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Comment by maitola | Hacker News Reader

On the contrary, I don’t want to sound defeatist. We’ll figure this out sooner or later, and it’s actually quite exciting, after all, we didn’t just come from a little pond! The discovery of DNA, RNA, and many other cellular mechanisms has greatly improved our understanding of how life works. This knowledge helps us formulate theories about the origin of life. However, as of today, no one has, for example, taken a Miller-Urey like experiment and spontaneously generated DNA.

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Well if RNA was a (necessary) precursor to DNA, some experiments that attempt to replicate aspects of a deep alkaline thermal vent have already been conducted - you can get, albeit very short, strings. But the obvious problem is in trying to replicate a chemical soup and structure under high pressure, that doesn't exist any longer, and then run experiments to try to replicate outcomes of a natural experiment that lasted hundreds of thousands of years.

The idea that DNA needs to be spontaneously generated in order for us to be confident that we understand how DNA came to be is misplaced.

The point is that until we understood stellar mechanics and observed the formation of water in stellar events, we didn’t know where water originated. This suggests that we should not limit our thinking to Earth-based mechanisms when considering the formation of RNA and DNA, which are molecules orders of magnitude more complex than water.

Another problem is that the earliest fossils are 4.3 billion years old, while Earth itself is 4.6 billion years old. This means that life must have originated within the first 300 million years of Earth’s existence. What was this unique environment that enabled the creation of RNA, DNA, and cells? And why did this magical environment disappear in the subsequent 4.3 billion years?

We don't need to generate it spontaneously, but we do need to understand the mechanism precisely. Filaments alone (can you share the relevant research on this?) are not enough.

We need to understand exactly how DNA, RNA, and cells came into existence, just as we sought to understand the formation of water. Until then, we won't have the answer to the origin of life.

Sure, the problem of having a sample set of precisely 1 makes it dangerous to extrapolate too wildly ... but similarly, the absence of any other type of life on this planet, and our understanding of - and ability to postulate on - other building blocks viability, should not be dismissed because a carbon / water / oxygen arrangement is known to work.

I think you'll really enjoy The Vital Question, as it covers a lot of what you seem to be interested in knowing more about.

> Another problem is that the earliest fossils are 4.3 billion years old ...

I thought the figure was a bit less that that - and referred to (disputed) indicators of life, not fossils per se, but the generally agreed upon earliest is dated at ~3.5bya.

Nonetheless your point is understood -- some basic building blocks appeared 'spontaneously' over the space of 800,000 years, give or take.

Conditions at the time are broadly understood, though of course not the details - and it's that ~ 800,000 years, plus the unknowable details of the environment, that make me think we'll never know for sure.

At least not in the level of confidence that you appear to need - where the precise chemicals, with the right ratios, in the right solution, at the right pressure/depth, making whatever the first life form was (we don't know what that was, and likely can't ever know).

Ultimately I don't think we need to know exactly how DNA, RNA, and cells came into existence - it'd be nice, sure, but there's no requirement for that likely unobtainable goal.

Regarding filaments - I just searched on 'hydrothermal vents rna' and found a few likely links, including this one:

https://astrobiology.nasa.gov/news/lifes-building-blocks-for...

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