Improbable Species Compatibility



When a Skitty and a Wailord love each other very much...

The usual intermediary step between an Interspecies Romance and a Mix and Match Critter.

In Video Games where you Gotta Catch Them All, and where "them" are Mons, often the only way to acquire every last critter in the game is to, well, breed them.

This may involve somewhat conventional animal husbandry, or stranger things, but the important thing is that there are not always reasonable limits on what can be bred to what.

Pokémon provides an extreme example: Skitty is a two-foot tall housecat-like Mon, and Wailord is a forty-seven-foot long whale. Yet because the game places both of them in compatible breeding groups, a player can pair them up and produce viable offspring of either gender. The Pokémon fandom uses the term "Hot Skitty-on-Wailord Action" (HSOWA) for pairings like this, which originated on GameFAQs. (Bulbapedia, the largest Pokémon wiki, describes the term's etymology in further depth for those interested.)

In a broader sense, this may apply to any work of fiction in which two grossly dissimilar species are somehow capable of interbreeding. This pretty much misses the point of the term "species", which is supposed to indicate which animals can breed successfully in the first place.

If the result of this unholy union isn't a Half-Human Hybrid or some variety of Mix and Match Critter, then Gender Equals Breed may very well apply, with the offspring being strictly one of its parent species.

Still, as strange as this may seem, there ARE species in the real world which display such extreme dimorphism that they have been categorized as wholly different species in the past. Anglerfish males are basically parasitic appendages to females, for example. This just might be one of these cases.

The unintentional (or intentional) ability to produce this phenomenon is attributed to Gameplay and Story Segregation.

Advertising

 * This ad for lubricant gel.
 * An older ad for Red bull had a (male) dauchsund followed by a (female) dalmation, and a trail of half-breed puppies, the dauchsund then illustrates how he made it work.

Anime and Manga

 * Inuyasha's father and mother. The Inu no Taishou does have a human form, but his true form is the size of a mountain.
 * Dragon Half features, unsurprisingly, the offspring of a human and a dragon. She basically looks like an adorable teenage human girl with horns and a tail, she's super strong, and her name is Mink for some reason.
 * Let's not forget Princess Vina. When you're tired of looking at her humany cuteness, drop a heavy weight on her and go “Aw!” over her slime-moldy cuteness.
 * Both of those involved shapeshifting from a non-human into a human form. Vina was born as a slimemold, she had to learn magic to change into something humanoid.
 * In One Piece, there are people called "Wotans", a hybrid race of Fishman and Giants. While Fishman are generally taller than humans, Giants are dozens of feet tall, which brings up a intresting question of how that works.
 * There's also, who even as a baby looked about 10 times as big as her mother.
 * That's totally ignoring the whole Mermaid Problem. This is at least partially justified if they, uhm, reproduce like fish. But that giant baby had to come from somewhere, and Queen Otohime is a goldfish mermaid.
 * Basquash teases a coupling between Sela and Naviga. The problem is that Sela is a moderately-sized (albeit thin) human woman and Navi is a friendly, twenty-foot tall giant. Considering Sela goes on and on about getting the "genes" from the best Basquasher around, and Navi is pretty damn good, well... try not to think about it too hard.
 * Spice and Wolf carefully dances around this issue; Holo only transforms three times (once only her arm), and the first two times Lawrence is initially afraid of her, but by the third time he seems to have become comfortable with her wolf form. However, all of their tender moments come when she's in her Little Bit Beastly "human" form.
 * Spice and Wolf carefully dances around this issue; Holo only transforms three times (once only her arm), and the first two times Lawrence is initially afraid of her, but by the third time he seems to have become comfortable with her wolf form. However, all of their tender moments come when she's in her Little Bit Beastly "human" form.

Comics
"Eddie: This is eighteen different flavors of disgusting. Bertha: What can I say? I dig brutish guys in leather!"
 * Cerebus the Aardvark got it on with a human woman and had a mostly-human child. Apparently all the dominant aardvark traits manifest in the toes.
 * The article Man of Steel, Woman of Kleenex details just why Superman can/should not reproduce with human ladies. Of course, given how often his powers change, this probably won't be what stops Superman and Lois from having children.
 * In a Johnny the Homicidal Maniac sidestory comic, some really, really stupid aliens visit Earth and force a man to Mate or Die with a chicken in order to study human reproduction (they thought the chicken was a human female... Did we mention they were really stupid?). The result are freakish half-human half-chicken hybrids, with the details of their conception and gestation being blessedly skipped over by the story.
 * Fire Breather stars the offspring of a pairing between a human woman and a giant dragon, which resulted in a scaled, orange skinned, four-fingered, but essentially human-looking offspring. She tried to explain how this happened, but we don't know because her son covered his ears. Apparently it was quite simple.
 * The minor Marvel character Epsilon Red is only able to survive in a vacuum. Shaky science, but fair enough so far. In a flashback (set well after he was turned from an ordinary human into a spaceman), his wife is shown to be pregnant. Think about that for a moment.
 * Nodwick also made fun of squeamishness about orcs being so not Bishounen, in Anserinian royals arc:

Fan Fiction

 * There has been at least one Deep Space Nine fan fic where Odo and Nerys not only have intimate contact but their union produces an offspring.
 * If Changelings are anything like Amorphs that could result in a relatively simple birth on either partner for so many reasons.
 * There exists a Chronicles of Narnia fanfic in which there were many not-oblique-enough references made to Ettins (akin to extremely large orcs) who abducted humans (men, surprisingly) in order to produce magically-viable offspring, since generations of inbreeding and incest had destroyed the health of the Ettin line. The abducted humans usually didn't survive much past the experience.

Film
"Timon: Shenzi Marie Predatora Veldetta Jacquelina Hyena... would you do me the honor of becoming... my bride?
 * One script of Galaxy Quest has this ending for Fred and Laliari. Thankfully this was not shown. (Laliari is a Thermian, a species of Starfish Aliens who look like an octopus eating a squid. She uses a hologram to "dress up" as human, but apparently takes it off to have sex. "Ohhhh that's not right" indeed!)
 * In the sequel to Hellboy, it is discovered that  The film never explains exactly how this works, but in the comics Hellboy is , which may help explain it.
 * In Meet the Feebles by Peter Jackson, an elephant named Sid is said to have had sexual relations with a chicken. Said chicken then brings up a paternity suit against Sid, who claims the baby isn't his ("She slept with half the chorus!"). It becomes apparent, however, that the baby was, in fact, fathered by Sid, as it's seen that the baby is a cross between a chicken and an elephant.
 * Also the boss of the theater (a walrus) is having an affair with his secretary (a cat). On screen.
 * Shrek 2, at the very end, shows Dragon and Donkey's offspring. According to the action figures, they're called "Dronkeys". They're pretty strange-looking, too. Amusingly enough, the gag started life when the first movie came out, as a short comic in a Mad Magazine. The animators probably thought "Why the hell not?"
 * "Look at all our little mutant babies!"
 * The Golden Child has Kala, a female human/dragon hybrid, one of whose ancestors was supposedly raped by a dragon.
 * Interspecies prostitution in District 9. Apparently, The Prawns are hermaphroditic, and have organs for both options. Brainbleach, anyone?
 * Referenced in The Lion King 1½, where Timon proposes to Shenzi.

