation #Pacific islanders #Geography #Divergence (linguistics) #Tooth crown #Demography #Variation (astronomy) #Biology #Population
paper · pdf · doi:10.1537/ase.060206
openalex publication_date 2007/01/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
Twenty-four non-metric tooth crown traits of Miyako and Ishigaki Islanders, from the southernmost Ryukyu Islands, were investigated and compared with those of neighboring populations. The frequency of double-shoveling in Sakishima samples, and especially, Ishigaki Island, is lower than that found among Atayal people (Taiwan) and main-island Japanese. The frequencies of protostylid and cusp 6 in Miyako and Ishigaki Islanders are comparable to those in Hokkaido Ainu and lower than in main-island Japanese and Atayal. Miyako and Ishigaki Islanders, as well as other Ryukyuans, are basically more similar to main-island Japanese than to Ainu, while being situated between main-island Japanese and Ainu in terms of both mean measure of divergence (MMD) and R-matrix methods. However, Ishigaki and Miyako Islanders are relatively close to Hokkaido Ainu among Ryukyu people and main-island Japanese, as suggested in some previous preliminary studies. The estimated Fst (the ratio of among-group variation to total variation), using an average heritability rate = 0.55 for the non-metric tooth crown traits used in this study, displayed low levels of inter-regional variation, as already indicated in analyses of genetic, cranial and dental metric data. Meanwhile, the relatively large diversity of Ryukyu Islanders based on Fst suggested long-term isolation or poor intra-island contact among the Ryukyu Islands. The lower observed variation compared with the expected variation in most Ryukyu samples may reflect a greater degree of genetic drift in the Ryukyu Island chain.