Humans are tool users and through their ingenuity were able to hunt much larger animals than themselves.

Specifically, I would like to have a race of sentient beings based on octopuses. They use tools, and are able to make nets and traps for other sea-life. They can plant crops and can hunt and kill creatures much larger than themselves by team work. They never emerge from the ocean. All their activities take place under water.

What would have to happen for such creatures to evolve or is there something that would prevent their appearance?

  • 1
    $\begingroup$ Seems like a fair question. The wording might be off but "is it possible for sentient octopi to evolve" seems like a solid worldbuilding question As far as I'm aware octopi are one of the smarter species in the sea despite their limited size (excepting a few races of octopi). The biggest limiting factor seems to be age and social structure: they dont live long enough to really acquire knowledge and wisdom and dont have the social structure to pass on knowledge and infrastructure to offspring. A long lived social octopi society could pull it off. $\endgroup$
    – Demigan
    Mar 30, 2019 at 12:00
  • $\begingroup$ @Demigan - Thanks for the feedback. I've edited to make it closer to your suggestion. $\endgroup$ Mar 30, 2019 at 12:15
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    $\begingroup$ The answer is: of course there could be. Most things could be. Look at evolution, 300 million years of serious life, 5 billion more to go and man appeared 40k years ago. There is nothing more to say about that. There is no evidence to quote, no study being funded, no further information to be given. Anything else is just bsing around. So I've got a question: what do you really want to do? Maybe one can help you ask a question that really leads to something useful during the construction of your world $\endgroup$
    – Raditz_35
    Mar 30, 2019 at 12:28
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    $\begingroup$ This will ineviteably end up with "what conditions would make octopi evolve long lifespans and social structure". Just yesterday I saw a cat catch a crow, its 3 fellow crows flew up, circled while making noise and then dove towards the cat which releasee its prey, allowing it to fly away (I also saw a dove get caught and its fellow flew away. It was a weird day). This shows how social support can help survive predation. If scarcity is introduced and teamwork like breaking open tough/large critters or farming is required to survive you have two potential ways for social behaviour to develop. $\endgroup$
    – Demigan
    Mar 30, 2019 at 13:39
  • $\begingroup$ Related: worldbuilding.stackexchange.com/q/66139/28 $\endgroup$ Mar 31, 2019 at 3:23