Let's create an alien biosphere!

[Schiaparelliorbust]

They'll probably complexify gradually.

What might they start as?

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What might they start as?

There are many possibilities. One possibility is glycerol.

[Schiaparelliorbust]

There are many possibilities. One possibility is glycerol.

That sounds good to me. I guess the reaction would be 6CO₂+8H₂O→2C₃H₈O₃+7O₂

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hat sounds good to me. I guess the reaction would be 6CO₂+8H₂O→2C₃H₈O₃+7O₂

That's one possibility. Another would be 3CO+4H₂O→C₃H₈O₃+2O₂.

[Schiaparelliorbust]

That's one possibility. Another would be 3CO+4H₂O→C₃H₈O₃+2O₂.

Could they use both? There is more carbon dioxide (17%) vs carbon monoxide (6%), and after there is enough oxygen in the atmosphere there won't be nearly as much of the latter, so they might end up using my reaction exclusively even if they start with yours or both.

[MathAndCode]

Could they use both? There is more carbon dioxide (17%) vs carbon monoxide (6%), and after there is enough oxygen in the atmosphere there won't be nearly as much of the latter, so they might end up using my reaction exclusively even if they start with yours or both.

They could use both, but they'd probably evolve to use carbon monoxide first.

[Schiaparelliorbust]

They could use both, but they'd probably evolve to use carbon monoxide first.

I guess they would do that because it's simpler.
So we have
CO+H₂O→CO₂+H₂
HCN+NH₃→N₂+CH₄
CH₃NO+HNCO→N₂+CO₂+CH₄
3CO+4H₂O→C₃H₈O₃+2O₂ (which will eventually become 6CO₂+8H₂O→2C₃H₈O₃+7O₂)
H₂SO₄+CH₄→CO₂+2H₂O+H₂S
You called these two more likely than the one before:
HSO₄⁻+CH₄→CO₂+2H₂O+HS⁻
SO₄²⁻+CH₄→HCO₃⁻+OH⁻+H₂S
Am I missing anything?

[MathAndCode]

Am I missing anything?

Other possible reactions include 2CO→CO₂+C, CO+H₂→H₂O+C, CO₂+2H₂→2H₂O+C, 3H₂+N₂ → 2NH₃, and some analog of the reaction by which the giant tube worm symbiotes use sulfite to recharge ATP.

[Schiaparelliorbust]

Other possible reactions include 2CO→CO₂+C, CO+H₂→H₂O+C, CO₂+2H₂→2H₂O+C, 3H₂+N₂ → 2NH₃, and some analog of the reaction by which the giant tube worm symbiotes use sulfite to recharge ATP.

Good. Should we now see what happens when oxygen enters the atmosphere?

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Good. Should we now see what happens when oxygen enters the atmosphere?

I think that we should create at least a basic outline for the initial history of life before that. For one thing, we should keep track of which substances are building up and which are getting depleted. Also, we should figure out plate tectonics and ocean currents so that we can gain a sense of which reactions will become dominant where. For example, I suspect that reactions involving nitrogen-containing molecules that are abundant in the atmosphere but not produced by hydrothermal vents, such as HCN+NH₃→N₂+CH₄ and 3H₂+N₂→2NH₃, will be more popular in colder water because it can dissolve gases from the atmosphere more readily.

[Schiaparelliorbust]

I think that we should create at least a basic outline for the initial history of life before that. For one thing, we should keep track of which substances are building up and which are getting depleted. Also, we should figure out plate tectonics and ocean currents so that we can gain a sense of which reactions will become dominant where. For example, I suspect that reactions involving nitrogen-containing molecules that are abundant in the atmosphere but not produced by hydrothermal vents, such as HCN+NH₃→N₂+CH₄ and 3H₂+N₂→2NH₃, will be more popular in colder water because it can dissolve gases from the atmosphere more readily.

Ocean currents are easy enough. I will try and use GPlates for the tectonic plates. ( I forgot to learn it. Sorry.). I was thinking along with the supercontinent we could have a smaller island continent about the size of Australia. The supercontinent would later split into at least two pieces and one of them would collide with the island continent.
As for the substances, we could probably update them as we go along. Right now oxygen is certainly going up, and carbon monoxide and dioxide are going down. The latter will probably be at most several thousand ppm soon. Would other things that life uses go down (like ammonia, though they also produce it)?

