Fireflies are not the only light-emitting creatures. There are a number of species that demonstrate the phenomenon of bioluminescence – the ability of living things to emit light.
These bioluminescent creatures range from flying animals to deep water ones. Their mechanism of emitting light and the reason often differs from one another. Considering how greatly interesting these creatures are, we decided to share the 10 most fascinating bioluminescent species that scientists know of. Read about them below.
1. Dismalites
There are worms that glow called dismalites that can be found in very select places in North America. The larvae of these worms live in stream banks and sandstone caves. Dismalites (Orfelia fultoni) use their blue-green light to find food by attracting insects. Once the insects take notice of the light, they fly into a sticky web spun by the worms and are eaten, which may make the worms something other than dismal. These small worms can be found in North Carolina, Tennessee, and Virginia, and were named after the Dismal Canyons in Alabama.
2. Anglerfish
Anglerfish may not look like the friendliest denizen of the seas, but the fish uses bioluminescence to its advantage much like the prettier creatures. There are a wide variety of anglerfish and they can be found in both open water and benthic environments. They also take a multitude of forms, including round and long. All of the species are not very big (the largest grow to 250 mm). They do have a big mouth that snaps upon their prey which swims toward the light that sprouts from a long filament which sprouts from the middle of their forehead. Unlike previous creatures, which emit light by being disturbed, the light that spells the end of many tiny swimmers’ lives is produced by a symbiotic relationship with bacteria. One species of anglerfish that you may have heard of, and even consumed, is the goosefish.
3. Bioluminescent Jellyfish
A jellyfish that flows and glows is one of the most beautiful sights that nature provides. The species Aequorea victoria (also known as crystal jelly) produces a series of blue light flashes by releasing calcium, which reacts with the photoprotein aequorin. While crystal jelly emits blue and green light, jellyfish throughout the seas emit a rainbow of colors. A newly discovered jellyfish emits a red glow. Jellyfish become luminescent when they are touched (as well as providing that sting) as a warning to their fellow creatures.
4. Firefly Squid
The firefly squid, also known as the sparkling enope squid, has organs called photophores at the end of each tentacle which emit light. This light is used as a siren song for little fish, which the three-inch squid subsequently munches upon. The squid, which generally live 600-1200 feet below the ocean’s surface, is the only cephalopod to develop color vision which may allow them to differentiate between bioluminescent and ambient light. If you’d like to see the firefly squid for yourself, you can take a sightseeing boat from the Japanese port of Namerikawa. Be forewarned, however, the boat leaves at 3AM.
5. Dinoflagellates
Dinoflagellates are marine plankton. these microorganisms glow with bioluminescence when disturbed. Perhaps the most well known example of this light can be found in Mosquito Bay, which is off the coast of the Puerto Rican island of Vieques. The bay, also known as The Bio Bay, has the perfect combination of elements for the dinoflagellates to show off their blue glow.
6. Glowworms
Like dismalites, glowworms use their bioluminescence to attract insects into a web. For this reason, their Latin name is Arachnocampa (which translates indirectly to spider-worm). Perhaps the most well-known glowworm is the Arachnocampa luminoso of New Zealand. In addition to using its light to attract unsuspecting prey, the New Zealand glowworm uses the light to burn off energy. The light is made via a chemical reaction between chemicals emitted by the glowworm and the oxygen in the air. In New Zealand, glowworms survive in caves because they can spin their webs from the cave ceiling. The dark caves are also conducive to the bioluminescent light being seen more easily. Other species of glowworms can be found in dark places in Wales, Tasmania, and Australia.
7. Foxfire
Foxfire are a type of mushroom that exhibit bioluminscence. These mushrooms which are part of the genus Mycena provide a slight green glow at night. Of the 500 species of mushroom that are filed under Mycena, only 33 are known to be bioluminescent. Foxfires have had practical applications as people from various parts of the world have used the mushrooms as a natural lantern.
8. Vibrio Harveyi Bacteria
Vibrio harveyi floats in the ocean and are mainly thought to reside near the tropics. They are the likely cause of the effect known as the milky sea, the world’s largest bioluminescent area, which is roughly the size of Connecticut. This effect was largely thought as a myth (even mentioned by Jules Verne in 20,000 Leagues Under the Sea) until being verified by scientists in 2005. Perhaps the most unusual aspect of V. Harveyi is that they seem to communicate with each other via a process called quorum-sensing. This process of cell-to-cell communication which regulates gene expression based on population density is produced by the release of an auto inducer. In addition to luminescence, the auto inducer release regulates production of antibiotic and biofilm.
9. Fireflies
Fireflies are perhaps the most famous bioluminescent creature. There are over 2000 species of firefly (which are also known as lightening bugs). For example, Photinus pyralis produces light via a chemical reaction between a pigment called luciferin and oxygen. Carbon dioxide is the most common chemical which is released by this reaction. Luciferin has a number of applications for people, including for use in blood banks to examine whether red blood cells are breaking down. Fireflies can regulate the amount of oxygen that enters their abdomen (where the chemical reaction takes place), which can create a flashing pattern. In case you were curious, fireflies hibernate during the winter in larvae stage. In Malaysia, fireflies have been known to flash in unison. While fireflies regulate their lights individually, they receive feedback from other light flashes around them.
10. Animals Glowing Because of Scientific Experiments
Researchers have introduced substances such as green fluorescent protein to animals including rhesus monkeys and pigs to examine a wide variety of ailments. For example, in 2008 scientists infected unfertilized rhesus monkey eggs to study Huntington’s disease. The study examined the disease’s effect on monkey brains. Green fluorescent protein was introduced to pigs by researchers in Taiwan to study the development of adult stem cells. Fluorescent proteins have also been introduced to animals to study cloning. Red fluorescent protein was introduced to cloned cats in 2007 via DNA by scientists in South Korea. The function of mice brains have also been studied at Harvard by introducing cyan, red, and yellow fluorescent protein. Individual neurons were given different colors to study how neurons work together in a distributed fashion.
