Then why do so many fundamentalist Christians take Genesis literally?
Ya got me. Some of us can appreciate it for its allegorical value--it is a beautiful tale of a loving God creating everything. Lots of us realize that, for the majority of the illiterate masses, storytelling was the only way to spread a message and a concept. So, for those early Jews who couldn't read or write, stories were told to make the point that YAHWEH is behind the whole Universe, period. The hows are up to us to discover.