Every air-breathing vertebrate possesses a larynx which is similar to a structure of muscles and folds that protects the trachea and in many animals, vibrates and modulates to produce a stunning array of sounds.
As for the birds, while they have larynges, they sing through the use of the different organ. It is low in the airway, down the place the trachea branches to head off towards the two lungs. It is referred to as syrink, and it is a uniquely avian feature. Scientists have, for decades, been asking the reason the syrinx exists and how it came to be in the first place.
A group discovers that the syrinx confers an advantage by sitting so low in the airway, the syrinx tends to produce sound with high efficiency. This same group is the one that brings about biology, physics, engineering, and computation and they published their results in PLOS Biology.
Ingo Titze, a co-author of the study and the director of the National Center for Voice and Speech at the University of Utah, said that he is always excited when something is counter-intuitive.
For more than two decades, Franz Goller of U biologist studied the mechanics of the syrinx. His findings led him to see similarities between the design and control of the syrinx with the mammalian larynx. The question remained why birds have evolved a syrinx even when they also have a larynx.
Next is the need to understand the evolution and to identify the trade-offs between two different structures with the same function. How come the low syrinx is the best place for a bird's vocal organs and how would it be possible to test that in a bird? As for Riede, it cannot be possible since no one can move the vocal source up and down the tract.
Researchers joined forces and brought a different aspect of acoustical simulation to the study, combining their discipline and methods. They follow a three-pronged approach to measure the different effects of syrinx position over vocal efficiency: computational simulation, simplified physical models, and real birds of varying body sizes in the laboratory.
Riede claimed they found that sound is produced with greater efficiency by a sound source in syrinx position. According to the result, it supports a hypothesis that birds with a syrinx in the airway are better able to communicate and gain an evolutionary advantage.
It is feasible for birds with the longest necks of all terrestrial vertebrates to use the long necks as resonators to amplify the sound.
Other factors the researchers used was to look at the diversity of birds and see how their result applies to birds of different sizes across the range from ostriches to hummingbirds and identify other factors that add to the evolution of syrinx in a particular species.
