Evolution Has Stopped?! Agriculture's Impact Over 6150 Years on Lower Limb Skeletal Biomechanics

Lower limb skeletal biomechanics track long-term decline in mobility across ∼6150 years of agriculture in Central Europe

Authors:

Macintosh et al

Abstract:

Central Europe is a region with a rich agricultural history that dates back to the emergence of the first Neolithic cultures here during the second part of the 6th millennium BC. The effects of prolonged cultural change on the skeletal morphology of agricultural populations in this region have not yet been fully reported. This study investigates diachronic trends in lower limb cross-sectional geometry among preindustrial Central Europeans spanning over 6000 years from the initial spread of agriculture in the region (∼5300 cal BC) to the Early Medieval (∼850 AD). Midshaft diaphyseal cross-sectional geometric (CSG) properties were derived from 443 three-dimensional laser scans of femora and tibiae. Results documented temporal change that was particularly pronounced in the tibia relative to the femur, indicative of declining compressional strength (males), bending and torsional rigidity (males), and increasingly more circular cross-sections (both sexes). When examined chronologically by cemetery, a major shift towards lower tibial rigidity was identified in the Late Bronze Age among males, after which time sexual dimorphism also declined. Regional variation in tibial rigidity was identified among males, being consistently low in males from modern-day Vojvodina (Serbia) relative to contemporaneous males elsewhere in Central Europe. In contrast, female temporal trends by cemetery were indicative of progressive but gradual declines in tibial loading. Results report systematic change in lower limb cross-sectional geometry among preindustrial Central European agriculturalists that are likely indicative of declining terrestrial mobility through 6000+ years of cultural change in the region.