Shenzi: (pending several seconds of shocked horror from both sides) I don't think so!

Timon: Shenzi Marie, please. I know what you're thinking: "We're too different." "It'll never work." "What will the children look like?"

Shenzi: Ooh, that violates so many laws of nature!

Timon: Listen to me! The problems of a couple of wacky kids like us don't amount to hill of termites in this nutty circle-of-life thing. And so I ask you: If not now, when? If not me, who? I'm lonely..."


 * Given how real-life Hyenas work, he'd be in for a surprise...
 * In Ralph Bakshi's Wizards, Elinore is a human size half-human/half-fairy. Her mother was a fairy. Ouch.

Literature

 * In Glen Cook's "Garrett P.I." books, the main character's homeland of Karenta is full of this. Because the human empire is at war, many jobs have been filled by various creatures (trolls, dwarfs, elves, etc), all of which seem to be able to breed with each other and humans, sometimes in such variety that it's impossible to tell exactly what a creature is unless you know their great-grandparents.
 * In the Xanth novels, any two species of creature are capable of breeding and having viable offspring. The result is either a Biological Mashup like a centaur or a winged centaur or who knows what else, or a were-creature of some sort. All of the chimeric creatures in Xanth, such as mermaids, are literally the result of interspecies breeding. This is due to the abundance of unmarked, naturally occurring Love Springs, which (generally) cause unsuspecting people and animals who drink the water to immediately and involuntarily mate. It also magically ensures offspring. This is a rather abrupt and off-putting experience, so those cross-species couples actually interested in enjoying the experience generally use 'Accommodation Spells'. Perhaps the best example of this is the case of Becka from Dastard. Her mother was a young maiden who fled into water while being pursued by a dragon. As it turns out, the water was a Love Spring and the dragon was a male... Becka is an example of the were-creature phenomenon, being able to swap between cute girl and hand-chomping dragon forms.
 * In Harry Potter, Hagrid's mother was a giantess (in this universe, violent, 20-foot-tall humanoids) and his father was an ordinary, if somewhat short, human wizard. In the fourth book, he asks Madame Olympe, another half-giant, which one of her parents was the giant - so apparently, some females managed. Hagrid himself also bred manticores (creatures from Persian mythology with the head of a man, the body of a lion and the tail of a scorpion) and fire-crabs (tortoises with jeweled shells that shoot fire out their rear ends) to produce blast-ended skrewts, which resemble 10-foot, headless, armored scorpions that move by jet propulsion. In this case, more than justified by A Wizard Did It (albeit a failed one).
 * In the Potterverse, cross-species breeding is strictly monitored by the Ministry of Magic, and experimental cross-breeding without Ministry supervision is a criminal offense.
 * A Song of Ice and Fire author George R.R. Martin apparently had the same mechanics-related thoughts. In the far north of Westeros, humans are occasionally abducted by giants. Abducted men have produced half-giants who have since further interbred with humans. The abducted women... don't survive.
 * There is a rather horrid image in Sir Thomas Malory's Le Morte Darthur about a giant who has abducted the Duchess of Brittany: Squick!
 * In "The Dunwich Horror", human woman and an Eldritch Abomination locked out of time and space have some rather... unique offspring.
 * For extra squick, the woman's father may have acted as an, er... intermediary.
 * "The Dunwich Horror" is itself a Shout-Out to Arthur Machen's The Great God Pan, where the eponymous deity impregnates a woman who was surgically modified to be able to perceive Him in all His glory, and was instantly driven insane by the experience. The child was physically more human than in Lovecraft's tale, though.
 * In the Discworld novels the reason for all the Mix-and-Match Critters in heraldry is because the heralds insist on drawing all the designs from life, and there's not really enough space to keep all the animals, so they get a bit... close.
 * Guards! Guards! has the swamp dragon Errol and . He can sit on a person's shoulders while she.
 * It's mentioned in Snuff that an unnamed dwarf and troll have set up housekeeping together. Perhaps fortunately, Vimes is cut off before he can ask the inevitable question...
 * The hero of Tad Williams' The War of the Flowers is shepherded through Faerie by, well, a fairy. Several times people assume they're boyfriend and girlfriend, squicking him out. He later asks how such a relationship would even be possible. The answer? "Surgery." This was a Magitek universe, so this was not a flippant answer. The surgical/sorcerous procedure which could accomplish the deed was a significant plot point. Eventually,.
 * One of the books in Mercer Mayer's Little Critter series entitled "Just a Little Different" has a character that has a turtle father and rabbit mother.
 * In Dr. Seuss's Horton Hatches the Egg, a half-elephant, half-bird was created by the titular elephant sitting on a bird's egg.
 * Which he had no part in creating, one may add. It's supposed to be heartwarming Poetic Justice: Horton did the work, so he deserves to be the mother, even though that's biologically impossible.
 * The issue is raised in The Sacred Diary of Adrian Plass, after Leonard claims that "vquex" is a valid Scrabble word, meaning "the product of a giraffe mating with a ferret".
 * In one of the books in Christopher Stasheff's A Wizard in Rhyme series, the wizard encounters a Dracogriff: the offspring of a male dragon and a female griffin.
 * The Star Wars Expanded Universe has Sith alchemy, which explains why so many species are variants of humans (and presumably capable of playing HSOWA straight), as well as why species hold physiological elements of vastly different taxa, e.g. Mon Calamari having elements of both mollusks and arthropods. Or Falleen having elements of both reptiles and mammals. Basically the Sith were really big on HSOWA.
 * The half-human, half-bird Quetzals in Flora Segunda are said to be the result of human women mating with male eagles. Even in a world with magic, it's hard to figure out how that one would work.
 * In Mary Brown's Pigs Don't Fly (But Dragons Do) the protagonist ends up . This results in by the end of the book Draggone's Eg.
 * The Golden Flower Pot by ETA Hoffmann is a story of a human who fell head over heels for a magical creature looking mostly like a blue eyed gold-green snake and sometimes like a human lady -- a daughter of a salamander and green snake. The green snake, in turn, was a daughter of Lily and Morning-wind. Fairyland family trees can induce vertigo like this.
 * His other books had all Alchemic Elementals trying to know a human closer. And one young man manipulated into unknowingly trying to romance a clockwork automaton.
 * Song in the Silence by Elizabeth Kerner is about a woman who, on first meeting a house-sized dragon, discovers that she possesses the capacity for Truespeech (dragon telepathy). She and the dragon fall in love they can never consummate and wrestle with the implications of this trope until
 * In Reamker (a Cambodian poem based on Ramayana), Hanuman, a vanara woos Sovanna Maccha, a mermaid. They eventually had a child who is a half-vanara half-mermaid.
 * In the Merry Gentry series by Laurell K Hamilton, one of Merry's partners is the son of a female (human-sized) sidhe and a male (doll-sized) pixie. Merry herself also participates in non-reproductive sexual acts with several (doll-sized) demifae.
 * Averted in Animorphs, due to the morphing technology that allowed Elfangor to take human form when he created Tobias with Loren.

