Quick refresher ...

I'm considering the two basic strategies of child-rearing. R-selection, meaning you have lots of offspring and don't care for them much; and K-selection, meaning you have a few offspring and take very good care of them. Humans are the poster-species for K-selection, and most fish are a great example of R-selection -- they spew out zillions of eggs and then abandon them (either at laying time or hatching time, depending).


Let's imagine we have some kind of clever land-octopus alien which casts its eggs to the wind. They want to evolve intelligence and build a civilization, but will have severe problems building any kind of continuity. Is there any hope for them?

Edit: Distinction from possible-duplicate question is this... I'm questioning whether they would even be able to group together. Aside from some (creepy, scary) insect tribes, most R-selecting land creatures are asocial and see the offspring as competition or -- heck! -- snacks. A possible pattern that might be interesting is fish schooling; the fish don't care for their young, but they clump together as they grow anyway. That might be a template for tolerance of one another's presence.

Another thought is that you might have these R-selecting parents herd their own offspring. Offspring are nimble enough to catch small prey that parents cannot, so parents keep them around, eating the biggest near-adults and gaining benefit from prey sources that they can't catch themselves.

  • 4
    $\begingroup$ Possible duplicate of How would society be different in a sentient species that does not care for its young? $\endgroup$
    – kaine
    Aug 25, 2017 at 17:13
  • $\begingroup$ Neimoidians are r-selection (Star Wars) $\endgroup$
    – Jeutnarg
    Aug 25, 2017 at 18:56
  • $\begingroup$ for duplicate voters, the question is different from that "Would they even form a society as we know it with no incentive to group together to protect their young?". The pointed as a duplicate has an incorrect question by nature of things, focusing on magical get together to protect their young. Those species get very well together, but for other goals. This, OP's question asks about creating complex civilization. The answer is yes, potentially they can. $\endgroup$
    – MolbOrg
    Aug 25, 2017 at 19:26
  • 1
    $\begingroup$ @MolbOrg Was this intentional irony with the duplicate comments about duplicate voters? $\endgroup$ Aug 26, 2017 at 1:54
  • $\begingroup$ @fyrepenguin no it is a glitch, tnx for informing $\endgroup$
    – MolbOrg
    Aug 26, 2017 at 11:50

9 Answers 9


Then, on a given day, an adult specimen has a brillant idea:

So much eggs and infants wasted and so many hard work to do here at my farm...
Why not farm those eggs and infants in order to make most of them reach adulthood? This will maximize my profit!

And subtly your R-selection begins to switch to K-selection. Then, the K-selection people would use technology to outnumber the R-selection ones driving them to extinction.

Except if something makes that be a really bad, impracticable, inefficient or impossible idea. There must be some important selective pressure that prevents a switch to K-selection and keeps R-selection favourable.

Some species uses R-selection here on Earth for many possible reasons like:

1) The adult can't really take care of its children without other dramatic adaptations to its body.

2) The adult can't even properly take care of itself or its sexual partner. No way to take care of offspring. It would be just easier to produce zillions of offspring and even if 99.9% of them don't reach adulthood, there would be enough for the next generation.

3) 99.9% of the offspring is sterile. Specimens able to reproduce are an elite. This happens with ants and bees, for example.

4) 99.9% of the offspring has disabilities and malformations that render them unable to survive childhood.

5) The adults dies shortly after the production of offspring and won't be able to ever see them. This happens with some insects that live for many years as eggs or infants and just a few days as adults.

6) Eggs and offspring are produced in the environment without the parents even being unable to acknowledge that they did that. This happens specially to plants and fungus, but may also happen with some fishes.

7) The eggs must be implanted in a place where the adults can't live. The infants and adults live on separate environments and would quickly die if one invades the environment of the other. This for example, happens to mosquitos, where larvas live in water and adults live in land and air.

8) In order to become an adult, the child must be able to encounter enough quantity of a rare resource or be able to develop a hard and costly skill.

9) The males and females are radically different and one of the sexes for some reason greatly outnumber the other. Only members of the elite sex are intelligent.

10) The males and females are radically different and one of the sexes for some reason greatly outnumber the other. Only members of the elite sex are not intelligent.

11) The males and females are radically different and one of the sexes for some reason greatly outnumber the other. Both sexes are intelligent.

12) Infants compete harshly and promptly kills each other until the last man standing.

13) Probably other reasons that I don't know or just forgot about.

Numbers 1, 2 and 5 are probably unable to ever evolve some appreciable form of intelligence at all.

In the case of 3, there would not even be the mentioned brillant idea because farming offspring is exactly what they are doing as a species, so they already somewhat care about their childs and this is not what you are looking for.

