Human Response to Long Term Climate Change

New York University, New York NY

Investigators

Abstract

The goal of this project is to investigate the impact of extreme cold and arid climatic conditions on ancient humans. Aridity is an important element of current human-induced changes in our climate, affecting large parts of the populated world. Initially ignored by scientists and policymakers, the ways in which mobile, small-scale societies adapted to such environmental changes in the past have proven insightful for designing solutions for the future. The deep past offers multiple examples of arid events, but few are extreme enough or lasted sufficiently long to act as likely drivers of large-scale changes in human behavior. One such event is the Last Glacial Maximum (LGM, 26-19 thousands of years (ka) ago), a cold and dry period that lasted for several millennia and provoked large worldwide ecological shifts. Hunters and gatherers of that time either abandoned the affected regions or survived in one of two possible ways: by finding local refugia where conditions were milder or, alternatively, by adapting to the increasingly challenging environments through innovations in technology, subsistence, and land-use. Each of these possibilities offers a different piece of the puzzle of human adaptation to climate change and the present research will help decide between these alternatives using archaeological data. The project will also serve as a training platform for American and local students and as a vehicle for archaeological conservation and education efforts. The PI excavates a recently discovered archaeological site, which preserves a unique record of human presence at the height of the climatic deterioration associated with the LGM. The team combines a larger-scale excavation with studies of fossil plants and animals to understand local responses to global climate change, as well as the diversity of sources of food and fuel available to humans during this period. In particular, the spectrum of plants are compared with the charcoal remains to study which plants humans picked for making fires inside the cave, an important adaptation to the cold. The scientists analyze the spatial distribution of exploited stone raw materials, which can reveal how ancient people moved through the landscape and how they organized their technologies. Together, these analyses will reveal the role of risk minimization and mobility as behavioral responses to falling temperatures and intensifying aridity. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.