[nilkn]

It's been speculated for at least a decade now that geochemistry spawned biochemistry and life as we know it. This appears to be the latest instance of this pattern. One of the most notable examples is geothermal processes simply creating calm energy gradients that are stable for billions of years (e.g., underwater alkaline vents), which can then essentially "manufacture" organic compounds, which naturally assemble into more complex compounds like magnetic Lego blocks, which ...

I like to think of the Earth as a supercomputer running a vast self-interactive chemical computation of unfathomable scale for an unfathomably long amount of time. In this view, the Earth is roughly a ~10^38 ops/sec dissipative self-modifying search engine, of which life captures roughly ~10^35 ops/sec into metabolism, heredity, ecological competition, and evolutionary search. Once proper biological evolution kicked in, with some bumps along the road, it has had a general tendency to reallocate that immense compute capacity in a way that increases search adaptivity per joule by finding and stacking "search accelerators" (prebiotic geochemistry/biochemistry, replicators, cells, DNA/RNA/protein systems, mitochondria, sexual reproduction, multicellularity, nervous systems, intelligence / brains, language / culture, science / technology, ?).

[AareyBaba]

Yet, there is only one form of life on earth exhibiting cellular metabolism and DNA/RNA replication. That original life form formed as soon as the earth became suitable for life. In the 3+ billion years since, there has been no new life form created that we know of despite the ongoing unfathomable computations.

[nilkn]

That is not unexpected. There are three forms worth considering, actually: bacteria, archaea, and eukaryotes. The first two share DNA/RNA replication, but they operate in completely different ways. The third is dramatically more complex than either of the former two, yet emerged from them. Once the first two existed, they rapidly filled almost all possible niches available at that time, and there was no space for a third form to emerge (lest it be immediately consumed by the first two), unless that third form was exceptionally competitive (like eukaryotes were and are). The first two forms did emerge relatively early on. The third form, representing one of the most stunning advances in the history of life on Earth, took over two billion years of 10^35+ ops/second of continuous computation to emerge. In terms of total compute, that's about 10^25 greater than today's largest known frontier training run. After that point, evolutionary selection pressure began operating at higher levels of abstraction, selecting for complex multicellular morphological form and later on intelligence, culture, and beyond, over several additional billion years, while bactera and archaea continued to consume all available microscopic niches.

Beyond that, life itself modified the environment that produced the original process of abiogenesis. The early Earth featured a carbon-rich acidic ocean. After life emerged, metabolism began altering the planet’s redox chemistry, consuming available chemical free energy, transforming atmospheric and ocean composition, and eventually oxygenating the surface environment. In other words, the machinery that produced life was not left running in the same state. This is why I called it a self-modifying search engine -- search accelerants operate by changing the search landscape that the engine operates over.

[v64]

On 1 February 1871 Charles Darwin wrote about these publications to Joseph Hooker, and set out his own speculation that the original spark of life may have been in a "warm little pond, with all sorts of ammonia and phosphoric salts,—light, heat, electricity &c present, that a protein compound was chemically formed". Darwin explained that "at the present day such matter would be instantly devoured or absorbed, which would not have been the case before living creatures were formed." [1]

[1] https://en.wikipedia.org/wiki/Warm_little_pond

[mncharity]

"There's strikingly little agricultural innovation in this corner of France" they mused... as the ground shook from tanks and shrapnel bursts.

A glass of sea water seems so peaceful... with its turbulent combat hellscape of voracious protists and viral shrapnel, where you're lucky to make it through a day without being eaten or lysed.

[jfarlow]

Network effects + energetic fficiencies. On an energy landscape that includes integration over very short and very long lifetimes, the thalweg of utility/energy rests right about where the current codon optimizations are. And any schemes that deviate don't get to share in the others' bounty. Reusing your foods' effort saves a lot, metabolically.

[hanjeanwat]

Or, at least, our form of life outcompeted all others out there. We don’t actually know that life only started the one time.

[ceejayoz]

Well, yeah. Starting from absolute scratch is a lot harder than adapting something that already exists to new conditions.

[nlitened]

As I understand, earlier forms of life used RNAs as building blocks (instead of proteins encoded in DNA->RNA), so protein-based life _was_ a completely different form of life.

Some of the oldest replication machinery in our cells still uses the good old rusty RNA building blocks at its core (however nowadays they're propped up with proteins), and the newer machinery is almost entirely "high tech" proteins.

So you could say that in the billions of years, entirely new life forms were created, and they just completely displaced the older, less effecient ones. Probably pure-RNA life forms were not even the first ones, and they completely displaced even more primitive prior biotechnology when they appeared.

[tardedmeme]

This is, at this point in time, still a hypothesis.

[Shitty-kitty]

Any "new life" has 0 chance in the crowded, highly competitive ecosystem.

[fragmede]

Is that still the case with the discovery extremophiles that exist on chemical vents deep under the ocean and far away from the sun? Or rather, how sure are we that they're the same form?

