Bizarre Alien Reproduction
Wuffles: You are misinterpreting what you saw, Pieter!Okay, you've got your Humanoid Aliens. But no matter what you do, they don't seem alien-y enough. So you add some Bizarre Alien Biology. What's the easiest way to do this? Sex! Guaranteed to appeal to somebody, and if done right, it can look like something other than just being a pervert or possibly Fanservice. It should be added that no matter how deviant it seems to us, Good People Have Good Sex and this counts as good sex, even if it is interspecies. Sometimes related to G-Rated Sex. May fall into Artistic License - Biology, if the reproductive method fails to generate enough offspring to maintain a population. Note for examples to not include anything related to cultural practices; we're limited to the biology of reproduction here. Put Non-Mammal Mammaries, Exotic Equipment, Mr. Seahorse, Face Full of Alien Wing Wong, and Chest Burster on their own pages, please. Supertrope of Bizarre Alien Sexes. Compare Bizarre Sexual Dimorphism.
Pieter: I saw the tentacles! I know what that means!
Wuffles: My reproductive organs are in my mouth! It doesn't work that way!
Pieter: I saw the tentacles! I know what that means!
Wuffles: My reproductive organs are in my mouth! It doesn't work that way!
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Anime and Manga
- The Twelve Kingdoms has a truly weird reproductive system involving marriage but apparently no sex: when you get married, a fruit called Ranka grows on a tree, and out of it pops your baby. What makes it far weirder is that sometimes the Ranka fruit gets blown across the sea and is implanted in a Japanese woman - this is how the central character of the anime, Youko Nakajima, would have been born, though she thought she was a normal Japanese girl until she was taken by force from her high school. In addition, royalty and other immortals can't marry - and since Nakajima becomes a queen, that includes her - and so they can't have children unless they were married before they become immortal. While it's established that they DO have sex it's apparently only done for fun, with no connection to the reproductive process at all.
- The X-Men have fought The Brood, a race of intelligent Captain Ersatzes of the creature from Alien. A human implanted with a Brood egg will eventually be physically (and mentally) transformed into a Brood member, and will retain any genetic-based abilities (e.g. mutant powers) the victim had.
- In Phil Foglio's Buck Godot: Zap Gun for Hire's "The Gallimaufry" storyline, a male alien Pog member named Qvakk states that he loved Oort, another male of his species/race, and was "gonna take him home, make lots of eggs".
- Transformers in IDW's Transformers comic have a truly bizarre reproductive cycle that doesn't even involve sex of any kind. There are "hot spots" on Cybertron and its moons where sparks form and are promptly "ignited" by an energy pulse from Vector Sigma, the life-giving core of Cybertron. Once the sparks are lit they are carefully removed from the ground and placed within the cybertronion's constructed body. This is referred to as "forging" and is the natural form of reproduction for them. They can also artificially reproduce through cold construction, which involves surgically removing a portion of a spark and using it to grow a new one that is promptly placed into a body. There was much bigotry towards cold constructed bots in Cybertron's old days (to the point of there being a cybertronion apartheid) as they were seen as blasphemy towards Primus but it's more or less died out after the Great War.
- This trope is also deconstructed; this form of reproduction is so bizarre and impractical that when the life-creating pulsewaves from Vector Sigma started dwindling to a stop, it put the cybertronion race in serious concern about the future of their existence. By the time of the comics all of the hot spots on Cybertron have stopped creating sparks (there are hot spots on some metrotitan-created colonies but it's not said if they're still working). This, alongside the Great War, has greatly reduced the cybertronion population, making them an endangered species in galactic terms.
- We later learn in More Than Meets The Eye that cold construction actually involves taking essence from the Matrix (an ancient artifact) and using it to grow sparks in a lab, making transformer biology even weirder.
- The G2 comics feature an Big Bad who wants to return Transformers to their original reproduction method of budding off of each other.
- Disturbingly enough, there is a lot of LOTR fanfic in which elves have bizarre reproductive anatomy. The women have tiny, tube-like tentacles, that suck the sperm out of the males - and it is compatible with human anatomy, making the fics fit seamlessly into the Tolkienverse. It also gives a somewhat disturbing explanation as to why there is no fertile male elf-female human couple known in the history of Middle Earth.
Films — Live-Action
- The Xenomorph lifecycle in Alien goes roughly as follows:
- Queen lays eggs
- Egg waits for host (Human, Predator, Dog Etc) to come by
- Egg hatches, facehugger crawls out, jumps on host's face.
- Facehugger hangs on to host's face for day or two, host unconscious, facehugger keeps Host alive but tightens tail around neck if attempt to remove facehugger is made.
- Facehugger lets go and promptly dies.
- Host acts normal for another day or two (may/may not be aware of pregnancy).
- Chestburster bursts out of chest, with some of host's DNA (eg; Chestburster from dog becomes quadripedal drone instead of bipedal drone).
- Chestburster quickly grows up into either Drone or Queen.
- If Queen, cycle starts again.
- Although not actually alien, the creatures from the Tremors series have a bizarre life cycle that qualifies for this trope. Eggs hatch into dog-sized "dirt dragons", which transform into bus-sized "Graboids"; multiple bear-sized "shriekers" (each capable of rapid parthenogenesis) burst from the mature Graboid; mature shriekers pupate, then emerge as "ass-blasters", which lay eggs. It's unclear whether there's any actual sex required at all.
- In K-PAX, K-PAXians are known to have a very painful mating experience, "like having your nuts in a vice, but all over". The process also involves nausea and a terrible smell.
