Miles below, a deep-sea fish approached the camera’s bait then, changing its mind, swam backward to escape. The footage turned out to be a first-of-its-kind sighting — but it wasn’t the last.

Why it's awesome: Earth's oceans are home to many secretive and unusual creatures that humans rarely see — including giant ...

A research expedition in the Tonga Trench filmed a Pacific sleeper shark, a slow-moving, opportunistic predator rarely seen ...