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"Osamu Tezuka was educated as a doctor, so the stories are rich in medical knowledge and experience. Except, of course, when Tezuka decides that it would be more fun to just make crazy shit up. Which is pretty much constantly."


Acceptable Breaks from Real Life biology.

The work contains things that are biologically impossible - often skirting the Critical Research Failure level from the era the work was created in, except the biologically impossible things are needed for the premise of the work, and the work is better for having them.

Badass Normal characters would not be half as fun if they didn't sometimes do things that no truly normal person would be able to do. We are willing to Hand Wave the existence or seriousness of flesh wounds and concussions if it means our favorite protagonist will still be able to do his stuff next week.

We can't have Fantastic Voyage Plots or attacks of the fifty-foot whatevers without breaking the Square-Cube Law, and those types of stories can be fun. We can't have vampires or zombies without breaking a few rules of biology (there's no such thing as unbiology).

If a show which normally has a naturalistic bent wants to deal with phenomena that are normally considered supernatural - say, telekinesis or mind-reading - and treat the phenomena as real, they have to do this with a few dashes of Techno Babble if they don't want to invoke Skepticism Failure. If the hero is by nature a skeptic, then you do not want to invoke Skepticism Failure without a good reason.

We don't normally want radiation to simply do what it does in real life, unless you want a Downer Ending before the work has had the chance to begin. We want genetic engineering to do things it isn't known to do in real life, and we don't always want to wait a generation to see the effects. We sometimes want the fast action of a subtle Lamarck Was Right.

We like the ease of identification Identical Grandsons permit when Time Travel or flashbacks are needed.

Early on, such things get worked in by Rule of Cool or Rule of Funny if they aren't inherent in the premise. At their height, it can become Reality Is Unrealistic: even if the writers do know biology, they work things that would Fail Biology Forever in because the bulk of the demographic want the inaccuracy.

A Sub-Trope of Rule of Cool. A Super-Trope of Funny Animal Anatomy.

Compare: Art Major Physics.

Contrast: Hollywood Science; You Fail Biology Forever; Dan Browned.

Examples of Art Major Biology include:


  • Almost all modern examples of Nuclear Nasty, where it's clear they don't actually think radiation works that way (I.E. creating monsters) but are doing it merely for the sheer Rule of Cool.
  • Likewise, practically every example of the Zombie Apocalypse genre requires that viewers ignore the issue of where the living dead get their capacity to move, if they lack a metabolism to generate energy and their tissues are so decayed that muscle contraction and neural signaling shouldn't be possible. Even variants in which the "zombies" are biologically alive tend to neglect things like the ravening hordes' need for water or rest.

Anime and Manga

  • Osamu Tezuka, the author of Black Jack, was a qualified doctor but freely admitted to ignoring medical accuracy in the interest of telling a good story. For example, the title character was able to get an artificial daughter by grafting a highly differentiated teratoma to a synthetic frame.
    • This was also a major story point in Phoenix: Sun, in which the protagonist is tortured by having the skin of his head replaced with the skin of a wolf and then left to die. Against all biological possibility, the graft takes hold, and he becomes a Petting Zoo Person who can talk to animals and spirits. Even more impossibly, by the end of the story, the wolf skin finally rots and falls off to reveal that his old human face has grown back under it.
  • Franken Fran does this. The roots of the stories are usually based in reality, but then it gets tweaked until it will ruin your dreams for the next month. Given that the main character is a Cute Monster Girl and her sidekick is a cat with a human head, you have to give somewhere.
  • The whole Apotoxin plot in Detective Conan, which stated the Million-to-One Chance Fountain of Youth (and for the other 999,999, poison) acted by initiating an uncontrollable cascade of apoptosis. The apoptosis thing is true, when explained. But where did Haibara and Conan get enough nutrients for their cells to multiply so quickly? And wouldn't their risk for cancer exponentially increase each time they take the antidote? Let alone the antidote... This is critical to the series, mind you.
    • Extensive fan research and investigation has been done into the workings of APTX-4869, and the science behind it is more or less sound, if bizarre and improbable. Apoptosis is the natural death cycle of cells. The toxin also causes, in the victims that survive the poison, activation of telomerase. The initial effect of the poison is easy to explain—the body heats up and the rapidly dying cells become vapor. Eventually, the rapid cell regeneration and rapid cell death balance and cancel each other out, resulting in the "turned into a child" effect. Since the cells of the body are then locked into a perpetual cycle of mitosis and apoptosis, and the dying cells are perfectly healthy, the dead cells are most likely re-absorbed by the new dividing cells as nutrients. Then the dividing cells die, and are absorbed by the next generation of cells, and so forth and so on, possibly for infinity. Going by the stated properties of the poison, and the uninterruptable cycle of mitosis and apoptosis with no reduction in telomere length, it's conceivable that any victim of APTX-4869 is effectively unaging—though trapped in their age-impaired form for the rest of their life.[1]
        • Apoptosis on such a large scale would more than likely result in TLS in the initial phase of APTX-4869 in the scenario described above. Lengthened telomeres do jack-all for acute end-phase renal failure. On the other hand, we need a live protagonist...
    • And none of this explains why the new form would be identical to their actual past childhood form. But you've gotta admit, it's convenient.
    • Nor does explain the simultaneous and proportionate shrinkage in all the non-cellular components of the body, such as bone matrix or collagen fibers.
  • Bio Meat: Yuki Fujisawa's whole plot is solely made possible thanks to the basic design of the Extreme Omnivore mouths on legs, which defy any understanding of any digestive system, not to mention their creators' common sense. The American version uses slightly more common sense, but still circumvents all current biology courses.
  • The bloodline powers in Naruto being part of people's DNA is just a justification for people having powerful abilities that no one else can copy. When a dude pulls out his own spine to use a Whip Sword we have officially thrown all laws of biology out the window. For that matter, any of the result of Orochimaru's experiments and surgeries: you should not be able to move your arms if you have high-powered air tubes running through them, surgery cannot let a human sweat silk that turns rock-hard, and an enzyme should not let you turn body parts into weapons and a jetpack, but Zaku, Kidomaru, and Jugo wouldn't be anywhere near as interesting if they couldn't.
  • In Monster, at one point, a prostitute who has been shot in the gut (one of the most lethal ways to take a bullet) walks to a dingy clinic, where Dr. Tenma, trained as a neurosurgeon and without a full complement of medical implements, with only an untrained "nurse" to assist him, operates on her injured spleen. And she survives. And that's just one of the more implausible ones. Urasawa told a good story, but he definitely took some Artistic License with his medicine.
  • The entire premise of Sex Pistols manga. It makes no sense, it's not meant to make sense, and if you think about it too much you find yourself wanting to dose yourself on large amounts of LCD + Laudanum, but it makes every plot point absolutely frigging hilarious. It's strange cause it's a BL manga, but it has that sweet mixture of 'awww' and 'really funny' that makes it work. Kinda.
    • Add in that men can get men pregnant, women can get women pregnant, and selling your DNA is a perfectly reasonable practice, and you get some really really fucked up family trees.
  • Toriko thrives on this trope. A gigantic mammoth that the heroes go spelunking inside, searching for the most delicious piece of meat. An overabundance of large predators eating each other. Flowers that detect how Badass you are. A guy with a skeleton consisting of 4000 bones. Animals with any number of trunks, heads, legs... etc, etc.
    • Also all the things they eat. It is cool though.
  • Every fighter in Dragonball Z, but especially the Saiyans.
    • Remember that trained fighters can do things that seem somewhat impossible for humans, and the saiyans are actually an alien warrior species. But yeah.
  • Neon Genesis Evangelion has the bio-mechanical Evangelion, which in real life would not be able to stand up thanks to their legs being too slender. There are a lot of weird biological phenomena occurring in Evangelion (like an Angel's egg being incubated inside a volcano) that are explained via incomprehensible pseudo-science.
  • Junji Ito likes this, and it can be found in nearly all of his stories. A Doll's Hellish Burial is particularly notable for being rife with it, despite being less than ten pages long.


