Dental metric variability associated with human migration from skeletal remains of two Jomon sites (Yoshigo and Inariyama) in the Atsumi Peninsula area

Abstract

This study investigated interpopulation genetic relationships in the Jomon Atsumi Peninsula area, comparing the pattern of human migration revealed by strontium isotope ratio with dental metric variation of Yoshigo and Inariyama skeletal remains. Morphological differences were evaluated between the local and immigrant groups to determine whether or not local populations had become completely homogenized by human migration. We have constructed 4 × 4 contingency tables consisting of four clusters derived from K-means clustering of dental measurements and four groups (immigrants and locals of the two sites), and evaluated their correlations by Fisher's exact test. The results revealed that human migration pattern was significantly correlated with dental metric variation, suggesting that there was regional heterogeneity among Jomon populations in the Atsumi Peninsula area. Although the distinction between immigrants and locals of Yoshigo and Inariyama populations based on strontium isotope analysis was not completely in accord with dental metric variability, most of the identified immigrants exhibited dental profiles that were beyond each local profile as determined using principal component analysis. Furthermore, the dental metric variances of the immigrants were significantly larger than those of the locals, suggesting multiple origins. The microdifferentiation among populations in the Atsumi Peninsula area may suggest nonrandom kin-structured migration and/or population aggregation from surrounding areas.

Peopling the Americas: Not “Out of Japan”

“…Additionally, the small population size of hunter-gatherer populations like Jomon, coupled with isolation and population differentiation across the archipelago, is consistent with stochastic effects on the genome. Such stochastic effects (genetic drift) are equally powerful modifiers of morphometric phenotypes (Fukase et al 2012;Morita et al 2012;Schroeder and von Cramon-Taubadel 2020;von Cramon-Taubadel 2019). Such patterns of diversity and differentiation among geographically dispersed Jomon might well result in the expanded variation observed in Jomon dental morphology and the apparent affinity of these morphological phenotypes with a variety of early ancestral and subsequent descendant groups.…”