[[quoteright:342:[[Film/{{Avatar}} http://static.tvtropes.org/pmwiki/pub/images/Bioluminescence_3731.jpg]]]]
[[caption-width-right:342:Pretty, isn't it?]]

A ScienceFiction trope: when writers think up alien lifeforms, there are several ways to make them cool, but nothing beats making them ''glow''.

TruthInTelevision, as many deep sea species have bioluminescence, including [[EverythingsSquishierWithCephalopods many octopuses]].

{{Supertrope}} to GlowingFlora. See also PowerGlows, FantasticLightSource and AlluringAnglerfish. Compare TronLines and GlowingGem. Contrast SicklyGreenGlow.



[[folder:Anime & Manga]]
* ''Anime/GargantiaOnTheVerdurousPlanet'' gave us the whale-squids, although it is a bit uncertain if they actually are bioluminescent or merely fluorescent-when-lighted a la GFP below.

[[folder:Films -- Animation]]
* In ''WesternAnimation/{{Bionicle}}: The Mask of Light'', [[KidAppealCharacter Takua]] gets distracted by some glowing coral-like structures. He immediately puts them on his head and starts hopping around like a fluorescent bunny rabbit.
* ''WesternAnimation/FindingNemo'' has an AlluringAnglerfish which in addition to being a terrifying predator looks ''very'' cool. The sequel ''WesternAnimation/FindingDory'' includes a bioluminescent squid in a similar vein.
* The glowing fireflies in ''Anime/GraveOfTheFireflies''.
* In ''WesternAnimation/HowToTrainYourDragon2'', it is revealed that the dorsal area on the backs of [[spoiler:Night Furies]] can light up in streaks of blue, possibly in a ShoutOut to ''Franchise/{{Godzilla}}''.
* In ''Disney/{{Moana}}'', both [[GiantEnemyCrab Tamatoa]] and the green algae in his lair.

[[folder:Films -- Live-Action]]
* ''Film/{{Avatar}}'': Most lifeforms on Pandora, including much of the vegetation, have bioluminescent cells. The Na'vi have them as markings that form lines, which according to the background serve as a means of identification. Most plants, along with small animals, have a '''lot''' of bioluminescence, with larger animals and trees having less, although everything seems to have at least some.
%%* The aliens from ''Film/TheAbyss''.
* [[JustifiedTrope Justified]] in ''Film/PitchBlack'' due to the BizarreAlienBiology of the light-sensitive monsters that eat everything else on the planet [[FridgeLogic during every eclipse]]. [[spoiler:The glow-worms end up saving the lives of the survivors.]]
%% * The aliens from ''Film/{{Monsters|2010}}''.
%%* The Moorwens from ''Film/{{Outlander}}''.
* UpToEleven in the movie of ''Literature/LifeOfPi''. Apparently ''every'' body of water glows piercing blue at night. Justified as bioluminescent plankton and pelagic worms really are very common on the tropical Pacific.
* The aliens in ''Film/AttackTheBlock'' have neon turquoise ''teeth''. And a fur so dark it always appears pitch black, thus the teeth are the only visible trait.
* The {{Kaiju}} from ''Film/PacificRim'' have glowing blood, alongside their glowing [[ThroatLight mouths]], [[GlowingEyesOfDoom eyes]], and [[VolcanicVeins markings.]]
* ''Franchise/{{Godzilla}}'':
** The Big G's dorsal plates traditionally light up before or as he uses his [[BreathWeapon Atomic Breath]].
** The [=MUTO=]s from ''Film/{{Godzilla 2014}}'' are black with glowing red markings. Godzilla's dorsal plates begin to light up blue, just like they do in the TOHO films. The new film adds in the plates glowing blue from the tail up, à la WesternAnimation/GodzillaTheSeries.
* Electro in ''Film/TheAmazingSpiderMan2'', whose body glows a continuous blue.
* In ''Film/GuardiansOfTheGalaxy'', when the team explores a dark chamber to retrieve the Orb from Ronan, Groot expels a cloud of bioluminescent seeds to light the darkness.
* [[EverythingsSquishierWithCephalopods Creech]] from ''Film/MonsterTrucks'' displays this ability whenever he is seen swimming in water. [[spoiler: His parents and the other members of his species]] display this ability as well.

* In ''Literature/{{Kraken}}'', the Krakenists believe that after they die, they become bioluminescent cells on the body of the squid god.
* In "Literature/DarkLife" by Kat Falls people who live on the bottom of the ocean for extended periods of time often develop a bioluminescent shine from eating certain species of fish.
* Creator/WayneBarlowe seems to like this trope, given that he was a creature designer for ''Film/{{Avatar}}'' and he wrote and illustrated ''Literature/{{Expedition}}'', the book that ''Film/AlienPlanet'' was based on.
* The Tendu of Amy Thomson's ''Literature/TheColorOfDistance'' and ''Through Alien Eyes'' communicate through changing patterns on their skins. In the dark, their words glow.
* When Liu steps into Rudak's dome in ''Literature/JunctionPoint'', every surface is covered in plant-like life that glows in greens and blues. Whether it's just natural, or the result of bioengineering, has yet to be determined.
* In ''Literature/DeceptionPoint'', the first clue that the meteorite find is fake is that the hole it's in, supposedly sealed for long ages, turns out to contain glowing (and hence fresh) organisms.
* "What Is This Thing Called Love?" by Creator/IsaacAsimov has a pair of aliens, who communicate using light, having difficulty understanding human biology including speech (which one of them describes as "a sort of complicated coughing").
* In ''Discworld/{{Thud}}'', a mine run by super-conservative "deep down" dwarfs is primarily lit by vurms, bio-luminescent creatures that feed on carrion.

