[[quoteright:213:[[http://shirt.woot.com/offers/you-have-to-try-this-guys http://static.tvtropes.org/pmwiki/pub/images/ascended_to_carnivorism.jpg]]]]
[[caption-width-right:213:[[Film/MontyPythonAndTheHolyGrail That's no ordinary rabbit!]]]]

Sometimes, with CarnivoreConfusion, all animals are [[FurryConfusion omnivores]]. Sometimes, only the evil characters eat meat; herbivores eat plants, and "good" carnivores go vegan or [[WhatMeasureIsANonCute eat bugs/fish]]. Sometimes, carnivores eat meat, herbivores eat plants, which is [[PredationIsNatural accepted as the law of nature]] as there's nothing anyone can do short of replacing their digestive system. But in some cases, one of the herbivores, a prey animal, might get upset... might get a little obsessive about the injustice... might "[[AxCrazy crack]]" a little. Followed by the terrifying (or [[BlackComedy hilarious]]) sight of a wildebeest trampling a lion to death and feasting on the corpse.

This trope need not be invoked in vengeance or uprising, but does usually affect a herbivore character that is least a little insane.

A subtrope of CarnivoreConfusion. Contrast VegetarianCarnivore for when a normally meat-eating animal decides to switch to a vegetarian diet.



[[folder:Anime & Manga]]
* In ''{{Tales of the Dark Forest}}'', a half-crazy unicorn decides that if he eats the entire corpse of a human, he can [[PowerCopying gain human powers]], including a digestive tract that can handle meat. [[spoiler:He's right, by coincidence.]]
* The Sheepwolf from ''Anime/KirbyOfTheStars''.
* In ''Manga/PetShopOfHorrors'', a breed of rabbits go about attacking and devouring people.
** And the other species these rabbits take after, the aphid, is herbivorous as well...
* Episode 6 of ''Anime/MichikoToHatchin'' briefly features a fighting bull eating a steak made from an ex-bull.

[[folder:Fan Works]]
* ''FanFic/TheLunarGuardsman'': Luna has long now learned to eat and even enjoy meat, a result of her obsession and fear of disappointing her sister that drove her to return to her as rarely as possible, thus learning to subside on the flesh of the same monsters she hunted.
* ''FanFic/TheImmortalGame'': [[TheDragon Esteem]] indulges in eating meat, which is anathema to most ponies.
* In ''Fanfic/FalloutEquestria'', plenty of ponies (including some protagonists) rely on meat for sustenance, as plantlife tends to be scarce in the post-apocalyptic setting and the other alternative is centuries-old pre-packaged food. Some even prefer it. Cannibalism also occurs, although it's treated as a clear atrocity.
** In the RecursiveFic ''[[Fanfic/FalloutEquestriaProjectHorizons Project Horizons]]'', there's an actual cannibalism ''[[TheVirus virus]]'', which combines [[SanitySlippage increasing mental instability]] with an extreme hunger for protein. [[labelnote:note]] Technically, it's no virus, but a prion disease, like real-world CJD or mad cow disease. [[/labelnote]] Victims are irresistibly compelled to gorge themselves on meat, be it from animals, fellow ponies, or their own limbs.
* In the [[Creator/{{Lopoddity}} Pandoraverse]], ponies from the Oatstralian Oatsback tend to be more omnivorous than your average pony, due to the harshness of their home environment, and even have pointier canines to help eating meat. Bruce, for instance, sees nothing wrong with his catching and eating fish. This doesn't translate very well, culturally--Aerostorm once fainted dead away when he came across a rather bloody Bruce filleting a large trout.
* Remmy Cormo of ''Fanfic/PackStreet'' is a ram[[note]]male sheep[[/note]] with a taste for Bug Burga, fast food made with arthropod meat. Later on he finds out he's an even bigger fan of fish.