  • Works from the Northern Renaissance (Flanders, in particular) tended to play this trope. Figures would appear slightly larger than they would in real life or a table would be tilted at an impossible angle so we can see everything on it. It's simply the whole of the forms themselves that are messed with, the details are still impeccable and true to life, as was typical of the detailed realism of this time period.
    • Actually, this was due to the simple fact that Northern Europe Renaissance artists at the time did not know about perspective system which initiated from Italy.
  • Psh, if you want to talk about stretching biology in art, go look at Mannerism. The proportions on figures are distorted and stretched all over the place. The church actually cracked down on this style of art because it was considered too weird at the time, and promoted the Baroque style instead.
  • The Cubist and Surrealist movements both made heavy use of this trope, with Picasso and Dali being two of the most well-known examples.
  • Sort-of case: Two artists (one of them being John Howe, medieval armor enthusiast) working on The Lord of the Rings would constantly tease and nitpick each other on their respective shortcomings in biology and armor design: "Your creature shouldn't be able to move, let alone fly!" "Well, anyone wearing that armor wouldn't be able to move either!"

Comic Books

  • The X-Men are all "mutants" because of one gene being wonky. Let's just say there are loads of reasons it doesn't work that way, to avoid a wall of text.
    • The short version is even if you disregard everything else all mutants should have the same power.
      • A wonky gene that allows some mutants to time travel, control the electromagnetic spectrum, and modify worldwide weather patters. At least guys like Spidey and the Fantastic Four had their entire genetic material modified (not that makes much more sense, but still)
  • Booga from Tank Girl. He's a kangaroo-man ultimate fighting machine bioengineered thing... made from a dog? Who cares? He's awesome.
    • That back story exists for the movies, the comic doesn't even bother justifying why he exists.
    • Tank Girl also once had a Half-Human Hybrid baby with her tank.
  • The new origin that Alan Moore devised for Swamp Thing after taking over fulfilled three purposes. It allowed Moore to account for the character still being alive after being filled with ammunition. It put a new spin on the character—it was now a plant given human form rather than a human turned into plant. And it was freaky cool. It was also based on a theory that had been disproven shortly after the claim was first made, but Moore wasn't working for research grants.
    • The squid from Watchmen. Granted, it didn't evolve, but why did Ozymandias not create a more probable creature, if he had to fool the entire world? If anyone studies this thing AT ALL, they'll discover that it HAS A HUMAN BRAIN. If they just LOOK at the thing, they'll realize there's absolutely NOTHING protecting that brain. No part of this creature is even remotely plausible. How did Ozymandias pull off this lie?
      • The brain is protected, it just has a bobbly head; it would be found to have a human-esque brain, which might lend credence to panspermia theories in their world. Overall the creature is pretty feasible. Not necessarily likely, but hey. Probably the main reason the lie works is that, well, the beasty is clearly right there, it's clearly not something known to the world of science and it CLEARLY just blew up Manhattan while filling the heads of millions with nightmares about its homeworld. Either it is actually an invading alien or someone put an inordinate amount of work into its creation and proceeded to redefine atrocity for no apparent personal gain. If you tell a lie big enough...
      • Also, since the official line is that it's from a parallel universe, if anybody ever did a DNA test and found out it was an enhanced clone of Robert Deschaines, Ozzy could just explain the genetic similarities away as the thing being Deschaines' alternate universe counterpart.
  • The story "La Nuova Razza" from the fumetti Terror Blu is about sperm that are super-intelligent, can TAKE OVER YOUR MIND by slipping into your brain(?!), are the size of tadpoles, have eyes and mouths (with teeth!), devour human flesh, and—wait for it—SEXUALLY REPRODUCE.
    • Sounds like somebody should have used a condom. Or did they somehow eat that as well?
  • Kingpin. 2% body fat, 350 pounds of muscle. Can beat superheroes in hand-to-hand combat. AND IS COMPLETELY "NORMAL". He's not a mutant, there is no Applied Phlebotinum, there's no magic...just another Charles Atlas Superpower. He can CRUSH a man's SKULL with his entirely "normal" HAND. But damn if it isn't a cool version of Stout Strength.
  • If Giant Man were to actually grow to his full size, he'd be unable to move and all his bones would be crushed to powder. By an elementary equation.
  • The Teenage Mutant Ninja Turtles have essentially had the bodyform and biological processes of a peak human written into their DNA. For instance, they sweat, have a humanlike heat signature, walk upright, can metabolize human food, have thumbs...


