Comparative Stature Estimation and Skeletal Robusticity in the Indus Valley Civilization Populations: Long Bone Evidence from Three Sites

Abstract This study estimates living stature, quantifies skeletal robusticity and cross-sectional bone shape, and compares three Indus Valley Civilization skeletal assemblages from Rupar, Kalibangan, and Lothal, India. Forty-six adult individuals were analysed using fragment lengths from six long bones (humerus, radius, ulna, femur, tibia, and fibula), with stature reconstructed through a validated two-step regression approach that is appropriate for fragmentary remains and consistent with population-sensitive stature estimation practice. Robusticity Index (RI) and Circularity Index (CI) were calculated to assess diaphyseal form and biomechanical patterning, which are standard approaches for interpreting skeletal loading and activity-related variation. Inter-site comparisons were performed using Kruskal-Wallis and Mann-Whitney U tests with Bonferroni correction, a suitable strategy for small archaeological samples and non-normal distributions. The pooled weighted mean stature was 189.3 ± 20.5 cm, and site means followed a geographical gradient of Rupar > Kalibangan > Lothal, although the difference was not statistically significant (p = 0.21). Femoral RI also showed a non-significant inter-site trend (p = 0.093), with higher values at Lothal suggesting possible differences in lower-limb mechanical loading, but this remains an inference rather than a confirmed site effect. Platymeria and platycnemia were observed in subsets of the sample, but these traits should be interpreted cautiously as possible indicators of repetitive loading or postural behaviour rather than as direct proof of specific activities such as squatting or load-carrying. The results add to the limited bioarchaeological literature on Indus Valley Civilization skeletal populations and support a cautious, population-aware interpretation of stature and robusticity variation.