Let's create an alien biosphere!

[Schiaparelliorbust]

We should figure out whether or not they can develop photosynthesis.

I had said earlier that I don't think they need photosynthesis, but if you disagree please say so.

[MathAndCode]

I had said earlier that I don't think they need photosynthesis, but if you disagree please say so.

I guess that we'll assume that they can't develop it.

[Schiaparelliorbust]

I guess that we'll assume that they can't develop it.

Yes, that's good. If I'm not mistaken, most if not all accessible compounds are used by one life form or another now.

[MathAndCode]

Yes, that's good. If I'm not mistaken, most if not all accessible compounds are used by one life form or another now.

I suspect that the increase in biodiversity will lead to more reactions being used. Shall we figure out some new reactions?

[Schiaparelliorbust]

I suspect that the increase in biodiversity will lead to more reactions being used. Shall we figure out some new reactions?

I think we should first figure out what sort of reactions (attacking, defending, energy, movement) might be beneficial to these organisms.

[MathAndCode]

I think we should first figure out what sort of reactions (attacking, defending, energy, movement) might be beneficial to these organisms.

Okay. We've already covered predation and defense, right?

[Schiaparelliorbust]

Okay. We've already covered predation and defense, right?

Yes. I think movement is lacking in most of these organisms. To move quickly you need to use up a lot of energy in a short period of time. How might they accomplish that?

[MathAndCode]

Yes. I think movement is lacking in most of these organisms. To move quickly you need to use up a lot of energy in a short period of time. How might they accomplish that?

One type of organism has an electron transport chain. Perhaps this will make it successful, causing it to undergo adaptive radiation.

[Schiaparelliorbust]

One type of organism has an electron transport chain. Perhaps this will make it successful, causing it to undergo adaptive radiation.

That sounds good. What do you suggest? I think that the graphite beds are ripe for the taking.

[MathAndCode]

That sounds good. What do you suggest? I think that the graphite beds are ripe for the taking.

It probably will go out to them eventually, but let's track what happens at the hydrothermal vents first, as they are now in shallow water, which allows the photosynthesizers from the graphite beds to colonize them—if they can make polycyclic aromatic hydrocarbons when graphite isn't in as abundant supply.

[Schiaparelliorbust]

It probably will go out to them eventually, but let's track what happens at the hydrothermal vents first, as they are now in shallow water, which allows the photosynthesizers from the graphite beds to colonize them—if they can make polycyclic aromatic hydrocarbons when graphite isn't in as abundant supply.

Do they absolutely need a carbon ring for photosynthesis?

[MathAndCode]

Do they absolutely need a carbon ring for photosynthesis?

No, but they need some kind of conjugated hydrocarbon.

[Schiaparelliorbust]

No, but they need some kind of conjugated hydrocarbon.

What do you suggest then?

[MathAndCode]

What do you suggest then?

How much will reduced compounds have depleted?

[Schiaparelliorbust]

How much will reduced compounds have depleted?

You're asking how much depleted compounds have depleted, right? If yes, then I haven't thought much about it. I mean anything that might oxidise will have depleted. I'll think about it some more. I can't browse this topic too easily now because I'm on mobile right now. I will be in front of my computer soon.

[MathAndCode]

You're asking how much depleted compounds have depleted, right? If yes, then I haven't thought much about it. I mean anything that might oxidise will have depleted. I'll think about it some more. I can't browse this topic too easily now because I'm on mobile right now. I will be in front of my computer soon.

Didn't we agree that it would take at least six hundred million years for everything to be depleted?

[Schiaparelliorbust]

Didn't we agree that it would take at least six hundred million years for everything to be depleted?

Thanks for reminding me of that. I think depletion would happen much faster though. There only needs to be a relatively low amount of oxygen to "cancel out" the combustible substances in the atmosphere.

[MathAndCode]

Thanks for reminding me of that. I think depletion would happen much faster though. There only needs to be a relatively low amount of oxygen to "cancel out" the combustible substances in the atmosphere.

I think that it took about 620 million years for Earth, and our planet has a more massive atmosphere.

[Schiaparelliorbust]

I think that it took about 620 million years for Earth, and our planet has a more massive atmosphere.

What was depleted on Earth? Was it CO?

[MathAndCode]

What was depleted on Earth? Was it CO?

I think that it was mostly methane and ammonia.

[Schiaparelliorbust]

I think that it was mostly methane and ammonia.

I can't find anything on prehistoric concentrations of either of those, so I'll go ahead and trust you here.

How much will reduced compounds have depleted?

Then I don't know anything really.

[MathAndCode]

Then I don't know anything really.

Do you know how long after the oxidation started this will be?

[Schiaparelliorbust]

Do you know how long after the oxidation started this will be?

What will be? I don't think you mean how long it will take for them to be nearly completely depleted.

[MathAndCode]

What will be? I don't think you mean how long it will take for them to be nearly completely depleted.

I mean the time that we are discussing now, when movement becomes prevalent.

[Schiaparelliorbust]

I mean the time that we are discussing now, when movement becomes prevalent.

Oh, ok. Probably once the oxygen becomes at least a few percent. One thing I didn't think of is that these mobile microbes will probably live close to the surface to benefit from the oxygen.