Questions tagged [reproduction]
For questions about the means and methods any species, organism or entity uses to propagate itself.
263 questions
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What would cause species only distantly related and with vast morphological differences to still be able to interbreed?
In my books' universe, there are twelve sapient races, counting humans. They are all descended from a single species that was effectively identical to modern humans, but they have each adapted to the ...
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What are the pros and cons of this 3 gender/sex & pseudosexual reproduction system? [closed]
So I was revisiting this world I partially built a few years ago called Purpalis. In it I gave an Earthesque world some interesting modifications like the sky and water being purple, clouds being ...
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What share of the annual medieval birth rate need to be Cyclops in order to maintain the Cyclops population?
In my fantasy land, there are human males, human females, and Cyclops. Cyclops are all male. They are also larger, stronger, and hardier than human men. Cyclops reproduce with human women. The ...
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When half-elves have children their lives are drastically shortened. What's the formula for calculating it?
A human king had a daughter with an elven lady. The princess, half elf, half mortal, was blessed with a long life, but she was not immortal like her mother. When she grew up, the princess married a ...
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Why would sperm cells derived from women's stem cells always produce female children?
Lore Background
The Scientocractic Hivemind has defied the heavenly balance of the Equilibrium Hivemind, realizing that its transcendental nature makes this an inevitability. Determined to upend the ...
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Would human-shaped sperm cells work?
After looking at videos of sperm cells, they reminded me of someone swimming. I've decided this was a neat idea for me to integrate in my worldbuilding.
For lore reasons, I have a group of people with ...
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Long term viability of a human population with super healing that causes female to male sequential hermaphrotism [closed]
This question starts with a conversation I had with friends about the implications of super healing ability of Marvel comics characters like Wolverine, Deadpool, Hulk, and more. How would a person ...
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Can a species transition to ZW from XY (or vice versa) sex determination system through evolution?
In my world, there is a species descended from green iguanas (Iguana iguana) that has ZW sex chromosomes rather than XY like all other iguanids.
In the XY sex determination system (which is used by ...
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1
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How would replaceable egg yolk evolve?
Those familiar with Alex Ries' Birrin project probably know that the Birrin as an alien species have unique eggs with a sort of replaceable egg yolk the parent needs to exchange every so often. The ...
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Balancing demographic effects of different reproductive strategies [closed]
I am building a world with two sapient species, one of which is effectively equivalent to humans, and another one which has a series of differences. I would like to know how to tweak the numerical ...
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Is it possible to have a species where everyone is both male and female? [closed]
I'm trying to create a humanoid species where all members can both impregnate each other and carry children. Each member would be sort of interchangeably male and female, in the sense that they could ...
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Is it possible for an animal to have a plant stage in its life cycle? [duplicate]
I'm designing an alien species with a somewhat unique life cycle. When these aliens reach maturity, both males and females start producing thousands of tiny spores filled with hydrogen gas that float ...
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Which environment would favor sequential sexes as default? [closed]
A couple of years ago, I posted my idea of diachronic hermaphrodites as an answer. In brief, an alien or fantasy species of sentient humanoids goes through up to five phases in life: presexual kids, ...
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Can CRISPR technology be used to create ‘super soldiers’? [closed]
Can CRISPR technology be used to create ‘super soldiers’ that are animal human hybrids?
So the hearing of a bat, night vision of an owl, hunting prowess of a wolf, maybe resistant to pain and ...
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How would sex chromosome inheritance work in a tetraploid trioecious species with the ZW sex determination system?
I imagined a trioecious angiosperm species descended from common cocoa trees (Theobroma cacao). Trioecious = three sexes (male, female, and simultaneous hermaphrodite).
They use the ZW sex-...
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Can two species from the same genus but with a different sex determination system interbreed and have fertile (or at least sub-fertile) offspring?
In my futuristic world, there are two coelacanth species that are the daughter species from the famous West Indian Ocean coelacanth. One has the XY sex determination system (like humans, iguanas, ...
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Could cocoa trees evolve dioecy?
In real life, cocoa trees are famous for being hermaphroditic angiosperms from the Rosid class that are extremely bad at reproducing (they can be considered the giant panda of the plant world!). Also, ...
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Can human geniuses be cloned with modern technology?
In my story, there is a private institution called the GenoVate Initiative. The GenoVate Initiative wants to preserve the most exceptional individuals in the human gene pool. People who have ...
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How many members of a species would be required to prevent inbreeding? [duplicate]
I’m writing for my Safespace series and I’ve hit a snag: I want Homo sapiens to have been abducted from Earth about 10,000 years ago so that when humans expand to the wider galaxy, they find “...
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What are the parenting options available to species that reproduce by fragmentation?
How would a species that forms new life only when the parent fragments, do parenting?
Like sea stars and molds, my species forms a new child when the parent is broken. However, this is the only means ...
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Is a species that mates by "tribadism" possible?
In real life, there are planarians that are hermaphroditic, which means that they produce both eggs and sperm, however, they have penises and scrotum without clitorises and vaginas. They sexually ...
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How would "barbie doll" anatomy work?
A fairly common trope in fantasy is "barbie doll anatomy". Effectively, a species completely lacks any visible orifices besides their mouth and nose. This brings up two major questions. ...
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How can I make this mode of reproduction make sense?
I'm workshopping a sapient fantasy species, that, in lore, was designed by external forces to be a biological weapon. This species accomplishes this with a form of sexual parasitism that enables them ...
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Would an asexually reproducing Humanoid species have any form of romance or sexual pleasure?
So I have a setting where the main sapient species is a very closely Humanoid race. In this setting, Humans, along with many other species across a number of dimensions, are all descended from an ...
