Hobbies And Interests
Dinoflagellates
Dinoflagellates are the most prevalent bioluminescent organisms in the ocean, with more than 1,800 species. Many of these single-celled organisms release toxins when they aggregate in dense colonies, discoloring the water to produce poisonous red tides. Dinoflagellates typically illuminate when agitated during such events as predator attacks. As they light up, they create a neon blue trail leading to their attackers, signaling local predators to the free meal nearby. Some bodies of water, such as Vieques bay in Puerto Rico, naturally contain huge dinoflagellate populations, which produce a brilliant light show for evening swimmers.
Predatory Fish
Anglerfish live deep within the waters of the Atlantic and Antarctic oceans, and females possess a spinal appendage with a glowing tip that attracts prey to the light. Once the victim is within striking distance, the anglerfish snatches it with her massive jaws. Males don't need this adaptation, as they parasitically attach themselves to females, drawing nutrients from their hosts.
The cookie-cutter shark has a small bioluminescent patch on its underbelly, which its prey mistake for a small fish. The shark is fast and agile enough to dodge the large predators the light attracts, and with its circular mouth and wide lips, it uses suction to attach itself to the larger predator and gouge away a chunk of flesh. Wounds from this shark's attack look as though the flesh were sliced away with a cookie cutter, giving the shark its name.
Prey Fish
The flashlight fish has a photophore beneath each eye, which house bioluminescent bacteria that provide the organ's light. Flashlight fish usually emit bursts of light two or three times each minute, but can dim the light by swiveling their organs back into their sockets. When threatened by predators, flashlight fish dart away in an erratic path, flashing their photophores up to 70 times per minute. The zigzag pattern of flashing lights warns the rest of the school of danger, and often confuses a flashlight fish's attacker long enough for the fish to escape.
Hatchetfish use their bioluminescence for counterillumination, a natural form of camouflage. The photophores on a hatchetfish's underbelly match the intensity of light shining through the ocean's surface, causing the fish to blend into its surroundings and making it virtually invisible to predators below.
Jellyfish
According to the Scripps Institution of Oceanography, about half of jellyfish species are bioluminescent, and almost all deep sea species have photophores. Jellyfish have developed many methods for using bioluminescence defensively, such as releasing glowing particles that make predators think they've swum into a mass of plankton, and marking attackers with a glowing gel that attracts their own predators.
Researchers at Gothenburg University in Sweden are experimenting with green fluorescent protein from bioluminescent jellyfish as a solar battery power source. Zackary Chiragwandi's team successfully used GFP in the creation of a fuel cell that can generate electricity without being exposed to light.