Most Writers Are Human

"That cloud of stars is our galaxy, the Milky Way. Our solar system is on the edge of it. We hurl through an incomprehensible darkness. In cosmic terms, we are subatomic particles in a grain of sand on an infinite beach. ... I wonder what's on TV now."

- Calvin

... at least for those we can prove. There are non-human writers, by the way. These include a few computers, and most likely a few higher primates (writing very simple works, granted, and probably dictating).

People prefer characters they can relate to. This is why most fictional characters are H. sapiens instead of, say, T. rex or A. oryzae.

Besides the large number of stories concerning humans on Earth, this manifests in three major ways:
 * For one species that evolved on one planet, humanity sure gets around in the fictional multi-Verse. Countless Speculative Fiction settings without Earth include humans, usually just like the ones we're used to.
 * Non-human characters, particularly in a story without humans, tend to act just like humans; while degrees of anthropomorphism vary, human-like intelligence, behavior, and psychological quirks and a fully developed verbal language are almost guaranteed.
 * When compared to non-human characters, humans are almost always The Mario. The Five Races or sapient aliens, taken as a whole, will be different from humans in ways that balance each other out. This is odd, since it would be more likely that humans deviate from the average in some way or another.

The inevitability of this varies by medium; after all, most actors are human, too. There are, however, more non-human actors than non-human writers, at least to anyone's knowledge.

See also Earth Is the Center of the Universe, Human Aliens, Humanoid Animals, Aliens Speaking English, Humans Are Special and Humans Are Average. This can wind up being What Measure Is a Non-Human? writ large.

Compare Anthropomorphic Shift, where an entirely non-human cast gradually slips into this trap. As such, this is one of the major sources of Furry Confusion. Sometimes characters are clearly not human but use phrases like "I'm only human" anyway.

Can cause a certain amount of confusion if Humans Are Bastards or Humans Are Morons.

For much more on this subject, see this series of Limyaael's Fantasy Rants. See Xenofiction to compare and contrast.

Film

 * This trope was actually a fairly major factor in the writing of the recent Transformers movie, with the human characters taking a somewhat larger role than is traditional for the franchise. (This was also for pragmatic reasons; every single frame of one Transformer or more that appears on screen took twenty-four hours to render.) According to The Powers That Be, the main reason was the expense of the detailed robots.
 * In the second film, however, there are many more non-humanoid Transformers, of all shapes and sizes, from insects to tiny spheres that roll through small spaces and assemble into one robot when it's gotten where it's going. One character is even  There's also more robot screentime than in the previous film.
 * The Dark Crystal is set on an alien world with several different sentient species. Some are humanoid, if odd-looking (they're like elves or dwarves and some have wings), others are much less so. Guess which ones are the heroes?
 * Probably the strangest example: Why are there lemurs in Disney's Dinosaur? Seems the writers thought us selfish primates wouldn't like the movie unless there was something cute and furry to relate to.
 * In Labyrinth, the two central roles of Sarah and Jareth are occupied by humans, while muppets are relegated to supporting roles.
 * Lampshaded in Martian Child, which is about a sci-fi writer who becomes an adoptive father. When talking about a book of his he talks about how humans are always present in a sci-fi story so that they serve as a stand-in for the reader and allow the reader to identify with the major characters. He goes on to note that he doesn't actually identify most with the human characters himself, but rather with an alien.
 * In all the preview ads for Monsters vs. Aliens, the focus was on the monstrous-type monsters. Then the movie itself came out... and our viewpoint character is a normal human woman who was turned fifty feet 49-feet 11-inches tall by a meteorite. Apparently they didn't think we could focus on a really monstrous monster, so they gave us a dressed-up human.
 * Tron, where computer programs are shown looking like humans. Their appearances are even modeled after their programmers. This is true to the point that everyone thinks Flynn (the human transported into the computer) is a program whose User is Flynn.
 * All the major protagonists in Star Wars are human. The only alien who plays a major role is Yoda, and he is treated just like a very short, elderly human. R2-D2 is less humanlike, but he's more of a functional Team Pet than a character. Chewbacca is a main character, but had essentially zero personal effect on the plot.
 * James Cameron invoked this trope in his Word of God interview to explain why the Na'vi of Avatar look so human, published in the December 2010 issue of Discover magazine. Word-for-word, he says "...science fiction is not made for a galactic audience. It’s made by human beings for human beings."