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How might a race of humanoids with haplodiploid sex determination reproduce artificially? [closed]
I'd like to have unique fantasy type 'races' in a world which appears as a typical fantasy world, but is in fact set far in the future after an apocalyptic event.
I'd like one of these races to be '...
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Is it biologically feasible for a humanoid species to have both types of germ cells?
I thought up a race of humanoids called Daemons for a Homestuck-inspired video game/webcomic. I won’t go into a ton of detail about them, though if I wanted to, I could fill up nine whole questions. ...
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Can a species with the ZW sex determination system be viviparous?
I imagined a hypothetical species of squamate from the Anguimorpha clade. They are my dragons. They are a rare example of viviparous nonmammalian tetrapod. However, like all anguimorphan squamates, ...
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Formula for calculating aging rate of a decaying half-elf dynasty
A powerful human king had a child with an elf princess. His life expectancy is about 70 years (human average), hers is 2000 years. The half-elf prince is expected to live for about 1000 years, more or ...
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Could synthetic pheromones affect female fertility?
In a previous post, I asked what chemical agent can cause both nervous and reproductive effects.
The chemical agent in question should have the potential to be fatal and preferably exert its effects ...
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What chemical agent can cause both nervous and reproductive effects?
In a realistic dystopia, warring religious sects turn on each other using chemical warfare, resulting in mass destruction. Because of the nature of their beliefs, these sects avoid technology; thus, a ...
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How could a species have two sex-determination systems?
I imagined a tetraploid species of teleost. This species has both XY and ZW sex-determination systems. I call this strange thing the VYW sex-determination system.
Genetic females have three V ...
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How does Jimmy Hopkins the giant unicellular organism reproduce?
(Previous Question)
Recap:
Jimmy Hopkins (yes, that's his name) is a extremely weird organism.
For one thing he is extremely large, but on the other hand, he is
extremely weird, because of one thing- ...
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Is it possible to breed extremely peaceful humans?
There is a dictatrix (female dictator) who is a well-intentioned extremist. She wants to make humans as peaceful as capybaras by only permitting humans who are empaths/sympaths to reproduce, humans ...
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If human babies are born underdeveloped, how long would pregnancy need to be in order to be considered fully developed? [closed]
In my world there is a certain sapient species with height around 3 meters, whose bones are more durable than humans, meaning they can afford wider pelvis than most human women
I personally believe ...
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Is there a paternity test method given medieval level technology with low false positive rate?
Determining genetic fatherhood is very important in my worldbuilding experiment for lots of reasons, one being succession, but regardless it's the genetic component that's important But it's possible ...
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What characteristics would my Enslaver Aliens find attractive in each other? [closed]
Each photo I have here is that of an Enslaver Alien. Thank you midjourney for helping me create these creatures. They are an alien species that can grow to the size of a fifteen story building and are ...
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How can sperm become embryos without ovum or eggs? [closed]
How could I make sperm become an embryo or turn sperm into ova so the embryo is grown inside the sperm and then grows in size until hatching in water like external fertilization and get paternal ...
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What are the evolutionary advantages of males wanting females to mate with other males? [closed]
What would cause males to evolve to want the females to mate with other males?
Males use mate sharing as a bonding method for males and to combine their bloodlines with unrelated males to gain ...
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How would men survive without women?
What could make a male-only human reproduction system exist, which makes women obsolete, expendable, and also gives men full control over their paternity?
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How to make sperm competition impossible for males?
How to make an reproductive system where the males have 100% guarantee of their paternity and make cuckoldry and sperm competition impossible similar to seahorses,where the males get pregnant and can ...
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How would sexual reproduction work in a species with three different sexes?
For the purposes of this question:
The species is multi cellular and from an animalia like kingdom.
Sex is only physically possible when 3 individuals of all 3 sexes are present together. With only 2 ...
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Is it possible to have a planet where most of the sexually reproducing organisms are monoecious?
Creatures on Earth has 2 modes of reproduction, sexual and asexual. Most species employ only one of the two strategies, but a handful use both. Those that engage in sexual reproduction are either ...
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Would humans crossbreeding with animal people cause more birth defects? [closed]
I am working on a world inspired by witcher where humans and animal like race live together.
would for example, human crossbreeding with water dwelling humanoid cause something like mermaid syndrome?
...
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Do androids left on their own have any hope of replicating?
The scenario goes something like this: In the not so far future a fully automated exploration vessel crashes on an uninhabited planet not unlike earth. Unlike earth however, this particular planet is ...
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Impact on genetic diversity with 6 person mating groups
Context
I know enough about genetics to know I need to ask others. I'm writing an alien humanoid species that revers the number 6 as part of their culture and religion. Their marriage equivalent forms ...
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What kind of reproduction methods would allow for an only male animal species to exist?
I was reading that there are certain species of starfish which fission made them in some locations to have a scarcity of female starfish and in other locations there are species which only male ...
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Why and how would a species reproduce exclusively by converting other sapient beings into more of their own kind?
In a story I'm just beginning to write, the aliens who have invaded Earth have a ghastly secret that is about to become known: They reproduce exclusively by transforming other sapient beings into more ...
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Can fertility be tied to an individual's strength?
So I've got this species of nocturnal humanoids that reproduces asexually, or rather, they use a form of parthanogenesis for their reproduction and have only one sex.
I've got them figured out for the ...
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What is the stumbling block for a world of "Alphas"? [closed]
In 149597871's utopia, there will be no need for that as only a small minority of "alpha" males would be allowed to impregnate girls while the rest of the (beta) men will only support them ...
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How could my hybrids from species of the same genus with radically different appearance have more fertility issues but still be mostly fertile?
I want to know if my interspecific interbreeding is realistic or a total fiction.
Most animal hybrids are sterile (mostly the heterogametic sex according to Haldane's rule). Some famous examples ...