1Department of Anthropology; Labratories of Molecular Anthropology and Microbiome Research, The University of Oklahoma, 2Department of Anthropology, Fort Lewis College
March 27, 2015 , Archview Ballroom
Histological studies of bone represent an effective means of reconstructing health and estimating age in ancient populations through frequency and size analyses of osteons. Although secondary osteons have been studied extensively, double-zonal osteons are atypical and are not entirely understood. Previous research suggests that double-zonal osteons may represent periods of growth arrest due to physiological stress. In this study, rib thin sections from 51 individuals, between ages 15-50+, from medieval Kulubnarti, Nubia were examined to assess whether double-zonal osteon frequencies vary with age and sex.
Thin sections were observed using a compound light microscope. Frequencies of double-zonal osteons were counted for each rib section. Section areas were determined using Image J. Results show that double-zonal osteons demonstrate a strong, significant negative correlation with age (Spearman’s rho= -0.572; p= .000). A Mann Whitney U test showed no statistically significant difference between the sexes (p= 0.118). The negative correlation with age for double-zonal osteons is particularly interesting given the pattern of an overall increase in osteons with age. Previous research on the Kulubnarti sample has demonstrated the presence of generalized stress. Double-zonal osteons decrease with age, supporting the hypothesis that they represent periods of growth arrest, as individuals with more double-zonal osteons appear to have a higher risk of dying. However it is unclear whether the patterns suggested by this study are population or bone-specific. Future histological studies will incorporate data from other elements and other skeletal samples.