Have you ever heard of the lowland streaked tenrec? There are several species of tenrec, all found only on the island nation of Madagascar. The lowland streaked tenrec (Hemicentetes semispinosus) is unique in that it is the only known mammal to communicate by stridulation, which is so rare that we need to explain the word stridulation. It is the act of communicating by rubbing body parts together, in the manner of crickets and lobsters. The lowland streaked tenrec has seven to sixteen specialized quills on its back, arranged in three rows, that produce sound when rubbed together.
We can hear the mechanical rubbing of these quills in the video, but the sound other tenrecs hear is a higher frequency than human ears can detect. We can assume that they interpret meaning in these sounds, like a warning of danger, a cry for help, or location communication between mother and child. -via Metafilter
(Upper video source: TheFolkman)