It was once a popular belief that the ocean was “the silent realm.” This was largely due to the fact that humans are poorly adapted to hearing underwater, and marine animals don’t appear to have “ears” that look anything like the ears of terrestrial animals. We are now finding that the ocean is anything else but silent. In the dark depths of the sea animals have evolved a panoply of adaptations to underwater sound. Some animals use high frequency “bio-sonar” to “see” their surroundings, others use acoustically-generated ‘particle motion’ to sense the proximity of prey and predators; some use long wavelength sounds to navigate over long distances, others chorus with conspecifics like crickets do to keep tabs on their “acoustic communities.”…