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Originally Posted by Martian
Abiogenesis has more to do with astrobiology than evolutionary theory. We have direct observable evidence that life spontaneously came into existence on our planet; the question of how is interesting and not well understood yet, but evolutionary theory deals more with what comes after. Evolution is strictly an answer to how complex life can develop from simpler organisms through the principle of natural selection.
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Technically, the standard Theory of Evolution has more tools in it's box than Natural Selection.
You can demonstrate mathematically that features that are not selected for or against (ie, are neutrally selected) can be created or removed from a population over time. The same applies to features that are weakly selected for/against.
If you have two separate populations undergoing identical selection pressure, but kept separate, one should some features of the two populations to diverge. This could cause specification without any distinctive selective pressure on the two populations.
And given a low selective pressure, this kind of thing could even happen without division. Imagine a mutation that led to sexual arousal only from seeing blue eyes: with low enough selective pressure, this mutation (which could even be mildly mal adaptive!) could split a population into two sub-species.
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Interestingly, this creates one of those little nooks in our understanding that allow theology and modern science to co-exist peacefully. We know that life originated, and we know (more or less) what happened after that. As to what happened before, what you want to believe is your lookout. If you want to believe that God nudged a couple of amino acids in the right direction, more power to you.
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Note that work into pre-"life" evolution of amino acids is proceeding apace. Environments that produce self-assembly of random long amino acid chains on one end, and created shorter, "damaged" enzymes based off of our current ones and finding situations in which they function reasonably well on the other.
If you can find a short enough amino acid chain that duplicates itself, and is somewhat robust to variation, and then demonstrate that random assembly of amino acids in a pre-life environment is likely to produce such a chain, you have a step along the "formation of life" ladder candidate.
Ie: it might be possible to show that molecular life is mathematically expected, given the early earth environment. And then it might be possible to show that more complex life arising from it is expected. Etc etc. This would push back the requirement for divine intervention one step: to creating the environment in which life is expected to take hold.
Note that evolution is, in a sense, a mathematical property of certain types of systems. So you can talk about evolution when talking about things that aren't lifeforms.
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Admittedly, this is a somewhat weak argument from a scientific standpoint due to the difficulty of obtaining proof, but it does explain why attempts to replicate spontaneous abiogenesis in the lab have so far failed.
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Well, they haven't produced full-fledged cells from the basic building blocks of life. But that isn't expected to happen: the cells of even primitive life forms seem to be the result of many evolutionary steps. And each of those steps might have taken millions of years to pull off in the wild...
So what one has to do to "replicate" it in the lab is guess what each step is, and then work out method of getting from one step to the next.
Lots of work has been done on this subject, some of it very promising.