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MathAndCode wrote: January 25th, 2021, 6:28 pm I think that the video that you sent me said that plants don't use green light because their ancestors evolved in a world where the green light was already taken up by organisms closer to the surface. The early life here would probably have a variety of colors.

Was it this video? I've sent you several. If yes, it's been a while since I watched it. Also, I found all of these photosynthetic pigments on Wikipedia:
Carotene: an orange pigment
Xanthophyll: a yellow pigment
Phaeophytin a: a gray-brown pigment
Phaeophytin b: a yellow-brown pigment
Chlorophyll a: a blue-green pigment
Chlorophyll b: a yellow-green pigment

Schiaparelliorbust wrote: January 25th, 2021, 6:36 pmWas it this video?

Yes, that's it.

Schiaparelliorbust wrote: January 25th, 2021, 6:36 pmAlso, I found all of these photosynthetic pigments on Wikipedia:

Keep in mind that the absorption spectra for each can be shifted somewhat by changing the functional groups.

MathAndCode wrote: January 25th, 2021, 6:47 pm Keep in mind that the absorption spectra for each can be shifted somewhat by changing the functional groups.

So you can just ''adjust'' them? Do you think we should get our molecules like that?

Schiaparelliorbust wrote: January 25th, 2021, 6:55 pmSo you can just ''adjust'' them? Do you think we should get our molecules like that?

Yes, that seems more likely to evolve than a completely new photosynthetic molecule.

MathAndCode wrote: January 25th, 2021, 6:59 pm Yes, that seems more likely to evolve than a completely new photosynthetic molecule.retinal

Can you please do the tweaking? I don't know how to do it. Do you think purple is good? AFAIR from the video, the purple bacteria used retinal and it seems to have a relatively simple structure.

Schiaparelliorbust wrote: January 25th, 2021, 7:06 pmCan you please do the tweaking? I don't know how to do it.

I don't think that we have to specify the exact changes.

Schiaparelliorbust wrote: January 25th, 2021, 7:06 pmDo you think purple is good? AFAIR from the video, the purple bacteria used retinal and it seems to have a relatively simple structure.

It's more about the structure and less about the color. Retinal is related to carotenes, which are orange.

MathAndCode wrote: January 25th, 2021, 7:09 pm I don't think that we have to specify the exact changes.

Good.

MathAndCode wrote: January 25th, 2021, 7:09 pm It's more about the structure and less about the color. Retinal is related to carotenes, which are orange.

Oh, ok. If we changed them would they still likely be orange?

Schiaparelliorbust wrote: January 25th, 2021, 7:14 pmOh, ok. If we changed them would they still likely be orange?

No, their absorption frequencies would likely shift.

MathAndCode wrote: January 25th, 2021, 7:15 pm No, their absorption frequencies would likely shift.

Would they shift arbitrarily? I mean purple (retinal) is very far away from orange (carotenes).

Schiaparelliorbust wrote: January 26th, 2021, 7:04 amWould they shift arbitrarily? I mean purple (retinal) is very far away from orange (carotenes).

I think that there are some rules concerning which direction, but I don't think that it's necessary to worry about the specifics.

MathAndCode wrote: January 26th, 2021, 10:58 am I think that there are some rules concerning which direction, but I don't think that it's necessary to worry about the specifics.

Then do you have any preference for the color?

Schiaparelliorbust wrote: January 26th, 2021, 11:25 amThen do you have any preference for the color?

I think that organisms will likely use multiple colors in order to be able to get more energy.

MathAndCode wrote: January 26th, 2021, 11:27 am I think that organisms will likely use multiple colors in order to be able to get more energy.

Then let's choose a few colors. I think there should be red and green at least.

Schiaparelliorbust wrote: January 26th, 2021, 11:30 amThen let's choose a few colors. I think there should be red and green at least.

There will probably also be something between orange and yellow and something between blue and violet.
Also, be aware that some compounds may have multiple absorption peaks. Chlorophyll is one example.

MathAndCode wrote: January 26th, 2021, 11:46 am There will probably also be something between orange and yellow and something between blue and violet.
Also, be aware that some compounds may have multiple absorption peaks. Chlorophyll is one example.

Yes. Then can we have perhaps four pigments? They could be red, orange-yellow, green, and blue-violet. A single organism can use two different pigments, like red algae, which uses both chlorophyll and phycoerythrin, which is red.

Schiaparelliorbust wrote: January 26th, 2021, 12:01 pmYes. Then can we have perhaps four pigments? They could be red, orange-yellow, green, and blue-violet. A single organism can use two different pigments, like red algae, which uses both chlorophyll and phycoerythrin, which is red.

Yes, and through methods before, it could probably adjust the frequencies somewhat through various modifications.

MathAndCode wrote: January 26th, 2021, 12:04 pm Yes, and through methods before, it could probably adjust the frequencies somewhat through various modifications.

Because our planet is in the Lagrange point, the third of the planet facing the suns will get more sunlight. We could have photosynthesizers with pigments more tolerant to radiation there, and less tolerant ones in the two sixths around receiving less sunlight.

Schiaparelliorbust wrote: January 26th, 2021, 12:08 pmBecause our planet is in the Lagrange point, the third of the planet facing the suns will get more sunlight. We could have photosynthesizers with pigments more tolerant to radiation there, and less tolerant ones in the two sixths around receiving less sunlight.

I thought that we agreed to go back to a P-type system. Also, the planet definitely shouldn't be tidally locked.

MathAndCode wrote: January 26th, 2021, 12:11 pm I thought that we agreed to go back to a P-type system. Also, the planet definitely shouldn't be tidally locked.

Oh ok sorry. How far is the planet now? Also, the stuff I said still applies to latitude differences.

Schiaparelliorbust wrote: January 26th, 2021, 12:14 pmOh ok sorry. How far is the planet now? Also, the stuff I said still applies to latitude differences.

The habitable zone is still at the same distance. Should I type it again?

MathAndCode wrote: January 26th, 2021, 12:26 pm The habitable zone is still at the same distance. Should I type it again?

Yes please. I think at most one or two groups of photosynthesizers should be the dominant group too.

Schiaparelliorbust wrote: January 26th, 2021, 12:29 pmYes please.

The distance is 1.2 AU.

Schiaparelliorbust wrote: January 26th, 2021, 12:29 pmI think at most one or two groups of photosynthesizers should be the dominant group too.

That's the most likely situation. However, the other groups will likely continue to persist.

MathAndCode wrote: January 26th, 2021, 12:42 pm That's the most likely situation. However, the other groups will likely continue to persist.

Yes, I was never advocating the eradication of the other groups. So now that we have photosynthesizers, let's determine which groups become dominant and create single or pluricellular (not multicellular, more like an algae mat) groups that eat them.

Schiaparelliorbust wrote: January 26th, 2021, 12:50 pmYes, I was never advocating the eradication of the other groups. So now that we have photosynthesizers, let's determine which groups become dominant and create single or pluricellular (not multicellular, more like an algae mat) groups that eat them.

Actually, we should decide the reactions first, as the planet could undergo an analog of the Oxygen Catastrophe that could change the hierarchy.

MathAndCode wrote: January 26th, 2021, 12:58 pm Actually, we should decide the reactions first, as the planet could undergo an analog of the Oxygen Catastrophe that could change the hierarchy.

Do you mean the photosynthetic reactions?