Modeling Prehistoric Health in the Middle Cumberland Region of Tennessee: Mississippian Populations on the Threshold of Collapse

This research explores differences in mortality and survivorship resulting from factors associated with the abandonment of the Middle Cumberland Region (MCR) of Tennessee during the Mississippian period (ca. 1000-1500 AD). My dissertation investigates whether individuals from the Late Mississippian period had a greater risk of death than individuals from the Early Mississippian period. Adult age-at-death estimates (n=545) were calculated using Transition Analysis, a Bayesian maximum likelihood method. Gompertz and Gompertz-Makeham hazard models were utilized to reconstruct the mortality profile of the MCR as they model human adult mortality and generate robust parametric mortality profiles. Rather than recount the prevalence of disease conditions, this project uses MCR skeletal data to understand the biological, social, and ecological processes that positioned some individuals in the community with a greater risk of death than others. To this end, biological markers of childhood physiological stress and poor dental health, skeletal evidence of warfare-related trauma, and paleoclimate data were analyzed as health co-variates in a series of Kaplan-Meier survival analyses and log-rank tests.

The paleodemographic results suggest that survivorship did not simply decrease with age. Marked differences between the sexes indicate that females had increased mortality compared to males. Survivorship of males decreased sharply from the Early Mississippian to Late Mississippian period, possibly due to elevated rates of conflict. On the whole, mortality was elevated in the Late Mississippian period compared to the Early Mississippian period. Paleoepidemiological results demonstrate that risk of death was not uniform across the MCR during the Mississippian period. While some findings support traditional interpretations that the presence of certain conditions (porotic hyperostosis, carious lesions, skeletal trauma) had a negative impact on survivorship, results for linear enamel hypoplasias, dental abscesses, and antemortem tooth loss offer support for the osteological paradox.