In this video, Richard Dawkins discusses the laryngeal nerve, which travels all the way down to the heart, loops around an artery, and then goes back up the larynx. It has to innervate both the heart and the larynx, but of course, if an engineer were to design this, he would have it innervate the larynx first, then go down to the heart. Not the other way around. It even does this in the very long neck of a giraffe, which means that we’re talking about twenty feet of unnecessary nerve length.
As Dr. Dawkins points out, the only imaginable reason for this “design” is that we evolved from fish, which have no neck, and so it doesn’t matter that the nerve loops around like that. I wonder what creationists would use as a talking point here? Would they pull out the old “God works in mysterious ways” canard, or perhaps the ever-popular “there must be a good reason”? How about “why would God act like a human engineer, when he is God?” (the last one is particularly amusing, because the assumption that he “designed” every species rather than letting them evolve implicitly assumes that he was acting like a human engineer).