[[folder:Films -- Animation]]
* ''WesternAnimation/FindingNemo'' ends with the little green fish from the sharks' meeting gobbling up [[AlluringAnglerfish the Anglerfish.]]
* ''WesternAnimation/HappyFeetTwo'' features a krill who's tired of being at the bottom of the food chain and wants to "eat something that has a face".
* ''WesternAnimation/WereBackADinosaursStory'' apparantly features a Triceratops named Woog and a Parasaurolophus named Dweeb, who both for some reason actually like to eat hot dogs.
* In the Disney film ''WesternAnimation/TheWild,'' The wicked wildebeest Kazar is tired of always being hunted by predators, so he decides to to make himself the top of the food chain. By eating a lion, no less. Kazar's Lieutenant, Blag and the rest of the wildebeests, on the other hand, don't really want to become predators, but Kazar abuses and threatens them. [[spoiler: They stand up to him at the end of the climax]]
* The "Rite of Spring" segment in ''Disney/{{Fantasia}}'' featured ''Plateosaurus'' (possibly omnivorous also in RealLife) and ''Kannemeyeria'' digging for clams to eat.
* ''Anime/RingingBell:'' [[spoiler:The last part has Chirin turn into a demonic, flesh-eating ram upon becoming an adult.]]

[[folder:Films -- Live-Action]]
* And of course, don't forget the KillerRabbit of Caerbannog from ''Film/MontyPythonAndTheHolyGrail''.
* A similarly-psychotic rabbit appears in the 2010 horror flick ''Film/{{Primal}}'', although it's killed before it can rack up a body count.
* In the first act of ''Film/TwoThousandOneASpaceOdyssey'', TheMonolith is sent by unseen alien {{Precursors}} to teach the ancestors of the human species to eat meat so that they can survive a drought. (While doing research for the novel, Creator/ArthurCClarke consulted Creator/IsaacAsimov about the biochemistry of turning herbivores into carnivores, but none of this shows up in the final story.)
* According to the ''Franchise/StarWars'' wiki page, the bovine-looking alien that was used among the other alien creatures to fight the captured Jedi in the Geonosian arena in ''Film/AttackOfTheClones'' belonged to a species of herbivores called Reeks that were often fed meat for exhibition sports and execution to make them more aggressive. Because they could not thrive on meat, captured Reeks were fed just enough plant matter to keep them healthy.
* The gorillas in ''Film/{{Congo}}'' were forced to eat meat to make them the perfect guards for the temple.
* In the movie ''Film/{{Raw}}'', lifelong vegetarian Justine gets her first taste of meat during a hazing ceremony, and discovers that her mother's dietary insistence wasn't military veganism--it sparks a fanatical obsession with eating meat, especially human flesh...
* The movie ''Film/{{Zoombies}}'' blends this with your standard flesh-eating zombie, in that all the infected animals at the zoo crave the flesh of the living, including what would otherwise be obligate herbivores.

* The creation story in ''Literature/WatershipDown'' has all animal species start out as grass-eating herbivores, some of which were transformed into carnivores by Frith (God) to keep rabbits' numbers in check.
* The [[RhinoRampage rhinoceros]] from ''Literature/JamesAndTheGiantPeach''.
* ''Literature/CryptidHunters'': ''Mokele-mbembe'', a living genus of sauropod, has apparently evolved to be a carnivore in the 65 million years since the dinosaurs' extinction.
* The tie-in illustrated book ''[[Film/KingKong2005 A Natural History of Skull Island]]'' features animals that shared Kong's DeathWorld ecosystem, including a genus of parrots that gave up on the nut-cracking and became scavengers, complete with vulture-like bald heads.

[[folder:Live-Action TV]]
* One episode of ''Series/RiverMonsters'' features a herbivorous fish from the amazon that got trasplated to Papau New Guinea, and after depleting the vegetation the way invasive species do, began supplementing its diet with flesh. This fish, the Red-Bellied Pacu, has human like teeth in a piranha like body, though its its bite is considerably more painful than that of the piranha to which it is related due to it not being designed for that particular dietary practice.

[[folder:Myths & Religion]]
* In the JustSoStory ''The Deer and the Panther Share a House'', after Panther brings home the leftovers of a dead deer, Deer goes out and (with the help of an anteater) hunts down a panther for dinner.
* According to one version of legend, the Minotaur from [[Myth/ClassicalMythology Greek mythology]] was given live humans for food because, as the result of an unnatural union of a human and a bull, it had no natural food and therefore had to eat manflesh.
* The Mares of Diomedes were four horses that their owner, the thracian king Diomedes, had got used to human flesh. Stealing them was one of Herakles' tasks; but not before feeding Diomedes to his own animals.
* According to the ''Literature/BookOfGenesis'', humans, and possibly all other animals, started off vegetarian. After the Flood, God told Noah that he could start eating meat.

