Comment by ramraj07 | Hacker News Reader

Comment by ramraj07 | Hacker News Reader

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It’s often hard to tell between a genius who’s so far out away from others that what they say doesn’t make any sense or someone who has no clue what’s actually known about something. I’ll give that benefit of doubt to you but suffice to say I have no idea what you’re talking about.

The rna hypothesis is not overhyped. The fact of the matter is rna looks like a likely candidate that can form in the conditions of early earth, and it’s a perfect candidate for a single molecule that can become self replicating. We don’t know the math of the probability that this thing happened and how big an experiment volume we had in terms of environment size and time span, so hard to tell if this happened this way or not. Suffice to say I see no other plausible hypothesis proposed that is as believable as the RNA world. At least something I can understand anyway.

FWIW I do believe in the RNA world hypothesis only I don’t think it happened in earth, but some other planet at some point in past. I just think that space is filled with floating frozen microbial spores that can instantly (geologically speaking) inoculate any planet with the right conditions.

Not the GP but maybe I can help elucidate the position they're representing. The GP advocates for what is known as the "metabolism-first" hypothesis in origins of life theory. The motivation of this theory that some chemists and biologists find it implausible that a self-catalyzing RNA based biological machinery would have formed spontaneously from a collection of basic precursor chemicals, even given very long spans of time and large volumes of precursors. They believe this because nucleic acids are very complex structures and themselves require very complex biologic machinery to assemble, and their understanding of the likelihood of chemical reactions suggests its unreasonable to expect them to form in geological time spans. They posit that instead its more likely that nucleic acid based systems were themselves preceded by system(s) composed of sets of simpler chemicals (ones which are likely to form spontaneously) which together catalyze each other's formation (a so-called "auto-catalytic set"), and that this era of simple metabolisms eventually produced a nucleic acid based system which completely overtook and replaced/assimilated the more primitive auto-catalytic set world.

Here's a primer on the metabolism-first hypothesis: https://www.statedclearly.com/videos/what-is-the-metabolism-...

Thanks for the reference. As the other commenter mentioned, this is great research but I don’t see it as with odds with a molecule of RNA being the first living thing ever. We didn’t discuss before what powered these RNA molecules, but clearly this research is showing us one aspect of it (preexisting metabolic pathway like reactions). These systems might be considered as evolving the same way the sun is evolving I suppose? In the end I would classify life as something that has encoded information on how to create itself and the machinery to do it (or at least the means to recruit the machinery and raw materials) and actually propagate itself perpetually in the right conditions. RNA is still the only viable candidate for that.

RNA first is about stored heritable genetic information? At least I've not met anyone who's in some hardline way RNA miraculously appears and starts creating the auto catalytic networks second. How does the RNA appear? Slowly at random from nothing? Why would anyone think this, it doesn't pass thought experiment level parsimony. The reason to highlight RNA first is because if you just looked at whats alive now you might assume DNA is the older molecule in use as its the primary store of genetic information for most things alive right now. The big idea is that it wasn't. That doesn't mean everyone means its the first molecule to exist in the history of molecular life...

because RNA is used in more old clade of tree of life. DNA is a younger character in history

what I'm saying is,

RNA, great, that's a Thing. I just don't think that finding a mechanism for RNA to arise is the big step. I think the Big Step is going to be discovery of a set of molecules that use what's available to make more of that set.

Could the molecules in that set be RNA? Sure! Do they have to be RNA? I have no idea. How small can that set be? Can it be a single molecular species? That would be fascinating! I'd think it would probably take more than one, though.

I'm not trying to rain on anyone's parade, just trying to stir the pot of ideas.

So wait, you think there could be a potentially simpler system than a SINGLE MOLECULE OF RNA that is self replicating (I.e. if all you provide is a chemical solution with the raw base ingredients it can build more of itself with no other help)? That’s awesome. Please share, no hyperbole intended, what your hypothesis is.

But that doesn’t change the fact that RNA world fits the most amount of our observations. I already described proving it’s plausibility in our experiments. On top of that please don’t forget that ribosomes, the complexes that produce proteins in our body, are mostly RNA, and the rna part is the primary enzymatic system in it. That is, we actually have a vestige of a system where rna ruled the world.

I’m not even asking you for proof, I’m asking you to even put forward an actual molecular system that you think is better suited to explain this than rna.

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