How songbirds produce their beautiful melodies: Avians can control INDIVIDUAL vocal muscle fibers, which gives them incredibly fine control over their melodies
- Songbirds can control individual vocal muscle fibers, researchers in Denmark found in
- This ability gives you incredibly fine control over your melodic melodies
- Important because it is the females who decide whether they are attracted to a male
- But just like humans, songbirds have to learn their song from a teacher through imitation
Their beautiful melodies make for the perfect early morning wake-up call, but how do songbirds do it?
It turns out that their secret is to control individual vocal muscle fibers, as researchers in Denmark have found, which gives them incredibly fine control over their melodies.
Such control is important because females recognize these small changes and use them to decide whether or not they will be attracted to a male.
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Melodies: Songbirds like the zebra finch (pictured) can control individual vocal muscle fibers, researchers in Denmark have found, which gives them incredibly fine control over their melodies
TOP 10 MOST FOUND SONGBIRDS IN THE UK
Blue tits are often seen in British gardens
- House sparrow
- Blue tit
- Wooden pigeon
- Great tit
- Long-tailed tit
Songbirds make their sounds with a special vocal organ known only to birds, the syrinx. It’s surrounded by muscles that contract at super-fast speeds about 100 times faster than the human leg muscles.
“We found that songbirds have incredibly fine control over their song, including frequency control below one hertz,” said Iris Adam, lead author of the study and assistant professor at the University of Southern Denmark.
A motor unit is the muscle’s basic unit of contraction and is made up of a motor neuron and the number of muscle fibers it is connected to and which it activates.
By combining tissue preparations for counting muscle and nerve fibers and mathematical models, the researchers were able to show that a large part of the motor units must be very small and even as small as a single muscle fiber.
“Motor units vary in size from hundreds or thousands of muscle fibers in our leg muscles to as little as 5-10 in the muscles that control eye position and the muscles in the larynx,” said Dr. Coen Elemans, lead author of the study and lead study of the Sound Communication and Behavior Group at the University of Southern Denmark.
“In the vocal muscles of zebra finches, our models predicted that 13-17 percent of motor neurons innervate a single muscle fiber.”
Songbirds produce their sounds with a vocal organ called the syrinx, which is unique to birds (see illustration).
To understand the effect of such small motor units on singing, researchers also measured how much stress the muscles can exert and how that stress changes the frequency of the sound.
“We found that songbirds’ vocal muscles had the lowest stress levels measured in any vertebrate animal,” added Adam.
“They are some of the fastest muscles known, and now we’re showing they are also the weakest with the greatest possible degree of control.”
Songbirds evolved about 40 million years ago and quickly evolved into the group of birds we know today. Singing is critical for females to find and judge males and can even fuel the creation of new and different species.
However, just like humans, songbirds have to learn their song from a tutor through imitation, researchers found.
“We believe that in addition to having a special syrinx and its amazing ability to mimic sounds, the subtle gradation of song features like pitch has increased the number of different sounds a bird can make,” Adam said.
In April this year, the RSPB warned that nearly 80 percent of Britain’s most popular songbirds are in decline.
The world’s largest wildlife study, Big Garden Birdwatch, found that 16 of the 20 most commonly sighted garden birds were down year-over-year.
More species are currently facing declines than they did in 2020, when half of the birds in the top 20 saw declining numbers, the conservation group said.
Over a million nature lovers counted 17 million birds in their garden in one hour on the last weekend in January – twice as many people who took part in the charity’s giant birdwatching the previous year.
The study found that the house sparrow remained number one, but 16 of the top 20 bird species showed a decrease in average numbers compared to last year.
Thrushes have declined a staggering 78 percent over the past four decades, despite a slight increase this year.
Only robins, blackbirds, carrion crows and the song thrush increased in 2020, with habitat and food loss being the reason most bird species have declined in numbers since bird watching began 42 years ago.
BIRDS USE SONG TO COMMUNICATE WITH OTHER BIRDS
Birds use their voices to communicate with other birds.
Sharp melodies are an efficient way to communicate over long distances, especially if you are small and live in dense habitats like rainforests.
Most species of birds use specific calls to identify themselves and communicate a nearby threat.
Bird song is a special type of call that is used by many species to help them mate.
Chirping birds is almost entirely a male activity and helps the singer indicate that he is fit, healthy, and ready to procreate.