Heather Chamberlain-Irwin

HEATHER CHAMBERLAIN-IRWIN, then a graduate student at Iowa State University, Ames, Iowa, was approved funding in September 2023 to aid research on “Using Ancient Maize DNA to Investigate the Expansion of the Tiwanaku State,” supervised by Dr. Andrew Somerville. This project examines the genetic history of maize in the Moquegua Valley, Peru, using ancient DNA analysis, radiocarbon dating, and morphological measurements to explore how maize evolved alongside shifting social and political landscapes. The study examines maize samples from three key periods: early subsistence farming by the Huaracane people, colonization by the Tiwanaku state, and the post-collapse Tumilaca occupation. The research investigates how genetic traits changed over time and which traits were selected for during state expansion. Using the framework of ecological imperialism, this study assesses how Tiwanaku colonization shaped maize genetic diversity and adaptation. Leveraging the largest ancient maize dataset to date, this interdisciplinary approach integrates archaeology and genomics to provide new insights into agricultural strategies within expansive political systems. The research goals include assembling a representative genetic panel of ancient and modern maize, directly dating ancient specimens with accelerated mass spectrometry (AMS), and comparing ancient and modern genomic and morphological traits to track evolutionary change. By examining maize as a proxy for human agricultural practices, this project contributes to broader discussions on the relationship between state expansion, environmental adaptation, and crop domestication in ancient Andean societies.