Live Action TV

 * On Hercules: The Legendary Journeys, Herc and Iolaus befriended a mixed couple consisting of a centaur male and a human female. And they had a son. Who was also a centaur.
 * Similarly, in Xena: Warrior Princess, human female Ephiny marries and has a child with Phantes, a centaur male. The child is named Xenan and grows up to be an ally of Xena's.
 * In the final episode of Lexx, the . The other parent that helped produce the offspring was . Forget Skitty and Wailord, is way more bizarre. It helps that   is the woman in this situation.
 * An episode of The Golden Girls featured the character Rose dreaming of a peaceful, Utopian future, one where bears would live in harmony with field mice, "But they wouldn't be able to mate or else the field mice would explode."
 * In Eureka, Deputy Andy, an android, has sex with SARAH, the AI of Carter's house. While they could have averted this by just using the finger uplink gag they used in the beginning of the episode ("wrong port"), Andy instead comes walking out of a random door as he zips up his pants. Carter and Jo can only stare in confusion.
 * In Buffy the Vampire Slayer all but the True demons are apparently partially mortal, and many have inferred this means that there was actual breeding going on between them. This seems physically problematic. Two True demons have been seen - Olivikan, an enormous armored insectoid snake creature, and Illyria, a massive, taloned, armored creature with, admittedly, tentacles. Nevertheless, how exactly either of them would go about breeding with a human raises a few questions.
 * Not necessarily - vampires for instance were specifically said to be half-human hybrids because the last demon to leave Earth infected a human with its DNA, thus creating the first vampire (probably a Turok-Han). Other humanoid-ish demons might similarly be the results of viral-infection type "breeding" between true demons and early humans.
 * Averted on Roswell, where a certain type of organism was used to manipulate the human and alien DNA and allow the creation of the human-Antarian hybrid children.
 * Implied in Tracker, given that Mel is revealed to have Cirronian ancestry.

Music
""But now throughout France a new dog breed abounds:" "The famous Marseille Afghan short-legged hound!""
 * The novelty song Buntz! tells of a highly acrobatic tryst between a British ship's-mascot dachshund and a classy female Afghan.

""True love died 'cause nothing fit. That's the long and short of it.""
 * Fatally averted in Little Gomez, in which the randy chihuahua's St. Bernard paramour got bored (and sat down) just a bit too soon.
 * The song The Dragon's Lamentable Love, about a woman and a male dragon.

Mythology

 * Older Than Feudalism: Shows up a few times in Greek Mythology:
 * The Minotaur was born of this sort of a union. King Minos angered the sea god Poseidon by refusing to sacrifice a bull (given to him by Poseidon for that very purpose), so Poseidon caused his wife Queen Pasiphae to fall in love with that same bull. She asked Daedalus to help her, so he built her a hollow wooden device that looked like a cow and enabled her to go tryst with her beloved. Don't think too hard about the mechanics of this.
 * Zeus, that philanderer of mythological proportions (pun very much intended) often seduced human women in the guise of animals, such as a bull or a swan. Or a shower of gold.
 * Aphrodite who was born out of foam on the waves when Cronos -- Zeus' Father -- threw Ouranous's, HIS father's, penis and testicles into the sea. So Aphrodite's birth is not only mind-boggling, it also shows her to be a generation older than Zeus and his siblings. Presumably her mother is Thalassa, an obscure female personification/goddess of the sea.
 * The origin of the centaurs takes the cake: Ixion was invited to Olympus by Zeus. Zeus created a cloud-woman named Nephele that looked like Hera to trick Ixion. Ixion had sex with Nephele, who gave birth to Centaurus. Centaurus, deformed and outcast, lived alone on Mount Pelion and had mated with the mares that lived there, producing centaurs. And now you know!
 * The original Antlion was the child of a male lion and a female ant.
 * The Bible may or may not features this (depending on your interpretation) in the form of the Nephilim. Angelic fathers, human mothers.
 * Many American Indian stories feature the resultant monsters of HSOWA as why species exist today.
 * In Egyptian Mythology, there was a minor fertility goddess named Tawaret, who herself was a mix-and-match-criiter (she was part lioness and part hippo, with some attributes of a human female). And she, being a fertility goddess, was nearly always pregnant...and her consort was Sebek, who took the form of a crocodile. (Who was depicted variously as traveling on her back...or even literally a part of her.) Her Darker and Edgier inverse was the demoness Ammit, who devoured souls deemed "unworthy" when measured against the Feather of Ma'at.
 * Genbu, the Guardian of the North, winter, water, and a minor association with fertility...consists of a giant tortoise having sex with a giant snake. (May or may not be consensual sex, depending on whom you ask.)

Newspaper Comics

 * In one Bloom County arc, Hodge Podge and Rosebud, respectively a jackrabbit and "basselope" (basset hound/antelope) had jackabasselope children.

Professional Wrestling

 * The Iron Sheik, gentleman that he is, once related in an interview about how he walked in on Andre the Giant having sex with an normal sized woman. He likened it to a "bear fucking a rabbit, if the rabbit could get on top."

