How can I explain why my race has genders but can't reproduce?

Question

I'm inventing a race for a roleplaying campaign, and I thought about making them live really long lives (or even be immune to ageing) and not be fertile, but I still want them to be male and female in appearance even though they don't have a reproductive system.

Is there a way to give a somewhat scientific (it doesn't have to be 100% solid, just believable) reason why they can appear as male and female without having genitals? Can they have gender-determined hormones for some reason?

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Edit:

to clarify, I decided that the members of this race were created one by one by a god, who decided to make them not reproduce but instead live indefinitely long lives (virtually infinite). I was asking for a way to explain the existence of gender traits even without having a reproductive system, just to avoid having to say "yeah it's because that god wanted them that way and that's about it". I mean, is there any reason for there to be gender traits (such as breasts or more developed muscular structure) other than reproduction?

Answer 1

If you take a step back from gender, specifically, and just look at differentiation, there's some value to be gleaned from it. A long-term differentiation like gender can be basically thought of as a long term preparation for something to come.

If the "god" could not create a race where each individual has the same physical traits and have that race prosper, he/she/it might give up, and instead develop two distinct sets of physical traits. For example, it might make sense to have one half of the race more capable in terms of strength, and the other half more capable in terms of finesse. Those two goals would lend themselves to what you and I consider masculine and feminine genders.

One difficult question would be determining the value of it in terms of immortal creatures. In human cases, the ability to prepare for given roles for years before you are even aware enough to choose which role you take, having some of that build into our genetics was really useful. If you have thousands of years to optimize your own strength/flexibility/intelligence to the world around you, there might be less value to differentiation before each individual is aware enough to make a conscious choice about said differentiation.

It also could have been a tool for control. After all, one of the single most effective ways to limit uprisings is to make sure that no one individual is able to do everything. Intentionally give them a weakness that needs to be filled by another, and rebellions get a lot harder to manage.

Answer 2

How about this;

You have one or more gods, who creates the first couple of humanoids.

After a while, another god comes along, and decides that creating sapient creatures looks like a lot of fun, and starts copying the other gods creations.

Except, he didn't really do his research properly. So while he managed sapience, sexes and the whole walking upright thing, he simply missed the self-reproducing part, simply taking the different sexes as the thing to do without question.

Answer 3

A virus, one that infected those with reproductive systems was the main cause of death for a long-lived race, the virus passed down through their DNA and taking lethal effect after a certain amount of time has been reached. Eventually there were those that were born without reproductive systems who were not affected by the virus. Of course these could not pass down any genes whatsoever and were eventually the last ones to survive. This allows those last people to both retain their gender-like traits (due to the way DNA works) whilst not being able to reproduce.

Answer 4

Your race may be a crossbreed between two different races. It is not unusual for such crossbreeds to be sterile.

Their immunity to aging may be explained by this particular crossbreed having enzymes replenishing telomeres after cell division. Which otherwise only would happen to stem cells.

It's quite plausible that such an individual would be quite likely to get cancer and die from it. So it may only be very few of the crossbred individuals with an immune system capable of fighting off the cancer, which survives.

Those few individuals may however be immune to aging and theoretically capable of living forever, though not immortal as they could still die from major trauma.

Normally a sterile crossbreed between two races is not considered to be a race in its own right. However it might be that the population of crossbreeds have over time grown so large, that the two original races have been driven to extinction by the competition for food.

All of that backstory may have happened so long ago, that even the crossbreeds themselves can no longer remember how it happened.

Answer 5

Ancient Greek/Roman grade deities*. They created them for fun but don't like the trouble that making little demi-gods every time they stick it in something creates. Hence they created them sexually capable but infertile.

*If you don't know what this means, read the versions of the myths not targeted at small children. They're a lot more fun.

Answer 6

If you are saying that this race was created by a god then a scientific explanation of gender differences is unnecessary as you already have a supernatural justification for the race to be however you want them to be.

If you want a narrative reason then one option is to say that they were created as different castes to perform different roles in society. Here direct analogues genders as we understand them in humans may be a bit of a stretch in credibility as any reference to gender immediately implies sexual reproduction but some sore of worker/soldier and administrator/academic division would make some sort of sense and has plenty of precedents in sci-fi and fantasy.

Having said that if you are breaking away from a binary gender definition you could emphasise this by having more than two castes. Exactly how this might break down is for you to decide. One well known example of this is the morlocks and eloi in H.G.Wells' 'The Time Machine'.

Something else to bear in mind is that this will inevitably be read as a socio-political statement how much you care about this is up to you.

Of course if they were created by a god, live indefinitely and don't reproduce then that suggest that suggests that each individual alive was directly created by a this god.