  • Alien: The creatures are so cool, it's easy to overlook the impossibility of the fast growth cycles (even before being sped up in the Alien Vs Predator movies) no matter how much it ate in that time, the fact that a creature outside of Earth is compatible with species from Earth even as a parasite, that silicon-based lifeforms aren't actually likely due to how silicon bonds, and how blood like that can work. Basically these things are powered by Rule of Cool and Rule of Scary.
    • According to one of the many backstories for the Aliens, they are bioweapons designed to impregnate anything using any orifice and can survive even on airless planetoids so long as they eat something takes a complex series of chemical reactions occurring in their bodies.
    • Another of the theories regarding their backstory is that they were actually designed by Weyland-Yutani as a bioweapon for use against humans, which neatly explains away a lot of the issues.
    • While a xenomorph as a parasite is about as likely as a human male getting knocked up by pollen, merely having a silica exoskeleton doesn't mean they're silicon-based life—many plants, and some animals like sponges, use silica as a structural element. Of course, if the dialogue explicitly stated them to be silicon-based, the way it explicitly states them to use molecular acid as a respiratory chemical (which would probably only evolve if their planet's evolution followed the Rule of Scary), then it's Hollywood Science.
  • The Thing: This and Rule of Scary.
  • Although there is no official explanation given as to the how the Rage virus in 28 Days Later works after infecting a victim, the idea of a virus infecting its host after a single heartbeat places a pretty heavy strain of the Willing Suspension of Disbelief any movie requires. Of course, since it doesn't affect the ability of most people to enjoy the movie, it doesn't matter all that much.
    • It goes a lot deeper than that. The infected don't eat, they don't drink, it's debatable whether or not they sleep, and they're constantly vomiting copious amounts of their own blood. How could they possibly live for a total of 28 days before falling over dead from starvation?
  • Arachnophobia, where a giant South American spider mates with a common North American spider. Taxonomically and size-wise, this is like a female mouse and a male giraffe not only getting it on, but having completely healthy mouse/giraffe hybrid babies. Sure, there is a lot of size variation between sexes in many spiders, but the female is always the big one.
    • Except that most/all spiders don't actually have penetrative sex so relative size doesn't matter much. Some species that do exist have mouse/giraffe size comparatively, though it's true that the mouse would be the male.
  • From Bee Movie:
    • Let's start with a massive case of Insect Gender Bender—male worker bees. Also, bloodsucking male mosquitoes appear. Lots of them.
    • Then the whole process of honeymaking (which in Real Life involves bees vomiting nectar back and forth into each others' stomachs) is depicted as a fantasy Willy Wonka-esque process. Bad, but not critical.
    • Then one bee stings a man.. and survives by putting a plastic toy knife where its stinger used to be. Real bees that lose their stingers when they sting lose their internal organs at the same time—that's why it's fatal.
    • And finally... pollination. Let's be quick: bees don't pollinate consciously; they aren't the only pollination vectors that exist; and you cannot pollinate a flower with pollen from another genus of flower. It's like trying to impregnate a horse with whale semen; it just wouldn't work!
      • Cross-genera pollination is possible, as is cross-genera and even cross-familial breeding of vertebrates.
      • They revive dead plants through pollination, which is akin to bringing someone back to life by having sex with the corpse. Don't knock it—it worked for Fortunato in Wild Cards.
  • In Crank, the main character is given a drug that stops his adrenaline from flowing. This could work. Two problems: in Real Life, he would have died within seconds (this would have left the movie about the length of a film trailer). Also, fear is the most effective way to produce adrenaline.
    • It's Jason Statham. Fear is afraid of him.
    • He would not have died within seconds. Drugs that block the action of adrenaline are frequently used to control hypertension.
      • Uh... no. First thing, drugs used to treat hypertension do NOT 'block the action of adrenaline'. They limit the action of the RAAS system, particularly angiotensin-2 and ACE, to decrease blood volume. They can also decrease heart rate (i.e. beta-blockers) in the case where arrhythmia and tachycardia are a danger, or where blood-volume-lowering meds aren't working. Inhibiting the action of beta-receptors is specifically decreasing cardiac autorrhythmic cell depolarisation across the myocardial synctium, but it does not block adrenalin or noradrenalin action, it preferentially binds to specific muscarinic receptors instead (and only in the heart).
      • Actually, beta-blockers do inhibit the action of adrenaline and are sometimes used to treat cardiac failure; the reason they're called beta-blockers is because they act as beta-adrenoreceptor antagonists. Drugs such as propranolol reduce cardiac output, reduce the effect of exercise on heart rate and can cause bradycardia, which I think is where the movie was going with that. These can be used to treat hypertension, particularly carvedilol and nebivolol as they also act as vasodilators.
    • And, 2. Considering what Jason Statham's character does in Crank, no adrenaline = can't run fast. And then he would have been killed.
    • Also, it's kinda implied that noradrenaline + adrenaline are inhibited, and if that's the case: no adrenaline = no sympathetic stimulation to the heart -> bradycardia. aaaand... I'm gonna stop there...
    • It actually makes a lot of sense. The drug they give him is supposed to inhibit the action of adrenaline, not completely halt its production. The whole Idea of the film is that he keep himself so pumped that he produces enough adrenaline to overcome the block and keep everything running until the drug wears off.
  • Face Off features John Travolta becoming Nicolas Cage and vice-versa through face transplant. Never mind Travolta being 2" (5 cm) taller, or their different hairdos (Travolta gets his hair cut to match Cage's, but we never know about the other). Don't ask how muscles, nerves, and blood vessels are connected so well that facial expressions are never compromised. Or how the surgery is reversed for Travolta's character in the ending.
    • Never mind the height difference - while John Travolta has many redeeming and charming qualities, no-one is going to mistake him for Nicolas Cage in the nude. And yet, Cage's wife does...
        • They put a microchip on the men's larynx to alter their voices. How is never explained.
      • There have been face transplants in real life, but they don't produce faces identical to the donors because many features of a face are the result of the underlying bone structure. In the film, this issue is Handwaved with the surgeons placing special implants under the transplanted faces.
      • And this leads to a question: John Travolta gets his face back in the end and even decides that he doesn't want his old scar back. All well and good, but why would he want his old chubby bod back?
      • If you look closely after the transplant, the surgeon must have gone and individually placed separate and unique hair follicles on each knuckle of each hand for Castor Troy when making him into Archer. Maybe the doctor was just that good.