Literature

 * Parodied to hell and back in that scene in Mostly Harmless where Arthur is looking for a planet of humanoids and must seek advice from a very alien Alien.
 * Piers Anthony:
 * His Cluster series is a complete aversion. Anthony takes great delight in describing some Starfish Aliens, including a species that rolls around on giant ball-bearings (which also play a part in their reproductive cycle), one that rides on magnetic force lines and communicates using biologically-generated laser beams, and one that eats gasses and gets around by jet propulsion.
 * His Virtual Mode series introduced a creature from a reality based on the Burgess Shale.
 * David Brin's Uplift series delights in mixing the viewpoint characters between humans, Uplifted Earth animals, and aliens ranging from humanoid-but-doesn't-think-like-humans to Starfish Aliens.
 * The often-reprinted short story "The Dance of the Changer and the Three" by author Terry Carr (not Terri Garr) both applies and subverts this trope. It is narrated by a human but concerns a race of pure-energy beings whose very motives are unclear even to the narrator as well as the reader.
 * Weirdly applied in Dinotopia. We're assured that only about ten percent of the population is human; everyone else is an Intellectual Animal. Funny, the illustrations suggest otherwise...
 * Bolo Novels are often done from the point of view of the large sentient battle fortresses. The biggest trouble is making it relate to an AI that is usually identified as 'smarter' than human. So many plot devices to either limit their out of combat AI or to have them damaged is the norm, with full Battle Reflex Mode having them figure out how to kill the enemy in .02 seconds and spend the rest of time in Battle Reflex Mode analyzing Music while carrying out the plans. It's also presented that it's a good thing that they are hard wired to be Knights in Shining Armour, because Humans Are Bastards too often.
 * The Xenofiction novel Raptor Red has a weird variant on this; most of the story is about a female Utahraptor's adventures, but for two chapters in the middle of the novel we are treated to a random subplot about an insectivorous little mammal, mainly because he's one of humanity's ancestors.
 * It is, however, a rather entertaining subplot...
 * Literally averted (sort of) in a segment of Godel Escher Bach an Eternal Golden Braid; a student of the author once designed a computer program to produce artificial Zen koans, and one early result is part of the book. Amusing, as a programming error caused the computer to print out a bit of code instead of an English word in one place.
 * Also literally averted by Atlanta Nights, where chapter 34 is produced by "Bonsai Story Generator". It fits as well in the story as any other 2 chapters not named 4 and 17 (which are exactly the same).
 * In Warriors the cat have such human-like qualities and intelligence that they can do dexterous actions like splinting a broken leg. The cats also live in Clans (unlike real cats) and the bad guys are racist. The author even says she doesn't think about cats when coming up with ideas, giving them more humanity-based themes.
 * Poppy seeds are used in the series as a sedative/painkiller. While poppy is sometimes used in painkillers for humans, it's actually poisonous to cats.
 * A more obvious example: Firestar's most distinguishing feature is his red pelt and an entire prophecy revolves around it. In Real Life, cats can't see red.
 * Nearly every novel in the Star Wars Expanded Universe puts humans - and humans from the movies, at that - in all of the important positions. The same two human women switch back and forth as President of the New Republic. Humans are the important Jedi, the major heroes, the minor characters, and quite often the major villains. Nonhumans are relatively rarely in prominent positive roles; they're typically the minor villains, the Non Human Sidekicks, in supporting roles at best, though sometimes they do manage to be Scary Dogmatic Aliens. Some books try to justify this by saying that when the New Republic was the Rebel Alliance it was humans who founded it and those who survived stayed in power, and that humans are probably the most populous species out there.
 * The major exception is Timothy Zahn's books. Nonhumans are in a great many of the human roles, and it's not really remarked on. In the Hand of Thrawn duology, the President of the New Republic is a male Calibop, for example. Minor villains tend to be humans and aliens both. Aliens in prominent roles often do explicitly think differently than humans do, and design different settings. When any specific group is homogeneous or nearly so, Zahn gives a reason. Imperial doctrine favors humans. Chiss are isolationist. So on.
