Heather Chamberlain-Irwin

This interdisciplinary research project employs a novel analysis of ancient DNA to reveal the temporal dimension of maize evolution and adaptation. Given the dependence of maize on humans, I propose using ancient maize genomics as a proxy for understanding practices of state expansion by tracing highland and lowland traits over eras of occupation. The study region of Moquegua Valley has 3000 years of documented maize cultivation (Blom et al. 1998; Goldstein 2005). The archaeological record reflects floodplain subsistence (Initial and Early Horizon periods) and intensified farming using irrigation canals under the long duration of Tiwanaku colonization (Late Early Intermediate and Middle Horizon periods) (Hastorf et al. 2006). Specifically, I use the lens of ecological imperialism (Crosby 2004) to interrogate how colonization of the Moquegua Valley by highland people of the expansive Tiwanaku state changed maize genetic diversity and population structure. My research goals are to 1) assemble a representative genetic panel of modern and ancient maize; 2) directly date ancient maize specimens with accelerated mass spectrometry (AMS); 3) and compare the ancient and modern genomes. The unique combination of anthropological anthropology and maize genetics will provide insight into agricultural tactics of the expansive Tiwanaku state system.