This story about research that appears to show that birds can learn "grammar" was of particular interest to me because I am currently reading Nicholas Wade's new book on the prehistory of mankind, "Before the Dawn: Recovering the Lost History of Our Ancestors." One of the points that Wade hammers home is that no matter how many words we claim to have taught primates in sign language (and he is skeptical of many of the claims of large vocabularies), what they know cannot be termed "language" because there is no grammar or syntax. He notes that certain chimps have different sounds to indicate attacks by predators from the air or the ground, but, again, this is not language because it cannot be re-arranged to convey different meanings in the way that human languages can.
Now, the mainstream media has an abysmal record in science reporting, so I will have to track down the Nature article to see what the actual experiment was, but it would be fascinating to learn that non-primates have a linguistic ability that non-human primates do not. Hauser himself points to a possible explanation, when he notes that the studies he has done with primates have been structured to see if they recognize grammar, not to try to train them to understand it.