- Star Wars Expanded Universe:
- Khomites can only reproduce by cloning. They also only eat dietary supplements.
- And Selonians have one fertile female and a handful of males per 1,000 births. They're subterranean mammals; the queen and the males - presumably not from the same colony - basically do little but breed while the rest of the colony runs civilization. A little like naked mole rats. Humans and Selonians can apparently be allergic to each other. Or at least Corran and that one Selonian were.
- Falleen pheromones work on anything in the galaxy.
- And Dathomiri women can use the Force to arouse men and then you know the rest. Teneniel does this to Luke. While he doesn't like it, he still talks to her afterward.
- Zeltrons, Pink Skinned Space Babes that they are, have a sexual attraction to Force-sensitives. If there's one thing the Expanded Universe has driven home, it's that a lot of people have been attracted to Luke even before he married Mara - though for his part, he was politely disinterested in most of them.
- Yeerk are implied to have No Biological Sex, but have a form of sexual reproduction: three individuals fuse into one, which then disintegrates into hundreds of "grubs" which develop into baby Yeerks. (Occasionally one grub will turn into twins.) The Yeerk parents die in the process.
- The Skrit Na are even stranger. The "Skrit" look sort of like giant roaches and are fairly stupid. At some point during their lives they spin a cocoon, die, but then out of their dead body a Na (basically a Grey) pops out. It's never explained where new Skrit come from, but the Na certainly have a weird way of coming into this (or some other) world.
- From Everworld: male Hetwan, though usually little more than perfectly obedient drones for their deity Ka Anor, will immediately go nuts and mate with any female they see, which looks like a living collection of guts. A collection of eight to ten offspring are born immediately—-which is good, because the males rip the females to pieces while having sex.
- Though they can breed perfectly fine with humans, Martians in the Barsoom series lay eggs for some inexplicable reasonnote . Yes, even the Half Human Hybrids.
- Larry Niven's Known Space
- When asked, the Puppeteers say they have three sexes, but its not quite accurate. What they have is a "sperm depositor" male, an "egg depositor" male, and a non-sentient "female" (actually a different species that reproduces among themselves in a different way) called a "Bride". The Puppeteer ovum is deposited in the flesh of the Bride, the egg is then fertilized, and when the egg hatches, the infant puppeteer eats its way out of the body of the "female", like a digger wasp. In the Fleet of Worlds novels, it's revealed that this is invariably fatal to the Bride.
- Actually, pretty much all species in Known Space other than humans (and other hominids) and dolphins have a pretty thin time of it when it comes to sex. It's kind of Niven's trademark. It's likely that the Moties, who die if they don't get pregnant, were Niven's idea rather than Pournelle's.
- The hominids of Ringworld kind of make up for it by having robust interspecies sex a regular part of trade and politics.
- See also the Fuxes (below).
- The Doctor Who New Adventures novels suggest that Time Lords are all sterile and are "born" from a "Loom", a machine in their giant sentient semi-organic family Houses. Each Loom weaves Family members according to a common template, ensuring that they're related; every Family member is a genetically a cousin to each other.
- The Pequeninos of Speaker for the Dead, the sequel to Enders Game. To reproduce, the male has to be ritually vivisected to turn into a tree. Infant females are brought to the Fathertree and crawl around on its bark, absorbing sperm through its dust. Also: any female that survives to adulthood is completely sterile; the young eat their way out of the infant mother's body. Both male and female young are nursed in the Mothertree, which is what happens when a sterile adult female turns into a tree, which exudes a highly nutritious sap the young feed on until they're large enough to walk around on the ground.
In fact, all native life on the planet is like this (for example, there are no male herd animals—the grass they graze on fertilizes the females). They were changed by a virus, brought to their planet by other alien species. All species who didn't develop bizarre reproductive cycles died.
- Vonda N. McIntyre's Starfarer series has the squidmoths. The juveniles exchange gamete packets with each other and keep the packets they receive (the packets can stay fresh for a long time). At some point the juvenile consciously chooses to undergo a metamorphosis, consumes the collected gamete packets, lays fertile eggs, and dies.
- The alien city dwellers from Blind Lake have two stages in life. The sentient adult form is neuter and has a special feeding apparatus which the parasitic larval form require in order to survive. It's the larvae that actually do the breeding. On occasion, a larva is infected by the virus present in the adults and will transform into an adult itself.
- The mantis-like Ki! from Chess With A Dragon are hermaphroditic parasitoids, who implant eggs in "host-grubs" of various non-sentient species including feral human children they only think are dumb animals.
- One of the Star Trek: The Captain's Table books presented the Anjiri and the Nykkus, apparently two species of Reptilians whose gender (female, male, neuter) was determined by the temperature at which their eggs were incubated. Originally, they were presented in a fairly straightforward Planet of Hats way- the Anjiri were matriarchal, with the females running the planet and the males being basically incompetent Space Pirates; the Nykkus were initially presented as a sort of Henchmen Race to the Anjiri. It later turned out that the Nykkus and Anjiri are actually one species with two forms; females of either "species" in fact lay eggs for both, apparently regardless of whether their mates are Nykkus or Anjiri. All the Nykkus shown in the original appearance were "Coldborn" (neuter and not very bright); the male and female Nykkus shown later have little interest in working for the Anjiri, although the females are a lot better disposed towards them. Oh, and incubation temperature also determines, or at least strongly influences, both intelligence and physical strength (with females being the strongest/smartest for each race).