 * Exceptions like Admiral Ackbar and Borsk Fey'lya tend to be either from the movies or made by Zahn. Zahn actually gave a sort of vague nod to this trope by making an Imperial human head out away from Imperial Center, and think in disgust about how humans are so few outside of, well, human-controlled territory.
 * Also lampshaded in the Coruscant Nights series, where a particular alien character spends a while musing over how humans are so ridiculously common in the galaxy, and how because of this, everything is built or designed to their standards. That series had a few more alien leads then usual, but the humans were still much more common.
 * Not to mention the underrated Alien Chronicles series, written by Deborah Chester and commissioned by LucasFilm, which thoroughly subvert this trope by taking place in a universe populated exclusively by various alien species (left over from the Star Wars character design bins, as a matter of fact).
 * JRR Tolkien invoked this in one of his letters regarding Middle-Earth. The gist was that such fantastic stories should be centered on humans, since when you get down to it, a human writer won't be able to portray an elf as anything but a man in a funny suit.
 * And yet, The Hobbit has no actual humans as main characters - unless you count Gandalf, but he's gone for a good half the book (and isn't really a human, anyway, but a being not unlike an incarnated angel), instead focusing on dwarves and a hobbit, and The Lord of the Rings only has two major human characters out of nine (three if you count Gandalf), one of which dies. Though Aragorn plays some important roles early on, and Boromir has the memorable death scene in book two, the first large-scale plot involving humans is Rohan. In Book Three. Do as I say, not as I do?
 * Maybe, but bear in mind that hobbits are supposed to be a sub-species of humans that evolved a culture of their own, albeit their nature remains simply that of pacifistic short humans as opposed to immortal elves.
 * In Stephen R. Donaldson's Chronicles of Thomas Covenant, he basically takes all of the varied races of Tolkien and makes several of them variations of humans.
 * Subverted and played straight in the Vernor Vinge book A Fire Upon the Deep. Humans are only one of a vast multitude of advanced aliens in the galaxy, and the main cast of characters includes aliens that are essentially mini-Hive Minds or sentient plants. Several times we see messages sent by aliens that are so alien that even the Super Advanced Translation Technology this universe contains can't keep up.
 * However, the book is still mostly about humans; humans play the deciding role in whether or not the galaxy will get eaten by the Blight; and most of what we see of the interstellar internet is a posting group called "Homo Sapiens Interest Group." Which contains all humans as well as a number of alien races that just think humans are cool.
 * Lampshaded in prequel ("Deepness in the sky").
 * Averted in Black Beauty, which is written from the first horse -- not first person -- perspective.
 * Purposely invoked in the Isaac Asimov short story (and later novel) "Nightfall"; the aliens are made as human as possible so that their plight resonates with the reader.
 * Asimov purposefully avoided aliens in most of his books, precisely because he was frustrated with this trope. "Aliens" created by other authors never felt realistically alien to him, and his own efforts impressed him no better. As a result, most of his aliens are unabashedly humans-from-other-planets, caused by the plot requiring a species from another planet to work ("Nightfall" can't take place on Earth, or really involve someone with knowledge of the larger universe, for example). His most notable effort at creating truly alien aliens would be for The Gods Themselves, but while they are quite alien biologically, they still sound a lot like humans in character.
 * Averted and hard by Peter Watts in his uber-hard novel Blindsight where the alien is truly alien and even the human characters are alien.
 * Arthur C. Clarke nicely averts this trope in his Rama series. The few times any aliens interact with humans, great lengths must be gone to for an exchange of ideas to even become possible.
 * Embassy Town somewhat averts this trope, as well as justifying it: the Hosts are very much not human, but become more human in their thinking (although still remaining Starfish Aliens) by the end of the book because of the actions of their human neighbors -- and even then they are markedly different from the human characters. Humans make up the entirety of the main cast however, and it takes a long time for important Host characters to show up, of which there really are only three in the whole book.

