Ape Shall Never Kill Ape

A race, species, or other group feels morally free to torture, maim, psychologically brutalize, capture, destroy, genocide, and generally toy with the lives of "lesser" species while still feeling morally superior by virtue of the fact that they would never do such horrible things to their own kind. Particularly, they would never kill anyone of their own kind, and look down on other races, who prove their barbarity through killing each other.

They don't necessarily think they're morally superior because they don't kill each other. They just think they're better, and the fact that they don't kill each other is indirect proof of that. If they do start killing each other, don't expect them to suddenly realize they're no better (except perhaps for the Defector From Decadence). They've probably got tons more reasons why they're better, all of them as irrational as that one.

This sometimes appears as a Broken Aesop where the Aesop is Humans Are Bastards and the audience is supposed to assume that the group really is morally superior to humans, though in a "they're bad, but not as bad as humans" way.

This is something of a Truth in Television as well, since many of the so-called "barbaric" cultures were only so to the outsiders. Also compare the opening paragraph with humanity's prohibitions on human-abuse vs animal-abuse.

Usually part of Cultural Posturing; also a subtrope of Moral Myopia. See also Thou Shalt Not Kill, What Measure Is a Non-Human?, Even Evil Has Standards. Contrast In Your Nature to Destroy Yourselves.

Anime

 * This becomes a problem in the Mermaid Melody Pichi Pichi Pitch anime with Sara, a mermaid villain that appears late in the first season. When the princesses try to use their Magic Music on her, it has absolutely no effect, since it's apparently hard-wired into their powers that they can't hurt other mermaids. This, however, doesn't prevent Sara from sending them into fits of agony with her own Villain Song The rule doesn't seem to exist in the manga, and the only reason they can't hurt her is because she's just that strong.
 * Appleseed the movie: "Bioroids don't kill other bioroids!" This time they are morally superior to humans, because that's what they were designed to be from the beginning. As a downside they can't feel positive emotions as strongly as humans, either.
 * At one point in After War Gundam X, Tiffa has a psychic chat with some Newtype dolphins, and explains human cruelty to them, since "Dolphins never attack one another". This is utter bollocks, since dolphins are actually well-known in scientific circles for their habit of killing one another for absolutely no reason other than "For the Lulz." Then again, it might be because the anime was made way back in 1996.

Comic Books

 * In Tellos, Hawke at one point manages to get out of trouble by invoking this trope when caught cheating at a betting game. Since it's forbidden for two members of the elven Ulfen race to raise arms against each other, he pretends to want a fight and then happens to remember that this is forbidden.

Film

 * Planet of the Apes: The Trope Namer, specifically Battle for the Planet of the Apes. As the Real Life section shows, this is far from fact among actual primates.
 * Aliens: Ripley appeals to this trope when she says, "You know, Burke, I don't know which species is worse. You don't see them fucking each other over for a goddamn percentage."
 * In the fourth movie, several Aliens tear apart another to acidically burn though the ship. However, it apparently did this voluntarily, sacrificing itself to allow the others to escape. Even if it wasn't, it wasn't petty "murder" but a necessary step to allow their race to survive. That, and these particular aliens had been splices with human DNA, so they weren't like normal Xenomorphs...
 * Whether it's more human or alien, the Newborn at the end viciously averts this. It's first act after being born is matricide. Its second act is to crush a human soldier's head. The only person it doesn't try to hurt is Ripley.
 * Sebastian Shaw in X Men First Class lightly scolded Emma Frost after she knocks Erik off the ship, stating "we don't hurt our own kind".

