[nabla9]

Answer to both of your questions is that there was no evolutionary path. Evolution is blind and path dependent. It only responds to differential pressures affecting just now. Evolution is like greedy search https://en.wikipedia.org/wiki/Greedy_algorithm

They didn't develop longevity because intelligence + longlivety does not provide immediate advantage.

They didn't develop collective strategies because they the path path to collective strategies providing gains is too long or too unlikely to happen.

[iguy]

Yes. But I'd reverse these questions: why so much intelligence, with seemingly few opportunities to use it?

[nabla9]

Most likely because they have complex tentacles that need fine motor control. Their brains developed to control their body. Their eyes seem to be good as well.

Even in human brain huge area of brain dedicated into hands. Human fine motor skill (or dexterity) is superior compared to other apes. We can do small detailed moves. Other apes and monkeys are clumsy.

After the complexity of brain developed to control their dexterity, octopus gets benefit from spatiotemporal intelligence to exploit tentacles in hunting and moving. It's not surprising that intelligence plan and solve problems as well.

[iguy]

I guess that's it. Some other asocial animals are pretty smart, because they need it for hunting, or something. (Although even the most anti-social mammals still interact with their mom!)

[cylon13]

The marginal intelligence point makes survival to reproduce more likely, so octopi that are marginally smarter tend to be slightly more likely to reproduce.

However, they seem to die very soon after mating for some reason related to their evolutionary history. There's no way for a marginally longer-lived octopus to be more successful at reproduction, because reproduction is a one-shot event for them. If anything there's pressure to reproduce (and die) at a younger age, since these octopi would be more successful.

Such are the tragedies of evolution, the blind idiot god.

[nabla9]

Octopus genome and weird epigenetics another interesting aspect in them and probably related to their intelligence. Octopus can do RNA editing.

https://www.nature.com/news/octopus-genome-holds-clues-to-un...

Trade-off between Transcriptome Plasticity and Genome Evolution in Cephalopods https://www.cell.com/cell/fulltext/S0092-8674(17)30344-6

• Unlike other taxa, cephalopods diversify their proteomes extensively by RNA editing

• Extensive recoding is specific to the behaviorally complex coleiods

• Unlike mammals, cephalopod recoding is evolutionarily conserved and often adaptive

•Transcriptome diversification comes at the expense of slowed-down genome evolution

[hermitcrab]

They live in complex environments. Often on the boundary between water and land. And some octopuses, do seem to make good use their intelligence - for example the mimic octopus.

[iguy]

I guess an important thing is that they hunt in this environment (in which clams also do just fine). And, like us, they don't have much bodily defence against being eaten by others.

[hhjinks]

> intelligence + longlivety does not provide immediate advantage

You gotta wonder what sort of environmental pressures make intelligent animals less fit for survival by creating communities. Few predators? Very simple environments that don't require passing on information to future generations? High competition for resources?

[nabla9]

Energy and nutritional requirements, longer time before reaching adulthood. For humans one of the limiting factor is the female pelvis. Births become more difficult.

[cwkoss]

I wonder if anyone is breeding cephalopods for longevity and intelligence