Paleontologists have discovered that a three-eyed sea moth predator lived on Earth half a billion years ago with evidence found in one of the most fossil-rich areas of the world. The fossils of Mosura fentoni — a species of arthropod that lived in the Cambrian Period — were discovered in Burgess Shale in the Canadian Rockies, a region known for its exceptional preservation of fossils, according to a paper published Wednesday in Royal Society Open Science.