        • This is one film that would look considerably different if it were remade today!
  • Godzilla is a prime example of this trope. It's best not to think too hard about how a giant radioactive dinosaur, giant butterfly, or half-plant half-Godzilla hybrid is able to exist. Just invoke the Rule of Cool, a bit of Techno Babble, and perhaps the Anthropic Principle (you can't have Godzilla films without Godzilla) and be done with it.
  • The 'farm humans for energy' backstory from The Matrix makes less than no sense. One much better solution for the machines would be to simply burn the humans and whatever they were feeding humans with, the combustion would generate much more energy than digestion (which, in turn, consumes a lot of this primitive energy to keep the "battery" alive).
    • This was due to Executive Meddling - originally the humans had their brains linked together to form a supercomputer.
      • Even that is no excuse. Given computers with a higher computation rate than the human brain within fifty years (assumed in-universe) making wetware CPU's in a future 200+ years from now is entirely pointless. Even if it weren't, they should have just used brains in jars.
      • Always figured it was something to do with the need for active interaction of human neural patterns. Otherwise, why rig them up to the Matrix in the first place?
      • It's been suggested that the scenario as-stated may be due to an Unreliable Narrator, and that the machines are in fact executing the ZerothLaw by keeping the human race neatly bottled up and safe. It goes some length to explaining why the Architect went to the bother of actually creating the Matrix, rather than just breeding up a bunch of brain-dead meat puppets.
    • There's also the question of how people can walk around outside in the sequels, given how the planet's entire complement of oxygen-producing plants would have died off when the sun was blotted out decades ago.
      • Not if you consider the fact there are no animals either, and the only human survivors are in the "batteries" (oxygen via tube) and in Zion (too small population to poison the entire atmosphere in a century).
        • Decomposition of sun-starved plant life and the burning of war-devastated cities would consume the oxygen just fine, even if all animals including humans had been annihilated.
        • And if there is a form of fusion, Oxygen may be created, plus they have to feed the humans somehow.
        • Another possibility, though it is a stretch. There are some bacteria and algae that thrive in low light but produce oxygen.
        • Probably the most likely explanation for the oxygen: It was established that the machines intentionally created Zion to give humans a choice about whether or not to accept the Matrix. They couldn't very well let everyone in Zion suffocate, could they? So, the machines were making the oxygen all the time.
  • A black & white horror movie called Monster on the Campus has the protagonist inject himself with a Coelacanth's blood in order to become a caveman. It's the "evolution" take on Jekyll and Hyde.
  • The Species movies, especially the second one. A film about the difficulties Natasha Henstridge has getting laid...
    • The fate of The Virus-infected astronaut's human victims in Species II: his Evil Spawn go from conception to full term in minutes and then tear their way out of their hosts like chest bursters. This is ridiculous because, whatever alien biology the fetus has, it needs nutrients from its human mother to survive; the human uterus could never supply enough to allow such growth rates. These things need to assimilate as much as nine pounds of material in minutes; even Alien chest bursters usually had the decency to take a couple of hours. Then there's the part where the infected astronaut blew off his own head with a shotgun and not only survived but also retained his memories, which is like smashing your hard drive, getting a new one, and expecting your old files to still be there when you plug it in.
  • The Happening. Let's see. Plants develop the ability to secrete a neurotoxin that makes people kill themselves. All at once. Without anyone realizing. And it's stopped by the Power of Love. This is all risible; unfortunately, it's also all plot-critical.
    • The scene with the man feeding himself to the lions was a great moment of unintentional comedy. In the scene, a lion bites the victim's hand and lightly, almost playfully, tugs the man's arm, ripping it easily out of the socket. The victim remains standing. In real life, the force required to wrench an arm out of a socket would have pulled the man to the ground. Even then, the joint would only be dislocated, the force required to tear muscle, skin and ligament is even more incredible. Apparently, this unfortunate man was made from papier mache.
  • Another film with risible but plot-critical errors: Jaws the Revenge. Most glaring is how the shark decides to kill a family out of revenge, even though the minds of sharks are unable to comprehend revenge. Also, this shark died in the original Jaws but apparently got better. How would it recognize relatives of Martin Brody, anyway? It also is able to travel from Martha's Vinyard to the Bahamas (which is too warm for great whites) in three days. And it roars. And leaps into the air. And it roars.
    • If you take some people seriously, this is all supposed to be averted because this is a MAGICAL shark. The shark in the first movie is also said to have been a magic shark, sort of an avenging spirit out to get Captain Quint because he killed so many sharks.
  • Junior: To demonstrate that a newly improved fertility drug works, it is decided to test it on Arnold Schwarzenegger. Hey, if it works for a man, then it should definitely work for a woman! Though we never see this one used on a female. Since males don't have wombs, Arnie's character has to carry the child somewhere in his stomach cavity... and man, that is one effective fertility drug...
    • A sorry justification for a valid premise (that is, a man giving birth), since a zygote injected into a male bloodstream will happily graft onto the liver and pull nutrients directly from the system. Albeit, it would, of course, have to be born by caesarian. Since we've yet to allow such a pregnancy to carry to term, we don't know all the possible complications, but a successful birth could easily fall into the realm of probable.
      • Especially considering that in some rare cases women have carried babies to term in their stomach cavity *outside* of the womb, if the egg implanted within the fallopian tube or other such unlikely occurrences, it's called Ectopic pregnancy. These pregnancies are considered quite high risk, and usually do not make it to term, but still, they sometimes do. So it's entirely likely that a man could do the same if it was implanted in there.
      • The issue with male pregnancy is not *where* the embryo will grow; as mentioned, a zygote can happily implant itself anywhere it likes and develop to term.[2] No, the real problem is how you'll get it out without killing the father. The placenta implants itself quite deeply into the tissue it's attached to, and removing it is virtually guaranteed to result in severe hemorrhaging. Ever wondered why womens' uteruses grow detachable linings? This is why.
      • So male pregnancy could be a viable option with close monitoring and a thoroughly planned c-section/liver transplant?
        • Pretty much. There has been a case of a woman who had an embryo escape during a hysterectomy that implanted in her intenstines and she carried it to term (delivered by c-section), though it did cause her considerable digestion problems afterwards.
  • Lampshaded in Rio:

