Tuesday, December 4, 2018
Arizona State Museum, Room 309
Title: Intraskeletal Variability in Age-Related Bone Loss in Southeastern Arizona (800 B.C. – A.D. 1900)
Abstract: Studies of age-related bone loss in archaeology provide a valuable tool for understanding past health and behavior, as well as gaining insight into osteoporosis as a modern disease. Previous studies, however, have often reported contradictory results. Some studies have reported past populations experienced lower rates of bone loss compared to modern populations, others higher rates, while further studies found many archaeological samples show similar patterns of bone loss to living peoples. While these conflicting findings are likely due in part to population-specific differences in nutrition, activity, and other factors, they may also be the result of the wide variety of methods used in bone loss studies and fundamental intraskeletal variability. The aim of this dissertation was to address some of these discrepancies in an examination of age-related bone loss and subsistence change in Southeastern Arizona (c. 800 B.C. – A.D. 1900), by adopting a multi-method whole-body approach and incorporating biomechanical analyses. Using pQCT, this study measured changes in density between cortical and trabecular bone, differences in density and strength across a continuum of load-bearing elements, and applied these analyses to skeletal samples spanning 2100 years to better understand the impacts of the development of agriculture. The results demonstrated significant variability in bone loss between skeletal tissues and elements, patterns that further differed between the sexes. Changes in bone density and strength were also found after the introduction of agriculture in higher load-bearing elements, suggesting changes in mobility and physical activity may have been a primary driver of reduced bone density seen in later populations. This project demonstrates the utility of employing a multi-method approach to age-related bone loss studies and sheds new light on the health impacts of the introduction of agriculture in the American Southwest.
Committee: James T. Watson, David Raichlen, Ivy Pike, and Mary Stiner