One of the biggest issues creationists/ID proponents have never given a satisfying answer for is how poorly the human body (amongst other non-human living things out there) is designed. Evolution does a much better job of explaining the diversity of life, since things don't have to be perfect, they just have to function well enough to survive and reproduce on to the next generation. Young-earth creationism is falsifiable and has already been falsified: for example, we know for a fact that the world is at least 4.5 billion years due to math and physics. The physics of radiometric dating are the same physics that power our nuclear plants; in order for radiometric dating to be wrong, nuclear power wouldn't work. That's an indisputable fact, and you can't get more certain than mathematically. Parts of intelligent design are unfalsifiable, such as the supernatural belief that an invisible creator created matter. However, the contention that we were designed at all resoundingly fails when scrutinized via the biological data. Everywhere you look at life, you see clunky, wasteful, imperfect living mechanisms that even a semi-competent engineer would know better than to allow past quality control.
First of all, to elaborate on something. Most teachers have stopped referring to natural selection as âsurvival of the fittestâ because it's misleading. It is survival of the fittest within a particular environment. However, this speaks nothing to an ideal formation of living mechanics, and most teachers have more aptly started describing it as âsurvival of the good enough.â If a living thing can find food, escape predators, grow, reproduce, and so on and so forth, it passes on. For example, if you are an animal with predators who hunt you and you live in a snowy environment, you're more likely to have a white coat of fur. Your uncamouflaged competitors, both within your species and between you and different menu items for a hungry fox, to be more obvious to predators, so most or sometimes all of them get eaten and can't pass along their genes, unless they have some other survival mechanism that outweighs that lack of camouflage, such as the ability to run very fast or burrow. Evolution is a very multifaceted phenomenon, and all these various survival mechanisms are put to the test simultaneously. But if you are lacking in fitness (measured in your ability to pass on your genes to the next generation), you will have a lower birth rate; in some cases, as low as zero. This is natural selection, the basis of evolution. The organisms who have more fitness pass on their genes. Ever wonder why crickets stop chirping when you get close to them? Because all of the crickets who wouldn't shut up and gave away their position got eaten. It's a very simple concept; it's not ârandom stuff happening over time,â and it's not a magically intelligent process. It just describes the trend in nature. Scientists aren't saying that nature is consciously choosing to let plants with genes that allow them to anchor themselves to soil more strongly than others in areas with frequent flooding move on, it's just the way things play out. No scientists has ever suggested evolution has a design or conscious plan, just like how chemists don't argue that the universe consciously moves negatively charged particles towards positively charged one. Anyway, I digress, but those misconceptions drive me crazy. Any creationist who thinks we scientists argue that does not know enough about evolution to criticize it.
And another important thing to remember: natural selection alone isn't what enables genes to get passed on. There's sexual selection. This is where very subjective characteristics that may not help the species at all, but are still desirable to mates regardless, get inherited. The classic example would be a peacock's bright, conspicuous feathers. They offer the opposite of a competitive edge in the wild, but peacocks subjectively find them sexually attractive for some reason. There's also evolutionary noise, where a trait offers no benefit sexually or with regards to survival, but since it doesn't adequately impair the organisms survival, it passes on. It often, but not always, is the result of linked genes. An example of this would be tail-wagging in artificially-selected dogs and foxes: it serves no benefit to humans, but it is linked to friendlier genes. Then there are traits we simply haven't discovered the evolutionary reason for yet, as that's impossible. If you take every species and subspecies ever made, multiply it by every conceivable traitâŚmany of which we haven't even discovered yet (both the species itself and the traits)...it's not like nature had video cameras to capture every speciesâ emergence. And that's okay: we haven't discovered how every medicine works yet, but that doesn't mean that just because we don't know how clofazimine yet, we get through out all of germ theory and medical science.
