This could be extremely broad, but it's an attempt to redirect the ongoing discussion with Kelly from the "I'm not an Atheist!" thread where the discussion is extremely interesting but also wholly off-topic.
I'm going to try to constrain this to a discussion on whether "Creation Science" and "evolution" are actually science. Kelly has claimed that "Creation Science" is in fact scientific, while disparaging evolution as unobservable and unscientific.
Let's start with some definitions:
Science
As it applies to this discussion, the term
science refers to any branch of study that follows the scientific method. The scientific method involves making a set of observations, creating a hypothesis explaining those observations, making predictions (or logical deductions) from the hypothesis, and then testing those predictions through experiments or the collection of additional evidence. This is followed by modifying or discarding the hypothesis based on new evidence.
This means that unfalsifiable hypotheses are not part of the scientific method - all hypotheses must be testible, and therefore falsifiable if a certain set of conditions are true.
This also means that pre-conceived conclusions are not scientific. Science examines the evidence and draws conclusions objectively and with the express purpose of minimizing or eliminating personal bias from any sort of "world view." This is why the scientific method involves rigorous testing as well as the peer review process - theoretical frameworks are judged on the accuracy of their predictions, not based on how they fit in a pre-defined "world view."
Evolution
Evolution, simply stated, is change over time. The Theory of Evolution explains the variety of life observed on Earth through the mechanisms of mutation guided by natural selection and genetic drift. Small mutations in each generation are made more or less prevalent in a population due to natural selection, causing the population to change as a whole in response to new selective pressures. When populations are divided geographically, the generational changes occur independantly and in response to different slective pressures, eventually resulting in new species (and in the broader sense and over longer timescales, new families, phyla, genara, etc).
The Theory of Evolution has nothing to do with the origin of life itself - evolution is the process of change in populations of already-existing lifeforms over multiple generations, and so cannot possibly apply to the origin of life.
The Theory of Evolution does not have anything to do with "morphing," where one species "turns into" another. Evolution occurs to populations, not individuals, and over multiple generations. This is not Pokemon.
The Theory of Evolution
does predict that
all features should not be unique, but should rather be slightly modified versions of already-existing features from other species. This can and does result in additional or less complexity, where redundant systems can evolve in an organism and then change in function compeltely or establish an alternate method for the same purpose. So-called "irreducibly complex" systems are the result of re-purposed features or systems in which redundant steps have been added and part of the original chain removed.
Creation Science
Creation Science, or
Creationism, is the process of attempting to prove a literal interpretation of Creation as described in Genesis, where living things do not evolve but are rather Created, whole, as a divine miracle.
Is Evolution science?
Science requires that we make observations, establish a hypothesis, make predictions from the hypothesis, test those predictions, and modify, keep, or discard the hypothesis based on teh results.
The Theory of Evolution began with the observation that various features of populations of birds changed over generations - beaks would become longer or shorter over a few generations, for example. A hypothesis was made: changes in given populations are guided by natural selection. This predicts that, to use the bird example, beak length should be guided by the food source available, where certain food sources favor longer beaks and others favor shorter beaks. This hypothesis was borne out via direct observation - on islands where the same species resided, beak lengths were directly correlated to food source.
So far, this meets the requirements of the scientific method. But the Theory of Evolution has...
evolved...since Darwin's day.
We now have an understanding of genetics and the fossil record, as well as a greater understanding of the form and functions of features in extant living organisms. This has added a tremendous amount of data to be examined to test the predictions of the Theory of Evolution.
Evolution predicts that all life on Earth should be related to one or more (but msot likely one) distant ancestor species. We should see less variety in life forms the farther back we look. This is borne out in the fossil record. Evolution predicts that closely related species should be similar also on teh genetic level. This was also verified, but genetics also gives us various markers (typically in the form of genetic damage from viral infections and mitochondrial DNA) that can show us exaxtly when various species branched apart and had their final common ancestor. Further, genetics showed us the specific method by which traits are inherited, and showed us how "information" can be changed, added, or subtracted in each generation - the specific mechanisms behind mutation. In this case, not only was the prediction verified, we obtained
more evidence than we expected in support of evolution - in fact, evidence that doesn't make any sense
without evolution.
These are just a few examples. But as you can see, the Theory of Evolution is a well-tested theoretical framework that adheres to the scientific method - it
is science.
Is Creation Science...science?
Creation Science begins with a literal reading of Genesis - species are specially Created, and do not rise from pre-existing species. It then proceeds to take observations in support of this "hypothesis" - dogs cannot give birth to cats, and each species is its own "kind."
But has this hypothesis been tested? Given that scientists have
directly observed the formation of new species both in the lab and in the wild, the Creation hypothesis should have been at the least modified, if not outright discarded.
Creation Science does not begin with observations, it begins with a conclusion. It then seeks to "interpret" evidence in support of the pre-established conclusion. Contradictory evidence is ignored, or "re-interpreted" to support the conclusion anyway. Instead of modifying the hypothesis based on new information, the "interpretation" of non-supporting evidence is modified.
