The common European starling has recently been found to possess grammatical capabilities (or something analogous) that were once believed to be the factor that made human language unique.

According to an article in the most recent edition of Nature, a group led by Timothy Q. Gentner, from the Organismal Biology and Anatomy department at the University of California, San Diego, found that the starlings could be taught to recognize complex 'recursive' structure. In human language, this is the insertion of words or clauses into the middle of a sentence. The Nature article illustrates with the example "the paperback [on the coffee table] is hilarious," where the bracketed phrase is the recursion.

Here's a description of the experiment from Nature:

The AnBn language... is generally assumed to be recursive because new sentences can be formed by successive insertion into the frame AXB, for example AB, AABB, AAABBB and so on. Gentner and colleagues rewarded European starlings for pressing a bar in response to AnBn strings of starling-generated sounds, such as rattle rattle warble warble, and withheld the reward for responses to the (AB)n grammar (and vice versa for another group of starlings). Although learning was not instantaneous, nine of eleven birds eventually (after 10,000–50,000 trials) learned to discriminate reliably between the two grammars... An extensive series of control comparisons strongly suggests that the ultimately acquired grammar is robust.

"It's tempting to summarize the differences between humans and other species in a concise phrase," Gary F. Marcus writes in an article introducing the findings in Nature, "but most posited differences have turned out to be overstated."

According to the web magazine LiveScience, Noam Chomsky, one of the major proponents of the unique-to-humans view of the matter, does not believe that the new study carries much weight.

"The article is based on an elementary mathematical error," said Chomsky, professor of linguistics at Massachusetts Institute of Technology. "They are overlooking the fact that there are many intermediate systems that are ignored in mathematical linguistics because their properties are empirically irrelevant."

"It has nothing remotely to do with language; probably just with short-term memory," Chomsky told LiveScience.

But last night, I met a lingustics student in a karaoke bar, and he said it sounded convincing. Then he got up and sang the Zombies' song, "She's Not There."