What are the Odds of life coming into existence by chance alone?

Discussion in 'Biology & Genetics' started by Alan McDougall, Jul 26, 2012.

  1. Grumpy Curmudgeon of Lucidity Valued Senior Member

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    Captain Kremmen

    I was simply pointing out the idiocy of those who argue that the Second Law precludes life coming from natural forces and conditions. The Morley experiment showed that energy and chemistry produce amino acids naturally(moot, since amino acids were delivered to Earth by meteorites already ready for assembly into proteins). It's not that more energy equals more life, it's that it is not necessary that the energy balance be self contained as your statement said. IE the Second Law has nothing to do with whether life can be produced by chemistry.

    Grumpy

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  3. Aqueous Id flat Earth skeptic Valued Senior Member

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    Nevertheless the creationist argument that order out of chaos is improbable is kind of ridiculous, don't you think?

    And as for crystal symmetry, that's just the intrinsic nature of chemical bonding, and the equilibrium that comes from conservation of energy as charge distributes itself and leaves the material neutral. It's all explainable by the same kinds of principles - science, nothing more. But creationists don't usually challenge the principles that apply to inert objects. They're concerned with the ones that lead to identifying who they themselves are, what they are made of, and why.

    It seems to have run a course from superstitious myths, invented to explain phenomena for which they had no science, to a neurotic terror about the sense of self. Is this religion, or merely an unclassified form of mental illness?
     
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  5. Captain Kremmen All aboard, me Hearties! Valued Senior Member

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    Yes, I would agree. It is unwarranted for a theist to assert that a problem, which as yet has no scientific answer, is a proof that God interferes with natural processes.
    This is one of the gaps that creationists seize upon.
    It's a good one though.

    The answer can't just be a matter of mixing the right chemicals and applying heat.
    Pots have been boiling away for years now.
    Something else must act as a catalyst or as a substrate which makes the formation of proteins easier.
     
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  7. FTLinmedium Registered Senior Member

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    Your question was as such:

    Where you obviously meant the second law (and corrected yourself later- which is fine).

    You now seem to have changed your question to protein formation in the process of abiogenesis- which is not considered part of biological evolution proper, but rather another related field (biological evolution only takes over once there's a fundamental biology there to evolve).

    In the case of biological evolution, sunlight is the obvious source of power for the system- through photosynthesis (or chemosynthesis). This is something that creationists literally do not understand. They think a baby being born violates thermodynamics because it is 'order from chaos' and they don't understand the concept of an open system.

    If you meant abiogenesis to begin with, the question isn't as simple as it appeared (but very inaccurately formulated).

    You should have said:

    "I have no problem with abiogenesis, but it seems to operate in the face of the second law of thermodynamics without a clear mechanism by which outside work can be directed into the system (where photosynthesis was not yet available)."

    What you said implied a problem with evolution proper, as if you didn't understand how sunlight becomes plant matter (higher frequency light to infrared) which is eaten to become feces (broken down structures releasing usable power)- all a process of entropy, which more than makes up for the synthesis of biological molecules and the general process of growth, movement, and reproduction that fuel evolution. Most creationists literally do not understand this point. That is what they are complaining about when they mention the second law of thermodynamics.


    Did you ask this question clearly somewhere else? Did you change your question without restating it? Or did you just miscommunicate your question that extremely?

    If you asked somewhere else, that's fine. If you chanced your question because you learned more- that's great- but please own up to it rather than accusing others of 'not understanding' when you aren't making yourself understandable.

    If it's the last point- you need to ask your questions more carefully, and doing so usually requires some basic knowledge of the subject (which you seem to be working on acquiring now, which is respectable- but it would be a good idea to read before trying to have an argument about something like this).

    The process by which the first amino acids could have formed in abiogenesis is an entirely different question from that which you asked.
     
  8. SciWriter Valued Senior Member

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    The capability for life was inherent in the universe from the beginning, in how the universe's form was, given, too, that there could be a place like Earth that had all the right conditions for it, which was likely because the universe is really large, another requirement, and that the universe could last for billions upon billions of years to allow time for life to evolve…
     
  9. Fraggle Rocker Staff Member

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    The Second Law says only that entropy tends to increase over time. It does not say that this increase is monotonic.

    Both spatially and temporally local reversals of entropy are possible, and there is no limit on their magnitude.

