In the April 27, 2006, issue of Nature, the researchers show that these starlings ?long known as virtuoso songbirds and expert mimics ?can be trained to reliably discriminate between two different patterns of organizing the sounds they use to communicate.
"Our research is a refutation of the canonical position that what makes human language unique is a singular ability to comprehend these kinds of patterns," said Timothy Gentner, assistant professor of psychology at UCSD and lead author of the study. "If birds can learn these patterning rules, then their use does not explain the uniqueness of human language."
The researchers focused on recursion, or center-embedding, a characteristic, found in all human languages. Recursion is one way of creating of new and grammatically correct meanings by inserting words and clauses within sentences -- theoretically, without limit. So, for example, "The bird sang," can become "The bird the cat chased sang."
Following the lead of language theorist Noam Chomsky, linguists have held that this recursive center-embedding is a universal feature of human language and, moreover, that the ability to process it forms a unique computational ability important for human language.
"Linguists have developed a mathematically rigorous set of definitions, a hierarchy of syntactical complexity, that governs the process of how humans create and understand utterances," said Daniel Margoliash, professor of anatomy and organismal biology at the University of Chicago and co-author of the study. "These rules govern how
Source:University of Chicago Medical Center