Clearly, this is not in line with the scientific method. This is apologetics - a form of rationalization used to justify a belief in the face of contradictory evidence.
It would seem that while the Theory of Evolution is valid science, "Creation Science" is not scientific
at all.
But now let's go over some of Kelly's specific claims in the previous thread, since they detail some of the claims of Creation "Science":
1. A trait will alter because of a stimulus. 2. The trait will return to the norm if left to nature or returned to its original conditions. 3. No new information is added to the DNA.
Traits do nto alter due to stimulus. Traits alter randomly - mutation obeys the constraints of chemistry, but is otherwise nothing more than the result of copying errors in the DNA replication process.
The
spread of the trait throughout the population is dictated by the stimulus - the selective pressure. Irrelevant changes will go mostly unnoticed; mutations that give a benefit in a given environment will tend to be more common in each generation as the more successful individuals out-reproduce their cousins; mutations that are detrimental in a given environment will tend to die out. Whether a given trait is positive, negative, or neutral is dictated by the environment - the amount of competition, the source and availablitiy of food, temperature, etc. When the environment changes, the traits expressed in a population tend to adapt over several generations as those with beneficial small changes outcompete those without such changes.
But the most egregious error in Kelly's claim is that "no new information is added to the DNA."
This is
false.
Mutations are copy errors in the DNA replication process. DNA is comprised of four basic interchangeable building blocks - abbreviated with A, T, G, and C. Let's say we have a small part of a DNA molecule:
TGCCTAGC
When this 8-letter gentic "word" is transcribed, a mutation may occur. The offspring of this organism could have any of the following "words" instead:
TGCCTAGCC
TGCCTAG
TGCGCTAGC
TGCATAGC
Mutations can result in teh
addition, subtraction, or simple change of genetic information from one generation to the next. They are also extremely common - it is estimated that human beings each posess several hundred small mutations, genetic information that was not inherited from their parents and is instead the result of copying errors during reproduction.
We can observe direct evidence of this in the lab, and in fact it's the cause of the so-called "superbugs" that occasionally go around the news outlets.
Bacteria reproduce asexually - they simply divide. Each is a clone of its parent. Without new genetic information, no new traits could ever evolve.
And yet something curious happens in an experiment replicated frequently around the world:
Begin with a single bacterium - one cell. Allow it to reproduce in a petri dish until a sizeable colony is established. All of the organisms should now be descendants of the original bacterium.
Now introduce a selective pressure - an antibiotic.
The vast majority of the popualtion will die - but invariably some will remain. These few will thrive in the petri dish where they simply survived before; with less competition, the antibiotic-resistant trait will flourish and become nearly universal.
Where did this resistance come from? If each individual is a clone of its parent, how did this new trait arise?
The answer is simple: a copying error during replication resulted in a slight change that, while irrelevant at first, became a positive adaptation when the enviroment changed with new selective pressures.
Obviously, new "information"
can be and is added to DNA all the time. Kelly's claim is directly refuted by commonly-observed evidence and the simple mechanisms by which genetic replication work.
The argument for evolution is that species will change slightly over time and eventually change into something completely different and will over eons of time eventually become a new species. This theory was thought up as a hypothesis and as science advances, the facts have not been found to support it, but much has been provided to dispute it. There are no examples in nature that even remotely indicates a change of species through evolution.
Curiously, this is not what
any biologist will tell you. Neither will any paleontologist or geneticist or zoologist agree with your claims regarding their particular fields of study.
As I said to you in the other thread, we have
directly observed new species arising from populations of previously existing species. We have seen it both in nature and in the laboratory.
Direct observation contradicts your claim that nature provides no examples of species changing through evolution. You cannot get a more clear falsification than that, Kelly.
The fossil records have zero transitional forms. Even fossilized insects such as spiders and ants that have been dated to pre-historic times are identical to modern day spiders and ants.
Examples of transitional fossils abound in the fossil record. Would you like to see some?
Here are just a few of the transitional species relating to hominids - us.
Here are some transitional fossils relating to the evolution of jawbones.
There are more - many more. Technically, every species is transitional, existing partway between its ancestor species and its descendant species. But even those examples you're looking for, where we see the direct transition from one type of organism to another (single-celled to mutlicellular, invertibrate to vertibrate, dinosaur to bird) are
plentiful. All you need to do is
look. The resources are available online - I found the above images in moments.
There are three critical flaws in the theory of evolution through gradual change: Dysfunctional change,
Many changes are dysfunctional; occasionally a dysfunctional change can become a beneficial one when the environment provides a new set of selective pressures.
the DNA code barrier, and natural selection removes DNA information but does not add new information.
False, as detailed above. DNA can be added to, subtracted from, or simply change in any given mutation, allowing for a net increase in diversity over time - which is exactly what we see in nature.
Conclusion
It would seem, Kelly, that your claims stem from ignorance and reliance on sources whose claims are outright
falsehoods. Creation "Science" is no such thing, and the Theory of Evolution
is a valid branch of scientific study.
"Is it science?" please. I understand that this is extremely long and broad, but the Kelly debate needs to have its own thread, and I think Kelly's claims deserve being addressed.
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