- The Phagors from the Helliconia trilogy have a cyclical libido, such that males are compelled to mate once every few days. They barely ever think about sex otherwise, yet the fact that such matings are conducted without any pretense of privacy, just as a human might sneeze in public, leads most humans to consider them lustful perverts.
- The life cycle of the Tyr in The Madness Season proves important to the plot of the book. Their homeworld has a century-long highly elliptical orbit. At the closest approach, the Raayat-Tyr, which serve as drones, return to the homeworld and fight each other through the hive in an attempt to reach the queen. A Raayat who mates with the queen will be killed. But, if the Raayat kills her, he will transform into the new queen.
- There is a lot of this is Piers Anthony's Cluster series; every species has a different, exotic way of breeding, and of course the hero, as he Body Surfs between the species, experiences them all.
- The Rozes, troll/giant hybrids from the Garrett, P.I. series, claim to be "triplets with different mothers". Garrett has never been inclined to ask for details, so we don't know if it's this trope or a cultural thing.
- Medea: Harlan's World was a collaboration between a number of major SF writers to create a single setting, and a series of short stories set on the titular moon. In Flare Time by Larry Niven, the reproductive cycle of the native sentients known as fuxes is described. They start off as six-legged females. At around seven they have their first litter, during which their rear body segment tears off, leaving them as four-legged females. The hindquarters contain the eggs, and function as a nest which the newborns eat their way out of. Around seventeen they have a second litter, leaving them as two-legged males, with the male organs exposed through the loss of the second body segment. The male guards the nest until the young are born, then goes into heat for about three years, and eventually ends up a 'post-male'.
- Between their advanced knowledge of the universe, their shape-shifting nature and the wide-range of powers they are able to borrow from each other, the Gods and Demons of Divine Blood are capable of this even if it's not their normal choice. They are canonically capable of:
- Homosexual Reproduction
- Creating homonculi out of two or more genetic samples.
- Nonsexually inducing pregnancy (willing or otherwise).
- Mr. Seahorse
- And they also accept Transhuman recruits into their ranks. Lilitu Geisthexe notes that former humans outnumber Immortals with both God and Demon heritage.
- The mental patient "prot" from the novel series K-PAX describes the K-PAXians' mating process as being extremely unpleasant, involving profound pain, nausea and a potent terrible smell. The books tie this in with a kind of Immortal Procreation Clause — since the K-PAXian lifespan is over a thousand years, combined with the unappealing mating process, there's no problem with either under OR overpopulation.
- The Lo'ona Aeo in Mikhail Akhmanov's Arrivals from the Dark series have four sexes. Their approximate names are male, female, half-male, and half-female. Half-females are sterile and don't participate in the reproductive process. Males and half-males join their minds with females, which starts the "mental contamination" process and impregnates the female without actual physical contact. The resulting child's personality is based on all three parents. Until their maturity, Lo'ona Aeo can artificially induce a slightly different sex on themselves using medical means (e.g. an immature half-female can make herself a female). Reproduction is directed by the heads of extended families in order to prevent unwanted genetic branches. Thus, they may force a female to become a half-female in order to cut off any possible offspring from that line.
The novels describe a unique case of a human male (descended from a human-Faata hybrid) using his latent telepathic abilities to accidentally "mentally contaminate" a Lo'ona Aeo female. Her son ended up lacking the extreme xenophobia that all Lo'ona Aeo have and becomes an adventurer (a quality inherited from his father). Since Lo'ona Aeo live for over 1000 years, he has encountered several of his father's human descendants.
- The Stormlight Archive. Little is known about the reproductive process of the Rosharan chasmfiend, but one stage seems to involve the creature climbing up onto a plateau, spinning a vaguely insect-like cocoon out of what is basically cement, and waiting for one of the storms that come along every few days. Presumably, they need the Mana the storms carry to fuel the transformation to the next stage of their cycle.
- The Hosts in Embassytown have a cycle that's skimmed over, but there is an initial aquatic phase of life, where the young Hosts are referred to a "elvers", a terrestrial phase where young play and fight, middle age and sapience, and their final phase, lumbering and nonsentient. They evolved to reach that phase and wander mindlessly after younger Hosts who at the time would eat them, but modern civilized Hosts, with no need of that, abhor the idea and treat elders kindly until they drop.
- The Color Of Distance's Tendu hatch in great numbers as tadpoles or narey. Eventually they metamorphize into froglike tinka, and live in the forests for a time until going into a village and acting as servants. Some tinka are chosen and treated to transform into bami, able to speak and reason and somewhere between children and apprentices. Bami, when those they were chosen by die or are exiled, are transformed again into sexually mature elders. Rarely elders will choose to become enkar, but this last stage is more a cultural than physical change. All levels eat some of the plentiful fertilized eggs and narey, and few tinka are chosen so that most die of animal attacks or old age, in order to help keep populations down.
- Since Starfish Aliens in Star Carrier are the rule not the exception, it stands to reason that this trope is played straight most of the time. The described examples include the Agletsch and the Grdoch:
- The Agletsch appear to be Insectoid Aliens but are not. The spider-like individuals are all female. Their males are small non-sentient grubs that the females keep attached to them at all times. When the time comes, the males fertilize the females.
- The Grdoch look like large balls with senses and mouths all around. Each Grdoch acts as both parents, fertilizing itself. The young are born inside and stay there until they sense distress in their parent, at which point they pop out and try to get away. The Grdoch lack any paternal feelings towards their young and frequently used them to distract larger predators or even as a light snack. In space, small, chaotically bouncing shapes can prove to be a hazard on any ship, but the Grdoch haven't found any way of preventing that, especially during battles, where the stress causes such "births".
