Why Evolution is science

Evolution provides a mechanism for describing how the world got to be the way it is today. This allows evolution to explain phenomena in our world. Why do some species look more alike than others? Evolution claims that they are related phylogenetically. Creationism, as far as I know, makes no attempt to explain this basic trend, and many others. Why did God make creatures that look alike, or better yet, make creatures that have large amounts of DNA in common?This is the defining feature of a scientific theory- employing a mechanism for explanation of data. Creationism is mostly composed of arguments against evolution- irreducible complexity, etc. Yet these arguments are simply against ToE, not arguments for another scientific theory. Saying that "God made it" is not an explanation, please explain where, when, and how did he make it? Why did his act of creation lead to cerain trends, like the inter-relatedness of species? Evolution simply cannot scientifically be replaced by Creationism until Creationism has a theory which can explain the why the world is as it is today.On further point about the displacement of scientific theories- in many cases, a new scientific theory does not completely throw out an old one. For example, General Relativity did not throw out Newtonian physics. Rather, a major point that lead to the acceptance of general relativity was its confirmation of Newtonian laws for slow-moving objects in a fixed reference frame. In other words, the new theory was only accepted after it proved the old theory to be true in the cases that we commonly use the old theory for. This is not always the case, but describes many of the "revisions" to science in the last 200 years.

Having proposed this topic and then dissappeared for a few days, I feel like I should say something.

quote:

---

I suppose the reason the question of "Why evolution is science" was raised is as a response to the assertion that evolution is religion.

---

This thread was raised for two reasons. First, perhaps the thread should have been called Why Creation is Not Science, since that was more the intent of the initial post. Second, everyone seems to have their own opinion of what makes science science, and I thought it would be nice to try to reach some kind of consensus on this issue. If you had to give a one or two-liner describing what makes an idea or theory scientific, what would that be?

quote:

---

And it's interesting to note that one of the problems with Darwin's original theory was that it lacked a mechanism for passing individual characteristics on to descendants.

---

Yes this interesting. I would actually not refers to Darwin's writings as the theory of evolution, and make a specific effort not to do so in the original post. Darwin made a series of convincing scientific observations that pointed to the idea that a mechanism should exist. Evoloution as it appears today is a full-fledged scientific theory because of the inclusion of a mechanism.Is this description lacking anything?

Confidence,Welcome to the mix. I agree with RazD, you need to tell us what you mean by the difference is between evolution and natural selection to you. It seems like evolution means speciation or macroevolution, or something. Actually, I don't think it would be a bad idea for you to start a new post where you articulate your evolutionary views.Also:

quote:

---

But evolution predicts mutations that gain information

---

I'm not quite sure what is meant by evolution or by information, but if you were to more clearly define these terms, I'm sure myself or others here could either find a problem with your definition, or suitable evolutionary examples that fit into your definition.

Confidence-A few questions, which are sort of unrelated, but ones I would like to know your answer to. How old is the earth? Is Archaeopteryx a bird or a dinosaur? I'm assuming your claims are along the lines of god creating the archtypes of each taxonomic group, after which each taxanomic group underwent natural selection into separate species. Where do you draw the line? Did god create an archetypical canine, or an archetypical carnivora, or an archetypical mammalia? This is important to know, since we must know what group to start with from which no new functions are added.Also, it would be nice if you could define what you mean by information. DNA is a code- but it produces proteins, which have a physical shape and function. When you talk about adding information, do you mean adding new proteins to a system? Because this is a rather strange way of defining information, and because if this is how you define information, then we have proof that information is added- or new proteins are present- in recently evolved species.Your theory of natural selection and evolution is fine in my mind. It is not evolutionary theory as most biologists think of it. The idea of good and bad mutations is foreign; in the conventional theory, mutations either benefit an organisms survival and are selected for, or they do not. But if we were able to find "good" mutations, under your definition, then I think it is safe to say that your theory is flawed.To recap what examples need to be shown to prove your theory false:

quote:

---

Good mutations are mutations that eventually lead to a new function.

---

quote:

---

The problem is that no mutation, or line of mutations, have confirmed the 'good' one.

---

My favorite example, to make this case, will be Chrysopelea, the genus of flying snakes. http://www.flyingsnake.org/ These are snakes that glide through the air through modifying their body. Their ribcage is flexible, and is pulled outward through specialized muscles, which increases their surface area and gives them a more aerodynamic shape. All of the species in this genus can parachute, though a few are actually able to glide ( a minor distinction that refers to their equilibrium glide angle being >45 degrees; in both parachuting and gliding, lift is still being produced). All the species can move across the ground and up trees just as well as other snakes. In other words, their increased flexibility comes with no loss of functionality, only additional functionality. The same can be said of flying squirrels, and bats. Of course you could claim that bats (and flying squirrels) were their own archetype, and that the sister group of lemurs and flying lemurs have their own archetypes. But it is pretty hard to make that claim about flying snakes. You wouldn't be able to tell the difference between a flying snake a regular snake until you threw them out of a tower, at which point one falls haphazardly and the other locomotes quite far away (this has been done). Therefore, starting with an archetypical snake, you find one with a new function, or a "good" mutation.There are other examples I can give, but I will also keep this post short.

