" You can't calculate the probability of an event occurring which has already occurred. To use an example, what's the probability of Donald Trump being elected president? " MH #106
I disagree.
What were the odds of Michael Phelps winning a 2nd gold medal?
Phelps won a 2nd, a 3rd, & a 4th, & a ...
What are the odds President Obama would be elected a 2nd time? He did, in 2012.
If it rains in Pakistan, what are the odds it'll also rain in Peoria?
That a chemical compound starts replicating in one part of the ocean* doesn't prevent either an identical compound from replicating elsewhere, - OR -
a different potentially better chemical from replicating near-by, or far away.
* We can't use modern terminology, ie "Indian Ocean", "Pacific Ocean" etc. because over these geologic / biologic time periods, continental drift has redefined it.