[myrmidon]

Yes. All known life shares an (assumed) last common universal ancestor (LUCA, presumed extinct), and there is significant evidence pointing that way.

We can infer properties and function by looking at genes shared between archea and bacteria that most likely came from such an ancestor; this paints a picture of a DNA-based anaerobic thermophile (think hydrothermal vents) with a membrane and simple anti-virus defenses (CAS).

[IsTom]

If there were more they could have been outcompeted early.

[customguy]

Search for what though? On the face of it, life might also just be some eddies in the stream of energy flowing downhill, so to speak.

[dtgriscom]

> eddies in the stream of energy flowing downhill

"Ah... is he. Is he."

[jpm_sd]

there, behind that sofa!

[s1artibartfast]

Life isn't eddies, it is deepening the stream to paddle the boat.

We are entropy engines hastening the flow. For each bit of temporary order, we make two of disorder at the same time.

[lioeters]

> bit of temporary order

Isn't that what we call life? Or at least, life is part of that tendency toward anti-entropy which sounds strangely similar to creativity.

[mrsvanwinkle]

your name is all the most beautiful sounds in the world in a single word

[flir]

I don't know, but I'm pretty sure it's got something to do with laboratory mice.

[AlienRobot]

The answer to life, the universe and everything, I guess?

[philipallstar]

> I like to think of the Earth as a supercomputer running a vast self-interactive chemical computation of unfathomable scale for an unfathomably long amount of time.

Or "I read the Hitch Hiker's Guide to the Galaxy".

[eks391]

I almost agreed with your comment, but then I remembered there are countless planets with conditions unsuitable for life (as we know life). We have found a couple planets that are optimisticly closer to Earth conditions, but very few, and there is usually some characteristic that makes it a stretch still.

With that said, if Earth was compared to a super computer, the initial conditions and perturbations (weights and biases, or probabilistic inference) are very important, as most planets that are also performing ~10^38 ops/sec will never succesfully manufacture biochemistry/life.

[nilkn]

I've actually thought about this. My personal interpretation (which I admit is absolutely a bit playful, but I also find it very fulfilling) is that gravity acts like a resource allocator. It clumps matter together into stars, planets, etc., forcing it to interact, while keeping those objects far enough apart that they generally can run independently of each other for very long periods of time.

If you allow me to exercise some creative liberty with language, it's almost as if gravity is just launching countless trillions of parallel instances of the same computation, with nearly all possible initial starting conditions. Some of those initial conditions allow the local compute capacity to "descend" into finding more and more optimal ways to increase entropy and heat dissipation by exploiting local energy gradients (i.e., life).

In terms of the frequency of life, I'd expect basic microscopic life to be somewhat common, as it's "just" a way of exploiting geochemical energy gradients for local entropy maintenance. That doesn't necessarily even mean fully functioning cells, genetic codes, etc. It really just means molecular compounds or assemblies that exploit or create energy gradients. However, generally once that's kicked off, it's reasonable to consider that this generally would lead to the kinds of selection pressures that favor the development of what we'd know as basic cellular machinery and replication.

However, complex life I would expect to be almost vanishingly rare. The Earth only managed to figure it out a single time so far as we know (generating eukaryotes from bacteria/archaea) in billions of years. How many other planets feature roughly the same chemical computation which just never explored the right niche of chemical possibility to give rise to that complexity? This suggests to me the universe must expend unbelievably vast amounts of computation to overcome the threshold to complex life. I don't think it'd be unreasonable to assume that it requires thousands of separate "planetary computers", each with basic life, for only a single one to generate something like complex life (eukaryotes or equivalent), and that's to say nothing of the millions or billions of planets that don't generate any life at all.

[eks391]

You had me at

> gravity is just launching countless trillions of parallel instances of the same computation, with nearly all possible initial starting conditions

Great take and conclusion, no issue with the playful language here. It makes sense that, entropy being a required output with time, and 'infinite' near isolated cases would find just about every way to create that entropy, to include the efficiency at creating it (life, as you said).

Lovely take. Earth is a supercomputer. And to play on sibling responses to your first comment, this supercomputer is solving the answer to life, the universe, and everything. The answer is entropy though, not 42

[bigbuppo]

As Crime Pays But Botany Doesn't always says... botany is just applied geology, so it probably isn't a big stretch to extend that to the underlying chemistry.

[mncharity]

> stacking "search accelerators" ([...])

On my long-term todo list, is making a didactic simplified tree-of-life, compressed reflecting highly conserved microRNA families (perhaps also Hox clusters and TF transcription factor families) as a regulatory complexity budget, expanding and refining. Traditional presentations obscure the stacking, for example making primates seem just another mammal, instead of a "WTF happened there".

[rolisz]

So Douglas Adams was right and the Earth is a computer created to calculate the ultimate question?

[mjanx123]

> I like to think of the Earth as a supercomputer running a vast self-interactive chemical computation of unfathomable scale for an unfathomably long amount of time.

42

[matheusmoreira]

I really like the way you think.

[lazide]

The Buddha nods.