I have no idea how you came to this conclusion.
Separate events, but both very full of symbolism and not scientific.
There are sciences working exactly on this. Just a little hint - it was not immediately.
No, this is just a claim of the YEC proponents, for this claim they need to:
a) read Genesis in a totally wrong way (scientifically instead of from the ancient perspective)
b) add and invent many ad-hoc solutions for it (one continent, no biological death before the fall, total recreation of almost everything after the fall, ocean of waters above firmanent that disappeared after the flood etc).
How did I come to these conslusions?
Teh scientific method to validate natrual "facts" requires testing repeating and observing! No one was ther when the big bang supposedly occurred nor can they verify that all their calculations and predictions
by gong in back in time. Same with creation. We can see support and evidences but no direct observation that would allow anyone to call either true!
As for Genesis 1 and 2 you know they are full of symbolism how? there is no warrant in the language to justify that. Only an allegorical interpretation allows for these to be symbolic. Then how do we know your allegorical view is better than many others?
The language in Genesis says they came forth fully grown at the beginning. They then continued by seed and growth from seed. Science can never verify the miraculous- science can only explain natural events- that is why science is now mostly athiestic /agnostic because they have been indoctrinated since grammar school to no tthink of God being involved in the natural world. That is also why most scientists mock the physical resurrection of Jesus! It just cannot happen that a person drained of blood can rise from the dead with full vigor and strength and a "better" body than what was buried!
And no these are not claims of YEC proponents. They are taking Scripture at its normal usual meaning of words!
We take the Scripture and then use it as a hypothesis and then research the hows and whats of the statements without discarding the divine miraculous!
I believe exactly what eh bible says- He put the waters on teh earth in one placed and called them seas. The antenoahic earth could have been a reversal of what we see today- it could have been 80% land and 20% water!
as for death of creatures, before the fall, I rely on Romans 5, and also Romans 8 and how they work in the greek! Those are intensely powerful verses that declare that not only all life but the entire universe suffered the curse because of adam (that is why God is going to destroy this present universe and create one without corruption)
Maybe you should ask yourself what would happen if a global flood took place?
Then look at Scripture then the geological and paleontological evidence!
Psalm 104 is a very scientific statement about where the flood waters went.
Let us look at that for a moment.
The fountains of the great deep were opened and deluged water. What would that create? Gigantic underground caves! As the pressure of the rising waters mounted- these areas would slump and make perfect places to form the new oceans. Great tectonic and volcanic activity! Flood scour land masses! Wiping them near clean!
They kill. And a flood like this would destroy one ecosystem at a time as the waters rose. And of course if there was water or vapor stored in some level of the atmosphere- we would not have that water today- it poured out!
Even science agrees in Pangaea- they just dispute when.