A person is either part of a certain category (such as a certain species or gender) that they do not feel all right with, and so they want to be part of a different category, or the person was assigned a certain category (often against their will) that they never belonged to in the first place, or some combination of both. Because of this, the person may want or need to change their body or nature or both.
In fiction, Trans Nature can take any form, especially in fantasy and science fiction. Note that trying to regain your true form (after having been cursed, for example) does not count. Starting to identify with your new form does, however.
When a character is a fictional kind of Trans Nature, it is often a big part of this character being a hero or villain: Either he's a member of an oppressive/evil group transitioning to become one of the good and/or oppressed people, or we have a "traitor" who identifies with the "wrong" group.
It can also work as an inversion of Internalized Categorism: Bob thinks men/humans are bad, but instead of denying himself the good things about being a man/human or doing bad things because he thinks that this is what being a "real" man/human means, he instead stops being a man/human — magically changing into something else.
Expect the character to be in a world of trouble if there is No Transhumanism Allowed.
May be caused by Humanity Is Infectious, or inversions thereof. In some cases, Trans Nature leads to Humanity Ensues. Note, however, that that trope is usually not combined with Trans Nature instead, the animal resents having been transformed to a human. One very common form of Trans Nature is Pinocchio Syndrome: a robot, living doll or whatever wanting to become a real human.
- We have the fox Reynard who is attracted to female humans and wants to become a human so he can seduce them. This wish is eventually granted by the witches, making him a shapeshifter with a beautiful male human form.
- We also have some cases of regular Pinocchio Syndrome, with Pinocchio himself and some of the wooden soldiers becoming human.
- In Vathara's Walk Through the Valley, Hiko turns himself into one of the less obvious examples of a Cat Boy in fiction. He has retractable Absurdly Sharp Claws hidden under fingernails, Innate Night Vision so acute that he's blind without his Cool Shades, sensory tendrils, parental instincts that almost drove him to kill a friend because she didn't smell or feel right, eternal youth and an interpretation of the original canon's ki-sense that basically makes him The Empath. That is, if they could sense trees and animals. Also, he can project images as well as emotion. He's implied to have a hell of a Healing Factor. Making these changes permanent is a felony in the Confederacyhe worked for a hidden branch of its governmentand the reader is never given a coherent reason why he'd risk prison and the end of a brilliant career to do this; he and Shakku Arai, his partner-in-crime (literally) had invented anti-aging drugs before he took the serum that would have allowed him to restore his banged up knees and bad back without touching his wrinkles...or the middle-aged spread he must have avoided somehow; he wasn't in do-or-die situation; and then there's this weird line that suggests that even if Hiko isn't consciously aware of any species dysphoria, Arai is:
Arai: I hate what I'm doing, yes,... [b]ut you, Hiko - you hate what you are." (A flicker of humor.) "Or I should say, what you were.
- One joke in the My Little Pony: Friendship Is Magic fanfic Asylum has Twilight talking to a donkey who is delusional and believes she's a unicorn.
- King Louis from The Jungle Book, an ape wanting to become a human.
- Another Louis, the alligator from The Princess and the Frog, wants to be human so that he can play trumpet in a jazz band. He doesn't become human, but still gets his wish to play in a band.
- In the Disney version of The Little Mermaid, Princess Ariel of the Mer-people have a fixation with humans, eventually falling in love with a human and becoming one herself. In this version of the story, humans and mer-people are portrayed as equal, so Ariel's transformation isn't about becoming better or worse. The original Hans Christian Andersen version is not so nice. In this version, it turns out that God loves only mankind, so the Mermaid is doomed from the beginning simply for being born as a "lesser" species. Since her quest in this version was limited to trying to reach out to her Love Interest, it's not an example of this trope. Oh, and it fails miserably, too.
- In Avatar, our protagonist takes Going Native to the logical conclusion, ending the movie with literally becoming a Na'vi.
- In Mammoth, our failed Mighty Whitey protagonist falls in love with a Thai woman and is quite shocked that she thinks men are better then women and that it's okay because she can be a man in her next life if she is good enough. His wannabe-feminist preaching fails to impress her.
- Howard Howe, the main villain in Tusk seems to want to be a walrus since he was rescued by a walrus from a burning boat when he was young. He talks about it several times while taking on the hero. Instead, he makes the hero into a walrus for the rest of the film.
- One of Stephanie Plum's nieces wants to be a pony when she grows up.