- The main alien race in Greg Egan's Orthogonal trilogy is a gold mine for this trope.
- Sex immediately induces reproduction; there is no gestation period.
- Sex consists of two of the Shapeshifting aliens melding the flesh of their chests, through which the male transmits a light-based signal into the female's body to induce the reproductive process. No actual matter or bodily substance is exchanged; genetic diversity is ensured through the infrared transmission of "influences" by every individual to everyone around them — which, incidentally, is also how diseases spread.
- Females reproduce by splitting into four children; two sets of male-female twins respectively referred to as cos, who are genetically ideal mates for each other. The children who are not cos to each other are referred to as brothers and sisters, but the same terms are generally not used to refer to cos, probably to avoid implying that the relationship between cos is Brother-Sister Incest.
- In the rare event that a woman is born without a co note or is otherwise unable or unwilling to mate with her co, she can instead reproduce with another willing male, known as a co-stead. These relationships are treated more as a husband/wife relationship than the relationship between cos. It's considered a kind of reproductive Undesirable Prize, generally resorted to only when one co is dead or nonexistant, but there are occasional exceptions.
- Under the right circumstances, primarily old age or spending too much time away from their co or co-stead, spontaneous reproduction is common enough to necessitate women taking a drug to prevent it.
- In The Eternal Flame, things get even Weirder Than Usual: A woman fasting to the point of near-starvation helps to both stave off spontaneous reproduction as well as to ensure that, when it happens, it will result in only one pair of cos instead of two, for Population Control.
- And even weirder note : Near the end of The Eternal Flame, the biologist half of the Ensemble Cast develops a way to induce childbirth that produces only one child, does not kill the mother, renders her sterile for the purposes of traditional (fission) childbirth, and is shown to be repeatable in the final book, and can produce male children. In other words, they can more or less reproduce just like us.
- The Nac Mac Feegle in Discworld has one female to a tribe, who is the Kelda and is married to the most powerful warrior. It's her job to do the thinking for the entire tribe and, although she's their ruler, she's also, in a way, a prisoner. Female births are very rare and girls are expected, upon reaching adulthood, to either find a tribe whose Kelda has recently died or collect a few men from nearby tribes to form a new tribe. In either case, she takes some of her brothers with her to keep her company until she gets to know her new people. Incidentally, Terry Pratchett was quite interested in bees and their swarming behaviours.
- Star Trek has plenty of examples, having been on TV for so long:
- The Vulcans have "Pon farr", a mating season every seven years, where the male must mate or he'll die. Alternatively he can beat another male to death, which is just plain weird.
- Xyrillian females can impregnate human males without the human noticing.
- The Q can choose to have sex by touching fingertips, but being nigh-omnipotent that's not saying a whole lot we don't already know from the "omnipotent" label.
- The Varro mate for life, and to ensure this they intermix their body chemistry, causing symptoms of physical withdrawal if a mate leaves.
- All we know about Klingon sex is that it's not uncommon for both partners to break bones. Ow. A broken collarbone on the wedding night is a sign of good luck. Of course, given how Klingons tend to act, that might simply be a cultural tendency towards very rough sex.
- 90% of Taresians are born female. They claim to reproduce by implanting embryos in the wombs of females of other species, but the child will be fully Tersian. The truth is even weirder: They spread a retrovirus that turns males of other species into pseudo-Teresians, and then he's driven to return to the planet where they'll extract his DNA, fatally.
- Female Ocampa go through "Elogium", a puberty-like stage where they can successfully conceive a child (in a growth on their back), but it only happens once. Also leads to a very large bit of Fridge Logic, every Ocampa female can only conceive once, and multiples births seem to be rare to non-existent... so if every female Ocampa can only produce one child in their entire life... how is the species not extinct already? The Fridge Logic factor of Ocampan reproduction goes far further than that: Despite only being able to reproduce once and only living for nine years, the females have constantly engorged breasts. The reason why humans have breasts and dogs don't is because we can reproduce whenever we feel like it - there is no biological reason why they should grow breasts a good four years before they can conceive. Secondly, they reproduce through a bizarre system of massaging feet and gluing their hands together for an entire week using a thick, sticky mucus - in the wild no creature could do this without being eaten by predators. This would logically mean both the males and females have nothing between their legs and are around about the same size - if this was real life and not being played by human actors and actresses the only way to determine a male from a female would be those anomalous breasts.
- The J'naii are supposed to be genderless (although they all look similar to female humans). However, nothing about J'naii reproduction makes any sense, as the script muddles together three totally different kinds of genderlessness. The asexual cast to their society would make sense if they reproduced by cloning, but they do reproduce sexually, in which case being a One-Gender Race should make their interactions more sexual, not less. The persecution of those who prefer a gender would make sense for a race of hermaphrodites (where everyone is both sexes simultaneously) but their sex act is described as a precisely symmetrical affair (i.e. the J'naii are all one single sex—they're isogametes.) An isogamete preferring one sex over another makes about as much sense as a Cyclops preferring one eye over another.
- Denobulans have a mating season, and their breeding drive is regulated by powerful pheromones generated by their females. Males can become violent under these pheromones' influences. Culturally, they practice group marriage, and also remain promiscuous outside such formal relationships.
- The Kobali resurrect, and genetically alter, the corpses of other species.