An alternative is that they are the offspring of gods, or better still the offspring of gods and some mortal race. This explanation strikes quite a good balance between supernatural creation and fitting in with biological plausibility and established mythological connections.

It's also worth noting that some closely related species can breed and reproduce by their offspring are infertile (eg horses and donkeys) so this would work as a proper scientific explanation and the god aspect could just be their own explanation.

There is some debate as to exactly how biological ageing works but it's certainly not absolutely beyond the bounds of credibility that a biological organism could be functionally immortal eg mole rats are unusually long lived for their size.

Answer 7

Recall the common side-blotched lizard. There are three different phenotypes of male lizards in addition to the female. They evolved into an interesting rock-paper-scissors game within one species with some especially relying on brute strength, loyalty, or slyness. I'm sure you could explain a similar mechanism arising for an asexual species, who would certainly identify to "gender" socially although there is no sexual difference like the male lizards.

Answer 8

The explanation can be completely natural. Their reproduction process requires not just 2 but 3 sexes. Unfortunately, all individuals of the third sex perished because of epidemic/war/natural disaster/whatever. Since that time the race can no longer reproduce.

Answer 9

This 'god' race could be a surrogate race ie: they look after another species and have taken specific roles in their breeding cycle, in this manner you may have a co-dependant or dependant species.

So your 'god' race develops female forms to nurture the children of the 'sub' race. The male forms are to help them physically or maybe in war or some other such reason.

A cool twist would be that the 'sub' race died out millenia ago and because this race just keeps living the individuals still have all their traits.

If the sub-race were living co-dependantly of this other race then maybe you could introduce the idea that they were created as a companion race or whatever to the 'sub' race.

Maybe they used to be able to breed but needed one of the opposite sex of the 'sub' race to do so (different races, same species). If the 'sub' race need this as well (so both races rely on each other to procreate) but did not have the longevity then maybe that was how they died out. The 'god' race just didn't bother procreating enough.

Just some ideas, remember to reference if you use them.

Regards, Damien Holley

Answer 10

Of course.

Former they had a reproduction system and were "normal" males and females, but after evolution or technology-changes, they became infertile and those parts of body degenerated.

Well, if they were created by a god, he did this for fun, or in order to have balanced or more interesting society he created 2 gender.

The funny variant: a god actually wanted to create a one-gender race, but some members were produced with a different gender occasionally or by mistake

Answer 11

You are interested in establishing that each of these beings are brought into existence one-by-one by a monotheistic creator deity. If you are interested in emphasizing the theology of your fictional cosmos, you could make explicit that the God has both masculine and feminine characteristics. God is both 100% male and 100% female; He is the perfect man, and the perfect woman. God deliberately chooses to withhold the feminine characteristics from his men, and similarly withholds masculine characteristics from the women, in order to accentuate both. Or, He intended to make His created beings, the men and the women, mutually dependent upon each other, or wants to prevent them from being capable of rivaling His power. (In the Symposium, one of the Dialogs of Plato, it was explained that humans were originally made as eight-legged creatures, capable of autonomous reproduction, and then were divided into male and female after revolting against the gods.)

Biological reproduction does not happen in your literary universe; but when the people are created, are they physically developed and self-sufficient? Or are the people created as infants? If infants, they would need to be breast-fed, as they are physically incapable of digesting solid food. The women would obviously be incredibly vital for the existence of the species. It makes sense that the God would choose to create the people in this way for the two reasons mentioned above--to make the people loving and caring for one another, and submissive towards God; people that are created as helpless infants could presumably be taught to serve the will of God more easily than if they were created as self-reliant and skeptical adults).

The menfolk, likewise, would be built to perform heavy manual labor and could be the builders, warriors, lumberjacks, etc. Obviously, traditional gender roles in the labor market existed for a reason, and were never called into question until the age of machines and automation. Because the men and the women are dependent upon one another in practical, pragmatics ways, and because they themselves were once children raised by a mother and a father, they would be emotionally compelled to complete the cycle; to seek each other's company and agree to cohabitate with one another, promising each to the other their sole attention for a lifetime. Once a household is formed, the deity would perhaps see fit to induce them to take care of another person from infancy to adulthood. Perhaps a baby would be delivered by a stork? Scratch that; perhaps the deity himself is an avian creature who lovingly flies, delivering gift-baskets from the sky to its favorite humans, similar to the sparrow in the Japanese fable shita-kiri suzume, The Tongue-Cut Sparrow.

Answer 12

Could it be that they weren't always incapable of reproduction or immortal. They discovered the vaccination against death, but it had the side effect of making them infertile!