- The Merry Gentry series has a number of people who want to be sidhe and often mimic them by dyeing their hair an unnatural red or getting plastic surgery to get their ears pointed. The later is laughed at by real sidhe because only half breeds have pointed ears. One of Merry's coworkers in the first book is a former human gang member who rescued a couple of Unseelie nobles in exchange for being made one of the fey. He's now basically an anthropomorphic, bipedal cat.
- In the Isaac Asimov novella (and later film) The Bicentennial Man, the robot "Andrew" desires to be human, so he gets various implants to change his robotic/positronic body and mind into biological parts. He finally gets acknowledged as human by the government, when he dies of old age.
- Averted in Original Sin: It's very popular amongst trendy young humans in the 40th century to undergo radical cosmetic surgery that makes you look like an alien ("body bepple"). The Doctor explains that this doesn't mean they actually like aliens; like many empires, the Earth Empire has a fascination with its vassal states' cultures but contempt for the bearers of said culture.
- In Cornelia Funke's Reckless, the girl known as Fox was given the ability to change into a fox after helping a wounded vixen, and much prefers that form to her original human one. At least until she realizes that she's fallen in love with Jacob (who is human).
- Briefly mentioned in Outcast of Redwall: Jodd the hare was raised by squirrels and wishes to be one, to the point that he ties his tail to his ears in the hope of stretching it longer.
- The Neil Gaiman short story "Changes" has elements of this. A drug designed to cure cancer has the "side effect" of completely changing a person's biological sex. A biological female who takes the drug will become a biological male and vice versa. It's mentioned that the drug has made sex-change operations obsolete, though some people take it to recreationally change sex.
- In Reaper Man, the soon-to-be-dying wizard Windle Poons says at his Going-Away Party that he's considering being reincarnated as a woman. His colleagues are a little bit taken aback.
- The Librarian, of course, is perfectly content to remain an ape, even if his transformation from a human wasn't actually by choice. Colleagues who'd known him before are now of the opinion that he was always an orangutan deep down, he'd just started out looking human due to an accident of birth.
- Discworld dwarfs are facing a kind of cultural revolution of a trans natured kind. Most of dwarf culture centres around stereotypically masculine things, like armour, weapons, drinking and mining. All dwarfs dressed the same, grew their beards long and used male pronouns for themselves. Most of dwarf "sexuality" consisted of finding out what physical sex your boyfriend was before you got married, not that it would change anything. But recently, some dwarfs have been daring to be more feminine. No shaving, obviously, but maybe wearing very slightly lighter chainmail, or a shinier axe. Maybe even lipstick or a chainmail skirt. Of course, since dwarf gender is so optional, it still doesn't mean that they necessarily do have female body parts. Just that they choose to be perceived that way.
- Captain Carrot Ironfounderson, as evidenced by his name, is a dwarf. He is also, through accident of birth, a six-foot tall human king. But he sees no reason why that should stop him being a dwarf, just like adoptive Dads. Nor does he see why some funny crown birthmark, fancy sword and "royal ancestry" should make him have to be King of Ankh Morpork. He would much rather work his way up the ranks of the Ankh Morpork City Watch by the sweat of his brow. This species dysphoria may be what helps him understand Angua, his werewolf girlfriend.
- Speaking of Angua, Discworld werewolves are notably not "human most of the time". They are always a werewolf. They just happen to be human-shaped a lot of the time and wolf-shaped at least some of the time. Meanwhile, Wolfmen are the same but the opposite way around. Many werewolves/wolfmen have problems changing shape, in fact. Some can only change in the moonlight, or not at all, as evidenced by Angua's sister, who could not change into a wolflike shape, and one of her brothers who cannot change into a humanlike shape but chose to pass as a champion sheepdog in Lancre. Apparently werewolves and wolfmen are simply two different examples of the same species (which can interbreed with human and canine biology).
- The children's picture book Goblinheart: A Fairy Tale uses this as a metaphor for transgender youth. Julep is a fairy who insists they're a goblin. Julep meets a younger goblin named Tuck who is the opposite.
- In both continuities of V, alien lizards are evil. Those lizards who side with humanity stop having a real lizard mind, instead developing human personalities/emotions.
- In Star Trek: Deep Space Nine, at least two episodes are about regular humanoid Trill wanting to transition to become "Joined Trill". A Joined Trill is a composite species, with one humanoid component (normally from the Trill race, though a human was briefly joined in one TNG episode) and one symbiont. Becoming a Joined Trill brings on many changes, including a form of reincarnation: You retroactively gain past lives in the form of the symbiont's former hosts and their memories, and after your death you will continue to live on as one of these past lives for subsequent hosts.
