A rock that might hold the oldest form of complex life on Earth(news.unsw.edu.au) |
A rock that might hold the oldest form of complex life on Earth(news.unsw.edu.au) |
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)?
https://en.wikipedia.org/wiki/Water (see Distribution in Nature) https://web.archive.org/web/20000116054013/http://www.news.h...
Thank you for the books recommendations, I’ll check them out.
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.")
From https://en.wikipedia.org/wiki/Microfossil
> 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.
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.
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.
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.
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...