For example, mice are stereotyped as mischievous critters who are capable of being cute and lovable. Rats, due to being bigger and significantly less cuddly looking (even if in Real Life, cuddlier than mice), are rarely given as much leeway. Calling someone "mousey," though not exactly a compliment, lacks a harsh connotation, it just means they're quiet and easily startled; calling someone "ratty" or a "rat" implies they're dirty and disgusting. If the hero is a mouse, one of the villains or anti-heroes will be a rat. One way to insult a mouse is to "mistake" him for a rat.
Keep in mind that there is no Truth in Television here and the only reason this trope came to be were the many different perspectives of uneducated people who have yet to study all of these animals.
However, a work does not need have a direct face off to give off this vibe. Mistaking one animal for the other and having said animal correct you with distaste ("Oh heavens no, I'm not a toad, I'm a frog!") gives off the implication that one is somehow an inferior version of the other.
See I Am Not Weasel if being mistaken becomes a running gag (the mistake need not actually be considered offensive to the animal, just incredibly exasperating), Elves vs. Dwarves for a magical equivalent, Slobs vs. Snobs, which is often used to justify this Fantastic Racism, and Always Chaotic Evil if the animal's prejudices are justified. See also Nice Mice and You Dirty Rat!. This trope usually follows Animal Stereotypes.
The "pleasant" and "unpleasant" animals can either be related, similar, or both.
- Purposely invoked in Pokémon. The Chick of the season, May, catches a Wurmple. The Dark Chick, Jessie, also manages to catch a Wurmple. Now Wurmples can either evolve into a sweet looking little butterfly (Bug/Flying) or an obnoxiously colorful moth (Bug/Poison). Guess which girl gets which? This is a subversion though, as both Pokémon are actually quite bad, arguably the former being the worst. Dustox make messes when they eat, leaving trees barren whenever they swarm into an area and scatter noxious dust as a defense mechanism. Beautifly are actually quite savage despite their appearance, being very aggressive when provoked or disturbed and attacking by stabbing opponents with their proboscis to drain their "fluids". The anime does not, however, bring up Beautifly's more unpleasant traits, and largely plays this trope straight (although the extent of Dustox's villainy is its association with Team Rocket).
- The season 1 finale of Squid Girl introduces the octopus-like Kozue Tanabe, who is kind and gentle in contrast to the titular squid-like character.
- In Kirby: Right Back at Ya!, King Dedede would insult his snail associate Escargoon by calling him a slug.
- One of Spider-Man's recurring enemies is Mac Gargan a.k.a. the Scorpion.
- While all the good characters in The Great Mouse Detective are mice, the Big Bad, Professor Ratigan, is a rat. Just don't call him that to his face.
- The Lion King:
- Inverted with Pumbaa. He's a warthog, and being called a "pig" is his Berserk Button. Normally, you'd consider a warthog to be the unpleasant counterpart to a pig.
- The Lion King also depicts lions as noble, majestic and mostly good guys and hyenas as dirty, stupid and cowardly bad guys. Deconstructed in The Lion Guard, where hyenas turn out to be mostly good.
- In the Shrek movies Donkey wants very much to be a horse.
- In Finding Nemo, sharks can't stand dolphins because, according to them, they're show-offs (and liked by humans).
- In Shark Tale, dolphins appear to be one of the few animals that sharks don't mess with (basically their equals). When a "vegetarian" Shark decides to live amongst fish, he disguises himself as a dolphin (even though dolphins also eat fish).
- Averted in Ratatouille where rats get to be the heroes for once (though no mice appear), though considering the title is a play on words, it's rather necessary.
- Antz depicts ants and termites as mortal enemies. The ants are highly anthropomorphic (as are a few other insects), while the termites are The Horde. Ultimately, this is played with in that the termites are implicitly Non Malicious Monsters, while the actual villain is an ant general who needlessly provokes them to kill the soldiers not loyal to him.
- Played with in The Secret of NIMH. The heroine is a mouse, and Auntie Shrew thinks rats are brutes, but the rats of NIMH turn out to be benevolent, with the exception of Big Bad Jenner, although Brutus is still pretty menacing.
- The Good Dinosaur has Arlo and Spot helping a family of benevolent Tyrannosaurus rex retrieve their longhorn herd from a pack of villainous Velociraptors.
- In The Princess and the Frog, Dr. Facilier is commonly associated with rattlesnakes. As a contrast, Mama Odie is accompanied by a friendly snake who appears to be a non-venomous constrictor.
- A Bug's Life pairs heroic, hard-working ants with evil, bullying grasshoppers that steal the ants' food.
- In Pinocchio, Jiminy Cricket takes offense to Lampwick calling him a grasshopper.
- In the first Stuart Little movie, a bully of George's gets punched in the face when he states "You're right, he's [Stuart] not a stupid mouse, he's a stupid RAT."
- In Inglourious Basterds, Hans Landa muses on the differences and similarities between rats and squirrels.
- Planet of the Apes:
- Gorillas are ruthless while chimpanzees are sympathetic (which is ironic considering that in real life, gorillas are relatively calm, peaceful herbivores whereas chimpanzees are bad-tempered, often violent omnivores).
- In the Planet of the Apes (2001) one gorilla was very offended when Mark Wahlberg's character called him a monkey.
