History Main / HumanOutsideAlienInside

* ''WesternAnimation/TheOwlHouse'': "The Intruder" reveals that aside from having pointed ears, witches also differ from humans by having a "bile gland" attached to their heart that lets them channel magical power. "Separate Tides" also reveals that a lot of their food is undigestable for humans.

** They can also convert their body into an equivalent mass of spiders, and stick parts of their consciousness and memories in certain spiders. (A particular Merit allows them to be true hiveminds instead.) They can also steal another human's body by having a few small spiders enter the mouth (or other orifice) and devour them from inside, turning the bodymass into more spiders in the meantime. These are heroic player characters, by the way!

* Classic comic example: An alien woman in an old [=EC=] title did in her earthling husband on her wedding night after seeing his navel and realising he was a mammal. This entirely Caucasian-looking blonde-haired woman with [[NonMammalMammaries nice, perky breasts]] was supposed to be from an egg-laying species who find the mammalian lifestyle disgusting.
* The Kree of the MarvelUniverse have black-widow-like mating practices; females are "neutered" to prevent this. They also require a special gas or other life-supporting technology to breathe on Earth.
* Franchise/{{Superman}} has many handwaves for his many powers, but the main thing to consider is his kryptonian ability to emit microwave radiation and levitate, all from exposure to higher energy solar radiation.
* Most if not all of the ComicBook/LegionOfSuperHeroes must fall into this category; Triplicate Girl/Duo Damsel and Matter-Eater Lad being two of the most obvious examples.
* The [[ComicBook/UltimateFantasticFour Ultimate Universe]] version of the ComicBook/FantasticFour used some decidedly non-human anatomy to [[RequiredSecondaryPowers explain some of the team's powers]]. Reed, for instance, looks fully human when not using his stretching powers, but no longer has internal organs, merely possessing a "bacterial stack" in its place. Oh, and he no longer craps.

* A rare inversion: The three-eyed altered humans who show up in a few issues of ''ComicBook/TomStrong'' can no longer eat at least ''certain'' terrestrial foodstuffs without getting the pukes. However, coffee doesn't bother them...and normal humans seem to be able to eat ''their'' food [[NoBiochemicalBarriers without adverse effects]].
* Karolina Dean and family from the ComicBook/{{Runaways}}. On the surface they look like normal humans, but their bodies apparently store and then expel solar energy and a dying vampire notes that Karolina's blood "burns like sunlight." This never being picked up by a doctor could be explained by her parents' apparent natural living kick, which might have involved never taking Karolina to a doctor or having her vaccinated.
* Some aliens in Comicbook/{{Empowered}}'s verse have two left kidneys. And one kind of alien (maybe the same one) has kidney equivalents that filter the bloodstream using coherent light - essentially, [[EnergyWeapon Frickin' Laser Beams]].
* Teddy Altman from ''ComicBook/YoungAvengers'' is a [[NonhumanHumanoidHybrid Skrull-Kree hybrid]]; while his default form is that of a pink Kree (essentially a Caucasian human) his internal organs are those of a Skrull. It saves his life while being tortured, as during the vivisection, his internal organs kept rearranging themselves to avoid being cut even with Teddy being unconscious.
* Mutant powers in the Marvel universe with on occasion be cursorily explained with physiological differences. Mutant psychics will be said to have different brain structures, while mutant speedsters like Quicksilver or Whirlwind will have explanations detailing the RequiredSecondaryPowers needed to survive their speed; the latter even being said to have body fluids that are thick like motor oil.

* Starfire of the ''WesternAnimation/TeenTitans'' (at least, the TV show). Aside from her decidedly orange skin and her ability to fly and to shoot energy from her hands and eyes, she has nine separate stomaches, an oft-unused [[OverlyLongTongue long, prehensile tongue]], a temporary but extensive {{Metamorphosis}} triggered by puberty, and [[PlotAllergy a nasty allergy to metallic chromium.]][[note]]metallic chromium is used extensively in metallurgy on this planet from alloying to plating. At minimum Starfire couldn't get within a hundred feet of a car, [[WildMassGuessing unless it's just N allergenic in powder form, like dander]][[/note]]

* The WitchSpecies from ''Series/SabrinaTheTeenageWitch'' have some incredibly bizarre biological quirks, far beyond what their magical powers would imply. Possessing certain character flaws can inflict them {{Anvilicious}} pun-based mutations (for example, a witch who acts "spoiled" will start to dissolve into foul-smelling ooze), their magic needs to be extracted and "tuned up" regularly to function properly, and their wedding vows involve exchanging ring ''fingers''.

* The inhabitants of the world of ''Anime/{{Simoun}}'' are otherwise indistinguishable from Earth humans, except that they're all born the same sex, develop feminine bodies when they reach adolescence and choose a sex at age 17 by wading through a particular spring. Reaching such a state through evolution is extremely unlikely, but this is a fantasy/steam-punk series that needs a justification for making all the main characters SchoolgirlLesbians.

* {{Superman}} has many handwaves for his many powers, but the main thing to consider is his kryptonian ability to emit microwave radiation and levitate, all from exposure to higher energy solar radiation.

* ''WesternAnimation/TheOwlHouse'': "The Intruder" reveals that aside from having pointed ears, witches also differ from humans by having a "bile gland" attached to their heart that lets them channel magical power.

** The krogan have an [[SpareBodyParts extra set]] of ''everything'', because it helps them survive [[DeathWorld Tuchanka]]. They even have a backup nervous system. And four testicles. Fortunately we don't see this first hand.
*** It is worth noting that the Widow sniper rifle is designed specifically to kill Krogan. You know what else it is designed to kill? ''Tanks''. In the Shadow Broker DLC, You can read some of Master Assassin Thane Krios' notes on how to kill various species; the description for Krogan is a vertiable catalogue of what would be killer blows for any other species, followed by the addendum "Backup method: [[ThereIsNoKillLikeOverkill Bomb.]]"