    Life itself has been concisely defined as "a local reversal of entropy." Organisms destroy the organization (i.e., increasing the entropy) in the space around them, in order to increase the organization (i.e., decrease entropy) inside themselves. A trivial but familiar example is one animal killing another (a dead animal is certainly less organized than it was when it was alive, a clear increase in entropy) in order to ingest its molecules and use them either for energy or growth (either of which is an increase in organization and therefore a decrease in entropy). Organisms of the other five Kingdoms (plants, fungi, algae, bacteria and archaea) are not generally so violent in their metabolic processes, but they do the same thing in more peaceful ways. Plants, for example, absorb the high-frequency electromagnetic energy from the sun and convert it into much lower-frequency energy (a decrease in energy differential is a textbook example of an increase in entropy) for the metabolization of carbon dioxide and other molecules they suck out of the environment in order to increase the number of cells in their bodies, which is an expansion of organization and a textbook example of a decrease in entropy.

    Evolution is simply one of the defining processes of life (along with growth, feeding, reproduction, response to stimuli, regulation of an internal metabolism, etc.) so there's nothing anomalous about the fact that it, too, operates by reducing entropy locally.

    I have often postulated that the Big Bang itself can be analyzed as nothing more than a very large, but both spatially and temporally local, reversal of entropy.
     
  10. Captain Kremmen All aboard, me Hearties! Valued Senior Member

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    @FTL
    Point taken.
    Yes, I did mean Abiogenesis. I thought that that was the subject of the thread.

    Lets go back to my first post on this thread.
    I first quoted from the OP:
    "There are claims by some disbelievers in evolution that the odds of life evolving by chance are so high that the probability is zero"
    From this, I gathered that he meant the earliest forms of life.
    Perhaps I'm wrong about that.

    Following quoting the OP, my first words were these:

    If you have infinite Time, then the odds of producing life, if life is possible, which it clearly is, are certain.
    However, this Universe had a specific beginning, if you accept the BB theory, (which I do) and did produce life.

    I cannot see how Physics can cope with evolution.
    The earliest forms of life require an increase in complexity, without any compensating increase in entropy.


    I have since accepted the point that complexity and entropy are not equivalent opposites, but I don't think that I have changed my standpoint much since starting the thread.

    Perhaps Alan can clear up the point on Abiogenesis.

    @Alan
    Did you mean the thread to be about the genesis (pardon the term) of the earliest forms of life and their prototypes?
     
  11. FTLinmedium Registered Senior Member

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    Captain Kremmen, thank you for clarifying.

    Above, you can see that Fraggle Rocker read the question the same way I did- and of course didn't answer what you were after due to the confusion (Good answer though, Fraggle Rocker)


    As to your question:

    Energetically unfavorable things happen all of the time by happenstance- thermodynamics is not absolute, but statistical in nature. On the very small scale, quantum probability takes over and we can see apparent violations because entropy itself is merely a derivative of probability.

    Remember, all reactions in chemistry are inherently reversible. A high energy photon plus the right combination of carbon, hydrogen, and oxygen can yield a carbohydrate and a low energy photon- likewise a low energy photon and a carbohydrate can break down into a combination of carbon, hydrogen, and oxygen and yield a high energy photon.

    Everything in Chemistry is reversible- time is merely the direction of greater probability- entropy merely representative of those more numerous outcomes vs. those less numerous ones in terms of probability.

    Of course, this does make the formation of any one energetically unfavorable compound less probable for any given time frame. But this is not really an issue, as the improbability is not on an astronomical scale considering the number of reactions we're talking about.

    That's not necessarily how I think life formed, but it's entirely viable.

    As to the boiling pots: they are very small pots. The ancient environment of planet Earth was substantially larger. Rolling a hand full of dice repeatedly and trying to get one die to display a six a hundred times in a row is going to take a very long time. Rolling an entire ocean of them over and over again will take substantially less time. It only has to happen once (though in practice it probably happened many, many times in different places to produce virtually identical early life).


    Personally, I favor chemosynthetic origins of life- whereby the first living molecules were self replicating catalysts for the breakdown of unstable hydrocarbons into more of the same catalyst. The formation of the first one being energetically favorable (because the process itself is), but simply less probable without a catalyst to start it off.

    That doesn't matter, though. The bottom line is that however you look at it, it's entirely possible, and only a minor hurdle of improbable circumstances to overcome, which is trivial given the massive size and duration of the original environment.
     
  12. Captain Kremmen All aboard, me Hearties! Valued Senior Member

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    Chance configurations must play their part, but not by producing the nearly impossible.
    I think that Abiogenesis requires the occurrence of a fairly simple molecule which interacts with its environment to reproduce and allow variation.
    Life with a great degree of certainty did not begin with some pot producing DNA. (RNA?)

    My conjecture is that there must have been a development of a simple natural template which acted as a catalyst,
    enabling proteins to form, duplicate, vary, and set down new templates.
    What form might that template take? Crystals? Primitive Membranes? Minerals?

    It's a lovely problem for someone to solve.
    And shouldn't be dismissed because it is one of the gaps that Creationists love so much.
     
  13. The Marquis Only want the best for Nigel Valued Senior Member

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    The odds of winning lotto in Australia are about 1 in 8,145,060.
    Someone wins nearly every week.

