The Cultural Evolution of Language

Abstract Language is one of only a handful of human cultural systems that is both unique to our species, and universal. This chapter will focus on the cultural evolution of language, situating this alongside the phylogenetic and developmental timescales which also feed into the evolution of language. The chapter begins by outlining the relationship between the emergence of human language and the language faculty and the more rapid, ongoing processes of language change, which are often framed as predominantly cultural. In particular, previous work has emphasized how these timescales interact, and how cultural factors in particular shape which aspects of language exhibit broad cross-cultural variation or stability. This is followed by detailed evidence for this relationship from three domains, focusing on the role of cultural evolution in language as observed in natural language (both historical corpora and cross-linguistic data), the cultural evolution of language in agent-based models, and finally, experimental studies of the cultural evolution of language. The chapter concludes that the study of the cultural evolution of language forms an important data-rich model for the study of the evolution of cultural systems more generally, while also providing key insights into the specific dynamics of this uniquely human behaviour.