Noah’s Ark – Easily Believable

You shouldn’t try to argue with God. It’s almost universally fatal.

Back when genocide was an acceptable form of behavior modification, God decided to kill everyone except Noah and his family. Noah had to build a giant boat (Ark) and put two of every kind of unclean animal, male and female, and seven of every clean (i.e. delicious) animal in it. Then there was a huge flood that killed every person and every animal not on the boat. It’s a well-known, faith-promoting story about how awesome god is, and how important it is to follow His rules (Ref: Genesis 6-8).



Animals boarding the Ark; especially the dinosaurs

Many people who love the bible far less than I, try to discredit the entire book by attacking the story of Noah’s Ark. They make crazy claims like, “There isn’t enough space for all the animals” and “The technology of the time was insufficient to build a wood vessel of that size.” If you’re concerned about that sort of stuff, you can now rest at ease, because I am going to prove it’s possible using math. I think math is something we can all agree on. Yay for math!

First: the available cargo volume of the arc

God told Noah to build the Ark 300 cubits by 75 cubits by 30 cubits (Genesis 6:15). Using the standard, accepted conversion for cubits to feet (1 cubit -> 1.5 feet) this gives us 450 feet by 75 feet by 45 feet. If the Ark was a perfect rectangular prism AND Noah used God’s guidelines for the interior dimensions rather than the exterior dimensions, it would have a volume of 1,518,750 cubic feet.

Rectangular Prism

 Of course the Ark wasn’t a rectangular prism. It had curvy corners, and the biblical dimensions are assumed to be exterior. The Ark was probably made of a multi-directional composite wood structure (similar to plywood) about a yard thick at the base to give it the strength to support itself, and got thinner near the top to save on total weight. Then the Ark needed internal structure to keep the humans from living directly with the animals and to keep the animals from ending up in a giant pile at the bottom. This means there were multiple levels with the corresponding support structure and possibly interior walls. Let’s assume all this only represents a 15% loss in total volume, which is probably possible given Noah’s divinely inspired carpentry skills; honed through 600 years of life. This gives us an interior volume of 1,290,940 cubic feet.

Second: the apparent problems

There are currently around 1.2 million known species of animal. There are more than 10,000 different types of birds alone. Unfortunately the vast majority of species are unknown. Typical estimates put the total number at no less than 7 million different species, and some are much higher. Don’t worry though; most species live in the water and Noah only had to take the land types. If 75% or all species live in the water, that only leaves 1,750,000 different species for the Ark and most of these are much, much smaller than one cubic foot. If God was helping to gather and load the animals, and they boarded the Ark day and night at a rate of five seconds per species, it would only take two months.

This all seems like it would be great, were it not for Genesis 6:21, “And take thou unto thee of all food that is eaten, and thou shalt gather it to thee: and it shall be for food for thee, and for them.” That’s right, Noah had to load food. Noah and the animals lived on the Ark for one year and ten days (Genesis 7:11 and Genesis 8:13). That is a LOT of food. An average horse eats about three tons (6,000 pounds) of food a year. If that’s all alfalfa, two horses would need 1,800 cubic feet of feed, if the alfalfa was compressed into bales. If it was loose, as it would be in Noah’s time, the two horses would need 3,000 cubic feet.

Let’s assume all the animals ate, on average, one pound a year. This would give 1,750,000 pounds of food. At the density of baled alfalfa this is only 175,000 cubic feet. Hey! It still works! Well, maybe not because each animal needs slightly more space that its body actually occupies. They can’t just be all packed in there like sardines or there would be no survival for 375 days. Even intensive pig farming operations need SOME space, and some pretty fancy technology to keep them from overheating in crowded conditions. 1,750,000 different species now seems like a bit of a stretch, especially with God limiting Noah to three levels (Genesis 6:16). This only gives Noah about 90,000 square feet of surface after taking walls and support structure into account, and giving up 5,000 square feet for food storage and the humans. This gives an average of 0.026 square feet (3.7 square inches) of deck per animal, which is probably not enough, and I probably underestimated the amount of food too. Good thing I have the solution, eh?

Third: the solution

If you carefully read Genesis 6:19-20, almost every single English translation calls for two of every kind or sort of animal. Noah didn’t have to take two of all 36 different known species of wild cat. He only had to take two felines. Similarly, he didn’t need to take all the different types of donkey, horse, and zebra; he just needed to take two animals from the family Equidae. Only the birds needed all 10,000 species (see Genesis 7:14). This cuts down on the total number of animals real fast. Also, many of the land based worms, snails and microscopic animals probably didn’t end up on the arc and survived by floating around on debris. Noah didn’t even take the Unicorns (per the Irish Rovers song: The Unicorn).

Of course you may ask, “If Noah didn’t take all the animals we are familiar with on the Ark, how is there so much biodiversity today?” This is easy. Prior to the flood all the land on the planet was in one place, and was relatively flat. Genesis 7:20 says that 15 cubits (22.5 feet) of water covered the hills and “mountains” of Noah’s time. It was five generation later, after Peleg was born, that all the land was violently divided into its current configuration (Genesis 10:25). The high mountains, deep valleys, and isles of the sea were formed at that time.

Note: the New Living Translation of the Bible presents this differently than all the other English translations, which appear to agree with me.

After the kinds of animals were split up into radically different environments, they adapted into their current forms (except the birds, which were all saved on the Ark).

See? It’s easy to explain if you know how.


Note: if you are looking for an entertaining analysis of the Ark story that is less supportive of its veracity, check out Ricky Gervais' stand up bot on Noah's Ark. Here is the youtube video.