- Trill must be trained and prepared for a long time before Joining, if they are good enough to be selected, or they may become a person that is far more like past host personalities than the current host's previous personality. Will Riker, who had no idea what symbiosis was like at all, was entirely submerged without realizing that there was any alternative. Ezri Tigan, a humanoid Trill who was forced into Joining by circumstance, had at least grown up in a Trill culture and though she experienced a rough and prolonged transition period (full of weird cravings and feelings from her past lives), she kept most of her personality. The most immediately jarring part was that her then boyfriend suddenly reminded her of her son from a past life, squicking her out and ruining the relationship.
- Trill society has a strong taboo against Joined Trill carrying over relationships from previous lives. This is to discourage Joined Trill from marrying their partners across multiple lives and/or taking on multiple roles that will perpetuate centuries-long rule of elite Nth Doctors. The general rule seems to also trend to professions that the symbiont has not experienced, in order to make a more Renaissance man.
- In Star Trek: Voyager, the AI called "The Doctor" as well as the former Borg drone Seven Of Nine are both transitioning. Unlike their predecessor Data from TNG, however, they do not want to become humans. Instead, they are trying to grow into something new, despite the Captain's bias towards the concept of their "humanity" being developed.
- It's Always Sunny in Philadelphia has Maureen Ponderosa, who started identifying mentally as cat after having her "death tooth" finally fixed and eventually having too much cats made her snap and begin have various cosmetic surgery procedures done in order to develop more cat-like features and she wants everyone calls her as cat while on trial.
The Lawyer: Maureen, you are the sister of Bill Ponderosa, and it was at your wedding that Liam got attacked?
Lawyer: Your Honor, nothing represents the tragic aftermath more than the dramatic transformation of this woman.
Lawyer: ... Excuse me?
Maureen: As I transition from woman to cat, I must insist on being referred to as a cat.
Jack: Objection. She's not a cat, Your Honor.
Maureen: [hisses aggressively at Jack]
- In Shadowrun, elves are a subrace of humanity. Some normal humans are "elf wannabees" who want to be elves, and sometimes use plastic surgery to make themselves more elf-like. They're usually looked down upon by real elves and other humans.
- There also exist "ork posers" (which can be both humans and elves). Ork posers can also take this route towards being orks, although the flaw description implies most of them still consider themselves their old race and just want to hang out in ork circles because they're cool. Orks don't discriminate between the two and just find them all annoying, though some ork groups will accept posers who act orky enough.
- In Feng Shui, the Ascended are an Ancient Conspiracy of intelligent animals who used magic to become human, and then took over the world to prevent the same magic from being used to return them to animal form.
- In Eclipse Phase Body Dysmorphia is not uncommon due to casual use of Brain Uploading to switch bodies, and the Fall limiting most people's choices in bodies. Fortunately, bodysculpting, including sex changes, is cheap, but it has limits and bodies are expensive.
- One short from Cyanide & Happiness both plays and mock this concept with a grown man who literally dress in a fox costume and thinks that he's a "Pyro" Fox from "forest planet", while his mother is trying to kill him because she can't accept his new identity.
- Critical Role has Nott, the self-loathing good-aligned goblin who believes goblins are all irredeemably evil and who views herself as a halfling trapped in a goblin's body. She uses illusion spells, when possible, to pass herself off as a halfling, and her goal for adventuring is find magic powerful enough to permanently polymorph her into a halfling.
- Gunnerkrigg Court:
- Reynard the Fox also appears in Gunnerkrigg Court, and true to the myth, he fell in love with a human woman. Rather than shapeshifting, however, he convinced Coyote to grant him the power to possess anything with eyes—and he uses it to take the body of a young human male so he can go to the court and woo his beloved...
- There is a Test that, if taken and passed, allows the test-ee to abandon their old nature and become something new. Humans can become animals and move to Gillitie (like the Kershaw family did), while animals and fantasy creatures can become humans and move to the Court (like Red and Blue did).
- El Goonish Shive features regular genderswapping with the aid of magic and a superscience transformation gun:
- Averted by Justin, who dislikes being temporarily female at a transgender birthday party.
- Averted by Sarah, who enjoys being temporarily male for the party, but is otherwise female.
- Possibly played straight by Susan. Her time as a male apparently felt little different to being female, to her surprise. She also trades uniforms with Tedd, because their school has gender-specific uniforms and they both prefer the opposing gender uniform.