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Ocean currents are easy enough. I will try and use GPlates for the tectonic plates. ( I forgot to learn it. Sorry.). I was thinking along with the supercontinent we could have a smaller island continent about the size of Australia. The supercontinent would later split into at least two pieces and one of them would collide with the island continent.
As for the substances, we could probably update them as we go along. Right now oxygen is certainly going up, and carbon monoxide and dioxide are going down. The latter will probably be at most several thousand ppm soon. Would other things that life uses go down (like ammonia, though they also produce it)?

Artifiexian also has a video about plate tectonics that might be helpful. I'd like to have a chain of hydrothermal vents so that early life can spread along them. Preferably, either the chain would vary in depth or part of it would gradually get raised closer to the surface by geologic activity so that the creatures would be encouraged to evolve for surface-dwelling, which will allow photosynthesis, but that doesn't have to happen right away.
I'm thinking that the first reaction that the organisms will use could be CO+H₂O→CO₂+H₂, followed closely by reactions that use the hydrogen, specifically CO+H₂→H₂O+C and/or CO₂+2H₂→2H₂O+C. The elemental carbon will accumulate outside the organisms, and the heat from the hydrothermal vents will trigger the reaction CO₂+C→2CO. The organisms will then develop the reverse, 2CO→CO₂+C. What do you think so far?

[Schiaparelliorbust]

Artifiexian also has a ocean about plate tectonics that might be helpful.

Thanks! I didn't watch that one yet. (Also, I think you meant video.)

I'd like to have a chain of hydrothermal vents so that early life can spread along them. Preferably, either the chain would vary in depth or part of it would gradually get raised closer to the surface by geologic activity so that the creatures would be encouraged to evolve for surface-dwelling, which will allow photosynthesis, but that doesn't have to happen right away.

Where do you want this chain to be relative to land? I don't think it would matter too much though it would probably be on the boundary of two oceanic plates.

I'm thinking that the first reaction that the organisms will use could be CO+H₂O→CO₂+H₂, followed closely by reactions that use the hydrogen, specifically CO+H₂→H₂O+C and/or CO₂+2H₂→2H₂O+C. The elemental carbon will accumulate outside the organisms, and the heat from the hydrothermal vents will trigger the reaction CO₂+C→2CO. The organisms will then develop the reverse, 2CO→CO₂+C. What do you think so far?

I like all of those. I had said earlier that maybe they could develop graphite shells. I also bet a good deal of the carbon would accumulate in the environment. What would happen to that?

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Thanks! I didn't watch that one yet. (Also, I think you meant video.)

Yes; I have fixed that.

Where do you want this chain to be relative to land? I don't think it would matter too much though it would probably be on the boundary of two oceanic plates.

Yes, it doesn't matter too much.

I like all of those. I had said earlier that maybe they could develop graphite shells. I also bet a good deal of the carbon would accumulate in the environment. What would happen to that?

The heat from the hydrothermal vents would likely turn some of it into carbon monoxide. The rest would likely settle on the seafloor, coating it a glistening back. It's possible that some of it would likely start to react with elemental hydrogen, producing methane. It's possible that one species will start taking advantage of that reaction as an energy source. However, the carbon will likely predominantly accumulate downcurrent and fairly far from the hydrothermal vents (or else the heat would cause it to react with the carbon dioxide), so those organisms would not be able to rely on hydrogen from the hydrothermal vents or the organisms near them. While there would be some carbon monoxide dissolved in the water, its levels would likely be lower farther away from the hydrothermal vents, so the organisms might face some pressure to develop another way to produce elemental hydrogen. The carbon will likely exist in the form of graphene, so it will be relatively easy for these organisms to make hydrorcarbons with several connected aromatic carbon hexagons, such as anthracene, and derivatives, such as anthraquinone and alizarin. Many of these polycyclic aromatic hydrocarbons can be used as dyes, meaning that they can absorb visible light, and/or are fluorescent, meaning that they can absorb ultraviolet light. Therefore, once the organisms have more access to sunlight, they may very well start photosynthesis. If we want this to happen more quickly, we can have the ocean currents carry the carbon and organisms to shallower water. This wasn't what we were planning, but life always finds a way to surprise us.

