According to Genesis, man was formed by God out of dust with these words, "Let us make mankind in our image, in our likeness". This single passage is used to deny evolution. This single passage versus the fossil record. Alrighty then. If you intend to assert that I am formed in His image, and he is perfect, even as a human, can you explain why His penis is designed to compete with other men's sperm?
The penis is designed as a pump. Not like a piston in a motor, but a suction creating device designed to pull out the sperm of the sexual partners that have ejaculated in your female partner before you. The head smoothly goes into the vagina and allows the competing semen by and then is scraped out by the edge of the head. At the same time, suction is caused and another thrust commences. The larger the penis, the better the seal, the greater the suction, the more successful your sperm can be. The longer you can last without ejaculating, the more of the competitors sperm you can remove, the better chances you have of success. Compare the human penis to any other primate, proportionally or in terms of overall size, and it isn't even a competition. If you were to look at it, you might claim that someone designed it, but that would mean at least one of two things.
Clearly, I would assert that the penis developed by the forces of Natural Selection. But design claims lay some serious expectation questions at the feet of God. You might claim that humans have choice in their sexual drive. How can I refute that empirically? What you can't do is deny the function of the penis. Did Adam have this type of penis before the fall? While they were alone in the Garden? Did his sperm ever feel the need to compete as it would today? If so why? If not, is it evolution that is driving the change?
Claims of God and design are silly. Often we talk about poor design, but how about this great functional design that points to purposes and uses that are contrary to any teaching of the Bible? If you are a design proponent, what say you about God's phallic? Is it like ours? Is he afraid that someone else is getting a little from his unknown bride? (Jesus! Get off ofyour step-mother!) Isn't it just more realistic to say that we used to get it on like Bonobo's and that sexual infidelity led to sperm competition and eventually penis competition and selection? It's that or God is a perve.