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It's a remarkable thing to step back for a second and realize that while we try to figure out the exact impact of a parts-per-million change in CO2 concentratio
by andrewla 2y ago
It's a remarkable thing to step back for a second and realize that while we try to figure out the exact impact of a parts-per-million change in CO2 concentration, that it's astonishing that CO2 is not 20% of the atmosphere, that the only thing keeping O2 in the atmosphere at all is the large-scale actions of living things. [1]
The fact that living organisms are responsible for something so large seems almost dumbfounding -- planets are big, atmospheres are big, and life is small; what is a pool of algae compared to a mountain, etc. But even such a basic thing as "the only reason we can have something as fundamental as FIRE is because of living things" is a bit of a mindblowing realization.
[1] probably not literally true; if you eliminated all life on earth then most of the O2 would probably be sequestered in oxides rather than remaining resident as CO2, but still. Although I guess a lot of non-living organic matter would eventually burn away as long as there is oxygen to support combustion.
- throwaway290 2y ago> The fact that living organisms are responsible for something so large how do you separate living and non living things? (https://en.wikipedia.org/wiki/Life#Challenge https://en.wikipedia.org/wiki/Life#Challenge) everything is responsible for something.
- exe34 2y agoThey meant puny gooey things.
- throwaway290 2y agoYes, I figured that's about the level of sophistication:)
- exe34 2y agoIt was a poetic reflection. Don't worry, I didn't always get this sort of thing either. Maybe one day you too will learn to enjoy it :-)
- throwaway290 2y agoThe goal was to move from empty poetry to actually interesting science oriented discussion. Maybe one day you learn to enjoy those ;)
- exe34 2y agoI'm currently reading Biological Science by Scott Freeman on my day off, and later on I'll finish off Special relativity and classical field theory by Leonard Susskind. If you consider poetry empty, perhaps it is you who are missing out on something. I myself do enjoy both ;-)
- throwaway290 2y agoNot all poetry is empty, but some poetry is empty Good on your reading progress, now all that's left is to engage in interesting conversations about those topics;)
- exe34 2y agoI'm quite picky on whom to engage in interesting conversations with.
- throwaway290 2y agoSame except I guess the difference between us is that I am picky regarding substance (what it is about) not whom it is with.
- jmcqk6 2y agoI'm pretty sure it is literally true that the oxygen in the atmosphere is there only because living things keep putting it there. You're right that without life, it would be sequestered in oxides pretty quickly. That's the local minima for energy dissipation. Life is good at breaking those minimas for cyclic matter dissipation. If there was a natural source for oxygen, it would have to come from some sort of cycle in order to be maintained, and there's not a energetically favorable cycle for that. It's why it makes a good biomarker when looking at exoplanets. If we find an exoplanet with high amounts of oxygen in the atmosphere, we can be fairly confident
- patcon 2y agoWas much more likely true until a week ago, but now there’s a legit competing hypothesis :) https://www.nature.com/articles/s41561-024-01480-8 https://www.nature.com/articles/s41561-024-01480-8
- jmcqk6 2y agoYeah, that's an exciting discovery. I was excited by this, because I believe it demonstrates a dissipative pathway that could have contributed to abiogenesis. Energy gradients are a driver of emergent complexity.
- robwwilliams 2y agoYep, exactly what I thought when reading Lane! But what would be the quantitative contribution of benthic O2?
- robwwilliams 2y agoI’m surprised by this statement. Here is a quote from Nick Lane’s great text: Power, Sex, Suicide (p 153): > The early Earth, as envisaged by [Michael J] Russell, is a giant electrochemical cell, which depends in the power of the sun to oxidize the oceans. UV rays split water and oxidize iron. Hydrogen, released from the water, is so light that it is not retained by gravity, and evaporates into space. The oceans become gradually oxidized relative to the more reduced conditions of the mantle.” Lanes cites this paper “On the origins of cells: A hypothesis for the evolutionary transition from abiotic to nucleated cells”, 2003, by Martin and Russell https://pubmed.ncbi.nlm.nih.gov/12594918/ https://pubmed.ncbi.nlm.nih.gov/12594918/ Am I missing something? This text forces me to assume that solar UV splitting water is the cause of the O2 atmospheric flooding.
- SideburnsOfDoom 2y ago> planets are big, atmospheres are big, and life is small; And time is long. The consensus is still that the oxygenation of Earth's atmosphere took "at least 400 million years". A lot of that is due to the "great rust", i.e. minerals that would take oxygen out of the air had to first exhaust their capacity to oxidise. This took "nearly a billion years". Iron ore deposits are from the seabed of this period. See: https://en.wikipedia.org/wiki/Great_Oxidation_Event https://en.wikipedia.org/wiki/Great_Oxidation_Event https://en.wikipedia.org/wiki/Banded_iron_formation https://en.wikipedia.org/wiki/Banded_iron_formation
- pfdietz 2y ago> Iron ore deposits are from the seabed of this period. Many are, but some are more recent. https://en.wikipedia.org/wiki/Chilean_Iron_Belt https://en.wikipedia.org/wiki/Chilean_Iron_Belt https://www.nature.com/articles/s41467-023-43655-8 https://www.nature.com/articles/s41467-023-43655-8
- tambourine_man 2y agoThat was pretty interesting to me and perhaps changes our idea of how the great oxidation went a bit: (Evidence of dark oxygen production at the abyssal seafloor) https://www.nature.com/articles/s41561-024-01480-8 https://www.nature.com/articles/s41561-024-01480-8
- BestHackerOnHN 2y ago> "the only reason we can have something as fundamental as FIRE is because of living things" is a bit of a mindblowing realization. I am fairly confident living things did not create FIRE.
