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Create life

  1. Aug 7, 2010 #1
    Is it possible to create life by subjecting pure elements to the right conditions , basically can u create life out of nothing but atoms/molecules
     
  2. jcsd
  3. Aug 7, 2010 #2
    Not yet. The quintessential origins experiment is Miller-Urey:
    http://en.wikipedia.org/wiki/Miller–Urey_experiment

    They subjected ammonia, water, methane, hydrogen, to electric sparks for several days to simulate the primeval earth and produced various amino acids in low concentrations (in school I once created alanine (the simplest amino acid) from ammonia and acetic acid). But that's not yet life. Life as we know it is a self-contained, metabolizing, reproducing, evolving system. We'll get there one day for sure. It's just chemistry.
     
  4. Aug 8, 2010 #3
    Thanks read about Miller–Urey experiment interesting stuff still is amazing how molecules can form a living organism
     
  5. Aug 8, 2010 #4
    No doubt it is possible, and no doubt it is possible to do it faster than it happened on the first occasion on this planet. How many times faster? ten times faster? However, how fast was that? A million years? A hundred million? Suppose we manage to do it in ten thousand years; is that failure or success? If success, whose success? All the generations of workers who never saw the fruits of their labours?
    Then again, suppose we do not limit ourselves to the abiogenic processes that originally led to life as it exists on Earth today (or 3+ billion years ago). Suppose instead we study some cells and decide what a minimal viable cell would need, much as some research workers actually are doing today. Then suppose we put the necessary materials together and get working, reproducing cells.
    Was that creation or assembly?
    If assembly, then is it marvellous or ordinary? If marvellous, what is marvellous about it? Is it marvellous that we can manage such science and technology? Or marvellous that living creatures are so simple in their fundamental mechanisms?
    Also, what is the borderline between life and non-life? A "dead" cell? A "live" virus?
    The question is as hard to define as to answer. The implications might be harder still.
     
    Last edited: Aug 8, 2010
  6. Aug 8, 2010 #5
    I think if we manage to do it it will raise the question why would matter arrange its self to produce a life from? i think assembly is part of the process of "creation of life"
     
  7. Aug 8, 2010 #6
    We can raise the question without doing it ourselves. Personally, I don't see a problem at all with matter forming life. We could just as well ask why does matter do anything at all? For me it's a simple answer: life is possible because such configurations are persistent in our Universe give suitable conditions: energy source, raw materials, time, then life is inevitable (my opinion) in the same way that a ball dropped on earth inevitably falls to the ground.

    But we could as well ask, "why is life possible?" To answer that, I believe one must look at how the Universe is constructed. Life as we know it is biological. But it doesn't have to be in my opinion. The biology is just a convenience that life happened to use on earth. Other substrates would work equally well I suspect because life is not the trappings but rather the underlying dynamics: strip away all the chemistry and biology from life, and what remains is the pure dynamics and that dynamics exists independently of the Universe but can be instantiated in it because of how the Universe works.

    Just my opinion guys. One day we'll learn how to create a Universe. I'm sure of it, and we'll understand how the creation process imbues the instantiation with particular physical properties and particular instantiations of a Universe will imbue it with the potential of allowing dynamics we attribute to life while other instantiations will not.
     
    Last edited: Aug 8, 2010
  8. Aug 10, 2010 #7

    bobze

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    Forgive me for recycling a post (I made) on another forum. The question dealt with chirality, but I think some of the information you'll find useful;

     
  9. Aug 11, 2010 #8
    Reading the last two comments made me question can life form with out using any of the components life on earth has or can it form using other building blocks that don not derive from the elements that made life possible on earth today. basically can life form from a different combination of elements that life does not relay on as we know it
     
  10. Aug 15, 2010 #9
    So the thinking seems to be that life can be created by assembling all the right chemicals, it's just too difficult a process today. But, other than the bioengineering aspects, nothing else is needed.

    What about the following thought experiment, or perhaps it's already been tried. Take a simple living organism, say an amoeba, and "kill" it by removing one of it's essential parts, say the nucleus. Since this is a thought experiment, let's say we do this so precisely that we don't disturb any other aspect of the amoeba -- all we do is physically separate out this one critical part from the rest of the amoeba, so the amoeba can't function as a living organism, and consists only of all the chemicals needed to build an amoeba, but in two separate batches.

