Reconstructing Cranial Modification Practices: Methods, Motivations, and Evolution of Occipital Modification in Prehistoric China

Occipital modification, the predominant form of cranial artificial modification in Prehistoric China, is characterized by its extensive and dense distribution, a rarity globally. This study aims to reconstruct the methods, processes, and motivations underlying occipital modification, investigating its inception, evolution, and eventual cessation in Prehistoric China. Morphological observations were conducted on over 800 individuals from representative sites like Baligang and Chuwan of the Yangshao culture, with 265 well-preserved skulls subjected to three-dimensional scanning, modeling, and measurement, segmented into BLG-E, BLG-M, and CW groups for detailed analysis. Observations and measurements revealed significant differences in occipital modification among the groups: the BLG-E group displayed a high modification rate, featuring severe modification with a near-perpendicular tilt angle and random lateral asymmetry; the BLG-M group exhibited reduced modification rate and severity, with lateral asymmetry akin to BLG-E but more variable tilt angles; and the CW group showed moderate occipital modification with variable tilt angles, though with greater central symmetry. Two distinct practices were identified: “primary utilitarian modification,” likely an expedient measure for infant care during early agricultural development, and “standardized symmetrical modification,” reflecting aesthetic preferences during a more mature agricultural stage. Following the transition from utilitarian to aesthetic purposes, the occipital modification disappeared in the Final Neolithic period, during the Longshan culture stage, possibly because of the emergence of new, complex hairstyle trends.