Literature

 * Roald Dahl's The BFG. Giants is never killing giants; only humans is. In fact, the BFG claims that humans are the only species on the planet that kill their own kind. Not true in Real Life.
 * The Lord of the Rings: Non-villain example: The Hobbits are big on not killing each other. During the Scouring of the Shire sequence, Frodo's orders are not to kill the Hobbits working with the evil Men who have taken over the Shire. To paraphrase him, "We've never killed each other, and we're not going to start now."
 * Averted in The Silmarillion. Elves killing other Elves is considered an unforgivable sin, but at three points the Sons of Feanor kill other Elves in their pursuit of the Silmarils.
 * This is one of the original Seven Commandments of Animal Farm, conveniently discarded when Joseph Stalin Expy Napoleon became convinced there were traitors in his midst.
 * Particularly Anvilicious in The Once and Future King, which claims that ants, termites, and humans are the only animals that make war on each other. This is almost true (chimps also have wars), but just because other animals don't have war doesn't mean they never kill each other.
 * Invisible Man: Pretty much the only thing restraining Ras the Exhorter is that he refuses to kill other black people. At first, anyways.
 * In Poul Anderson's Technic History series, Dominic Flandry is an Agent for the Terran Empire. Kidnapped by an alien race, the alien race asserts that they are far more civilized than the Terran Empire, as they would never betray an oath or otherwise be dishonest (except to other, lesser, races, like humans). He soon has the entire leadership of the planet backstabbing each other, noting that their refusal to admit that they, too, can betray each other if the price is right, is what enabled him to succeed in destroying them.
 * Thieves' World: The purpose of the Blue Star Order is to produce very powerful Adepts to fight in the Apocalypse, so they strictly forbid the killing of fellow Adepts. So Adepts (who are not a particularly savory bunch) don't kill each other, because their kind are superior. This probably skirts a subversion, due to the reversal of causality.
 * In some stories focusing on the Adepts, there turns out to be a catch to this. One of the keystones to a Blue Star Adept's power is an individual secret that, if learned by another magician, allows the learner to claim the Adept's power (and if learned by a nonmagician can often render the Adept powerless anyway). A powerless Adept is useless in the final battle and is thus fair game. So Adepts never attack each other, nor do they conspire for anybody else to... but that doesn't mean there aren't ultimately lethal vendettas going on.
 * In the Pern novels, dragonriders consider killing one another to be unthinkable, because the death of a rider means the rider's dragon dies as well. When an Ax Crazy Oldtimer attacks F'lar, he doesn't dare to fight back with lethal force . Once F'lar knows the situation, he kills without hesitation.
 * Sector General: Justified with the Cinrusskins: as a race of empaths, no sane Cinrusskin has ever killed another as the pain of death is shared with both the victim and the murderer.
 * Chains of Violence: In this Star Trek novel, there are the Tseesk, bird-like creatures who enslaved a human colony. They repeatedly talk about how their society cares for each of them, and how humans in the colony they found were nothing like this - and this somehow gives them the right to make humans into slaves and when humans revolt, the Tseesk declare that humans are too much of a threat to be allowed to exist free, and want to exterminate them. Then it turns out that  Not really friendly to each other, either.
 * Gulliver's Travels concludes with Gulliver visiting the land of the Houyhnhnms, (a race of intelligent horses) who keep the Yahoos (a race of unintelligent humans) as pack animals, somewhat analogous to how people treat horses. The Houyhnhnms, however, insist that they're better than humans because of how humanely and reasonably they treat each other, whereas we're constantly making wars. They don't treat Yahoos badly -- no worse than we treat regular horses, anyway -- but they refuse to try to help human society achieve the level of harmony they claim to have. They don't really have anything to teach Gulliver except that Humans Are Bastards and that Houyhnhnms are great. Considering how ridiculous he makes Gulliver's behaviour after learning this, it's pretty clear that Swift - for all that he was a bit of misanthrope himself - didn't think much of the Houyhnhnms either.
 * Ender's Game features an odd sort of inversion when a major difference between the Formics and Humanity is discovered.