    Now, put the critical part back in. Will we once again have a living amoeba, or is there something still missing to make the amoeba go on to eat, split, or do whatever living amoebas do?
     
  11. Aug 15, 2010 #10

    Q_Goest

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    The alternative requires magic.
     
  12. Aug 15, 2010 #11
    It is a reasonable question, but how about just freezing the organism so cleverly that it comes to no harm, but cannot do anything "alive"? Then thawing it equally carefully? Would that not meet your needs?
    If you did it by removing and replacing critical parts, then various other parts, such as many enzymes, would go on working and probably would wreck the mechanism. It might even lead to apoptosis.

    BTW, you might find some of the earlier chapters of "The Mind's I" By Hofstadter & Dennett very revealing in this connection. As well as entertaining.

    Cheers,

    Jon
     
  13. Aug 15, 2010 #12
    Good point!

    Jon
     
  14. Aug 15, 2010 #13
    Just to clear up something: My comments above are my own personal comments about life in that I believe it can be mimicked by processes other than biochemistry but that does not mean it's true. Also, in terms of biochemistry, carbon seems ideally suited for life in that it is unlikely other elements, such as silicon, can be substituted to give rise to the diversity we see on earth. Personally, I believe naturally occurring biochemical life of any meaningful complexity, probably has to be carbon-based. However, I am optimistic that artificially synthesized systems which mimic life can be created and these may not rely on carbon.
     
  15. Aug 15, 2010 #14
    First, thanks for the Hofstadter book suggestion, he is one of my favorite authors but I've not read that particular one.

    As far as your freezing idea, it's an interesting thought, but I don't think it addresses the same hypothesis. I don't know anything about biology except for what I've read in the lay literature, but I was trying to approach the OP's question from a test of hypothesis approach.

    If the hypothesis is that life can be created from basic atoms/molecules, then the best test is to try it from inanimate matter. And, since it's impossible with today's technology to assemble all the parts, I thought of first disassembling what we know works, then try to reassemble it. But you raised a valid objection as to the difficulty of such an experiment, because the organism would be wrecked.

    As far as freezing, the problem is that the molecules might still be "communicating" physically, in the sense that electromagnetic signals might still flow between molecules. So an objection could be raised that life was not created, only resusicated from a very slow state.

    With the parts physically separate, I don't know what objection could be raised, unless one proposed some weird biological force at a distance. Granted, the fact that the organism was previously alive doesn't make for a perfectly controlled experiment, but maybe that's the best that can be done given current technology.

    As a poor analogy, consider the hypothesis that a computer is only the sum component of its parts, and can be created from scratch with the right parts. We know this is true from experience, but suppose we knew nothing about computers, they just showed up. If we could not create a computer from scratch, we could take a running computer, remove the CPU, then put it back in to see if it would restart. Putting it into a sleep mode would not be the best test, because perhaps electrical continuity is important to its functioning, even if it's in a sleep mode.

    I find this a very interesting question, and my gut tells me that even if all the chemicals were assembled in exactly the same way, life would not appear. But I'm sure I'm guided in this by my own human bias, thinking that life must have some special property aside from the chemicals. However, if you push me as to what would be missing so that life would not appear, I have no answer, so maybe Occam's razor applies and life is just a bunch of chemicals. But I sure wish a good experiment could be designed....
     
  16. Aug 15, 2010 #15

    Pythagorean

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    No "weird biological force" is neccessary. As Jon implied, your going to cause malfunctions in the cells machinery if you just disconnect it while it's running. That's like taking apart your engine while it's running; it will wreak havoc on the machine. The point is that the cell is more than just the matter, it is also the processes taking place between the matter.

    As Jon suggested, you can greatly slow down those processes by removing heat from the system.
     
  17. Aug 16, 2010 #16
    It is a real tour de force. Don't try to read it in a hurry; it strips the skin and tendons right out of your assumptions! Those two make a formidable pair for challenging one's attitudes. In that respect I have never read a book to match it.

