Elephant calls can be heard up to a distance of 10 km. Now, researchers have discovered for the first time how big the animal is able to produce a sound like that.
It turns out the same way with how people talk, push the water from their vocal chords to vibrate. Even so, the elephant can achieve a lower tone of voice Pitara humans because they are eight times longer.
“The sound produced it was like a piano keyboard,” said study researcher Christian Herbst, voice scientist at the University of Vienna, Austria. In fact, with a frequency of less than 20 hertz, the main components in this call will not be heard by human ears.
Up until now researchers did not know how elephants can produce sound in. In fact it is very difficult to study sound production in animals, said Herbst told LiveScience. In humans, researchers can insert the camera into the throat to the larynx or voice box while someone makes different sounds. Of course it is difficult to insert the camera into the throat of animals.
There are two ways to generate vibrations in the vocal cords. The first is the active muscle contraction. With this method, the activity in your throat muscles will actively contract to vibrate the vocal cords. For example, when a low growl cat.
Another method of producing sound is myoelastic-aerodynamic (Mead). This mode uses the lungs to vibrate the vocal cords. For example when a man speaks or sings.
From the results of Herbst and his colleagues research, they can figure out which method to use an elephant through the larynx of a dead elephant in the Berlin zoo. The researchers inserted the tube into the larynx and enter the warm moist air to simulate breathing. If this method produces vibration that matches the low-frequency calls of elephants living, then the argument is a sound method Mead elephant. If the vibration does not match the sound comes from the method of ‘grunt’.
But the result is in accordance with the method of Mead, the researchers said in the Aug. 3 issue of the journal Science. Although not ruled out the method of ‘growl’, but more reliable method of Mead as the cause of these elephants call.
“The cool thing for me is nature has a system similar to mammals than the very very large – so we now have evidence of a sound system of the largest land mammals – to very very small like a small bat,” said Herbst.
Frequency scale was also quite impressive, from elephants to less than 20 hertz can bats screeched to a frequency of 110 thousand hertz. While the human vocal chords could produce between 50-7000 hertz sound, and sound are normal between 300-3400 hertz.
“It’s amazing what we humans can do with this system,” said Herbst. When compared with the anatomy of animals of different systems, so researchers can understand how sound can be evolved.
“There are variations in the anatomy of the laryngeal, and usually, nature has good reason to answer why the variations exist.”