Because of their prevalence in the archaeological record, chipped stone assemblages have long been used for the identification of social entities and the tracing of cultural relationships through space and time. To do this, archaeologists have focused primarily on variations in lithic morphology. Although the forms of stone artifacts are determined by a combination their utilitarian function, 'style', and the physical constraints of knapping different cryptocrystalline rocks, there is widespread belief that style provides the best information about social group membership. Style, however, is not a unified concept, including both passive variability resulting from stochastic processes and actively encoded social information, constrained by selection and manipulated by the makers and users of artifacts.
A neo-Darwinian framework is used to evaluate differing concepts of style and their applicability to the lithic archaeological record. Identifying prehistoric social entities and tracing cultural relationships is loosely analogous, methodologically and theoretically, to identifying taxa and tracing ancestor/descendant relationships in biology. Lithic technology is also examined from the point of view of neo-Darwinian evolutionary theory to identity sources of morphological variability most likely to mark group social identity, and suggest methodologies best able to identify and differentiate prehistoric social groups.