The ears on many animals are hidden, under feathers or fur, and sometimes aren't even located in the usual place. If you've inspected every square inch of your chameleon and concluded that he's probably deaf because you can't find evidence of ears, you're not far off the mark. Chameleons have the poorest hearing of all lizards. They aren't completely deaf, but you may wonder if your chameleon can hear you talking.
No Outer Ear...
You can look closely at a chameleon, but you won't see his ears. That's because, unlike many other animals, chameleons don't have outer ear structures. They do have two microscopic holes on each side of their heads close to their eyes, but these tiny ears aren't very useful for hearing. Chameleons rely more on senses other than hearing to evade predators and find food.
...Yet They Can Hear
Chameleons don't hear well, but they can hear some sounds. Softschools.com reports that they can pick up sounds that fall in the frequency range between 200 and 600 Hz. Not too bad for a reptile who doesn't have ears or the traditional hearing equipment that other animals have. Considering that the normal range of the human voice starts at the top end of that scale -- 500 Hz, according to Cardiff School of Computer Science and Informatics -- that means your chameleon can pick up at least some of the words you say.
Pickin' Up Good Vibrations
They may be almost deaf but chameleons have their little tricks for finding food and communicating with each other. In addition to detecting some audible tones, chameleons feel vibrations in the air, sensing the vibration of the beating of an insect's wings, for instance. And in her study "Vibration and Animal Communication: A Review" published by Oxford Journals, Peggy S.M. Hill reports that chameleons create and detect plant-born vibrations that are believed to play a part in communication since they cannot hear well.
Because they don't have a great sense of hearing -- and their sense of smell is quite poor, too -- chameleons have to fall back on their one excellent sense: their eyesight. Chameleons' eyes, located on the sides of their heads, can each move 180 degrees and independently from each other. This gives them a 360-degree view of the world around them. They can even see tiny insects that are as far away as 5 to 10 meters. Chameleons communicate visually, too, letting their skin do the talking for them. Many people think that chameleons change color to blend in with their environment, but their color-changing trick works more like a mood ring. For example, a chameleon who wants to warn another chameleon to back off will turn a bright color such as yellow, red, green or blue, sending the visual message that he's ready for a fight.
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