Taxonomic Term Confusion

Charizard: Okay, so apparently I'm not a dragon. Well let me ask you this. What do I look like?
Blastoise: A lizard. You are a lizard with wings.
Charizard: You just described a dragon.
Blastoise: Just because you look like a lizard with wings doesn't mean you're a dragon. My cousin is a dragon and he doesn't even have wings.

— ''Poke Buds: Ep 1 Blastoise and Charizard FIGHT!''

Taxonomy, the classification of living things, is really complicated. For example, anyone who's worked in a record store and had to fit every band into one neat little category or other has an idea as to why: Many organisms defy traditional or obvious categories in the absence of genetic studies. This is why there is such a wide variety of terms for organizing living things (and theoreticians regularly come up with new ones).

Writers of fiction tend to tidy things up a bit. They regularly come up with creative ways of employing normal classification terms in ways that are incredibly inappropriate. Primarily, what seems to be at fault is a failure to recognize that the terms for taxonomic categories have specific meanings, and are not just interchangeable synonyms for "a big group of similar things". Sometimes they do know better; it's just that they couldn't resist the Beast Fable pun of having an Animal Kingdom. You know, where the lion is the King.

For the record, any group of related organisms, regardless of the degree of relatedness, is called a taxon. The major recognized taxonomic ranks are:

• Domain
• Kingdom
• Phylum
• Class
• Order
• Family
• Genus
• Species

(If you're having trouble remembering, remember this simple mnemonic: "Danny Kaye, Please Come Over For Good Strawberries" or, if you prefer, "Dear King Phillip Came Over For Good Soup". A commonly-used one is "Dumb Kids Playing Catch On Freeways Get Squashed". Before "Domain" was added to the top of the list, mnemonics were "Kings Play Cards Only For Gold and Silver," "Kings Play Chess on Fine Glass Surfaces," and "King Philip Came Over From Greece Swimming."^note Or if you're less mature, "Ken, Please Come Over For Gay Sex.")

Every species past and present is part of all of these, in a nested pattern. So a given kingdom will contain one or more phyla, which each contain one or more classes, etc. Although some phenomena (like horizontal gene transfer and hybridization) muddy this a bit, in general there is no overlap. In a way, as huge and diverse as life is, it can be easier to classify than records. (A band can create a hard-to-sort genre like "folktronica", but fish and birds can't have babies or otherwise be combined to make a new taxon — yet.) The demarcations just aren't as obvious, in part thanks to the granularity (as if every band was accompanied by hundreds of extremely similar bands, and the music itself was the only source material for data).

Compound variations on these terms such as "subspecies" and "superfamily" are in common use. Some taxonomists also make use of the term "tribe" for a rank intermediate between subfamily and genus. This is not just limited to fiction; in a strictly factual sense birds are technically reptiles, and the whole animal/plant/fungus distinction is being rewritten of late so more often than not, it's hard to know the correct terminology because it's always changing. It doesn't help matters that the current system was invented before evolution was understood, and that the ranks are pretty arbitrary. One "genus" might be older and more diverse than another "family." Some scientists even want to abolish taxonomic ranks.

Another important distinction is whether a named group is monophyletic ("one tree") or not. A monophyletic group is exactly all descendants of some ancestor species. One way to think of phylogenetics and cladistics is they are the determination of which groups are monophyletic. All groups with a taxonomic rank (e.g. a genus) should be monophyletic^note hence these groupings are constantly under revision as new evidence about monophyly is discovered, but commonly used group names may not be — e.g. "monkey" is not monophyletic unless you consider humans and other apes to also be monkeys, as Old World monkeys are more closely related to apes than New World monkeys are. How to deal with this is debatable, and indeed debated in the examples on this very page. Some would argue that "monkey" must include humans, others that "monkeys" are not a legitimate group, others that "monkey" is useful and legitimate, but you just need to be aware it is not monophyletic.

The scientific Latin name for a species consists of the genus name (capitalized), followed by the species name (in all lower case), both italicised. Tyrannosaurus rex is genus Tyrannosaurus, species rex; Homo sapiens is genus Homo, species sapiens. If the species is well known, or has already been mentioned earlier in the same work, the genus name will frequently be abbreviated to a single letter, e.g. T. rex or H. sapiens. If more hairsplitting is needed, the subspecies or variety name can be appended as a third word, e.g. Homo sapiens sapiens.