[[folder:Live-Action TV]]
* Darwin IV: Several of the alien species from ''Film/AlienPlanet'' (adapted from ''Literature/{{Expedition}}'').
* During a brief period of unemployment, Sheldon from ''Series/TheBigBangTheory'' mentions trying to engineer some bioluminescent goldfish (specifically to serve as an energy efficient pet/nightlight). It doesn't really come up again after a throw-away gag at the end of the episode, but he was successful in creating at least one.
* One of the challenges on ''Series/FaceOff'' required contestants to design creatures to be displayed under black light as well as visible, meaning the artists had to paint with colors they couldn't even see.
%%* ''Series/TheFutureIsWild''
* ''Series/TheMostExtreme'' had the episode "Night Lights", which was all about finding the most extreme bioluminscent creature. [[spoiler: The female [[AlluringAnglerfish angler fish]] won]]
* In the ''Series/{{Tracker}}'' pilot, Mel catches a glimpse of Cole glowing, something connected to his Cirronian nature and whatever he was doing in the bedroom at the time. (not *that*!)

[[folder:Tabletop Games]]
* ''TabletopGame/DungeonsAndDragons'': Usually in any dungeon crawl situation, there are caves that have bioluminescent moss or lichen growing on the walls/floors.
* In ''TabletopGame/{{Crimestrikers}}'', Nyx Marama is an anthropomorphic bat who can make her body (or part of it) glow in the dark for up to an hour at a time. She's also learned to use this power to create an attack called the Thunderflash, "a momentary blinding glow accompanied by an intense ultra-sonic noise, that can startle, stun and confuse an enemy."

[[folder:Video Games]]
* In ''VideoGame/DonkeyKongCountryTropicalFreeze'', all marine lifeforms are luminescent.
* The hanar race from ''Franchise/MassEffect''. They communicate via patterns of bioluminescence.
* As do the Underlost from ''VideoGame/SepterraCore''. That said, most of Shell 7 is covered with bioluminescent plants/fungi, serving as the primary source of light IN that layer.
* The Macalania Woods in ''VideoGame/FinalFantasyX''.
* The markings on the Demi-fiend in ''VideoGame/ShinMegamiTenseiIIINocturne'' which TurnsRed when he's low on health.
* Definitely noticeable in ''VideoGame/StarFoxAdventures'', which is arguably similar to ''Film/{{Avatar}}'' in its visuals.
* The Slylandro in ''VideoGame/StarControlII''.
* [[FungusHumongous Zangarmarsh]] and [[UnderTheSea Vashj'ir]] in ''VideoGame/WorldOfWarcraft''
* [[TheLostWoods The Forest]], and the creatures who live there in ''VideoGame/{{CreaVures}}''. Interestingly, the bioluminescence on the eponymous [=CreaVures=] also serves as a [[ShowsDamage representation of your health]] (with it fading for a while if you're hit), and sometimes as an indication as to whether an aggressive animal is cowering or not (with ''theirs'' fading for a bit).
* Everything in ''VideoGame/AliceMadnessReturns''' the Deluded Depths. Even Alice's dress has an angler and glowing dots and stripes.
* Glowing Fungus in ''VideoGame/FalloutNewVegas'' in multiple colours. Some are edible.
* ''VideoGame/{{Subnautica}}'': '''EVERYTHING''' on [[SingleBiomePlanet underwater planet 4546B]] glows. The fish glow, the plants glow, the coral glows, the seaweed glows, the giant translucent jelly mushrooms in that one cave glow. Which is extremely helpful, because it is really difficult to see where you are going at night without a flashlight.
* ''VideoGame/{{Terraria}}'':
** In mushroom biomes, the grass and various mushrooms glow almost as brightly as torches. Surface-level mushroom biomes are [[AlwaysNight dark even during the day]] so they too glow.
** Additionally, every kind of herb will glow when blooming, though some more so than others.
* ''Franchise/TheElderScrolls'':
** In different instances in the series, some Spriggan (a hostile [[WhenTreesAttack tree-like]] PlantPeople race) variants give off bioluminescencent green, purple, or orange lights.
** In ''[[VideoGame/TheElderScrollsVSkyrim Skyrim]]'', [[spoiler:Blackreach]] is a huge underground area full of enemies, ruins, giant glowing mushrooms and ''crimson nirnroots'' (which are like regular nirnroots, but are red instead of green). Especially the Dawnguard add-on is fond of this. Both the fauna and flora of forgotten Valley of ancient Falmer love this trope. Caverns are lit by glowing flowers that retract themselves to their shells and animals have glowing blue stripes on them. Similarities with Avatar definitely coincidental.
* ''VideoGame/TheLegendOfZeldaSkywardSword'' has [[spoiler:[[TheManBehindTheMan Demise]]'s hair]].
* ''VideoGame/MetroidPrime'' has several types of glowing mushrooms throughout, including ones in the Phazon Mines that are large enough to serve as platforms.
* The Sylvari race in ''VideoGame/GuildWars2'' are bioluminescent, intelligent plant beings. Did we mention that they're a playable race?
* In ''VideoGame/CivilizationBeyondEarth'', any late-game [[BioPunk Harmony]] colony will develop technology with lots of glowing blue lines on them. This is also true for the Harmony colony's leader, as they presumably genetically modify themselves.
* ''Videogame/MetalGearSolid3'' has the glowcap mushrooms that will recharge Snake's batteries when he eats them. Yeah, it doesn't make much sense in universe either. [[MissionControl Para Medic]] justifies it as likely being [[ClapYourHandsIfYouBelieve a placebo effect]]. That doesn't explain them functioning as an ImprovisedLightningRod against [[ShockAndAwe Volgin's lightning bolts]], though.
* The monsters of ''Videogame/{{Evolve}}'' glow brighter the higher their armor. They come in variety of colors, with Goliath being red, Kraken blue, Wraith a white-ish pink, Behemoth orange, and Gorgon a pale green. For non-monster examples, the blitzleopard and mammoth bird wildlife have this as well.
* In ''VideoGame/{{Battleborn}}'', the [[GreenSkinnedSpaceBabe green skinned]] [[FishPeople fish]] WarriorMonk Alani is capable of glowing her eyes and the tattoos on her body in a manner to certain bioluminescent deep sea fish.
* ''VideoGame/{{Starbound}}'': Bioluminescence biomes are full of glowing plants, glowing rocks, glowing critters, and glowing chests that may contain blueprints for glowing furniture. Slime biomes are full of glowing slime pods. Florans like to illuminate their homes with glowing plants that give off a muted green light (because they have a profound fear of fire, being plant beings). The ocean floors are lit with "oshrooms", or ocean mushrooms.

