Pinker, S., & Jackendoff, R. (2005). The faculty of language: what's special about it? Cognition, 95(2), 201-236.

We examine the question of which aspects of language are uniquely human and uniquely linguistic in light of recent suggestions by Hauser, Chomsky, and Fitch that the only such aspect is syntactic recursion....... We find the hypothesis problematic.......
It is inconsistent with the anatomy and neural control of the human vocal tract. And it is weakened by experiments suggesting that ...... at least one gene involved in speech and language was evolutionarily selected in the human lineage but is not specific to recursion..... We contest related arguments that language is not an adaptation, namely that it is "perfect," non-redundant, unusable in any partial form, and badly designed for communication. The hypothesis that language is a complex adaptation for communication which evolved piecemeal avoids all these problems. (C) 2004 Elsevier B.V. All rights reserved.