[[folder: Puppet Shows]]
* In ''Series/{{Dinosaurs}}'', Earl's boss, BP Richfield, is a triceratops who has been known to eat employees who disagree with him (and [[OverprotectiveDad his daughter's exes]]).

[[folder:Tabletop Games]]
* ''TabletopGame/{{Traveller}} The New Era'' supplement ''Aliens of the Rim: Hivers and Ithklur''. During a military campaign between the herbivorous K'Kree and the Ithklur, the fighting became so bitter that each side started performing atrocities on the other, including the K'Kree eating dead Ithklur bodies.
* In the ''TabletopGame/DungeonsAndDragons'' adventure "The Curse of Xanathon", one of the screwy proclamations issued by an insane king is that horses in his kingdom should be fed nothing but meat, supposedly to make them strong. [[spoiler: This is one of several such orders intended to weaken the kingdom in preparation for a takeover by the evil priest who caused the king's insanity.]]

[[folder:Video Games]]
* In ''VideoGame/OverlordI'', TheCorruption that has swept through the Elven forest has driven the local unicorns mad, causing them to become murderous carnivores -- they're introduced ripping out the guts of dwarven corpses and gorging on the entrails.
* In ''VideoGame/{{D2}}'', protagonist Laura discovers that [[spoiler: she was cloned from the remains of a prehistoric WingedHumanoid]] that was found preserved in a glacier...''inside the stomach of a wooly mammoth.''
* ''VideoGame/BanjoTooie'' has a baby ''Styracosaurus'' with a taste for meat. This becomes HilariousInHindsight in that some scientists now consider ceratopsians to be omnivorous.
* Happens to a human in ''VideoGame/PandorasTower''. The heroine, Elena, was formerly a devout Miko of a religion that prohibits the consumption of meat. Unfortunately, Elena is suffering from the Curse of the Beast, which slowly transforms her into a hideous monster and can only be temporarily quelled by eating the flesh of beasts. While meat initially makes her disgusted and nauseous, she eventually adapts to eating it over the course of the game. If the player neglects to feed her, she becomes desperate enough to start eating animals like birds.
* ''VideoGame/Fallout4'' features Radstags, deer mutated by nuclear fallout into the animal equivalent of ConjoinedTwins -- the creature(s) split at the middle of the spine, so they have two heads and a total of four forelegs, though the middle two are too atrophied to function. The ones encountered in the main game are harmless, with the exception of males or certain variants like Rabid Radstags that will initiate combat if you get too close, but the ''Far Harbor'' DLC introduces Devolved Radstags, which sport pronounced fangs and are actively predatory, attacking anything they encounter.
* In ''VideoGame/PathOfExile'', Yeena in Act 2 mentions that the murderous packs of apes you encounter used to feast on nuts and berries before turning to full-blown cannibalism and hungering for flesh in general.

[[folder:Web Animation]]
* Near the end of the first ''WebAnimation/ThereSheIs'', the rabbit Doki drinks fish juice instead of the usual carrot.
* Carl in ''WebAnimation/LlamasWithHats'' is SerialKiller llama who has eaten human flesh.
-->"I was hungry for hands. Give me a break!"

