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Dominant Species Genes

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In many settings, Interspecies Romance, when it can produce offspring, usually results in kids that combine traits from both parents, but sometimes one parent's species seems to be consistently dominant. In those cases the offspring is one parent's species or the other's, rather than a hybrid of the two.

Often how One Gender Races and Succubi and Incubi reproduce. Gender Equals Breed is a Sister Trope where the offspring inherit the species of their parent of the same sex (sons like fathers and daughters like mothers). Sub-Trope to Either/Or Offspring, where offspring only inherit one species, but neither species is consistently dominant — siblings can be of different species.

Compare Random Species Offspring.


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    Anime and Manga 
  • Beastars: Legoshi's mother was the child of a female grey wolf and a male Komodo dragon. As a child she could pass for a pure wolf but her hybrid traits started to manifest as she got older, which led to her committing suicide since she couldn't handle losing the ability to pass for normal. Legoshi is one quarter Komodo dragon and also can pass for a pure wolf, but is immune to Komodo venom and exposure to it activates his recessive Healing Factor.
  • Goblins from Goblin Slayer are a male-only One-Gender Race. When they rape a woman of another species, the child is always a goblin.
  • Monster Musume: Most monstergirls appear to be able to conceive offspring with human men, the resulting child will always belong to the mother's species. This is the default method of reproduction for Lamias, Harpies, and Arachnae, all of whom are a One-Gender Race and require human men to reproduce. Other types like Centaurs and Merfolk are also capable of reproducing with humans, and the offspring will always be the same as the monster parent (though Centaur men don't appear to have any interest in humans, being dim-witted muscleheads).
  • Goblins in Re:Monster are similar. Although females exist, goblin couples have a low conception rate, so they find it easier to breed with captured human women. The child is always a full goblin.

    Comic Books 
  • In Invincible, Viltrumites are a race of Human Aliens with Flying Brick powers that can interbreed with a wide variety of species but whose features are dominant. This is naturally imperceptible with humans, but a hybrid with an Insectoid Alien only has purple skin to show his mixed heritage, and even that fades as they age to a color within the average human range. In fact, it turns out Omni-Man's mission on Earth was to determine whether humans could be used to extend the viltrumites' diminished gene pool, and soften the planet up for invasion.

    Fan Works 
  • In My Brave Pony: Starfleet Magic, when a space pony has a child with an Equestrian, that child is always a space pony.
  • In Offspring, it's mentioned that half-Zora/half-Hylian or half-Rito/half-Hylian children always match the race of the mother.

    Film — Animation 
  • In Hotel Transylvania 2, Dracula's half-human grandson Dennis will either turn out a human or a vampire, with his fifth birthday as an apparent deadline to grow fangs if it's the latter. Ultimately, he turns out to be a vampire.

    Film — Live-Action 
  • Alien: When xenomorphs implant themselves into other species, the result is obviously a xenomorph (black skin, spiked tail, huge head, Nested Mouth) but it has slightly different characteristics depending on the species that was implanted (a dog gives a four-legged version instead of the usual type, a Predator has mandibles, etc.).

  • The Dresden Files:
    • White Court Vampires can breed with humans and always have half-vampire children even if both parents were vampires, since they are almost entirely human on the physical level. They change into full vampires when they kill a human by feeding for the first time, but if they haven't done so yet, they can also kill off their vampire side and become fully human by poisoning it with the emotion that harms it.
    • Changelings are the progeny of humans and fairies. They make a choice between becoming fully human or fully fairy and can make that choice at any time.
  • In Emergence, the offspring of a mating between a homo sapiens and a homo post hominem will always be a hominem. There are sapiens who are aware of this and really don't like it. Unfortunately, they have access to some really nasty ways to try to wipe out the hominem population.
  • In A History of Glitter and Blood, the child of a fairy is always a fairy, though showing some traits from its mother. Female fairies are always infertile.
  • In InCryptid, the finfolk are cross-fertile with humans. Children of finfolk mothers will always be finfolk, while children of human mothers may remain human, although they display the dementia in later years that is characteristic of the finfolk growth cycle.
  • When a Nephilim from The Mortal Instruments breeds with a human, the child will be a Nephilim.
  • Paradox:
    • Male Chatcaava can impregnate females of other species with Chatcaavan offspring due to their shapeshifting abilities. Later books reveal that female Chatcaava used to be able to assimilate traits from other species and pass them onto their offspring, but the Empire's new religion genetically engineered that ability away save for the rare atavistic females like the Slave Queen.
    • Most of the first- and second-generation Pelted can hybridize with each other, but in the "modern" day interracial couples usually genefix their kids to express one genotype or the other.
    • The Eldritch engineered themselves to have a dominant genotype to baseline humanity.
  • Kitsune mothers in "No Need for a Core?" almost always have kitsune children, though those children may also gain other traits. This is less reliable with kitsune fathers. Fae creatures tend to flip this, with their offspring being clearly part fae and with fae traits cropping up randomly even in distant descendants.
  • In The Shadow Over Innsmouth, human and Deep One hybrids are born looking human, but gradually become fishier as they get older until they become full-blown Deep Ones.
  • In Tolkien's Legendarium, people with mixed human and elven ancestry can, and sooner or later must, choose to be human (and therefore mortal) or elven (and immortal).note  The visible examples of this in The Hobbit and The Lord of the Rings are Elrond Half-Elvennote  and his daughter Arwen. Elrond chose to be an elf; Arwen chose to be human so she could live out her life with Aragorn.
  • Dryads in The Witcher have to breed with human or elf men and the child will always be a dryad. The children will very rarely have their father's features like hair or eyes.
  • Xanth: While most interspecies offspring tend to be Mix-and-Match Critters or voluntary shapeshifters who can swap between their parents' forms, all offspring of harpies will be harpies. Male harpies are very rare (there weren't any for much of the series), so female harpies "summon the stork" with any male vulture or human they can trap or lure into a love spring.

