When one reads the story of the great flood in the book of Genesis, one is struck by the matter-of-fact style of the narrative. While it definitely has the larger-than-life flavor typical of legends, the reader would not suspect that he or she is dealing with the bizarre impossibilities we have detailed above. After all, the ancient Hebrews lived on a small, disc-shaped world with a dome overhead and waters above and below. There were only a few hundred known animals, and subjects such as ecology, genetics, and stratigraphy were not even imagined. The deluge was a mighty act of God, to be sure, but nothing that the ancient Hebrews would have found too extraordinary.
When, however, this same story is brought into the twentieth century and insisted upon as a literal account of historical events, a considerable change is observed. No longer a simple folk tale, it has become a surrealistic saga of fantastic improbabilities. Events which seem relatively straightforward at first glance—building a boat, gathering animals, releasing them afterwards—become a caricature of real life. The animals themselves are so unlike any others that they may as well have come from another planet; genetic Frankensteins with completely unnatural social, reproductive, and dietary behavior, they survived incredible hazards yet remained amazingly hardy and fecund.
How can we account for this transformation? Put simply, the tale of the ark grows taller in inverse proportion to the advance of science. Two centuries ago, when biology and geology were in their infancy, the theory of a worldwide flood as a major event in the earth's physical history seemed perfectly plausible and, in fact, was advocated by various scientists.
Notice Moore’s underlying assumption: the flood account is unrealistic because the primitive, unscientific author didn’t know any better. People back then were in no position to ask common sense questions about the logistics of the flood.
Let’s compare Moore’s assumption with some of Augustine’s observations on the flood account, as he considers various objections to the account by critics of the day:
For, not to mention other instances, if the number of the animals entailed the construction of an ark of great size, where was the necessity of sending into it two unclean and seven clean animals of each species, when both could have been preserved in equal numbers? Or could not God, who ordered them to be preserved in order to replenish the race, restore them in the same way He had created them?
But they who contend that these things never happened, but are only figures setting forth other things, in the first place suppose that there could not be a flood so great that the water should rise fifteen cubits above the highest mountains, because it is said that clouds cannot rise above the top of Mount Olympus, because it reaches the sky where there is none of that thicker atmosphere in which winds, clouds, and rains have their origin...They say, too, that the area of that ark could not contain so many kinds of animals of both sexes, two of the unclean and seven of the clean...As to another customary inquiry of the scrupulous about the very minute creatures, not only such as mice and lizards, but also locusts, beetles, flies, fleas, and so forth, whether there were not in the ark a larger number of them than was determined by God in His command...
For Noah did not catch the animals and put them into the ark, but gave them entrance as they came seeking it. For this is the force of the words, They shall come unto you, Genesis 6:19-20 — not, that is to say, by man's effort, but by God's will.
Another question is commonly raised regarding the food of the carnivorous animals,— whether, without transgressing the command which fixed the number to be preserved, there were necessarily others included in the ark for their sustenance...
There is a question raised about all those kinds of beasts...propagated by male and female parents, such as wolves and animals of that kind; and it is asked how they could be found in the islands after the deluge, in which all the animals not in the ark perished, unless the breed was restored from those which were preserved in pairs in the ark. It might, indeed, be said that they crossed to the islands by swimming, but this could only be true of those very near the mainland; whereas there are some so distant, that we fancy no animal could swim to them.