Doctoral Dissertation Improvement Award: The Influence of Resource Availability on Territoriality

Yale University, New Haven CT

Investigators

Abstract

Ecological conditions play a major role in shaping land use and settlement system decisions across all human societies. Prior ethnographic and archaeological research indicates that among hunter-gatherers abundance and predictability of food resources mediate how often and how far groups move, and if they maintain a defended territory. Recent ancient DNA work has shown that by the end of the last glacial cycle , foragers in eastern and southern-central Africa that had once had widespread biological interactions began to live in small groups with little genetic exchange. Local ecological conditions may have been instrumental in shaping patterns of hunter-gatherer interactions, but researchers lack long-term data on how foragers adapted their land use systems to environmental change in this region. The researchers will investigate how the distribution of game animals varied seasonally over multiple millenia and how this affected hunter-gatherer land use as inferred from the archaeological record. The position of the study area in the tropics makes it especially important to reconstruct rainfall seasonality through time, which depends on millennial-scale changes in the position of the Earth relative to the sun and has enormous impact on local plant and animal communities. This project will provide a better understanding of the factors influencing collective decision-making in small-scale societies when they are confronted with novel ecological conditions and link these factors to changes in social interactions. This knowledge will also provide a conceptual framework to understand changes in lifeways as traditional societies around the world are impacted by climate change. The researchers will investigate the link between ecology and land use through the lens of the Economic Defendability Model, which posits that when resources are abundant and spatiotemporally predictable human groups will tend to establish stable territories. Specifically, they will test the hypothesis that these conditions were met after the Last Glacial Maximum with the onset of the modern monsoonal regimen. They will collect zooarchaeological, biogeochemical and chronological data from four rockshelter sites. Archaeological animal remains will provide information about which species were hunted at different times in the past, and how they were transported and utilized in response to territorial behavior. Biogeochemical data will be used to reconstruct ecological conditions, particularly rainfall seasonality (oxygen isotopes), vegetation (carbon isotopes) and animal migration (strontium isotopes). Finally, precise chronological data (radiocarbon dating) will place these proxies on the geological timescale and allow correlations with other paleoenvironmental and archaeological records. 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.