Live Action TV

 * The various Star Trek series: for all the non-human races around, the captain of each ship is always human and the crew is always primarily human. Getting more multicultural, but almost all human cultures.
 * There have been a goodly number of on-screen portrayals of Vulcan Starfleet captains. Vulcans are so hugely humanoid you may or may not even bother to count that, though.
 * To be fair, economical effects are a fairly recent thing, so you will only see very alien non-humanoid races in the films and more recent series. (Which sets up one heck of a Continuity Snarl in Star Trek: Enterprise.)
 * It's implied that, despite the Federation being one body, Federation ships tend to be made up of primarily one race. There are a couple instances where we meet all-Vulcan Federation ships, or of new crew members coming aboard who are only used to dealing with their own race.
 * Given the prevalence of Bizarre Alien Biology, it would probably be economically unsound to make a true multi-species vessel.
 * According to Jacqueline Lichtenberg, that's no excuse.
 * That's true -- it is also, however, established (in Star Trek VI: The Undiscovered Country) that Starfleet is pretty human-dominated as an institution, although that's from the Klingon point of view, so take it with a grain of salt the size of (what's left of) Praxis.
 * Which is, granted, a very small grain of salt. Too Soon?
 * Lampshaded in the recent Star Trek Expanded Universe Titan novels, in which a nonhumanoid crew member takes bets on whether the ship's motto will be a human proverb despite the extreme diversity of the ship's crew, and loses when the Vulcan saying "Infinite diversity in infinite combinations" is chosen. He asks whether Vulcans count as human, as they're far more humanlike than a cybernetically-enhanced featherless ostrich with a prehensile tail...
 * Unintentional lampshading in The Pilot of Star Trek: The Next Generation, when Deanna explains "I'm only half-Betazoid, my father was a Starfleet officer." Yep, "Starfleet officer" = "human" according to a half-Betazoid Starfleet officer.
 * In the Expanded Universe, there is a Starfleet vessel with an all-Horta crew.
 * Despite the fact that the show stars a Human Alien called the Doctor, Doctor Who usually tends to take place on Earth or on Earth colonies or generally to involve humans in some way. The Doctor has almost always had human companions.
 * Russell T. Davies is a well-known practitioner of this trope in his Doctor Who work. He has opined more than once that people don't want to see "Zog Monsters" on the "planet Zog" and only gradually introduced alien planets into the series. In the first three whole seasons of his Doctor Who, more than half of the episodes happened on Earth. The others visited human-made satellites, other human-settled worlds, and even human colonies in deep space... but only one locations visited in those 41 episodes was not dominated by humans (and even then, the most important guest star was, wait for it, a human -- although barely recognizable as such)
 * The entire first season never left Earth (or a satellite around it) until early in season two, Rose said "you promised me a planet, remember?" So we go to... "New New York" on New Earth, and from then on, Earth colonies on non-Earth planets were fair game. Utopia, part one of the three-part season three finale, was the first time they went to another planet that wasn't an Earth colony. The new series has generally focused on time travel over space travel in general, even in non-Davies stories -- and even after Davies left.
 * The speculative documentary series Life After People suffers a mild version of this in that, despite the title, more emphasis is given to the nonliving artifacts of human civilization than what happens to actual living animals. However, the show still covers possible evolutionary paths for the animals that we've domesticated or kept in zoos.
 * Despite Muppets being the stars of the show, Sesame Street commonly leaves it up to the humans to give advice and guidance to Big Bird or Elmo. Probably justified, as a child audience is more likely to recognize that adult humans are adults, and therefore authority figures, than puppets.
 * Subverted on The Muppet Show, in which the only humans are guest stars who take their cues from Kermit and the gang.
 * Farscape somewhat averts this and somewhat doesn't -- technically there is only one human character in the entire show (if you exclude Jack, who is usually either a memory of John's or an insectoid Starfish Alien in A Form You Are Comfortable With), many of the aliens who are encountered are Human Aliens (especially Sebaceans, who basically are humans), and most other aliens are Humanoid Aliens who behave like humans for instance Delvians(despite being Plant Aliens), and Luxans. There are a few aliens who either look (Hynerians, Pilots, Scarrans) and/or behave (Leviathans, Ancients, Drak) quite different from humans, however.
 * Nebari are an interesting example: they're Humanoid Aliens but their mindset is markedly different from humanity's. Of course, Chiana, the Nebari we see the most of, is a nonconformist rebel who actively rejects her species' values.

