Literal belief in the flood story

[Esquilax]

Single land mass? You believe that 5,000 years ago, the Earth's land mass was one?

You're new, so let me help you understand: GC believes whatever he needs to in order to validate the bible, up to and including things that directly contradict other things he's had to believe to validate the bible in the past. His response to your question will roughly be "you can't prove it didn't happen," and it will be phrased in the most condescending way he can muster.

It makes interacting with him deeply pointless.

Edited to add: As regards migrations, did all the Australian animals, many of whom are not aquatic, swim to the ark?