Live Action TV

 * In Star Trek Deep Space Nine, it's "no Changeling has ever harmed another" (until - and they ain't too happy about that, as you might imagine).
 * The Ferengi follow this to a lesser extent: while murder of individuals and the like happens, Quark has a big speech to Sisko in which he points out that while Humans look down on the Ferengi for being greedy capitalists, the Ferengi themselves look down on the Humans and think they're "better". Ferengi never engaged in genocide, slavery, or atomic warfare, which Human history is full of. Indeed, the Ferengi have never even fought a large-scale interstellar war, instead peacefully resolving disputes by (ruthlessly) applying economic pressure and subjugating their own women.
 * Battlestar Galactica: "Humans don't respect life the way we do," from D'Anna after the Cylons have exterminated billions of humans. Caprica-Six clubbing this self-same D'Anna over the head with a rock is later denounced as "the first act of Cylon-on-Cylon violence in our history" (though it's really not) during a discussion on executing human detainees. Hypocritically, a Five shoots Caprica-Six for speaking out against the executions.
 * They've more recently resorted to
 * Moreover, Three's comment is incorrect, as
 * The Cylons justify their genocide of humanity with "they would have destroyed themselves anyway".
 * Special Unit Two: A particularly nasty specimen of Gargoyle (a mass murderer of humans) makes this comment in the pilot episode.
 * The Terrians in Earth 2 are actually incapable of attacking their own kind. A bad guy takes advantage of this by wearing a necklace of Terrian bones, and until it's removed they can't kill him. Of course, when it does finally get taken off, he's dragged underground pretty quickly.
 * The Vampires of True Blood have nothing but contempt for humans and will kill them at leisure if they can get away with it. But kill another Vampire and you are in for a world of hurt.
 * A somewhat interesting inversion in Dark Shadows. The Leviathan are instead forbidden from using lethal force against humans. Though it's more to avoid even larger problems. Or it's supposed to be, but Real Life Writes the Plot, and the storyline didn't fully make sense in that regard.
 * Averted in Kamen Rider Kiva, where the King and Queen of the Fangire are specifically tasked with killing Fangire who betray their race (King kills those who aid humanity, Queen kills those who fall in love with humans). Occasionally Fangire will fight amongst themselves for more petty reasons,.
 * Routinely averted on Walking with Dinosaurs and its spinoffs (including Primeval). The very first episode has a pair of protomammalian cynodonts eating their own young, and it doesn't improve much from there.
 * On Babylon 5, "Minbari do not kill Minbari." But with almost everything regarding Minbari ethics and morality, there are quite considerable differences between what is said and what's actually done.
 * If you click on that link, you will be accusing the Minbari of lying, the penalty of which is death.
 * However played straight with the almost destruction of Earth in the Earth-Minbari War. The Minbari were just about to completely extinguish the human race, when they discovered that Humans and Minbari share the same souls and in a spiritual sense are the same species. So the whole thing was stopped about the moment the orbital defenses of earth were collapsing.
 * Like True Blood, Buffy the Vampire Slayer carries this aspect, but with all demons. In season 4, after being implanted with a chip that shocks him whenever he attempts to attack humans, Spike (a vampire) becomes gleeful when he discovers that he still has the capacity to harm other demons and vampires. He's then ostracized by those who show contempt for anyone willing to kill "their kind."
 * Although given all the demon-on-demon violence we see throughout the series, and even more mentioned in backstories, it appears that the real problem Sunnydale's demon community has with Spike is that he keeps helping the Slayer.
 * Although given all the demon-on-demon violence we see throughout the series, and even more mentioned in backstories, it appears that the real problem Sunnydale's demon community has with Spike is that he keeps helping the Slayer.