Most people preferred infinite life to reproduction and took the treatment at a young adult age (before they realised the pleasure of children and families). The ones that didn't were in the minority so it was difficult to find fertile partners to choose from (it was before the age of Internet dating) and to convince their children not to take the treatment, so they eventually went extinct.

Alternatively, messing about with immortality medicines angered the Gods (who themselves want to be the only immortal ones) and so as punishment cursed the population with infertility.

Answer 13

Then you could think why we human have difference appearance in each gender

Remember that many animal in our world doesn't have difference appearance between gender (dog, cat, monkey almost all vertebrate at least). But human is exception

To have difference appearance in each sex is called Sexual Dimorphism

To simplified it. It because each appearance has difference roles and purpose needed for the task, fertile or not, masculine made for doing a muscle work while feminine appearance used for nurture things with soft and caring

Appearance is also a way to communicate. You need to have appearance suit for each kind of communication. Diplomat and negotiation is better with beauty and harmless while masculine needed for warning and intimidation. This is very important if those specie made for communicate with human. Same as Angel in Bible

Even same specie and same sex could have difference appearance. Ant and Bee for example has difference appearance between drone, worker and queen. Some worker ant also has difference size for difference task. Even there are no god if they are hive specie like ant they could be gender but no sex

Answer 14

Your race is so scientifically advanced that they can reproduce in the laboratory of life.

Through the process of evolution, they lost fertility because all beings have created scientifically to better physical and infertile feature

Answer 15

Simple answer: to fit in with the humans. The beings all have different personalities, and choose to assume the gender that best suits them, so they are more approachable to humans, easier to understand, etc.

Either they have some control over their appearance, or their bodies slowly adapt to their personality and self-image as they age.

Answer 16

I don't know if you would like it given your thesis and your goals. However As previously mentioned, you could have them been designed as compliments one for strength one for finesse, or -

You could simply have them adapted to the outside world, and within their culture there is no gender assigned. However, due to their age and the rest of the world having this view of male and female, they do make it easier to interact with the outside world by adopting these traits or forms. So maybe those who identified or idolized the dress and style of women's make up, clothes etc. have become those viewed as women by the outside world when it merely a choice and those who tend to keep shaved or shorter hair, are seen as men.

Or -

That rather than having their own children, these people of this god are born through other races, and once reaching age of maturity have this vision of this distant island they have to travel to, which compels them to when they get there. The true nature of what they are is revealed, and thus it is not so much that they don't have genders but the group of people have ceased to look at it that way due to their so rapid and varying forms. Also see Part B

Also thinking about your immortal race, they could be infertile due to The god's gift which is given to them, that rather than true immortality that it is more a form of reincarnation. When one of them dies they born a new, but this is a form of their soul, that is put into an available body and so the individuals memories and experience survive, but they are constantly changing so gender holds no bounds because for one century I was a man but I have also been women.

And in this way, some may be viewed as we would view children as they are first rediscovering their past lives. And men would be having sex with men and vice versa, some would probably marry, others would probably see it as a burden.

Not sure you will like it but this is just a different take on things

Answer 17

This would be better as a comment. Too bad for rep limits.

You know what makes this whole situation kind of funny?

The number one cause of death would be domestic accidents. I mean, sure you're possibly a god slaying immortal angel, but you can still fall off a ladder. Think about it a bit. Horx the living fire, eternal and unquenchable in death and destruction had a jack give out while changing the oil in his car. Shar, known for battle tactics and some of the most epic showdowns in history, retired at 34,677 years old. She died when her foot slipped getting out of a tub. Tibth, law mower. Gethic, un-watched candle. Yiddith, well it took a good hour to sweep that mess up. Then there was Cecil Palmer, possibly a street cleaner or Kevin.

Biological immortality really kind of sucks. Plus everything that does die of old age would want to research said creatures. I'm not talking a few camera's and some long range watching. I'm talking taking it apart while it's living. If it's really immortal then amplify the horror. You CAN'T die...

Your best bet is to not explain it. Just kind of play with it. That's what J.K. Rowling did with magic. There was some half-back explanations, but it was always "A wizard did it". If you get caught up explaining it now, you can't change it later. Plus it might come off as an info dump which will bore readers. I rely on unreliable narrators to avoid the pitfall of a good explanation.

Answer 18

Is not having genitals important to the story? Since your “deity” is not part of the story, you can assume evolution instead of creation. This species became dominant because of their longevity (and other factors, if needed). Since you mentioned their combativeness in another question, they may have wiped out the competition before starting on each other. Meanwhile, because of their longevity, and the fact that they are more interested in fighting than the other f-word, the gradual loss of fertility* did not prevent their dominance.

*or the appearance of a virus as suggested by CEObrainz