First of all, I would like to get something out of the way:
EVOLUTION IS A PROVEN SCIENTIFIC FACT.
EVOLUTION IS THE SKEPTIC’S GREAT FISH STORY.
How can both of these statements be true? It comes down to the chosen definition of the word “evolution.” If by evolution, one means the co-existent processes of natural selection (survival of the fittest) and environmentally produced variation within a species (microevolution), then there is prodigious evidence and experimentation that demonstrate its validity. Otherwise, then we are talking about a “fish story.” It is important to note at this point that I am not claiming that the Neo-Darwinist theory of biological evolution is impossible; I am claiming that there are serious threats to its credibility and probability. Just like any tale that seems too fantastic to be believed, there are details that simply do not add up. In addition, relatively simple math suggests the overwhelming improbability of the theory. This does not mean that it is definitely false, just unlikely.
Even though I am going to present a very abbreviated overview of my perspective, I want to start at the beginning of the tale. Here is how Carl Sagan described the origin of life (the results of abiogenesis):
In those early days, lightning and ultraviolet light from the Sun were breaking apart the simple hydrogen-rich molecules of the primitive atmosphere, the fragments spontaneously recombining into more and more complex molecules. The products of this early chemistry were dissolved in the oceans, forming a kind of organic soup of gradually increasing complexity, until one day, quite by accident, a molecule arose that was able to make crude copies of itself, using as building blocks other molecules in the soup.
…As time passed, more elaborate and more accurate self-replicating molecules arose. Those combinations best suited to further replication were favored by the sieve of natural selection.Those that copied better produced more copies. And the primitive oceanic broth gradually grew thin as it was consumed by and transformed into complex condensations of self-replicating organic molecules. Gradually, imperceptibly, life had begun.
Although this passage seems to give a very neat and orderly process for the initial rise of living matter, it essentially “yada-yada’s” the most important part: Sagan states simply that “a molecule arose,” without any insight into how this is possible. Although he mentions the “primordial soup” and lightning – two key factors in abiogenesis (or biopoeisis) – he demonstrates a key failure of all naturalistic theories of the origin of life: namely, how this first molecule was able to not only replicate, but produce copies that could also replicate. The fission of this original molecule, spurred by the vast energy boost from lightning, could theoretically occur, but would require yet another lightning boost to those same particular offspring in order to continue the cycle and allow for the evolution of the molecule into increasingly more complex molecules. While I am not a biochemist, I know enough about math and probability to understand that this is a highly unlikely series of events, even if it could possibly generate life (more on the math in a bit). Of course, this second part is a difficulty, as well. With the technology and access to immense amounts of power that is currently available to scientists, there has been no experiment that has been able to replicate even a tiny fraction of the steps necessary to produce life.
Of course, my theory is that “God said, ‘Let the waters abound with an abundance of living creatures, and let birds fly above the earth across the face of the firmament of the heavens.’” (Genesis 1:20) Although this is a very tidy explanation (especially combined with the rest of the Biblical creation myth), it is not particularly scientific, and may even be symbolic. The Bible certainly does not describe the actual process by which God created, nurtured and expanded life, and I think the science behind related theories is fascinating, although it is important to note that the Genesis account is not contrary to known science, either. Skeptics claim that belief in Biblical claims requires too much faith in unsubstantiated stories, and yet they cling to ideas that remain in contradiction to known science.
A good example of the flaws in “particles to people” evolution is the lack of legitimate intermediate forms, often known as “missing links.” In order for macroevolution to be true, then all current species must have evolved from a common ancestor. This process would require creatures that span the differences between, say, amphibious frogs and land-borne lizards. There is little (if any) clear evidence that such intermediate forms ever existed, and the viability (ability to survive) of such forms is against sound biology. Natural selection implies that variations in a specified “critter” that give it a survival advantage will be passed on to its descendants and, over time, collections of variations could possibly produce something quite unlike the original creature. This blind selection process cannot “choose” variations that produce no advantage, such as random extensions that may someday become a leg. Also, certain complex systems cannot have any effectiveness unless all of the parts are present and active, such as the eye. There would be no survival benefit to any individual parts, and therefore those characteristics would not be selected for heredity, at least by any blind natural process.
Evolutionists will claim that intermediate forms have been found in the fossil record, and give as an example Ambulocetus, a supposed land animal-to-whale intermediate. The following diagram shows the scientists’ reconstruction of a possible skeleton and an artist’s rendering of what Ambulocetus could look like when fully fleshed out. In the final picture, the yellow shaded area indicates what was actually found, and the white areas were added, to include the entire spine and the vast majority of the leg and shoulder. In addition, the bones in the hip and knee areas were found 5 meters above the rest of the fossil. If you picture the fossil without the white areas, then the reconstruction is not altogether dissimilar to creating constellations, just with a little more scientific reasoning.