To get back to the topic, I want to give Confidence some credit. What he/she has outlined is in fact a scientific theory, unlike a lot of what has come up on these forums. Confidence is in fact arguing that current evolutionary theory is wrong, and that his/her theory is correct. What will hereby be refered to as Confidence Theory, CT, is this- the mutations that lead to a new function never occurs: the only mutations are ones that infer a loss of information/function. This implies that all forms were present since the beginning of time (6000 Years Ago), since no new forms with new information could be created. Feel free to correct me if I am mistaken.Now to address CT directly.
Species have evolved new functions with new information. I gave a clear cut example of this- flying snakes. Your response was simply that the information to encode this new function was present from the beginning of time, it was simply switched on or off( expanding your argument about wings). This is quite a copout answer. What's to say that god didn't create only one original species, with genes to code for every possible variation that has arisen in life and a whole hell of a lot of switches? You've created a theory that can always defend against legitimate examples of "good" mutations by adding in a dormant gene and a switch. Is this really the theory you want? Because if we really push this issue, you are going to have to argue for a hell of a lot of dormant genes and switches.As a separate point, in 6000 years, there is not enough time for the flying snakes to speciate from the other snakes, meanign that flying snakes had to be created as a new archetype since the beginning of time. Yet flying snakes are very similar to other snakes. Which leaves you the problem of answering the question in the original post:

quote:

---

Why do some species look more alike than others? Evolution claims that they are related phylogenetically. Creationism, as far as I know, makes no attempt to explain this basic trend, and many others. Why did God make creatures that look alike, or better yet, make creatures that have large amounts of DNA in common?

---

A note to everyone else- the example with wings is not enough to prove CT wrong. That example simply shows that information is not neccessarily always lost in mutation events, which is compatible with
CT. We need a mutation that brings about new functions.

I think RAZD has excellently talked about your view of information, I just want to add one thing I think you should be careful of-On one hand you talk about information being defined on a macro level-

quote:

---

But it did not have the information of a hand, or a horn, or even bone itself. So it is safe to say that we as humans have more information in our DNA than the DNA of that single cell.

---

On the other hand, you talk about how information is generated and replaced on a genetic level-

quote:

---

I'm sure we could measure the difference based on how many four letter chains there are in DNA. This would, in effect, be measuring information relative to different DNA.

---

This is in effect two different quantitative descriptions of information. There is not yet a known mechanism by which a "hand" or "backbone" is added to an organism, or by which macro-information is increased. But on the other hand, there are known mechanisms that can increase DNA length, thus showing an increase in genetic information.From what I understand, the problem with information arguments is this. Creationist see the problem with macro-information, and from that develop a theory of decrease in information. This theory of information needs to be defined quantitatively to be scientific, so naturally they revert to quantifying information in the genome. Yet there is no genome description of information yet postulated which cannot be shown to increase by known mechanisms. Therefore ceationists are in a pickle.RAZD has pointed out the problems with a macro definition of information. Here is an old thread that discusses the issues of genetic information, though I think my concise summary given above describes this previous thread pretty well. Please consider these two distinctions in information type when formulating a definition.And you still have not responded to a question raised in the opening post. Under your theory, how do you explain species that are similar and seem to be phylogenetically related? To pursue that snake example, you are claiming that snakes and flying snakes are two different groups created at the beginning of time.

quote:

---

Therefore, flying snakes were there at the beginning.

---

Why do snakes and flying snakes have such similar physiology if they were distinct groups created at the beginning of time? If god could creat flying snakes however he wanted, why are they like other snakes? There are many other better ways to achieve gliding than flying snakes, why was the snake body plan used to create this set of gliders? These basic questions are easily answered in conventional evolutionary theory, but pose major problems for your creationist theory.

Since we seem to be moving to the genetic level, I'm going to push this one step further. The Linnean classification system groups all organisms by similarities. I'm guessing there wasn't one Reptile created at the beginning of time, there was probably something more like a snake, a lizard, a turtle, and a crocodile, at the very least (we'll forget dinosaurs and birds for the momment). Why are these four independantly created groups similar on both a physiological AND genetic level? Why is the lizard genome closer to a turtle genome than a kangaroo genome, if the lizard, turtle, and kangaroo are all independant creations?Also, if there is only one snake kind, how did flying snakes come about? The flexible ribcage must have been present someone in the genome since the beginning of time. Was there a switch that turned on flexible ribcages at some point in evolutionary history?

