The world that we see today is not the one that existed in Noah’s day (2 Peter 3:6). That land was destroyed. In fact, it appears that the original continent was broken up and the pieces separated by thousands of miles.
Ever heard of Pangaea? Ever heard of plate tectonics? Skip that class? A single continent would have made it possible for all animals to walk to the Ark.
We get a glimpse into this different world in Genesis 1:9–10. On Day Three of the Creation Week, God gathered the waters together into “one place,” separate from the dry land. Somewhere on this land was a lovely place called Eden, out of which four great rivers flowed (Genesis 2:8–10). Nothing like that exists today. The entire face of the Earth was wiped off and covered in thousands of feet of mud, silt and debris.
Most non-believers think millions of animals could not fit on the Ark, but their misconception would be in error because of a false presupposition. Start with a false presupposition, and your conclusion is probably false.
The Bible says Noah took only air-breathing land animals. So that excludes sea creatures and possibly insects and other invertebrates. Of the land vertebrates, there are only around 33,000 named living species (and a few thousand more fossil species). These are divided into fewer than 10,000 genera and 1,000 families. So how many kinds of animals were on the Ark? The answer depends on which modern taxonomic level—order, family, genus, or species—represents each original “kind.” Two times 1,000 gives about 2,000 land-dwelling vertebrate animals that Noah had to care for. Impossible? Not at all.
Without tiering of cages, only about half of the Ark floor would have been necessary to house all of the animals required on the Ark and these could all fit on one level (out of three levels). What’s more, many could have been housed in groups, which would have further reduced the required space, leaving enough room for a large play pen as big as a tennis court.
They had decades to prepare for this journey and likely were saving seeds and growing food in planters and pots to transport to the Ark. The upper deck could easily accommodate a large garden.
The dimensions of the Ark are convincing for two reasons: the proportions are like that of a modern cargo ship, and it is about as large as a wooden ship can be built. The dimensions are less than half the Titanic or Queen Mary.
There were large wooden ships of similar length built with the same level of technology in ancient times in far less time: The Greek Tessarakonteres 200 BC 420' x 52'.
The Bible does not tell us that Noah and his sons built the Ark by themselves. Noah could have hired skilled laborers or had relatives, such as Methuselah and Lamech, help build the vessel. However, nothing indicates that they could not—or that they did not—build the Ark themselves in the time allotted.
If one or two men today can erect a large house in just 12 weeks, how much more could three or four men do in a few years? Adam’s descendants were making complex musical instruments, forging metal, and building cities—their tools, machines, and techniques were not primitive. The idea that more primitive civilizations are further back in time is an evolutionary concept.
Impossible? Not at all.
If we count the generations back to Noah, it would be about 150. The Flood was roughly 4,500 years ago. Average generation span of 30 years. Divide 30 into 450, and you get 150 generations. Sure, it's a rough estimate, coincidence that it's so accurate (like most of the Bible)?