History Main / ExtremophileLifeforms

* ''WebOriginal/BosunsReturn'':

* The Jan in ''Literature/AlienInASmallTown'' are [[SiliconBasedLife/OtherElements silicon/carbon lifeforms]] native to a frigid planet with a very thin atmosphere, where they drink liquid oxygen the way we drink water. They find Earth's heat and air pressure painfully uncomfortable, and [[KillItWithWater water is toxic to them]]. Given their preference when visiting Earth, they hang around in the polar regions. The tropics would kill them. Their life-support gear condenses Earth's atmospheric oxygen into a liquid for them.

* In ''Literature/Camelot30K'', the keracks live on a Pluto-like Kuiper Belt object with a surface temperature of 30 Kelvin and only a near-vacuum hydrogen atmosphere. They use oxygen difluoride as a solvent rather than water, and even then they have to use ''uranium'' to keep their bodies warm and pressurized.

* In ''Literature/TheChroniclesOfNarnia'', there's a deep subterranean land called Bism, which is very hot and features such wonders as fire salamanders and fresh gems full of delicious juice. When the characters encounter some of Bism's natives in a shallower layer of the underworld, these find it far too cold, its rocks too dead, and the endless abyss of the sky far too close for comfort.

* In ''Literature/HonorHarrington'', the population of Grayson developped resistance to heavy metals poisoning, enabling them to survive on this planet, although with shortened lifespans.
* In ''Literature/{{Iceworld}}'' by Creator/HalClement, Ken's species come from a planet even hotter than Mercury, where the air is gaseous sulfur and the oceans are molten zinc, and they have to make a crater into a giant parabolic mirror in order to keep their base warm ''on Mercury''. Their researchers are amazed to discover life on a newly-discovered system's third planet, which is so cold the liquid medium is ''hydrogen oxide''.
* The Nusurans in ''Literature/JanitorsOfThePostapocalypse'' are [[IntelligentGerbil based around tardigrades]]. They take naked spacewalks for fun, and are the only species in the setting harder to kill than [[BizarreHumanBiology cured humans]].

Compare to SiliconBasedLife, with which it often overlaps. Contrast EnergyBeings, who can presumably survive anywhere, but whose environmental preferences tend to be simply ignored.

* Captain Tardigrade was a miniseries about a half-man, half-tardigrade who was virtually indestructible, but his selfishness and incompetence would do harm to everyone around him.

* ''WebOriginal/OrionsArm'':

* ''WebOriginal/HamstersParadise'': The cragspringer is a small, theropod-like mammal that inhabits the peaks of a large mountain range comparable to Everest, where they have to deal with freezing temperatures, high levels of UV radiation, low amounts of food and oxygen as well as sheer drops and have developed a number of traits to deal with these issues. They use thick reflective fur to handle the cold and ultraviolet rays, an omnivorous diet and the ability to enter torpor to cope with lack of sustenance, large highly efficient lungs to extract as much oxygen as possible and a gliding patagium and shock absorbing tendons in their legs to handle falls. These same traits allow one branch of their species to become the bird-like pterodents, who are much better flyers than the previous flying animals living on the planet.

-->-- ''Series/StarTrekEnterprise'' ("In a Mirror, Darkly")

* ''Literature/TheLaundrySeries'' speaks of the Chthonians, codenamed DEEP SEVEN, who live in the upper regions of Earth's mantle.

* ''Literature/SectorGeneral'': There's a species of sapient crystals of frozen methane that can only survive close to absolute zero, another who is only comfortable at molten-rock temperature (these two require very heavily-insulated encounter suits to interact with other sentient species), and a culture of {{Hive Mind}}ed [[ILoveNuclearPower radiation-eaters]] who live '''inside''' the space station's main reactor pile.

When our present-day astronomers think about life on other planets, a term that gets thrown around a lot is the "Goldilocks Zone", the range of distances from the parent star where a planet could have liquid water. This is the only range of temperatures where life as we know it can exist. The [[InsignificantLittleBluePlanet only life-bearing planet we know of]] is in Sol's Goldilocks Zone, and all life on it requires water.

* ''VideoGame/{{Halo}}'': Lekgolo are eel-like aliens that thrive in the ring system of a gas giant by consuming metals, can survive in a vacuum and [[ParasiteZombie the Flood]] find them difficult to infect because they can only infect one worm at a time, a trait that [[{{Precursors}} the Forerunners]] tried to exploit in their fight against the Flood. [[Film/HaloNightfall Thanolekgolo]], a type of Lekgolo gestalt group, take this [[UpToEleven even further]] by surviving the [[EarthShatteringKaboom thermonuclear detonation of a starship's fusion engines]] [[VideoGame/HaloCombatEvolved that destroyed a Halo ring]], being able to [[ExtremeOmnivore consume just about anything]], and ending up being the only living thing on a fragment of the ring.

