1. Autocatalytic RNA reaction networks -- "soup producing more soup" -- are easily replicated in the lab, subject to Darwinean processes, and are at the center of ongoing study. "0 to Darwin" is now easy, "Darwin to Life" is the new focus, and God of the Gaps must retreat once again.

2. Spores hitchhiking on impact ejecta sounds exotic until you realize that anywhere life is present at all spores will be everywhere and extremely sturdy. That desktop wallpaper you have of planets crashing together and kicking off an epic debris cloud? Everything not molten is full of spores.

3. Religious explanations are not in the same universe of seriousness as 1 and 2. Opening with a religious talking point and closing with a false equivalence is mega sus.

Good news: the primordial oceans were so vast (literally planet-scale) and persisted for so long (millions to billions of years) that you can run a trillion trillion individual random reactions.

You are being severely restricted by your imagination. You seem to have presupposed that random abiogenesis is impossible and reconstructed the facts to support that claim because you can't conceive of the alternative.

Planets are really, really big. Any one chemical reaction is on the scale of molecules. If you let those figures compound for a long time, the number of total reactions gets very, very large. Far larger than you imagine. Many times more.

>Still far, far too complex to occur "randomly," which is fascinating

I don't see the word "random" anywhere in the article. By random maybe you mean it's seemingly indeterministic? Regardless of the nature of the underlying process, at the classical level, the environment acts as a deterministic filter, ie, other chemical processes.

If you’re interested in this area I highly recommend “The Vital Question” by Nick Lane if you haven’t read it.

The TLDR of his theory is that life originated in alkaline hydrothermal vents on the ocean floor, where natural energy gradients could have driven primitive metabolic reactions before the development of DNA.

Book goes into a lot of layperson-accessible detail.

> Still far, far too complex to occur "randomly," which is fascinating

Why spend time making this point? Nobody believes that this occurred randomly: it occurred via evolution.

The mutations are a random part of evolution, but the process overall is not random at all - no more so than your immune system (which randomly generates antibodies, then selects against those that target innate epitopes), or stable diffusion (which starts with random noise, then marches up a gradient toward a known target).

It is the selection step that makes similar processes non-random, because a random selection step would just be noise.

So in this sense then, human beings themselves are obligate metabolic parasites on the planetary ecosystem, particularly on other life forms (plants, animals, microbes). The term "parasite" here is used in the metabolic sense of relying on another organism to produce essential compounds one cannot produce oneself. The molecules we must obtain fully synthesized from our diet are called essential nutrients. And for a Sukunaarchaeum, everything is an essential nutrient.

Are there any animals which don’t need components from another organism? Isn’t heterotrophy one of the notable attributes of Animalia? There are the infamous sea slugs which eat algae then use the algae’s photosynthetic chloroplasts to photosynthesize the chemical energy they need, but they still need the algae to make those chloroplasts.

As I understand it, it's not so much that they got "hung up" on some specific capabilities for theoretical reasons, but that it's rare to find cells without these capabilities. In other words, it's nature that seemed so "hung up" on these things.

We can survive without a constant stream of incoming raw materials. I wouldn’t think that makes us any less alive. Nor are we a parasite on the food.

Isn't methylation more like temporary variables?

Well tell them to quit playing with the stun gun.

No life exists "by themselves". Self-replication means using only its own DNA and not mangling with other's. Virii are not only parasites but dead matter (a ribonucl molecule surrounded by proteins that happens to stick to other cells, like dirt on the skin). Gut microbioma is parasite.

There is another life property that this object does not fulfill and is called Teleonomia, that is governed by an ultimate goal.

First, context: a "life/not-life" distinction is far more "science" than science - widespread in "science" education, but rarely comes up in science research. (Might be interesting to create a list of similar?) Why the emphasis there... I don't know - perhaps because we teach by memorizing definitions and lists, not by learning design spaces and their landmarks? Or at least by giving exemplars without characterizing variance.

One of the few places I've seen it come up in science, was ecosystem multi-scale simulation software. Where virus was squarely in the heritable characteristics under selection pressure ("life") bucket, rather than abiotic or biogenic.

Informal "do you think of viruses as alive?" seems to vary by field. I've seen a marine bio labs be overwhelmingly yes. I've been told medical immunology leans no. But it seems more social-media engagement question than research question or synthesis.

Viruses are considered infectious agents rather than life forms per se.

<https://en.wikipedia.org/wiki/Introduction_to_viruses>

def not life. there is no sense in which a virus... 'does' anything, it's not agentic. it's kind of like a free-floating loaded spring.

It is a question in philosophy. It is the difference between being considered a conscious being, and not. Since for now our definitions of a conscious being is tied to being alive (when is a human alive and not death?). So obviously it has implications on ontological questions. It fundamentally limits our understanding of what exists and just as important, why we exist.

It's like the word "planet", ultimately a tired game of definitions.

Yeah, I should have mentioned that. Article about the same topic and preprint, but released earlier this year.

How do any of those things fit that definition?

No, none of those can mutate, that's the point of "and mutate heritably"

Crystals can "reproduce", but it's always the same (there can be errors, but they don't inherit), so they don't count.

And atoms don't reproduce, so I'm missing your point there.

Then where are they getting the materials to replicate? Where are they getting the energy? Magic? No, they're pulling pre-metabolized materials and energy from the host.

I don’t think a precise definition of life is particularly important or of particular interest to most biologists. This thing is life in the sense that it’s definitely in scope of being studied by biologists (same is true for viruses, of course). And the reason it is speculated that it may be crucial to understanding life is mentioned in the article: “This organism might be a fascinating living fossil—an evolutionary waypoint that managed to hang on.”

Eh, you're quibbling with words. We're getting closer to the quantum (indivisible) definition of life, and that's understanding.

An interesting counterpoint to how little we know, and/or how useless in practical terms our quantum level understanding of physics is, is chemistry.

Chemistry is adjacent to physics, at least classical physics and the standard model, so you might think that we should be able to use our knowledge of physics to determine things like atomic bond "angles" and the protein folding problem, yet even this smallish step up in abstraction from physics puts us in a realm where we know very little. DeepMind's AlphaFold, now able to correctly predict 90% of protein folding in agreement with experimental determination, is mostly based on learning from experimental data, as well as evolutionary consideration of proteins that co-evolved, etc.

It makes you wonder how useful the reductionist model really is in terms of understanding higher level dynamics. Maybe different levels of abstraction like physics, chemistry, etc, are really a lot more independent than is commonly thought.

Maybe better to say "We understand enough physics to model all the possible interactions PHYSICS might have on this planet".

There are many levels of abstraction between quantum/particle physics and life, or even just cosmology (things like dark matter, etc), that we really know very little about.

Please avoid generic tangents and political/ideological battle on HN.

https://news.ycombinator.com/newsguidelines.html

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Only if it has a mechanism to send signals into the host and cell. For the CEO metaphor to hold, I'll accept that these signals can be entirely ignored, but they need to be transmitted.

I definitely choose the second of your two outcomes. That it includes all sorts of things that you think are not meaningfully alive. But these things are actually life.

Yes, living things locally decrease entropy and that’s my point.

And maybe I should’ve been more clear for people who cannot grasp new understandings, anything that can decrease its own entropy is living.

I mean, do you think life has nothing to do with the organization matter into a lower entropy state?

Water does not decrease its own entropy. If you can’t understand the distinction I’m making then you do not have the imagination and creativity to create new understanding.