[Schiaparelliorbust]

The heat from the hydrothermal vents would likely turn some of it into carbon monoxide. The rest would likely settle on the seafloor, coating it a glistening back. It's possible that some of it would likely start to react with elemental hydrogen, producing methane. It's possible that one species will start taking advantage of that reaction as an energy source. However, the carbon will likely predominantly accumulate downcurrent and fairly far from the hydrothermal vents (or else the heat would cause it to react with the carbon dioxide), so those organisms would not be able to rely on hydrogen from the hydrothermal vents or the organisms near them. While there would be some carbon monoxide dissolved in the water, its levels would likely be lower farther away from the hydrothermal vents, so the organisms might face some pressure to develop another way to produce elemental hydrogen.

You want them to make methane from carbon. Should they use oxygen to burn it?

The carbon will likely exist in the form of graphene, so it will be relatively easy for these organisms to make hydrorcarbons with several connected aromatic carbon hexagons, such as anthracene, and derivatives, such as anthraquinone and alizarin. Many of these polycyclic aromatic hydrocarbons can be used as dyes, meaning that they can absorb visible light, and/or are fluorescent, meaning that they can absorb ultraviolet light. Therefore, once the organisms have more access to sunlight, they may very well start photosynthesis. If we want this to happen more quickly, we can have the ocean currents carry the carbon and organisms to shallower water. This wasn't what we were planning, but life always finds a way to surprise us.

Alizarin is red, so one of the dominant groups might be that color. Also, anthracene glows blue under UV light. One minor thing, chlorophyll (and other related compounds) are pigments, meaning they don't bond to their substrate, while dyes do. Do you think this would be important?

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You want them to make methane from carbon. Should they use oxygen to burn it?

Some organism will probably figure that out eventually, but it won't happen right away because they haven't evolved that yet.

Alizarin is red, so one of the dominant groups might be that color.

Like I said before, it's possible to modify the compounds to make them absorb light in different spectra.

One minor thing, chlorophyll (and other related compounds) are pigments, meaning they don't bond to their substrate, while dyes do. Do you think this would be important?

This isn't important because either way, the molecules will have to be bonded individually.

[Schiaparelliorbust]

Some organism will probably figure that out eventually, but it won't happen right away because they haven't evolved that yet.

They could use CO+H₂O→CO₂+H₂ to make hydrogen, though there wouldn't be as much CO downstream. Should we add 2H₂+C→CH₄ to the reaction list?

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There wouldn't be as much CO downstream.

Yes, that's why I thought that they could evolve photosynthesis.

Should we add 2H₂+C→CH₄ to the reaction list?

Yes.
Also, we should decide how early this happens and what other developments have happened by then.

[Schiaparelliorbust]

Also, we should decide how early this happens and what other developments have happened by then.

We can start a timeline if you'd like. I'll see if there are any online tools to make one.

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We can start a timeline if you'd like. I'll see if there are any online tools to make one.

Yes, I think that that would be a good idea.
Also, what is your progress with the ocean currents and tectonics? I think that the ocean current should carry the graphite and organisms from the hydrothermal vent to shallower water so that the organisms can start evolving photosynthesis sooner.

[Schiaparelliorbust]

Yes, I think that that would be a good idea

I found this: https://www.tiki-toki.com/

Also, what is your progress with the ocean currents and tectonics? I think that the ocean current should carry the graphite and organisms from the hydrothermal vent to shallower water so that the organisms can start evolving photosynthesis sooner.

Yes, that's a good idea. This will also allow life to be closer to land when it gets more complex.

