Babbler Bird Calls "Convey Meaning"

The chestnut-crowned babbler bird (Pomatostomus ruficeps) is a small bird native to Australia. Researchers think that its chirps and calls are radically different from those identified in other birds. The babbler bird vocalizes words. The BBC reports:

Co-researcher Dr Andy Russell from the University of Exeter said: "It is the first evidence outside of a human that an animal can use the same meaningless sounds in different arrangements to generate new meaning.
"It's a very basic form of word generation - I'd be amazed if other animals can't do this too."

Dr. Russell and his colleagues found that the chestnut-crowned babbler makes two distinct sounds, dubbed A and B. Combinations of A and B in different orders seemed to express concepts that other members of the species could understand:

In flight, they used an "A-B" call to make their whereabouts known, but when alerting chicks to food they combined the sounds differently to make "B-A-B".
The birds seemed to understand the meaning of the calls.
When the feeding call was played back to them, they looked at nests, while when they heard a flight call they looked at the sky.