Q: Is the noise that dolphins produce, is is art(ie.music) or a way for them to comminicate?
A. Dolphins (along with whales) certainly do make a variety of sounds underwater. These sounds are used primarily to communicate, and also may be used as a kind of "sonar" to detect objects underwater. See the question on Whale Communication on this page for more information.
About dolphins and music: It has never been shown that dolphins make noises strictly for their own pleasure. Of course, human artists have incorporated whale and dolphin sounds into their own musical work.
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