Frankly, it's not surprising that writers are sometimes ignorant or confused. Though this can also turn into a case of Fan Wank as many of these words also have different less precise meanings in regular English as in family and class are both used to refer to groups of similar things, a class of ships, the t-series family of trucks so a lot of these errors are just people using the words with their regular meanings. But there's really no excuse for such errors when they're committed by scientists who work in zoology and other fields that explicitly require them to be well-versed in how the nomenclature works.

A nearly omnipresent issue in science fiction, which tends to crop up in fantasy as well, concerns capitalization of species names. In real life, species names are never capitalized (see "human", "cat", "eagle", "codfish", "oak", etc.). Nationalities and cultural groups, however, are always capitalized (see "American", "Russian", "Chinese", and so on). In fiction, where alien planets tend to be portrayed as just foreign countries but a bit further away, alien species and fantasy races tend to be treated as essentially just exotic nationalities and duly capitalized, often being listed alongside noncapitalized instances of "human" without a trace of irony. Some works aim for consistency by also capitalizing "Human", but they're typically in the minority.

Hidden object casual games regularly succumb to this trope, as when clicking on a "seahorse" isn't registered as finding a "fish".

Of course, things are also more complicated than even this. Cladistics, dendrograms, phylogenetics... We'll just leave it at this lest Your Head Asplode. For entirely imaginary taxanomics Played for Laughs, see Binomium ridiculus. Compare Improbable Taxonomy Skills, the ability to fully classify an organism with just a cursory examination.

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Examples:

Card Games

• The Ed-U-Cards game "Animal Bird or Fish" correctly includes a seahorse in the "fish" category—but also includes a dolphin (mammal) and a frog (amphibian).

Comic Books

• In a particularly head-hurting example, MUTO Prime in the Monsterverse comic Godzilla: Aftershock is described as simultaneously evolving from the MUTOs, yet at the same time is the same species which created the MUTOs in the first place. Not only is this a complete violation of how evolution and speciation works, but would be impossible to render in modern cladistics, as it implies that the evolution of the MUTOs and Prime is nothing more than a tightly-closed loop. Somewhere, a taxonomist is probably crying.
• Sonic the Hedgehog (Archie Comics): The Funny Animal characters are considered one species called "Mobian" despite being Uplifted Animal versions of various animals, ranging from hedgehogs to crocodiles.
• Star Wars (Marvel 1977): Subverted in a comic in which Jaxxon, a rabbit character, says "I ain't no rodent!" He's an alien Beast Man, so he's hardly a rabbit either.
• X-Men: The mutants are referred to as a species separate from humans, called Homo superior, even though they can produce fertile offspring with humans. It would be more accurate to call them a new subspecies ("subspecies" being a fairly arbitrary and flexible term). This is partially solved in later comics where Magneto, and several others, refer to Mutants as "Homo sapiens superior" (compared to Homo sapiens sapiens). Although some writers forget this, Homo sapiens superior specifically refers to a human subspecies with a single, quantifiable characteristic that Homo sapiens sapiens lacks — the emission of a certain type of brainwave (this is how Cerebro distinguishes mutants from baseline humans). Superhuman powers or anatomical quirks are very common among mutants, but they are not a requirement.^{About "mutant"}Just about every organism that has lived has mutations somewhere in its genome, compared to its parents, making them "mutants" by the strict definition of the term, so it's not a scientifically useful term anyway.

Comic Strips

• An In-Universe example occurs in one Calvin and Hobbes storyline, where Calvin is writing a report on bats, which he claims are bugs. Everyone points out that he's wrong, but he refuses to listen.
  Calvin (angrily): Who's giving the report, you chowderheads or me?

Films — Animated

• Disney Animated Canon:
  • The Sword in the Stone: During Merlin and Mad Madame Mim's Wizard Duel, the two spellcasters are only allowed to turn into animals, and not vegetables, minerals, or "nonexistent creatures like pink dragons and such." However, when the duel is over, Mim breaks one of her own rules by turning into a dragon (specifically a purple dragon), and Merlin defeats her by turning into a germ, which is not even an animal at all!
  • Zootopia: At a few points, characters refer to the "predator family". Even going by the in-universe definition of "predator" (that is, a sapient mammal species that used to eat other sapient mammals), that's still wildly biologically inaccurate (one could say that they were thinking of Carnivora, but that's an order, it contains several types of animals that don't eat mammals (and some don't even normally eat animals, period), and there are mammals outside of Carnivora that eat other mammals).
• Finding Nemo: The "species" listed in Mr. Ray's educational song are actually phyla.