Tabletop Games

 * From Dungeons and Dragons:
 * The dragons of Dungeons and Dragons can change shape into nearly any living creature, and can mate with anything into which they change shape to produce viable half-dragon offspring.
 * The increased amounts of splat books have brought increasingly outlandish (and Squicky) variants of the above half-dragon, such as the half-infernal and half-celestial, the half-troll, the half-illithid, and even the half-golem (though the latter two have nothing to do with parentage). Most of these, being templates that are applied to other creatures, have far too few limits on what they can be placed on.
 * Several editions of the game have talked about the fecundity of goblinoid races, which include goblins, hobgoblins, ogres, and orcs. They could easily interbreed with each other, with humanity, and with several other species. It seems that developing new monsters for the game mostly consists of finding two creatures already in the game and figuring out what happens when they have sex.
 * See also the Book of Erotic Fantasy. Yes, it's a real book. (though unofficial) Or "The Complete Guide to Unlawful Carnal knowledge" (includes rules for hybrid children, critical hit rules for Groin Attack and "Porno periodical for humanoids" treasure tables). Or "Nymphology. Blue Magic." (Mongoose Publishing, Encyclopaedia Arcane series). Invariably contains mix of Fetish supplements, Mix-and-Match Critters close-up supplements, things You Do NOT Want to Know (whoever you are) and lots of jokes.
 * The Book of Erotic Fantasy actually has a friggin' TABLE for this kind of thing. Complete with cloud giants and 1" tall sprites interbreeding. Brain Bleach now, please?
 * Half-Dragon Shambling Mound. Half-Dragon Shambling Mound.
 * Of course, the true madness lies in the fact that successive halves technically do nothing to dilute the effect of each one... and the half-dragon template can be applied multiple times. Counting the half-dragon possibilities listed in the 'Draconomicon', it is possible (if impractical) to create a Half Amethyst, Half Battle, Half Beast, Half Black, Half Blue, Half Brass, Half Bronze, Half Chaos, Half Chiang Lung, Half Copper, Half Crystal, Half Deep, Half Emerald, Half Ethereal, Half Fang, Half Force, Half Gold, Half Green, Half Howling, Half Li Lung, Half Lung Wang, Half Oceanus, Half Pan Lung, Half Prismatic, Half Pyroclastic, Half Radiant, Half Red, Half Rust, Half Sapphire, Half Shadow, Half Shen Lung, Half Silver, Half Song, Half Styx, Half T’ien Lung, Half Tarterian, Half Topaz, Half Tun mi Long, Half White, Half Yu Lung Dragon... Gelatinous Cube. So bad, it's awesome.
 * But the real kick is that you can have a half-dragon dragon. Pink dragons (half-white reds or half-red whites) are especially powerful, as the template changes natural cold/fire vulnerability into immunity.
 * An electrum dragon (half-gold, half-silver) would do the same deal... Except not be evil. And pink.
 * Humans also seem to be able to breed with many things as well. When a Half-X is a race and not a template, the "Half" is assumed to be human.
 * Mr. Welch, of "Things Mr. Welch Is No Longer Allowed to Do In An RPG" fame, apparently uses this to imply that elves are easy.
 * Green Ronin Sourcebook "Bastards and Bloodlines" contains guidelines for turning anything into a half-template. Yes, anything. The cover of this book features a half-illithid drow (with both exposed cleavage and a bare midriff). It includes the half-beholder template. The first three creatures in the book are the Alicorn (Elf/Unicorn), the Aellar (Elf/GIANT EAGLE) and the Blinkling (Halfling/BLINK DOG). It is a very strange book.
 * Forgotten Realms has a share of its own.
 * Speaking of dwarfs and elves, Myth Drannor was named so "In deference to a visionary elf of old who found the love in him to marry a dwarf". And yes, in Forgotten Realms dwarfs of both sexes have beards, elves of both sexes don't. This one isn't too hard to imagine; unimagining it is another question. Elaine Cunningham's take on this particular combination you may see here.
 * Of course, the experimentation justification can't be used for the Draegloth, a product of hot Drow priestess on Glabrezu action. What makes this one especially squicky is that Glabrezu are incapable of altering their appearance, meaning that someone had consensual sex with a hideous, giant, four-armed, pincered, dog-faced, unholy abomination of the universe. One of the Drizzt Do'Urden novels actually not-quite-shows this happening. In Menzoberranzan (at least) the 'valedictorian' of each class of priestesses is accorded this 'honour' as part of the graduation festivities; indeed, Drizzt's sister partook of this herself when she graduated (though thankfully without 'offspring'), and considers "It brought me power" to be justification enough - before, during, and after. Thoroughly Squicky, even though the 'action' takes place off-screen.
 * They're drow, the only people who find "more power" to be a more thorough justification than Tim Taylor.
 * And the War of the Spider Queen series finally proved that the presence of one Draegloth is all that needed to not only turn a bunch of bickering, scheming, backstabbing drow on a mission for the sake of Religion of Evil into a party of quirky, yet rather likeable characters, but also do the same for another half-demon and . There are bastards, and there are... bastards.
 * There's an entire House of Gold Elves who not merely played with this, but had crossbreeding program, so now it consists of Daemonfey (half-fiends) and Fey-ri (tieflings). Apparently, old elven villains could be "outbastarded" only in a literal sense... The survivors of House Dlardrageth are balor's daughter Sarya, her son from a vrock Ryvvik, and son of her brother and a marilith Xhalh. Three other clans of fey-ri joined them, though these apparently were less enthusiastic and mostly limited their interest to succubi and incubi.
 * "The Singing Sprite" inn (Secomber) is named after its founder's wife. Because she was a sprite (as in, 2' tall winged fairy) and habitually sang atop the tables. Granted, that guy, while human, was a wizard...
 * There's a half-dragon... half-remorhaz.
 * Traditionally (i.e., before 3rd Edition), humans, orcs, and ogres were all interfertile. Humans mating with either always produced half-orcs or half-ogres (who were themselves fertile with each other and all three species), but orc/ogre pairings had it differently: A female orc mating with a male ogre would produce an "orog", basically a large orc that's smarter than either of its parents, while a female ogre mating with a male orc would produce an "ogrillon", a small ogre that's less intelligent than both parents and is inexplicably covered in bony nodules that give it an armor bonus; orogs are fertile but ogrillons are not. They dropped these complicated ideas in 3E and made no mention at all of orc/ogre hybrids, but orogs did return in Forgotten Realms as simply a large subspecies of the main orc race.
 * Even more confusingly, an orog in Birthright was just the setting's equivalent of an orc.
 * All that was probably the reason for doing away with half-breed templates in 4e. Wizards of the Coast parodied the template system with a fake leaked 4e Character Sheet on April 1st in 2008 with the race entry containing "Half-.../Half-.../Half-...".
 * Averted in the Old World of Darkness game lines, which actually had rather extensive FAQs in some of the supplementary books about what happened if various supernatural monsters got it on. Their solution? While most everything was human enough to mate, the powers you got were a spiritual rather than genetic thing, and the rules of spiritual inheritance were such that you could not have a "mixed soul". The result tended to be that the offspring would be one kind of monster without any real bennies from the other parent. (The writers of those books really hated mummified Vampire/Werewolves with Changeling powers and Mage spells, and went out of their way to keep them out of the game), although such "crossbreeding power" was hinted at in earlier editions.
 * The New World of Darkness has a hard-and-fast rule that no character may ever have more than one supernatural template, with various minor plot justifications to avoid questions being raised. (For example, werewolves cannot be possessed by spirits because of their own innate spiritual nature; in rules terms, they're immune because spirit possession is a different template.) There are "lesser templates" (psychic, thaumaturge, ghoul) a person can adopt while still being technically considered "mortal," but if they ever make the full upgrade to a supernatural, said template vanishes.
 * The Munchkin card game gives us the Half-Breed card, for Half Anything Hybrids. Elf/dwarf? Fine. Elf/gnome? Fine. Orc/dwarf? Fine. This moves into the seriously disturbing when the Dungeon of Ridiculous Races (letting you have as many races as you can find) kicks in; how does being half-elf, half-orc, half-gnome, half-dwarf, and half-halfling (quarterling?) sound? Arguably even worse are the 1/3-Breed and Chimera cards in the seventh expansion; 1/3-Breed lets you have three races, while Chimera means two or more races at all times, with the card being lost if you go below this. Whimper.
 * In Shadowrun, the standard fantasy races (elf, dwarf, orc (spelled ork), and troll) are explicitly said to be human subspecies. Interbreeding is possible in any combination, but children always match one of their parents (or sometimes revert to human); there are no mixtures. There is flavor text to the effect that a dwarf carrying a troll fetus would probably need major medical assistance to complete the pregnancy.
 * The prequel game Earthdawn added several decidedly non-human playable species, with interbreeding specifically labeled impossible (short of A Wizard Did It).
 * Given that (barring certain Charms) the only way for Lunar Exalted to produce beastmen is to either have sex with a human while in animal form or sex with an animal in human form, this has probably come up at least once.
 * There are implications that Luna and Gaia may involve this. Between the fact that Luna can shapeshift into all manner of forms (some of them truly colossal) and the suggestion that Luna only really gets fulfillment out of their relationship when Gaia's main bodies (some of which can be the size of planets) are around...
 * And then of course there is

