Relation to past glaciation � 9 Geography� 12 Homer area� 46 Geomorphology� 12 Coastal-bog stratigraphy and fauna � 47 Nikishka Lowland �

Archaeological and paleoenvironmental data are integrated in an investigation of culture change among the Anasazi of the American Southwest by a conceptual model of the interaction among environment, population, and behavior, the major determinants of human adaptive systems. Geological, palynological, and dendrochronological reconstructions of low and high frequency environmental variability coupled with population trends are used to specify periods of regional population-resource stress that should have elicited behavioral responses. Examination of these periods elucidates the range of responses employed and clarifies the adaptive contributions of mobility, shift of settlement location, subsistence mix, exchange, ceremonialism, agricultural intensification, and territoriality. These results help differentiate responses that are triggered by environmental variability from those stimulated primarily by demographic or sociocultural factors. These analyses also demonstrate the adaptive importance of amplitude, frequency, temporal, spatial, and durational aspects of environmental variability compared to the commonly invoked but simplistic contrast between “favorable” and “unfavorable” conditions.

Convergent archeological, geological, palynological, dendrochronological, and radiometric data provide a paleoenvironmental record for the American Southwest at a level of detail and time resolution not previously achieved. Many prehistoric cultural and demographic changes on the Colorado Plateaus coincided with environmental fluctuations defined by precisely dated geoclimatic and bioclimatic indicators. These coincidences support the interpretation that socioeconomic changes and population displacements were commonly triggered by environmental stress.