Films — Live-Action

• Batman Forever: Dr. Meridian describes bats as "flying rodents", a mistake that Batman corrects.
  Dr. Chase Meridian: Well, let's just say that I could write a hell of a paper on a grown man who dresses like a flying rodent.
  Batman: Bats aren't rodents, Dr. Meridian.
• The Faculty contains this line: "We discovered a new phylum in biology class today; maybe even a new species." This makes no sense, because something in a new phylum would have to be in a new species. Probably the actor accidentally switched "species" and "phylum" around from the scripted line, and nobody caught the mistake.
• Godzilla: King of the Monsters (2019): Titans are all classified under the genus Titanus. Titans represent everything from Godzilla (a reptile) to King Kong (a mammal) to Scylla (a mollusc) to Mothra (an insect). While this is already bad enough, what tips this into making taxonomists everywhere cry themselves to sleep are the following, particularly egregious missteps:
  • As a genus name, Titanus couldn't be used to represent the Titans, as there is already an organism which uses the name, the Titan beetle (Titanus giganteus).
  • Assuming the different Titans do belong to different phyla and classes in the animal kingdom, they would not be able to share the same genus.
  • King Ghidorah is also classed as a titan, even though it's heavily implied in the film that he didn't come from Earth. If this is true, it would be impossible to classify him under the current taxonomic system at all, as by virtue of all life discovered thus far being native to Earth, King Ghidorah's presence would require starting completely from scratch to account for space-faring creatures as well.
• In Guardians of the Galaxy (2014), calling Rocket a "rodent" is one of his Berserk Buttons. He's a raccoon, order Carnivora; rodents are order Rodentia.
• In The Horror of Party Beach, a doctor explains that the monster is actually a dead human whose organs were invaded by aquatic plants before they had the chance to decompose, and calls the result "a giant protozoa." Protozoa are single-celled lifeforms, being neither plants nor animals. "Protozoan" is the word for describing one in the singular.
• Jurassic Park:
  • Alan Grant says that humans and dinosaurs are "two species separated by sixty-five million years." Granted, that line probably sounded great in the trailers, but you'd think a paleontologist would know better than to call dinosaurs a species.
  • More generally, the Jurassic Park series often uses "species" when it means "genus", such as in the first film when Grant is handling a newborn baby dinosaur and asks what species it is, to which Wu answers with Velociraptor, its genus name.
• Kill Bill: Not all members of the Deadly Viper Assassination Squad are actually named for vipers. Cottonmouth (O-Ren), Copperhead (Vernita), and Sidewinder (Budd) are vipers, but Black Mamba (the Bride herself) and California Mountain Snake (Elle) aren't.
• Kong: Skull Island: Supplementary material released for the film claims that the Leafwings, a species of seemingly reptilian flyers, are a 'subspecies' of the Psychovulture, a monster with considerably different physiology. This would be a stretch, but still possible, but what really throws the taxonomy out the window is the way they're classified, and improperly capitalised, to boot! The Leafwings are Icarus Folium (which also clashed with the binomial name chosen for the also-existing Spirit Tiger at the time, Icarus Tigris), while the Psychovultures are Vultura Insanus. Not only would this not make the Leafwing a subspecies of the Psychovulture, but under this arrangement, it would belong to an entirely different genus and species.