Video Games
"Oh, and to those wondering: Hankosha + Feebas female (both Dragon egg group) = Feebas male + Marill female (both Water 1 egg group) = Marill male + Minun female (both Fairy egg group) = Hankosha. You're welcome."
 * In Pokémon, the 649 Pocket Monsters are divided into 15 "egg groups" based loosely on biological niches, such as "Bug," "Mineral," or "Fairy." Almost all Pokémon belong to at least one grouping; male and female monsters that share a group can breed, regardless of relative size or form, and the only Pokémon not in an egg group are "baby" Pokémon, most legendary Pokémon, and three others, two of which (Nidorina and Nidoqueen) seem to be only due to a bug that was maintained for the sake of continuity, with the last being Unown. The resulting baby will normally be of the mother's species, but may inherit moves from the father. The shapeshifting Pokémon Ditto is a special case, as it has no gender but it can breed with anyone to produce a new baby of the other Pokémon, allowing you to (for instance) get eggs from non-gendered or male-only Pokémon.
 * Especially odd are the kind of pairings one needs for some of the more complicated breeding chains. One chain for Ursaring (a bear) includes Heracross (a giant bug), Paras (an insect with a mushroom on its back), Chikorita (a stubby little green sauropod with a leaf growing out of its head), and Rhyhorn (a rhinoceros with rock armor plates). And, of course, you can have as the final pairing Teddiursa (which, as the name suggests, is a cute little teddy bear) and Rhydon (a huge bipedal rhino).
 * Also, this image.
 * The Let's Play of Mystery Dungeon mentioned above also lampshaded cross-chain breeding explained above. After Jake and Sheldon rescue a Plusle and Minun pair (the latter named Hankosha) and rescuing a Magikarp (who is also named Hankosha), the Magikarp explained the Minun is his great grandson. The author then added:


