Overview: Debating the effect of environment on language

Abstract

If languages do indeed evolve then they must show the three crucial aspects of an evolving system: variation of traits, inheritance of those traits, and the differential survival—that is selection—of those traits (Lewontin 1970). We know that languages vary (otherwise the fields of linguistic typology and sociolinguistics would be boring). We know that variation is passed through speech communities and inherited from parent language to its daughters (otherwise historical linguistics would likewise be boring). However, whether linguistic traits are selected for is much less clear (Ramsey and De Block 2016). Nor is it clear just where selection might operate (Dediu et al. 2013). Despite these issues, many possible candidates for selective effects have been proposed in the linguistic literature. Selection might operate at the level of the speech act . For example, the more lexical items are used, the more stable they are over time, which may be consistent with frequency-dependent selection (Pagel et al. 2007; Calude and Pagel 2011), while the length of these more frequent words appears to be shorter to increase communication efficiency (Piantadosi et al. 2011). Alternatively, perhaps rate of speech is constrained as there …