1991). The investigation focused on the relationship between particular aspects of Nunamiut behavior and the material record these people were creating, rather than relying on descriptions they provided about the activities in which they were engaged. Binford found, for instance, that there were no simple relationships between assemblage composition and site function, even though the artifacts that accumulated at different sites exhibited patterns that archaeologists could detect. The form and design of artifacts, their functions, and the extent to which they were reused varied, depending on the way that resources in different parts of the landscape were employed. Thus, Binford showed that explanations for the similarities and differences in the composition of artifact assemblages were likely to involve a complex series of cause-and-effect statements integrating aspects of technology, the strategies used to acquire resources, and patterns of movement across the landscape.

More recently, archaeologists interested in the problem of technological organization have begun to draw on the theories and methods of evolutionary ecology. This approach involves an application of the ideas explored in recent decades by evolutionary biologists with the aim of understanding the extent to which evolution shapes behavior—in other words, to assess the role that specific behaviors play in the survival and reproductive success of individual members of a social group. Archaeologists employing the principles of evolutionary ecology have sought to establish a link between the way in which artifacts were made and used and the exploitation of specific items contributing to the diet. For example, the acquisition of raw materials, the fashioning of these into tools, and the use, maintenance, and discard of the tools have been analyzed and interpreted in the same way as other behaviors—it is assumed that natural selection will have played a role in shaping the stone technology employed by a particular group of people to gain access to particular resources.

As in studies of foraging behavior, attempts to adapt the theory of evolutionary ecology to stone technology involve a cost-benefit analysis based on the assumption that, all other things being equal, natural selection will have created the optimal solution to an adaptive problem. However, nothing is ever truly “equal,” and the purpose of the cost-benefit analysis is not to identify the optimal technological solution with respect to a particular problem. Rather, the aim is to identify the optimal strategy identified on theoretical grounds, to compare it with the actual strategy employed, and to seek an explanation for the differences between the two. For this reason an optimization model provides archaeologists with a heuristic device rather than an analytical tool.

Given the difficulties of identifying the actual costs and benefits of different technological strategies employed in the past, archaeologists have tended to use qualitative methodologies to assess the relative costs and benefits of different types of technologies. A number of researchers (such as R. Torrence) have explored the concept of risk and the ways in which technology could be used to reduce the probability that the costs incurred in the capture of a specific item of prey would exceed the benefits associated with its capture. Risks are assessed in terms of the consequences of failing to access a specific resource, and inferences are made about the suitability of different artifacts for acquiring that resource. It is assumed that the artifacts used to acquire specific prey items have to be available and in good working order at the precise moment that the prey is captured. It is further assumed that the time and resources expended in developing technologies that would ensure the capture of a particular prey item are proportional to the consequences of failing to acquire it. The prey items associated with the greatest risk are those that are mobile and available only at one location and only for a short period of time. In such situations more time and effort would be expended in making the artifacts needed to exploit these types of food sources than in making artifacts used to capture sedentary food sources available throughout the year.

M. Nelson (1991) and others have built on these ideas to try to characterize different types of stone technologies and the types of foraging strategies for which they are most likely to have been employed. In these studies curated, expedient, and opportunistic technologies are distinguished