 * The early Dragon Quest Monsters games are the lords of this trope. While monsters are grouped into families based on type, any matchup will succeed as long as the prospective parents are of opposite genders. Dragons and birds, undead and plants, slimes and animated objects, and the offspring will nearly always be something other than either of its parents. On top of that, the child will have the potential to learn all powers of its species, all powers of both parents' species, and any powers either parent knew at the time of conception, allowing for some truly evil twinking.
 * The latest entry in the series, Dragon Quest Monsters: Joker, seems to solve the problem. Instead of each monster being male or female, they can be Positive, Negative, or Neutral, and the process is known as Synthesis. Synthesis requires a positive and negative monster, with a neutral monster substitutable for both (However, you CANNOT synthesize two neutral monsters.) Imagine the two monsters you pick being pureed in a blender, then having the concoction froze into a new monster. This could explain why you lose your monsters after synthesis.
 * In The Elder Scrolls, there are multiple sub-breeds of the cat-like Khajiit, with the phases of the moons determining which one they will become. At birth they're almost indistinguishable from plain old regular kittens but what they will become as adults becomes obvious fairly quickly. They range from being house cat shaped and sized, to roughly humanoid, to tiger-likes larger than a horse. They're all still the same species, and can all breed and give birth to any of them.
 * In-game texts Hand Wave unions of different species, with the offspring generally being based off of the race of the mother, though traits from the father can easily be inherited. Bretons (magically-inclined humans), for example, are the result of extensive interbreeding between ancestral elves and their human concubines until the hybrid population eventually crowded the two parent races out of the region.
 * Oblivion even has a character who was the son of an orc and a vampire. The result is a non-vampiric, but very pale Orc.
 * In Morrowind there is an in-game text titled Interspecies Phylogeny which treats the subject from a scholarly standpoint.
 * And let's not forget Ahnassi, though the relationship is only implied.
 * There's also an in-game text titled The Lusty Argonian Maid which treats the subject from a ... different ... standpoint. (Argonians are humanoid amphibians.)
 * And in the original The Real Barenziah in Daggerfall, it had (very NSFW) scene with a Khajiit and a Dark Elf
 * Morrowind also has an easily missable throw-away line hinting at this trope: there's a town with a strip club/brothel in it, and if you play as a male Khajiit one of the ladies working there will say something like "Not another Khajiit. I'm still smarting from the last one." If you've read the above-mentioned NSFW version of The Real Barenziah, or know much about cat anatomy, you can put two and two together.
 * Terra from Final Fantasy VI is a half-human, half-Esper hybrid. Madeline (Madonna in the SNES version) is an ordinary human female who wandered into the Esper World by accident; Maduin is an enormous Gigas/satyr-like Esper who barely looks humanoid. The narrative does away with the particulars by having the same-sized sprites perform a sparkly dance, at the end of which their sparks join together in the shape of a baby. Awww.
 * Acquiring colored chocobos in Final Fantasy VII requires you to breed chocobos you've captured and leveled up. Despite the squickiness, breeding their children, this a mild example and pretty much what people do in real life. VG Cats examined this in its usual manner.
 * And 8-bit Theater made it a minor subplot of more than a week's worth of comics, showing what happens when you try to play God (and happen to be more or less insane).
 * This is also pretty much how real specialized breeding works. There's a good reason purebred dogs have so many genetic disorders...
 * Forget Chocobos; Hojo tries to breed Aerith and Red XIII together! HSOWA and Mate or Die in one scene!
 * The monsters of Jade Cocoon can be merged with one another, creating an interesting Biological Mashup.
 * Demons in the Shin Megami Tensei games can be fused with one another, or in some games simply sacrificed, to create new demons. As demons don't gain power through play, unlike the human characters, this is the only alternative to negotiating with more powerful creatures.
 * As in the Dragon Quest Monsters example, however, both of the "parent" demons are lost and end up as a part of the resulting demon, who may or may not (depending on the game) end up inheriting bonus stats and/or skills.
 * Averted two separate ways in Persona: In the first and second ones (Persona 2 is a dualogy), you simply acquire "cards" (small fragments of energy) from demons, which you then make into Personas. In the third and fourth, the "Personas" are just shards of your personality, not independent lifeforms.
 * Sonic Adventure and its sequel both include Chao gardens. Chao may be trained and any two may be crossed, with the usual Lamarckian mechanics coming into play. This doesn't affect anything outside of the garden, though.
 * In those versions of the Sonic storyline based on the Saturday morning cartoon continuity, Sonic's girlfriend is the half-squirrel, half-chipmunk Sally Acorn. There have been a fair number of "future" scenes where the two of them are married and have kids.
 * The piñatas of Viva Pinata could be bred (I'm sorry, romanced) to produce offspring - this was a key point of the game. In most instances, piñatas were uninterested in those outside their own species, which avoided such "Skitty and Wailord" moments, but in one instance apparently-unlikely cross-species breeding could occur. The swan piñata Swanana and the pig piñata Rashberry could have hybrid offspring when certain requirements were met, producing the winged pig Pigxie. Which the parent species were apparently so ashamed of that they'd start fights with it. Even the in-game encyclopedia refers to this offspring as a horrible mistake. Unfortunately, there were only a few clues in the game as to how to breed this hybrid piñata, leading to another instance of Guide Dang It to figure out how.
 * Some of the requirements for the Swanana, which include building it a house, setting up a fountain, and giving it an expensive necklace, led to the remark, "The things I have to do for a pig's trophy wife."
 * In the NiGHTS Into Dreams series of games Nightopians and Nightmarens, two completely different species, can create an unholy Mepian hybrid. Try not to think about it too much.
 * Related to World of Darkness's aversion to this trope, people in The Matrix Online have roleplayed Exiles which were a mess of hybridization, including a part vampire, part succubus, part Valkyrie mongrel. Might be justified since it's all code in a virtual world.
 * Half-Ogres from Arcanum: Of Steamworks and Magick Obscura, like the Top Ten example above, plays the size differences between the two races in a rather dark light... If the female's the human, at any rate. The pre-created Half-Ogre player character is described as the offspring of a human male and an ogress with 'exotic tastes'.
 * Speaking of exotic tastes, there's a brothel in the game which the player can visit. If you turn down the normal offerings, you can be introduced to Bella. A sheep.
 * Warcraft 'verse has Malorne the stag god falling in love with Elune, the night elven moon goddess. Their offspring Cenarius, a stag/elf demigod, was then raised by Ysera the dragon. Cenarius' son Zaetar then fell in love with the earth elemental princess Theradras, which led to the birth of the brutish centaur race.
 * In Baldur's Gate II: Throne of Bhaal, the god Bhaal is revealed to have had children with everything from chinchillas to dragons and giants in his attempt to cheat death. This ability seems to have been passed down to his offspring; his son Yaga-Shura, a fire giant, tries have a child with a human woman. Bear in mind that fire giants are 12 ft. tall and around 7000 lbs. A player character who isn't a dwarf (as no one romances them) can bear children with elves. Albeit, gnomes and half-orcs (with the official patch) are stuck to Aerie and Viconia, respectively and exclusively. And Viconia wont dally with an elf unlike the other potential romances.
 * One Asari in Mass Effect 2, a humanlike race which can mate with about anything, mentions a past relationship with an Elcor, an alien race that can be described as an intelligent flat-faced hippopotamus.
 * In 3, Liara's father (also Asari) had a child with a hanar, a jellyfish like alien. During Blasto, the titular hanar gets some action with an elcor.
 * A human/human example in Jak and Daxter: Krew, who is so ludicrously huge that he needs a hover chair to move around, managed to have a kid. The sheer mechanics of it are mind-boggling!
 * In Princess Maker 2, one of the potential suitors you can get is a dragon. Now, he can at least transform to human for, but the implications are still a little bit uncomfortable.
 * So... horrible!
 * The Parappa the Rapper universe is implied to work this way by Word of God, though the results haven't been hinted at...
 * God of War  Ouch
 * Still both Chronos and Rhea were reigning Titans/Gods prior to Zeus' times, the game doesn't go far as to say every God/Titan can attain human form and change in size at will, but assuming it follows some aspects quite close to old Greek Mythology texts, Chronos might have had a humanoid form to consummate with Rhea, the same as Rhea might have had a giant form to pack.
 * Mortal Kombat gives us the Shokan, a race of half-human/half-dragon hybrids.

