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Comment by yieldcrv | Hacker News Reader

mutations that occur after reproduction are never weeded out since the genes are passed on already, so natural selection on its own can result in this, just like cancer or lower safeguards against cancer such as short telomeres in humans

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This isn’t quite true, is it? A mutation that killed 5 years after childbirth would result in higher mortality rates for the child.

Octopus have extremely high mortality rates and extremely large litters, so there’s that

They don’t raise their offspring

Ah yeah, I was thinking humans

Though FWIW, they do protect their eggs quite well.

Isn't this tied to the senesce? Where their digestive tract has closed and they starve to death at the nest

Indeed, AFAIK. I've never seen an explanation for this. Most things that reproduce successfully want to do it again - or at least their DNA does. Perhaps octopuses are simply disappointed by the experience.

Octopus senescence isn’t a choice. It’s a fully programmed part of their life cycle. There’s a bunch of hormones released by the optic gland that put them in this stage where they stop eating, stop healing, and sometimes even mutilate themselves.

For the mothers, the entire time is spent cleaning and blowing water over the eggs.

It’s generally accepted this behavior is the necessary pair to their high aggression and cannibalism. It’s likely if they didn’t go through this they’d end up eating their babies. By dying, they make way for a new generation. And this is their reproductive strategy. Live a short very active life. If you survive, mate, then die and leave the hunting grounds to the next generation.

That explains how the mutation was promoted

But not whether other adaptations could be possible. Fix the digestive tract issue and keep the female well fed and defending the nest in a different way

There's no single mutation. Nor is their sensecense merely a digestive tract issue. This is a core feature of their lifecycle. If you mutate the genes that make the hormones that trigger it, or the receptors for those hormones, you won't just prevent their sensecense, because those genes have other functions important to other parts of their life cycle.

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