ABSTRACT
This chapter is about language evolution as applying to changes that a language has undergone in its life regarding its structures, its pragmatics and its vitality (viz. whether it is endangered, dying or thriving). With languages conceived of as the counterparts of viral species (whose lives depend on the agency of speakers), I articulate various dimensions of the external and internal ecologies that are particularly significant. I focus on the feature pool and the competition and selection that arise from it and on the role of especially population structure and timespace as critical factors determining the evolutionary trajectories of languages.