* The [[ComicBook/UltimateFantasticFour Ultimate Universe]] version of the ComicBook/FantasticFour used this to [[RequiredSecondaryPowers explain some of the team's powers]]. Reed, for instance, no longer has internal organs, merely possessing a "bacterial stack" in its place. Oh, and he no longer craps.

* Parodied in ''Manga/KenichiTheMightiestDisciple'' with [[JerkAss Nijima]], who [[http://www.mangafox.com/manga/history_s_strongest_disciple_kenichi/v03/c023/2.html apparently has some biological irregularities.]]

* ''Manga/{{Parasyte}}'': The eponymous {{Puppeteer Parasite}}s leave their hosts bodies outwardly unaltered most of the time, but alter their biology even when not using their LovecraftianSuperpower. Apart from their BodyHorror-riffic maturation process, they can split their body mass into multiple pieces (although pieces that are too small will wither and die quickly), they're made of a singular type of cell that they can turn into any variety of bodily tissue they need, fire and acids cause them to undergo the equivalent of a grand mal seizure, and they don't know how, or even IF they reproduce.

* The aliens of ''Manga/{{Parasyte}}'' definitely fall under this trope. Apart from their BodyHorror-riffic maturation process, there's the fact that they can split their body mass into multiple pieces(although pieces that are too small will wither and die quickly), that they're made of a singular type of cell that they can turn into any variety of bodily tissue they need, that fire and acids cause them to undergo the equivalent of a grand mal seizure, and that they don't know how, or even IF they reproduce. Although according to WordOfGod, the Parasytes were not necessarily meant to be aliens. The negation of NoBiochemicalBarriers means it's more likely that they originated on Earth. But either way they do have some... [[{{Squick}} interesting]] biology.

* The aliens in the comedy ''What Planet Are You From?'' are just like humans, with only two differences: 1) everyone in their society is male; 2) their bodies can produce shafts of light.

* The natives of ''LightNovel/TheTwelveKingdoms'' are apparently indistinguishable from Earth humans, but instead of reproducing "normally" they are born out of large fruit that grow on special trees. They ''can'' have sex, but it looks like it's for fun and not for reproduction.

* In Film/MyFavoriteMartian it is made clear that the Martian gum only changes the '''outward appearance''' of whoever is chewing it, leaving any major organs or other special biological properties (such as Martin's three stomachs and the "Martian Depression") intact.

* Celty in ''{{LightNovel/Durarara}}'' has most of the same organs as a human, but they're vestigial and nonfunctional (to the bewilderment of a character who vivisects her.)

* Inverted in the 2003 ''[[WesternAnimation/TeenageMutantNinjaTurtles2003 Teenage Mutant Ninja Turtles]]'' series, Baxter Stockman and Oroku Saki [[spoiler:a.k.a. The Shredder]] see a thermal camera image of the Turtles, which looks roughly like a human being's heat signature - only humanoid-turtle shaped. They also sweat. This implies that they have a human-like metabolism. They seem to be Turtle Outside, Human Inside. They also have a full set of teeth, and eat human foods. If you have a turtle, don't give it pizza or Chinese food unless it too is a humanoid mutant. [[RealityEnsues It's not good for them]].

** One episode features Lum and Ten eating pickles and realizing too late that the brine has an effect on them that alcohol does not.
** In at least the anime (episode "What A Dracula"), the Oni can't stand the smell of garlic and are repulsed by those who've eaten it. Ataru explicitly compares Lum to Dracula after proving that, yes, his garlic-scented breath does act like tear gas on her, going so far as to jokingly try and ward her off with a cross after pointing out she hates garlic, has fangs, and bites his neck/sucks his blood.

** The trolls look like [[RubberForeheadAliens humans with gray skin and horns]], but references are made them having insect-like physiology, and young trolls look like grubs. Individuals can have blood of almost any color of the rainbow (in fact, blood color is the basis of their caste system). We're not given much detail about their reproduction, but the act involves filling pails with genetic material--and individual trolls are required to fill pails with two different partners: a pairing based on mutual love ''and'' [[FoeYay a pairing based on mutual hate]]. [[CatchPhrase Troll biology sure is weird!]]

* Played with in Franchise/{{Tron}}. Programs and [[Film/TronLegacy Isos]] resemble humans. Even more specifically for Programs is that they sometimes are a doppelganger for the human who coded them. But when they are wounded, it looks like hunks carved out of their bodies, scars resemble dead pixels on a monitor, and serious or lethal wounds cause them to shatter like safety glass instead of bleed. They feed by drinking energy, and it's implied that their [[TronLines circuitry]] is very sensitive.dldfz

* Played with in Franchise/{{Tron}}. Programs and [[Film/TronLegacy Isos]] resemble humans. Even more specifically for Programs is that they sometimes are a doppelganger for the human who coded them. But when they are wounded, it looks like hunks carved out of their bodies, scars resemble dead pixels on a monitor, and serious or lethal wounds cause them to shatter like safety glass instead of bleed. They feed by drinking energy, and it's implied that their [[TronLines circuitry]] is very sensitive.

* A fairly subtle example: In the ''Literature/ConfederationOfValor'' series, [[OurElvesArDifferent Taykans]] become mature physically, sexually, and (to a limited extent, at least) socially long before they become fertile.

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* No matter the race of the Dragonborn from [[VideoGame/TheElderScrollsVSkyrim Skyrim]], everything about them on a metaphysical level is a fire breathing, flying lizard. This allows them to pull off feats that horrify mortal and dragon alike.

[[folder:Web Comics]]