Geoarchaeology and the Search for the First Americans

Dr. Vance T. Holliday

Professor of Anthropology & Geosciences

Director, Argonaut Archaeological Research Fund

University of Arizona

Research into the origins and subsequent development of the first American cultures (“Paleoindians”) raises questions that are fundamentally geoscientific. Many of the answers, therefore, have come from geography, geology, and soil science, and at a wide range of spatial scales. Stratigraphy, perhaps the most basic principle in both archaeology and geology, first established the antiquity and chronology of the earliest artifact assemblages at sites such as Folsom and Clovis in New Mexico by demonstrating clear association of artifacts and Pleistocene fauna. Many Paleoindian sites also yielded not only extinct fauna, but stratigraphic records with evidence of markedly different depositional environments in the past. The ancient fauna and the striking contrasts between past and present depositional environments drew the attention of archaeologists and earth scientists alike who recognized the paleoenvironmental implications. At broader spatial scales geomorphologists reconstructed the dramatically different surface hydrology of late Pleistocene North America. Large lakes and higher stream discharges dominated the landscape of the First Americans in many areas. At regional, subcontinental scales the peopling of the New World has been a question revolving around lowered seas levels and fluctuating glacier margins. Modeling sea-level changes and the paleogeography of the “Bering Land Bridge” and the high-precision dating of ice retreat over Canada is helping to understand the environmental conditions faced by Native American forbears in Beringia and the environment, route(s), and timing of their entry into North America.