I was drawn into Christianity primarily by the young earth creationist book, “The World that Perished” by John Whitcomb and remained a defender from age 16 to age 24 when I finally decided I wasn’t really sure of anything. Most modern young earth creationists believe in genetic conservation, limited speciation, genetic degradation, and extinction, but deny that genetic change through natural selection can add up to greater levels of complexity over long periods of time. Since the slow accumulation of complexity isn’t something immediately (or at least easily) observable I always realized the debate with evolutionists is really about a tiny percentage of genetic change that may be going on in the world right now in any given species... And to be fair (in hindsight), how exactly would you prove that wrong? If creationists aren't going to demonstrate their god's magic in the lab, why do evolutionists have to prove their case even if they are arrogantly overstating it? Last time I checked an argument from your ideological opponent's arrogance is not sound. Why shouldn’t intellectually honest people at least be agnostic on the creation/evolution debates (and therefore whatever follows from them)? I've since moved beyond agnosticism on the issue.
Ultimately most doubters of evolution seem to want to know why a copy of a copy of a copy doesn't just degenerate to extinction over a long enough period of time regardless of the curbing of natural selection and all of the mistake fixing mechanisms currently in place in cells. It is at least a fair question that deserves a direct response regardless of unrelated misconceptions about the second law of thermodynamics that are often pointed out by defenders of evolution. Pointing to other good evidence that indicated complex organisms arose from simple ones doesn’t exclude some magical mechanism. Some sort of magical vitalism might be true underpinning subtle changes in species over long periods of time. Responses from evolutionists like, "There are examples of limited self organization like snowflakes," while relevant to a degree don't seem to address the sheer magnitude of the accumulated complexity. It is more like expecting Superman's Fortress of Solitude to emerge from a random crystalline structure rather than extremely advanced Kryptonian engineering. So why would natural selection work?
Numbers. Human “middle world” sensibilities wildly diverge from reality here because of the “magic” of extremely large numbers. If you ask your average person, for example, how much money they would have if you doubled the amount of money you gave them every day for one month, starting with a penny (then giving them 2 pennies, then 4 more, then 8, etc.), none of them will predict anything like the correct answer. Most say maybe a hundred dollars, maximum, but the real answer is over 10 million dollars. Math. We’re intuitively bad at it. This is a problem when we're evaluating the most likely outcomes of certain complex physical processes that seem to run counter to our estimations (especially if we have some serious emotional investment in the outcome for the legitimacy of our favorite religion). What happens when the outcome actually hinges on the technicalities off our human radar?
Self-replicating molecules know no such limitations. For example, in just one species of bacteria alive today on earth, trillions of replications are occurring every single day. That means that absolutely perfect copies will be made rather often by sheer chance alone and hence will preserve that replication process absolutely indefinitely. So that’s why stuff doesn’t have to degrade in principle.
Note, according to mainstream science, life wasn’t doing much more than single cellular replication for three whole quarters of the last 3.8 billion years. It was just getting really, really really, really, really really, really good at making various spins on the most basic units of life. That’s kind of like being a baby for 2.8 billion years and then deciding you’ve mastered crying and pooping in your diaper well enough before you’re ready to grow up.
Now if you’ve filled up the planet with a variety of replicators which are ultimately immune to degradation thanks to math, odds are that something is going to manage to do even better than “perfect replication” and inadvertently start to climb even higher on the complexity and innovation scales. The continuance of life depends on replication and you don’t need more than the single cellular world to do that really well. Single-celled organisms are still with us in the gazillions and don’t need us to pick up the slack to keep up the charade. Anything above and beyond that is pure numerical privilege and escalation as replicators compete with each other for resources in varying environments. I think Lieutenant Gordon said it best:
Jim Gordon: What about escalation?
Jim Gordon: We start carrying semi automatics, they buy automatics, we start wearing Kevlar, they buy armor piercing rounds, and *you're* wearing a mask and jumping off rooftops.
Suddenly, Batman! You get where this is going. The substitution for the human intentionality in this analogy (since evolution is not an entity in and of itself, has no awareness or foresight, and no particular goal in mind) is the idea that random chance variation of replicators ends up trying out all sorts of replicator possibilities and the replicators that happen to have an advantage in relation to their competitors in a given environment will be the ones inevitably surviving to produce more offspring. It’s all pure physical logistics. So juxtaposed with bare replication, the human brain that can actually contemplate all this incredulously is pretty gratuitous, but only incidentally gratuitous and certainly not representative of what evolution has generally produced in the vast tree of life.
