In 2009, Monterey Bay scientists used live underwater footage to expose a surprising secret of a deep-sea fish. 13 years later, their ROVs had logged 5,600 dives, helping reveal why the ocean's strangest creatures can look radically different after collection

In the darkness of the deep Pacific, life can look almost impossible. Some animals produce their own light, others have transparent bodies or unusual sensory systems, while some are so gelatinous that they are mostly water. In 2009, Monterey Bay scientists used live underwater footage to reveal a surprising secret about the barreleye fish. Years later, their remotely operated vehicles had logged thousands of dives, helping show why live observations can reveal details that preserved specimens simply cannot, as per a report by Eco Portal.

An estimated one million deep-sea species remain undiscovered, making the deep ocean one of the least explored environments on Earth.