The ability to rearrange different meaningless sounds to form meaningful messages is one of the things that set humans apart from other animals. Now researchers have found a bird that has some impressive language skills. Scientists studying the chestnut-crowned babbler birds found that these social birds can also string together meaningless sounds in their calls to form meaningful messages.
Other birds produce different sounds, but without changing the meaning
Findings of the study were published in the latest issue of PLOS Biology. These roughly 2-ounce babbler birds live in the Australian Outback. Scientists have known for years that birds have the ability to put together different sounds for the songs their sing. However, these sounds did not hold a meaning, said lead author Sabrina Engesser of the University of Zurich. Simply changing the arrangement of sounds within a song doesn’t alter its message.
However, babbler birds don’t sing. Researchers found that the bird calls had different patterns in certain circumstances. Sabrina Engesser said the study suggests that the capacity to rearrange meaningless sounds to create new signals exists outside of humans. A major question in the evolution of language is that how its generative power emerged. Scientists said it would shed light on the generative phonemic system of human language.
Babbler birds respond differently to different calls
In their experiment, scientists identified two sounds and named them ‘A’ and ‘B.’ Babbler birds combined these two sounds for flight call (AB) and feeding call (BAB). When researchers played the sounds back, birds reacted differently. When they heard the feeding call (BAB), they started looking at their nests. They began looking out for incoming birds when they heard the flight call (AB).
Though the two blabber bird calls are structurally similar, birds produce them in different behavioral contexts and listening birds can pick up on this. Scientists said further research was needed to determine how the babbler birds “compute and perceive the elements from the two calls.”