Subsistence strategy and tibial shape : identifying variation in activity across the Sudanese landscape

• Main Author: Hackner, Stacy
• Other Authors: Hillson, S. W. ; Antoine, D. ; Rando, C.
• Published: University College London (University of London) 2017
• Subjects: 930
• Online Access: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.746828

The growing human tibia is uniquely responsive to repeated activities, resulting in identifiable morphological patterns that can be applied to ancient populations. Much of the bioarchaeological research in this area focuses on the transition to agriculture, noting a decline in bone strength and robusticity with increasing levels of sedentism. However, not all human groups adopted agriculture simultaneously or uniformly, and there continues to be variation in subsistence strategy based on climate, resource availability, and cultural practice. In Sudan, groups have continued to practice nomadic pastoralism alongside agriculture, although sedentary agricultural societies tend to be the focus of most archaeological research in the region. This work examines the difference in tibial morphology between groups utilising different subsistence practices within the same geographic region and archaeological period to explore activity-based changes to the tibia, using both cross-sectional geometry and geometric morphometrics to quantify the difference between tibial cross-sectional shapes at midshaft. The results suggest that while clear differences exist in midshaft tibial shape between the Sudanese groups practicing differing subsistence strategies, there is no one shape that is indicative of nomadism or sedentism; rather, there are general trends indicating higher mobility among more members of the nomadic group and more local movement among the members of the sedentary groups. Further, there is more similarity between females of all groups than males, problematising the idea that all individuals respond to bone remodeling activity in the same way. The conclusions presented here recommend that more research needs to be conducted on tibial shape variation in Sudan and worldwide using geometric morphometrics, as it presents a more nuanced approach than cross-sectional geometry, and that bone remodeling in response to activity must continue to be explored in light of differences in age, sex, and musculature.