To the novice listener, the Australian Chestnut-crowned babbler's sweet melodies may sound like any other birdsong. However, to ornithologists, it is a series of sounds which when combined, forms a unique bird-like vocalization or what we refer to as language. The discovery is exciting because the tiny birds are the first nonhuman species known to communicate using language.
Before exploring the language of the babbler, it is important to define what that means. To most people, communication and language are synonymous. However according to language experts communication or exchange of information can constitute various things - from the aggressive roar of a lion to the incessant buzzing of honeybees - vocal in nature, but not necessarily intellectual.
Language, on the other hand, is the ability to piece together phonemes - distinct units of sound in a specified language that distinguish one word from another. For example, in English, the letters p, b, d, and t could be rearranged to mean several things - pad, pat, bad or even bat.
Over the years, scientists have studied many animals - from zebras to apes and finches. However, they were unable to find any that had figured out communication via language until this tiny bird came along. The research, led by Dr. Andy Russell a behavioral ecologist at the University of Exeter and Simon Townsend of the University of Zurich, identified fifteen distinct calls that the birds make. Two, in particular, were of great interest because they seemed to share similar sounds that had been rearranged.
The first is the “flight” call, that is heard when the babblers are flying over their Australian habitat. It is a short, squeaky sound that the scientists represented as “AB.” The other known as the “prompt” call, is emitted when the birds arrive at the nest to feed their chicks. The three-tiered sound was similar to the first sound except it appeared to prefix with the last sound of the flight call. That means that if the flight call was "AB," the prompt call sounded like "BAB."
After analyzing the two calls, the researchers decided to put them to test by replaying them to the birds. Sure enough, upon hearing the flight call, the babblers looked up expectantly to see if members of their species were flying overhead. The prompt call caused the birds to turn towards the communal nests in the enclosure. “The one syllable [B] by itself seems to differentiate the calls,” said Dr. Russell.
The scientists who published their findings in the journal PLOS ONE on June 29 are still puzzled about one thing. Why did the babblers decide to communicate using this primitive language instead of belting out complex constantly changing songs like other birds? Professor Russell speculates that the smart birds figured out that rearranging sounds that were already in their repertoire to mean different things was easier than coming up with new songs! Gives a whole new meaning to being a "birdbrain" doesn't it?
Resources: latimes.com, independent.co.uk.