    With some background in biochem and general biology (not claiming authority, just explaining my mental slant!) I am perhaps biased in favour of a mechanistic view of the nature of life. Everywhere I look I find mysterious processes that are limited (or empowered) by info theory, chemistry, physics, you name it. Even QED if you like! (Shades of Schroedinger!) On the farm, in the lab and the hospital we see that grafting, messing with the mechanism, changing the controls, all works in ultimately explicable ways.
    Have we explained every principle compellingly yet? Certainly not. I am not quite confident that we have completely nailed the idea of life, as opposed to mechanism, to the barn door. Certainly life is dependent on mechanism, but is it just mechanism? Watch this space! Can it be generated by "dead" mechanism? I definitely think it can; I unreservedly believe (not in the sense of doctrine, but in the sense of opinion) that if you took the right "dead" molecules and assembled them properly, you would get living creatures and I do not believe that they would lack any mysterious principle that "naturally" assembled organisms would appear to have. Certainly we do not find any sign that living creatures look any less alive when fed nutrients synthesised from the raw elements.
    That sort of thing is why I regard mystical opposition to say, genetically modified organisms, with contempt, rather than disagreement. (There certainly are problems that responsible practitioners should bear in mind, but that is another matter.)

    I do not see what is so poor about the analogy. As I see it, the differences are in the nature of the parts and the ability of the assembly to survive certain classes of procedure. I think it was Pythag. who pointed out the analogy of working on a running engine.

    As for the "sum of its parts" idea, it is to be applied with deep, deep reserve. I in my turn am deeply fascinated by the concept of what I call entity. What makes a "thing" a "thing". Strawson is famous for his book "Individuals", though I could never bring myself to read through it (I was spending too much time by half way through, trying to read things based on statements from earlier chapters that I disagreed with! There is a limit to how much pain I could bear from sustaining multiple levels of cognitive dissonance!:grumpy:) Be that as it may, I see an entity as any set or structure of one (zero? minus 1?) or more component entities that can be seen as having some sort of interdependent informational relationship. The entity is then the set of the components, plus the set of the interrelationships, plus the set of relationships with the rest of the universe. Those plusses are not non-essential, optional extras. Think of a Meccano set. The pile of parts is not the building you may have erected, and not the ship or windmill you might have made with the same parts.
    Much the same with life. There are precious few molecules in your body that differ from the corresponding molecules in the cat on your lap or the fish in your pond. Even most (though not all!) of the molecules that do differ would fit into corresponding functions in suitable parts of your body.
    You can see why my views are so mechanistic, I hope!

    The one thing I cannot make any sense of in such terms is the concept of subjective consciousness. As a computer man, I can read or even write programs that behave in particularly life-like fashions, and easily imagine programs on a much, much larger and more sophisticated scale but I also cannot see any basis for believing that the construction has a subjective awareness such as I am aware of in my own mind and not in any other thing in the world (though in my opinion probably all humans and at least many living things besides have something similar.) But my awareness goes away if I am under an anaesthetic and returns (possibly somewhat changed) if I wake up. Why should I believe that if you assembled a fully functional Frankenstein's monster to match my own construction, out of nutrient elements, it would be any less conscious? (Return to "The Mind's I". Do not pass Go. Do not collect...)

    Well, as I implied, Aristotle had it right about the whole being not simply the same as the sum of its parts. Such experiments as already point the way are very suggestive...:smile:

    Cheers,

    Jon
     
  18. Aug 16, 2010 #17
    Have there been no further experiments along the lines of creating mixtures involving the many, many more chemicals which existed back then and subjecting them to radiation, cosmic rays, radiation, sunlight, sparks, and the other sources of energy which also existed back then?

    Ah, http://en.wikipedia.org/wiki/Miller–Urey_experiment#Other_experiments".

    I'm particularly intrigued by this: "The University of Waterloo and University of Colorado conducted simulations in 2005 that indicated that the early atmosphere of Earth could have contained up to 40 percent hydrogen..." If indeed organics could have been produced in the atmosphere, that would have eliminated a large number of reducing agents to counter the newly formed life. That and the fact we've found complex, pro-life compunds in asteroids (and perhaps comets) suggests a panspermia hypothesis, but perhaps not that life itself arrose from elsewhere, but that the building blocks of live came from external sources whose conditions were ripe to build those building blocks, but not ripe to support the creation of life.

    Thus, perhaps life can only exist when two conditions are present - a life preformation source, (perhaps on a moon of Jupiter, knocked to Earth on an asteroid) and a life-assembling and supporting source (Earth itself).
     