- Jurassic Park started the trend of raptors being the main "evil" dinosaur, while former dinosaur Big Bad Tyrannosaurus began to be put in a heroic light. Deconstructed in Jurassic World where raptors are portrayed more sympathetically albeit still dangerous, and eventually the last surviving member of the pack Blue teams up with T. rex Rexy in bringing down the Indominus rex.
- In The Lion, the Witch, and the Wardrobe, white tigers can be seen in the White Witch's army, contrasting with the good lions. Subverted in Prince Caspian where orange tigers are good.
- In The Bible goats represent evil people and sinners, whereas sheep represent good people and the faithful.
- In the Redwall series, mice are good whilst rats are evil, and otters and badgers are good while stoats, ferrets, weasels, martens and wolverines are evil.
- In Kim Newman's The Hound Of The Durbervilles, Professor Moriarty breeds wasps, this apparently being the evil equivalent of Sherlock Holmes becoming a beekeeper.
- In Garry Kilworth's House Of Tribes, the protagonists are all mice, while one of the antagonists is a mean dirty old murderous rat.
- In 20,000 Leagues Under the Sea, baleen whales vs cachalots (called sperm whales in modern times). Nemo is adamant against killing baleen whales for sport, but has no problem with killing cachalots — described as "cruel, mischievous creatures".
- In Discworld, calling the orangutan Librarian a "monkey" is an invitation to a painful lesson in Taxonomic Term Confusion, administered by red-furred arms strong enough to hold someone upside-down by the ankles and bounce their noggin on the floor.
- The Jungle Book:
- In Babar, the elephants are gentle and civilized, and live in a kingdom ruled by The Good King, whereas the rhinos are boisterous and violent, and led by a selfish dictator. The conflict between the two species is particularly played up in the Animated Adaptation by Nelvana.
- When Kermit the Frog is called a toad on The Muppet Show, he explains that "frogs are handsome, debonair and charming, while toads are ugly and give you warts."
- Done all the time in the Pokémon games: Caterpies vs Weedles, Pidgeys vs Spearows, Ledybas vs Spinaraks, and Skittys vs Glameows.
- Inverted in Jurassic Park: The Game. Troodon are even worse than the Velociraptor, to the point the latter flee when they sense the former's presence.
- Spyro 2: Ripto's Rage!: The enemy Breezebuilders in Zephyr are falcons and parrots, while the friendly Breezebuilders in Breeze Harbor are pelicans.
- Inverted in Kingdom Rush: Vengeance, the fourth game in the series where you play as Vez'nan's Dark Army to fight the forces of good. The Pleasant Animal Counterparts to the Wulves and Worgs are Watchdogs, and the counterparts to the Winter Wulves are Glacial Wolves (which are actually ice elementals).
- In the Plants vs. Zombies series, both the Plants and Zombies have spellcasters with Baleful Polymorph spells. The Wizard Zombie turns the good Plants into sheep, while Rose turns the evil Zombies into goats.
- Tiny Toon Adventures: Fleas are heroic and sympathetic while ticks are evil and one is the Big Bad and Corrupt Corporate Executive in "Flea for Your Life."
- Inverted in Ovide and the Gang. Cy Sly the python is the main villain, while his Egyptian cobra cousin is a good guy. Played straight with Polo vs. Cy; the lizard being one of the heroes in contrast with the snake.
- The Lion Guard:
- In "The Imaginary Okapi", Makucha the leopard is the villain of the episode, in stark contrast to heroic cheetah Fuli as well as the noble lions of the Pride Lands. Subverted later in "The Trouble with Galagos" where we meet the good leopard Badili (although the episode's antagonist is also a leopard).
- "Too Many Termites" is about the Guard mistaking some harmless aardwolves for the bad hyenas.
- "Ono's Idol" introduces good eagle Hadithi, a contrast to the evil vulture Mzingo. The opposition between the two raptors gets played up in "Fire from the Sky".
- The cobra (Ushari) is antagonistic, while pythons are good.
- Geckos, chameleons, and agamas are good, while villainous lizards have been skinks and a monitor lizard.
- Downplayed with baboons. While they are prone to be more antagonistic than other monkeys, they are mostly good.
- However, there has been instances where the show averts this. Particularly, rhinoceroses are just as good guys as the elephants and hippopotamuses, and gorillas are just as friendly than the chimpanzees and monkeys. Although this may be because the show seems to avoid making herbivores antagonists.
- The titular character of Kenny the Shark claims to have a dislike for dolphins due to them, according to him, being snobbish for their intelligence. The episode "Whalin' on Kenny" has him getting menaced by a ruthless orca.
- Inverted in Unikitty!, where Eagleator is the Evil Counterpart to Hawkodile. Normally, you'd expect a hawk and a crocodile to be the unpleasant counterparts to an eagle and an alligator.
- Kung Fu Panda: Legends of Awesomeness: The chosen snake villain is a cobra, in contrast to the heroic Viper (vipers are venomous like cobras, but look less "evil").
- The Regular Show episode "A Bunch of Full-Grown Geese" has a battle between heroic ducks and evil geese.
- The Arthur episode "Pets or Pests" has a sort of reversal of roles: a mouse serves as a pest for the Read household (albeit still non-antagonistic), while Ladonna's pet rat is very helpful and takes offense when mistaken for said mouse.