This is somewhat related to How did all the animals fit into Noah's ark? One of the comments read: "How does one propose to produce the various species/sub-species simply from 'some sort of cat', ...
Given that Noah had to rescue 2 of a kind of every animal and fit them all in the ark, and given that he would've had to feed them while they were in his captivity: If after the flood there were only ...
During the great flood Noah was ordered by God to fetch two animals of each species and put them into his ark. 19 And of every living thing of all flesh, you shall bring two of every kind ...