Web Comics
"Amy: Back in prehistoric times, when we were little more than animals, a squirrel like me would only be prey to a wolf like you. But today, we're two different species, but we're also a couple, and I'm carrying our child. Kind of interesting, zoologically speaking. Thomas: Zoologically speaking, shouldn't this also be impossible? Amy: Well, that's why we have comic strips."
 * 8-Bit Theater recently had a "Hot Monster on Red Mage action" with the result, that Red Mage himself was turned into the monster's offspring. The monster, of course, was a lot taller than RM, so that it first looked more like it was trying to squeeze him, rather than to rape him. It was explained by the monster having a third gender to "impregnate" (or, better, transform) other species.
 * And the less said about the Hot Witch on Dragon-God-King Action that occurred earlier, the better. Notable for horrifying the protagonists, individuals who are most commonly horrifying others with their actions.
 * Lich, a animated skeleton, has an apparently human wife and his son Vilbert is a vampire. This is eventually called into question and it's mentioned it involved Mind Control at some point.
 * Averted in a couple of ways in 21st Century Fox with minor character Veronica, who is a vampire bat. It's stated she was in an internet relationship with Cecil, a giraffe, before the beginning of the series. She explains a few times that why a more physical relationship wouldn't be feasible. Later in the comic she gets in a relationship with another minor character, a mouse, and they discuss children opportunities...adoption or getting the father's genes transferred gene by gene to the mother's species.
 * Chainmail Bikini (now dead) had the Munchkin character Josh created that was one-third human, one-third Drow and one-third Ogre. The other players note that this is physically impossible, which Josh himself doesn't care about. So page #10 is called "Three's Company" and the last panel is a hilariously dubious image of how it'd "work".
 * Lampshaded in Dan and Mab's Furry Adventures in an exposition strip which mentions a dragon and an anthro-canine who got married and have two children. The author vociferously refuses to answer the inevitable question, though there's an obvious answer given that the one known dragon in the series, Pyroduck, has been passing himself as a humanoid being for most of the series.
 * The same kind of explanation is used for half-dragons in Drowtales: The Moonless Age, and various Tabletop Games settings.
 * Also in Dan and Mab's Furry Adventures, a character in the story is a Kangaroo Rat, and has several half-Kangaroo Rat sisters. The "half", however, is taken both ways, as his sisters are all Kangaroos. Their parents are a Kangaroo Rat and Kangaroo (see Marshmallow Hell for details).
 * In Jack, almost every character is an anthro, so crossbreeding is just expected to happen. Oddly, though, it seems not only mammals, but also amphibians, reptiles and insect anthros can crossbreed freely, and the parents features somewhat scramble in the offspring. The obvious result is that few of the "mortal" characters are totally "purebreed".
 * The "Case Of The Travelling Corpse" points out that most species prefer to breed/interact within their own species . Still, crossbreed families are pretty normal. The child of a mammal and an insect usually ends up looking cute, green and mostly non-insect, for example.
 * Given the backstory, this becomes more plausible as.
 * In Kevin and Kell, it seems that even being of the same taxonomic order or class is not necessary for successful cross-species matings. The fox/wolf cross (Rudy) almost seems ordinary when seen with the rabbit/wolf cross (Coney), the wolf/sheep cross (Corrie), the fennec fox/formerly human rabbit cross (Francis), or the tortoise/weasel cross (not named in the strip, to the best of this editor's recall).
 * Last Res0rt gets in on it too; the Celeste apparently consist of nothing BUT Hybrid Monster people who breed with all the other species within the comic to make more hybrids.
 * And then they add WINGS on top of all that.
 * Averted in Tally Road- after several sexual exploits that are plainly cross-species, the first time any sex with like-species individuals occurs, the guy's seen putting on a condom. Apparently cross-species pairings are infertile.
 * Averted to a degree in the Chip 'n Dale Rescue Rangers fancomic, Of Mice and Mayhem. During the prologue, Chip acknowledges his feelings for Gadget, but refuses to act on them, because he believes she will one day want to have children, which wouldn't be an option for them since he's a chipmunk and she's a mouse. This is later worked around, as a previous gene splice between Dale and Gadget left Gadget the ability to mate with chipmunks.
 * One The Order of the Stick comic showed the inherent Squick of family life as a half-orc, the joke being that, in D&D, half-orcs are considered a little bit squicky because they're implied to usually be the result of rape, while in the comic, the kid is squicked because.
 * They also contemplated the origin of the legendary Owlbear. When Elan suggested that an owl and a bear mated, Belkar expressed hope that the owl was the male in the relationship, as otherwise certain problems would surely arise.
 * #721 reveals Enor the bounty hunter to be a hybrid of a half-ogre and a dragon. As in, half dragon, one quarter human, and one quarter ogre.
 * The Ancient Black Dragon is related to at least three half-dragons, one of which seems to be a half-dragon centaur.
 * Yet Another Fantasy Gamer Comic has one instance where the lonely minotaur character decides to stay and live with the lonely gynosphinx character ten times his size. In his own words, "With magic, anything is possible." Though this was less about mating and more about companionship (and the Sphinx's gazongas being big enough that the minotaur could fit his whole body between them). Eventually the question is answered: sphinxes know magic, and she turns one of them into the other's species when they're feeling... affectionate.
 * And don't forget Gren (a goblin) and Bob (a Beholder), how does that even work? I don't wanna know
 * A sketch on the site shows their hypothetical offspring from a scrapped storyline wherein Gren would have a nightmare about her future children. It could charitably be described as Ugly Cute.
 * Sabrina Online has this in spades. Sabrina's boss is a skunk with stripes because her grandfather was a white tiger. Thomas is a part wolf, part fox hybrid. And when Amy becomes pregnant with his child...

"Hope the kid doesn't take after my side of the family, or you're in for a ride, girl!"
 * But if that wasn't disturbing enough already, Tom's lupine father drops this piece of advice for Amy:

"Coyote: What an interesting first union that must have been!"
 * There is also the side-character, Carly the Chinchilla, who also married a wolf much taller and broader than her.
 * And Sabrina recently started dating a raccoon.
 * VG Cats: And that's where the robot skeletons in Doom 3 came from!
 * In Gunnerkrigg Court a cross between  is apparently possible.

Web Original
"Elf Ranger: And what part of "naked chick standing on top of a dead dragon" didn't say major demon to you?! Human Bard: (lifted off the ground by a happy embrace of "chick" with hooves and spiked tail) uhm... the "naked chick" bit... ?"
 * The series of artwork (often NSFW) about adventurers by Fredrik K.T. Andersson (author of Pawn) includes a character best described as "Bard who knocks up every critter in creation". And is so much surprised by the results one may suspect he was drunk half-blind during those encounters. This one is safe-for-work, if potentially hurtful for a brain. Of all living beings he had troubles only with elves. Also, there's "Dragon and Succubus". Speaking of which--


 * Poster "Bloodlines. Answering the questions you never wanted asked.", possibly referring to "Bastards and Bloodlines" (see above).
 * The Team Fortress 2 fan video Spy and Pyro starts off as what seems like a TF2 parody of Looney Tunes, but then becomes a sex story between BLU Spy and RED Pyro. The video ends with Pyro giving birth to.

Western Animation
"Batgirl: What do you suppose they do on a date? Batman: ...I don't wanna think about it."
 * The Simpsons. One Halloween episode has Marge falling in love with a Paul Bunyan version of Homer. When Homer questions her about finally consummating their love, Marge states that she'll do it after she finishes taking yoga classes.
 * Batman the Animated Series: In "Love is a Croc," Baby Doll, an adult with the body of a child, falls in love with the easily seven-foot Killer Croc.