[MathAndCode]

I found this: https://www.tiki-toki.com/

Which site we use—or even whether or not we use a timeline site—doesn't matter. We can just type it on the thread. Here's an example:
200 million years after the planet's formation: Life forms around hydrothermal vents and uses the reaction CO+H₂O→CO₂+H₂.
203 million years after the planet's formation: Life develops the reaction CO+H₂→H₂O+C.
204 million years after the planet's formation: Life develops the reaction CO₂+2H₂→2H₂O+C.
207 million years after the planet's formation: Some organisms around the hydrothermal vents start to use polysulfates as a mechanism of energy storage, recharging them using the reaction ROSO₃⁻+SO₃²⁻→ROSO₃SO₃⁻+2e⁻.
207 million years after the planet's formation: Organisms start to colonize the graphite fields, likely in order to avoid competition.
208 million years after the planet's formation: Some of the organisms near the hydrothermal vents adopt CH₃NO+HNCO→N₂+CO₂+CH₄ as a source of energy.
208 million years after the planet's formation: Organisms in the graphite fields evolve use the graphite as an energy source via 2H₂+C→CH₄. They use polycyclic aromatic hydrocarbons as reaction intermediates.
209 million years after the planet's formation: Polysulfate-building organisms develop an electron transport chain, which they use for the reaction SO₄²⁻+10H⁺+8e⁻→H₂S+4H₂O, using the energy to attach other free sulfate to sulfate chains.
209 million years ago: The reaction 2H₂+C→CH₄ is independently developed by some organisms near the hydrothermal vents.
209 million years after the planet's formation: Organisms performing CH₃NO+HNCO→N₂+CO₂+CH₄ start to colonize the area upcurrent of the hydrothermal vents.
209 million years after the planet's formation: Methane-making organisms in the graphite fields learn to use polycyclic aromatic hydrocarbons and derivatives to produce elemental hydrogen via the reaction H₂O+hv→H₂+½O₂. They haven't evolved oxygen resistance yet, so they quickly expel the oxygen, which will start to accumulate in the atmosphere, although not very quickly because photosynthetic organisms aren't widespread yet. Also, the organisms near the hydrothermal vents won't be affected much by the oxygen immediately because it is only being produced gradually so far, it readily reacts with other components of the atmosphere, and because there won't be much atmospheric gas dissolved in the water around the hydrothermal vents because they are deep underwater, and the high temperature and pressure will reduce water's ability to dissolve gases.
210 million years after the planet's formation: Organisms at the graphite fields evolve to immediately use the oxygen created to oxidize hydrocarbons as a mechanism of oxygen resistance. Some oxygen still escapes into the atmosphere, but the rate is reduced. Some oxygen reacts with the graphite, producing carbon monoxide and carbon dioxide. The carbon dioxide reacts with water to produce carbonic acid, which causes localized acidification of the ocean.
211 million years after the planet's formation: Polysulfate-building organisms take advantage of the increasing amount of methane by getting energy from the net reaction H₂SO₄+CH₄→CO₂+2H₂O+H₂S.
211 million years after the planet's formation: Graphite field colonists evolve to harness the energy released by the reactions that they use to destroy the oxygen that they create.
211 million years after the planet's formation: Some of the organsims in the shallowest part of the graphite field evolve to synthesize ammonia, both for energy and in order to cancel out the acidity of carbonic acid.
212 million years after the planet's formation: Graphite field colonists start to use photosynthesis to synthesize carbohydrates directly using water and carbon monoxide.
What do you think so far? Is this a good and realistic pace?

[Schiaparelliorbust]