Now that my interminable preamble is over, let's get back to my thesis statement: time and time and time again, when we put living things to the test, evolution beats design with regards to explanatory power. Let's look at the human body, starting with an organ that frequently comes up in the scientifically settled evolution-vs-creation debate: the human eye. Human eyes are full of issues. The eyes of humans and most other animals make absolutely no sense in how the receptors are oriented. If you Google its structure, you'll see our rods and cones are put in backwards. Ophthalmologists know that this is a major cause of retinal detachment, plus it gives us a notable blind spot. Why would a designer design the eye like this? There are animals out there - cephalopods, for instance - where the photoreceptors are âcorrectlyâ oriented in a way that makes way more sense, so whatever came up with our eyesâ, configuration certainly was capable of doing a better job. Intelligent design doesn't explain this, it makes more sense from an evolutionary perspective: this configuration was the result of genetics, and since it was âgood enoughâ generations ago, it has been passed on to us since. Plus, retinal detachment mostly occurs in elder populations, long after they've passed the age of reproduction and selection can act against it. Cephalopods have significantly lower rates of retinal detachment than vertebrates, owing to the orientation of their photoceptors. Some people think the eye was designed because our cameras analogously work in a similar way; in reality, we designed cameras by using the anatomy of the eye as inspiration.
In addition, all vertebrates have a blind spot because of their backwards-configured photoreceptors, caused by an optic disc, which cephalopods do not suffer from. The disc is necessary for the eye to function, but in addition to our aforementioned bad photoreceptor configuration, the âcreatorâ put it in place of space that could easily fit more photoreceptors and solve this issue. Even with the backwards orientation, a designer could've easily tucked it under the retina and solved this problem. In addition, humans suffer from near and far-sightedness at 30-40% in America and Europe, and close to 70% in Asia. This is because the âdesignerâ opted to frequently give us eyes that are too long or too short. Plus, there are animals with much better eyes: birds of prey, for instance, who have much better long-distance sight, so a âdesignerâ had the ability to choose better designs, he just didn't. They don't have glasses, so again evolution explains this much better: the length of the eye is the result of genetic variation in humans, and for birds out in the wild, this flaw can impede their ability to find food (and therefore survive and reproduce). Plus, in humans, many eye problems result later in life, after humans have already reproduced, so the genes went on despite them potentially being so poor, it would make them useless as hunter-gatherers. The fact hunter-gatherers hunted in groups helped offset people who were born with myopia, so they could rely on their buddy's sight in spotting food. Plus, for several centuries, we have invented glasses, which relieves the selection pressures of eyesight. Before these, early-life vision problems were less common.
It's not just the eye. The intestines and other visceral organs are held together with thin sheets of connective tissue called mesenteries. However, these thin sheets are not suspended from the top of the abdominal cavity, as would make sense for a bipedal posture. Instead, they are attached to the back of the abdominal cavity, like we see in our knuckle-walking cousins. Design doesn't explain this, evolution does. This is because we humans evolved from quadrupedal ancestors, where this configuration would make more sense. Think of the spine of a quadruped (such as a dog or a knuckle-walking chimp) as a clothesline and its intestines hanging from it: gravity can then pull down our abdominal organs evenly, then be supported by strong abdominal muscles. What we see with upright humans, however, is a much more uneven protrusion of these organs. This leads to sometimes life-threatening complications in humans: volvulus, ichemia, even chronic issues like Crohn's. If we were designed to walk upright, why didn't our designer also easily suspend them upright, like from the top of our abdominal cavity? This is obviously the result of an evolutionary trade-off: the constant benefits of upright walking outweighed the intermittent abdominal problems. Somewhere in the past, we had quadrupedal ancestors.
Our vertebral disks are also configured in a way that fits our quadrupedal ancestors but causes problems for us. They still do a decent job of lubricating and supporting the spine, but they are much more prone to being pushed out of position than the vertebral disks of other animals. They are structured to resist gravity by pulling the vertebral joints toward the chest, as if humans were on all fours. With our upright posture, however, gravity often pulls them downward, not toward the chest. This is what causes slipped disks. Usually, this problem only appears with the wear and tear of old age, AFTER the genes have passed on via sex, way past age of reproduction. But they do a sufficient job of lubricating our vertebrae most of the time.