Is this a response to my question? Because if it is, you should really drop the technical jumbo and make the point you are making more clear. The chapter included talks about mutations formed by speciation- I don't see the relevance. Are you saying that snakes should appear to be genetically closer to kangaroos than to turtles because of evolution rates after speciation? I'm sorry if I chose bad sample organisms, but my initial point still stands.

At this point- although I agree that there are still some problem's with confidence's definition of information- I think we should drop the arguments about the definition of information for a second. Observe this statement by Confidence:

quote:

---

However, this piece of code remains in the DNA,(it is not considered information) and during the next generations, more and more mutations change the overall semantics of this code, and now after Z many generations this piece of code now codes for a different protein. It has the same length as the previous code for making the original protein. Now the amount of information is the same as before the first mutation. But information has been gained (first lost, then gained).

​

It is this type of information gaining that I, and other creationists, believe NEVER happened in life.

---

Unlike a lot of what I observed here, he has developed a scientifically plausible theory that is making testable predictions. Those predictions just happen to be false. This sort of information gaining does happen. Now, I am not a molecular biologist, so I am in no position to describe and defend the sort of examples Confidence is looking for. RAZD has outlined a few, perhaps some people knowledgeable in evolutionary genetics can point to a few others. This is all that needs to be done.These sort of comments are not helpful (by RAZD):

quote:

---

Notice that evolution only needs the information to be changed for a mutation to make a difference in the organism, and doesn't care whether it is "more" or "less" by some arbitrary metric. Evolution can easily go from (1) to (2) OR from (2) to (1) and it doesn't matter

---

This is what evolutionary theory says- it makes no distinction between information gain and loss in evolutionary changes. Or by implication, it claims that both types of change should occur. I believe Confidence is aware of this claim, and he is in fact challenging it by claiming that only information loss is possible. What is needed is not a further description of the claims of evolutionary theory, but rather examples showing that information gain is possible, or that what evolutionary theory says is true.Just trying to bring peace and understanding---

RAZD,Yes, I agree with all you are saying. In fact, I think we are saying the same thing now that yoou have elaborated on that quote.Hello Brad, nice to meet you.

This post is just to add an example I have found, to the list of examples all ready provided by RAZDWe catch many fish with nets, and when we do so we provide a strong selective pressure on the fish- something like 90% are caught. The ones that survive are the ones that slip through the net, typically ones that are small in size. The problem is that small fish are typically juveniles, or not yet reproductive. The genes that get selected for are often one's that accelerate growth and reproduction, so that an individual grows and maures very quickly, releasing some eggs before being caught. A different strategy is employed by pink salmon. These fish have actually slowed growth rates, so that their sizes at any one point in time is smaller. They also reach smaller adult sizes, so that for a good portion of their lives they are still able to slip through nets and reproduce.
Evolution: Library: Shrinking SalmonTwo entirely different strategies are employed here, one accelerated growth, one slowed growth. I think that creationists tend to jump to conclusions in proclaiming that an adaptation must be a loss of information. Now, I'm not sure whether an accelerated growth rate confers a loss of information, but it seems logical that both an accelerated and decelerated growth rate cannot both confer a loss of information being opposite trends.

I don't think its fair to ask Confidence for proof that flying snakes were the first kind- he is making the best explanation he can given the information he has been told. This is similar to evolutionary stories that we come up with to show how it is possible for a certain feature to evolve, though it is not known exactly how it evolved.It is interesting to point out, though, that flying snakes could not possibly have have been the original species, because most other snakes have rigid backbones. These snakes gain rigidity in their backbone, which is obviously an increase in information. Am I playing the devil's advocate? I sure am. Anything can be argued to be an increase, or descrease, in information if you are cunning enough. I think we need a more precise definition, and need to respect the difference between macro-information and genetic information. Confidence, please tell us which of these two types of information apply to your definition, and maye some real-world examples of information loss would be nice also to help clarify the definition.On a more serious note, other snakes have evolved features flying snakes do not have, such as venomous fangs, hingable jaws, and (oddly enough) accessory forelimbs. Snake Evolution - Photos of Vestigial Hind Limbs on Snakes These all seem to be increases in information- are they caused by switches? Are there two original snake kinds? This theory is getting awfully confusing to define, much less defend, perhaps a simpler one describes the situation better.

quote:

---

Why throw a good mechanism of survival out the door when it will work for other kinds?

---

Explain vestigial body parts. Let's stick with the most well-known as an example. Why do human's waste energy building an appendix, if they do not need it? Sure, god may have used a similar body plan to create chimps and humans, but are you suggesting that he didn't have enough foresight and knowledge to remove the unneccessary parts from the chimp blueprint before modeling humans from it? Or if the human blueprint was made first, why was the appendix included at all? In fact, vestigial organs are a pretty good case for unintelligent design- if things were designed from scratch, there are a lot of better ways that major physiological systems could have been designed. Yet they were not designed that way, because the physiology of new organisms had to build upon those systems of ancestral organisms.Still awaiting a response to the information-gain examples offered by RAZD...