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Frequencies of Life Forms September 12, 2006

Posted by healthyself in 250- 500 Hz, Animal Research, Blogroll, Cell phone safety, Coherence, Environment, Frequencies, Harmonics, Hz, Music, Sound, Vibration, Waves.

Humans: “Because humans also filter a multi-frequency sound source when vocalizing, the scientists suggest that the birdsong mechanism may be akin to human speech.”
“To produce a sound, a dolphin exhales high-pressure air through its nasal passages to its blowhole. On the way, the air must pass between the monkey lips, like air blown hard between two pieces of grass, or an oboist’s breath between the two reeds of his instrument. The sound echoes off the skull and air sacs and passes through the melon into the water as a tightly focused beam of sound energy.”

Frogs: “The male Leptodactylus ocellatus, which lives in South America, calls at about 250 to 500 Hz (roughly an octave, from middle C to C above middle C). His volume is no match, however, for a neighboring species, which overlaps his frequency range and can croak 40 decibels louder. That’s like the difference between a conversational tone and the noise on a factory floor. L. ocellatus, however, has evolved a way to circumvent this potential problem—by croaking underwater. Because sound travels well underwater, but doesn’t cross the interface into the air, L. ocellatus avoids sonic competition without changing his preferred octave. In a rich environment, species divide the environment up into tinier and tinier slices, each becoming a specialist.”

Fish hear—or feel—sound in two ways. Some have small bones connecting the inner ear to the swim bladder, creating in effect a single large ear. Fish have no outer ears, and therefore no need for the middle ear bones that connect the eardrum to the inner ear. But they do possess an inner ear similar to those of other vertebrates.”

“But fish also detect vibrations in the water with a unique lateral line system similar in many ways to our inner ears. Where organ of hearing in our inner ears forms a coil, that of fish lies stretched out along its side. The lateral line tube stretches the length of a fish, and sometimes branches around its head. The tube connects to the water by way of small pores in the skin and scales. Mucus fills the tube, just as in our cochlea. When a pressure wave strikes the fish, it jiggles the mucus and bends small hairs that project into the mucus in bunches. The hairs trigger nerve impulses, which travel to the brain. While fish cannot determine the location of a sound detected through the single swim bladder, they can locate sounds detected by way of the lateral line.”

Dog can hear sound as high as 40,000 Hz.

Grasshopper can hear up to 50,000 Hz.

Mice: Can hear frequencies between 1,000 and 100,000 Hz.

Moth Noctuid: Moth has a hearing range between 1,000 and 240,000 Hz.

Pigeon: can detect sounds as low as 0.1 Hz.

Rat: has hearing range between 1,000 and 90,000 Hz.

Elephant: has hearing range between 1 and 20,000 Hz. The very low frequency sounds are in the “infrasound” range. Humans cannot hear sounds in the infrasound range.

Dolphin: can hear frequencies up to at least 100,000 Hz.




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