 Blu: I'm sweating. I didn't even think that was biologically possible, but look!

Lifts a wing to reveal dark 'armpits'

Jewel: Ew.

  • There has never, ever been an actual self-colored red cat, as a few of the characters in The Aristocats are. This is genetically impossible due to red fur being linked to tabby stripes. There are two red coat patterns that could be mistaken for self reds; a diluted red, or cream, can have tabby stripes that are very faint and easy to look over, especially from a distance. A long haired red tabby might also be mistaken for a self red because the fur length can confuse the pattern. Neither of these shows up, with Thomas O' Malley and the orange kitten, Toulouse are a vivid red and, as far as one can tell, do not have very long fur.
    • Thomas O' Malley might be a self-colored cinnamon cat, but Toulouse definitely looks like a self-colored red cat.


  • Stephen King's Firestarter has pyrokinesis, telekinesis, mind controlling, and other things. All caused by a drug that was administered to several volunteers in their college years.
    • King himself admitted the bullshittiness of this and says this is the reason he tends to avoid going into scientific explanations behind the plot devices of his later books. Of course one of his latest books use the damn ten percent thing.
    • The book itself does mention that the drug itself has affected the parent's chromosomes in some fashion, and she was born after.
  • Hothouse by Brian Aldiss. It has giant insects, man-eating plants, people growing wings after being mutated by space radiation, the entire planet being covered by a single banyan tree, and giant plant-spider hybrids that use their webs to connect the Earth to the Moon. The publisher even admitted that he knew it was ridiculously unrealistic, but still published it because it was awesome. Which turned out to be good move, because it ended up winning a Hugo award.
    • The bad part is that, in his essays on science fiction literature, Brian Aldiss often lambastes other authors who do the same thing (defying scientific facts for storytelling reasons).
  • The Shel Silverstein poem "I'm Being Eaten by a Boa Constrictor" which has also been adapted as a song. It confuses boas with pythons (boas are too small to eat anything bigger than a rabbit). And the song has the protagonist eaten feet first. Granted, if they'd been eaten head first—the way boas normally swallow their prey—the poem would have been much shorter.
    • Maybe the snake was an idiot. Sometimes they do it the other way around. Then they learn why they normally do it headfirst (one time this troper saw a documentary that had captured one doing this to a frog which, thanks to the whole "inflate the throat sac" thing, had gotten the snake to a near-standstill).
  • The Zombie Survival Guide actually revels in this trope, describing the physiological changes undergone by a human who's infected with Solanum. If you disregard the fact that it's talking about freakin' zombies, and the occasional error about living biology (e.g. the 90%-of-your-brain trope), it's not too different from many real pamphlets on medical conditions.
  • Vurt is big on fives. So it has Five Races, five two-way mixes, five three-way mixes, and five four-way mixes, plus one purely theoretical combination of all five races. This means that some two-way mixes can breed with partners that one of their parents couldn't breed with, which is genetically improbable—but since one of the viable pairings is human and dog, it's also probable that They Just Didn't Care.
  • Colin O'Boyle's The Chronicles of Professor Jack Baling has a type of insect that lives in paralyzing gel, a St. Bernard-sized mantis shrimp that walks on land and serves as the living machine for a hyperintelligent cuttlefish named “Gwendolyn,” and that’s just from the first two episodes.