Radio

 * Parodied in one of the Ig Nobel "award" ceremonies, with a speech by Neil Gaiman which "proved" that virtually all books are written by bacteria. But most of them are still about humans, for some reason.

Tabletop Games

 * Warhammer 40000 has this happening a lot. Humans are the main focus in most of the stories. In fact there has only been one series focusing on the Eldar and one book for the Tau.
 * Somewhat justified though, as an Ork book would probably at best be a comedy with a simple plot, a Necron story would probably be mostly about sleeping (unless it is set during the creation of the Necrons, which would be interesting), and a Tyranid book would be all about how hungry the hive mind is, though it could be used in an interesting Xenofiction way.
 * Averted in the Lorwyn/Shadowmoor setting in Magic: The Gathering. You've got elves, halflings, merfolk, giants, trolls, duergars, hags, and angry donkey-men (noggles), but no humans. The development team deliberately went out of their way to create a setting where none of the characters or races could be played by a human in makeup or a suit.
 * But seen in a rather straightforward fashion before, when there were no new merfolk for years apparently simply because "they wouldn't be any good fighting on dry land". (It could also be argued that the trope does shine through in the Lorwyn/Shadowmoor blocks by virtue of omission -- after all, why should a setting without humans be any more "special" than one without dwarves or rat-people otherwise?)
 * In the great majority of fantasy settings (and science fiction too, for that matter), humans are always the dominant and major race.
 * GURPS invokes this trope and all but refer to it by name. All customization is done by adding or subtracting features from a human template.
 * GURPS Discworld briefly invokes Humans Are Special to explain why humanity dominates the Disc instead of trolls, dwarfs or banshees, before acknowledging that the real reason is that the setting was created by humans, for humans.
 * The rulebook of Nobilis specifies that Nobles (usually) start off as humans, in order to ground its rather strange and abstract into something approaching the human experience. Therefore players generally portray former humans (versus former something elses).
 * Averted and played straight in Rifts. While the vast majority of D-Bees in the game are humanoid, there are quite a few playable races that qualify as Starfish Aliens. Also, though a large percentage of the settings in the game are ruled by/predominantly human (it is Earth, after all), there are several locations where humans coexist with aliens, are enslaved/dominated by aliens, or humans aren't found in large (or any) numbers.

