- Some species of birds are known to learn vocalizations, while others are not
- Birds learning vocals activate specific areas of the brain when learning their song
- One study found that woodpeckers use these same areas when drumming
- This suggests that it is a learned ability and developed in the same way as vocal learning.
A new study has found that woodpeckers are using the same part of the brain as birds to learn to sing while carrying their beaks into trees.
The forelimbs of the bird have specialized beak areas that are associated with birds and the human language systems.
These have previously only been found in bird species that learn and produce vocalizations, which the woodpecker does not.
However, researchers from Brown University in the United States found that these same areas are activated by the bird’s distinctive tree drumming.
The discovery suggests that its ability to peck rhythmically evolved in the same way as vocal learning in animals and language in humans.
The lowly woodpecker’s forelimbs have specialized beak regions that are associated with birds and human language systems (stock image).
Brain diagrams showing the drum control nucleus and their connections in woodpeckers compared to similar nuclei and connections in birds with vocal learning. A: Song Learning Nuclear are RA, HEVC, LMAN and Area X. B: Controlling the drum are the nuclear archopallium (DA), anterior nidopallium (DAN), and dorsal lateral nidopallium (DLN). C: No nucleus for song learning and woodpecker drumming is present in the brain of bird species that have not learned to sing.
How was the study done?
Scientists knew that some birds learn to make sounds by imitating older birds, while others are born with the ability.
To examine differences in brain activity between learners and non-learners, they visualized the brains of species in the latter group, which also includes the downy woodpecker.
To their surprise, the woodpeckers showed activity in areas of the brain that birds use to learn song.
After playing the woodpecker to the sound of some drumming, the researchers found that it activated these brain regions.
This suggests that birds may learn the drumming patterns of their beaks rather than vocalizations.
The brain regions they use when pecking may also have evolved in the same way as those used by other species for vocal learning.
Lead author Professor Matthew Fuxjger said: ‘Woodpeckers have a set of specialized brain regions that control their ability to drum, or rapidly hammer their bills on trees and gutters during fights with other birds.
‘Moreover, these brain regions appear remarkably similar to the parts of the brain in songbirds that help these animals learn to sing.’
Woodpeckers use their long tongues to burrow into the bark of trees to build nests and carve cavities to hold food.
They sit vertically on trees and repeatedly slam their beaks into the trunks, as if playing a drum or drilling.
Birds also use noise to defend their territories and scare off potential intruders, in the same way that birds do.
The production of both drumming and birdsong also requires rapid and complex motor movements, and must be adaptable when birds compete with each other.
These factors suggest that they may have neurological similarities, and songbirds are known to express a marker gene called parvalbumin (PV) that regulates vocalization learning.
PV is also associated with language learning in humans, which is similar to bird song in that it is learned at a young age and requires complex muscle coordination.
However, the gene has never been found in the forebrains of birds that do not learn their vocalizations.
Microscope images of PV-rich forebrain nuclei in song-learning hummingbird (green box) and drumming woodpecker (red box). The white dashed regions indicate the boundaries for the song control regions. The blue dashed regions indicate particular PV regions. Scale bar = 2 mm
Some birds, such as hawks, are born with an innate ability to speak, while others, such as songbirds and parrots, must listen and imitate older birds to learn this.
for this study, published yesterday PLOS BiologyThe scientists were checking to see if the brains of birds that didn’t learn their calls looked different from those of them.
Earlier research has suggested that PV activity is promoted in birds that learn their vocalizations, so they wanted to confirm that this was not the case in some non-learning species.
This included flamingos, ducks, hawks, penguins and lowly woodpeckers, but, to their surprise, they found that the latter had specialized brain regions that make up PV.
These regions are similar in number and location to many forebrain regions that control song learning and song production.
Woodpecker drumming, like birdsong, may have been a learned behavior, and has evolved in the same way as vocal learning in animals and language in humans (stock image)
To test how the lowly woodpecker used that part of its brain, the researchers played drumming sounds through speakers near their nesting cavities in the wild.
They then examined the forebrains of woodpeckers that played drums in response to sound, and found that it triggered activity in PV brain regions.
This suggests that drumming, like the song of birds, may be a learned behavior, and has evolved in the same way as vocal learning in animals and language in humans.
These findings enhance the understanding of how brain systems evolve to perform new, but similar functions.
Woodpecker heads ‘act like hard hammers’, not safety helmets, study finds
Scientists have debunked a popular theory about how the woodpecker could repeatedly bang its beak against a tree at high speed without causing brain damage.
The researchers analyzed high-speed videos of three species of woodpeckers – the stacked woodpecker, the black woodpecker and the great-spotted woodpecker.
He found that his skull didn’t work…
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