Coevolutionary Approaches to the Science of Language

Since the famous exchange of letters between Darwin and Schleicher, the parallels between evolutionary processes in the biological and linguistic spheres have been evident. In this paper, I present a coevolutionary approach to language evolution, both in the early phase during which hominins evolved language and in subsequent phases during which humans evolved many thousands of languages whose vastly differing structures serve as a basic resource for understanding the operation of evolutionary processes on languages and cultures. The key elements in this coevolutionary approach are (a) the adoption of a gradualist approach to initial language evolution and (b) the recognition of a large number of selectors (systemic, modality, demographic, usage patterns, biogenetic, epidemiological, sociocultural) which are unevenly distributed across speaker populations and which may nudge emerging languages structures into quite different parts of the design space. Not only does the coevolutionary approach presented here bring the methods of studying linguistic evolution closer to those used in biology, it places the phenomenon of diversity and variability—diversity at the level of differences between languages, and variability between how individuals use them—into the same central role that these occupy in evolutionary biology.