NEUROETHOLOGYBirdsong neurolinguistics songbird context-free grammar claim is prematureBeckers, Gabriël J.L.a; Bolhuis, Johan J.b; Okanoya, Kazuoc,d; Berwick, Robert C.e Author Information aDepartment of Behavioural Neurobiology, Max Planck Institute for Ornithology, Seewiesen, Germany bBehavioural Biology and Helmholtz Institute, University of Utrecht, Utrecht, The Netherlands cDepartment of Cognitive and Behavioral Sciences, University of Tokyo, Tokyo dEmotional Information Joint Research Laboratory, RIKEN Brain Science Institute, Saitama, Japan eDepartment of Electrical Engineering and Computer Science and Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA Correspondence to Gabriël J.L. Beckers, PhD, Department of Behavioural Neurobiology, Max Planck Institute for Ornithology, Eberhard-Gwinner-Straße 6 D-82319 Seewiesen, Germany Tel: +49 8157 932273; fax: +49 8157 932285; e-mail: [email protected] Accepted November 9, 2011 NeuroReport: February 15, 2012 - Volume 23 - Issue 3 - p 139-145 doi: 10.1097/WNR.0b013e32834f1765 Buy Metrics Abstract There are remarkable behavioral, neural, and genetic similarities between song learning in songbirds and speech acquisition in human infants. Previously, we have argued that this parallel cannot be extended to the level of sentence syntax. Although birdsong can indeed have a complex structure, it lacks the combinatorial complexity of human language syntax. Recently, this conclusion has been challenged by a report purporting to show that songbirds can learn so-called context-free syntactic rules and then use them to discriminate particular syllable patterns. Here, we demonstrate that the design of this study is inadequate to draw such a conclusion, and offer alternative explanations for the experimental results that do not require the acquisition and use of context-free grammar rules or a grammar of any kind, only the simpler hypothesis of acoustic similarity matching. We conclude that the evolution of vocal learning involves both neural homologies and behavioral convergence, and that human language reflects a unique cognitive capacity. © 2012 Lippincott Williams & Wilkins, Inc.