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Does evolution violate the 2nd law of thermodynamics

  1. Nov 1, 2005 #1
    people who believe in creation say evolution violates the 2nd law of thermodynamics. those who believe in evolution say it does not. who's right? if it does violate the 2nd law of thermodynamics why and how? i just want to know who's right on this issue. p.s. sorry if this has been asked before i'm knew to this forum.
    Last edited: Nov 1, 2005
  2. jcsd
  3. Nov 1, 2005 #2


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    Well, for one, only a few people say evolution violates the 2nd law. Two, evolution isnt a "belief". The claim as ive heard is that since entropy is always increased, complex molecules can't be formed because its a unstable system turning into a more stable system.... or something like that. The explanation I've heard is that while the 2nd law is true for the whole universe, it does not apply to small localized processes. So 2nd law, not violated.
  4. Nov 1, 2005 #3


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    The people who say that life violates the second law of thermodynamics are wrong - they don't understand the second law.

    The short version is that the sun (usually) or some other energy source (undersea thermal vents) is necessary to power life, and that the entropy of the system (life+energy source) always increases.
  5. Nov 2, 2005 #4


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    The Creationist's idea is something of a joke. On one hand, they accept (without really grasping) the physical theory that "entropy always increases." Life, in their view, violates that incontrovertible physical law so therefore we must reject all physical law and invoke the supernatural! I can only be polite and characterize that line of thought as twisted logic.

    Moreover, it doesn't matter to them that the formation of crystals, snowflakes, and myriad other phenomena also lead to a decrease in entropy. They fail utterly to understand that the second law applies only to closed systems and that an amoeba, in and of itself, is not a closed system.
  6. Nov 2, 2005 #5
    As said by those above, but to clarify a little bit, the second law of thermodynamics states that the total disorder of the system must increase for all work processes. It does not say that the disorder of any molecule involved in a thermodynamic reaction must increase.

    If the latter was true, not only would evolution not work but so would many everyday phenomena, for instance, the condensation of Hydrogen and Oxygen gas into water is, by itself a reaction that decreases entropy, (primarily) because it takes three molecules (2 H2 + O2) and yields 2 molecules (2 H2O) (and also because it is converting from gaseous to liquid phase, and for some other reasons). However, this reaction is exothermic, meaning it gives off heat, that heat, on average, increases the entropy of the surrounding system (the rest of the H2 and O2 gas, the container the reaction is held in, etc.) and increases entropy more than the reaction decreases entropy for the original reactants, thus overall, entropy increases, and the reaction is allowable by the second law of thermodynamics.

  7. Nov 2, 2005 #6
    Hello! well this is my first post since I've registered here a year ago!
    Anyway I think it is a quite interesting point of view concerning this 2nd law of Thermodynamics and by logic seems that the opinion that says life violates the 2nd law of Thermodynamics is wrong, seems quite true for me.
    Well, I've been always thinking of a way to combine both things, religion and science because I believe both are true but what makes them different are some hidden aspects that still we don't know.
    I really don't know why should we judge life and put it under the microscope of thermodynamics or any other "systematic" theory. Shouldn't be really a question of biology and anthropology more than thermodynamics?
    I always asked myself, if the theory of evolution is true, then why do we still have monkeys and chimps ..etc? Why they didn't change with us and became like some other species of the human race? Up to now I didn't read anything that links the history of Neanderthal man with the homosapiens race ... both seem to be completely different races.
    I won't argue around my religion, although in fact according to my religion we have the belief that before Adam and Eve there were other living beings with significant intellegence, but let's go by that just by some logic.
    If you don't believe in a Creator, then why the world seems so systematic? and yet if we believe in evolution, then why our race didn't develop itself against certain diseases or change shapes like what happened to our ancestors?
    Anyway, I think for evolutionists still there are lot of questions not answered and yet there are also other questions to be answered for people like me that believe there is a unique story behind the evolution.
  8. Nov 2, 2005 #7
    The great thing about thermodynamics, the thing that led Einstein to remark on its greatness, is that it applies everywhere.

    It isn't a case that one day all subsequently born babies are a different species. Mutation occurs all of the time - every child born will have DNA that has mutated slightly from its parent. Such mutations only become noticeable when they have some impact on the animal's fitness. For example, sickle cell disease is a hereditory disease that protects against malaria - a handy illness to have in some corners of the world. Even this does not a new species create - those with sickle cell disease live side-by-side with those without. They have an advantage over their non-diseased neighbours, but only in their immediate environment. In, say, America, sickle cell disease is a disadvantage because you are not likely to catch malaria. Furthermore, there is no anatomical difference between someone with and someone without the sickle cell gene - only a genetic difference.

