The book of Genesis isn't to be taken literally. The point of the "Creation Story" in a strictly religious context is that the earth was created for the purpose of God's plans; the "how" is irrelevant.
Furthermore, the careful observer will note that the book of Genesis is Moses's account. By my maths, that could be anywhere from 2,000 to 24,000* years after the fact. If you for a moment assume as a given that God did talk to Moses, then doesn't it stand to reason that God would have simply glossed over some bits of the story for brevity in order to get to more pressing matters? Perhaps the golden calf idol being constructed down in pinhead-ville?
In any event, people that interpret the Bible literally, and most specifically the OT, greatly amuse me.
* Many folks seem to think that 4,000 BCE is "the beginning," whatever the heck that is. I tend to associate the "family of Adam" with the advent of the Homo Sapien Sapien species. By my memory, our species has been around for about 26,000 years now. It also reconciles some anachronisms in the OT regarding races of giants, which I would then submit might be references to other un-evolved strains of hominids that needed to be purged to prevent interbreeding and therefore a recession in the gene pool. However, I'm not completely happy with this line of thought because it doesn't take a genius to figure out that evolutionary changes don't happen in gigantic leaps, but rather as incremental steps over periods of time.