New research published in PLOS Biology establishes a link between woodpecker drumming and brain activity in regions that, in other species, have only ever been associated with vocal learning
, such as birdsong in other bird species and speech in humans. This suggests that woodpeckers learn drumming to communicate with the same neurological wiring by which songbirds learn to sing and humans learn to speak.
Woodpeckers use drumming for numerous activities, such as drilling for food and chipping open cavities in tree trunks to build nests. Communication is also one of its primary uses; woodpeckers drum at certain speeds to negotiate territories or attract mates as well. Until now, however, there was no strong evidence to indicate communicative drumming is learned or instinctual.
Humans and songbirds learn vocal communication with very similar neurological mechanisms. Both have specialized brain regions responsible for developing the micromovements that produce certain sounds and express the parvalbumin (PV) gene, which previously has never been found in the brains of birds that do not learn their vocalizations. However, the new study led by Matthew Fuxjager of Brown University and Eric Schuppe of Wake Forest University has discovered that these same mechanisms are in the corresponding regions of woodpecker brains. “The specialized brain regions coordinate the physiology that controls the movements that allow the birds to peck in certain ways,” notes Fuxjager. Furthermore, open field tests with woodpeckers showed that their drumming activated these regions and expressed the PV gene.
While this new research does not serve as definitive proof that drumming is learned behavior, and not purely instinctual, it does lend credence to the hypothesis.
“We therefore hypothesize that ancient forebrain nuclei for refined motor control may have given rise to not only the song control systems of vocal learning birds, but also the drumming system of woodpeckers,” reads the study abstract. Fuxjager and Schuppe hope that this new finding will help scientists understand how modern brains have evolved.