    It can and has come about that some mutation(s) have such an impact on a creature's fitness for survival in their environment that they thrive at the expense of their neighbours in that environment alone. The parent species may die out in that environment, but still be found in others where their fitter descendants are not found.

    By way of illustration, when grey squirrels were imported into the UK, they were so much more well suited to their new environment than the indigenous red squirrel that the red squirrel has all but died out in the UK. However, there are no grey squirrels in the Isle of Wight, so the red squirrel still thrives there.

    In the case of home sapiens, it is believed that the evolution of the species went hand-in-hand with with a change of environment, the mass exodus into the plains of Africa. It makes no sense, then, that their ancestors would die out.

    In summary, the parent species doesn't die out when another species evolves from it unless that child species yields such a survival advantage that its success leads to the extinction of the parent species. Even then, it would have to lead to the extinction of that species in all of its environments, which is highly unlikely, since the child species will have evolved only once.

    They share a common ancestor, but one did not evolve from the other.

    Isn't it odd that the only human male and the only human female needed to differentiate each other with the use of names. For whose benefit? Oh, religious people, I guess.

    Because of the nature of physical law. It doesn't matter how many times you raise a rock 1 metre above the surface of the Earth and let go, it will fall to the ground in the same amount of time. Therein lies the systematic nature of the Universe (which isn't all that systematic anyway).

    See the bit above about sickle cell disease. Also, mutations are random. You can't choose to evolve.

    There are a lot more answers already out there than creationists give evolutionists credit for. The problem is twofold: (1) few creationists understand the intricacies of evolution enough to understand where a problem does or does not lie; (2) creationists tend not to believe that a question has been answered unless the answer given is the one they wanted - it has something to do with faith.
  9. Nov 2, 2005 #8


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    It may be quite "true" to you if you do not understand what the 2nd Law is and under what condition it is applied. Ask any physicist if such contradition is true, and you will get a good giggle. This issue has been addressed many times (even in my journal entry under "Imagination without knowledge is Ignorance wanting to happen"). I seriously suggest you figure this out and not propagate this myth any further.

    It appears that you have missed a lot of arguments that have addressed practically all of your "concerns". The US National Academy of Science has an extensive guidelines on addressing such issues. This is just ONE example of the resources available that have countered these false arguments brought up because people do not understand intimately the science involved. Even if choose not to accept such explanations, you should at least know they exist and not perpetuate the argument that "a lot of questions not answered". They have been answered. However, whether you are equipped to UNDERSTAND what has been answered is another matter.

    I am not going to address the validity of the acceptance of your "belief" when compared with emperical evidence. It is because this thread has the potential of slidding down a very slippery slope of violating PF Guidelines. I strongly suggest you re-read that in case you have forgotten it from a year ago, or since the last upgrade. I will also remind you that this thread is in the PHYSICS section of PF, and so arguments must be based on physical grounds and question of "biology and anthropology" are NOT more important than thermodynamics.

  10. Nov 2, 2005 #9
    Hello again
    well just first of all seems my sentence was misunderstood by ZapperZ. What I meant about life and the 2nd law of thermodynamics is that indeed life doesn't violate that principle in general, maybe I should've reformulate that sentence somehow.
    Still, didn't know that physics laws are there because they are there ...
    well, seems they are helping each other in some sort of way!
    As far as I know is that my ancestor monkey lived with others in one world and in some corners with others so still i can't get the idea that only one of those evolved to man while the others are watching.

  11. Nov 2, 2005 #10


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    You are more than welcome to pose this question in the Biology section. Or better yet, you should go to that forum and do a search to see that your question may have been sufficiently answered. You may find that you understanding of what "evolution" is and the mechanism that drives evolution is faulty.

  12. Nov 2, 2005 #11

    Hans de Vries

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    Evolution happens right under our nose. It has never gone so fast as today
    with all the breeding going on. The most a creationist could claim is that
    evolution doesn't go all the way back.

    The 2nd law of thermodynamics is based on probability considerations.
    It's in some respects more a law of mathematics than physics:

    It's easy to throw a coffee cup into pieces (1), but the other way around,
    throwing the pieces back into a whole cup (2) is virtually impossible.
    But the latter isn't any harder than throwing a cup twice in exactly the
    same pieces scattered exactly in the same way (3).

    The difference between (1) and (2,3) is that all end results count in (1)
    while only a single end result counts in (2,3) so the first has a much
    higher probability.

    So, yes, evolution needs luck and thus many tries. That's why it took a
    billion years with the first very simple steps taking most of the time.

    The 2nd law is also often the center of (vague) philosophical discussions
    about the "arrow of time" often overlooking the probability aspects.