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  19. Aug 16, 2010 #18
    I try to be scientifically agnostic on the nature of life but, as I said, have a bias against a purely mechanistic explanation. However, given the ever-increasing acceptance and demonstration of quantum physics, I'm more willing to accept a mechanistic interpretation with quantum uncertainty at the very small end, where the mysteries of life may reside.

    And I believe, also in the sense of opinion, that you would not. But I said I couldn't think of what would be missing, and after this discussion, I believe it's the process that would be missing. Even in a mechanistic universe, the initial ball has to get started. And if a full amoeba could be composed, whatever biological processes have to flow would have to be started, probably in the right sequence and in the right time for there to be a live amoeba.

    Taking this further, I'm not sure that life has ever recreated itself save for that initial time that it began. Can you think of a single life form existing today that could not be taken back through countless ancestors to that initial life form? So perhaps that initial act, accident, whatever, was so unlikely that the odds of us recreating it from inanimate molecules is essentially zero.

    Well, let's continue with that analogy then. A running computer has the cpu taken out, and it stops running. The cpu is then put back in, but nothing happens, because the computer has shut down and must be restarted. If we didn't know anything about computers, we might never know how to restart it, and would conclude (rightly or wrongly) that the computer is more than the sum of its parts. This is a similar situation to the dead amoeba whose processes we would not be able to start, and once again illustrates that my originial experiment would not be very good.

    Yes, I understand. However, I would add the role of the observer. That Meccano set, even if organized according to the relationships of a building, or a ship or windmill, only model those entities because an external observer recognizes the potential functionality of such a relationship. So there remains a missing ingredient, as may be the case with creation of life.

    Yes, I follow your reasoning, even if I don't draw all the same conclusions.

    Perhaps because consciousness is transcendent over the elements. But let me first read the Mind's I (which, unfortunately, is out of print, so I need to go to the library)
     
  20. Aug 17, 2010 #19
    Nesp, you raise a number of interesting points, but I'll leave most of them till you return after dealing with The Mind's I. (I am really sad to hear that it is out of print; it is one of the most stimulating books I have read.)
    One point though:
    There is one important difference, (assuming of course, that the computer really would not start. For example, if it were a clockwork computer and you had removed an item with a spring under stress, then the computer would indeed restart as soon as you reassembled it. The same might apply if reassembling an electrically applied computer included switching it on. I began my computer career in the days of magnetic "core" memory, and often after a power failure a computer would blithely continue with the program that had been interrupted.)

    Anyway, ignoring such eager-beaver computers, the hypothetical amoeba would certainly continue under the postulated conditions. You see, its components are largely enzymes and similar chemicals that will interact immediately if left in juxtaposition. That was why I previously remarked that the experiment would not really be possible; the uncontrolled reactions would soon wreck the system. I think it was Pythagorean who supported this point of view.



    Yes. This raises a number of very ticklish topics. (Don't tempt me...:wink:) The problem with your objection as I see it, is that it does not address the assertion that the whole is the "set of the components, plus the set of the interrelationships, plus the set of relationships with the rest of the universe". The role of the observer is part of that set of relationships. The argument is not affected by the question of whether the "observer" is "conscious" or "subjective" or not; all one demands is whether the history of the universe in that region is affected by any difference in the interrelationships between the parts. As a rule for example, the configuration would affect practically every interaction from tidal forces up.

    But I'll wait with great interest till you have done your reading. If you get your teeth into the book, please give us some feedback; I'd be very interested in your reactions.

    Cheers,

    Jon
     
  21. Aug 17, 2010 #20
    Jon, you are expecting that result because of the life model that you adopt. Not to say that it's a wrong model, just that under a different life model the results might be different. I'd just like to see an experimental demonstration of this model, though we've discussed the difficulty of such an experiment because the chemicals continue intereacting.

    And, to repeat a previous thought, the essence of life might have more to do with those interactions than with the specific chemicals. In a sense life as a whole is a continuous chemical interaction process that began with the first reproducing form in whatever pea soup it began and continues through today. As far as I know, no other life has emerged other than what was produced from another batch of chemicals undergoing internal interactions -- i.e., some other organism. And, like your Meccano set, that process sometimes builds amoebas, other times viruses, or bears, or humans, but it's the same generic process. And perhaps, if we keep an open mind, we might conjecture that once we stop that process in an individual unit, we can never restart it. It's worth a good experiment :-)

    PS I found the Mind's I in a local bookshop, so will be getting it.
     
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