[[folder:Web Comics]]
* In ''Webcomic/{{Homestuck}}'', when [[spoiler:Kanaya]] becomes a [[spoiler:rainbow drinker]], she begins to glow. [[spoiler:Her dancestor, Porrim,]] also bioluminesces, though she is better able to control it.

[[folder:Western Animation]]
* ''WesternAnimation/StarWarsTheCloneWars'': In Season 4's Umbara arc, the titular planet is [[AlwaysNight completely enshrouded in darkness]], so a lot of the native plant and animal life bioluminesces.
* ''WesternAnimation/TheDeep'': In one episode, the Nektons encounter a species of [[spoiler:giant hermit crabs]] that glow bright blue.

[[folder:Real Life]]
* The protein [[http://en.wikipedia.org/wiki/Luciferase Luciferase]] and its relatives are the cause of natural bioluminescence, for example in fireflies. It has been put into other creatures to create glowing bacteria, etc.
* A more famous but unrelated protein is [[http://en.wikipedia.org/wiki/Green_fluorescent_protein GFP]] (abbreviation for [[ExactlyWhatItSaysOnTheTin "Green Fluorescent Protein"]]). Its derivatives have been established as common tools for scientific research. It's not true bioluminescence: the protein is merely fluorescent, so it only glows under a light source. [[https://en.wikipedia.org/wiki/GloFish GloFish]], zebra danios genetically engineered to produce this and similar proteins, are marketed as aquarium fish by [[InvokedTrope invoking]] this trope in real life.
** One day, you too can have [[https://www.newscientist.com/article/dn17003-fluorescent-puppy-is-worlds-first-transgenic-dog?DCMP=OTC-rss&nsref=online-news a glow-in-the-dark doggy!]]
* Ravers and UsefulNotes/{{Cybergoth}}s have a liking for glowsticks and clothes that imitate bioluminiscence. While it's definitely running off the RuleOfCool, there's also a functional reason behind it: Supposedly, the glow from these sources have a soothing effect on the mind, reducing the chances for a [[MushroomSamba Bad Trip]]. Considering that these subcultures have a particular leaning towards psychedelic substances ...
** There's also the practical side, in that a dark club is, well, ''dark'', which can make it difficult to see people in general and ''especially'' difficult to identify their faces. The faint glow of a glowstick may or may not be enough to illuminate facial features, but if you can remember the combination of colors and kinds of glowing clothing your friends are wearing, you may not need to see them. And if nothing else, it's easier to avoid accidentally slamming into another person if they're glowing.
* True to the ''Literature/LifeOfPi'' example, there are bioluminescent plankton that inhabit some waters, and glow when agitated or touched. A real time example can be seen [[https://www.youtube.com/watch?v=7kyP0XsF0zM here]].