Another example is Pakicetus, shown below. In the drawing on the right, the dotted sections of the skull indicate what was found. It is quite a leap from those small segments (not even a full skull or jawbone!) to the picture on the left, but that is what is required to support evolution on this scale.
I want to be clear when I say that there is a great deal of brilliant scientific work done by brilliant men in the effort to support evolution. It is just that there are extensive leaps of faith necessary (such as demonstrated above) to justify belief in the theory.
Now for the “improbability” part: math demonstrates that life as we know it today is so overwhelmingly improbable that the likelihood of it developing naturally is sufficiently close to zero to make it an untenable position. This results from the “anthropic principle,” which states that the universe is minutely fine-tuned to support life (specifically our life) in such a way that defies random chance. According to William Lane Craig:
For example, changes in the gravitational force or the electromagnetic force by only one part in 1040 would have precluded the existence of stars like our sun, making life impossible. A decrease or increase in the speed of the expansion by only one part in a million million when the temperature of the universe was 1010 degrees would have either resulted in the universe’s recollapse long ago into a hot fireball or precluded galaxies from ever condensing, in both cases making life impossible. The so-called cosmological constant, crucial to the development of our universe, must be inexplicably fine-tuned to an accuracy of one part in 1053 in order for a life-permitting universe to exist. These are just some of the many constants and quantities that must be fine-tuned if the universe is to be life-permitting. And it’s not just each quantity that must be fine-tuned, but their ratios to one another must also be fine-tuned.
…It is overwhelmingly improbable that a life-permitting universe should exist.
A common response from skeptics is that with billions of years and billions of worlds, life will arise somewhere, and the improbabilities resulting from the randomness of evolution disappear with the vast time and space available. Unfortunately for this view, “billions times billions” is still too small a number. A billion is 1 with 9 zeroes after it. A billion times a billion is a 1 with 18 zeroes after it. Just the probability of the correct amino acids being formed by chance to jump-start life is 1040,000 to one. That’s one with forty thousand zeroes after it. The number that results when you add up the probabilities of all the necessary naturally-occurring events is all but infinite. Again from Craig:
Moreover, it was originally thought that billions of years were available for life to originate by chance. But we now have fossil evidence of life existing as early as 3.8 billion years ago. This means that the “window of opportunity” in which life had to originate by chance is being progressively closed and is now only about 25 million years – which is far too short for the chance scenarios.
With all of this said, evolution and its associated theories best fit all of the evidence we have when applied with a very key component of most modern science: the “presupposition of anti-supernaturalism.” When it is accepted as an a priori fact that supernatural (above or outside of nature) acts are impossible, then natural causes and processes must be accepted, even if they do not fit the evidence. This is a fish story that is possible (albeit remotely), and must be accepted based on current knowledge if supernaturalism is to be dismissed. Of course, a supernatural cause – namely intelligent design of the universe – solves these problems quite well. It is the theory that best fits all of the data, and solves numerous other problems, as well. It is not an easy solution, because it requires a great deal of investigation into what it means to live in a universe with a creator, and then we must investigate individual religious claims and theories. It is actually unscientific to dismiss potential supernatural activity merely because it is difficult to test for; an entire segment of proof and reasoning is ignored, based on what is actually a philosophical, not scientific, belief.
 For the purposes of this post, I am including abiogenesis as part of the story, even though the two are not technically concurrent theories. They are, however, interrelated, since there is no need for evolutionary theory if there is no theory for how the first life originated from non-living matter.
 Cosmos. New York: Ballantine, 1985. pp. 20-21, 282.
 There have been experiments, beginning with the Miller-Urey experiment in 1953, that have shown the possibility of amino acids and nucleotides being produced in environments similar to that found on a young Earth. However, the problems associated with the extrapolation of these results (not to mention the re-creation of an unknown planetary condition) to a plausible origin of life continue to elude scientists.
 By “myth” in this sense I mean in the traditional sense of the word, which is a legend or story that explains a natural event. No more, no less. To borrow a line of reasoning from C.S. Lewis, we have enough words (fable, tale, et al) that mean a fantastical and imaginary story without trying to bastardize another to mean the same thing.
 See Behe, Michael J. Darwin’s Black Box: the Biochemical Challenge to Evolution. New York: Free, 2006.
 Another scientific difficulty is the required development of new species as a result of mutations. Genetic mutations have not been shown to create any new genetic information, contrary to the claims found in Wikipedia, et al. Traits never before found in that particular species may show up, but only as a recombination of genetic material already found in DNA.
 For more detailed information, see Chapter 4 in Geisler and Turek, I Don’t Have Enough Faith to Be an Atheist. Wheaton, IL: Crossway, 2004.
 Written in Zacharias, Ravi K., and Norman L. Geisler. Who Made God?: and Answers to over 100 Other Tough Questions of Faith. Grand Rapids, MI: Zondervan, 2003. p. 59.
 Fred Hoyle and Chandra Wickramasinghe, Evolution from Space (New York, Simon & Schuster, 1981), 24
 Written in Zacharias and Geisler, id.