On number 4, they might farm offspring and select and care only for those that are able to reach adulthood, disposing the rest.

On number 7 and 8, once the species is able to gain superior intelligence, it will start farming their eggs and possibly either revert to K-selection or to some artificial form of number 4 - "Select the best one childs, kill the others. We know, this is sad and cruel, but we have no choice, we can't raise everybody."

In the case of 9, 10 and 11, once the species becomes intelligent, the members of the elite sex receive great care and attention of the offspring while the members of the opposite sex are artificially selected with all the rest being discarded (like 4). Don't expect that they will even think about closed marriage, genre-equality of sexual freedom, this would be really absurd ideas for them.

In the case of 12, through the use of the brillant idea, intelligent parents would separate all or most of the offspring and raise them separated. This will make them tend to switch to K-selection after some millenia of widespread offspring artificial selection (like 4).

Number 6 is the best:

A male is selling some items in the market. A female customer just comes in. After some seconds of a friendly talk, she gives him the cash and gets the item she just bought. He thanks her and she answers with a smile and leaves. They have no idea that they just had sex and their fecunded eggs are now being carried away by the wind, but won't be surprised if someone tells them.

  • 3
    $\begingroup$ Victor, this is an amazing response. I think you're closing in on what we need to do. So let's turn this around and have the kids have the brilliant idea. They know that Dad is essentially ranching them, because they can eat bunnies that Dad is too ungainly to catch. So some of the kids start bringing bunnies to Dad as a "please kill me last" gift. Which, over evolutionary timeframes, makes Dad willing to tolerate the presence of at least some children. $\endgroup$
    – akaioi
    Aug 28, 2017 at 0:34
  • $\begingroup$ @user54373 Yes. This also tends to make the childs compete each other for resources that please their parents, which could eventually lead to #12, although that small groups might collaborate or be divided in gangs warring for the right to please Dad. $\endgroup$ Aug 28, 2017 at 1:02
  • $\begingroup$ @user54373 Further, cannibalism is biologically unfavourable and most species that shows that have a tendency to get extinct sooner than later. For many species (and even humans), members of a tribe only canibalize members of other enemy tribes, not their own. Rarely something canibalize their own kids. Further, any superior intelligent society would probably feature ethic/philosofy values that would render canibalism being saw as bad and would try to erradicate it. So, if you want parents canibalizing kids, you will need a very strong reason for not allowing that be eventually ruled out. $\endgroup$ Aug 28, 2017 at 1:05
  • 1
    $\begingroup$ I'm imagining that the main deal is not the cannibalism (though they're willing to cannibalize each other, and this ranching behavior happens in unfriendly climes where other food is scarce)... I'm trying to figure out at least a "Just-So Stories" version of how these r-selectors learned to tolerate their own young enough to keep them around and build a civilization. If the young simply scattered, there'd be no way to accumulate knowledge over generations. In the modern world, "Only stupid hicks ranch their own children" $\endgroup$
    – akaioi
    Aug 28, 2017 at 1:18
  • $\begingroup$ @user54373 I can imagine that the only reason to not raise your own children would be if trading child is more economically or biologically viable than keeping them all. This is possible if specimens only acquire intelligence in adulthood, but reproduce in teen ages, being no smarter than a dog when underage. Keeping your own children close produces really bad grandsons/granddaughters due to frequent brother-sister sex, so the solution is to export your own children and import children from as many different people as possible. [continue] $\endgroup$ Aug 28, 2017 at 2:34

An example in fantasy: the Grik

In Taylor Anderson's series Destroyermen, the Grik are an r-selected species of reptiles which have an impressive (and mighty powerful) civilization; the trick is that in their lifecycle they have two phases: an eusocial non-sentient phase when young, sometimes followed by a fully sentient and sapient phase when older. The eusocial young make brave and obendient soldiers or tireless if unskilled workers, while the actual civilization is built and maintained by those relatively few fully sapient adults.

(For completeness, Destroyermen is an entertaining parallel-world adventure series of novels, following the crew of an American Wickes-class destroyer which is displaced to a parallel timeline during the Second Battle of the Java Sea (March 1942); in that parallel timeline Earth is inhabited by two native sentient species, the above-mentioned warlike reptilian Grik and the relatively peaceful Lemurians, plus the humans brought there by several timeline-displacement events. Besides the expected military fantasy, it includes at least two cute cross-species romances.)

