The Galapagos Marine Iguana is mute, it recognizes and utilizes the alarm call of the Galapagos Mockingbird. This is the first instance of a non-vocal species eavesdropping on another species’ calls. Both the iguana and mockingbird fall prey to the Galapagos hawk, so by recognizing the mockingbird’s warning the iguanas gain important information on avoiding predation. (more)
Being sensitive to clues in your environment can save you, too.
If you feel a funny vibration when you step on your car's brakes, trust your instincts. Inspect. Car vibrations never get better by themselves. They only get worse.
If you have the funny feeling you are being eavesdropped upon, trust your instincts. Inspect. The thought would not have occurred to you if everything were fine.
(Your inspection station.)
