The curious case of Australian birds that “compose” and share their songs

What if birds, besides being great performers, were ingenious composers? A study published in Proceedings of the Royal Society B: Biological Sciences investigated the organization, transmission and function of vocal mimicry sequences sung by male Albert lyrebirds in Eastern Australia.

The birds in question are the male lyres that are able to “compose” long and complex melodies created from imitated sounds that are created in their environment.

Fiona Backhouse, principal researcher of the work and PhD student explained that rhyming at high speed on a rhythmic basis was found that lyrebirds sampled the sounds produced by other birds in their environment and composed new songs by assembling these imitated sounds into very particular sequences.

The research team, which included collaborators from Cornell University, the University of Wollongong and the Australian National University, said the results provide evidence that higher-order mimicry sequences can be transmitted socially and that the order of vocal units can be functionally meaningful.

Many species of birds organize their songs in sequences, but little is known about the drivers of that sequence structure, including the mimicry of the lyrebird. “We have established that each population has a characteristic singing sequence, where individual males sing the same singing sequence many times during the breeding season with only minor variations, and their neighbors sing a very similar singing sequence, but they are not differences between populations,” he said. Backhouse

“Our study provides strong evidence that individuals copy the sequences of close individuals, their neighbors, who themselves copy each other's sequences. This provides the ingredients for a 'phone game', in which changes in sequence structure evolve over the range of the species. This process is similar to how geographical differences arise in human communication,” added the author of the research.

Throughout the range of species, the songs were sung with immediate variety and high acoustic contrast, suggesting that the sequence structure is a means of enhancing the perceptions of the repertoire of male lyrebirds.

“Lyrebirds seem to compose their singing sequences to maximize drama: they order individual mimetic samples so that consecutive samples are as dramatically different as possible. This seems like a great way to give the listener the best and fastest impression of the virtuosity of macho mimicry,” Backhouse said

And he closed: “Previously, lyrebirds and other vocal imitators were seen as' passive 'imitators, as a tape recorder that simply played what they heard. This research shows that lyrebirds, in fact, use their mimicry to 'compose' long and complex songs, all in an effort to attract their female listeners.”

KEEP READING: