Can the theory of evolution be applied to non-living things?

To a large extent this is going to rely very much on how you choose to define both 'living things' and 'evolution'.As far as I can tell all you really need for evolution is something capable of imperfect self-replication and perhaps some selective factor. If you think of evolution strictly as a change in allele frequencies in a population then obviously only things posessing alleles are suitable, so perhaps a definition of an allele would be important as well.I would certainly agree with parasomnium that you can get very sophisticated evolutionary programs on computers nowadays and there are a lot of interesting papers looking at evolutionary systems in Tierra and Avida. I suppose the question is whether you would consider the code organisms in these programs to be actually evolving or merely undergoing a simulation of evolution, is there a difference?There are other grey areas such as viruses which are on the debatable border between life and non-life but which clearly evolve and are at least clearly in posession of alleles.Outside of those sort of things I think it all gets highly speculative. Lee Smolin proposed that if black holes gave rise to other 'universes' then a form of natural selection might operate to select for universes giving rise to more and more black holes. This idea relies on a whole stack of pretty hefty assumptions however such as that the physical 'constants' of the mother universe determine in some way those of its 'children' to allow for a heritable element.What are your views on 'living' and 'evolution'? That might help to frame the discussion a bit more clearly.TTFN,WK

But if the thing undergoing the simulation of evolution is a simulated living thing, in terms of imperfect reproduction etc.. Then are you showing that non-living things can evolve or simply that simulated living things can undergo simulated evolution?TTFN,WK

Presumably however that relies on your evolutionary algorithm being exactly identical to the rules, whatever they are, governing evolution in the real world. Otherwise surely all you have is an algorithm which approximates how we think evolution works in the real world.One could develop evolutionary algorithms with weightings which would run along distinctly different lines to what we observe in real life.Are the products of these algorithms truly evolved or merely iteratively processed? Is there, indeed, a difference?Perhaps if you told me how you personally define both living things and evolution it would help. Indeed the difference between simulated evolution and evolution and simulated living organisms and actual living organisms is surely the same one you were dismissing as merely semantic previously. Perhaps what the code is actually simulating is a genome, could you have a real organism with a simulated genome?We can't really deal in specifics until we all have a shared view of what we are talking about.TTFN,WK

If you had bothered to define it in those terms yourself when I asked you to then this discussion would have been much simpler. Neds definition is by no means one that you are likely to turn up. In fact it seems almost specifically tailored to be as broad as possible in what it allows to evolve, which is obviously going to leave much more scope for non-living things.You could just as easily produce a similarly broad definition of life which would allow all imperfect self-replicators in. Your point that the code organisms don't produce exrement is irrelevant to the point. Unless your specific definition of life relies on the ability to excrete waste matter.Perhaps you will finally allow that actually defining the terms of what you are discussing is important for having a meaningful discussion?It would also help if you would focus more on the published work on artificial life evolution, such as the work using tierra and avida, rather than your own travelling salesman solution, since everyone can have proper information and access to data on published works whereas all I have is what you have said in passing in this thread as to your own program.TTFN,WK

Yes, you told me this. You have yet to give any reason why I ought to believe this however. You appear to be relying on an acceptance of your claim that you have produced an evolutionary algorithm which produces an optimal solution, I assume your quick solution is optimal rather than simply some solution, to a non-P problem. Has this been demonstrated on some other thread or are you simply relying on us accepting your authoritative statement on the matter? Can you show this in some way? What are the differences? Without an actual definition of what life is how can you conclude that your code 'organism' is not fulfilling the neccessary criteria?TTFN,WK

Dear Parasomnium,I'm glad you are not claiming your solution is optimal, I thought I was going to have to put you in the bin for cranks making grandiose claims. As it is you haven't really done anything to make this issue clearer. The fact that you can generate some sub-optimal solution for the TSP using an evolutionary algorithm is still just an assertion, although not one I have any trouble believing. Just out of interest how many 'generations' did it take to 'evolve' your 99% good solution?Why do you think something you yourself did, the details of which are known only to yourself, is a better basis for a discussion than research everyone can have equal access to? If you expect me to familiarise myself with classifications of P and NP problemks and the equivalency of NP optimal solutions why is it too much to expect you to familiarise yourself with the published research on digital evolution? This research should surely provide just as adequate a basis for this discussion as your own work? Your first point seems vague and probably redundant. What is your TSP solution other than what it is? What behaviour does it regulate? Similarly a sequence of RNA may evolve in and of itself. I understand how this relates to evolution but I think saying 'outward appearance' and 'behaviour' are misleading and give too much of an organismal slant when, after all, you could be talking about an improved binding affinity in some protein. I think 'some observable change' would be sufficient. Arguably the 'evolution' of a limb is only really the evolution of sequences of DNA such that the final form of the limb is altered, I don't think you can seperate these two levels out as you appear to be trying to do, perhaps if you showed how these levels equate to aspects of digital evolution your reasoning might be clearer. Your other two points simply seem to be random mutation and natural selection, which I have no argument with. Demonstrate this, show how the itineraries, or better still of the code 'genomes' of digital organisms in Tierra or Avida, cannot qualify as living by any 'meaningful' definition but can still undergo the neccessary processes to qualify as 'evolving' using your criteria. Presumably at some point in this process you will finally have to actually give what you consider a 'meaningful' definition of life and we can begin to properly discuss this. At the moment this is simply a further bald reassertion of your claim.TTFN,WKThis message has been edited by Wounded King, 05-17-2004 04:58 AM