[picometer]

The replies to this comment are zoning in on the epistemological dilemma it poses. Soliciting theories for one of the most difficult scientific puzzles, on HN of all places: do you expect someone to serve you up a neatly-wrapped viable and plausible mechanistic theory?

And yet, I think it’s a serious comment, not a troll, because this is the right epistemic stance. We don’t know how life emerged yet and this is rightly uncomfortable.

As for the object-level topic: I’d direct my attention to any research that investigates the relationship between the cell wall and the inner organelles. I suspect that the viability of the cell factories was dependent on its co-evolution with the cell wall, which, by creating a semi-closed (permeable) system, would change the entropic conditions inside the cell.

[cmrdporcupine]

I agree I think the cell is key as its the foundation of the energy dynamics of the cell.

And re: the epistemological questions, etc: I think there's a temptation for people to look for a transcendent, teleological prescription for the 'why' of life; which can range from either 'God' to some abstract 'progress' concept where nature proceeds to 'higher stages' etc (panspermia, gaia, whatever). It's deeply part of at least western culture since at least Aristotle and Plato to use these kinds of tools.

But I believe the 'answer' here is just a big messy 'immanent' one rather than any transcendent order. Life happened as it happened because it happened... and it will unhappen someday, too.

And of course we would not be here to ask questions about it if it hadn't, so is it really a puzzle that needs a formula to answer it?

Humans look for "reasons" for things because that's a useful conceptual tool for understanding why other people in our kin groups do things, or why a herd of gazelle we're hunting is in a particular place, or why a plant we harvest from didn't grow well this year.

But there's no reason to assume that this conceptual tool makes any sense for understanding "life" or "existence." It's a crude instrument. At that level, there is no "why", there is only "is".

(And I'd posit further we should not make assumptions like "oh it happened here [us] so it must have happened elsewhere because <xxxx principle / transcendent order / natural progression> ... so ... Star Trek!"; the universe is massive, yes, but that doesn't mean the precise events duplicate multiple times and it does seem like complex multicellular life was a kind of ... fluke ...)

[User23]

We don’t even have a good grasp on what life is! Try to get an explanation of why a living thing is alive, but when it dies despite having the same observable material condition its corpse is not alive. I’ve yet to hear anything beyond the most obvious begging of the question; it’s always some variation on living things are alive because they have life processes and nonliving things aren’t because they don’t. And what’s a life process? Well it’s a process that occurs in living things of course.

[deadbeeves]

I'll take a stab at it: a multicellular organism dies when the processes that are able to sustain the operation of the cell community cease, thus causing the individual cells to die individually or to live as single-celled organisms in the wild for a short while. The main processes that are essential to the life of an organism as a whole are the supply of nutrients and oxygen, the elimination of waste, and the coordination of various support activities between different groups of cells in the body. They're essential because most of the cells have delegated the capacity to perform these functions to the organism, allowing an increase in efficiency at the cost of tying their survival to the survival of the organism.

A cell dies when it's damaged mechanically or chemically, or when it's unable to sustain its metabolism thus causing chemical damage, or when its programming instructs it to destroy itself for whatever reason.