[[folder:Web Comics]]
* In ''Webcomic/{{Digger}}'':
** A possible subversion; Digger the wombat is forced to do this to become an honorary member of the Hyena tribe, but is horrified by the idea. [[spoiler:Turns out [[ShownTheirWork her fears were justified]]; she then gets very, very ill.]]
** The hyena tribe also has an inversion of this in one of their [[JustSoStory origin stories]]. In hyena mythology, hares were originally carnivores and descended to herbivorism.
* ''Webcomic/KevinAndKell'':
** Sort of happened in when a dimensional traveler who was "furrified" into a rabbit on arrival maintained her omnivorous diet. This caused some shock to the local herbivores when she killed and ate a panther that attacked her.
** And of course, Coney the KillerRabbit, justified as she's [[InterspeciesRomance half-wolf]].
** Inverted by Bruno, a wolf who turns herbivore and even has a suitable digestive tract surgically installed. He also later gets herbivore teeth implanted after a fight with Rudy costs him his carnivore teeth.
* In ''Webcomic/DanAndMabsFurryAdventures'', the Demons Kira and Lorenda Soulstealer are voracious cannibals who eat countless other Beings -- at least, [[EarlyInstallmentWeirdness in the early days of the series]]. They also happen to be an anthropomorphic zebra and a ''cow'' respectively.
* In ''Webcomic/SluggyFreelance'', the cast always makes sure Bun-Bun doesn't get hungry, fearing he might say "What the hell, let's give meat a try."
* In ''Webcomic/SandraAndWoo'', Sid encounters Ruth, a squirrel who wasn't happy with her place on the food chain. She acquired a gun and only eats apex predators.
* ''Webcomic/{{Freefall}}'' has a truly surreal example: Dvorak's ''waffle irons''. He programmed them to recharge when their batteries ran low; he never specified ''how''.
* ''Webcomic/TheKennyChronicles'': Lagomorph Fuego accidentally eats Kenny's meat pizza, but his interior is mostly human guts so it's all good. Then he gains an addiction to meat in general.

[[folder:Web Original]]
* [[http://shirt.woot.com/friends.aspx?k=8143 This shirt]] and the accompanying description is not about retribution or turnabout, but is worth noting.

[[folder:Western Animation]]
* ''WesternAnimation/TheSimpsons'':
** In "Helter Shelter," the retirement home residents are watching a nature show about elderly animals. An elderly lion runs out of energy, whereupon the zebra turns around and takes a bite out of it.
** ''The Simpsons'' also sometimes portray koalas as savage carnivores, often gnawing on bones during panning shots of a zoo.
** Same can go for Elephants, in which they've been depicted as grabbing people to eat them whole. One exception being Stampy, who only puts them in his mouth.
--->"Now I've had my head in an elephant, a hippo, and a giant sloth."
** In an educational film Troy [=McClure=] tells LittleJimmy about the food chain. "If a cow ever got the chance he'd would eat you and everyone you care about!"
** In "The Scorpion's Tale", a shark consumes a tube of chemicals that turns an animal docile making it harmless. This causes a school of herring it was chasing to swarm up on it and devour it like hungry piranhas, leaving it nothing but cartilage.
** One "Treehouse of Horror" segment, "Burger Squared", had Krusty Burger feeding Grade A ground beef to cows and then making burgers from those cows. They turned people into zombies.
* A throw away joke in WesternAnimation/{{Futurama}} included a fast food vendor at a ball park announcing that his horse meat (cows are apparently extinct) comes from horses that are "100% horse-fed for that double-horse juiced-in goodness!"