  • 6
    $\begingroup$ "the trick is that in their lifecycle they have two phases: an eusocial non-sentient phase when young, sometimes followed by a fully sentient and sapient phase when older" Sounds a bit like the Pak from Ringworld/etc. $\endgroup$
    – JAB
    Aug 25, 2017 at 18:28

You seem to be focusing on continuity as in having parents to transmit things to their offspring. I don’t think this is the best angle for this.

Ants are a good example of r-selection, and seem to be doing pretty well without teaching anything. But they are unlikely to develop a civilization because of their limits.

r-selection is based on creating a large amount of offspring, which requires the offspring to cost as few resources as possible.

Humans reproduce usually one offspring at a time because human babies are costly to make. That’s why we care so much about each of them. Human brains are in fact so big that human babies are born before they are able to sustain themselves and finish their development outside the womb, or else their head would end up being too big to fit.

Unless you find a way to have your species develop a civilization — which implies culture, technology, etc. — without a big brain — decentralized brains, for example — you will have a big problem.

  • $\begingroup$ Yes, I think this will be difficult, because I do want my critters to develop a technological civilization. But if they lack the instinct to care for their young, it's hard to get them to care enough to build something lasting. Your note about ants makes me think you might have a "breeding pits" kind of situation where the adult aliens start caring about whichever "alienlings" survive to crawl out of the pits. Hmm... $\endgroup$
    – akaioi
    Aug 25, 2017 at 15:58
  • $\begingroup$ The "Human baby brains are too big" bit is an interesting point, because it's dependent on two points: 1) Live bearing young - Egg layers don't require as much physical accommodation for larger brains. 2) Brain to Body-mass ratio - there's a largely linear relationship at play here, though humans are a bit of an outlier. It's not clear 100% clear whether that ratio influences our civilization building or not. The Tree Shrew for example, has a better brain-to-body-mass ratio than humans, but they don't have any skyscrapers yet. $\endgroup$
    – Adam Ness
    Aug 25, 2017 at 18:36
  • 1
    $\begingroup$ @AdamNess Still, that's the increase in brain mass made possible by richer food sources that made our kind of apes smarter. If I had to, I would put my money on the increase of mass rather than mass itself : I bet it correspond to the development of new brain areas in addition to the ones already necessary, allowing new functions, like understanding abstractions. I get your point regarding eggs, but eggs must be laid with all the food required for the embryo's growth packed in it, which is why it's mostly protein : it takes as much space as the fully grown offspring. $\endgroup$
    – Sarkouille
    Aug 25, 2017 at 19:29
  • $\begingroup$ @AdamNess Therefore, at the end of the day, because it grows from the initial nutritive input, and because it's limited by the egg's volume anyway, offspring that grow in eggs aren't bigger than the egg itself, which doesn't solve the volume issue. $\endgroup$
    – Sarkouille
    Aug 25, 2017 at 19:31

Negligible senescence (or natural biological immortality) might do the trick. Our huge K-selection bias has led us to civilization and technological development, as you intuit, at least partly because we desire survival/persistence and good lives for our heirs. But if there's no strict requirement that you'll ever personally die, personal survival and prosperity might provide all the motivation one needs to build a civilization. Of course, immortal in this context doesn't mean unable to die, it just means means no degenerative aging and inevitable death from old age.

It may seem at first blush that a biologically immortal r-selectionist would have little reason to organize socially. However, readers of Thomas Hobbes will recognize that one of the strongest motivations to form civilizations is to keep people from bonking you on the head in your sleep and taking your resources. So, so long as the species experiences necessary periods of dormancy which remain occasionally necessary throughout an individual's life, there's more than enough reason to organize socially. (On the other hand, if you're done with dormancy after metamorphosing into the adult form, that provides no civilizing motivation for an r-selectionist at all.) For a biologically-immortal r-selectionist, friendship is the single-greatest survival-oriented innovation I can imagine.

  • 3
    $\begingroup$ I really like this answer. For "natural biological immortality" (at least as described here) the usual term is "negligible senescence". $\endgroup$ Aug 25, 2017 at 21:16
  • $\begingroup$ Thanks, @DeveloperInDevelopment, I've incorporated your terminological suggestion. $\endgroup$ Aug 27, 2017 at 3:53

I would suggest something close to how gargoyles in the animated series by the same name approached child rearing. Gargoyles laid eggs but an entire clan would raise the child and traditionally never acknowledged genetic parental relationships... all children of the newest generation were raised by the collective clan. How punishments and the like was handled was never specified or whether grouping was encourged. The relationship of parents and child was mostly put into a generational gap disagreement where the lead character's daughter turned up. Having been raised from hatching by humans, she wanted parental attention, which was difficult for the father to accept. According to series creator, there was a father/son pair in the core cast, but it was never discussed in series and you could easily miss it. Also, according to the series creator, incestual relationships among siblings or parents was discouraged by a "scent" marker that was only unpleasent to those of the same genetic lines.