Live Action TV

  • Between the various undead, the injuries people live through and Giles' lack of brain damage from all the times he gets knocked out, Buffy the Vampire Slayer loves this trope. And that's not mentioning Giant Dawn in S8.
  • Farscape is a prime example. And how.
  • The entire premise behind Out of Jimmys Head is a brain transplant. But they managed to save the "Personality Gland" to Hand Wave why Jimmy is not acting like Milt, since everything that makes a person is in the brain.
  • Heroes: Evolution does not work that way (see the X-Men entry above for why).
  • The short-lived series Threshold has 'hyperdimensional radiation' that was was capable of changing human DNA to a triple helix as part of a "xenoforming" plan. The show was never too bothered about scientific accuracy but it did have Data and a sex-crazed midget.
    • It was produced by Brannon "let's mutate Janeway and Paris into giant newts by having them travel at infinite speed" Braga, after all...
  • In a Battlestar Galactica episode (season 2, episode 13), Dr. Baltar heals president Roslin's cancer by injecting her with some cylon/human hybrid blood that is more resistant to diseases because it has no antigens (particles that are recognized as hostile by the immune system) and therefore "no blood type". Therefore, it is somehow capable of destroying a cancer in a very late stage. If Type O negative blood (the real type closest to having "no antigens") could do that, there would be a lot less cancer in the world...
  • The Weeping Angels from Doctor Who, reveling in this and Rule of Scary, literally turn to stone when you look at them. Biology does not work that way, and neither does quantum physics, but you'll be too busy crapping yourself to notice.
    • The Ood carry their brains in their hands. No, there is nothing to protect their 'hand-brains' in case the Ood accidentally drop them or slip on the frozen surface of their home world. This species design is possible, but the designer of the Ood seems to have forgotten that evolution is not so kind to people born with their brains unprotected.
    • This assumes that they were a natural race and not deliberately engineered at some point in their collective past, or the product of some strange parasitic to symbiotic relationship. After all humans have horrible problems with child birth due to relatively large brains, however the advantages of tool use and advanced intelligence mean that it is not heavily selected against.
      • Plus, the brains that they carry in their hands are a sort of secondary brain used for telepathic communication, and are not their main organ. The Ood are enslaved by having these secondary brains amputated to deliberately remove their telepathic abilities, but they remain otherwise fully capable.
  • In the Community episode "Epidemiology" the physician agreeing with Annie's plan to lower the temperature in order to "break the fever and kill the virus". Breaking a fever is all well and good for preventing brain damage, but the fever is the body's defensive response against the virus which was spread among people with presumably normal 98.6 degree temperatures. Bringing them back down to those temperatures they had when the virus was spread in the first place would do nothing against the virus itself, whatever brain damage lowering the temperatures was preventing notwithstanding. The thermostat needs to go at least below 50 F to affect the environment of the virus, by causing hypothermia in its host (it could possibly show up in Pierce and Lenard a bit earlier). And these low temperatures would just be expected to (very slightly) slow the spreading of the virus in the body, not "kill" it (it's pretty hard to kill something that isn't especially alive in the first place). The average virus would still be active, much less capable of reactivation, long, long after the human has died of hypothermia. There is a reason fevers and sterilization techniques use high temperatures, not low ones.

Tabletop Games

  • Warhammer 40000: Space marines, just (acid spitting, one-ribbed, three-lunged, two-hearted, two-stomached, electric skinned, super strength, reinforced skeleton, fast healing, power armored) space marines.
    • It is debatable whether space marines are actually human, with the level of genetic and physical modification they go through.
      • They're actually pretty plausible, given that they're built as much as they are born. The ribs are still separate, they just overlap thus allowing for the necessary movement without all the gaps; The exta organs are installed, not grown in place (which is kinda how we do kidney transplants now) and I don't know where you got electric skinned from.
        • The electric skin is actually an implant called "electoos", a portmanteau of electric or electronic and tattoo. Occasionally found in Techmarines, they're most often used by the folks that train them, the Adeptus Mechanicus. Usually used as direct interfaces with machines, in a pinch they can be used as basically a stun-gun.
    • A couple of editions back, there was a line about Orks having an "algae base" twined around the double helix of their normal DNA. This is, um, exactly nothing like how DNA works in the real world. This line has since been retconned out and replaced with "animal and plant symbiosis" to explain why Orks are green and really hard to kill, which is a bit more plausible and doesn't require a tertiary strand that somehow knows it's algae.
      • Which begs the question of whether alien life would even use DNA.
      • It's entirely possible for aliens to use DNA - humans do, after all. And given that a lot of planets were seeded with life by the Old Ones, it's not hard to imagine they might have favoured a DNA base for their efforts.
    • Other genetic weirdness: Eldar apparently have triple helix DNA. No-one's entirely sure how this would work; it does exist, but it's not all that stable, making it less than ideal for information carrying. Eldar are explicitly a product of genetic engineering by a Sufficiently Advanced Alien race.

