Or would it be appropriate to consider that different life could be compared to fires in the sense that there are different chemical interactions that produce the same result?
An extension of this question that I find much more interesting: Given that life is a chemical reaction, do you think that the first life on earth was a single instance/single reaction, or multiple reactions/instances of which were perhaps chemically the same so coexisted, but one survived?
My knowledge of chirality is limited but from what I understand the same chirality of every life form would indicate that we came from the same original chemical structure — but wouldn’t that indicate the possibility of other instances of the same basic origin of life, but different than what we originated from? Maybe ours was the one that could sustain itself due to our composition, or would other life be able to life with different chirality?
The brings the question, how long did the first life form exist and how long did it take for it to reproduce? If other instances are possible, and if there were, I wonder if maybe only we were able to reproduce…so that brings yet another question — is reproduction even a fundamental characteristic of life? (Probably a very bad analogy) but there are sterile life by defect so maybe if there were multiple instances they started off with different traits and chemical composition isn’t so rigid. Maybe we were just lucky enough with our specific composition to be able to be sustained.
Obviously this is all [amateur] speculation and nobody knows, but I am wondering what other people think and if people more knowledgeable on the subject think there is any foundation to this speculation.
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I think it depends on makup. I suspect physics works the same in all of the universe.
Earthly life forms are all chemically distinct, and each life is more than just a single chemical process. Alien life forms would presumably be more different from us than other terrestrial life forms are.
I’m dropping this here for the group.
https://youtu.be/TK1E3heBSiI?si=Pn7Rl7bXSVZ7jpOa
>If life is a chemical reaction, would foreign life be chemically the same as life as we know it?
Probably not, but there’s really no way to be sure without experimental evidence. It’s worth noting that of course not all life on earth is exactly the same chemically, but it is fundamentally the same on a basic level.
>Given that life is a chemical reaction, do you think that the first life on earth was a single instance/single reaction, or multiple reactions/instances of which were perhaps chemically the same so coexisted, but one survived?
Well, life is a lot of chemical reactions happening all together at the same time. The earliest life that was proper "life" would probably have involved multiple different bits of chemistry working together.
We don’t know what was going on in the early days of life, but we can be pretty confident that all living life shares a single starting point. There’s no way that, for example, (almost) all the amino-acid codons for proteins would be the same otherwise, or that all life would use ribosomes.
>My knowledge of chirality is limited but from what I understand the same chirality of every life form would indicate that we came from the same original chemical structure — but wouldn’t that indicate the possibility of other instances of the same basic origin of life, but different than what we originated from? Maybe ours was the one that could sustain itself due to our composition, or would other life be able to life with different chirality?
Possibly there was some other early life or protolife that used different chiral molecules. There’s really no way to know at this point. It doesn’t seem intrinsically impossible…but on the other hand, we don’t know for sure if some factor was pushing life to use the chirality we use.
>The brings the question, how long did the first life form exist and how long did it take for it to reproduce? If other instances are possible, and if there were, I wonder if maybe only we were able to reproduce…so that brings yet another question — is reproduction even a fundamental characteristic of life?
Oddly, reproduction probably has to come before life, in the same sense that RNA molecules can catalyze their own replication and lipid bubbles can split and reproduce, etc. You can’t really get to the point of life proper without the sort of refining that comes from replication (and particularly, replication in a way where daughter products retain some characteristics of the parent).
Which is a really important point that needs to be highlighted…the reason life and replication are so tightly tied together is that without replication you don’t get iterative improvement and increases in complexity.
For the most part life as we know it uses the best and mostly widely available options already with one possible exception. Carbon is by far the best candidate for building biology with, with only silicon being a distant second, and water is almost the only biologically useful solvent period.
Life thats built in other ways is not impossible but the expectation should be for life to emerge in the easy situations much more often than the much less likely situations.
In regards to the likelihood that foreign life would be have similar chemistry to us, id say that it is fairly likely. In order to have complex molecules like the amino acids in us, you need an element that can produce chains while still allowing for different functional groups. Of the elements on the periodic table only two have sufficient sp3 hybridized character and stability to form such bonds. Those two elements are carbon and silicon. Silicon bonds however are less stable than those of carbon. Silicon is also less common as a form that could be biologically active on earth. Most of it is locked up in sand as silicon dioxide.