- Played with by Tedd, whose androgynous looks cause people to assume that he is a girl anyway. He developed the genderswapping features on the transformation gun just so that he could actually switch back and forth whenever he wanted to, but mostly because he's a Chivalrous Pervert and proud of it. Eventually he is indicated to be gender-fluid, but that he didn't know that was a thing you could be, and just thought his interest in sometimes but not always being a girl was a result of being raised in an environment with regular contact with shapeshifters and eventually having access to the technological ability to switch sexes. Tedd, after being informed it had a label by Grace and given magic to swap genders whenever he feels the need, comes out to some of his friends as Gender Fluid, not that that this changes his/her behavior much. The author and various characters start referring to Female Tedd with female after this, with no complaints from Tedd. That said regardless of form Tedd is largely only attracted to women. (Though transforming via the Transformation gun makes straight swaps Bi, it's apparently only physical, not romantic, as noted by Ellen)
- Subverted by Grace. She has shapeshifting powers anyway and her sense of self has absolutely no ties to outer appearance in any way.
- Played straight to the hilt by Ellen & Elliot! At first, Elliot was Tedd's much more obviously male friend. He also started off normal to counter Tedd's "Mad Scientist" theme, though that soon got replaced with a Magic Versus Science theme when he was revealed to be skilled at "Anime Style Martial Arts" including projecting spells from his hands. He gets hit by the "Venus" transformation (becoming an extremely attractive, long-haired girl for a month), he demands that Tedd get him a quicker cure (so as to avoid going to high school with an attractive girl's body for a month). Tedd finds out about a crystal that gets rid of transformative "curses", which should work, since the gun is based on alien Magitek. They find the crystal and Elliot touches it. Long story short, it split him into two people. "Elliot" who got to keep his name (because he was the male one) gained a hand-beam spell to give people the "Venus" transformation but now has to burn off his excess magical energy once a day by spending a few hours as a woman. "Ellen", who was created from the "curse" that was removed, is permanently a woman now, and only slowly coming to terms with the thought that she might be okay with that. But she still remembers having been a man, mind and body, all her life as well as not being able to date Sarah, the girl she remembers as her girlfriend. She also has the ability to use the anime martial arts but has decided to pursue magic more in order to differentiate herself from Elliot, although she really likes to use her own "Venus" transformation on him.
- Grace's brother, Vlad, is a male bat-human hybrid who can't change into human form permanently because it's too painful. After being hit by Ellen's Venus transformation, he turns into a human woman and is thrilled to be human for once (s/he takes the female part of things in stride, since it matters very little compared to being human).
- Concession mentions species change surgery as a one-off joke, then much later introduces the minor character Clarissa who considers herself a human trapped in an anthro hamster's body, so she shaves her fur and blunts her claws. She is on medication for depression, like many transsexuals.
- In 21st Century Fox there's a couple comics in which a male rabbit undergoes species and sex reassignment surgery to become a female skunk (modeled after the protagonist of Sabrina Online). One of the surgeons states that technology has advanced to the point where they cloned the appropriate reproductive organs for her, but any kits she bore would be rabbits rather than skunks, and the tail was bionic.
- Kevin & Kell:
- Bruno is a wolf who identifies as a herbivore, eventually getting surgery to install extra stomachs.
- While Angelique initially became a rat for legal reasons, she later says she feels more comfortable than she did as a rabbit.
- In Shortpacked!, when Ultra-Car becomes a Robot Girl, she calls herself "trans-chassis".
- Skin Horse:
- When the team first meet Nick, they conclude that because he's human (albeit one whose had his brain removed and stuck in a helicopter) his problems don't fall under their purview. When he refers to the helicopter as his "real body" they decide that since he identifies as non-human he should be treated as such.
- Goes the other way in the "Grillo Parlante" storyline, where Nera and Jonah meet a support group for transgenics who not only identify as normal humans but are trying to will themselves into developing a Weirdness Censor.
- This is a common trait of Heroes of Space in Homestuck. Jade is a member of the Furry Fandom, Kanaya wants to be a rainbow drinker and Calliope wants to be a troll. This applies to none more than Calliope, who is a Cherub and by her species standards is supposed to grow up alone in conflict with an Evil Twin she's Sharing a Body with. Unlike the rest of her species, she was lovingly raised by Gamzee, fostering a love of trolls and a hatred of being a cherub. Circumstances eventually lead to Jade becoming half-dog and Kanaya a vampire, but Calliope's character arc ends with her being married to someone that loves who she is.
