I'm trying to insert a bit of weirdness into the world I'm building, and one of the ideas I'm toying with is to have one of my 3 alien races practice oral castration as a core part of reproduction. Essentially, at the height of reproductive intercourse, the female of the species would eat the reproductive organs of the male (entirely, so testes, penis and any covering skin or other organs) directly from the male's body in small bites.

The male would survive this and regrow the organs over a period of weeks. he can do this a limited number of times (though it's a high limit, somewhere in the low hundreds), and after the last iteration he would effectively be sterile. Only the male can regrow their reproductive organs, and only those organs in full.

I currently have 3 core nonhuman races planned in a space comedy adventure setting (with some inspiration from the works of Douglas Adams and Mass Effect), one of which I'd like to give this trait:

  1. An insectoid species based on Earth's dung beetle that's incredibly durable, but slow;
  2. An avian swarm species based on hummingbirds that is incredibly fast, but physically weak;
  3. an amphibious species based on squids and snails that is incredibly strong, but physically fragile.

All species above are capable of FTL travel, so they're not primitives or pre-FTL species.

I'm trying to come up with an adequate reason why this trait evolved in this way in one of these races (Just one of them). I'd really like it if this trait was an absurd cultural evolution, and the biological benefit is only marginal.

I know I could make this trivial through methods like "the genitals contain vital hormones needed for conception" or "the semen needs to be ingested for conception, and having the genitals included means they stand a greater chance at survival", so I'm hoping for something that isn't a base reproductive drive and can also serve as part of the comedy.

Information on the races:

  1. The insectoid species evolved on a world with incredibly high oxygen values in the atmosphere, allowing them to grow to the size of an Earth giant tortoise. Because of their high oxygen environment, wildfires were common, so they evolved to grow an incredibly heat resistent exoskeleton that can withstand toppling trees, as well as an organ that allows them to metabolize certain oxygen-rich molecules into oxygen so they can last prolonged periods without air. However, their massive armor and bulky breathing organ makes them incredibly slow.
    Their culture is incredibly protective and sheltered. they are slow to make friends outside their own community and stick together in the same community. Pactite (the magical element in this world that's common among the 3 races and humans and which is explained in detail in Can my special material with these properties resolve the right bottlenecks in human technological progress?) gave them the ability to innately read minds and motivations. They can't read individual thoughts, but they are able to understand the instinctive emotions of others, as well as understand their motivation. This allowed the individuals to realize that nearly the entire race wanted to make friends outside their smaller community, leading to greater social contact and a kickstart in technological development. The later antigravity properties of pactite allowed the race to shore up their slowness using private antigravity platforms, allowing them to keep up with humans, the next slowest race.

  2. The avian species evolved with 4 wings and 4 claws and is about the size of a hummingbird. They evolved in a world revolving around a star with frequent dangerous radiation eruptions, forcing them to be able to quickly seek shelter among the specialized fauna and flora of the world. The species can use tools in the front claws, but can't fly well while wielding them, forcing them to drop every possession if a gamma ray eruption occurs.
    The species is very focused on group society. polygamy is the norm, often involving dozens of partners of either gender. They are very quick at making new friends and love to socialize.
    Pactite gave this species a global hivemind, allowing them to greatly optimize their society and go from a loose gathering of polygamous family units to a tightly integrated society where everything and everyone is free, as long as it improves the community.

  3. The amphibious species evolved on a high pressure, high gravity world in a young system with relatively many tiny meteorites that only just made it to the ocean floor. The species evolved to be able to lift nearly every meteorite under water in search of foot and mates. The species exists of a thin organ sack with long suckerless tentacles, allowing them to squeeze themselves into any opening or wedge their tentacles under any object. however, being 4 times larger than the next biggest species, they never evolved any defensive measures against other creatures, leaving them physically fragile against sharp objects.
    The squid society is complicated, effectively consisting of a volatile hierarchy of strong and stronger. The strongest creatures rule the planet in a council. Any member of the race can challenge any other member of the race to a duel for their rank in society.
    Pactite made a fundamental change in this society: it allowed them to mind control each other, changing the society from a game of violence to a game of wills. Mind controlled targets are mentally broken, making them entirely subservient to the rest of the species. It also makes the victim nearly infertile. However, any offspring they do create end up dramatically stronger. This creates a system where the descendants of mind controlled slaves may one day end up taking over.

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    $\begingroup$ Because reality has a well-known liberal-progressive bias? $\endgroup$
    – John O
    May 12, 2020 at 14:58
  • $\begingroup$ One of the myths about shaving is that the hair regrows "harder and thicker". It is demonstrated to be false, but basically every human being believes it is true. Just apply this myth to the removal of the male reproductive apparatus... $\endgroup$
    – McTroopers
    May 12, 2020 at 15:17
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    $\begingroup$ Since you're asking what appears to be a cultural question (surely this reproductive mechanism physiologically evolved early on!) can you provide some background on the cultures involved? Right now, all the answers are not only wildly speculative but also opinion based. I think you've got a really good worldbuilding query here, but you'd really need to provide some "constraints", some criteria that successful answers should follow. Am only voting to close because there's not information to provide any kind of answer that's not just a fishing expedition. $\endgroup$
    – elemtilas
    May 12, 2020 at 16:27
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    $\begingroup$ @elemtilas I hadn't actually thought about the rest of the racial cultures yet, to be honest, so you've somewhat put me on the spot. I'll write a couple sentences on each race that I can make fit based on what I want each race to embody in the world I wish to create. $\endgroup$
    – Nzall
    May 12, 2020 at 17:56
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    $\begingroup$ this already exists in nature it is called Apophallation. sea slugs not only do this they can regrow the penis very quickly and has several undeveloped penises ready to go. Part of the reason they do this is to prevent the female from mating with other males. $\endgroup$
    – John
    May 12, 2020 at 18:22

2 Answers 2


During the period between the castration and the regrowth the male is, obviously, not distracted by the urge to mate and can devote his time and energies to taking care of the prole.

This ensures a higher chance of survival to the prole itself and makes the female also more willing to mate again.


The ability to regrow male parts could come from a period in which an ancestral species practiced "sword fighting", if you get my meaning. Winner gets to mate because, well, he's the only one still able to mate.

Millions of years later, since that organ can regenerate there is not much harm in losing it once or twice in a lifetime. It may have been that the species once met humans, and during human-alien interactions inevitably they will end up hearing the expression "eat my [redacted - be nice]". The aliens responded literally, liked it, and then a tradition started.

Now the alien society is obsessed with this kinda meat, and that's the first thing they offer to heads of state, diplomats and such high officials when meeting them. Refusing to eat their [redacted]s is considered the ultimate offense and is known to have started interspecies wars.

For a bit of reference humor, many different dishes can be made with [redacted], all with names coming from human culture:

  • Nightwing/Robin/Grayson
  • Dastardly (Yeah I'm old)
  • Tracy (told you I'm old)
  • Cheney

Etc., etc.


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