Scientists have learned that young male songbirds who babble trying to learn their song perform better in the presence of a female bird. University of California - San Francisco
scientists say when a female songbird comes around, teenage males working hard toward perfection become better vocalists, sounding almost like mature adults.
The findings, published in the Proceedings of the National Academy of Sciences
, have implications for understanding social cue and learning in humans that might be applied to rehabilitation of people with motor skill disability and brain injury.
Bird watchers and scientists have thought young birds could only produce immature sounds, just like human babies. Researchers studied the male zebra finch song, using recordings, to find young male finches sang better when a female was around.
"We were very surprised by the finding," said senior author Allison Doupe, MD, PhD, a professor of psychiatry and physiology and a member of the Keck Center for Integrative Neuroscience at UCSF. "The birds picked the best version of the song that they could possibly perform and they sang it over and over again. They sounded almost like adults. It turns out that teenagers know more than they're telling us."
Doupe says there is much to be learned from the social cues seen in the male songbird, the brain, learned behaviors and how language is acquired that also could apply to humans.
"We know that variation by trial and error is an important part of the learning process," said Doupe. "But discovering precisely how social cues influence motor production during song learning in birds could shed light on the brain mechanisms that underlie similar processes in humans learning how to speak, and potentially allow scientists and clinicians to harness these mechanisms when learning is not progressing properly."
Researchers explain adult zebra finches sing two different types of tunes. Their songs are at times undirected and at other times more precise and favored by females.
For the study, scientists coaxed the young songbirds to sing to females as they would during courtship, then used computer software to analyze their sounds. The undirected tweeting was variable, but when directed, became more like an adult song.
Doupe says when songbirds learn they first need developed motor neurons to mimic what they're hearing, generated in the basal ganglia of the brain. It's through experimentation that they learn.
He adds it's social cues that improve learning, found in the study. The young male birds performed better when females were around, showing how learning develops. The study highlights the importance of songbirds for teaching scientists the underpinnings of language and motor skill development that could be applied to helping humans.
PNAS: doi: 10.1073/pnas.101050210