Do dental nonmetric traits actually work as proxies for neutral genomic data? Some answers from continental- and global-level analyses

Objectives: Crown and root traits, like those in the Arizona State University Dental Anthropology System (ASUDAS), are seemingly useful as genetic proxies. However, recent studies report mixed results concerning their heritability, and ability to assess variation to the level of genomic data. The aim is to test further if such traits can approximate genetic relatedness, among continental and global samples. Materials and Methods: First, for 12 African populations, Mantel correlations were calculated between mean measure of divergence (MMD) distances from up to 36 ASUDAS traits, and FST distances from >350,000 single nucleotide polymorphisms (SNPs) among matched dental and genetic samples. Second, among 32 global samples, MMD and FST distances were again compared. Correlations were also calculated between them and inter-sample geographic distances to further evaluate correspondence. Results: A close ASUDAS/SNP association, based on MMD and FST correlations, is evident, with rm-values between .72 globally and .84 in Africa. The same is true concerning their association with geographic distances, from .68 for a 36-trait African MMD to .77 for FST globally; one exception is FST and African geographic distances, rm = 0.49. Partial MMD/FST correlations controlling for geographic distances are strong for Africa (.78) and moderate globally (.4). Discussion: Relative to prior studies, MMD/FST correlations imply greater dental and genetic correspondence; for studies allowing direct comparison, the present correlations are markedly stronger. The implication is that ASUDAS traits are reliable proxies for genetic data—a positive conclusion, meaning they can be used with or instead of genomic markers when the latter are unavailable

Taiwan Aboriginals and Peoples of the Pacific-Asia Region: Multivariate Craniometric Comparisons.

RefereedStepwise discriminant function analysis and Mahalanobis’s generalized distance are applied to twenty-nine cranial measurements recorded in 2,531 male crania representing five Taiwan aboriginal cranial series and fifty prehistoric, modern, and near modern human groups. The Taiwan aboriginal cranial series include modern samples of Atayal, Bunun, Pazeh, Babuza, and archaeological human remains from the Shi San Hang site (ca 1800-500 BP). The comparative cranial series represent East Asia, Southeast Asia, Australia, New Guinea, island Melanesia, Polynesia, and Micronesia. The results of two separate analyses, one using five and the other using fifty-five groups, are presented. A relatively close connection between the Babuza, Pazeh, and Shi San Hang aboriginal cranial series is observed while the Atayal and Bunun series remain relatively well differentiated. Connections between Taiwan aboriginal groups and cranial series from Polynesia suggest that Taiwan’s aboriginal inhabitants may have been the ancestral source of these inhabitants of Remote Oceania. Similarly, these results suggest that the ultimate source of Taiwan’s prehistoric and modern aboriginal groups may be among the early inhabitants of eastern (Northeast or Southeast) Asia. The results of the present craniometric analysis are compared with other lines of evidence which have been used to examine the affinities and origins of Taiwan’s aboriginal peoples