* A ''WesternAnimation/LooneyTunes'' short in which Sylvester and Tweety are SnowedIn featured a mouse who hasn't eaten in so long he "forgot what food looks like." He takes one look at Sylvester and decides to have him for dinner. The same plot was reused later in a ''[[WesternAnimation/ThePinkPanther Pink Panther]]'' short.
* An unusual human variation occured in ''WesternAnimation/MrMeaty'' in which a group of soy-centric vegetarians were supposed to [[ImAHumanitarian eat their new employee]], as part of a plan that even they didn't really understand due to their extremely confusing "circle of life" chart that made no sense what so ever.
* The MickeyMouse [[WesternAnimation/ClassicDisneyShorts short]] "The Worm Turns" is actually about Mickey Mouse inventing a spritzer that can cause prey animals to turn against their respective predators: A fly attacks a spider, [[FurryConfusion a mouse]] attacks a cat, a cat attacks Pluto, and finally Pluto attacks Pete the dogcatcher.
* In the ''WesternAnimation/FamilyGuy'' episode "Road to the North Pole", Santa's reindeer had started eating elves and tore apart any elf that wandered near them.
* Sort of. ''WesternAnimation/MyLittlePonyFriendshipIsMagic'' mostly averts this with the ponies eating things like daffodil sandwiches, but they also eat eggs and honey, and drink milk, all of which are animal products. This goes a bit beyond the usual diet of real horses, but they are certainly not carnivores. [[note]][[FridgeHorror Thinking about it hard enough]], there are two exceptions: "[[Recap/MyLittlePonyFriendshipIsMagicS2E16ReadItAndWeep Read It and Weep]]" has gelatin as hospital food; gelatin partially comes from animal bones. "[[Recap/MyLittlePonyFriendshipIsMagicS1E13FallWeatherFriends Fall Weather Friends]]" has Pinkie Pie announce that she likes hot dogs, although later episodes establish that hot dogs in Equestria are grilled carrots in buns. [[/note]] "Magical Mystery Cure" plays this as a joke when Rainbow Dash tries to take care of Fluttershy's animals: she does such an awful job that the animals (who are primarily herbivores such as squirrels, rabbits, and chickens) end up rebelling and putting her in a pot to cook her.
* ''WesternAnimation/{{Kaeloo}}'':
** In the episode "Let's Play Trap-Trap", Quack Quack gets hungry after not eating any [[GRatedDrug yogurt]] for one hour. He then tries to eat Stumpy and Kaeloo.
** In Episode 61, [[BigEater Stumpy]] (who is a squirrel) and Kaeloo (a frog) get stranded on an island together. Before long, Stumpy attempts to cannibalize Kaeloo. Also, in the English dub, Stumpy's TrademarkFavoriteFood is changed from paninis to hot dogs.
** Eugly the rabbit eats sheep.
* In the Terrytoons cartoon "Silly Sidney", the eponymous Sidney (an elephant) tires of eating vegetable material, and asks a lion how to turn carnivore; he balks at the work involved in chasing down prey.
* In ''WesternAnimation/LlamaLlama'', despite the cast mainly consisting of herbivorous animals like llamas, sheep, goats, and giraffes, the characters often mention eating meat products like fish casserole and sausage.

