Geographical Variation of Dental Characteristics in the Japanese of the Protohistoric Kofun Period

Metrical and nonmetrical crown characteristics in the permanent dentition were investigated for seven protohistoric Kofun population samples from western and eastern Japan. The difference between the western and eastern Kofun series was significant in only one measurement in males, whereas in five measurements in females. The metrical analysis of female dentition indicated that the Kofun series of eastern Japan had a slight resemblance to the prehistoric Jomon series which were characterized by smaller overall crown size. However the overall crown sizes of the other Kofun series were larger than those of the Jomon and recent series of Japan. From these results, it was inferred that the Kofun series were closely tied to the Aeneolithic Yayoi series of immigrant type characterized by larger overall crown size, and that the genetic influence of the immigrants in eastern Japan was greater on males than on females during the Kofun period. On the other hand, the nonmetrical data showed close affinities between the recent Japanese series and both the Kofun series of western and eastern Japan, with a large gap between the Kofun and Jomon series. These results suggested that the distribution pattern of nonmetrical crown characteristics of the recent Japanese series had been constructed, at the latest, by the end of the Kofun period.