Paleopathological analysis of disease in the pre-colonial Americas

Abstract

Paleopathology is an interdisciplinary field at the intersection of science and the humanities with contributions from archaeologists, anthropologists, biomedical scientists, and historians. Traditionally founded in morphological analysis, the field is experiencing a rise in the application of molecular methods to the study of ancient disease. This provides the opportunity for a greater understanding of pathogen emergence, ecology, evolution and migration, adding value to paleopathological studies investigating medically relevant infectious agents. One such disease is tuberculosis, evidenced to have a long history of human infection and yet currently remains one of the most socially disruptive diseases and leading causes of death. In this thesis, I performed paleopathological analysis to study ancient disease in the precolonial Americas. I applied both morphological and molecular methods to investigate tuberculosis and the genetic history of the tuberculosis causing bacteria, the Mycobacterium tuberculosis complex (MTBC), across North and South American archaeological contexts. One of the presented studies describes the reconstruction and analysis of seven MTBC genomes from Late Intermediate Period (LIP, 1000 – 1400 CE) contexts of the former capital of the Wari empire. While this study provides an evaluation of MTBC strains on a local scale, additional studies in this thesis provide contemporary cases of tuberculosis from a broad geographic sampling representing a variety of environmental contexts. This thesis presents the largest set of ancient MTBC genomes from the Americas to date which reveal key insights to the strain diversity circulating in precolonial populations.