Not sure this counts, as it has aspects of both (the R-K hybrid is further mixed by a difficult gestation period (and only one idividual at a time, with a very rare identical twin) and long childhood. That said, this could be easier if the society had community child-rearing and less qualms about childhood death (vacinations would probably be administered in early maturity rather than early childhood, Spartan Parenting is the norm (either be smart or starve)). As a result, the society would likely be seen as barbaric by human standards in some regards, though nepotism and marriage might be unknown to them (no knowledge of who's my kid and no reason to stay with my mate for the sake of the children. This doesn't rule out any favoritism from an elder authority to a younger though... but they would see something in the younger they value and want to foster). They would also probably have a quasi-democratic government as no one is special beyond they lasted longer than their siblings and "weak" bodies would be discriminated against. Parents certainly wouldn't be adverse to letting the brood play with lawn darts and toys certainly would be much more dangerous.


You can still build a civilization with this kind of reproductive system. You just have to gather individuals in group where they can share their knowledge, specially to younger individuals.

So in this scenario, the octopus hatch alone in the wild, with a high infant mortality rate, but the survivor will integrate a group of older octopus, allowing to pursuit civilization.


In Heinlein's Stranger in a Strange Land the civilized Martians produce many offspring who live outside of civilization for some time and most of them die, the survivors are then adopted into civilization.

In Futurama: Kif's species produces a bunch of tadpoles, and gives minimal assistance to get them to water, but then lets them grow on their own (presumably with many dieing) for years until they grow legs and come back on land. Zoidburg's species has a mass spawning the precludes parents caring for their offspring.

The main point is intelligence. If your species has enough of it for adults to have civilization it doesn't really matter how you get new adults so long as there can be a continuity of adults, or they can at least pass ideas and infrastructure to the new generation.


Not unless they were natural readers.

The march of progress only marches if people, as a whole, get smarter over time. In order for an R-Selection species to grow in average intelligence would be if every generation read what the generation before had written.

We take care of our elderly, and have done for a long time. By doing this, they can pass on their knowledge to people who are young enough to use it. They make less mistakes, ergo better survival rates overall.

Without the ability to pass on knowledge, we don't get smarter. You'd need your species to instinctively know how to read and there's no science I know of to suggest something that intricate could be passed on genetically. However, language is definitely "in our DNA" in that we know instinctively how to learn a language and the language we learn is just whatever we're exposed to. So your aliens COULD, theoretically, only communicate in visual cues allowing a writing system to be similar enough to their "vocal" communication that they could instinctively pick it up easier.

It all depends how much "Suspension of Disbelief" you're going for.


Another possibility in which r-selection aliens build a society is if the aliens passed down knowledge through hereditary means, or other automatic means. Passing down knowledge through genetic means doesn't seem possible, but what might be a possibility is if the aliens reproduced in some way that would have them begin life neurally connected to their parents. If their nervous systems were connected at the start of life they could carry forward some knowledge from birth, and then be completely antisocial while still developing to some point. They would again pass on the knowledge when reproducing, so it would not die with them, and technology could develop, though not necessarily a very civilized society.

If the offspring developed inside the parent to a degree they could also have a connection to their parent's nervous system, similar to how the umbilical cord forms a connection to the parents circulatory system. However longer pregnancy generally is linked to k-selection, though I see no reason the adult couldn't abandon the offspring at birth.

One possibility that could have k-selection pregnancies is if the adult died in, shortly before, or shortly after childbirth. This would mean the aliens remained r-selection. In this scenario I assume the children would absorb large portions of the adult as they developed. This would also mean knowledge would likely only be passed down by which ever gender had the pregnancy.

  • $\begingroup$ I'm honestly not sure how this addresses the question of whether an r-selection alien could build a civilization. Can you edit to elaborate on that? As it stands, this answer may be at risk of being deleted as not addressing the question. $\endgroup$
    – user
    Aug 27, 2017 at 8:03
  • $\begingroup$ Welcome to WorldBuilding Braydon! Am I understanding you right that you want children to automatically have the knowledge of their parents and therefore no need for being specifically cared for, leading to the possibility of building a progressing society? It would be nice if you could edit it, as it looks like an answer for me, but the answer made it to the low-quality review queue. If you have a moment please take the tour and visit the help center to learn more about the site. You even get a badge for taking the tour! Have fun! $\endgroup$
    – Secespitus
    Aug 27, 2017 at 8:19

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .