The origin of life remains a profound mystery. The more we investigate, the further we push back its beginnings, suggesting that we may eventually need to search beyond Earth for answers. Since the Miller-Urey experiment, which successfully synthesized amino acids, we have made little progress in understanding the exact processes that led to the emergence of life. How were RNA and DNA formed? How did the first cell come together? What were the necessary timelines, energy sources, and chemical conditions? Is Earth uniquely capable of generating life, or is life, in its most basic form, a common feature of the universe? The formation of water involves processes akin to supernovae; perhaps the genesis of life requires a similarly extraordinary scale of events, or even more? We need to find out.
This sounds a bit defeatist, and seems to ignore a large swathe of work that has happened since 1952 (the Miller-Urey experiment).
For example - this experiment was conducted a year before the structure of DNA was discovered / published - so it's quite a bold claim to say 'origin of life' research stalled in 1952.
To your first, second, and third questions - I can highly recommend Nick Lane's book 'The Vital Question' [0]. To some extent, I think he also spoke to your fourth question in that book - but I read 3 or 4 of his books around the same time, so my memory is fuzzy.
Either way, his hypothesis around alkaline thermal vents is hugely persuasive & compelling.
I'm really struggling to understand what you mean by the claim 'formation of water involves processes akin to supernovae' - do you just mean you need a star to explode before you get heavier elements (including Oxygen)?
I completely understand your struggle and wonder why this fact isn't more widely discussed. The vast majority of water on our planet (and in the solar system) was formed through either stellar formation or supernova events. During these events, an outward wind of particles collides with nearby material, forming new molecules such as water. Any other process of water formation is negligible in comparison.
There's no reason to think other solar systems wouldn't have water, in that case, as there's little that's unique about our garden - or, from a slightly different angle, we shouldn't be surprised to find ourselves living in a place that has water.
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.
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:
A little bit of a side here, but I'm impressed with the page's presentation. It's a university website, but the layout and overall design is really polished. Great work.
The presentation has one of the most annoying things I know, it quotes itself. And it quotes a lot. It is like watching sports game when commentator says you that there will be a home run in a while, and the final game score will be such and such. You lose all the intrigue of the game this way.
This one is particularly egregious. It has a quote, then a few lines down (if not the line immediately after, like in the first case) has a paragraph which is just the quote. Why is it making us read the same thing twice in a row?
This has become a pervasive journalistic practice, and I am mildly curious as to why. Has it been found to encourage a subset of readers to keep on reading, and maybe become subscribers? Maybe some readers routinely scan these teasers to decide whether they will read the article. Is it a form of SEO? (I would guess not, but it's not my field.)
It is almost as if some junior editor (or LLM, though I think this practice predates them) has been given the job of dividing the article into sections with headers, but can't be trusted to use their own words for the headers (though they can still, of course, both divide and quote out of context.) Here, this appears to have been applied after someone else (the author, perhaps?) had already divided it into sections with traditional summaries for headers.
That said, I felt this article is much more engaging than the average university press release, and presents a genuinely significant discovery without, as far as I can tell, another now-commonplace annoyance: the excessive exaggeration or misrepresentation of that significance (though one might quibble over "...and could rewrite our timeline of complex life on Earth altogether.")
I should have known that, as I have been reading magazines for decades, so the question now (for me) is why I have only recently found them to be intrusive - is it me that's changed?
I think it's more annoying when the quote is (more or less) directly before the actual same text (like here). As such, it has no helpful function for the normal reader - it's only annoying (but might help the skim reader or rather only the "scroller" who doesn't really read). Whereas in magazines it was that you opened the page and looked at those few quotes and decided whether you wanted to read the text, in that way the quotes are not really annoying imo.
Does anyone know the smallest features preserved by fossils? For example, would cellular machinery like the ribosome be preserved? The shape of DNA? (Both assuming this cell had these)
> A microfossil is a fossil that is generally between 0.001 mm and 1 mm in size
Which is a bit vague, but 0.001mm is 1000nm while a ribosome is in the range of 20-30 nm diameter. So a whole ribosome is around a 1/50 below the lower end of the microfossil range.
Even though DNA can be a lot longer (1000 base pairs is 3.4 nm - I think? - so a hundred kilobases would be 300-400 nm) the atomic features are too small to fossilise would be my guess.