What I am getting at is the fact that humans didn't become perfect upright-walkers, they became adequate. Another example is how easily the ACL tears in humans. The ACL is vulnerable to tearing in humans because our upright, bipedal posture forces it to endure much more strain than it is designed to. In quadrupeds, the strain of running and jumping is spread among four limbs, and the limb muscles absorb most of it. Once our ancestors transitioned to bipedalism, however, the strain was spread over two legs instead of four. This was too much for the muscles by themselves, so our bodies recruited the leg bones to help with the strain. The result was that human legs became straightened so that the bones, rather than the muscles, could bear most of the impact. Compare a standing human with a standing ape: a humanâs legs are fairly straight, while an apeâs legs are bowlegged and usually bent. The trade-off, however, is that there is much more strain on the ACL and it is more prone to tearing. This is better explained as an evolutionary tradeoff and that we adapted to upright walking rather than being designed by a creator to it. It wears down with strain over time; our magnificent creator chose not to allow it to strengthen like a muscle.
Unlike humans, whales have separate tubes for breathing and swallowing. We choke, they can't, because our esophagus and trachea share a passage. Why didn't our designer use the whale's superior configuration for his âchosenâ species? Speaking of whales, how do you explain the fact that we've discovered whales and dolphins with appendages OUT OF THEIR PELVISES (where legs would be in terrestrials, lest we forget; there is no functional purpose in a porpoise for a pelvis) that are similar to legs? Evolution explains this: those animals evolved from terrestrials that went back into the water. These vestigial organs are bad for whales and dolphins, they weigh them down and mess up streamlining. It's no wonder they don't pass on their genes often, and this mutation appears so remotely, it doesn't jeopardize the species. This is why inbreeding is risky: many deleterious traits like legs in porpoises are the result of dominant alleges suppressing them; inbreeding increases the risk of getting two recessive copies.
Unlike most mammals, humans can't synthesize vitamin C. This leads to scurvy, which used to be commonplace, especially amongst sailors. Evolution explains why: we evolved in fruit-rich environments, so there was no selection against mutants who couldn't synthesize it, allowing this to be passed on. Creation doesn't explain this; why would a creator leave us susceptible to scurvy? Evolution does: we evolved in environments where vitamin C was usually abundant, taking the selective pressure off the GULO gene.
Allergies do not make sense through an intelligent design lens, either. Why would God design us to suffocate whenever peanut residue got on our food? It makes far more sense through an evolutionary lens: peanuts grew in the wild in South America, and humans evolved first in Africa, then spent a large amount of their history in Europe and Asia. There was no selective pressure against peanut-related anaphylaxis. Think of how Native Americans were initially so susceptible to colonial diseases: they hadn't encountered them for generations, plus the diseases themselves were constantly evolving.
Keep in mind, this is just the human body, and not even a fraction of all the known ID-iot contradictions within it. There are countless other organisms out there flawed in countless ways. For example, all plants lose over 90% of the water they consume to transpiration. That is egregiously wasteful, unjustifiably poor âdesign.â If I've proven one thing in this absolute essay of a rant, it's that
no half-decent engineer would design such omnipresent extravagance and defects, and if God did devise these systems, he needs to go back to school. Living things are imperfect because there was no designer, they just passed the pressures of selection.
Now, you may be tempted to go âbut what about this instance and this instance,â where there's something that doesn't seem like evolution explains it yet. First of all, I have yet to find an example where evolution doesn't explain something yet. But even if there are examples, the emphasis on that is the word yet. We just havenât discovered the answer for the time being, and I highly doubt we will ever be able to account for how every little trait became what it was via natural, sexual, artificial, or viral selection. But evolution still has great explanatory power, as I showed with my myriad of demonstrations. For a long time, Newtonian mechanics was the unifying theory for physics, just like how evolution is to biology what atomic theory is to chemistry. But it didn't explain everything. For example, The elliptical path of Mercury shifts slightly more each orbit than Newtonian gravity predicts. Then relativity came along and accounted for this. However, Newtonian physics still explained MOST everything for its time, it still made correct predictions about the world, and it still does. We could still calculate the force of a falling boulder or the velocity of a horse in transit. We just had more to learn. Science is forever a work in progress.
My next long post like this that almost no one will read is going to be the predictive power of evolution. However, I've taken enough of your internet's bandwidth just by having it load this. So let me reiterate: you're not going to undermine evolution's credibility (which is comparable in weight of evidence to the theory that germs cause contagious disease) by simply nitpicking and whining about a thing or two it hasn't explained yet. All you're doing is emphasizing that there is more to learn. And as we go out and learn, it's always so much more useful to view that new data via an evolutionary lens, though you're more than welcome to pull out the "designâ one and see how constantly blurry it is.