Michael Pleyer

Two central questions regarding the evolution of language are a) how representations of linguistic structures first emerged in individuals and b) how emergent linguistic structures spread throughout communities and became conventionalised. The concept of “protolanguage” (Tallerman 2012) is often evoked to bridge the gap between fully linguistic, complex linguistic structures and an earlier stage of structured communication. However, questions a) and b) hold for the evolution of protolanguage just as much as they do for fully complex modern language. This paper discusses two important factors and their potential for shedding light on these two questions from a usage-based perspective: entrenchment and conventionalisation. In highlighting the importance of these two factors, this paper follows models of the emergence of structure on the individual and community levels, such as the Entrenchment-and-Conventionalisation Model by Schmid (2020).
First, regarding the level of individuals, the process of entrenchment is central to how structures emerge, are represented, and are stored in the minds/brains of individuals. Frequently occurring structures become entrenched in memory. Increasing frequency leads to strengthening of these stored structures and to stronger entrenchment in memory (Langacker 1987; Divjak 2019; Schmid 2016; Blumenthal-Dramé 2012). Entrenchment has a number of cognitive effects, such as entrenched structures achieving higher rates of automatization and easier activation of these memory structures (Neels 2020). In addition, entrenched structures that often co-occur together acquire unit status by becoming associated with each other through usage. With sufficient frequency, these structures also undergo chunking, leading to the emergence of fused structures (Bybee 2010, Divjak 2019). Entrenchment and its associated effects have been implicated in the emergence of structure in both language learning (Schmid 2016) and language change (Hilpert 2017; Neels 2020), and they also have wide-ranging implications for how structures first emerged in individuals to give rise to protolanguage(s), and how protolanguage(s) transformed into modern human language(s).
Secondly, conventionalisation refers to the establishment and diffusion of community-wide, regularised practices (Schmid 2020). Processes of conventionalisation depend on processes of social transmission interacting with individual processes of entrenchment, and as such represent an important part of explaining of how communicative structures came to be adopted both in protolinguistic and linguistic communities. Conventionalisation also represents the foundation for cumulative cultural evolution (Tomasello 1999), which enables the cumulative accretion of
changes and increasing structuration of communicative systems. This in turn enabled the gradual change from protolanguage to modern human language (Heine & Kuteva 2007).
In summary then, the present paper will present entrenchment and conventionalisation, as well as their underlying mechanisms, as crucial building blocks of a usage-based approach to the evolution of language.

References
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