Literature

• The Book Of College Pranks: In relating a story about how a cow was elected Homecoming Queen because all the human entrants were disqualified, it says that the cow "was in the wrong phylum, but at least had not cheated." In fact, cows and humans are in the same phylum (Chordata) and the same class (Mammalia).
• Bored of the Rings has an appearance by "six different phyla of giant insects". Insects, whatever their size, are a single CLASS of phylum Arthropoda.
• Childcraft: About Animals identifies arthropods as a "class" of animals, when it really is a phylum. It could be argued that phylum is too advanced a word for a book aimed at 6-year-olds, but that could also be argued of arthropod, and that didn't stop the publishers. (Probably they figured that anything was better than risking spiders getting classed as "insects".) Even more egregious as there are more arthropods in existence than every other phylum of animals combined.
• Discworld:
  • In Hogfather, Ponder Stibbons states that bananas are actually a kind of fish in a deliberately exaggerated in-universe example.
  • In-universe example: Many people in Ankh-Morpork used to be confused about the difference between apes and monkeys. Since this is the Berserk Button of the Unseen University Librarian, an orang-utan, they have since learned that the main difference is that a monkey can't hold you by your ankles and bang your head on the floor.
  • In-universe, in The Wee Free Men, toddler Wentworth calls the whale "Big fishy", and Tiffany immediately corrects him, and explains what a mammal is. A slightly confused Wentworth tries "Big water cow", which she accepts.
• Dracopedia: The series' use of taxonomic terms is rather messy. Primarily, it confuses genuses and families and assigns binomial names to both individual species and individual genuses/families.
  • Firstly, the books sort dragons into broad groups, such as amphipteres, great dragons, hydras and so on, that it calls "families", and then within each family describes specific types that it calls "species". In taxonomy, a "family" is rank used to group together genuses; genuses, in turn, group together species. However, all species within each of the book's families share the first part of their binomial names, which in biology identifies the genus — all amphipteres are Amphipterus [something], all great dragons are Dracorex [something], and so on. Most real families consist of separate genuses^note for example, the real-life family Hominidae includes the genuses Homo, Pan, Gorilla and Pongo, respectively humans, chimps, gorillas and orangutans. Some families do only include a single genus, but this is typically the exception and it stretches credibility that every individual family in the book would be a single-genus one.
  • Secondly, each family/genus is given an italicized, binomial name in the form of Draco [name], and each individual species within it is then [Name] [other name]. For instance, the great dragon "family" as a whole is referred to as Draco dracorexus, while the Welsh red, a specific species of great dragon, is Dracorexus idraigoxus. In real taxonomies, families do not receive binomial names — family names are not italicized, end in -idae^note animal families, at least; plant, algae and fungus families end in -aceae and are not included in the names of the genuses and species within them. Anything above the genus level would just be referred to as "[species x], in family y, in order z, etc." Assuming that the great dragon family does happen to include a single genus, correct nomenclature would be to call it something like Dracorexidae and then name its individual species Dracorex [species name].
• Humanx Commonwealth: In Cachalot, a marine biologist refers to a newly-discovered undersea race as "the first intelligent invertebrates we've ever encountered". Granted, this wouldn't be an issue in some scifi series... but in the novels, humans and thranx have been virtually joined at the hip for centuries. Did Alan Dean Foster forget that his insect-based thranx also lack an internal skeleton?
• InCryptid includes a field guide to many cryptid species on the author's website, but sometimes bends the rules of taxonomy (rather egregiously, since Seanan McGuire was a herpetologist before becoming a novelist).
  • The entry on Lindworms calls them "a member of the largest surviving subfamily of non-saurian giant reptiles". While the skink family is indeed the most diverse family of lizards, "saurian" can refer to "all extant reptiles (and their extinct relatives) except turtles" or simply "lizards" (that's what it means in Greek). While she may have been using "saurian" to mean dinosaurian, most lizards would not be considered "giant reptiles".
  • Many entries have a "family" name that does not end in the customary "-idae" suffix (though in most cases these were made up In-Universe by cryptozoologists without the knowledge or approval of the ICZN).
• Moby-Dick: Herman Melville spends a chapter committing an extended crime against taxonomy. He starts by classifying whales as "spouting fish" and proceeds from there.
  • Melville notably shows his work otherwise, enumerating physiological differences between whales and "other fish", and even refers to the Systema Naturae by Carl Linnaeus, and Ishmael's^note who is a former country schoolmaster subsequent "classification" can be read more as Take That! from a more down-to-earth (or rather down-to-sea) point of view of working class protagonists of the novel, using word "fish" in a looser sense of "any exclusively marine vertebrate" rather than as "a strictly defined taxon".
    "I submitted all this to my friends Simeon Macey and Charley Coffin, of Nantucket, both messmates of mine in a certain voyage, and they united in the opinion that the reasons set forth were altogether insufficient. Charley profanely hinted they were humbug."
  • Ishmael's actual taxonomic "system" consists of simply grouping of cetaceans roughly according to their respective sizes (and thus their economic value), with terminology based upon book sizes — that is, Folio, Octavo and Duodecimo. The best acceptable explanation for all this is just regarding chapter 32 "Cetology" as a prolonged Stealth Parody of both the common whalers' sea-lore and then-current scientific cetological classification.
• Spellsinger refers to shrews (order Eulipotyphla) as "rodents" (order Rodentia).

