A cross-population analysis of the growth of long bones and the os coxae of three Early Medieval Austrian populations

Inter-population variability in long-bone and pelvic-bone growth during the Early Medieval period is examined. The materials comprise four archaeological populations: two Slavonic (Gars–Thunau, Zwentendorf, Austria, 10th-century ad), one Avar (Zwölfaxing, Austria, 8th-century ad), and one Anglo-Saxon (Raunds, England, 10th-century ad). Bone measurements are analyzed against dental age estimates in order to assess inter-population differences in growth rates for long-bone and os coxae bone dimensions. Growth curves of the upper and lower extremities of additional archaeological populations and a modern North-American population are also assessed. The expectation was that the greatest differences in growth patterns would be found between the Anglo-Saxon and the Austrian samples, due to their distinct genetic and biocultural background. Minimal differences were expected between the two Slavonic populations, as these were approximately contemporaneous, recovered from geographically close locations, and shared relatively similar archaeological contexts. Growth curves were estimated for each bone dimension by fitting least-squares fourth-order polynomials (which allowed testing of population differences by analysis of covariance), and iteratively estimating Gompertz growth curves. The results showed differences between bones in the extent of inter-population variability, with diaphyseal long-bone growth showing equivalent patterns across the four populations, but significant differences between populations in the growth patterns of distal diaphyseal dimensions of the femur and humerus and the dimensions of the ilium. Varying growth patterns are therefore associated with inter-population differences in absolute dimensions in relation to age as well as variations in growth velocities. Inter-population variability in growth curves in the case of femoral and humeral dimensions were most pronounced during infancy (0–2 years). The most consistent differences in bone growth and related dimensions are between Zwölfaxing and the other samples. No significant differences in growth were detected between the Anglo-Saxon and the Austrian populations.