Temporal changes in diet and mortuary practices among the Jomon people based on human skeletal remains excavated from the Kawaji shell mound in Aichi Prefecture, Japan

People of the Jomon period in Japan led a hunter-gatherer lifestyle and actively engaged in fishing in coastal areas. On the Atsumi Peninsula, which is located in the southern part of Aichi Prefecture, a number of shell mounds from the Jomon period have been located. More than 30 human skeletal remains have been excavated from the Kawaji shell mound, located at the tip of the Atsumi Peninsula. The Kawaji shell mound was formed from the Middle to Final Jomon period and is thought to be mainly from the Late Jomon period. This study aimed to investigate temporal changes in diet and their relationships with subsistence activities and mortuary practices, which include types of ritual tooth ablation and the location pattern of burials within the site, during the Jomon period. The study material consisted of 20 human skeletal samples from the Kawaji shell mound. Diet was inferred using carbon and nitrogen isotope analysis of bone collagen, and age by radiocarbon dating. Age showed values from the late Middle to the Final Jomon and the Initial to Middle Yayoi periods. Dietary dependence on marine resources increased during the Late Jomon period, and then decreased in the Initial to Middle Yayoi periods. Transition patterns in ritual tooth ablation were also found. Burial subgroups within the shell mound were recognized in each phase. The findings from this case study help shed light on the temporal changes that occurred in the subsistence activities and mortuary practices of the Jomon people.