Tiny coral larvae detect and respond to sound beneath the waves. Many coral species reproduce by releasing their gametes into the water; the gametes then drift to a new spot where they can build new colonies. Because sound can travel over many kilometers within the ocean, many of these coral larvae use sound to detect suitable places to settle, even from far away. Scientists are still working to understand the mechanism by which these larvae detect sound, and how they use sound in conjunction with other factors to decide where to settle.