Modeling Cultural Transmission in Structured Populations Raises Important Questions for Archaeologists

Abstract

Paleolithic archaeologists study regional variation among assemblages of stone tools in order to delineate cultural boundaries and reconstruct mechanisms of cultural transmission in the deep past. Structured population models are especially suited to aid in this endeavor, for they teach us how cultural evolutionary forces—copying error, intergroup transmission, drift, and selection imposed by functional constraints or biased cultural transmission—affect regional cultural variation. We use an agent-based model to address how copying error, intergroup transmission, and time-averaging affect the degree to which regional archaeological assemblages differ at a selectively neutral discrete trait passed from “experienced” to “naïve” individuals via one of four mechanisms of cultural transmission in a structured population of toolmakers. The results of our simulation experiment illustrate why researchers who use time-averaged archaeological data to identify past cultural boundaries or infer mechanisms of cultural transmission should be more mindful of the nature of the cultural trait(s) available for study. In light of our results, we discuss seven questions archaeologists ought to address before attempting to infer cultural boundaries or cultural transmission mechanisms from between-assemblage variation.