Broad-spectrum foodways in southern coastal Korea in the Holocene: Isotopic and archaeobotanical signatures in Neolithic shell middens

Expanding diet breadth to previously unexplored resources was a key strategy in Neolithic adaptation through the Holocene. Most prominently, marine resources became substantial supplements in coastal and island regions worldwide. The Neolithic culture in Korea, known as the Chulmun, has been viewed as heavily based on a marine diet, as a large number of sites are shell middens with well-preserved marine resources. Terrestrial animal taxa are also documented in shell middens, but plant resources have been rarely reported because of the absence of archaeobotanical research. To help fill in this gap, we compared archaeobotanical and organic residue isotope data from four Neolithic shell middens, including Beombang, Bibongri, Sejukri, and Tongsamdong (7500 to 4000 cal BP). Results indicate that ca. Coastal inhabitants procured a broad-spectrum of resources from both marine and terrestrial taxa, while maintaining some difference in resource procurement across settlements from the Early Neolithic period. Particularly, the longer the occupation was, the wider the diet breadth became, including various plant resources and terrestrial animals. Our research demonstrates the utility of integrating archaeobotanical, grain impression, and isotopic methods, while building an additional robust case study demonstrating long-term niche construction and diverse resource seeking in coastal regions in the area.