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Now, here is the first problem. You are stating things as though it is supposed to be obvious what you are talking about. I have seen at least six solid definitions of Macroevolution in the past. I don't know what you mean by it at all.

Whats more, the fact that you think that the laws of thermodynamics have anything to do with evolution shows that there is something wrong with your understanding of them.

So, before I write my essay and explain, would you do me the curtasy of explaining what I have to work with? Could you please do me two things;

1) Define macroevolution. While you are at it, give me your definition of the simple term evolution in a biological context.

2) State, to the best of your ability, the laws of thermodynamics.

OK. Lets take this challenge now.

That is a middle level definition of macro-evolution, post litteral creationism (which says speciation), past inteligent litteral creationism (which says change of kind). It is the level of metaphorical young earth creationism. Actualy, that level a few years ago. See, the metaphorical YEC crowd say that anything that hasn't been observed can't be used in the theory, so untill enough papers were published, they used information increase as something that hasn't been seen. It has.

However, we have a few questions to confront here. Firstly, what do we mean by information.

When we are talking about information in the biological sense, we are normaly talking about genetic information encoded on the animals DNA. In order to understand what this means, we need to take an in depth look at how the genome itself works.

First, you need to know a lot about genetics. Fortunately this is all simple, and should have been covered by most high or secondary level biology classes. For the benifit of the younger or those who have forgotten;

There are two words I will be using a lot. Gene and allele. The meaning depends on what kind of biologist you are, or what books you read.

If you are a genetics expert, or work in molecular biology, an allele is a certain form of a certain gene. An allele sits in a certain position in the genome, that position being refered to as the gene. So someones gene-so-and-so (interesting fact; genes are normaly named for what happens if they are switched off or go wrong) will have a particular allele sitting in that position and being read. Actualy, you have two alleles in each genetic position, one from each parent, on each version of each chromosome, and so the whole thing about dominent and regressive alleles comes into play.

Of course, if you are a fan of the evolutionary biologists and Richard Dawkins, you can simply use the word gene to describe an allele, as the functions of each are identical. When you have a certain allele, that becomes your gene for so-and-so. That helps cut out a lot of confusion and jargon.

A gene, or allele is simply a section of DNA. DNA is a long molecule, made up of a string of four different nucleotides, or a certain type of chemical capable of certain bonds. We will simply use the abreviations, A, U (or sometimes T), G and C, as the actual chemicals are not important. These chemicals can be seen as 'letters' in the genetic code.

You can look at DNA as a long string of these chemicals. Each three chemicals is a 'word', giving a certain instruction to your body. This instruction is either to code for a certain amino acid, or to stop coding amino acids. When your DNA is 'read' by a cell, the amino acids that are coded for are joined together into proteins according to the code in the DNA. Each gene you have codes for a certain protein. What proteins are present in your body dictate how your body works, sometimes in a general way, sometimes very specificaly.

In summary;

A gene is a section of DNA.
It is a string of 'letters', each making up three lettered 'words', which code for amino acids.
A string of words forms a gene, which is a code for a particular protein.
Proteins control how your body works.

Most of the mutations that happen in your body are simply a few letters misscopied when your DNA replicates itself. There are safeguards in cells to stop this, but they can't stop everything.

The list of three lettered words, and their coded results are best shown in a chart;

Now, notice that there is a lot of redundancy. That is, a change in the third letter will probably not change the acid coded for. However, there are some serious vulnerabilities in the code. Notice the few acids with '(initiator)' by their name. These are the ones that tell the cell to start coding for a protein. Similarly, the ones with 'terminator' act as full stops, ending the coding. If one of these words changes into another acid, it can simply stop a whole gene from working, turning it off and stopping the coding for that particular protein.

Very minor changes on this level can change a whole genes workings.

Whats more, a single change to a single amino acid can drasticaly alter the workings of a protein. While they are often strings of hundreds of amino acids, a single acid change can alter the way the a protein arranges itself (look up protein folding), and so the way it works within the body.

To put it simply, a tiny change in the most minor part of your DNA can effect your body in unpredicatable ways.

Whats more, a change that creates a protein that, say, changes the format of your hair to make it lighter/darker can be passed on, becoming protected by the very safeguards that it beat to be created, and become a common genetic allele being passed on in the population.

So new genetic alleles can be created, and it is probably more sensible to look on each allele as a range of genes that code for the same thing, amost like a population of animals (more accurate would be bacteria or another asexual species) where all the results are more or less the same, but the exact makeups are somewhat different.

The types of mutation that can arrise are quite obvious when you think about it. You can have a simple copying error that swaps one letter for another or an insertion or deletion of one or more letter. However, these are the only forms when you look at the letter structure. On a wider scale, the copying mechanisms, and the whole structure of the cell, focuses more on the genes as a whole, or even on whole batteries of genes. Such mistakes can be made on a genetic level, with whole 'words' being copied into the wrong place, or repeated, or lost. Such changes could well be refered to as macromutations, as they tend to have an instant and noticable change on the genotype and phenotype (the body of the animal/plant).

On a genetic level, the amount of information is almost arbitary. Letters and words can move about or be swapped about, and minor changes can cause huge changes on the level of information.

