Until recently, many anthropologists assumed that the environment of what is now the southwestern United States shaped the social history and culture of the region's indigenous peoples. Building on this assumption, archaeologists asserted that adverse environmental conditions and droughts were responsible for the disappearances and migrations of southwestern populations from many sites they once inhabited. However, such deterministic arguments fail to acknowledge that local environmental variability in the Southwest makes generalizing about that environment difficult. To examine the relationship between environmental variation and sociocultural change in the Western Pueblo region of central Arizona, which indigenous tribes have occupied continuously for at least 800 years, a research team recently reconstructed the climatic, vegetational, and erosional cycles of past centuries. The researchers found it impossible to provide a single, generally applicable characterization of environmental conditions for the region. Rather, they found that local areas experienced different patterns of rainfall, wind, and erosion, and that such conditions had prevailed in the Southwest for the last 1,400 years. Rainfall, for example, varied within and between local valley systems, so that even adjacent agricultural fields can produce significantly different yields. The researchers characterized episodes of variation in southwestern environments by frequency: low-frequency environmental processes occur in cycles longer than one human generation, which generally is considered to last about 25 years, and high-frequency processes have shorter cycles. The researchers pointed out that low-frequency processes, such as fluctuations in stream flow and groundwater levels, would not usually be apparent to human populations. In contrast, high-frequency fluctuations such as seasonal temperature variations are observable and somewhat predictable, so that groups could have adapted their behaviors accordingly. When the researchers compared sequences of sociocultural change in the Western Pueblo region with episodes of low- and high-frequency environmental variation, however, they found no simple correlation between environmental process and sociocultural change or persistence. Although early Pueblo peoples did protect themselves against environmental risk and uncertainty, they responded variously on different occasions to similar patterns of high-frequency climatic and environmental change. The researchers identified seven major adaptive responses, including increased mobility, relocation of permanent settlements, changes in subsistence foods, and reliance on trade with other groups. These findings suggest that groups' adaptive choices depended on cultural and social as well as environmental factors and were flexible strategies rather than uncomplicated reactions to environmental change. Environmental conditions mattered, but they were rarely, if ever, sufficient to account for sociocultural persistence and change. Group size and composition, culture, contact with other groups, and individual choices and actions were – barring catastrophes such as floods or earthquakes – more significant for a population's survival than were climate and environment.