US researchers led by Matthew Foxger of Brown University and Eric Schube of Wake Forest University have found regions of the woodpecker brain that so far have only shown features associated with vocal learning in animals and language in humans.
The study, published last Tuesday in the journal Plus Biology, showed that these areas, which appear active in humans and birds when they speak or sing, are also active in woodpeckers during pecking.
The scientists studied songbirds because there are many similarities between human language and bird song. Both are learned in childhood, require complex muscle coordination and are controlled by specialized areas in the brain.
In both humans and songbirds, these areas contain a specific gene called parvalumene. This gene is not found in separate nuclei in the forebrain of songbirds, which cannot learn to speak.
However, when PV gene expression was investigated in several previously unstudied bird species, including flamingos, ducks, penguins and woodpeckers, surprisingly, the researchers realized that woodpeckers have special regions of the brain that make parvalumene. They also discovered that these regions are similar in number and location to many of the forebrain nuclei that control speech in humans and songbird song learning and production.
In tests with woodpeckers, they found that the birds’ behavior that triggers brain activity in these regions is actually clicking with their beaks.
Like birds’ vocalizations, woodpeckers use clicking to defend their territory when competing with each other, and while scientists have yet to prove that clicking is a learned behavior, the new evidence discovered about their brains suggests it is.
In a report on Brown University’s website published alongside the publication of the study, Dr. Matthew Foxger said: “Finding this non-vocal communication system that is neural and functionally similar to songbird songs and human speech could help us understand how brain systems evolve.”