- Andorians, as revealed in the expanded universe, have four separate genders, all of which are needed for reproduction. Deconstructed in that this is revealed to be causing their genetic diversity to break down; by the time period covered in Star Trek: Deep Space Nine Relaunch, they're a Dying Race with extinction predicted within fifteen generations. And that is being optimistic. There is actually a scientific movement underway looking to retro-engineer them back into being a two-gender race, which is meeting severe opposition from many Andorians, as the four-gender quartet is an integral part of their culture and religion.
- Babylon 5's Centauri have six prehensile tentacles for sexual organs, which are flexible enough to (as Londo demonstrated in a first year episode) snake under a poker table and pick up a card on the other side of the table. Centauri women have six corresponding slits on their backs. What drives this into Bizarre Alien Reproduction rather than it simply being Exotic Equipment is that the amount of pleasure from intercourse goes up for each tentacle/slit used, and use of all six is required for conception. One imagines that Centauri orgies are as decadent as their civilization as a whole...
- There's also the Pak'ma'ra, for whom the only reproductive information mentioned in-show is that the "hump" on their backs is actually their reproductive area. (According to Usenet postings by the creator, female Pak'ma'ra are tiny, non-sentient beings who live inside said hump.) Finally, in one episode Ivanova tricked one alien into believing that a strange dance (with nonsensical chanting)—which seem to be an abbreviated script for a one-night stand—and rubbing of hands was Bizarre Human Reproduction. At the end of the episode, Ivanova is left a gift by the alien: A trinket of some kind and a note saying "next time ... my way."
- In Alien Nation, three Newcomers are required to make a baby: a male, a female, and a binnaum who catalyzes the impregnated female. Part way through the pregnancy, the female transfers the fetus to the male, where it slips inside his belly somehow and attaches an umbilicus to one of the male's nipples. It is the pregnant male who gets to have the wacky Born in an Elevator scene at the end.
- In the original V miniseries, Willie recognizes Robin is pregnant because she's developing a ring of discoloration around her neck, which suggests that such rings are normal for Visitor mothers-to-be. His comments imply the ring becomes more complete as the pregnancy progresses.
- The 2009 remake is a little strange. The normal V reproduction involves a queen (like Anna) mating with a male, after which she eats him for nutrients. She then lays hundreds, if not thousands, of fertilized eggs with one or two being "queen" eggs. While initially thought impossible, it's discovered that Half-Human Hybrids are indeed a possibility but may be more V than human. Only one was shown onscreen, the product of a V father and human mother. However, the final episode shows a queen V mating with a human and taking a bite out of him, implying she has been impregnated.
- The Greys in The X-Files are capable of incubating inside a human host that has been infected with Black Oil. When the hosts gets hot enough, the alien hatches into a long-clawed, violent creature that desires more heat. Eventually, it sheds its skin to become a "normal" grey alien.
- Doctor Who: The Vespiform can mate with a human thanks to phase-shifting capabilities. Thanks to phase-shifting capabilities.
- In ''Andromeda the Magog reproduce asexually, laying their eggs in a host which then eats the host from the inside.
- SCP Foundation
- SCP-525 ("Eye Spiders"). SCP-525 looks like a small starfish. It climbs the body of its victim and extracts one of its eyes, then implants eggs in the eye socket. About 24 days later new SCP-525 hatch from the eggs.
- SCP-538 ("Shadow Spiders"). Shadow spiders reproduce by biting a victim. After about an hour the victim suffers a horrible death and their shadow breaks up into pieces. Each shadow piece becomes a new shadow spider.
- SCP-631 ("Nyctophobic Nocturnal Predator"). SCP-631 eats the internal organs of a sleeping human victim and lays its eggs in the body. When the eggs hatch an hour later the babies eat the body.
- SCP-632 ("A Bad Headache"). SCP-632 are small spiders that create a filament of spider silk and attach their eggs to it. When the filament touches warm skin the eggs hatch and burrow into the victim. When the baby spiders reach the brain they grow inside of it and cause a headache. The victim's attempts to stop the headache releases the adult SCP-632.
- SCP-695 ("Eels"). Juvenile SCP-695 perform a Orifice Invasion on a male human, grow to adult size and lay eggs. They then force the host to rape a female human and infect her with the eggs. The eggs will grow into juveniles, which will leave the female's body through either an Orifice Evacuation or performing a Chest Burster out of her abdomen.
- SCP-772 ("Giant Parasitoid Wasps"). SCP-772 implants 5-20 eggs into large mammals (such as human beings) using a barbed ovipositor up to 70 centimeters long. The eggs hatch 4-12 days later and the larvae start eating their way through the body.
- SCP-783 ("Baba Yaga's Cottage"). In Experiment Log 783, a cockchafer (beetle) was mutated so that when it bit into a person it implanted eggs into their body for later hatching.
- SCP-1092 ("A Species of Fish"). SCP-1092 reproduces by having one of its eggs enter the body of a large mammal through a cut and grow to adult size (up to 2.1 centimeters) inside the mammal's blood vessels.
- SCP-1294 ("The Laughing Fox"). SCP-1294 is a fungus that reproduces by mating with a female fox. Its offspring grows inside the fox and eventually escapes as a Chest Burster.
- SCP-1325 ("Easter Frog"). SCP-1325 are frogs that lays eggs that appear to be chocolate Easter eggs but have SCP-1325 eggs inside them. When they're eaten by human beings the SCP-1325 eggs hatch into tadpoles that attach themselves to the inside of the stomach and grow into more SCP-1325. When they're old enough they use a Chest Burster technique to get out.