- andrewla 2y agoWell, we (broadly speaking) did not create the concept of a plasma phase of matter, but fire as we know it is only possible because of free oxygen. Fire, for the most part, is just another name for rapid oxidation. Even some things that can burn without air (e.g. magnesium) typically only burn because they are so hot that they cause H2O to separate. Obviously stars exist, so there are other ways of getting to plasma, but oxygen is what makes terrestrial fires possible. So yes -- living things created fire!
- kadoban 2y ago> Even some things that can burn without air (e.g. magnesium) typically only burn because they are so hot that they cause H2O to separate. I'm not positive about magnesium, but also most of them only burn because we've converted them to materials that don't exist in nature. Eg it'll only be found as oxides (ie already burnt) and then we put some energy or chemicals in to get the form we want. If it _can_ oxidize as found in nature, there has to be some good reason it didn't already do it over ~billions of years.
- wrycoder 2y agoBare rocks and water don’t burn, they are already oxidized. Life chemically reduces CO2, providing material than can support combustion.
- bregma 2y agoWell, we didn't start the FIRE. It was always burning since the world's been turning.
- solardev 2y agoWithout living things, who would retire early? The markets aren't going to trade themselves.
- Teever 2y agoLet me share a twist on this train if thought that I've had recently. The nature of the Earth's atmosphere, surface, oceans, and much of the subsurface is entirely the product of a single cell. A single cell lead to more cells which eventually evolved into different forms and became multicellular and so on and so forth until the earth was covered in all kinds of shapes and sizes of life and the landscape was permanently changed. All that from one cell. You and I are composed of trillions of these things and we're able to do incredible things with them, but at the same time our power is much more limited than that of the single cell that created all of life. We can do incredible things with our bodies but we lack the ability to completely control even a single cell in our body. As such a single cell can go rogue and kill you with cancer, or despite your best efforts to nourish, heal and exercise your cells you will eventually die. Imagine if it wasn't so. Imagine if you could control but a single long lived cell in your body. What could you do with that? Anything. Nothing could stop you. You could travel to the deepest depths as a whale or soar to the highest heights as an eagle. You could spawn a mass organism larger than Pando, or evolve something novel that would go to space. So imagine if someone locked you deep in a dark prison in solitary confinement and you could through something akin to meditation come to control a single cell in your body. No prison could hold you. What happens when we achieve mastery over ourselves in such a way through technology? Will we allow individuals this level of control over their own cells? Can we stop them?
- chiggsy 2y agoThis reminds me: Stem cells. Whatever happened with that?
- joshuahedlund 2y agoOh, lots. We are slowly but steadily making more advances with learning how to reprogram cells and get those cells to grow and divide and turn into things are sort of like different body parts. It's not really like sci-fi yet but it is honestly starting to get a bit weird. See the new book The Master Builder by Alfonso Arias for some recent info.
- feoren 2y ago
- BurningFrog 2y agoIf you kill all life on earth, I assume all dead biomass would oxidize into CO2. Though I'm not sure what processes would do that. Without microorganisms, nothing rots. Lightning would eventually burn down most forests, but maybe everything else would just lie where it fell for ever.
- restalis 2y ago"Without microorganisms, nothing rots." That is not (quite) true. The lifeless bodies of flora and fauna won't rot, but they will decay. Macro-molecules (like proteins), the basis for all life, are fragile and easy to break down due to a range of physical causes, most likely of which is just the non-cryogenic temperature. Smaller organic molecules are more sturdy and will last longer, but in the long term they'll end up under heavy layers of sediments and turn to fossil fuel (coal & oil).
- BurningFrog 2y agoThat makes sense, but I don't think much of the broken down molecules oxidizes. Which is also what "turn to fossil fuel" implies.
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- tracerbulletx 2y agoSome of those mountains are made of calcites and dolomites and bioturbated with trillions of miles of burrowing shrimp tunnels. The Biosphere is certainly as significant a process as any other process acting at or near the surface of the earth.
- m463 2y agoThe idea in my head is that life is anti-entropy. Maybe my idea is wrong? maybe it just has different signatures at different times?
- timschmidt 2y agoOne definition I've ever heard for life is that it's a process which increases the entropy around itself in order to decrease the entropy within itself. It disorders the world around it to order itself.
- m463 2y agothat might be true. And maybe lower life forms are destroyed to create higher (much less entropic) life forms.
- timschmidt 2y agoNearly all life gets consumed by some other form of life eventually. Often it's the bacteria and fungi and insects doing the consuming of what we might consider more sophisticated organisms. The negative entropy - all the useful molecules concentrated and precisely ordered - can be seen as the thing being consumed. Same goes for chemical or energy gradients like around deep water thermal vents or photosynthesis.