Introduction

How can we explain the origins of our uniquely human compositional system of communication? Much of the recent work tackling this problem (e.g. Bickerton 1990; Pinker and Bloom 1990; Newmeyer 1991; Hurford, Knight and Studdert-Kennedy 1998) explicitly attempts to relate models of our innate linguistic endowment to neo-Darwinian evolutionary theory. These are essentially functional stories, arguing that the central features of human language are genetically encoded and have emerged over evolutionary time in response to natural selection pressures.

In this chapter I put forward a new approach to understanding the origins of some of the key ingredients in a syntactic system. I show, using a computational model, that compositional syntax is an inevitable outcome of the dynamics of observationally learned communication systems. In a simulated population of individuals, language develops from a simple idiosyncratic vocabulary with little expressive power, to a compositional system with high expressivity, nouns and verbs, and word order expressing meaning distinctions. This happens without natural selection of learners – indeed, without any biological change at all or any notion of function being built into the system.

This approach does not deny the possibility that much of our linguistic ability may be explained in terms of natural selection, but it does highlight the fact that biological evolution is by no means the only powerful adaptive system at work in the origins of human language.

The Origins of Syntax

Pinker and Bloom (1990) argue that an analysis of the design features of human language, and of syntax in particular, leads to the conclusion that the best way of understanding their origins is as biological adaptations.