So where are all the transitional forms? Well, even if we didn’t have the fossil record, they’re still here. There are still single celled organisms, multicellular organisms, fish, amphibians, reptiles, mammals, monkeys, and your parents. [Unless you are Batman, sorry!] One would think that if creationists wanted to ask why there are still monkeys, they would actually be asking why is there anything at all besides humans (as though everything is supposed to evolve in lockstep)?
A creationist asking for transitional forms between humans and mammals who happened to have never been exposed to the entire primate order would likely be blown away by the evidence of many different species of primate who are almost upright, really smart, and share many basic social characteristics with humans. Remember, a god wouldn’t have to create people and animals with anything in common at all and yet the process of evolution would require this to be the case. Why do humans commonly have knee and back problems, occasionally have vestigial tails (some of which can actually move with muscle control), why do humans get goosebumps which in other species the same mechanism is meant to puff out a full coat of hair to be intimidating, and why do we have jaws too small to hold our wisdom teeth in? Is it because Adam and Eve looked a lot more like monkeys than modern creationists would be comfortable with? Doubtful. More than likely it's because we have a common ancestor with our fellow primates.
On top of that, why is it that snakes, dolphins, and whales have been found with vestigial legs? Is it because a whimsical, sex positive god wanted to allow some lucky whales to curl their toes during sex? Or is it because snakes have legged lizard ancestors and aquatic mammals have land mammal ancestors as we would expect from the tree of life if evolution brought the current species into being?
We have E-Coli bacteria that were able in the lab over many generations to mutate and start processing nylon, a synthetic fabric invented recently. The bacteria does this extremely inefficiently, but it does do it. And we have every generation of those bacteria preserved on file and we can identify which mutations enabled this to happen. What do you suppose would happen if these bacteria were left to their own devices for millions of years? They’d probably leave behind ancestors much more adept at processing nylon.
I have lots of incredulity about young earth creationist explanations if it's a debate about your incredulity about naturalistic explanations. Whose incredulity wins the day if we're being fair? Dendrochronology seems to very straightforwardly leave no room for Noah’s flood. Google it. Modern Creationist organizations still have no explanation for the massively excessive radioactive decay in fossil layers which would have boiled away the oceans if released in the same year. Even if the radioactive decay can magically be there and then the heat be magically taken away...why in the world did those geological processes go through that charade at all? It also seems like there is ample opportunity to find the absolutely wrong animal in the wrong layer of geology to disprove the general evolutionary scheme of things and yet somehow there's still a massive worldwide consensus the evidence generally lines up according to evolutionary expectations. Conspiracy? Shouldn't both extant and extinct similar types of creatures have been found in the same strata if it was just about the hydrodynamics of one worldwide flood? There’s the issue of how creationists have to expect more evolution than evolutionists in the last 4,000 years since Noah’s flood to account for the supposed 16,000 representatives of the "created kinds" being crammed into one boat and then diverging into the many millions of species we see today. Etc. Obviously there's lots of issues here few of us are qualified to fully resolve. For the basics of the evolution side of things, I would recommend to my creationist friends to read carefully through Douglas Theobald's handy "29 Evidences for Macroevolution" online (and even read the creationist Ashby Camp's responses) and Jerry Coyne’s “Why Evolution is True." Or just read the wiki page on evolution. There's tons of stuff around the internet.
I recall the feeling even at the very beginning of my creationist career of John Whitcomb magic-bulleting the Noah’s flood explanation against the general trend of geological evidence which Whitcomb himself was presenting. It made me uncomfortable even when I wanted it to be true. To the extent I have been able in recent years to scrutinize the back and forth between creationists and evolutionists, I’ve always found evolution to be very friendly with the mutually converging lines of evidence while creationists could only stretch hard to accommodate it. That is, after I retrained myself from creationist-think to not think in black and white categories and was willing to weigh evidence for the sake of dueling cumulative cases. With unfair standards of evidence the theory of evolution couldn’t beat a gnomes-made-everything-yesterday belief system either. That’s nothing to brag about if you’re a gnomist or if you happen to believe in merely an older young earth creationism.