Mutual exclusivity: communicative success despite conceptual divergence

Abstract

Abstract Traditional explanatory accounts of the evolution of language frequently appeal to a ‘conventional neo-Darwinian process’ (Pinker and Bloom 1990: 707), assuming that humans have evolved an innate, genetically encoded language acquisition device, which specifies a formal coding of universal grammar (Chomsky 1965), and which evolved incrementally through a series of steps via natural selection (Jackendoff 2002). An alternative approach focuses instead on the evolution of linguistic structures themselves, as utterances used and understood by speakers and hearers (Christiansen 1994; Croft 2000). Under the latter approach, the continual cycle of expressing and reinterpreting these utterances (Hurford 2002b) drives the cultural evolution of language. Other things being equal, languages which can be readily interpreted and expressed through this cycle are more likely to persist than those which cannot. An explanation of the evolution of syntactic structure is considered to be the Holy Grail of evolutionary linguistics by researchers in both these traditions, because syntax has been seen as the defining characteristic which separates human language from animal communication systems, and in recent years, computational simulations have been used extensively to shed light on this issue. Kirby (2002a), for example, shows that structured signals can develop from unstructured signals through the analysis of signal-meaning pairs and the subsequent generalization of rules based on the analysis; similar accounts are presented by Batali (2002), whose agents combine and modify phrases based on exemplars of signal-meaning mappings which they receive, and by Brighton (2002), who shows how the poverty of the stimulus is an important factor in the emergence of compositional syntax.