How did Noah stuff at least 4 million creatures into the ark?
By the most conservative estimates, there are at least 2 million different species. The dimensions of the ark given in the Bible (converted from cubits) were 450′ x 75′ x 45′ or 1,518,750 cubic feet. That means that each creature only got an average of 0.38 cubic feet of space for itself and almost one year’s worth of food. (Smaller species such as hummingbirds and insects often consume up to their body weight per day. Which means even a hummingbird would require over 1 cubic foot of space just for itself and it’s food. Never mind the elephants.) How would this have been physically possible? Scientifically speaking, it wouldn’t.
Those who believe the Noah’s ark story sometimes attempt to reduce the number of species to “kinds” but that doesn’t explain the unprecedented evolutionary “explosion” which necessarily had to follow immediately after the flood. There is zero scientific evidence of this ever actually occurring.
Another commonly espoused “theory” is that all of the animals went into hibernation for over a year and didn’t need to eat. While some animals other than the well-known bears can enter a hibernation-like state when food is scarce, few, if any, can sustain it for a year or more. Even so, many insects have a life-span of much less than a year. They would have to have been awake to reproduce, wouldn’t they?
There are countless other logistical problems which fly in the face of science when attempting to consider the Biblical account of Noah and the Great Flood literally: How did Noah gather and redistribute the animals from Australia – was there only one continent in 2348 BC? Where did all the water come from and where did it go? Was the Earth nearly flat in those days? How did saltwater fish survive for so long in fresh water – assuming the ark did not contain a massive saltwater aquarium? How was it even possible to engineer and construct a functional wooden ship of that unprecedented size (arguably the largest ever built) in the late stone age/early bronze age. The list of scientific impossibilities goes on and on.
Conclusion: The flood story is probably just that, a story. It is an allegorical account which is probably not meant to be taken literally. There may have been a massive local flood on which the story is based but it did not/could not have covered the whole Earth. There would at least be some scientific evidence left behind. Ocean fossils on the tops of mountains don’t count. They may have inspired the story to some degree but they are more than adequately explained by tectonic action.