UC San Diego

Environmental conditions provide significant constraints and opportunities for human behavior. Paleoenvironmental studies are thus an important component of archaeological investigations seeking to understand the organization, development and decline of past societies. This dissertation develops a method of paleoenvironmental research that uses stable isotope analysis of jackrabbit and cottontail (Leporidae) bones to quantify aspects of the landscapes in which they lived. The project then applies the technique to a sample of bones excavated from four archaeological sites in desert ecosystems of North America to obtain information about human-leporid and human environmental relationships through time. Site locations include Pueblo Grande (Arizona, USA), La Ferrería (Durango, Mexico), La Quemada (Zacatecas, Mexico) , and Teotihuacan (Mexico, Mexico). Results are explored across multiple temporal and spatial scales to refine the method and improve our understanding of the long-term dynamics of social-environmental systems within arid and semi-arid landscapes. Results of baseline analyses on modern bones demonstrate significant correlations between stable oxygen isotope values and moisture variables (precipitation and humidity), and between stable carbon and nitrogen isotope values and temperature variables (min, max, and mean temperature), indicating the utility of leporids as paleoenvironmental proxies. Two primary conclusions result from analyses on archaeological specimens. First, results from La Ferrería leporids demonstrate changes through time suggesting a shift towards wetter conditions during the Las Joyas (AD 850- 1000) phase, a period characterized by increasing population and new architectural construction. Importantly, these findings link social development in the region with environmental change. Secondly, results from Teotihuacan demonstrate rising carbon isotope values concomitant with the growth of the city, likely reflecting human modifications to the landscape, and falling carbon isotope values following its sociopolitical collapse. Notably, during the peak of population and complexity of Teotihuacan leporids from the residential complex of Oztoyahualco demonstrate significantly higher stable carbon isotope values than other contexts, supporting previous assumptions that residents there specialized in rabbit management or breeding. By using stable isotope values from jackrabbit and cottontail bones from modern and archaeological contexts, this dissertation improves our understanding of the baseline factors that influence bone isotope ratios and provides new information on the social-environment dynamics of the ancient New World