    How many planets are there in the known universe? How many more are there we don't know about? Those are the players.

    Life is the winner.
     
  14. Fraggle Rocker Staff Member

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    You're still not coming to terms with the mathematics of very large numbers. The phrase "nearly impossible" is "nearly meaningless."

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    Something may have a relatively high probability or a relatively low probability, but as long as it's not zero, it's possible. If something is possible, by definition that means that it may happen. If you have a sequence of events which all have low probabilities, then the probability that they will all occur is even lower, but it can still happen.

    When your time continuum is measured in billions of years, the sequence of events can even happen multiple times.
    Your entire argument is based on an insistence that something with a very low probability will never happen. You're still confusing "low probability" with "zero probability." When you're talking about tiny events taking place over and over and over again, over a span of billions of years, that confusion is what makes your assertion wrong.
    By all means test your hypothesis. Look for these templates. But please bear in mind that it's only a hypothesis, so you must be open to the possibility that it may be false. If you insist that it must be true because the alternative must be false, despite the fact that it has not been proven false, then your practice of science begins to resemble the work of a creationist a little more and that of a scientist a little less. Don't fall into that trap.
    Which illustrates my point. They all believe that a series of events, each of which has a low probability, will itself have a probability of zero. They're wrong. Please don't borrow their wrongness.
     
  15. FTLinmedium Registered Senior Member

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    Fraggle Rocker answered this well.

    It's simply not a problem. Creationists see it as a problem, but that does not make it so. Creationists also see "side by side" dinosaur and human footprints as a problem. They see imagined "gaps" in the fossil record as a problem. They see the lack of ape men as a problem. They see the existence of monkeys as a problem (if man came from monkeys, why are there still monkeys??). They see bananas as a problem.

    They see problems everywhere because they want to see problems everywhere.

    Moreover, none of them are problems- "solving" non-problems for them doesn't really help matters, because they are not looking for the solutions.

    If they want to disagree with evolution, they'll disagree with it. It's a free country, so that's their right if they don't want to accept it.

    Some people still believe the Earth is flat too. I don't agree with it, but it's their right to believe it if that's what they want.

    The facts are there- and both overwhelming and irrefutable- for anybody who wants them. Adding something like this isn't going to be a silver bullet for education in evolution if nothing else is.

    And as Fraggle Rocker mentioned, your attitude towards the problem you think exists is a little closer to creationism than science- it's not a 'this must be true' situation. It's a possibility- one of many.

    If you can find something like this- that's awesome!
    If you can't- we have perfectly viable theories for how it happened which are entirely plausible.

    There's not a lot of focus put into abiogenesis because it simply is not that important. Evolution of existing life is both far more interesting and far more useful to us.
     
  16. Cyperium I'm always me Valued Senior Member

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    But at least tell me which assumptions are inaccurate.

    You said;

    ``Anywhere on the surface of the Earth, the environment is too contaminated with existing life for new forms to thrive (and today, the conditions may no longer be right for it due to the changes brought about by the existence of life- particularly, too much oxygen). If there is a niche anywhere accessible, it is probably already filled.´´

    A culture of single cells grown from only one cell would grow large pretty fast, there isn't much difference between that single cell and a new form of life, it is also pretty defenseless. There is competition of resources though, but given good initial conditions then I think it should be able to survive. Is oxygen not good for abiogenesis? I don't get what you mean by "too much oxygen", why would that be a bad thing for a new form of life?

    You said that there are a lot of crossing of DNA so that the lines blur between many different origins. They would probably do that if the differences between the DNA was small, but I don't think that they would blend if they were too different.

    I think it's wrong to say that the environment is too contaminated with existing life. How would you know that? Species get exstinct and when they do they leave room for other organisms, not to mention the various disasters that have happened during the history of the earth which have erradicated almost all life. Life goes up and down, giving plenty of oppertunities for new life forms to step in amongst the others (in the void left by the extinct). Instead it seems that only new species have filled those voids, never any new life forms. It doesn't need to be a big disaster either, life fluctuates naturally also because of diseases and environmental changes and you name it. There isn't a constant through time that all niches are filled or that the oppertunity for new life is always full.

    If you don't have time then I beg that someone else please explain to me what he means.
     
  17. FTLinmedium Registered Senior Member

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    Hi Cyperium,

    I have a few minutes now, and I think I see where your confusion is.

    This could not be farther from the truth. The difference is more extreme than the difference between and elephant a maggot.

    Modern cells have membranes or tough cell walls, they can hold in water, and use pumps to control their homeostasis, they have chemical defenses against oxidation, melanin and other pigments to defend against ionizing light, special proteins to prevent damage from cold, the ability to move and sense their surroundings to a small degree, produce toxins and poisons to wage chemical warfare against enemies- make themselves poisonous so they can't be eaten- and even form tough impermeable shells resistant to light, dehydration, freezing temperatures, and heat.

