Animals communicate with each other in ways we can't imagine, but there are a few we've figured out. Oh, we can't translate everything yet, but we know how some do it. Environmental Graffiti looks at five animals that have their own languages. For example, some frogs chatter away in a language we can't even hear!
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The frogs’ calls have to compete with other animals’ loud signals. These calls are perceived as very loud to humans. However, there are frogs that communicate only through ultrasound. Their frequency is too high for the human ear to hear. The Huia cavitympanum species that lives in Borneo is the only species known to man that communicates only through high-pitched sounds.
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