Live-Action TV

In General:

• Food Network: Occasionally, a host will try to emulate Alton Brown's use of scientific terminology and wind up sounding like a Know-Nothing Know-It-All. The host of Food Feuds, for one, has openly referred to clams as crustaceans, apparently on the assumption that all seafood without fins is in the same taxon. Adam Growe made a similar mistake on the Canadian edition of Cash Cab.

Series:

• In Bones, for Valentine's Day, Hodgins splices rose DNA into a slime mold, creating a sweet-smelling variety he claims will be called Angelicus montenegro. Just adding a bit of extra DNA doesn't change its genus or species, nor does it qualify as a "hybrid" as Hodgins claims. A true hybrid of two species would be called "[Species 1's name] x [Species 2's name]"; at best, Hodgins can add Angela's name to his creation's strain, not its species.
• Doctor Who has a species of reptilian humanoids, the Silurians, that are referred to sometimes as Homo reptilia. The Homo genus is mammalian. Furthermore, reptiles (or any tetrapod, for that matter) hadn't even evolved by the Silurian period, making that part of the name rather baffling as well. (The Doctor once suggested that they should have been called "Eocenes" after another geological period they didn't come from.)
• Elementary: In "Dead Clade Walking", Holmes incorrectly says a "clade" is any group of organisms that have survived a major extinction event, which is somewhat closer to the definition of the "dead clade walking" (strictly speaking, that refers to a clade that's functionally extinct and probably doomed but which still has a few specimens hanging around). A clade is simply any named group consisting of an ancestral species and it descendants.
• Fringe: The episode "Bound" features what looks like a cucumber-sized slug that crawls out of its victim's mouth, which the cast later identifies as an enlarged single-cell cold virus (which don't have cells, even a single one).
• Jessie: In-universe example: Mr/s. Kipling the water monitor is called a dinosaur (namely a Velociraptor) as an insult. Another episode goes with the "koala bear" term (although Ravi notes that koalas are marsupials).
• Monsterquest: The narrator seems to have confused "species" with individuals, inverting the usual pattern where higher-than-species clades are mixed up. The voiceover claims that "millions of species" of fishes are found off the coast of Florida, which is a couple of orders of magnitude more than the actual number of fish species on the planet (~32 thousand).
• Star Trek :
  • The franchise seems to have repurposed "Homo" to mean "intelligent humanoid". Vulcans are Homo vulcan, for instance, despite the fact that as aliens they would have no biological relationship to any Earth life.
  • Star Trek: Discovery: Burnham once refers to the tardigrade "species" as if there's only one. Tardigrada is actually a phylum with over 1,150 species. As a scientist, she should really know better.
• Surface: The female scientist near the beginning of the series described the creature she'd seen as "an entirely new phylum of mammal!" This is especially mind-boggling when we later learn that the creatures are created from the DNA of Liopleurodon (a prehistoric sea reptile)... which she describes as "a type of prehistoric eel"... you know, just stop trying. If they just wanted to incorrectly refer to something as a "prehistoric eel", they could have at least used a mosasaur, which are far more eel-like in shape than pliosaurs such as Liopleurodon, which were generally shaped more like sea turtles with crocodile heads.

Tabletop Games

• Dungeons & Dragons: Meta example: the Wizards of the Coast forums for 3.5 had a lot of fun early on trying to determine the exact taxonomic classification of dragons, due to a mention in the Draconimicon that despite their reptilian appearance, dragons are actually endothermic mammals.