Whats more, because of the way genes are read, larger scale apparent changes, such as order or grouping changes can happen on a chromosome level, with relatively small alterations on a genotype level. Hence why chimps and us are so similar, despite them having an extra pair of chromosomes.

I have deliberately steered well clear of 'information theory' so beloved of ID advocates, because it is simply too mathematic for me to have grasped fully just yet, and has even less relevance to this subject than thermodynamics.

Which I am about to launch into an essay on, after I take a rest from typing.

Sorry for the slight page stretch there, but better than the alternative I am afraid.

Oh, and I just want to cite this commonly used source;


Theobald, Douglas L. "29+ Evidences for Macroevolution: The Scientific Case for Common Descent." The Talk.Origins Archive. Vers. 2.83. 2004. 12 Jan, 2004 < http://www.talkorigins.org/faqs/comdesc/ >

Now then, this one is going to be somewhat longer than it maybe would be expected to be, but I want it to be fearly conclusive, and it is kinda in my area of study.

There are four basic laws of thermodynamics. Few people know many other than the first and second although the zeroth law is normaly taken as common sense. Here are the basic definitions;We shall take these laws a priory. Assume they are true. The Zeroth has no effect on the questions here. The first is bunk, and I will go into that soon. The second is hard to understand, and will take up the majority of the writings here. The third is again not needed here, so we will ignore it unless you are interested.

Now for the first law of thermodynamics.

This is a classical law of physics. A direct mathematical discription of the conservation of energy. Here it is in its simplest physical form;

Note, chemists swap the - sign for a + and say it is work done on the system rather than by it. Doesn't make any real difference. The expression means the same thing.

In words, the total energy change in a system is the sum of the changes in all the forms of energy within that system. In this case, thermal energy and mechanical energy (work).

Now, for a closed system, the total work done, and the total thermal energy change, and thus the total energy change, must be zero. So, if yo could define a closed system, there would be zero energy change within it unless work was done on or by it, and it was therefor no longer closed.

However, the law is bunk.

Conservation of energy is today the conservation of mass energy. It has been shown (and give me three hours and a lot of equations, and I can prove it to anyone) that mass is simply another form of energy, with the ratio of E=mc^2, with E being a single unit of energy (Joule), m being a unit of mass (kilogram) and c being the speed of light (3x10^8 ms^-1).

So we have to add this into the equation as well. This gives us;

U = Q - W + mc^2

Oh, and this is assuming that the only forms of energy in a system are thermal and mass. There are also other forms of potential energy, such as electric, graviational, etc, which have to be factored in.

It also ignores quantum mechanics, but once I get into that I don't get offline till the sun rises.

Anyway. The second law.

From Hyperphysics, a source used by my university for undergraduate level physics;Emphasis mine. A law that happens to be a general principle. Lets see this waterfall analogy then.

Heh, this must be easy then. Well, not really. This is the simple part of the law. The more complex and recent aspect of the second law is the concept of entropy.

Entropy is something that next to no-one understands. It is a measure of multiplicity. From Hyperphysics again;In other words, it s a measure of the ways that a certain setup of a system could have come about. Something that had to have a certain sequence of events occur would have high entropy. Something that could have come about any number of ways, randomly in the conventional sense, would have a lower entropy. A nice graphical illustration from the same site;
Omega here is the multiplicity. The entropy is defined as the natural logarithm of this number, multiplied by the Boltzman constant. The reasons for this come from classical thermodynamics, and allow it to be used in precise equations.

Interestingly enough, this much is enough to explain the second law itself. The second law states that, as time goes on, the odds are that the multiplicity of a system will increase. This seems very obvious when you think about it (imagine a thousand highly ordered balloons in a room suddenly being disturbed by random air currents - they leave an ordered, structured, lot multiplicity structure and energy a high entropy one).

It is also from this idea that we get our concept of times arrow, but again, this is going too in depth for the moment.

Again, in a closed system, entropy will always increase. There is no way to decrease it without doing work on the system. Think of it as a new type of zeroth law, only for entropy rather than heat. If systems can come into contact, the entropy can be shared between them, rather than being local. However, unlike heat, it doesn't alway reach an equalibrium.

Entropy is a total for a system. The total connected system. The local entropy of any particular patch of that sytem doesn't really matter too much. A fluke of nature, a patch of low entropy, can be created assuming there is higher entropy elsewhere in that system. When dealing with a huge system, such as a beaker of chemicals in a lab, you can get a lot of such patches, and so complex chemicals can be formed if you encourage their existance.

The fact is that none of this argues against evolution in anyway. The very rational that would level it against evolution also levels it against life itself. Evolution relies upon the same basic biological processes that let you or me live, and nothing more. If you are still breathing, then evolution is also possible. But let us just look at why life is possible in the first place, just in case we are being animated by some unnatural force, eh?

We are entropy machines. Any living thing is a patch of extreme low energy that maintains itself by taking in low entropy material and outputting high entropy material. The original low entropy material is produced by plants, and then entered into the food chain. A decent explanation can be found here;
http://hyperphysics.phy-astr.gsu.edu/hbase/biology/tree.html#c1
We take in these ordered structures, and use processes involving mitrochondrea to transfer that order to other structures, such as the proteins that basicaly define our lifes.

Evolution doesn't involve anything you don't do every second of every day.