Thermodynamics and Evolution

The Earth being an open system doesn’t automatically exclude it from the 2LOT. What you have to do is consider the Earth and Sun as a single closed system.

Do heat and light have a big enough impact on life,

I don’t know what a ‘big enough’ impact is, but they certainly have a BIG impact. Most things on Earth either directly convert the sun’s energy to food, or else feed off things that do.

What we have to ask is: does the increase in the sun’s total entropy as a result of its fusing hydrogen, PLUS the Earth’s increase in entropy from the breakdown of radioactive isotopes at its core, at least equal the overall decrease in entropy of the Earth’s biosphere? I think you’d be hard-pressed to argue that it doesn’t.

The AiG article essentially makes a more sophisticated version of Duance Gish’s argument that “an energy directing and converting mechanism is required”, with a little of Hoyle’s ‘Boeing in a junkyard’ argument thrown in. It’s nothing new. The answer is that Gish’s mechanism, or AiG’s machine, does exist, in every single cell: the chemical synthesis engines that power every living organism.

George,

You said:

“The answer is that Gish’s mechanism, or AiG’s machine, does exist, in every single cell: the chemical synthesis engines that power every living organism.”

I’m curious to know why this is such a profound statement? As if AIG or anybody else doesn’t already know it?

Of course energy conversion mechanisms exist. Pointing out that they exist not only does not solve the problem at hand, it merely restates (or compounds!) the problem.

The standard creationist-evolutionist argument is kind of funny to watch:

“Bodies don’t spontaneously generate an exit heat flow.”

-”Haven’t you seen refrigerators?”

“Yes. That is why I said that bodies don’t spontaneously generate an exit heat flow.”

-”Yeah, but refrigerators exist.”

“Um, we’ve already settled that. OOOHH! Are you actually suggesting that refrigerators are spontaneously generated?”

-”No, just giving an example of a system with a directional exit heat flow.”

“So, you’re basically conceding that *designed* systems can have exit heat flow…”

- “I’m not going to argue with you, you’re just perverting thermodynamics.”

Sorry to characterize any anassuming atheists out there… I just haven’t ever seen much better than the above.

Hm. There *are* simple examples “local entropy reducers”. My favorite example (of many) was always phospholipids. They’re simple little chemicals, one carbon tail with one phosphoric head; left on their own in any kind of random setup, they’ll naturally move in towards eachother, heads touching heads, and tails touching tails. They’ll create full barriers to repel water, vesticles, and plenty of other very interesting, well-ordered, and sometimes impressively complex structures like grids or cylindrical containers, given just enough thermal energy to reach eachother. They’re simple enough and stable enough that they almost certainly were formed by basic chemical reactions long before life got started.

Specific examples aren’t really that interesting though. It’s always easy enough to go “Well, sure, but that doesn’t apply to the situation at hand of DNA, does it?” The thermodynamics of self-assembly and complex structures, though, *that’s* what’s really important to consider all sides of, I love debating their meaning. Sure, the second law always applies in one form or another. But there’s *other* thermodynamic laws that let even very simple molecules act in those complex ways.

Just as critical as the law that “Entropy always increases”, is that “Free energy and potential energy mimimizes itself”.

I like to think of them as competing proporties often. Entropy will naturally cause more random thermal motion and ‘disorder’ … however, at the same time energy is trying to minimize itself, and most low-energy states tend to be well-ordered (Things usually attract to similar things, for instance, a kind of self-sorting, and chemical bonds achieve their lowest energies at nice regular patterns)

So, random collections of many kinds of molecules (surfactants, many acid groups like amino acids, etc, etc) will naturally move to lower free-energy states, and all the freed up energy turns into thermal. So, entropy is alright, because the thing radiates heat and heat’s nice and disordered. Free-energy gets reduced, so that works out as well. The heat gets radiated out of the local system as heat always does, meaning the system loses overall energy… and then, sunlight flows back into the system, completing the loop, and getting energy back in, so a nice loop is completed, except now things are in a well-ordered structure.

So, no, it doesn’t need to be a fridge to self-order itself. Simple chemicals will do it too, as long as they’re asymmetric enough that ‘big clump’ isn’t the lowest energy state.

Shelley,

“”left on their own in any kind of random setup, they’ll naturally move in towards eachother, heads touching heads, and tails touching tails.”"

Chemical bonds (of essentially any type) will only form in the proper thermal conditions; excessively high thermal entropy will provide too much kinetic energy for the chemical bonds to settle.

Ice is another good example of self-formed order. You just have to remove enough thermal entropy from the system to allow the polarity of the water molecules to align themselves geometrically – which is why we generally use refrigerators and freezers if we want to produce large quantities of it in a thermally excited environment (like a house in LA).

“”So, no, it doesn’t need to be a fridge to self-order itself.”"

Of course not. Every single time thermal energy is transferred from a hot body (with specific chemical properties, like polarity, etc) to a cold body, there is the potential for a low-energy low-complexity state of order to arise. (the reason fridges are still different is because the fridge does not merely cool down to the point of thermal equilibrium with the ambient molecules in your kitchen – this may still be an aside from our discussion though).

The point of the AIG article is that adding energy to a system does not simply produce biocomplexity. As you have pointed out, when thermal fluctuations occur and one body does reach low temperatures, there is the possibility for repetitious order to arise. When the temperature gets high, randomization occurs.

