Temporal Patterns of Skeletal Trauma Among Native Americans in Prehistoric Central California

Abstract

ABSTRACT TEMPORAL PATTERNS OF SKELETAL TRAUMA AMONG NATIVE AMERICANS IN PREHISTORIC CENTRAL CALIFORNIA by Nikki Ann Willits Master of Arts in Anthropology California State University, Chico Fall 2010 This thesis examines temporal patterns of traumatic injury among the prehistoric inhabitants of central California to ascertain whether they correspond to hypothesized behavioral changes associated with resource intensification. Debates concerning the relative importance of various faunal and floral species to the diet of prehistoric Californians have continued for decades, as various models of subsistence have gained precedence. Particular debate has centered around the importance of acorns and their subsequent effects on the culture and biology of native peoples. Whether or not the acorn is the lynchpin of the argument, archaeological and bioarchaeological data indicate a change in subsistence patterns during the Late Holocene that had consequences for population levels, mobility, and health. This research utilizes patterns of traumatic injury in the form of skeletal fractures and embedded projectiles to test models of resource intensification and the xii division of labor during prehistory. Changes in mobility, resource availability, and social organization due to intensification and a sedentary settlement pattern suggest males and females should both show an increase in the prevalence of trauma through time due to both violent and accidental injuries. Furthermore, males should be more likely to exhibit injuries based on modern clinical and bioarchaeological data. The sexual division of labor also likely became more defined through time with decreased mobility and reliance on a variety of more stable food sources. Of the 176 individuals examined for this research, 36 show evidence of 40 traumatic injuries, including 38 fractures and two embedded projectiles. Comparisons of trauma prevalence by time period, sex, and anatomical element do not support the expectations of resource intensification models. No significant temporal patterns are found in overall trauma for the sample or between males and females. Both sexes show a relatively consistent level of trauma through time. There is no anatomical difference in injury location between males and females, except for trauma to the ulna. Females show a 9:1 ratio of ulnar trauma compared to males. The age distribution and risk for ulnar trauma is greatest during youth and young adulthood, when accident is the most common cause of skeletal injury. Temporal patterns show an increase in ulnar fracture between the Early and Middle Period, followed by an absence in the Late Period. This pattern is inconsistent with expectations of resource intensification during the time; however, they do suggest a temporal change in female activity. Further research is needed to test more direct relationships between trauma and activity patterns among prehistoric peoples of central California through time.