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Whether gemination or fusion, double teeth are rare worldwide, including Africa based on few published data. New cases from the continent are tallied, and anomalies potentially associated with double teeth are identified. These findings should interest a range of dental researchers.

The presence of double teeth was recorded in 97 modern and premodern North and sub‐Saharan African samples (5631 inds.). They and coexistent anomalies are described relative to published examples. Prevalence was estimated as possible, using a Poisson model for 95% confidence intervals (CI).

Three maxillary double teeth were identified: a primary left lateral incisor in a Nubian child (1938–1756 BC), permanent left central incisor in an adult Egyptian (3650–3500 BC), and permanent right central incisor in a modern (19th century) adult from Guinea. Each co‐occurs, respectively, with a talon cusp, peg lateral incisor and, in the latter individual, second premolar crown variation with rotation, and third molar dens evaginatus. Double tooth prevalence is 0.048% (CI 0.001%–0.270%), with regional variation, in premodern, and 0.000% in modern North Africans. It is 0.000% for premodern and 0.048% for modern sub‐Saharan Africans (0.008%–1.714%).

The double incisors are comparable to other global examples, indicative of common developmental processes during odontogenesis. Prevalence is lower than published modern rates, to suggest some exceptionality in Africans as reported earlier for other dental variants. Finally, though circumstantial, double teeth and accompanying anomalies may share an etiology. Continuing research overall, and in Africa specifically, will promote an improved understanding of double teeth formation and expression.

Although rare, tooth transposition—an exchange in location of two teeth—is a frequent topic of study. Clinical and, to a much lesser extent, dental anthropological research have focused predominantly on prevalence (0.03%‐0.74% in several world populations) and case studies, albeit on a restricted spatiotemporal scale. Many regions have received little attention, including sub‐Saharan Africa, while premodern data are few. Here, the aim is to supplement both fields of dental research by reviewing previous publications, and newly reporting transposition rates, types, and co‐occurring abnormalities in time‐successive samples across the subcontinent.

Dental data in 51 sub‐Saharan samples (>2500 individuals) dating >10 000 BC to 20th century were recorded. Of these, 36 are of modern and 15 premodern age, comprising males and females ≥12‐years of age. Transposition presence, quadrant, and type were tabulated, cases described, and prevalence presented. In the latter case, Poisson 95% confidence intervals were calculated to better discern true population rates at various geographic levels.

Overall, six of 1886 modern individuals (0.32%) and one of premodern age evidence Mx.C.P1, an exchange of the maxillary canine and first premolar. Various associated dental abnormalities are also evident, including retained deciduous teeth, reduced permanent crowns, and agenesis.

This study provides additional insight into the geographic distribution, features, and time depth of transposition, along with hints supporting a genetic etiology and, potentially, some indications of diachronic change from an initial Mx.C.P1 to several types more recently based on premodern evidence. It is of clinical concern today, but is not just a modern anomaly.

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.

First, for 12 African populations, Mantel correlations were calculated between mean measure of divergence (MMD) distances from up to 36 ASUDAS traits, andF_STdistances from >350,000 single nucleotide polymorphisms (SNPs) among matched dental and genetic samples. Second, among 32 global samples, MMD andF_STdistances were again compared. Correlations were also calculated between them and inter‐sample geographic distances to further evaluate correspondence.

A close ASUDAS/SNP association, based on MMD andF_STcorrelations, is evident, withr_m‐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 forF_STglobally; one exception isF_STand African geographic distances,r_m= 0.49. Partial MMD/F_STcorrelations controlling for geographic distances are strong for Africa (.78) and moderate globally (.4).

Relative to prior studies, MMD/F_STcorrelations 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.