- The Hitch Hikers Guide To The Galaxy
- We're never told the details, but the Betelgeusians Ford Prefect and Zaphod Beeblebrox in share three mothers (with the implication that Zaphod at least has more mothers who they don't share), which makes them "semi-cousins".
- Ford's father "both fathered and uncled" him, which could mean Ford is the product of incestuous relations, or just more of this trope.
- Dungeons & Dragons includes multiple examples, mostly among the Aberration creature type.
- Illithid Elder Brains (composed of the disembodied brains of dead illithids) asexually produce eggs in pools of water. The eggs hatch into tadpoles that cannibalize each other until the survivors reach maturity. Mature tadpoles are inserted into living adult humanoids to devour and replace the nervous system. This results in an adult illithid.
- Beholders also asexually reproduce. After becoming pregnant, they gorge themselves until the fetuses become too large and pinch the esophagus shut. When the children come to term, the parent vomits up its entire uterus (which does not regenerate).
- In Infernum, both the Legions of Hell and the spawn (Hell's equivalent of animals) have this.
- Spawn reproduce by dying; when you kill a spawn, multiple smaller, weaker spawn of the same kind will emerge from the corpse within a minute or two. Kill those, and even more spawn that are even smaller will emerge, ad infinitum, until the resultant spawn is too weak to "divide" in this fashion any more and simply dies upon death.
- Demons, meanwhile, reproduce through Spawning Pits... which manage to be even less fun than they sound like. Spawning Pits are filled with alchemical acids that dissolve living demons, but catalyse their organs, causing anywhere from one to thirty-six "larvae" to chew their way out of the decaying husk. After about six months, these maggot-like creatures pupate inside cocoons and then emerge as demons of the same kind as their "parent".
- Making things even more bizarre: demons and spawn are related to each other. The first demons were born when fallen angels had sex with spawn.
- Warhammer 40,000:
- Orks are partly fungus-based; they shed spores throughout their lives that can grow into any kind of Orkoid lifeform, and release a large number of spores upon death.
- Tyranid Genestealers implant genetic material in victims that causes them to form a cult-like devotion to the Genestealer and a drive to mate. Each generation spawned by the cult members will look less and less like a Genestealer until the fifth or sixth generation, which exactly resembles the host species. The next generation will then be "purestrain" Genestealers, and the cycle will start over.
- The fluff book Xenology hints that, while Eldar appear to procreate in the same manner as humans, males may have to make multiple deliveries of genetic material to fully conceive, as opposed to humans. The actual canonicity of this has never been established, though.
- Chaosium's supplement All the Worlds' Monsters Volume III. The Scarlet Stalker captures human beings and inserts eggs into their bodies. The eggs keep the humans paralyzed until the eggs hatch and the young eat their way out of the body.
- The Galka in Final Fantasy XI are an all-male race. They reproduce by "reincarnation", whatever that means.
- Mass Effect
- asari reproduction is based on 'melding'. During said process, the asari scrambles and changes up a DNA sample of her own, using the DNA of her partner, whatever sex and (sentient) species it may be, as a map/inspiration. The randomized version of the asari's genes is then combined with an unchanged sample of them for purposes of producing offspring. Sexual contact is not required, but not uncommon. Even more weirdly, mating within their own species is discouraged in order to avoid certain extremely nasty genetic defects that can occur from such a union.
- Much more disturbing with the Reapers, which melt down an entire sentient species into some sort of goo, which they mold into a new Reaper.
- Salarian females lay eggs throughout their lives, several a year. Fertilized eggs hatch as females, unfertilized ones as males. In order to keep from overwhelming their worlds, salarians only fertilize 10% of their eggs, using extremely complicated reproductive contracts to arrange who does what.
- In Patapon, you create new individuals by burying certain materials under a special tree.
- In an old Maxis game, Unnatural Selection, genetically engineered creatures reproduce via "melting into a skin colored blob, combinating and laying a baby version of themselves" you can watch this here.
- Pikmin. The tiny Pikmin apparently reproduce by bringing plant matter and insect corpses back to their hives/'onions', which spits out seeds that first plant themselves into the ground, mature for a while, and then get uprooted as new baby Pikmin. It is also possible that they require another creature (such as the player) to uproot them in order to enter their mobile phase and complete the cycle.
- Guilty Gear. While it's All In The Manual, Gears apparently lay eggs or the children come out in a protective cocoon they later hatch out of.
- One of Atrus's journals from the Myst games describe an other-Agely creature called a "ting", which seals itself in a rock crevice, from which a bunch of lizard-like "solastings" emerge a couple of months later. It's unstated how the solastings give rise to the next generation of tings.
- In Spore, Alien Animals dance together, then one of them lays an Easter egg (and then you can see if you have enough DNA stored up to tweak your critter for the next generation.)
- Chao from the Sonic Adventure series reproduce when one Chao sits in a bed of flowers and it joined by another Chao, the two proceeding to nuzzle until an egg containing attributes from the two appears. Most Chao enter this mating phase naturally with time, though it's possible to force mating to occur by feeding them a certain fruit,
- Dwarf Fortress
- It has been suggested that many of the species reproduce via spores rather than in the conventional fashion, given the way that you can chain up members of different sexes at opposite ends of the fortress and still get offspring.
