A comprehensive analysis of long bone curvature in Neanderthals and modern humans using 3D morphometrics

• Main Author: de Groote, Isabelle
• Published: University College London (University of London) 2008
• Subjects: 301; Department of Anthropology
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.492700

Since their discovery Neanderthals were described as having a marked degree of anteroposterior curvature of the femoral shaft. Although initially believed to be pathological, subsequent discoveries of Neanderthal remains made femoral curvature as well as the lateral curvature of the radius to be considered derived Neanderthal features. Femoral curvature has previously been used in racial identification in modern humans but its functional significance is poorly understood. A recent study on Neanderthals and early modern humans found no differences in femoral curvature, but did not consider size-corrected curvature. Therefore, the objectives of this study were to 1) use 3D morphometric landmark and semi-landmark analysis to quantify bone curvature (femur, ulna, radius) in Neanderthals, Upper Palaeolithic and recent modern humans, 2) compare adult bone curvature between these populations, and 3) test hypotheses on the effects of climate, body size, and activity patterns on curvature. Comparisons between and within populations were made using geometric morphometries (3D landmarks) and standard multivariate methods. Comparative material involved all available Neanderthal and Upper Palaeolithic modern human femora, ulnae and radii, archaeological (Mesolithic, Neolithic, Medieval) and recent human populations representing a wide geographical and lifestyle range. The study found that there are significant differences in the anatomy of the femur, ulna and radius between Neanderthals and modern humans. Neanderthals have more curved femora and radii than modern humans. Early modern humans are most similar to recent modern humans in their anatomy. Recent modern human analyses indicate that femoral curvature and forearm curvature are responses to disparate influences. Femoral curvature is a good indicator of activity level and habitual loading of the lower limb. Curvature of the forearm is a consequence of cold adaptation and its purpose is to maintain biomechanical function of the forearm despite its foreshortening.