    Regards, Hans
  13. Nov 3, 2005 #12
    people who belive in creation are often stupid people who dont understand physicals law exept when they want it and then its often wrong. Its in a closed system entropy increase, earth isnt a closed system, we get high quality energy from the sun, life transform it into relative high quality chemical energy, the entropy have increased, but cause of the flow of high energy into earth its possible to advance.
  14. Nov 3, 2005 #13


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    That may be true, but resorting to ad hominem certainly isn't going to bring them around to your way of thinking, and accomplishes nothing. No matter how ridiculous and ill-founded the assertions of their opponents are, scientists shouldn't have any need to resort to such tactics, not even to retaliate against any such attacks that might be heading their way. Why not follow the example of others in this thread and present sound, well-reasoned arguments, along with clear explanations of misconceptions that are absent of any form of judgement?
  15. Nov 3, 2005 #14
    First off, lets not degenerate into ridiculous semantics. The purpose here is to lay out valid arguments, not "people who believe in creation are often stupid".
    Second, this thread started out with a question about the second law of thermodynamics. Since it is logically proven that evolution does not defy it then there is no more need for pointless rehtoric. I would like to say however, that if you believe that creationists place their entire theory the idea of thermodynamics, you are sorely mistaken. True, it is one of their claims but not the only one.

    Most of the arguments against evolution stem from the evolution of species, not the universe. They claim that the odds of random DNA change result in a positive result, and having that change stay in place through generations, is astronomical. To have enough of these mutations to change a species for the better is, while in theory possible, is to hopelessly impossible to ever have credibility. They say, think about the complexity of an eye, or the brain. Think about everything that makes them what they are, the countless connecting pathways and mechanics, makign them all work together properly. The brain itself, which we truly have very little knowledge about, is so complex we might take several tens of thousand of years to fully understand it. How can this have happened because of a mistake, an accident?

    The other argument is that we should have the missing links walking around. If we have chimps and humans now, obviously some evoled and others didn't. Why, halfway through human evolution, didn't some monkeys start evolving, resulting now in living links between the species? Not only should there be an abundance of missing links fosils, but they should be alive now, waking the planet.
  16. Nov 3, 2005 #15


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    I think you have brought up one of the main arguments of ID'ers that, in my opinion, has not been sufficiently addressed by biologists and statisticians to the general public. Many are highly persuaded (or seduced) by such an argument. I think there is a major lack of "order of magnitude" undertanding among many where simply a handwaving argument is sufficient to convince someone that so-and-so is "highly unlikely".

    There are several ways to address this, and since this is still in the physics section of the forum, we will stick with either physical arguments, or use our physics expertise in tackling a problem.

    1. How "unlikely" is the evolution into our present form? I have seen several estimates (and they ARE estimates in the roughest sense) of the chances of DNA's forming into its current form. Sure, the probability is very small. However, would anyone like to look at the probability of finding the top quark at the Tevatron several years ago? Let's see, they found... what, 8 events out of how many gazillion, gazillion events? And this is not counting those that are vetoed outright. Particle collider experiments are the MOST demanding scenario in terms of data acquisition, storage, and processing speed because of the mind-boggling quantity of data being gathered in just a fraction of a second. Someone should show these ID'ers the probability of finding a "positive" event out of all of these gazillion interactions and COMPARE that number with the numbers they're putting out for the DNA formation. Why this hasn't been done, I don't have a clue.

    The main point here is that just because the probability "order of magnitude" appears to be miniscule doesn't mean we have not seen such occurence already, even within our lifetime. When the probability for something to occur is small, but there are a gazillion candidates, the phase space for that to occur is still reasonable enough that it CAN (and has) happened.

    2. Often, the calculation of such probability itself is highly dubious. It assume that one starts off already knowing the final phase space that one has to end up with. Let me give an example. Let's say I start off with 4 letters, A,B,C, and D. I have 10 slots to fill this letters with (repetition is allowed). I want to know what is the probability that, after a random selection, I end up with a sequence that such as


    One can do the straightforward calculation there. One can accurately argue that the phase space (or probability) of getting such a sequence is small. However, is this really what is going on with the evolution process? I would make a definite claim that it isn't.

    First of all, the formation of our DNA doesn't not happen all at once at the beginning of the evolutionary process. Natural selection dictates that based on the external ecological pressures, there will be traits that will be more favorable than others. Now unless I slept through reading the formation of our universe and earth, the earth a LONG TIME ago is not the same earth that's here today. There is just a different ecological pressures when it is mainly water/molten rocks/etc. Our current forms are just not "favorable" back then!