- A more deliberate design choice can be seen in the form of night trolls, single gender monsters who kidnap members of the opposite sex, transforms them into "spouses", and proceed to reproduce in the normal way. The children are always the same sex as the night troll parent, and the spouse is often slain or simply abandoned (which inevitably means death at the hands of their former species). Notably, night trolls are happy to prey on elves, dwarves or humans, but goblins just don't do it for them.
- In the X-Universe the Teladi lay eggs that always hatch females if left unfertilized. For this reason space Teladi are effectively a One-Gender Race.
- Much like Xenomorphs, Chrysalids in X Com Enemy Unknown plant their seed into living hosts by viciously murdering them, which turns humans into shambling zombies. If a zombie is left alive for too long, it will burst into a newborn Chrysalid, identical in size to a "mature" one, but with lighter skin color.
- While it's never shown how sex among Pokémon works, some aspects of their reproduction are defintely weird:
- Every species is part of one or two egg-groups and could mate with any other pokémon of the same egg group as long as it's of the opposite gender. The offspring will always be of the females species, but with some of the males attacks.
- Ditto is genderless and could mate with any fertile Pokémon regardless of gender. The offspring is never Ditto, but always the other Pokémon's species.
- the only exception is Manaphy, which will always produce a Phione-Egg.
- Some species are male-only or female-only, with the male-only ones only possibilite to produce same-species offspring being Ditto
- the only exceptions being the Nidoran-line and Volbeat/Illumise, where male and female are regarded as different species, but the female can produce offspring of the male species, even if her male is of a different species.
- Some species are genderless and only able to mate with Ditto
- Some species cannot reproduce in-game, but some of them are seen to have eggs or babies in other media.
- Every species, even the mammal-based ones, lays eggs. But at least one species, Miltank, also gives milk.
- And the daycare-owner still doesn't know where the eggs come from. Some dialogue with NPCs even suggest that Pokémon eggs aren't even eggs in the biological sense and are more like "cradles"... Whatever that's supposed to mean.
- Uryuoms from El Goonish Shive have this in spades. They have one sex (but identify as male or female, meaning they do have genders). It normally takes two individuals to make an egg, made by secreting a certain substance - it takes two only due to the amount needed. Once the egg (which looks like a meteor) is formed, it lacks any DNA of its own. DNA of anything can be put in (through the openings that make it look like a meteor), and it will naturally create a new viable chimeric being inside it. Any number of sources can be used, (the current record is twelve). There need not even be an Uryuom as one of the genetic parents! Basically, they reproduce via a genetic engineer's wet dream.
- Trolls reproduce by "mixing genetic material"* with their lover and their archenemy in separate pails, and then giving the material to a drone. Gender is irrelevant to reproduction. All of the combined material is then basically mixed together, and a mother grub takes the best material and lays eggs for the whole species. As said in comic, Trolls sure are weird! The Fridge Horror of this comes from the fact that trolls arrive at sexual maturity around the same time as humans do, and are at the same level of emotional and mental security. These are kids put to work sexing it up the second they are capable of "producing genetic material", and they have no idea what the hell is going on.
- This has the side-effect of making pails (and pictures thereof) Not Safe for Work among trolls, as seen here* . This lead to a meme among Homestuck fans in which they react to any depiction of a pail or a bucket as extremely lewd and sexual, which in turn also makes this video completely unintentionally hilarious. The mind boggles at what they might make of the Lancre Stick-and-Bucket Dance.
- Universes themselves have a bizarre means of reproduction, which involves Stable Time Loops, a video game which manipulates reality and draws the players into the game, a war between anthropomorphic chess pieces which one side is always destined to lose, and sped-up frog breeding.
- Cherubs are even weirder than trolls. They can only mate with rivals, by a ritual where they typically go onto a black hole and turn into enormous, near-indestructable snakes that can only be harmed by one-another. Whoever loses the battle is impregnated with the young, and the Character Alignment of each child depends on which parent carries the young.
- Leprechauns are possibly weirder than cherubs, although we've been spared the details. Their bizarre alien romance involves combinations of nine emotions, one of which equates to human love or troll matespritship, and most of which involve pranks and riddles Unlike the four "quadrants" of troll romance, any of these relationships could lead to reproduction, following a "mating jig". Oh, and they seem to be a Single Gender Race.
- Sam Starfall from the comic Freefall is a Sqid. Only a small number of Sqid are fertile, and those breed early. Upon breeding, both the male and female die. A litter of young is born and, Sqids being scavengers, the Sqidlings have a ready-made food source. Other adults come along and pick Sqidlings to raise (a process described as being like picking a puppy). These "Mentors" raise the young Sqid in their race's ideals of chicanery and stealing everything not nailed down or on fire.
- Schlock Mercenary
- The title character is a carbosilicate amorph, essentially a race of organic data-storage systems turned sentient. They typically reproduce by splitting off a part of themselves that contains their personality, and merging it with that of another. On top of that, due to the "sentient data-storage" bit, it's also possible to reproduce with non-amorphs through a period of observation - a process Commander Kevyn compared to marriage. On top of that, two amorphs battling it out usually results in, rather than one or both parties dying, a single amorph with merged personality traits of both combatants.
- Also in this 'verse are the Qlavo, who conceive normally with males and females, but hand off responsibilities of development to a third gender, muftales.
- This goes on, as a whole rather more than we see.
- Allow Volaster Jarvoc explain to you how demons of Asgard reproduce in Heart Core:
"...a demon never truly dies...but they never truly reproduce either. It's rare, but when a demon decides to renounce their life, an egg with their reincarnation appears...This egg will also have attributes from another demon they've been in contact with. Within two years' time, the new demon will require the originator's Heartcore, effectively relieving them of duty."