Music
"Yeah, you're the reason
 * Glassjaw alludes to this trope with their song "Ape Dos Mil"

I cannot forget this season

Or the lesson how an ape shall not kill ape"

Tabletop Games

 * In a sidebar titled "Ape Shall Not Kill Ape" in the Feng Shui supplement "Seal of the Wheel," it is noted that the Ascended do not look kindly upon members of the Lodge offing each other because they aren't precisely numerous and the loss of even one of their number is a weighty matter, and thus do not suffer those who make a habit of this to live. Only the Unspoken Name, the leader of the Ascended, can issue a sanction order to kill another Ascended.
 * The Eldar in Warhammer 40000. Killing a fellow Eldar is an unspeakable crime (and not just because they're a Dying Race), which helps fuel that whole Moral Myopia about how a single Eldar life is worth the combined rest of all other sentient life in the galaxy because all the 'lesser' species do horrible stuff to each other. Depending on which accounts you listen to, the Tau may also be an example of this trope to a lesser degree.
 * During the Horus Heresy series it is made pretty clear that prior to the Isstvan V Massacre it was considered taboo for Astartes to kill another Astartes, verging on the unthinkable. It is worth noting, however, the original purpose of the Space Wolves, besides taking part in the Great Crusade, was to be the "Emperor's Executioners". As in; killing other space marines. Although the issue has been deliberately kept nebulous, it seems, given the hints in the literature, they may have performed this specific duty at least once before the Burning of Prospero.
 * Werewolf: The Forsaken: Not only does the Oath of the Moon say "The People Shall Not Murder the People," but it's a sin against Harmony to kill another werewolf. Which is tricky, as the titular Forsaken are at war with their fanatical cousins, the Pure, who a) outnumber them and b) don't give two shits about that little provision.
 * The shadow fey of the Ravenloft setting have the Law of Arak, which absolutely forbids them from killing one another. This, of course, doesn't stop them from harming one another in non-fatal ways, or from killing and abusing as many non-fey as they want.

Video Games
""Anyone who fights us is either stupid or on Saren's payroll. Killing the latter is business. Killing the former is a favor to the universe.""
 * The Nathrezim (Dreadlords) in Warcraft, who, out of all the Always Chaotic Evil demons have proven time and time again to be the cruelest, darkest and most corrupt of individuals, are forbidden to kill each other. In fact, disregarding this was the ultimate loyalty test Sylvanas prepared for Varimathras, and.
 * This is both played straight and inverted for the player characters in World of Warcraft. It is played straight in that it is impossible to kill another player who is in the same faction as you (which obviously includes all player characters of the same race as your own character), though you can engage in friendly duels which automatically end when the loser's health gets low enough that the next hit would kill them. It is inverted by numerous cases where the player is not only able but encouraged to kill NPCs of their character's own race who are members of various factions that are not allied with the player's own faction.
 * The Protoss of Starcraft aren't supposed to kill each other, for fear of falling into racial madness. So naturally they engaged in at least three civil wars since the racial madness and didn't go mad. Turns out they were just scared and created propaganda.
 * Similarly, in his inauguration speech, Emperor Arcturus Mengsk of the Terran Dominion says "From this day forward, let no human make war on any other human." That doesn't end up happening, mainly because the United Earth Directorate sent a taskforce to conquer the sector.
 * The video ironically subverts Mengst's speech, perhaps intentionally. Even as he declares that no human should make war on any other human, we see one battle-cruiser destroy another, presumably Mengsk's forces spreading his reach in the sector.
 * Averted in Mass Effect -- members of one race will easily take aim against their kinsman. Shepard at one point can point out that since Garrus is a turian, he shouldn't want to harm Saren (also a turian), but Garrus explains that race is irrelevant with respects to dishing out punishment and little more is said on the subject.
 * Some party members (including Garrus) will ask why Wrex is willing to fight other krogan. There's a little more justification here, as the krogan are on the verge of being a Dying Race at that point. Wrex brushes it off.


