The Origin of Death (1970) | Hacker News Reader

The Origin of Death (1970)

elijahwald.com

Without any direct evidence (although it's an idea I picked up from attending various immunology lectures), it seems like aging/death is at least partially linked to immunity.

Our ancient ancestors had to make a tradeoff in order to combat the extremely high mutation rate of their microbes, by increasing their own rate of genomic diversity (through sex, and through adaptive immunity) including in the receptors which detect microbes.

Sexual reproduction https://en.wikipedia.org/wiki/Sexual_reproduction

V(D)J recombination https://en.wikipedia.org/wiki/V(D)J_recombination

Evidence of G.O.D.’s Miracle: Unearthing a RAG Transposon https://www.sciencedirect.com/science/article/pii/S009286741...

However, nothing is free, and with the ability to generate this extreme genetic diversity comes a higher risk of making mistakes including un-programmed DNA breaks, etc.. All these little mistakes add up as aging, and sometimes cancer, when the repair pathways are not able to keep up with the damage.

Also, by having an adaptive immune system you're constantly breeding tougher and tougher microbes, which could be considered harmful.

The acquired immune system: a vantage from beneath https://pubmed.ncbi.nlm.nih.gov/15539148/

Hence the importance of feeding your microbes in a predictable manner, with something that is not too easy to digest but calms them down so that they don't overrun the place.

Mucus acts as both a barrier and a food source with an extremely diverse O-linked glycans which decorate its backbone. ~800k permutations of the 5 possible O-linked if you consider a glycan chain of length 5, and 3 possible linkages types. In actually the diversity is likely greater given chain branching patterns, randomized expression of glycosyl hydrolases which generate the mucus, etc..

Not pc anymore but a lot of humor and insight. I got a kick out of why he thinks hungry animals run. Pretty sure he is wrong (there are often unexploited niches and opportunities) but it made me laugh.

> I used to think that way, too, but I don’t any longer. You see, every creature alive on the earth today represents an unbroken line of life that stretches back to the first primitive organism to appear on this planet; and that is about three billion years. That really is immortality. For if that line of life had ever broken, how could we be here? All that time, our germ plasm has been living the life of those singlecelled creatures, the protozoa, reproducing by simple division, and occasionally going through the process of syngamy -- the fusion of two cells to form one—in the act of sexual reproduction. All that time, that germ plasm has been making bodies and casting them off in the act of dying. If the germ plasm wants to swim in the ocean, it makes itself a fish; if the germ plasm wants to fly in the air, it makes itself a bird. If it wants to go to Harvard, it makes itself a man. The strangest thing of all is that the germ plasm that we carry around within us has done all those things. There was a time, hundreds of millions of years ago, when it was making fish. Then at a later time it was making amphibia, things like salamanders; and then at a still later time it was making reptiles. Then it made mammals, and now it’s making men. If we only have the restraint and good sense to leave it alone, heaven knows what it will make in ages to come.

>I, too, used to think that we had our immortality in the wrong place, but I don’t think so any longer. I think it’s in the right place. I think that is the only kind of immortality worth having -- and we have it.

If you take that line of reasoning, you might as well go further. The protons of the hydrogen atoms in your body are from seconds after the Bing Bang. They were there at the formation of gas clouds, and galaxies, and stars, and novae, and supernovae, and, the formation of our sun and planets. They were present even before the single celled organisms in the water, the methane, the precursors of nucleic acids and organic molecules. And, with an estimated half-life of 10^34 years, these protons will be around long after the all life on Earth is gone. Compared to them, the germline, is but a drop in the bucket.

Perhaps you're discovering monism

>> an estimated half-life of 10^34 years, these protons

As far as I know the proton decay is just a hypothesis - they may be able to exist forever. Usually particles decay into lighter particles, but there is no lighter particle that a proton can turn into while keeping it's electric charge.

We’re all stardust.

we're all stardust

anything that happened so far has been causal and mandatory

you are forced to read this

Very fascinating read. Reminds me of a recording of a stream I was listening to recently where the person talks about the idea of death being given in a deal to biological life.

Maybe immortal organisms did exist at one point. Issue is that being immortal prevents you as a specie to adapt to changes. Death of individuals can be simply seen as a competitive advantage within the framework of the theory of evolution.

The linked talk explains that death isn't necessarily related to adaptation. There are many advanced organisms that just keep splitting and don't die, unless eaten or something. Moreover, the part of ourselves that accumulates adaptations (the line of germ cells passed from parents to children) also keeps splitting and doesn't die.

Rather, the point is that at some point the immortal germ line found a weird trick: "let's make in each generation a bunch of cells that will help the germ line reproduce, but that won't themselves reproduce". Like sterile worker bees. And our body, including the brain, is a pile of just such disposable cells.

That’s right, thinking about your point, with cancer our cells still know how to turn immortal. But what’s the point if it’s at the expense of their carrier. I need to reflect on the implications.

If you follow Richard Dawkin’s reasoning that all organisms are just very effective DNA replication machines, this makes a lot of sense.

On the end a "competitive advantage" is a thing that helps to nicely explain a lot of things like vision, self-consciousness, feelings… Does nothing to the reason why Von Neumann machines appeared on our planet thought.

"The Selfish Gene" attempts to explain this, starting with self-replicating (IIRC) predecessors of amino acids in the primordial soup, which became more and more complex. It's been a while since I read it, so I don't recall details any more.

A great read, fascinating stuff

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