Video Games

• Mass Effect: Zig-zagged. The names of the various alien species are very carefully non-capitalised and aliens are referred to as "mammal-analogues" or the like when it's needed, rather than making the mistake of simply calling them "mammals," but they still refer to aliens as animals and plants and bacteria and insects without the "-analogue" modifier.
• Pikmin:
  • Iridescent Flint Beetles, Iridescent Glint Beetles and Doodlebugs are considered part of three distinct families, respectively the flint beetles, glint beetles and flint bugs. Despite this, they're also referred to as members of the same genus, Pilli (P. envelopens, P. auricus and P. flatularum, respectively). Taxonomically, this doesn't make any sense — species are group into genuses and genuses into families, which means that all members of a genus must be part of the same family. Notably, however, the Japanese dub describes the Iridescent Flint Beetle and Doodlebug as being part of the same family.
  • The games classify Unmarked, White, Yellow and Electric Spectralids are part of the Fenestari genus, while Red Spectralids are classified as Fenestrati. However, they're split into multiple families that don't follow genus lines — Unmarked Spectralids are part of the flitterbie family, the ones from the third game are part of the flutterbie family, and Electric Spectralids are part of the floaterbie family (although the Japanese dubs consider the last two a single group). This is a more extreme version of the beetle example, as besides just splitting one genus across three families this system lumps in some of its species with a member of an entirely different genus — which, obviously, isn't something that can happen in real life.
• Parkasaurus:
  • The seven major groups of dinosaurs are called "families", even though they're not. The Sea Monsters DLC adds two more "families" — aquatic and semi-aquatic — which are more like broad descriptions.
  • The animals are collectively referred to as "dinosaurs". While this makes sense in the base game, the Sea Monsters DLC includes nothosaurs, plesiosaurs, ichthyosaurs, crocodilians, turtles, and fish.
• Sonic the Hedgehog is often erroneously referred to as a rodent. Hedgehogs actually belong to the order Eulipotyphla, which indeed contains several other animals frequently mistaken for rodents (namely moles and shrews). Hedgehogs and rodents are boreoeutherian mammals, and that's where they diverge: Eulipotyphla is in superorder Laurasiatheria (which contains animals like ungulates and bats), while Rodentia is in superorder Euarchontoglires (which contains animals like rabbits and primates).
• StarCraft II: Averted. While the previous game (and early Expanded Universe materials) capitalize species names as is often done in science fiction, StarCraft II promotional materials and the new books all spell "protoss" and "zerg" with non-capitals. The fandom hasn't quite caught on yet.
• In Sticky Business, Bernd S. asks you to make rodent stickers such as rats, rabbits, and capybaras. Rabbits are actually lagomorphs, but are commonly mistaken for rodents.
• StreetPass Mii Plaza: In Flower Town/StreetPass Garden, the plants are classified as being different "breeds"; pollination methods aside, different varieties of a given plant species are referred to as cultivars, and cross-species hybrids are called... er, hybrids.
• Warcraft: The capitalized-nonhuman-species-names variant is notable averted, as across all media species names are almost always left uncapitalized. However, many, many fans do so anyway.

Web Original

• The Nostalgia Critic: The Critic admits in his third "F*** Up" countdown that in his earlier review of Dunston Checks In where he repeatedly calls the eponymous orangutan (and other films staring ape actors) monkeys, he didn't know there's a difference between apes and monkeys until he's corrected by his watchers. However, per modern cladistics, the correction is the erroneous one — "monkeys" include all higher primates that aren't lemurs or other prosimians, and apes are indeed a specific group of monkeys in the same sense that humans are a type of ape, monkeys a type of primates and primates a type of mammals.
• RWBY: Little Bit Beastly characters called "Faunus" are implied to be one species separate from humans. This includes reptile Faunus, fish Faunus, and mammalian Faunus.
• An extremely stupid example: There was a video by a certain "Angry MGTOW" (now gone, but you can watch an, err, review by TL DR here) where he claims that women suck and even cockroaches are better. At one point he claims "animals tend to be more compassionate than the female species of our group!
• During a humorous argument between a Blastoise and a Charizard in ''Poke Buds: Ep 1 Blastoise and Charizard FIGHT!'' the later makes the claim that he is awesome because he is a dragon, which Blastoise refutes for being circular reasoning before pointing out that Charizard isn't a dragon at all, which leads to the following quote posted above for the page.
• Not Always Right: This customer claims chickens to be mammals.

