Sunday January 10, 2021, 00:43
Animals use the sound to communicate with the aim of defending territory, looking for a partner, warning danger or simply for social interaction. That is why Ethology distinguishes sound and calls (‘sound’ and ‘call’). Evolution has endowed every animal species with a frequency range, the fundamental and its harmonics. A question arises: is there a rule that arranges this frequency selection? Let’s see more about how sound occurs in the animal kingdom.
Most terrestrial vertebrates have small tissue folds, vibration valve, which produce vibrations and sound when the air is turned off. However, the sound in the birds is found in the folds of a small cartilage box, located where the windpipe to the lungs branches. It is called Siringe. Perhaps in this case the evolution was looking for an organ with more differentiating capacity than the larynx. This allows the 10,000 bird species to each have their own frequencies. The specific frequencies of the sound (fundamental and harmoniously) produced in the larynx or the syringe are pillows or improved, selectively, when passing by the Supralaring vocal system, which has natural resonating properties. Passeriform birds and some frogs are an exception. They only use the fundamental frequency. The sound is irradiated by the mouth or peak. Insects, without a respiratory system that generates pressure air, produce sound on mechanical means. They usually use a membrane, a muscle that produces the collapse of a membrane that covers a resonating body cavity, etc. The frequency range has very little or no fine structure. Moreover, we have animals that use echolocation and aquatic animals.
Experimental studies have shown that small animals use higher than large frequencies. Moreover, large mammals and birds communicate more than the little ones. It has been deduced from these experimental records that there is a connection between the dominant frequency of the broadcast sound and the size of the animal it broadcasts. This has led to the formulation of a rule that says that the dominant frequency of each species is inversely proportional to its longitudinal size. Formulated on the basis of the dough, he says that it is inversely proportional to its cubic root. This proportionality formula corresponds to the increase in Mondemissie Efficiency by increasing the frequency. Rule that saturation reaches when the wavelength of the sound is comparable to the diameter of the mouth. With the help of the physical principles that explain the noise production together with anatomical variety, lifestyle and habitat, it has been shown that, with small changes, there is any species around the rule.
