Study on the spatial and temporal distribution of Shell Midden sites in China and their relationship with climate and environment

Abstract

Shell midden sites, archaeological deposits dominated by mollusk remains, serve as critical archives for reconstructing aquatic resource exploitation and human-environment dynamics. Since their 19th-century discovery in Southeast Asia, interdisciplinary approaches (typological, zooarchaeological, and environmental analyses) have established their significance in deciphering prehistoric subsistence patterns and past environmental changes. Shell midden sites are mainly distributed in coastal and riverine-lacustrine areas, with shellfish species categorized as marine or freshwater. The chronological framework of shell midden sites is as follows: during the Late Paleolithic period (approximately 25,000–10,000 yr BP), shell midden sites appeared in inland areas; in the Early to Middle Neolithic period (approximately 9000–5000 yr BP), following the end of the Last Glacial Maximum (LGM, approximately 26,500–19,000 yr BP), marine shell midden sites proliferated in coastal areas. The peak of shell midden sites occurred during the Holocene Climatic Optimum (approximately 8000–5000 yr BP), with climate change, the development of agriculture, and other factors, shell midden sites gradually declined, continuing into the Late Bronze Age (approximately 5000–3000 yr BP). Although previous studies have revealed that climate change, sea-level fluctuations, and shifts in human subsistence strategies contributed to these changes, a comprehensive understanding of when and why shellfish began and ceased to be a primary food source is still lacking. This study analyzes the spatio-temporal distribution of shell midden sites over China and explores how climate and sea-level changes influenced the initiation and cessation of shellfish consumption as a main food source. The findings indicate that climate and sea-level fluctuations significantly affected the distribution of shellfish resources, thus influencing ancient human subsistence strategies and driving the transition to agricultural and pastoral economies. Changes in subsistence strategies accelerated the decline of shell midden sites.