I have been thinking a little about the origins of life, and was further inspired by this question: How did the first self replicating organism come into existence?
I can accept that we don't quite know exactly how, but has any large-scale/long-term simulation been carried out?
There have been experiments but they seem to have been on a small scale. As an example, according to the Abiogenesis page on Wikipedia, some experiment which spontaneously formed peptide structures was carried out by Sidney Fox during the 50s and 60s.
What would be really interesting is if there had been some experiments or simulations carried out during a very long time, plausibly allowing for extremely low-probability structures to form. I doesn't matter whether this simulation/experiment has been carried out in a lab or as a computer simulation. There is of course the interesting but old "Conway's Game of Life" simulation, but according to my search efforts nobody has really tested it on a very large scale and in 3D.
Again, I'm looking for something extensive, like a decades-long single lab experiment or a simulation that has been run for years.
Answer
What you are possibly thinking of is large versions of the Miller Urey Experiment where a mixture of reducing gasses carbon dioxide, ammonia, nitrogen and the like are subjected to electrical arcs in a closed flask reaction, resulting in some biological molecules being produced.
Opinions have changed - Miller Urey did get the atmosphere wrong and so their finding of amino acids is not necessarily, but variations of this experiment continue to be done, with different conditions in the reaction vessel which reflect typical or even unusual conditions. I've found some nice collections and reviews. There continues to be an enthusiastic effort even today.
Looking over several of these overviews, it's clear that many different conditions are being tried - reactions on mineral surfaces, examining chemicals on meteorites, near volcanic vents, different kinds of radiation. What I don't see is anyone going to a huge tank.
I think that this might not have been tried (perhaps someone else will find a counter example), but if it were not me, I would probably not try longer experiments either.
There's some good reasons for this, if true.
Firstly all the published descendants of the Miller experiment have produced biologically relevant compounds after a few days. Extending the experiment a few orders of magnitude may not prove anything new.
Secondly, the longer a reaction is run the more likely the sealed containers and heaters and other apparatus has to fail, causing you to restart or include contaminants that would ruin it.
Thirdly, one is not going to run an experiment that will ever come close to reproducing the time spans or volumes over which life emerged on earth - that was perhaps a few hundred million years over the area of the planet.
That's not to say you won't find out something new - an extra week could produce a new set of compounds or even a replicating system - we don't know if we haven't done it, but the nature of science is that you have a little time and money for a project like this and you would like to prove feasibility - 'it could have happened this way'. By selecting the conditions and doing a series of modest experiments which allows some to fail so that you can find something new.
I would say the observation of other planets and analysis of meteorites are getting closer to your idea - they are huge systems and been going for billions of years. Titan is especially promising. They just aren't the same conditions as Earth.
In brief, nothing is both affordable and perfect in proto-biotic research.
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