Charles Darwin once posited that birds might flap their wings to transmit , not only to wing. However, this has always been pretty tricky to test. Now, 150 year later, researchers have discovered that crested pigeons use their wing plumages to warn others of impending doom.
Crested birds live in Australia and are known for their interesting haircuts and the interference they make when they fly. From the latter, they have earned the nickname “whistle-winged pigeons”. But whether this sound serves a purpose, or is just a side-effect of flight, has traditionally been unclear.
Now, it turns out that these fowls use a very narrow and specific wing feather- the eighth primary 1 to be exact- to render distinct notes with each downstroke. As the pigeons flap faster, such as when escaping threat, the tempo of these notes increases.
Along with these high notes, the researchers found that the ninth primary wing feathers of the fowls create contrasting low notes. Nonetheless, only the high notes are contributing to sounding an alarm.
“Crested birds signal hazard with noisy wings , not voices, ” produce author Trevor Murray, of The Australian National University, said in a statement. “It shows that fowls really can use their feathers as ‘musical instruments’ to communicate with others.”
The study, published in Current Biology, likewise showed that when other pigeons hear the high tempo flapping sounds, they flee. Meanwhile, when a group of birds heard the wing flapping of a fowl that had had its eighth primary wing feather removed, they just seemed about rather than taking flight.
Being a bird surely has its risks. You have to deal with cats, bird-dogs, bigger birds, and small children running at you. Having an alarm system that is basically an automatic outcome of escaping seems like a pretty good idea.
“The alarm signal is intrinsically dependable because pigeons flap faster to escape predators, and this fast flapping automatically makes the high-tempo alarm signal, ” Murray explained.
What’s more, it’s not just crested birds that are noisy fliers. All sorts of other birds, from hummingbirds and manakins to other types of birds, do not have subtle takeoffs, so health researchers is considered that farther research might unveil more about the evolution and use of wing sounds in this unique group of animals.
“Birds have such prominent voices, we have largely discounted their amazingly complex instrumental audios, ” said Robert Magrath, likewise from the Australian National University.
So, next time you’re in the park and hear the birds making a racket, the music might actually be a little more complex than it first seems.