Reindeer Aren't Real

This is when someone, usually The Ditz or the Cloudcuckoolander, is ignorant, confused, or ill-informed enough to lump "things that are well known to be real" in with "things that are made up." This is often applied to ethnic groups, but can also include historical characters, countries and animals.

A Sister Trope to Global Ignorance. Tangentially related to Flat Earth Atheist.

If fantastic creatures don't believe in mundane ones, then that's Faeries Don't Believe in Humans, Either.

Anime and Manga

 * It is revealed in the Christmas Episode of Azumanga Daioh that Tomo was under the impression that reindeer were completely fictional, and treats anyone who mentions them as though they had admitted to believing in Santa Claus.

Film - Animated

 * Megamind: "There is no Easter bunny, there is no tooth fairy, and there is no queen of England!"
 * Happy Feet 2: Will the Krill believes black holes are myths to keep people in the swarm.

Film - Live Action

 * The Film Crew: Kevin Murphy believes in many different fantasy lands, but claims that Spain is a myth.
 * The Muppets: "I think that's just an internet rumour. Like that there's a country called Turkey."
 * Somewhat averted in Look Who's Talking Too. Baby Mikey is sitting awake at night scared. He lists various things he's worried about, and that they aren't real. This includes monsters, ghosts, witches, and dinosaurs. He knows that one of them used to be real, but can't remember which. Justified, since he is a baby.

Literature

 * In more than one Daniel Pinkwater novel, as a throwaway joke, a character claims that Los Angeles does not exist.
 * In the book The Enormous Egg (wherein a New Hampshirian's chicken lays a dinosaur egg), one of Nate's friends says that dinosaurs never existed - some guys found some big bones and made up stories about them.
 * In the Piers Anthony story "Possible To Rue", a young boy's pleas for a pet pegasus leads his father to look the animal up in the encyclopedia and show that they're mythical. So are unicorns. To the father's astonishment, so are zebras, mules, and even horses, which he distinctly remembers placing bets on. It's implied that, by denying zebras are real to avoid having to buy one, the father has inadvertently begun erasing these creatures from the universe.

Live Action TV
""Honey, this is a cult! Yeah! Like the Moonies or the homeless.""
 * In a Christmas Episode of The Middle, Brick explains that Eskimos know how to put a fire in an igloo, only for Axl to snap that back that Eskimos aren't real, but are made-up creatures like leprechauns.
 * There's a Bones episode involving the search for a rumored pirate treasure. Zack expresses surprise that Hodgins believes in pirates, and Hodgins snarks back that they're not Santa.
 * In the US version of The Office, Kevin thinks that mummies are fictitious monsters from the horror genre, and expresses surprise and fear when people tell him that they exist and there are some in a local museum.
 * Semi-example, Karen from Will and Grace about an ex-gay group:


 * On an episode of How I Met Your Mother, Robin believed that the North Pole and reindeer were made up. This is especially weird considering where she's from.
 * In Zoey 101, Michael tries to convince Chase that reindeer aren't real.
 * On Friends Joey and Chandler are both interested in a visiting Dutch woman. Chandler gets an edge by "guessing" that Dutch people come from somewhere near the Netherlands (the place they really come from). Joey responds, "Nice try. See, the Netherlands are this make-believe place where Peter Pan and Tinkerbell come from."
 * Doubly funny because Peter Pan isn't actually from Neverland. He just lives there.
 * During an episode of My Name Is Earl, Randy tries to make a list of famous rich people he and his brother could borrow from, like The Beverly Hillbillies. Earl points out that they're fictional TV characters, "just like Richie Rich and Donald Trump".

New Media

 * (The Customer is) Not Always Right has a few examples:
 * Native Americans
 * Japan
 * Hairless rats
 * A British soldier who declared that "Real, live buffalo don't exist!" features in this (non-fatal) tale at the Darwin Awards.
 * This tale from Snopes about a guy who tries to pay with a $2 dollar bill.

Newspaper Comics

 * In Get Fuzzy, Bucky tries to tell Satchel that Hawaii is a myth perpetrated by the Liberal Media. When Rob informed him otherwise, he reacted with genuine surprise, "It is?? Then why the %*(# DON'T WE LIVE THERE?"