- Jess Star from Sam & Fuzzy is a ten-foot pustulating slug monster with Voluntary Shapeshifting powers. She identifies as a human woman in her twenties (to be specific, a human woman with Voluntary Shapeshifting powers) and takes that shape as her Shapeshifter Default Form.
- Uncle Ruckus from The Boondocks, a self-racist black man who believes that he's really (or at least wants to be) a white man; you could call him trans-racial. He even has a dream about going to Heaven and turning white.
- Teacher's Pet is about a dog who wants to be a boy.
- The South Park episode "Mr. Garrison's Fancy New Vagina" is about this trope and later downplayed it, focusing not only on the title character but on Kyle and his dad as well. Mr. Garrison gets a "vaginoplasty" to become a woman, Gerald gets a "dolphinoplasty" to become a dolphin, and Kyle gets a "negroplasty" to become tall and black. In the end, Mr. Garrison wanted a "peniplasty" to become a man again after realizing that he's "just a guy with a mutilated penis". However, his genitalia was used for surgically altering Kyle and Gerald, and since his testicles were used for Kyle's knees, they break, leaving Mr. Garrison as a woman until he grew new genitalia on a mouse.
Doctor: (on negroplasty) It's a fairly common procedure, really. Just the reverse of a caucasioplasty just like Michael Jackson had.
- Afterwards, in the case of Kyle and his dad, this was never mentioned again possibly due to using Garrison's sexual parts without noticing causing them dramatized for not doing this again.
- One episode of The Powerpuff Girls (2016): features a colt who wants to be a unicorn. Bubbles get the Professor to turn him into a unicorn but it backfires and he transforms into a monstrous looking creature. Eventually his mother appears and informs him he really was a unicorn the entire time, it's just his mane covered up his horn.
- American Dad! have couple villains in earlier seasons who have this mindset.
- In the episode All About Steve, there is a (possibly first otherkin villain in cartoon) Tolkien fan who also happens be domestic terrorist. It maybe cryptically implies that he's either literally Bilbo Baggins trapped inside a human body or just a misguided depressed fan who was done with being human by becoming a "dwarf" and believing that human society must be destroyed in order to create his magical utopia modeled after Middle Earth by any means.
- In another episode, Finances With Wolves, there is another villain, an eco-terrorist named Arboreus, that believes he is a tree trapped inside a human body. This is his major excuse for doing these extreme tactics, and he also has plans to replace his private parts with acorns.
- Trans people are assigned a gender at birth, usually based on their physical sex, that does not match their self-identified gender later in life. Sometimes occurs due to Intersexuality, i.e. physically being in between male and female or not fitting easily into one or the other, or on rare occasions when something happens to their genitals such as a botched circumcision. Most often the infants are assigned to be female. The whole situation is very contentious in the Trans community and Anti-trans/Transphobes.
- The small rise of ethnic plastic surgery and "Transracialism" or Transracial is most known for controversy in recent years due to some people thinking they were born the wrong race.
- There are also religious examples, mostly tied to belief in reincarnation — since men have higher social status, many Hindu and Buddhist women openly hope to be male in the next life, while still having an entirely female gender identity in this life.
- That kind of "trans nature" is pretty common in patriarchal cultures. In some rural regions of Albania, women can, if they have no brothers or other male relatives, go through a ritual that makes them men for the purpose of the law, and enables them to get all the benefits awarded to males, at the price of never being able to have children or marry, as "sworn virgins". Those women are usually not trans as it is understood in the medical sense, they're fine with a female body, just not with the oppression to which they are subjected - and sometimes they're forced to officially change gender because the family needs a male head. It is slowly dying out as society becomes more equal.
- Otherkin. To quote WikiFur, "Otherkin are those who believe that their physical forms do not define or fully encompass their mental states, personality, psychology, or spiritual nature." See the full article here.
- And some furries or "Furry lifestylers" as well. These most often take the route of reincarnation much like the aforementioned religions or people waiting for biotechnology to become real life Petting Zoo People. Comparing them to the above Transsexuals is considered a Berserk Button to most trans groups.
- A third piece to this puzzle would be anyone with other extreme views on body alteration. Some body art and cosmetic surgery won't get you any out of the normal attention, but some do cross deeper inside. People who partake in transforming themselves into living dolls, have overly tattooed or pierced bodies or have done something considered a "self mutilation" can all fall into this category. Any such people clearly follow the philosophy a human should alter their body to how they prefer it to look. Even where there are points of similarities, there are significant portions of the trans and furry communities that want nothing to do with them and probably vice versa note