    As the environment changed, so does the external pressures, and different traits became more favorable. In other words, the DNA selection changes gradually. So maybe, using my example above, you have filled only the first 5 sequence of BBDBD_____. Now, the probability phase space to end up with BBDBDAEDDA is no longer as large as in the beginning. You have already established the first 5. It's like flipping a coin 4 times and asking for the probability that you end up with 4 heads. While the probability at the start is of course (1/2)^4, if you have already obtained 3 heads, then the probability of getting all 4 heads is just 1/2.

    For some reason, I haven't seen this argument put forth convincingly to people who are being seduced into believing in this probability game.

    3. There is also the major assumption that ending up with BBDBDAEDDA sequence is the ONLY possible option. I mean, at the very beginning of the selection, how do we know that BBDBDAEDDA is the ONLY sequence that would produce anything worthwhile? Now, if we question that, then let's play this game.... Let's say I end up with ABACCAEDBB. There! I just got a sequence! Now, if we look at it AFTER THE FACT, someone can say

    "WHOA! The probability of getting that sequence is VERY low. How'd you managed that?"

    I can just walk around and say "Oh, I'm very good at this" or "Well, I'm just a very lucky person".

    Yet, I didn't plan on getting that sequence. It just came up randomly. Obviously, someone who looks at it AFTER the fact, thinks I'm very lucky because it is VERY highly unlikely to get that sequence. In fact, ABACCAEDBB could be a new creature capable of producing anti-graviational effects via zero-point fluctuations! Remember, evolution never had a "final design" in mind. It is simply a trait being selected at that given moment due to all the external pressures and the available nitches in the ecology. So the sequence could easily be something else if our earth made a right instead of a left turn at Albuquerque.

    Er.... Oy, this has gotten longer than expected. No one would read something this long anyway.....

  17. Nov 3, 2005 #16


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    Wrong. I don't usually read things that long, but that was a great post.
  18. Nov 3, 2005 #17
    Evolution does not violate the Second Law.

    One way to define life itself is "the postponement of entropy by biological processes." So it's debatable whether it even applies in the first place.

    The claim comes from the observation that evolution tends to result in a more complex organism. But the existence of a process that results in greater order and greater complexity does not, in itself, violate the Second Law. Look at the construction of a fighter plane out of disparate mineral ores, organic substances and synthetic substances -- surely the process that created the much greater order and complexity of the aircraft does not, by its existence, negate the Second Law.

    In other words, it's a logically flawed claim. It is made by those who either do not understand what the Second Law means, do not understand what Evolution means, or are just being disingenuous.
  19. Nov 3, 2005 #18


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    Speaking of probabilities and likelihoods...

    The odds of drawing any particular 5-card poker hand are smaller 1 in a hundred million. But every time I'm dealt a hand, I don't marvel at the extremely low likelihood of my getting dealt that hand; and I don't dismiss the reality of my holding that hand just because the odds of my getting it are so low.

    And to take this a step further, the odds of being dealt a specific hand is independent of the hand - any particular royal flush is just as likely as any specific arbitrary hand. Now, that royal flush looks highly ordered, but that doesn't make it less likely to get than any other particular hand.

    Another thing I want to discuss is the time-evolution of a sytem. Darwinian Evolution Theory requires a mechanism whereby certain specific outcomes evolve differently from other outcomes. In other words, all outcomes do not evolve identically, and this "selection" helps improve the odds of having complexity evolve from simpler things.

    Here's an example to illustrate this selection : Take a big box and fill it with two sizes of balls - 1 inch marbles and 5 inch balls. Chuck all these balls randomly into the box. Now, continuously tap the box (gently), so the balls can rearrange themselves. Slowly, you'll see the smaller balls settle to the bottom, with the big ones above them. Given enough time, all the little balls will form into a lower tier, and the big ones into an upper tier - a perfectly ordered state ! What caused this ordering is that some balls - the little ones - are better than others - the big ones - at finding their way through openings and getting to the bottom. If it were equally easy for both kinds of balls to head for the bottom, the probability of arriving at this ordered state would be incredibly small. But because of this mechanism of selectivity, this ordered state is virtually a certainty in the long run.
  20. Nov 7, 2005 #19


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    Gokul43201 -- Great post. Indeed, the very notion of an event's (nonzero) probability presupposes that the event can occur. If, for some reason, the event cannot occur, then, surprise, the probability of the event is zero. To suggest that very low probability events cannot occur without some form of intervention is disengenuous at best; dishonest at worst, and is just plain wrong to the core.

    ID? Who want's such a pessimistic -- life's too complex; just give up trying to understand -- spin centered doctrine?

    Reilly Atkinson
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