"Geldhemoor: I am a hunkeycorn -- half hummingbird, half donkey, half unicorn. Gandhi: A hummingbird and a donkey doing it? I hope your mom wasn't the hummingbird."
 * Ben 10 Alien Force introduces the Half-Human Hybrid Plumber kids; all of them being, well, alien hybrids. One of the first ones seen is half Pyronite, half human. Pyronites are beings made of magma, are constantly on fire, and live on a sun. The only mix that might be weirder would be a half Galvan (Greymatter), what with a Galvan being a six-inch tall, bug-eyed, grey alien...
 * Though the weirdest has to be Gwen. An energy being? How'd that work? One can only guess it was halfway between the standard fashion and magical creation.
 * Gwen is one relative removed from that lineage. Her father is the son of Max Tennyson and Verdona, her energy-being grandmother. As Verdona demonstrates, she can outright warp reality on a whim. Creating human organs was probably simple. The "spark", as she called it, carried on in her offspring from that point.
 * It gets weirder when you realise that said "spark" won't necceserily 'take'; Besides Verdona, Gwen is the only member of the family with Andonite powers, the rest (including Ben) being merely carriers. Gwen's powers, in essence, are the direct result of an STD (or rather, virus)...
 * Not only that, but Ben HSOWA's the entire High Breed race at one point, injecting DNA from all the other species of the universe into the High Breed.
 * It should be noted that interbreeding is primarily a human-on-alien thing, not an alien-on-alien thing. Apparently, it's one of humanity's greatest assets that it can take the best traits of other species and add them to its own gene pool.
 * Cat Dog comes close: A male frog and a sasquatch are the protagonists' parents... by adoption.
 * CatDog by themselves have to be a case of HSOWA.
 * An early episode of South Park about genetic engineering was named "An Elephant Makes Love to a Pig." Guess what happened.
 * Double example: the pig later had children, but the father was actually Mr. Garrison.
 * In the commentary, Trey and Matt revealed that the episode was originally going to be called "An Elephant Fucks a Pig", stating (paraphrased) "An elephant does not make love to a pig. They fuck."
 * The Grim Adventures of Billy and Mandy gives us the union of Irwin's parents, the father being a Dhampyr, the mother being a several-millenia-old mummy. In a fantastic moment of Getting Crap Past the Radar, Irwin's dad even says having a son is "leaving a lot of questions that don't need to be answered".
 * In the pilot for Squidbillies, Early Cuyler had romances with his morbidly obese human lover, Krystal, and while he was in prison, she was pregnant with Rusty, who, shortly after his birth, was abandoned in an empty chicken bucket to be raised by Early's sister Lil. 15 years later, Rusty finds Early working on a chain gang and they reunite.
 * A series of Tex Avery cartoons asserted that the car, home and farm "of tomorrow" would include crossbreeds of both living beings and inanimate objects-- corn crossed with Mexican jumping beans to make it hop into your mouth, etc.
 * Parodied in the SpongeBob SquarePants "Rock-A-Bye-Bivalve", a passerby notices Spongebob and Patrick walking a baby Scallop together, and tries to make sense of the apparent inter-species relationship.
 * Hot turtle-on-cat action in Rocko's Modern Life. And one of their offspring was a  cow  steer because a steer friend helped hatch the eggs, so one presumably took after him. Don't worry about it too much.
 * Lampshaded on Robot Chicken with the Wuzzles, hybrids of two different animals. A lion rapes a bee just to illustrate the point.
 * Gandhi's raisin trip on Clone High:

"Iceman: I can't marry you! You'll probably step on me!"
 * Not to mention that Geldhemoor later offered to lay Gandhi. Thrice.
 * The Cartoon Network original movie Firebreather has the main character Duncan, whose mother is a human and father is a massive Kaiju. It's Lampshaded in one scene when his mother tries to explain how its possible, only for him to refuse to listen.
 * In the Ren and Stimpy Adult Party Cartoon episode "Altruists" Stimpy puts on a female duck costume to make the guard duck fall in love with him, when they start making out Stimpy lays eggs with contain half cat and half duck creatures.
 * Carter thought Brian knocked up his prized greyhound. When the puppies were born, they looked amazingly like Ted Turner...
 * Brian did father a perfectly normal human child with Tracy.
 * In an episode of Spider-Man and His Amazing Friends, a frost giantess falls in love with Iceman and tries to make him marry her. She doesn't see anything unusual about this, but he's terrified.

Other
""Then why is her belly not distended with a squirming brood of grubspawn?" "Because I'm not from this planet! Our biochemistry is totally different! He'd have more chance trying to impregnate a native plant than he would me!" "And even that would be impossible! I used to do it with fruit all the time and nothing came of it!""
 * There's a trio of Mons-based web roleplaying games, unofficially known as the Hidden Crossroads, that use this trope. The first such site alows for any two creatures to breed via a special item; the results are Mix-and-Match Critters. The other two sites have several different types of Mons that can only be obtained via breeding, but they're all variants on the same species.
 * Pretty much all Half Human Hybrids in fiction if you think about it. We're talking about species that share no common ancestor, or at most a common ancestor billions of years back (in a panspermia universe). A human would probably have much more in common biologically with a mushroom than with an alien. Yet somehow you have examples of them mating and producing viable offspring. The mind boggles.
 * Spock, of course, being the most famous example. Given that two humans can have a problem if they are of blood types, say, A+ & B-, how the heck do beings with copper- and iron-based globin get anywhere? Though some material mentions it took some technical intervention.
 * This is mostly justified in that in one episode of TNG, the crew finds evidence that
 * Lampshaded in Gorgeous Princess Creamy Beamy:

"Cookie: Are you registered anywhere? Nate: Yeah, Home Depot. We could really use a ladder."
 * The online Flash incarnation of You Don't Know Jack had Nate the Intern Episode 60. No known offspring resulted, though.

""Dragons and virgins. Dragons. And virgins. The mechanics alone boggles the mind.""
 * On the Neopets website, there's even a book that lampshades the oddity of Neopian family lines, such as a Skeith and a Zafara having a Lupe, an Ixi, and a Gelert as their offspring.
 * Neo Quest II has this with pretty much every NPC that has children. For example, in a village in Chapter 3, one family is made up of an Acara (a cat/goat hybrid) father and a Wocky (fox) mother, who have children who are a Cybunny (rabbit) and an Uni (unicorn).
 * The Brobdingnagian Bards song Do Virgins Taste Better? wonders why dragons prefer kidnapping virgins to any other kind of person.

""I crossbred a hedgehog with an earthworm. The result was: One yard of barbed wire!" "Interesting. But I managed to cross a pig with a letterbox. The result: A piggybank!""
 * Two Mad Scientists talk about their latest experiments:


 * There is a joke about a man who crossed a cockroach with a watermelon - now, there is no bothering with getting the seeds out.
 * Then there's the guy who crossed a Blue Tit with an enormous pear tree, and was very disappointed to get an enormous pair of blue trees.
 * The wizards on Discworld never got very far in figuring out genetics, as their initial experiments in crossing garden peas and fruit flies only resulted in a green bean thing that buzzed.