 * Averted in Sword of the Stars, where it is revealed that Hiver clans routinely fight inter-clan wars that cause enough deaths to exterminate the human race several times over, and that the Tarka have turned political backstabbing and civil war nearly into an art form by being so accustomed to it. The Liir play this straighter but actually practice what they preach against other species as well (provided they don't cause trouble; getting a Liir angry at you is not a good thing), while the Morrigi really don't care what lesser species do as long as they're willing to trade and don't defile old Morrigi colony sites.
 * Inverted in the fourth Arc the Lad game. The Deimos are treated by humans as monsters, but one character says that they're so monstrous that "they even kill their own kind"--a sign to the Genre Savvy player that they are really a lot like humans.
 * Fallout: Although the Death Claws, America's genetically-engineered leftovers from the all-destructive Great War, are extremely aggressive creatures little better than animals that attack humans on sight, it's implied (from the modified talking Death Claws in the second series) that their basic pack-based society has a rigidly hierarchical, peaceful, ethical pack-based basic society. They were extremely loyal to the pack as a whole, treating it as a family unit rather than having individual families. Fights within a pack are unheard of, and the pack's leader controls many aspects of life, such as choosing and matching female and male deathclaws for reproduction.
 * Gets deconstructed all the way in Arcanum, whose elves claim that they do not kill another elves because if an elf dies "unprepared", his\her soul will never be able to Ascend to a Higher Plane of Existence. (Tarant's elven thugs aren't so polite, though.) Naturally, when Wrath, a dweller of Hidden Elf Village is killed by poison, the first and only suspect is his dwarven apprentice (who also was stupid enough to sign a life-long contract with the elf). It's up to you to prove that Wrath was killed by an elf Sharpe for a woman they almost fought for and whom Sharpe now lives with as husband and wife (almost a perversion in "free-love" elven society) - or dig it even further and discover that "perverted" family idea actually came from Wrath, that Sharpe actually never killed him and that the bastard hascommitted suicide solely to frame Sharpe.

Web Comics

 * Hyenas from Digger are a tribe of hunter gatherers who view non-hyenas as Prey instead of People. If a Hyena is killed hunting prey, the dead's honor is not a major issue. But if Hyena Kills Hyena, then vengeance must be taken, and the status of the original victim is dependent on the status of the one who takes revenge. This comes into play in the plot when Digger, a wombat,
 * In Sluggy Freelance, Aylee comes up with this argument in the midst of a loyalty tug-of-war between her friends and her race. Thankfully she came to her senses after seeing how readily her race will sacrifice each other for a meal.
 * In Dreamwalk Journal killing non-sentient species is justified as long as it's in self-defence. When it comes to sentients, you can rob, cheat and fuck them blind, but causing injury or death is unthinkable.

