Birds Learning to Sing Lose Their Natural Tunes When Impostor Dads Raise Them

Bengalese finches Steve Higgins / Flickr

Is your intelligence or sense of humor genetic or learned? A new study on bird songs might help us understand the complexities of the debate over nature versus nurture.

Researchers at UC San Francisco did experiments with Bengalese finches to determine how they knew what kind of song to sing—whether the tempo of their call was learned, genetic or some combination of both. They collected eggs from nests and separated them into three groups. One group grew up hearing no songs at all, one group heard songs from a computer and one group were exposed to other adult male birds and heard their songs.

The group that heard no songs at all grew up to sound like their biological fathers, implying that they are born knowing the pitch and pace of their calls. Researchers took those eggs from the nest immediately after being laid, so that they could not hear songs even in the egg.

The group that heard songs from a computer did the same thing: they sang the songs of their biological fathers and ignored the "synthetic tutor," as the researchers called the computer program.

But the group of finches who observed adult males singing in real life learned to sing from them. 53 percent of their tempo was from the unrelated birds that they had heard, and 16 percent was from their biological fathers.

"This was really exciting because it showed that the experience provided by a live tutor can actually reduce the contribution of genetics to complex behavior like birdsong," postdoctoral scholar David Mets told "We knew before that live tutors helped birds learn better and faster, but we were surprised to find that this experience can actually override the bird's genetics." Mets was the first author on the paper.

The research, published in the Proceedings of the National Academy of Sciences, can also help inform our understanding of human behavior. While we know that genetics and environment can influence multiple aspects of human behavior, this study shows how inherited traits can be disrupted through training.

"This is far into the future, of course, but it highlights the potential of early behavioral intervention to help mitigate negative genetic traits, such as a predisposition to psychiatric disease," UC San Francisco neuroscientist Michael Brainard told