    Live-Action TV 
  • Doctor Who: In "Gridlock", we briefly meet a Catman and human female husband and wife, who have a litter of kitten offspring.
  • In Prey, homo dominant are able to interbreed with h. sapiens and their genes are, naturally, dominant.
  • In the Star Trek: Voyager episode "Lineage", half-Klingon B'Elanna is disappointed when her and Tom's baby is shown in utero to look as Klingon as her, despite being three-fourths Human. The Doctor mentions that Klingon traits tend to be dominant.

    Tabletop Games 
  • While Dungeons & Dragons tends towards Half-Human Hybrid, there are some cases.
    • Dragon magazine had an article on Hags which stated that they mate with human men, then eat them and place their human-looking daughters with human families until they turn into Hags at puberty.
    • An online article about the Eberron setting, where Half-Elves are an established race, stated that with humans their progeny had a fifty-fifty chance of being human or Half-Elf. But if a Half-Elf married a full Elf their kids would always be Half-Elves.
    • As of Fifth Edition, if an orc mates with a non-ogre non-orc it results in either a half-orc or a full-blooded orc.
    • Doppelgangers, a species that is generally too lazy to bother with parenting, usually reproduce by assuming the forms of attractive males of their preferred species and bedding women from that species before clearing off. The resulting offspring look like members of their mothers' species but are in fact doppelgangers who are basically mode locked until they hit puberty.
  • In Hc Svnt Dracones, Vector couplings produce Random Species Offspring, but the progeny of Vector and Cog couples take after the mother. After all, one type is gestated in a biological womb and the other is built by an internal manufacturing center.
  • In Kitsune: Of Foxes and Fools, Akira, Cori, and April all had human fathers, but they appear to be no different from the other Kitsune characters. While Sharmarali'snote  father was a dragon, and she's said to have chosen her fox side, she has the highest overall stats but due to prejudice from the Kitsune Elders she has to work harder to earn tails.