- In Outsider the Umiak didn't use to apply for this. But nowadays they've biologically modified and twisted themselves so much that they might not even have any sort of natural reproduction cycle. Almost every Umiak seen is a clone of some sort.
- Kayoss in L's Empire reproduce by holding hands. Each Kayoss can only mate with one person, even if that person isn't a Kayoss, or in Void's case, alive.
- It's not what the exact process of reproduction is for aliens in Red vs. Blue, but in the end, somebody's going to get infected with an alien parasite and give birth. Even if they're male. And the alien in question is male too. It's like a miracle to see nature at work!
- The speculative alien species Triaformica has three sexes, but only needs two, each of a different sex, to reproduce. Sexual organ-wise, they're all hermaphrodites and the organs are in their chests, accessable via a normally airtight hole into which they stick their own tongue during mating to get their own set of sex cells. Then they stick their tongue into the hole of their partner while said partner is in heat to drop the cells into. The whole process takes about a minute and, while it feels 'nice' to them, it certainly isn't as pleasurable in the same way as humans.
- Kif from gets pregnant by touching someone. His species (Amphibiosans) become receptive to DNA transfer (impregnation) when they develop a strong emotional bond with someone, their smizmar. DNA is transferred through touch, and presumably any species' DNA is compatible. While in the episode in question the biological parentage gets mixed up, the smizmar is the "true" parent.
- Dr. Zoidberg's species lay eggs into the ocean and then die off en masse. He's only lived so long because no female seeking a mate will even look at him. This doesn't prevent Zoidberg having a Jewish Mother-equivalent relative, so presumably some Decapodians avoid mating to raise the kids.
- Futurama plays with this trope a bit by having aliens be unaware of human reproduction. Human noses are harvested as an aphrodisiac under the incorrect assumption that the "human horn" is the main reproductive organ. Lrrr is surprised to discover that humans have a "lower horn" hidden in their pants.
- There was an episode of the 90s X-Men cartoon where Rogue was almost turned into a Queen for the Brood, an alien race which breed by basically infecting other species and turning them into one of themselves. However, Rogue touched Wolverine, borrowing his Healing Factor and returned to normal.
- The French/Czech cartoon Fantastic Planet features the Draags. When the Draags wish to reproduce, they go into a meditative trance, which causes a spherical forcefield bubble to form around a small representation of themselves which then float up into the sky toward their planet's moon. Upon reaching the moon, they land on gigantic, headless Greco-Roman statues, which proceed to dance the waltz (no, really, that's all they do). In all fairness, that could have just been foreplay — the Oms (humans) did sort of start destroying the statues mid-dance. Also, despite the Draags exhibiting sexual dimorphism (there are Draags with breasts and ones without), all Draags form pink bubbles and land on the female statues. The male statues have blue bubbles which are stated as coming from some other species "from other galaxies". It's implied in one of the history lessons that there have been Draags for longer than there has been meditation, so the entire thing may really just be literally foreplay with aliens before they actually reproduce amongst themselves.
- The Transformers might count, with some overlap in "Bizarre Alien Assembly Process". Since Beast Wars they're usually depicted as metamorphosing from blank-faced liquid metal "protoforms," which depending on continuity may be grown in energy "wombs" and become fully grown cybertronians once they get sparks implanted. At least one series mentioned "protoform molds", which might be a jab at the old die-cast toys.
- In Steven Universe, as seen in "On the Run", Gems apparently manufacture new Gems using special machinery, with the new gems literally popping out of a hole in the ground. The Classroom Gems short "How Are Gems Made?" elaborates on this procedure: the Gems pop out fully grown, but the procedure also drains life from the soil and nearby plants and leaves the ground barren and withered.
- Many of the above scenarios were based on the life cycles of Real Life organisms.
- Ichneumon wasps implant eggs in host species, typically caterpillars. Hosts are also infected with a polydnavirus that suppresses their immune systems to protect the eggs. The larvae consume the least essential portions of the host's anatomy first, keeping it alive as long as possible. Once the larvae are mature, they emerge from the still living host and weave cocoons. Certain species produce mind-altering chemicals that causes the host caterpillar to guard and protect the cocoons until they hatch.
- Eusocial insects have a reproductive caste.
- In honeybees, sex is usually determined by males being haploid (one set of chromosomes) and females being diploid (two sets of chromosomes, like humans). Female larvae fed royal jelly become the reproductive "queen" caste.
- In termites, all castes are split between male and female but, depending on the needs of the hive, can change caste. If any of the queens or kings in a colony dies, another will change to take their place.
- Microorganisms physically merge when mating, in a process called bacterial conjugation.
- Plants alternate generations. In the case of flowering plants, the equivalent would be a human becoming pregnant, then having sex which fertilizes their fetus, and then the fetus gives birth to the offspring.
- A similar process can be seen in aphids, which alternate generations between parthenogenic females and sexual reproduction.
- Internal parasites, such as liver flukes, make all the above examples seem routine.
- The male anglerfish is tiny compared to the female. The sole purpose of the male in life is that once it gets the scent of a female, it swims to it and bites down on the side of the female. At the same time it excretes an enzyme at the mouth which causes it to physically fuse to the side of the female, and is functionally reduced to a pair of balls hanging from the side which the female can use to impregnate itself when it is most convenient. When anglerfish were first studied, the males were thought to be a completely different parasitic species.