Exemplar models, evolution and language change 1 ANDREW B. WEDEL The Linguistic Review 23 (2006), 247–274 0167–6318/06/023-0247 DOI 10.1515/TLR.2006.010 c Walter de Gruyter . Abstract Evidence supporting a rich memory for associations suggests that people can store perceptual details in the form of exemplars. The resulting particulate model of category contents allows the application of evolution theory in mod- eling category change, because variation in categorized percepts is reflected in the distribution of exemplars in a category. Within a production-perception feedback loop, variation within an exemplar-based category provides a reserve of variants that can serve as the seeds for shifts in the system over time through random or selection-driven asymmetries in production and perception. Here, three potential pathways for evolutionary change are identified in linguistic categories: pruning of lines of inheritance, blending inheritance and natural selection. Simulations of each of these pathways are shown within a simple exemplar-based model of category production and perception, showing how consideration of evolutionary processes may contribute to our understanding of linguistic category change over time. 1. Introduction Although we all learn about Darwinian evolution in the context of change within biological species, the mechanism of evolution itself is independent of biology. Darwinian evolution is a population-based mechanism of change and 1. I would like to thank Samira Farwaneh, Joseph Salmons, Kenny Smith, Adam Ussishkin and two anonymous reviewers for valuable comments and suggestions. All errors remain mine.