    Video Games 
  • Darkstalkers: It is mentioned that an offspring of a Cat Girl and a normal human is always a cat girl.
  • In the Dragon Age series, human-elf children are, for all intents and purposes, biologically human—which is a blessing for many of them, since half-elves are discriminated against by both humans (who generally view elves as a lowly species) and elves (who are heading towards extinction and thus shun any crossbreeding with humans, as it never results in elves being born). Word of God is that there is a very specific reason for this, and it has more to do with elves themselves than with humans (so this trope is inverted: it's the elven genes that are universally recessive). It's heavily implied that Alistair's mother was an elf Gray Warden, who had a one-night stand with King Maric, and then gave him the human-looking baby to raise.
  • The Elder Scrolls: Downplayed but extant throughout the series, to note:
    • This is the case for all mixed-race hybrids in the series, being Uneven Hybrids while averting All Genes Are Codominant. Throughout the series, several in-game books and backstory details indicate that each race of Men (Imperial, Breton, Redguard, Nord) and Mer ("Elves" - Altmer, Dunmer, Bosmer, Orsimer) can indeed interbreed, with the race of the offspring usually being virtually identical to the mother, with a few of the father's traits potentially sprinkled in.note  For example, if an Altmer father and Nord mother produce a child, it wouldn't be a Magic Knight combination of each race. Instead, the child would be almost entirely Nord with the potential of having some Altmeri traits, such as slight points to his ears, higher cheekbones, or a slightly different skin tone.
    • The Bretons are the most famous hybrid race in Tamriel. Their (human) ancestors were Breeding Slaves to the Direnni Altmer of High Rock. Over the course of many generations, some of the Elven traits started to come through with greater dominance. This has led the Bretons to be the most magically inclined race of Men in Tamriel at the cost of some of the Humans Are Warriors traits of the other races of Men. It still isn't accurate to call the Bretons "half human" hybrids, however. They are still almost entirely human with some Altmeri ancestry. It's noted that some elite noble Breton families still have slightly pointed ears.
    • The Bosmer are said to be result of ancient hybridization as well. When the Aldmer (Precursors to all of the modern Elven races) first settled in Valenwood, they started to take "Mannish wives," leading to the modern Bosmer. It is worth noting that out of all the races of Mer, the Bosmer are the ones who look closest to humans and have the most human-like skin tones. In the exact opposite of the Bretons, the Bosmer are still almost entirely Mer.
  • The Legend of Zelda: The Gerudo tribe consist entirely of women aside from the once-a-century man, so their fathers are universally Hylians. Yet there are no Gerudo who look part-Hylian in Ocarina of Time, only a small handful have lighter skin as would be expected in Breath of the Wild, and none consider themselves part-Hylian. Contrast this with Granté, who is half-Hylian, half-Sheikah and both looks and is explicitly identified as such.
  • In the Mass Effect series, asari are all "female" and reproduce by a form of parthenogenesis where they psychically link with another, preferably of another species, and rearrange half their genome to resemble their partner's. The children are always asari, of course, but they are said to have a father of a different species.
  • Unlike Real Life animals, gendered Pokémon species belong to one or more egg groups. That is, as long as two different Pokémon species share at least one of them, they will be able to breed regardless of their size, appearance and habitat (cf. Hot Skitty-on-Wailord Action). Oddly, the resulting hatchling will inherit its mother's species and its father's learnable moves, averting any Mix-and-Match Critters expectations.
  • In The Sims 3 and The Sims 4, Sims abducted by aliens and impregnated will always give birth to a 100% alien child, with alien powers and appearance. However, this is averted if and when the alien child has a child, they may or may not have alien powers and appearance. Also somewhat averted in The Sims 2, where Alien Abduction results in a Half-Human Hybrid that can have more or less alien features depending on the child (however, alien traits are still dominant).


    Web Original 
  • In the Chakona Space universe when chakats mate with older species of "taur"; such as Terran foxtaurs, wolftaurs, and non-hermaphroditic cattaurs, the cubs are always chakats with some of their other parents' coloration. But when chakats interbreed with either of the species derived from them, skunktaurs and stellar foxtaurs, offspring take after the mother, and given that they're all Hermaphrodites that could be either parent.
  • In Dragon Cave, in most cases, the offspring of two dragons will be one of the parents' species. Only a handful of specific pairings can produce hybrids, and even with those pairings, hybrids aren't guaranteed; they can still produce either one species or the other.
  • Friendship is Witchcraft plays this for laughs.
    • Fluttershy has a dragon for a father. When asked how she looks exactly like a pony in spite of her ancestry, her only explanation is "Dragon-ness is recessive."
    • Another pony, Francis Sparkle, was a Doorstop Baby. A Freeze-Frame Bonus in a flashback reveals that his biological mother was Raincloud, who was literally a rain cloud.
  • In Monster Girl Encyclopedia, monster-human pairings always produce another monster due to monsters being created by the Chief God to be inherently superior to humans. The same is true for monster-incubus pairings (incubi being human men who've been transformed by the demonic energy of monsters). However, the Demon Lord is hoping to change this and allow monsters to give birth to incubus offspring.
  • SCP Foundation has an example in the form of SCP-3288 ("The Aristocrats"), a Human Subspecies that has been around for a very long time, with a history of inbreeding and genetic tampering, resulting in horrifically powerful mutants. Sex between a regular human female and a male 3288 specimen will always result in another 3288 specimen. This is due to their blood being so mutated and altered that it literally dominates any other genes during the gestation process. This is invoked as part of the Aristocrats' goal of literally breeding humanity into extinction, so that they can become dominant over those they see as "weak". This, combined with their other trademarks (Eats Babies, reveling in bloodshed and murder, etc.), means they are extremely dangerous if not kept in check.

    Western Animation 
  • In The Cleveland Show, it's mentioned in passing that Tim the Bear's mother was actually a kangaroo, though there's nothing about him to indicate this.
  • In Family Guy, it's revealed that Brian (a talking dog) has a son with an ex-girlfriend; both of them are fully human.

    Real Life 
  • Astonishingly, Truth in Television for a freshwater fish called the Amazon molly (named after the mythical Amazonian warriors, not the location). As their name implies, they're an all-female One-Gender Race, but instead of reproducing without the need of a mate (as with most other all-female animal species), they reproduce with males of different, closely related molly species. Rather than producing hybrid offspring however, the DNA of the sperm does not enter the egg cell and merely triggers meiosis by just its presence, a process known as gynogenesis, thereby making the offspring a clone of the mother molly alone. Since the male doesn't pass on its genes, and how it has no apparent advantages over normal asexual or sexual reproduction, it's a mystery why it works for the molly.