    And that's only part of it off the top of my head. Cells are fortresses, evolved over billions of years for survival on this planet- and with arsenals of chemical weaponry.



    Early life had none of these things. Zilch. Nada. It was just a self-replicating protein, only slightly more complex than a prion.


    Oxygen is lethal to all living things and absolutely destroys DNA- it is a ravenous and highly damaging molecule. That is, unless the DNA is protected and encapsulated, and the organism has evolved carefully regulated systems to defend it from oxidation and repair the damage.

    Many bacteria are killed almost instantly by the oxygen in the atmosphere- these are the types of bacteria that do not have defenses against it. Look up 'Obligate anaerobic bacteria'

    This would certainly be the case for new life.


    Turns out not to be the case; particularly for microorganisms. DNA is quite promiscuous that way; it gets everywhere. This is compounded with symbiosis.


    There has never been such a disaster. Some disasters have killed a large majority of animal and plant life- bacteria is prolific and durable. It exists in some of the coldest and hottest places on Earth- in ice, and even under the crust of the planet.

    Bacterial life is everywhere. A new life form isn't going to suddenly become a large animal- its competition is bacterial. And in that domain, the competition is overwhelming and ubiquitous.
     
  18. Grumpy Curmudgeon of Lucidity Valued Senior Member

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    Cyperium

    When life began on Earth there was no free oxygen in the atmosphere, the first life was anaerobic and oxygen was at best a waste product that quickly got snapped up by iron or an outright poison, destroying the lifeform. Only after photosynthesis started did free oxygen become available in the ecosphere and as it's concentration went up most lifeforms died, only those that evolved the ability to deal with it survived. Oxygen is a very energetic chemical that disrupts many reactions in simple lifeforms. The chemistry that led to life is probably not possible in an oxygen atmosphere.

    The molecular structure of DNA is the same in all Earthly lifeforms, we've put spider DNA in goats to produce spider silk in their milk. There are no basic differences in the DNA molecule in any creature.

    New life would stand no chance to survive in competition with even the simplest lifeforms alive today, they would be food, not competitors and with free oxygen floating around, they are not likely to come into existence in the first place. Every species developed from previous species with mutations, descent with modification is the source for all extant lifeforms.

    Grumpy

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  19. Aqueous Id flat Earth skeptic Valued Senior Member

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    For the cyanobacteria, it's suffocating. They require CO[sub]2[/sub]. Other early forms may have relied on the whatever gases were more prevalent in the primordial atmosphere. There are various scenarios - methane and ammonia were once considered to have been abundant. Another scenario is hydrogen, nitrogen and CO[sub]2[/sub].

    I'm not sure about blending, but there does seem a high probability for interaction between them. The mechanisms for gene expression, and the way the helix divides during cell division are some of the weird but essential mechanisms of DNA that may have been already working by the era of the first cell. This might be attributed to early DNA/RNA/amino acid interactions in the prebiotic era, since it's hard to imagine any other interaction that might lead to these essential mechanisms taking root the way they did. (This is all speculation of course.)

    Abiogenesis is probably different, though, since it happened under conditions that were different. We know the atmosphere was less rich in oxygen, for example. The Miller experiment (which demonstrated how amino acids might form spontaneously) was done under the assumption of a methane-ammonia atmosphere, in brine with simulated lightning. If anything it serves as an example of what wouldn't be possible in the more modern conditions on Earth, especially after the Great Oxygenation Event.

    Sometimes creationists like to claim that Earth is uniquely situated for the origins of life because (and then they list things like distance from the sun, mean temp., etc.). But when you hear them say "oxygen", that's where they need to be corrected. By the time oxygen was abundant, in all likelihood primitive organisms were already "created" and were then already evolving. (I think it's still widely held that the cyanobacteria built the present atmosphere.) You're right that it yields a lot niches to be filled, but this would better relate to evolution than abiogenesis.
     
  20. Aqueous Id flat Earth skeptic Valued Senior Member

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    Hah - we were composing an replies at about the same time. I like your answers better.
     
  21. Cyperium I'm always me Valued Senior Member

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    Thank you for all of your answers, I think I can see now that new life could come to exist but would be wiped out almost immediately, either by oxygen poisoning or (if it somehow could stand that) by other organisms destroying it. I guess that the odds for life to spontaniously form with the defenses are pretty low even given such a large time and space.
     
  22. wlminex Banned Banned

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    Capt Kremmen: "Something else must act as a catalyst or as a substrate which makes the formation of proteins easier."

    IMPO: Emergent quantum patterns via Casimir-like effects that are impressed on organic matter?
     
  23. wlminex Banned Banned

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