Video Games

  • Bioshock. The hero can instantaneously rewrite his genetic structure using plasmids extracted from sea-slug stem cells to give himself elemental superpowers. As if this doesn't break biology enough as it is, he can also freely exchange his old plasmids with new ones or even remove them and store them in a "gene bank" for later use.
    • Admittedly, plasmids are circular DNA molecules that float around, kind of like Mitochondrial DNA. As a matter of fact, it's been theorized that Mitochondria were originally bacteria that were engulfed into other creature's cells but weren't digested. In this way, one could use plasmids and have them replicate, but that would take a lot of time and you'd be stacking plasmid powers by adding more, not switching them out.
      • Endosymbiotic theory is pretty much accepted as the most complete theory for the origin of both the mitochondria and the chloroplast. There are lots of examples of endosymbiotes alive and a rationale along the lines of that could be used. After all, most cells in the human body aren't human at all. It's notable that the sea slug referenced in the game is based on a very real mollusk that "consumes" some algae and integrates their chloroplasts into it's body. From that time on, it never needs to eat again becoming completely autotrophic.
    • On the other hand, actually getting the plasmids into the cells is extremely risky. Current methods of letting bacteria accept plasmids destroys most of the bacteria. Even if there were plasmids in human cells without killing the human, the cell wouldn't even use them because it's not in the right membrane - eukaryotic cells only act on genes in the nucleus and its membranous structure. It's conceivable that the injected plasmids would be flagged for integration in a membranous structure (either the nucleus or mitochondrion) or perhaps come with their own machinery for extra-nuclear transcription. If the plasmids contained RNA, they could potentially translate straight from cellular ribosomes. But still, transposons are fairly rare and very few organisms can readily undergo the horizontal gene transfer, whether through transformation or conjugation, necessary to meet the descriptions found in game.
    • None of these explanations address the fact that one of the plasmids lets the hero shoot bees out of his hands. Even if it were just pheromones he was emitting, where are the bees coming from instantaneously when you aren't in the gardens?
    • Quite simply, the hero is growing them inside his own hand. Nonsensical but definitely frightening.
  • All the gigantified radioactive animals in Fallout. Word of God states that the Fallout universe intentionally runs on Hollywood Science.
  • Eternal Darkness lampshades this trope, as the enemies you run into have no rhyme or reason for their existence. One of the characters is a biologist who gives the beasts autopsies. He points out that most of them have no organs, no blood, no ability to exist- and yet they existed. This might be what drives him insane.
  • Mario & Luigi: Bowser's Inside Story: Any game ever which has you inside a main character for a game long Fantastic Voyage is going to play into this somewhat, and with the puzzles being solved by Bowser's actions on the top screen affecting the parts of his body being explored by Mario and Luigi on the touch screen... yeah. Making Bowser drink water constantly to flood his stomach and makes bones float out of the way? Making him stand in front of an X Ray machine to make various things vanish and appear? Shooting adrenaline at... something to make him a fifty foot monster who can fight buildings and trains? Heck, making his airway freeze solid to solve puzzles? All there, and the game would be a lot less interesting without it.
    • Oh come on, the Mario universe runs on Toon Physics. Expecting anything in the Mushroom Kingdom to make sense is like complaining because Wile E. Coyote didn't die the first time a boulder squashed him like a bug.
  • Pokémon. Just...Pokémon. Seriously, look at some Pokémon species and just try to imagine a skeletal, muscular, or organ structure for them.
    • Try electrocuting Pikachu (or any nonhuman fighter for that matter) in the original Super Smash Bros. Takes good timing with the Pause button to see it, though.
  • The whole business in Metal Gear Solid where the Les Enfants Terribles twins were created as double-dominant and double-recessive for no reason but to give Liquid Snake something to obsess over. Note that, while often commented on, his speech prior to this on recessive genes being "flawed" is entirely correct in the context of the story, since they're being spoken of regarding cloning a man with supposedly superior DNA, not normal reproduction.
    • Except that having a recessive gene doesn't necessarily mean it's not expressed—you could be homozygous recessive. There's also the part where Liquid grossly misapplies Asymmetry Theory. Not to mention the virus that kills people by recognizing their DNA, the two viruses that somehow counteract each other, the guy whose body carries a charge of 10 million volts, the guy who stops a blast of said 10 million volts by firing his revolvers at it, the other guy who's COVERED IN BEES, the one with "photosynthetic" fungus in his skull...
    • This is justified in The Last Days of Foxhound by being a lie to manipulate Liquid by Big Boss. Mantis and Naomi usually serve as the author's mouthpieces on the subject.
    • Completely justified within the canon of the games in Metal Gear Solid 2—according to Emma, the entire public knowledge of genetics was completely distorted by the Patriots (instead of 5,000 genes, the average human has about 50,000), meaning that we are the ones who are incorrect, not they.
    • Kojima even went on record to say that Liquid did not have a firm grasp on genetics, and that the inaccuracies were the result of the character being wrong. The after-credits sequence of the first game reveals that Liquid was actually the superior one all along.
      • Which is total Fridge Brilliance, Liquid survives things that Solid or Naked couldn't, he was genetically modified and Solid was a straight up clone, but Solid, sticking with the theme that you don't have to be bound by genetics, surpassed his fate but Liquid, even though he had every advantage over Solid still got his ass kicked because he couldn't move beyond I don't think Kojima really thought this much into it, but maybe.
  • In Spore, evolution takes place between generations, but your progeny can only evolve body parts that you have previously collected from an existing creature! But it must be noted that Spore can be called an "evolution simulator" only as much as Harvest Moon can be called a "farm simulator"—that is, in a very rough way—and many aspects are simplified or tampered with to appeal to Rule of Fun. In Spore Creatures, you don't even need to mate to create an egg; and the offspring can be incredibly different from the parent creature.
      • When the offspring the player "inhabits" is born, all the rest of the creatures of the same species around it change as well. This and the amount of time on the timeline show that between "mating" and the egg hatching, several if not thousands of years are meant to have passed. Eggs suddenly growing several times in moments still fails.
      • A full list of errors can be found here.
  • In Super Mario Galaxy, the level "Kingfin's Fearsome Waters" consists entirely of an Underwater Boss Battle against Kingfin, a giant shark skeleton. Only problem is that sharks don't have bones. Sharks are cartilaginous fishes, meaning their skeletons are made up of cartilage (flexible and dense flesh, like the stuff that makes up your nose and ears). A shark does not leave a skeleton behind after it dies—its cartilage skeleton decomposes with the rest of its flesh.
  • Gaia Online does this for the Rule of Funny or the Rule of Cool. There used to be a lampshade of it in the Fishing minigame:

 "You might be wondering why you just caught a trout in the ocean. Gaian trout are marine fishes, you idiot."