Real Life

 * Notable aversions:
 * Very much averted with practically every known species of animal. Social animals such as wolves, lions, and chimpanzees are particularly known for killing members of their own species. Many species of rodent commit mass infanticide and cannibalism within their own families. Even plants compete with their own species for sunlight and water.
 * You think dolphins are cute? You think they're the smartest animal, possibly morally superior to humans? Y'know that adult dolphins will sometimes bludgeon baby dolphins (sometimes their own offspring) to death, right? They also kill porpoises for no obvious reason. It's worth noting that this isn't particularly common behaviour, however, so these could just be the occasional dolphin Serial Killer. Still, rethinking that little smile of theirs?
 * Also dolphins can be pretty mean by human standards. Dolphin rape isn't uncommon and there's at least one observed instance of a group of dolphin males killing the offspring of a dolphin female because she wouldn't submit.
 * Among non-mammals there's the praying mantis and black widow spider. The latter's habits are right there in its name. As it turns out, praying mantis females only eat the heads of their mates if they're hungry or under lots of stress, but that's still something that one doesn't do in polite society.
 * It is commonly known that ants keep slaves. After a war (which ant colonies have all the time), the victors will kill the losing queen and enslave all of the survivors from the losing side. Not just absorb them into the drone workforce, either, but coerce them (under threat of violence) to perform the especially menial stuff.
 * Chimps. Dear God, chimps. A male chimp will kill a baby chimp (as long as he's sure it's not his, so it's not a total aversion of this trope) just to put the mother back in heat. The really effed-up part is that she will be a-okay with that and gladly have sex with the killer of her children. (Bonobos, which have sex with pretty much everyone as a means of resolving social disputes, are much less violent.)
 * The above is also true of lions, which means that either Mufasa should have murdered the hell out of Nala, or else she and Simba are the only example of Brother-Sister Incest in the Disney Animated Canon.
 * Lions are one of the first animals mentioned when one talks of horny infanticidal fathers, and it's true when they get to replace the male(s) of the pride. But at least they wouldn't kill their own cubs, and the male plays a small role in raising them (babysitting while the lionesses are hunting). They're pretty much fathers of the year compared to other polygamous species like, say, bears and skunks.
 * While chimpanzees do kill and maim each other with surprising regularity, gorillas and bonobos do not. Gorilla males put on very aggressive displays when they think another gorilla isn't being properly subservient, but rarely attack with serious force. Bonobos usually settle their differences with loving, at least in captivity.
 * When birds sing, it has two purposes: to attract mates, and to warn same-gendered birds that a given location is claimed territory. If a male bird infringes on another one's territory and doesn't leave quickly, they will fight to the death.
 * Plenty of species of snakes will kill and eat members of the same species of them. Sometimes they'll only do it if they're starving, or competing for a limited resource. Other times, they just do.
 * And, of course, plenty of human administrations, both religious and secular, have committed all kinds of atrocities against others, based on whatever criteria. Nazis didn't even treat each other all that well. Chronic Backstabbing Disorder was practically written into the ideology from the get-go.
 * The Snapping Turtle is a really creepy aversion. Its biting power (twice that of a Great White) really isn't necessary for trapping and eating the small fish it usually eats. It is however very useful for eating other hard shelled animals -- namely other turtles including Snapping Turtles. This is a species that evolved to be a more efficient cannibal.
 * Eugenics and other schools of thought that place one part of humanity above another give rise to the idea that "lower humans" aren't really humans at all. It follows that since they are not your kind you are free to treat them like animals. Those Wacky Nazis didn't invent that kind of philosophy; indeed, they probably did more than anyone to make it unpopular (or even unthinkable) through their example. But it's Older Than Dirt; in order to be enslaved a human has to be less of a man than his master, downgraded from a person to a piece of property like a horse or a dog, and slavery is as old as the first civilizations.
 * Not that the majority of slavery hasn't been essentially incidental, without any particularly heavy ideology behind it--just, this is the person who lost at war, this is the person who ran out of money, this is the person whose father sold her...and freed slaves quite often went on to own their own.
 * More recently, this is also what the Duro v. Reina decision opened up.
 * Inverted with the Betta fish. They're incredibly aggressive to their own kind, at times attacking their own reflection. However, for the most part, they leave other species of fish alone. Many otherwise peaceful saltwater aquarium fish cannot be kept with members of their own species due to intra-species aggression. Many other fish, especially aggressive schoolers, play this trope straight. Cichlids also will usually kill most non-cichlid fish as well, but can be kept with other cichlids, not because cichlids won't kill one other but they will (usually) reach a standstill.
 * The entire premise is inverted with the common aphorism that "The measure of a man is not how he treats his equals, but how he treats his inferiors."
 * Truth in Television for humans. The aversion that most sane, moral humans have against killing another human being in cold blood is very powerful, to the point that when we do it we usually find justifications for it, if only to keep from going insane.
 * Keep in mind it's more of a spectrum (similar to the graph the Uncanny Valley is placed on) the less relatable,the more justified. Dogs are a no kill,cows are justified for food,and insects are killed casually-by the thousands.
 * This has also led to cute-er species being saved from extinction verses others.
 * This is also subject to Values Dissonance -- some cultures are okay with eating dogs, cats, and horses, and others consider killing cows to be taboo.
 * Basically, this's trope's existence could be chalked up to Most Writers Are Human, and humans are the only creatures known thus far who can kill their own kind and actually feel bad about it.