DOI: 10.7274/29566088.v1
title: Macaws to Mushroom Clouds: People, Things, and the Planetary History of an American Borderland

description: According to the stratigraphers, Earth System scientists, and other members of the Anthropocene Working Group (AWG), Earth is now in a new geological epoch: the Anthropocene. The Anthropocene is a proposed chronostratigraphic time period that begins in the mid-twentieth century when human activities pushed various Earth System processes beyond Holocene norms. Using northern New Mexico as a case study, this project investigates the Anthropocene’s origins and examines how people in a remote American borderland joined other humans around the globe to bring about an end to the Holocene in the twentieth century. It traces some of the roots of the Anthropocene through six and half centuries of history in the New Mexico borderlands, beginning with the late-thirteenth century development of the first large-scale sedentary communities along the northern Rio Grande and concluding with Earth’s first nuclear detonation at Alamogordo Air Base on July 16, 1945. Along the way, it engages various arguments for pre-twentieth century start dates for the Anthropocene as it connects ancestral Pueblo history, the rise and fall of European and Indigenous powers, the globalization of New Mexico’s borderland communities and economies, and the construction of telegraph lines, railroads, and a secret state laboratory in the region to the origin story of the Anthropocene. In doing so, this project provides a regional accounting of the Anthropocene’s origins filled with particular people and the decisions they made in a complicated borderland—an approach to Anthropocene history that provides a needed contrast to much existing work focused either on Homo sapiens writ large or Europeans as primary actors. 
As New Mexico’s Anthropocene history reveals, the formation of the global network through which humans ultimately drove the Earth System into a new and largely irreversible condition by the mid-twentieth century depended heavily on the capacity of people to solve local predicaments and build secure and resilient social and political systems on the ground. Across the past six and half centuries, people who lived along the Rio Grande turned to religion, global trade, capitalism, and violence in various forms as they sought to manage the challenges of living in an arid and unpredictable region in Holocene fashion by attempting to warp the world to suit their needs without transforming the planet. In the mid-nineteenth century, however, the United States offered people in New Mexico a new approach to managing both environmental and political predicaments through a potent combination of violent conquests of powerful equestrian Indigenous groups and the introduction of fossil-fueled transportation networks. As this project shows, American conquest paved the pathway out of the Holocene in the Southwest. This claim adds a complimentary American Western perspective to Anthropocene histories attentive to the significance of conquest, showing how modern state conquest wove people in a remote American borderland into the planetary history of the mid-twentieth century Holocene-Anthropocene transition.