    • The character Mirai, who supposedly just graduated with a degree in marine biology and sells pet fish for the Aquariums, frequently fails at even knowing what the newest specimens for sale are. This is played for laughs.
    • Evolving items.
    • Megapuberty.
      • And the preceding subplots, in which Timmy was exposed to toxic waste and then mutated into a monster, fused with the Doc, got separated via surgery, grew an evil alter ego, and was separated from THAT with a giant centrifuge.
      • On second thought, let's just say Timmy in general is made of this trope, You Fail Biology Forever, and Refuge in Audacity.
    • Still, Liam coughing up his own kidney in response to an overenthusiastic Heimlich maneuver was ridiculous even for Gaia.
  • Whoever designed Fish Tycoon arranged it so that aquarium fish are not only all the same genetically-compatible species, but also all hermaphrodites. And not hermaphrodites in the "start as one sex, switch to the other" sense that a few fishes do exhibit; no, any two adult fish can knock each other up at the same time.
  • At one point in Cave Story, you have to collect "jellyfish juice", which one would assume is made from the organs of jellyfish. Sure enough, you do obtain it by killing a specific jelly—but it comes pre-packaged in jars, found inside the a treasure chest that the jelly drops when you kill it.
  • Any Final Fantasy game that has a sci-fi backstory may as well be saying "magic!"
    • IV was the first offender. Why are the Lunarians so similar to humans? They come from a different planet!
    • Then along came VII, the biggest offender to date. A viral alien that travels from planet to planet mind-reading the populus? That can mutate them into monsters, instantly re-write its cellular structure to resemble anything, absorb traits of other animals, transfer them between animals, control anything with some of its cells & an insufficient willpower, & do who knows what else? Seriously, a bucketfull of these things literally revived a man from the dead & completely regenerated his body, clothing, & weapon. Then there are the SOLDIERs. I don't care how hopped up on mako they are, the human body simply CAN'T jump dozens of feet in the air, the structures like joints & muscles simply aren't built for it.
    • IX had the Genomes which, for no apparent reason, were essentially humans with monkey tails who could shoot energy blasts.
      • Though Genomes were artificially created, and so it wasn't a "coincidence" as in most cases.
      • The reason is that they're Expies of the Saiyans.
    • Given that the "sci-fi" elements of Final Fantasy are usually of the Magitek variety (the series is even the Trope Namer), this isn't surprising.
  • The Necromorphs in Dead Space wouldn't be nearly as compelling if they were "realistic" zombies. Some of their biology clearly violates what's been established as possible, but instead of seeming silly it heads straight into Body Horror territory.
  • Resident Evil. Not only there's a virus capable of infecting all forms of life, from plants to insects to reptiles to mammals (save rats, for some reason, which serve exclusively as carriers), but all creatures are affected differently by it, without rhyme or reason:
    • Plants will gain the ability to move and will develop new senses.
    • Arthropods will massively grow in size, though without a specific criteria regarding their original size. For instance, bees/wasps will grow roughly to the size of a man's fist, while some spiders will be as big as a man and some twice or three times as big. Moths will grow as big as a car while worms will become as big as a TRAIN.
    • Reptiles and fish will have the same effect, growing in size but without a scale taking their original size into account.
    • Crows will not change at all, though they will acquire the one characteristic common to all infected creatures: aggressiveness.
    • Mammals will become "undead" (save for rats, as previously stated). That is, they'll lose their mind and their bodies will rot. Otherwise, no changes in size or shape will be appreciated.
      • There are various infected humans (usually bosses through the games) that do change in size and/or shape, like Alexia, Nemesis, Birkin, etc. Plus the Bandersnatch enemies in Code Veronica.
    • Note that the previous list only includes those forms of life which had been accidentally exposed to the virus in its pure form. Mixing the virus with blood or flesh will have different effects, the same will occur if an already infected creature gets dosed with the virus yet again, and let's not even mention the creatures which are selectively created on purpose using the virus. Body Horror Up to Eleven!
      • There are at least 4 different strains of virus (T, G, Progenitor, Ancient), quite a lot of variants (T+G, T-Veronica, T-Abyss, Uroboros, Cameron's)...but they all generally have their own personal moments of this trope. Let alone the crazy parasite Plagas.

Web Original

  • The Whateley Universe. In spades, for the same reason as X-men above. Impossible superhero/supervillain powers? Got 'em. Zombies? The Necromancer's certainly got 'em. Werewolves? At least four different kinds. The only thing they don't have is a giant humanoid robot. Okay, they do have it, but the devisers can't get it to walk because of the Square-Cube Law and such.
  • At one point in the fanfic Shinji and Warhammer 40 K, Shinji is required to go through a temple of trials. He invokes this trope during a rant about the trials, complaining that the giant scorpions he encountered shouldn't be able to support their own weight.
  • The Furry Fandom. Granted, many if not all of them are aware it's fantasy, but some people actually do have some qualms about certain anatomical features. One recurring issue is the presence or lack of mammaries on animals that do not have such features in real life; namely Avians and Reptiles. By extension, Dragons (who are often reptilian) and Gryphons (who often have dominant avian features) also have people debate about whether or not they belong.
    • Gryphons also have people arguing that they should have mammaries because they are also part lion; even though one would believe that nursing would be quite difficult with a nice hard beak.
      • While the beaks aren't hard, IIRC, platypi seem to manage just fine (although they don't have nipples...)
    • Another thing that many people overlook is correct sexual and reproduction-related features. Cats, for example, give birth to multiple litters, and due to this also have extra nipples. While the perversion potential of such features would be obvious, I find that even the most erotically-minded furries completely forget these logical facts.
      • It actually exists and is called multiboob. Most furries just don't think it's hot. Even Furries have their standards.
    • Unless they're specifically dressed as an animal which is lactating at the time, even mammalian Furries' costumes really ought to do without breasts, save perhaps some small spots for nipples.
    • Also, digitigrade feet. Except for bears and humans, mammals walk on their toes. Many furries like to remember this fact by having their characters sport (mostly) biologically correct feet. Unfortunately there's a reason we upright-standing humans walk on our heels; once our weight exceeds a certain level, standing on your toes for any extended time becomes very difficult. Either you sink into the ground, or you hurt your feet from the pressure. This, of course, rarely if at all show up in fictional furry-works.
      • Except that ostriches in Real Life have digitigrade feet and walk around just fine despite of having body-mass equal to human.
      • Conceivably, digitigrade feet would work fine if they were large and padded enough. And a lot of furry characters do in fact have over sized feet.
    • Some of the particular sub-fetishes of the fandom take this even further. In particular, the Fatfur/Inflation and vore fetishes marinade themselves in this trope. Trying to approach these with any sort of logical knowledge will just break your mind.
  • Darwin's Soldiers has some of this. X-Men like powers and Hollywood Healing are the most common offenders. Granted, the X-Men styled powers are treated a little more realistically (i.e. it is not one gene but multiple genes that determine the power, organisms have to be created with the powers, etc.).
  • The Global Guardians PBEM Universe featured this. It advertised itself as an "open source superpowered roleplaying universe", which meant that pretty much any explanation for superpowers was useable. Bizarre alien biology as the source of superpowers, not to mention the "mutant" thing, all saw a lot of use.
  1. Don't ask where the temporary cures and the 200% increase in mass comes from, though.
  2. So long as it has room to do so, of course. If it implants inside an organ or a non-elastic tube, both mother and child — child especially — are doomed.