Thought you might find this to be an interesting read...
The dimensions of the ark were ideally designed for both stability and capacity. It has been shown hydrodynamically that the ark would have been practically impossible to capsize and would have been reasonably comfortable, even during violent waves and winds. Assuming the ancient cubit to have been only 17.5 inches (the smallest suggested by any authority), the ark could have carried as many as 125,000 sheep-sized animals. Since there are not more than about 25,000 species of land animals known (mammals, birds, reptiles, amphibians), either living or extinct, and since the average size of such animals is certainly much less than that of a sheep, it is obvious that all the animals could easily have been stored in less than half the capacity of Noah's ark, each pair in appropriate "rooms" (literally "nests"
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