[[folder:Real Life]]
* Most primates are primarily frugivorous, and it was a pretty convenient way of obtaining glucose in a jungle where sweet fruits are everywhere. Many primates have anatomical specializations that allow them to eat fruit, leaves, gum or insects. However, several species have developed a taste for meat as well, becoming outright omnivores, including Tarsiers (have ascended to obligate carnivory as they eat only insects, crustaceans, small vertebrates, and snakes), capuchin monkeys, baboons, chimpanzees, and humans. Chimpanzees and (especially) humans are two species noted for accelerated brain development, forcing opportunistic all-consuming omnivory because herbivorous adaptations (multiple rumination stomachs as in cows, or large appendixes and nutrient-absorbing colons as in gorillas) are slow and inefficient to supply it.
* The Inuit are the closest humans have come to being completely carnivorous, due to living in harsh Arctic tundras with little to no edible plants year round. They accomplish this by eating the entire animal, eating the meat raw or frozen (retaining heat-perishable nutrients like Vitamin C, and even the carbohydrate glycogen) and consuming huge quantities of fat to prevent protein poisoning.
* Red deer are in the ''Guiness Book of World Records'' as "Most Bloodthirsty Ungulate." It actively devours birds, small mammals, and even other deer. Cameras set up near bait left for wolves and coyotes show that more often than not, the deer are the first ones to show up and pick everything clean. They've also been known to eat the heads (just the heads) off of birds if calcium deprived. Suddenly, their name seems to be ''very'' [[MeaningfulName appropriate]]...
** However, even that ignores pigs, which are the only even-toed ungulates to have kept their ancestral omnivory, instead of turning into herbivory like camels or ruminants. Cetaceans, on the other hand, went from riverside small ungulate omnivores to a fully predatory group that also doesn't have much in the area of hooves. Or hindlimbs.
* Many herbivorous animals aren't above nibbling on sources of meat if it's available. Cattle have been documented devouring chickens for the iron in blood, and hippos will scavenge on the carcasses of other animals (their own species included). As meat is easier to digest than leaves, even an animal ill-equipped to ''hunt'' prey is unlikely to pass up fresh protein that's just lying there.
* Here are some otherwise strictly herbivorous animals that have nibbled on sources of meat if it's available:
** Cattle
** Hares and pikas
** Hippos (see above)
** Manatees
** Elephants (see below)
** Horses and mules
** ''Even'' Galapagos tortoises (see below)
* A [[http://www.huffingtonpost.com/2011/02/18/maneating-elephant-featur_n_825345.html rogue Asian elephant had killed 17 people in India]]. Once it was killed, [=DNA=] tests on the contents of its stomach revealed that it had [[ToServeMan consumed human flesh]].
* Some industrial producers of meat feed meat animals... well... meat. Usually they are "animal byproducts" that people wouldn't eat if you paid them. Unfortunately, the inclusion of cow neural tissue in cow-feed is responsible for Bovine Spongiform Encephelopathy (BSE), AKA ''Mad Cow Disease''. This is why [[WhyWeCantHaveNiceThings we can't eat cow brains]], which were traditionally consumed (and considered delicious) by many cultures (and not just ones noted for liking offal--the Midwest's fried-brain sandwich ''used'' to be made out of cow cortex).
* In evolution, animals have switched from herbivore to carnivore countless times. For example, some species of ornithischian dinosaurs probably included some meat in their diet, like the pachycephalosaurs and heterodontosaurs. There's even a new theory that freaking ''Triceratops'' ate some meat from time to time. Yikes.
* Regardless of diet, most placental mammal mothers eat the afterbirth after bearing young, to reclaim valuable protein and minerals their bodies will need to sustain nutrient-costly lactation.
* [[http://www.youtube.com/watch?v=t3NOhQlPGAU In this video]] a cow actively pursues and devours a live baby chick.
* Two videos of a [[http://www.youtube.com/watch?v=sQOQdBLHrLk deer]] and a [[http://www.youtube.com/watch?v=immd3tpqcOQ horse]], chasing and eating respectively one and ''three'' baby birds.
* [[http://en.wikipedia.org/wiki/Duiker Duikers]].
* According to a recent study, ''Galapagos Tortoises'' (yes, the beloved and humble GentleGiant of reptiles) will take advantage of their relationship with Galapagos finches and eat them for protein. To do this, they rise and extend their limbs so that the finch could look for parasites to feed on, only to be crushed to death when the tortoise withdraws its limbs.
* Dinosaurs arose from omnivore ancestors, with adaptations for either herbivory or hypercarnivory arising later; small animals like [[http://scotthartman.deviantart.com/art/Dawn-Thief-281226156 Eoraptor]] gave rise to both theropods like Tyrannosaurus and sauropods like Apatosaurus.
** A special mention is due to [[RaptorAttack dromaeosaurids]], hypercarnivorous animals belonging to the mostly omnivorous (and with plenty of herbivorous members) maniraptorans, themselves descended from hypercarnivorous theropods.
* Herbivory didn't appear in vertebrates until large reptiles and synapsids started to take said niche, some 300 million years after the first vertebrates appeared.
* Plenty of herbivorous invertebrate taxa have a few meat-eating species among them, like carnivorous caterpillars or predatory snails. Still others eat plants for their staple diet, but (as with locusts) start chowing down on their fellow bugs without hesitation when leaves get scarce and/or they're overcrowded.
* Even the humble sea sponge gets in on this. Most filter feed on whatever microscopic food particles float their way. Some, such as the genus ''Chondrocladia'', capture and feed on small crustaceans.
* Humans who adopt an all-meat or near all-meat diet often claim to feel stronger and more energized. However, they eventually run into the same problems as others who eat a similarly-restricted diet, like vegans. In this case, meat naturally contains very little fiber, so constipation may be an issue.
* Some horses have been known to eat meat--including grisly [[http://www.horsetalk.co.nz/2012/04/17/horses-as-meat-eating-killers/ insane man-eating killers]].
* A deer has been photographed scavenging from [[http://news.nationalgeographic.com/2017/05/deer-eating-human-forensics-decomposition/ a human corpse.]]
* A recent study of a hadrosaur coprolite revealed that it contained the remains of a crustacean (presumably either a crab or crayfish) inside of it.