> octopoda are semelparous--they procreate once, and then usually die not longer after. I wonder if this is their Great Filter, preventing the emergence of more cooperative, social behaviors among themselves that could potentially put them on the path humans found themselves on.

The fact that they are solitary is a much, much bigger obstacle than the fact that they die quickly.

In my eyes their solitude and their short and fragile lives are what caused them to evolve to such a fascinating creature. Just like the human's fragility: no inherent armour, no inherent weapon, no inherent speed. If you can survive under those conditions, you'll certainly be interesting.

Other Minds by Peter Godfrey-Smith has some interesting thoughts about this.

The gist is that because they have such (relative) short lives, their lessened need to be defensive allows them to be more curious.

>Certainly I think ... covids and some other groups, show that intelligence is rather easy to come by

Oh shit I hope not!

> squid, along with covids

Spellcheck has eaten the R in corvids. Another reason to hate 2020.

The ocean is their great filter. Ocean animals are very limited in their tool use - there's not much in the way of rocks or sticks to be had. Some shells and corals. And fire is off the table. I would expect it to be true that any technological civilization has to live on land at least part of the time.

No fire means no energy or metals which means no technology more advanced than the Stone age.

It’s pretty hard to rule the land from the water. Even with all of our technological might, do you think we could wage war on an ocean-bound technologically advanced species? They have the same disadvantage. In all likelihood we would coexist.

there is some pretty good sci-fi about intelligent octopuses[1], one of the coolest ideas is how a society might evolve in a way that reflects the animal's nervous system, i.e. more of a distributed thing than our centralized one.

(Though one should put in the time to also read the novel of which this is a sequel, which is about intelligent spiders, and is also pretty nice.)

[1] https://en.wikipedia.org/wiki/Adrian_Tchaikovsky#Children_of...

They would need to solve the problem that was easy on land: how do you release an energy from one resource to thermally pricess other resource (food at first but then metals).

What could possibly go wrong?

In some species at least, it’s not really suicide, more of an all-in reproductive strategy. In these species, a female will stop eating so that she can spend 100% of her life tending to the egg mass, protecting it from predators as well as using her arms to circulate water around the eggs for proper oxygenation (the mass is stationary, usually adhered to rock or an otherwise sheltered crevice).

Unlike fish eggs, octopus eggs generally take several weeks to hatch once fertilized. Going this long without food basically starves the brood mother to death (or makes it exceedingly unlikely that she will be able to recuperate on her own).

I realize you still could describe this as suicide with extra steps, per your comment.

There is a gland behind their eyes that helps kick off senescence as well. I vaguely remember that removing this gland increases life span.