Video Games

 * Many fans of Mass Effect believe this is the reason why Shepard could engage in a sexual relationship with Liara (an Asari, the most human-like alien in the game's universe), but not with Tali, Garrus, or Wrex, all of which are very inhuman physically (especially Wrex!).
 * This is totally averted in Mass Effect 2. Not only does the game allow you to have sex with the quarian, turian, drell or asari members of your crew, but the ship physician will send you notes on the relevant precautions. For example, he prescribes antibiotics to the quarian (to lessen- not eliminate- the aftereffects that out-of-suit exposure will have on her) and warns against "consuming turian tissue" (as it may cause an allergic reaction).
 * Also fits in the game's usage of humans as the Jack of All Stats, to an extent. Of the council races, salarians are known for being extremely intelligent, asari are known for their diplomatic talents, and turians are known for their military. The game lampshades this to an extent, by pointing out the talent diversity of humans. In the second game, Mordin even mentions that they have more genetic diversity than any other species, which is presumed to be the reason the collectors chose to target them over other species for  (though no explanation is given for why humans might have more genetic variance).
 * Despite the number of various species existing within the Final Fantasy universe, the main characters have by and large been human or at least some sort of Half-Human Hybrid that looks identical to humans most of the time. The main aversions are the MMORPG entries, Final Fantasy XI and Final Fantasy XIV where the player picks their character's race and even then, the selectable races are far more human-like then say a Tonberry or Moogle.

Web Comics

 * In SERGOM is is shown that while not one of the cast are human, they all act and go through their lives in a completely human manner. In fact, without the glaring visual representation that the crew aren't human, they can be mostly considered to act like humans.
 * The aliens in Schlock Mercenary are pretty varied physiologically (a being with two separate radio-linked bodies, a flightless avian with a prehensile tongue, a round...thing with four limbs evenly distributed on it's body, various genetically engineered terran animals, various AIs etc.), but most of them act human to a large degree, generally in the interest of humor.
 * In Harkovast there are no humans, but all of the races are very human in their behaviours.
 * In Dragon City, the comic is about a race of dragons that live underground unbeknownst to the humans, but due to human culture saturation, the dragons essentially act human.
 * The Ambis in Jix are an alien race who act like Ancient Romans in that they move from planet to planet conquering them to build up their Empire. The main character, Jix suffers from the human mental ailment of split-personality, though being an intelligent race, it's possible that this might crop up in other intelligent races.

Western Animation

 * Wait, shows with E. coli as the main characters? There's always Osmosis Jones, where the cast is made up of red blood cells and fat cells and cold medicine and viruses and... oh, no, wait, they turned all of the characters into humans anyway. Dang, thought I had something there for a minute.
 * Of course, since the show is a Fantastic Voyage, the most of the characters aren't just human, they're A human.
 * When a dog cell got into Hector's body, it had a canine form and habits. Presumably if Ozzy and Drix had visited the dog's body, it would've been set up like a gargantuan kennel.
 * Of course, because kennels are a dog's natural habitat.
 * As much as cities are for humans.
 * Can result in heaps and heaps of Furry Confusion. Consider the case of the Tibble Twins in Arthur.
 * Once Upon a Time... Life features humanoid red blood cells as protagonists. They carry oxygen to cells manned by even smaller humanoids, complete with factories, command centers and vehicles. Given that it's a show about human biology designed for young children, the heavy use of metaphors is justified.
 * Could this be why Santo Bugito, which dealt with a town populated entirely by insects, has been almost completely forgotten?
 * Pixar is praised for humanizing things that are not human. So far, they have only had a few movies where humans were the main characters.

Real Life

 * The hypothetical "Dinosauroid," which was a proposed possible evolutionary descendant of the troodon had it not gone extinct. Dale Russell, the guy who thought up the concept, has been criticized by other paleontologists since the 1980s, many of whom point out that Russell's Dinosauroid is overly anthropomorphic. Most paleontologists think that any possible descendant of the troodon would appear more bird-like than human-like.
 * In a case of All Animals Are Humans, consider how many pet food companies boast of how their dog or cat foods contain only "real meat, not animal byproducts". "Animal byproducts" is a less squicky way of saying "ground bone meal, internal organs, and heads". Guess what parts of a kill predators in the wild tend to chow down on first? But no, our pets are just little furry humans, and have to share our dietary preferences. We certainly wouldn't want to give our dogs something made from bones, now would we? Oh, wait...
 * Also, people in many cultures have no problem eating internal organs and heads (see Foreign Queasine), so it's not just human dietary preferences that our furry friends must share, but the preferences of a particular subset of humans (wealthy Westerners). Bone meal, on the other hand...