The story of the flood, like the creation story itself, makes sense only as a fable or legend, not as scientific history. I know many who believe these stories literally happened won't be convinced otherwise by me, but even if we ignore the impossibility of a sudden earthwide flood, the sheer logistics involved in collecting and keeping all the the animals on earth alive is beyond anyone. Who went down and collected the koala bears? What did they feed the lions? Were there polar bears? Grizzlies?
It isn't just young earth versus old earth, it's small-world versus big world. The fable works on a small earth... not a big one.
You liberals have no faith. The power of God is never considered, and is always discounted. Read the scripture - only two of each kind was brought (by God) to the boat.