NOTE: One could consider this atheistic (or possibly deistic, depending on the person) “witnessing.”
Evolution is an affront for many theists because it rudely interrupts their fantasy of humans having a special place in the universe and in God’s Plan™. Even the most liberal of Christians have problems grappling with this issue because understanding evolutionary history leads one to the idea that humans weren’t inevitable. We could have easily never evolved, or died out long ago (which we actually almost did – there’s evidence that all of humanity had a population bottleneck at one point and may have been reduced to approximately 10,000 individuals). Even the liberal Christians will say that they believe in evolution but God guided the process towards us, or designed us specifically in the end in his image. We’re the big goal! Isn’t that great and comforting?
I could open a separate thread focusing on genetics and chromosomal fusion or the idea of encountering aliens or all sorts of other points to dispel such ideas. But I think it’d be amusing to gather all the screwed up designs of the human body instead. I’m sure you’ve seen some of these before but I’d like to gather them all in one thread because it’s actually quite compelling. If anyone wishes to add more I’d love to see it (particularly specialists; say, someone who knows a lot about the kidneys or some such).
The human body is a relic of natural selection, not an intelligent architect:
The first design flaws I’ll bring up haunt the minds of many theists and even our elected representatives. We deal with them everyday. This may sound silly at first but honestly think about it…
What the hell is going on between our legs?
Looking at the male genitalia induces laughter because it’s so ridiculous. Organs critical to the survival of the species are just hanging out in the open without a care in the world. The testicles are hyper sensitive to both damage and pain and their only protection is a thin sac of skin. Is this good design? There are reasons why they hang outside the body regarding temperature and sperm production. Why didn’t God change the design so we can make sperm in our bodies? He did it with cetaceans (dolphins/whales) and seals. Is it good design to have our testicles flopping around while we run away from a lion?
Ditto the penis. It’s not so vulnerable because it’s flaccid most of the time but the principle is the same. Most mammals keep their penis tucked inside their body for protection.
And then there’s the prostate. Many men know the results of an important tube going through an organ that has the tendency to swell. Was God drunk when he placed the prostate?
The female genitalia doesn’t escape scrutiny either, although it’s much better than the male’s setup. For one, why did God create the hymen? And what’s up with the clitoris? It makes sense when one understands the concept of homologous structures and how we develop in the womb. In the light of intelligent design, the clitoris is just bizarre. Why did God put it way up there, away from the vagina? That is to say, the clitoris is the seat of female sexual pleasure. The purpose should be to encourage sex. So why have a clitoris that is away from the action? Wouldn’t it be better to delete the clitoris entirely and relocate the nerve bundle to the vagina? This would make sense because it would be an improvement over the current situation where women have difficulty climaxing during sex and it would reduce a vulnerability – it’s just not a good idea to have a hyper sensitive button exposed to the outside world like that.
The female breasts should be a complete mystery to those who think God designed us. Why should females be burdened with carrying around huge lumps of fat and flesh by their chests? Ask the average person on the street and he’d probably say something along the lines of milk production, but even he knows that is false because we’ve all seen dogs or pigs feeding entire litters and…they don’t have huge breasts. Simply put, female breasts are abnormal by mammal standards. Even a flat girl is a buxom babe compared to a female ape. Breasts are the obvious result of runaway sexual selection designed to make guys excited. I don’t believe most intelligent design advocates are comfortable with this conclusion, first for moral reasons, and secondly because it’s not really good design, is it? It definitely works of course…but God didn’t have to design us is this way. We would be fine if women were completely flat and the male fascination with breasts was removed from our human nature.
Speaking of reproduction, the mechanisms carrying it out aren’t too hot either. Something on the order of 20-30% of all fertilized eggs are discarded by the body without the woman even knowing. Numerous perils and pitfalls await a developing embryo, many of which lead to spontaneous abortion and emotional trauma for the mother. So many genetic anomalies and just plain mistakes during the process of growing a person can result in either outright death or birth defects and a life of pain and suffering. Is this evidence for an intelligent designer in any way? Does God fail at genetics?
Even with our advanced medical technology both babies and women still die during the birthing process. The combination of our big heads and tenuous birth canals leads to disaster in some cases. Of course, we know the pain is God’s punishment on all women for Eve’s wickedness and that modern pain blocking medication is going against God’s will. 
What’s up with our backs, knees, and feet? It’s almost as if they were reverse engineered to adapt to our upright stance instead of someone coming up with them to suit our lifestyle from the beginning. I once saw a imaginative picture in Scientific American which showed what we would look like if we wished to get rid of our chronic problems in these areas and it looked quite amusing (can anyone find it online?). Why is God less imaginative than some random artist/researcher writing for SA? Why does he want us to suffer chronic pain?
Before the advent of modern hygiene your teeth would regularly rot and fall out due to excess plaque and tartar. Even today we must visit a dentist to have him scrape off what we miss. Is having your teeth fall out in your 20s good design?
The vast majority of all life on this planet can manufacture its own vitamin C, a chemical of great importance. We can’t. If we don’t get enough vitamin C from our food we become sick, bleed from all of our mucous membranes, and then die a painful death. A biologist would say that we inherited a mutation in the vitamin C synthesis process from our ape ancestors. Someone who believes God designed us can only wonder why God wants us to have to hunt for vitamin C every day while most of the rest of the animal kingdom make its own.
Why do we have the passages to our stomach and lungs intersect at our throat? This means a simple mistake will block our airway and kill us. A good designer would have these be separate holes in our body. We should be able to breath and eat at the same time. This isn’t too unusual of a request from God – cetaceans (whales/dolphins) have this setup to a certain extent, although it could be better in that case. So do fish and insects and, to a lesser extent, frogs. Snakes have a tube that allows them to breathe even while their entire throat is stuffed with their prey. Why does God seem concerned about snakes choking but not us?
Our eyes are wonderful instruments but they also have a critical flaw. They are wired ass backwards – the end result being that a portion of our light gathering capability is blocked by the optical nerve. Our brains have to hallucinate to make our vision seem normal. I’m sure we’ve all done the finger test at some point. Octopods have their eyes wired up in an intuitively correct way and hence have no blind spot. Maybe God made octopods in his image.
Why did God bless many animals with regenerative abilities but leave us out to dry? If you hack the arm off a starfish or the tail off a lizard they’ll simply grow another. Many animals grow new teeth all the time; if our teeth fall out, they’re gone forever. If we lose the sensitive hairs inside our inner ear they never come back and we gradually go deaf. Why, God, why?
Our digestive tracts are problematic. As a simple example, why are some people lactose intolerant and not others? Scientists know why – it’s a simple mutation which can be tracked in populations. But why would God design us this way? Wouldn’t it make more sense to make it so everyone can consume dairy products? Does he like those of European descent more than Asians and Africans and Native Americans? After all, he made it so we can eat ice cream.
Ditto allergies of any origin. Why does God want to deny his delicious creations from so many people?
The idea of a God designing humanity in the sense of an architect designing a building simply isn’t parsimonious with the facts we have assembled over the previous 200 years unless we radically change the popular notion of God.