At either end, we still have no complex specified information, and thus no life.

Matthew:

If i’m following you right, then we both agree that low-entropy states are plenty possible in simple chemical situations (since the earth can pour out thermal energy into space, and take in new energy from the sun, it does get energy flow and so on)

That’s good to know, I think I’ve been miunderstanding the “Second law doesn’t allow order” argument being made. I think you’re arguing it’s the creation of new information that’s key, not *just* low-entropy situations, which may not have the needed complexity. In that much I agree. Sure, low-entropy is a necessary condition, but not a suffiencent condition for proto-life to arise.

(If I’m mis-stating your point there, by the way, please correct me. I’m just trying to rephrase it to make sure I know what you’re saying)

“”Every single time thermal energy is transferred from a hot body (with specific chemical properties, like polarity, etc) to a cold body, there is the potential for a low-energy low-complexity state of order to arise. “”

I think this is our key disagreement. “Low-energy” does not by any means imply “low-complexity”. Many low-energy states that chemical bodies can reach are surprisingly complex, varied, non-uniform, and non-regular in their ‘order’. I freely admit that virtually all of those complex states just contain meaningless, random information, can’t replicate themselves, and just sit there with their nice complex arrangement. It would be intellectually dishonest to say pretty much any of those resemble life in the slightest.

But all it takes is one single arrangement, one original proto-life molecule that ‘reproduces’ itself by, say, incorperating free-floating materials into its overall pattern, budding off self-similar copies of its overall structure that then break off. If its structure is robust, with small changes improving or hurting this proporty of picking up free materials, then it all becomes the natural selection game, and we’ve got the birth of biology.

Would it be hugely improbable that in a given reaction, such a molecule would arrive by chance from among all the possible complex arrangements that chemistry will be creating? Sure. But it by no means breaks thermodynamic laws, it’s possible by physical law. And there’s a *lot* of places and materials on a young planet where chemistry will be creating complicated chemicals, and there’s a *lot* of planets in the universe. I’m pretty happy trusting the anthropic principle there, once I believe that such chemical reactions don’t break physical law.

On rereading the article and the last post, I realize it’s more concerned with Evolution and how it operates once life has already gotten started. It’s not a “how did life start?” question, so much as “How does life add new functions onto what it already has?” question. Which means my above reply is kinda off point, I apologize.

I’m not much of a biologist, so I can’t fight that fight very well. Thermodynamics? Sure, I know it. Evolution? Eh, only in the vague sense of a person who’s never really devoted academic effort towards it. So all I can really say is “I’m not sure it’s obvious that the second law of thermodynamics applies in direct ways to the information theory of biological diversification.”

The problem with this subject is that it is so extensive; it needs a book to just explain the basics.

The creationist argument usually takes the form of: (1) a special theory – abiogenesis is impossible; or (2) a general theory – everything from the big bang to human evolution is impossible. The latter theory (which seems to be the original one) thus requires a good understanding of general science before you can begin.

Thermodynamics is also a very extensive subject and the second law of thermodynamics certainly has a very wide range of applicability. Quantitatively, thermodynamics frequently becomes very difficult mathematically and the second law is actually quantitative even if that fact is concealed within a verbal definition.

The basis of thermodynamics was laid in the 19th century and this is now know as classical thermodynamics and is a perfectly respectable subject even today and is much used in engineering. Classical thermodynamics assumes no detailed knowledge of atoms and molecules and, in the days that the second law was developed, such concepts were still extremely hazy. The 20th century saw the development of atomic theory and, in particular, quantum mechanics. This revolutionised the understanding of thermodynamics, though this understanding has been slow to filter through the education system. Thus the 19th century description of entropy as ‘disorder’ has hung on through the 20th century.

The term ‘entropy’ has a perfectly clear and exact meaning in thermodynamics and entropy, in this sense, is the word used in the second law. Unfortunately the word is also used in statistical mechanics and in information theory. To make matters worse, these topics are also relevant to the study of thermodynamics and of genetics. Entropy is also a word that has entered popular usage to describe disorder in the general sense. Entropy also has a reputation as being a word that nobody understands.

Thus a creationist, by taking selected factoids from classical thermodynamics, bio-chemistry, genetics, information theory along with a few erroneous assumptions and misunderstandings can come up with either the general theory or the special theory. The problem is that most replies are made by people whose knowledge of thermodynamics is a combination of what the creationist has told them combined with a half-forgotten recollection of something they were taught long ago.

In general, the creationist argument, as it has been developed over the last half-century, starts with the second law of thermodynamics, or the ‘law of entropy’ as they prefer; but it soon moves away into fields less susceptible to accurate analysis. Professor McIntosh of course knows plenty about thermodynamics and knows that other experts are weighing his every word. Just look how adroitly he leaps from the second law, kicking Professor Richard Dawkins argument aside en-route, to dive into a re-iteration of the old arguments of Henry Morris et al. Very clever, and no doubt very convincing if you cannot see how it’s done. The baby went out with the bath water as he went from energy no longer available for useful work to the absence of machines to make use of it.

Of course, if you want to understand the arguments, you need to learn about thermodynamics: Google for 2nd law. You may find this a disappointing exercice because the creationists’ argument only makes sense if you do not understand thermodynamics.