Most animals develop their vocal communication signals, whether grunts or squeals or calls, through trial and error: If it gets the message across, use it again. But some species of birds, like humans, are different. Their young learn through mimicry, that is, by imitating the sounds made by their elders.
From a neurobiological standpoint, this process is complex, as it requires an individual not just to create a sound, but also to interpret the results—to hear the sound, decide whether it is right or wrong, and tweak the process the next time. Such learning through mimicry allows regional populations of the same species of bird to develop the equivalent of "accents," says Richard Mooney, an associate professor of neurobiology.
In a recent study of swamp sparrows, Mooney identified a specific set of neurons that appear to play an important role in the auditory feedback loop in the birds' brains. The neurons fire in similar patterns when a bird sings its own song and when it hears another bird singing the same song.
November 30, 2008