The evolutionary-emergence model of language change
The model of language change sketched here – the evolutionary-emergence model – takes the position that language is an <i>emergent system</i> within which language change can be modeled as an evolutionary process applied to the emergent properties of that system. Describing language as <i>emergent</i> entails that the complexity of the linguistic system is built out of smaller simple processes. Though theories of language change are often juxtaposed in opposition to one another, the approach taken here shows that each may be considered correct, at least in part, once the separate roles and expectations for speakers and hearers are disentangled. After sketching the evolutionary-emergence model of language change in terms of previous models of language change, data taken from “emerging adults” living in a dialect transition-zone are described within the framework of evolutionary-emergence model. The data under consideration are the TRAP, LOT, and THOUGHT vowels, specifically, the relationship of TRAP-retraction to the LOT/THOUGHT merger. The data presented here show that while the presence of TRAP-retraction and LOT/THOUGHT merger are positively correlated at the community level, there is no need to find this correlation at the level of individual speakers.