Although archaeology has a long history of interest in environmental and cultural relationships, only the most recent project designs and field techniques have begun to allow for the complexity involved in an ecological approach to past behavior. Ecology is the study of dynamic relationships between organisms and their total environments. An ecological approach to cultural behavior requires, consequently, that any particular aspect of behavior be examined within its cultural and natural context, keeping in mind that this context may be varying in space and time. With the realization that past behavior must be explained, in part, in relation to its context, the concept of the ecosystem, as the structure of dynamic interrelationships of population behavior and its context, has emerged as important in archaeological method and theory.