## does evolution violate the second law of thermodynamics?

does evolution violate the second law. from my understanding the second law only applies in a closed system and the earth is an open system with an energy output. (the sun)
so therfore entropy is increasing and it doesnt violate the law
correct or incorrect?
 Yes, you are correct. The theory of evolution no more violates the the second law of thermodynamics than does a tree growing from a seed. The tree is clearly getting more "complex" as it grows. In both cases, evolution and the tree growing, the flow of energy through the system overshadows any local increase in order. People who claim that don't understand either evolution or the laws of thermodynamics.
 Entropy is a tricky thing to get right....e.g. start with the various discussion on this list... You have the basic idea, save that the sun is an energy INput to the earth. The total entropy in a closed system will always increase, but it may not be evenly distributed so there could be pockets of higher and lower entropy even then. In an open system that is absorbing energy, like the earth, the increase could be "passed-off" to the outside somehow. If you expanded your boundary to include the entire solar system you could treat it as "closed" and see a total entropy increase over time. The argument linking life and evolution to decreasing entropy centers around thinking of low entropy as more "organized" -- that a low entropy system has fewer states that it can occupy compared to all the states in the universe. In this sense life is anti-entropic, but remember it is also a local phenomenon. Eventually we will all have to pay the piper. For a more intelligent answer than I can provide, look into the links between thermodynamics, statistical mechanics, and information theory.

## does evolution violate the second law of thermodynamics?

Entropy only applies to simple random systems like gases. There is no solid justification to apply it anywhere else.
So indeed evolution, planet motion and just almost anything interesting has nothing to do with the second law of *thermodynamics*.

Mentor
 Quote by Gerenuk Entropy only applies to simple random systems like gases. There is no solid justification to apply it anywhere else.
That is so wrong on so many levels that I don't know where to start.

 Quote by dcderek24 does evolution violate the second law. from my understanding the second law only applies in a closed system and the earth is an open system with an energy output. (the sun) so therfore entropy is increasing and it doesnt violate the law correct or incorrect?
Almost correct. The Earth is very close to being a closed system. What you meant to say was an isolated system. An open system exchanges mass and energy with its surroundings. A closed system exchanges energy but not mass with its surroundings. An isolated system doesn't exchange anything with its surroundings; it is as if the surroundings don't exist.

That entropy always increases for an isolated system does not apply to the Earth for the simple reason that the Earth is not an isolated system.

 Quote by D H That is so wrong on so many levels that I don't know where to start.
The reason you don't know where to start is simple: No-one has ever given a justification why entropy should be applied to any system.
It's a popular science myth that entropy is everything and something called "disorder".

I mean do you know the proof why entropy works? The proof is simple and shows it's limit. If you don't know the proof, then of course you cannot judge where the limits are. Or can you sketch the proof?

Mentor
Blog Entries: 27
 Quote by Gerenuk The reason you don't know where to start is simple: No-one has ever given a justification why entropy should be applied to any system. It's a popular science myth that entropy is everything and something called "disorder".
Then you should prepare and submit a rebuttal to the following papers:

http://arxiv.org/abs/1003.3937
http://www.physorg.com/news137679868.html
D. Styer, Am. J. Phys. v.76, 1031 (2008).
E.F. Bunn, Am. J. Phys. v.77, p.922 (2009).

Zz.
 S=k*log(w) I think an understanding of this would cure a lot of the problems here.
 Mentor Yes, it would, but this is a major sidetrack from the topic of this thread. On the other hand, the topic of this thread is about refuting a ridiculous creationist argument. The argument is ridiculous for at least three reasons:It is a blatant misrepresentation of the second law of thermodynamics. My air conditioner and refrigerator work quite nicely in spite of the fact that they are reducing the entropy inside my house and inside my fridge. They do so at the expense of energy and of an increase in the entropy of the surrounding environment. This increase in entropy will inevitably exceed the reduction of entropy in my house / fridge. It makes the common mistake of conflating entropy with disorder. Suppose you take a bunch of marbles. You heat some by 5 degrees, heat some others by 10 degrees, cool some by 5 degrees, etc. Now take those marbles, toss them in a bag, and mix them up. You'll have hot marbles next to cool ones, warm ones next to cold ones. Put the bag in a thermally isolated container, seal it, and let it sit for a while. All of the marbles will now be more or less the same temperature. Which is more "disordered": The bag with marbles with a bunch of different temperatures, all mixed up to boot, or the bag in which all of the marbles have a uniform temperature? Entropy is a measure of how well energy is dispersed throughout a system. It assumes, without justification, that life is "ordered" and hence has a higher entropy. This is a major assumption and it needs to be proven.

 Quote by ZapperZ Then you should prepare and submit a rebuttal to the following papers:
I looked at the first papers. The thing is they make no justified derivation like stating (mathematically and well-defined) what entropy means and then showing why it's working.
They rather taylor thermodynamics so make it not fail for biology.

If one wants to apply entropy, then you should first make up your mind what entropy means. And this should be an exact derivation without undefined concepts like "disorder" and so on.

Next you should at least state the model you wish to apply to your test case. I doubt that there is a complete model of biology/evolution(e.

 Quote by Phyisab**** S=k*log(w) I think an understanding of this would cure a lot of the problems here.
I fully agree. The main reason for the popular science confusion is that people don't go deep enough to understand entropy. However, one should understand the Boltzmann equation and set up a well-defined notion of microstate to apply entropy. Next one should proof why entropy increase. It's not an empirical law, but has it's fundamentals in the microscopic processes. And last one can try to identify mathematically exact micro states (e.g. in evolution).
Everything less than that is just popular science for no more than entertainment.

Recognitions:
 Quote by D H [*]It assumes, without justification, that life is "ordered" and hence has a higher entropy. This is a major assumption and it needs to be proven.[/list]
I don't really see how that's a 'major assumption'. When atoms form a molecule, it constitutes a loss of degrees of freedom and hence entropy. All else being equal, the larger the molecule, the greater the loss of entropy. Polymerization is almost never an entropically favorable process. This is basic chemical thermodynamics.

The existence and origins of "life as we know it" hinges entirely on macromolecules: RNA, DNA, ribosomes, proteins. The formation of organic matter from simpler inorganic compounds does lead to a decrease in entropy.

Saying it's because "life is more ordered" isn't a proper rationale though. Nor does evolution in any way imply any kind of continual decrease in entropy. Besides the fact that there really isn't such a thing as 'more evolved' or 'less evolved' (evolution can lead to the gain of genes and the loss of genes), there really isn't any direct relationship between the complexity of an organism and its chemical entropy. We're not chemically very different from the simplest of bacteria. Once again someone's confusing evolution with abiogenesis.
 Admin What always makes me wonder is the fact that the same reasoning - things can't get more ordered - leads to conclusion that it is not possible to make a car, it is not possible to build a house and so on. As it is enough to look around to see those 'impossible' objects, there must be something wrong with the reasoning.

Recognitions: