Paleontologists at the University of Hokkaido Museum in Japan, in partnership with the American Museum of Natural History, proposed forming major parts of what they called the “voice box”, which is an embodiment of the sounds of dinosaurs by analyzing their throats that were found in ancient fossils.
Despite the dinosaurs’ relatively distant relationship to birds, the dinosaur’s larynx bears many similarities to the speakers of birds that we know today, according to scientific research published in the journal “Communications BiologyScientific, mid-February.
How does the sound come out?
Scientific research explaining the mechanism of making sounds for dinosaurs. Their larynx is a hollow tube located in the upper part of the throat and contains anatomical features adapted to produce sound waves.
The larynx produces different sounds when the air is exhaled, as its tissues vibrate at specific frequencies, and as a result of the vibration, a sound is produced that differs between animal species, including dinosaurs.
As for birds, the research indicated that they have a “strange exception”, as the bird species have a “syringe” located at the opposite end of the trachea to the larynx.
The syrinx of birds contains two separate “tubes”, which allows them to make two different sounds at the same time, and they also have another structure in the trachea that allows them to modify the sounds they produce more deeply.
For the scientific community, the birds we know today are descended from flying dinosaurs, but because the voice box is made of soft tissue, the researchers were able to find very few ancient examples in the form of fossils to study.
The oldest “bird whistle” ever found is 66 million years old, and is very similar to what ducks and geese have today.
vocal models
Scientific research has said that Pinachosaurus, for example, had an elongated larynx, unlike other reptiles, which indicates that the dinosaur would not have used its larynx as a sound source but as a sound modulator as well, while modern birds modulate sound using a different structure.
The researchers believe that the sounds made by Pinacosaurus were associated with “courtship, parental calling, and self-defense from a predator” and may have included cooing and chirping.
The scientists saw that the large, mobile larynx of Pinachosaurus, characterized by a large annular joint, was linked to the regulation of airflow that modulates the respiratory system, along with vocal communication.
In particular, the vocal features of Pinachosaurus are similar to those of birds, suggesting that the motor larynx of Pinachosaurus is similar to parrots and their parakeets, which could have greatly altered the composition of the laryngeal cavity.
At the same time, the airway protection mechanism cannot explain the larynx shapes found by scientists, since this mechanism does not require a large, mobile larynx to close the “glottis.”
As a result of the research, the researchers theorize that the larynx of Pinachosaurus was specialized for opening the glottis and possibly modulating the sound with other vocal tracts such as the trachea, oral cavity, esophagus, and pharynx.