Western Animation

• The Angry Beavers: One episode descries rabbits as rodents. Rabbits are lagomorphs, not rodents, though Rodentia and Lagomorpha are sister orders in the clade Glires.
• Dinosaucers, even if it's a show about intelligent dinosaurs, includes in the cast an ichthyosaur, a plesiosaur, a dimetrodon, and a pterosaur. None of the four are actually dinosaurs.
• Ed, Edd n Eddy: Done in-universe when the trio makes a bet by taking on each other's personality quirks and behaviors, with Eddy trying to unsuccessfully imitate Edd's Sesquipedalian Loquaciousness by claiming chickens to be mammals.
• Family Guy's Meg Griffin calling a raccoon a rodent. They're actually members of the order Carnivora, close relatives of BEARS. Rodents and carnivores are both boreoeutherian placental mammals, but that's about as far as their taxonomic relationship extends. It's like saying we humans (which are primates) are related to horses (which are perissodactyls). Life After People: The Series did the same thing.
• Futurama:
  • In "A Clockwork Origin", Darwinius massilae is presented as a transitional form between apes and humans, when in fact it is a lemur-like form that has little to do with humans. Also, a transitional form between apes and Darwinius is referred to as Homo farnsworth, but it would be far too primitive to be Homo if it went that far back.
  • Bender's Game: Done in-universe. When a character refers to an enormous spider he was riding as a "giant bug", the Professor angrily corrects him by calling it a "giant arachnid".
  • "Möbius Dick" makes a running gag out of Leela calling people out on the "whales are fish" thing. Though it's a rather arbitrary line to draw insisting that a fourth-dimensional, vacuum-inhaling, fractal-exhaling Space Whale was a mammal/whale, instead of an Animalistic Abomination.
• Jackie Chan Adventures had a weird one in which Jackie and a crime boss refer to an octopus as a fish and respectively are corrected by Captain Black and a random mook by saying it is a "multipod". What makes this a headscratcher is that the correction is more incorrect then the original statement because there is no taxon called multipod nor has one ever existed.
• The Legend of Tarzan: Done in-universe in an episode where, after capturing a magical white gorilla with Healing Hands, the villain goes on a rant on his Mooks because they repeatedly refer to it as a monkey.
• Looney Tunes:
  • Elmer Fudd class Bugs Bunny a rodent. Bugs himself, in "Gorilla My Dreams", claims his scientific name is Rodentus rabbitus. However, in the Elmer Fudd case at least, the mistake is perhaps forgivable. Indeed, taxon Lagomorpha was placed within Rodentia until at least the early 1900s, making then-Rodentia equivalent to now-Glires, and Fudd was already depicted as a middle-aged man in 1940.
  • Bugs is also frequently referred to as a hare, especially if it makes a good title-pun.
• Phineas and Ferb:
  • "What a Croc!" refers to crocodiles as lizards. Crocodilians are more closely related to dinosaurs and thus birds, and they are actually far away from lizards on the evolutionary tree.
  • "The Return of the Rogue Rabbit": Subverted and also done in-universe when characters would object to rabbits being called rodents and correct that they are lagomorphs.
  • An early episode "Toy to the World" had a platypus referred to as a marsupial. Later episodes corrected this and have platypodes properly identified as monotremes.
• The Simpsons:
  • "Lisa's Substitute": After Lisa calls Homer a baboon, her offended dad describes baboons as "the stupidest, ugliest, smelliest ape[s] of them all!" Of course, this being Homer, it would be very surprising if he got his terminology right.
  • In "Worst Episode Ever", there's a radioactive ape briefly mentioned in a police VHS Bart and Milhouse found in Comic Book Guy's illegal VHS stash. The ape appears on-screen in Flanders's car, and it's very clearly a baboon, which are not apes; baboons and apes are both members of parvorder Catarrhini, but that's as far as their biological relations stand.
• Spongebob Squarepants:
  • The show treats "plankton" as if it were a species the character named Plankton belong to. The term "plankton" is not actually taxonomic at all, it refers to any oceanic organism that floats but cannot swim against the current. Given the show often shows its work about marine biology, and that Plankton is actually a copepod, this was probably done for simplicity's sake.
  • Plankton has also been known to refer to himself as a "protozoan" or "single-cell", neither of which are descriptions that apply to copepods.

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