Many scientists who study birdsong are intrigued by the possibility that human speech and music may be rooted in biological processes shared across a variety of animals. Now, new research, published online in Current Biology on November 22, 2017, provides new evidence to support the idea that songbirds and humans have common biological hardwiring that shapes how they produce and perceive sounds.
In a series of experiments, the researchers found that young zebra finches – a species often used to study birdsong – are intrinsically biased to learn to produce particular kinds of sound patterns over others.
Jon Sakata, Associate Professor of Biology at McGill University, is the paper’s senior author. Sakata said in a statement:
In addition, these sound patterns resembled patterns that are frequently observed across human languages and in music.
The idea for the experiments, say the researchers, was inspired by current hypotheses on human language and music. Linguists have long found that the world’s languages share many common features, termed “universals.” These features encompass the syntactic structure of languages (e.g., word order) as well as finer acoustic patterns of speech, such as the timing, pitch, and stress of utterances. Some theorists, including Noam Chomsky, have postulated that these patterns reflect a “universal grammar” built on innate brain mechanisms that promote and bias language learning. Researchers continue to debate the extent of these innate brain mechanisms, in part because of the potential for cultural propagation to account for universals.
At the same time, vast surveys of zebra finch songs have documented a variety of acoustic patterns found universally across populations. Logan James, co-author of the study, said:
Because the nature of these universals bears similarity to those in humans and because songbirds learn their vocalizations much in the same way that humans acquire speech and language, we were motivated to test biological predisposition in vocal learning in songbirds.
Caroline Palmer is a Professor of Psychology at McGill who was not involved in the study. She said:
These findings have important contributions for our understanding of human speech and music. The research, which controls the birds’ learning environment in ways that are not possible with young children, suggests that statistical learning alone – the degree to which one is exposed to specific acoustic patterns – cannot account for song (or speech) preferences. Other principles, such as universal grammars and perceptual organization, are more likely to account for why human infants as well as juvenile birds are predisposed to prefer some auditory patterns.
Bottom line: New research supports the idea that humans and songbirds share common biological hardwiring that shapes how they produce and perceive sounds.