* ''Of course'' real life features extremophiles, although almost none of them are multicellular. There are microbes that live in volcanoes, ocean rifts, under the Antarctic ice...many examples. Giant tube worms are one of the few multicelluar examples of extremophile lifeforms, living deep under the Pacific Ocean around hydrothermal vents and tolerating extremely high hydrogen sulfide levels.

->'''Archer''': We've beamed a Tholian into decon. Modify the atmosphere in there.\\
'''Phlox''': It may take a moment; Tholians have rather extreme life-support requirements. Increasing temperature to 480 Kelvin...

Some alien life in fiction, however, does ''not'' roll that way. ''These'' lifeforms live in [[LethalLavaLand glowing-hot worlds]] with [[MagmaMan molten metal in their veins,]] or on [[SlippySlideyIceWorld icy ones]] with liquid helium metabolisms. They often have vastly different dietary needs, such as [[EatDirtCheap rock]] or [[MetalMuncher metal.]] The planets they live on are generally {{Single Biome Planet}}s by our standards, although they may be lush and varied to local eyes, and their inhabitants may seem like {{Elemental Embodiment}}s. They're likely to be StarfishAliens due to the radically different environment, though they can take more recognizable forms.

* ''Anime/NeonGenesisEvangelion'' has the 8th [[OurAngelsAreDifferent angel,]] Sandalphon, which looks like an Anomalocaris. It was discovered in a [[LavaIsBoilingKoolAid volcano]] in embryonic form, and later ages rapidly to a subadult form, it was shown to be completely unaffected by lava both internally and externally, and was able to swim through it as if it were water.

* ''ComicBook/PlanetHulk'': The spikes are a race resembling [[ComicBook/{{Venom}} the symbiotes]], who naturally float in the vacuum of space and feed off cosmic radiation. They're usually peaceful, but become starved and aggressive in terrestrial atmospheres and become [[ParasiteZombie parasite zombies]].

** ''Venus'' ends with the revelation that such a life form exists on Venus' blisteringly hot surface. It gathers food (such as [[MetalMuncher metal deposits]]) from the surface with snakelike tendrils, while the bulk of the organism lies underground where it's even hotter. The alien has no need for water and consists primarily of a sulfur-based body under a silicone "skin."

** The Skakoans' homeworld has a very dense methane-based atmosphere, and need to wear full-body environmental suits on other worlds -- their atmospheres, besides being toxic, are at a much lower pressure than their internal fluids, which can have... [[ExplosiveDecompression explosive]] results for them.

* ''TabletopGame/EclipsePhase'' features many {{Transhuman}} morphs adapted to extreme environments. Ranging from the "mundane" Rusters adapted to the half-terraformed environment of Mars to Hulders that barely qualify as "biomorphs" and wander the surface of Titan herding similarly modified caribou, and Suryas, [[SpaceWhale Space Whales]] that live in the corona of the Sun.

** In order to procreate and spread their colonies, the Mycon [[HostileTerraforming terraform]] Earthlike planets into lava hell holes. [[spoiler:They were designed to ''stabilize'' Earthlike planets and ''reproduce'' in lava hell holes, but over the millennia got their orders mixed up.]]

* ''Videogame/{{Stellaris}}'': Some species can live on Tomb worlds, created from nuclear wars.

** The actual aliens are usually adapted to environments very different from Old Terra. The first alien race encountered by Terragen life, and one of the most psychologically similar to humanity, the To'ul'hs, originated on a planet that can be compared to either a cool and wet "Cytherean" world or a very hot and high-pressure Gaian world ((i.e., it's somewhere between Venus and Earth). Unmodified humans would quickly die of pressure, toxin or temperature overload on To'ul'h Prime's surface and the aliens wouldn't fare much better on Earth, although they've developed their own tweaks, some of whom are adapted to Gaian environments.

** In the original ''WesternAnimation/BenTen'', Heatblast's species lives on the surface of a ''sun''.

* ''VideoGame/KirbyTripleDeluxe'': Pyribbit, the boss of Endless Explosions is described as living near the volcanoes and thriving off lava and hot rocks.

*** The Tholians are [[SiliconBasedLife silicon-based]] bug-like aliens adapted to environments so hot that being subjected to anything lower than 380 Kelvin -- about ten degrees above the boiling point of water -- will crack their carapace and kill them.