Language Acquisition from a Biolinguistic Perspective Stephen Craina*, Loes Koringb and Rosalind Thorntona a Department of Linguistics, Macquarie University, Sydney, Australia b Department of Cognitive Science, Macquarie University, Sydney, Australia *Corresponding author at: Department of Linguistics, Australian Hearing Hub, 16 University Avenue, Macquarie University NSW 2109, E-mail address:
[email protected] 1 Abstract This paper describes the biolinguistic approach to language acquisition. We contrast the biolinguistic approach with a usage-based approach. We argue that the biolinguistic approach is superior because it provides more accurate and more extensive generalizations about the properties of human languages, as well as a better account of how children acquire human languages. To distinguish between these accounts, we focus on how child and adult language differ both in sentence production and in sentence understanding. We argue that the observed differences resist explanation using the cognitive mechanisms that are invoked by the usage-based approach. In contrast, the biolinguistic approach explains the qualitative parametric differences between child and adult language. Explaining how child and adult language differ and demonstrating that children perceive unity despite apparent diversity are two of the hallmarks of the biolinguistic approach to language acquisition. Keywords: Biolinguistics; Language Acquisition; Unification; Universal Grammar; Structure- dependence; Continuity Assumption; Usage-Based Approach 2 1. Introduction There are many ways we could start this chapter, but a good place to start is with the Modularity Hypothesis. The Modularity Hypothesis supposes that the human mind/brain is comprised of "separate systems [i.e., the language faculty, visual system, facial recognition module, etc.] with their own properties" (Chomsky, 1988, p.