The Calculus of Self Interest in the Development of Cooperation: Sociopolitical Development and Risk among the Northern Anasazi

One clear trend that can be discerned in the last 15 years of otherwise-rather-protean Southwestern archaeology is a growing recognition that at any given time, demographic productive, and organizational strategies can be quite variable, even within comparatively small regions; that these strategies could change quickly and in ways that are not easily predictable through some linear model of process; and that there was perhaps a greater amount of expedient behavior implied by these kinds of variability that had previously been acknowledged (see, for example, Cordell and Plog 1979). This recognition, perhaps, is part of the process of normal science, which first emphasizes understanding the most obvious patterns in time and space---as exemplified for the Anasazi by the Pecos classification---and only then, on understanding the reasons for the variablity that remains, unexplained and initially even undescribed, around those modes. In any case, we have moved from an almost complete focus on mean, or normative, behavior to a greater concern with variability around those norms.