Video Games

 * In Team Fortress 2, the Soldier will declare that Scotland is not a real country, and thus the Scottish Demoman is actually "an Englishman in a dress".
 * World of Warcraft has an in-universe example regarding the Deeprun Tram. Goblins who run the Horde zeppelins claim it's a myth, as they're jealous of the Alliance gnomes who built the tram, and are confident that most Horde citizens will never actually see it. Indeed, it's very hard for a Horde player to get to one of the Tram entrances without being killed by the Stormwind or Ironforge guards.

Web Animation
"Grif: No, like a puma. It's a big cat, like a lion. Sarge: You're making that up. And later... Sarge: (pointing at the front of the Warthog) Look, see these two two hooks? They look like tusks, and what kind of animal has tusks? Grif: A walrus. Sarge: Didn't I just tell you to stop making up animals?!"
 * Red vs. Blue Episode 2:

Web Comics

 * Chainsawsuit has a strip appropriately named "The Australia Hoax".

Western Animation
"Homer: Lisa, vampires are make-believe, just like elves, gremlins, and Eskimos."
 * Likely the Trope Namer, Homer does it in The Simpsons "Treehouse of Horror IV":

"Wiggum: Everybody's heard of an angel, who ever heard of a "neanderthal?""
 * In another episode of The Simpsons, Bart refers to Michael Jackson on a list of fictional things adults make up to scare children. Interestingly, in an earlier episode Bart was a big Michael Jackson fan.
 * In an episode of The Simpsons where they find the skeleton of what looks like an angel, Lisa postulates via Imagine Spot that it may be a Neanderthal who had been attacked by two big fish biting each of his arms simultaneously.

"Hank: So you agree with me that this is impossible!"
 * Combined with Girlfriend in Canada in another episode. At an ice-skating event, Moe insists that all figure skaters are gay. One of the skaters points out that this is a common misconception as he has a girlfriend in Vancouver, to which Moe retorts, "Made up girlfriend, made up city."
 * When Homer opens a bird watchers guide, he's surprised to learn that roadrunners are real.
 * In The Venture Brothers, "Ghosts Of The Sargasso" Hank speculates that if pirates are real, Santa and the Tooth Fairy could be real. Brock points out that no one said pirates weren't real.

"Garfield: There's no such place as Wyoming. Think about it. Have you ever met anyone from Wyoming?"
 * From the Garfield and Friends episode "It Must Be True":

"Reporter 1: I bet this means Bigfoot is a fraud too! Reporter 2: And UFOs. Reporter 1: And hobos. Dib: No wait! Those are real! Except the hobos. Wait, no. They're real. I... I guess. But- what's wrong with you people!?!"
 * In Invader Zim, after Dib proves that "Chickenfoot" is a fraud.


 * In The Adventures of Jimmy Neutron, Jimmy's friends are positive that ancient Egyptian curses are a myth, just like the Loch Ness Monster and North Dakota.
 * In one episode of The Fairly OddParents, a giant squid is treated as a mythical creature... until one actually shows up.

Real Life

 * Surprisingly there's people out there that don't realize reindeer are real animals. Though obviously they don't really fly or have red noses, and are far from tiny, they can be and have been trained to pull sleds.
 * Some people are also unaware that a wolverine is a real animal, and not just an X-Men character.
 * Also, some people don't realize that narwhals are real, judging by the comments on this clip.
 * There are also people who believe that Tigons and Ligers are fictitious, and that photographs of them are actually fake.
 * Snipes are real. Well, there is a type of bird called a snipe. The thing you're sent hunting for might or might not be it, if it's anything at all.
 * The platypus is such a bizarre-looking animal that when it was first discovered, many European naturalists believed it a hoax.
 * Some people don't realize Tasmanian devils exist until they look it up.
 * An interesting effect is as follows: Something is depicted in fiction. Thus, people assume it isn't real. Tokyo neighborhood Nerima, for instance, does exist. However, because Ranma and Nuku-Nuku don't, some people think the neighborhood itself doesn't exist either.
 * “You mean Japan’s a real place?! Well, you learn something new every day!”
 * From the Darwin Awards website: "Real, live buffalo don't exist!"
 * US professor fired after telling student ‘Australia isn’t a country’
 * There are more than a few stories -- some Urban Legends, some well documented -- about retailers in the United States refusing to accept two-dollar bills, believing the perfectly genuine currency to be either bizarre counterfeits or play money. Snopes has a page about one such incident, which actually resulted in the cops arresting the fellow offering the bills away until the Secret Service could tell them they were perfectly valid.