Which site we use—or even whether or not we use a timeline site—doesn't matter. We can just type it on the thread. Here's an example:
200 million years after the planet's formation: Life forms around hydrothermal vents and uses the reaction CO+H₂O→CO₂+H₂.
203 million years after the planet's formation: Life develops the reaction CO+H₂→H₂O+C.
204 million years after the planet's formation: Life develops the reaction CO₂+2H₂→2H₂O+C.
207 million years after the planet's formation: Some organisms around the hydrothermal vents start to use polysulfates as a mechanism of energy storage, recharging them using the reaction ROSO₃⁻+SO₃²⁻→ROSO₃SO₃⁻+2e⁻.
207 million years after the planet's formation: Organisms start to colonize the graphite fields, likely in order to avoid competition.
208 million years after the planet's formation: Some of the organisms near the hydrothermal vents adopt CH₃NO+HNCO→N₂+CO₂+CH₄ as a source of energy.
208 million years after the planet's formation: Organisms in the graphite fields evolve use the graphite as an energy source via 2H₂+C→CH₄. They use polycyclic aromatic hydrocarbons as reaction intermediates.
209 million years after the planet's formation: Polysulfate-building organisms develop an electron transport chain, which they use for the reaction SO₄²⁻+10H⁺+8e⁻→H₂S+4H₂O, using the energy to attach other free sulfate to sulfate chains.
209 million years ago: The reaction 2H₂+C→CH₄ is independently developed by some organisms near the hydrothermal vents.
209 million years after the planet's formation: Organisms performing CH₃NO+HNCO→N₂+CO₂+CH₄ start to colonize the area upcurrent of the hydrothermal vents.
209 million years after the planet's formation: Methane-making organisms in the graphite fields learn to use polycyclic aromatic hydrocarbons and derivatives to produce elemental hydrogen via the reaction H₂O+hv→H₂+½O₂. They haven't evolved oxygen resistance yet, so they quickly expel the oxygen, which will start to accumulate in the atmosphere, although not very quickly because photosynthetic organisms aren't widespread yet. Also, the organisms near the hydrothermal vents won't be affected much by the oxygen immediately because it is only being produced gradually so far, it readily reacts with other components of the atmosphere, and because there won't be much atmospheric gas dissolved in the water around the hydrothermal vents because they are deep underwater, and the high temperature and pressure will reduce water's ability to dissolve gases.
210 million years after the planet's formation: Organisms at the graphite fields evolve to immediately use the oxygen created to oxidize hydrocarbons as a mechanism of oxygen resistance. Some oxygen still escapes into the atmosphere, but the rate is reduced. Some oxygen reacts with the graphite, producing carbon monoxide and carbon dioxide. The carbon dioxide reacts with water to produce carbonic acid, which causes localized acidification of the ocean.
211 million years after the planet's formation: Polysulfate-building organisms take advantage of the increasing amount of methane by getting energy from the net reaction H₂SO₄+CH₄→CO₂+2H₂O+H₂S.
211 million years after the planet's formation: Graphite field colonists evolve to harness the energy released by the reactions that they use to destroy the oxygen that they create.
211 million years after the planet's formation: Some of the organsims in the shallowest part of the graphite field evolve to synthesize ammonia, both for energy and in order to cancel out the acidity of carbonic acid.
212 million years after the planet's formation: Graphite field colonists start to use photosynthesis to synthesize carbohydrates directly using water and carbon monoxide.
What do you think so far? Is this a good and realistic pace?

I like the sequence of events. The evolution might be a bit fast, but given the open ecological niches and them able to produce asexually it is probably okay. We also might want to move forward the origin of life around 1000 million years in the future because the earliest undisputed evidence of life on Earth is from 3.5 Gya and the Earth formed 4.5 Gya. I will try and make a timeline tomorrow. Thanks!

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I like the sequence of events. The evolution might be a bit fast, but given the open ecological niches and them able to produce asexually it is probably okay. We also might want to move forward the origin of life around 1000 million years in the future because the earliest undisputed evidence of life on Earth is from 3.5 Gya and the Earth formed 4.5 Gya. I will try and make a timeline tomorrow. Thanks!

You're welcome. If I recall correctly, life on Earth developed fairly quickly once it started for a while, had a long period of nothing much happening, then started advancing again relatively recently. Also, you're free to move the time of biogenesis to later in the planet's history.

[Schiaparelliorbust]

You're welcome. If I recall correctly, life on Earth developed fairly quickly once it started for a while, had a long period of nothing much happening, then started advancing again relatively recently. Also, you're free to move the time of biogenesis to later in the planet's history.

Yeah, up until the Avalon explosion that led to the Ediacaran biota there wasn't much change. There were only simpler multicellular organisms like cnidarians and sponges and unicellular ones.
Edit: The timeline is asking for a start and end date in the form of DD/MM/YYYY. What should I do?