I think you've left something out - but it is kind of subtle.
Then all the animals got off the ark and we had hyper-evolution for the next 4000 years to leave us with the wildlife we see today.
Since Noah built the ark and the shit pump 4,500 years ago this 4000 year period of warp-speed evolution continued until 1500AD or so - maybe even more recent than that.
As far as I am aware there is no record anywhere - either written or in an oral tradition - that suggests anybody saw new creatures magically appearing, particularly by direct birth from a (different) known type of creature.
Sure there are plenty of accounts of new creatures being seen, but only when people go to a new place (i.e. the European voyages of discovery and conquest from the 15
th. Century onwards) which is where you'd expect to find 'new' animals. Of course, they weren't new, they were just previously unknown - the locals knew all about them.
I guess the hyper-evolving critters were just shy and hid away from humans, which is why it wasn't recorded by the Jews, Greeks, Romans, Phonecians, Babylonians, Egyptians, Chritians or Muslims. Oh, not forgetting the Chinese, Japanese, the whole of S.E. Asia, Indians, Native Americans, Australian Aborogines, Polynesesians, the Inuit and well, everybody really
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