I have a theory about the (either "creation" or "emergence") of life on any planet, anywhere.
It is complete conjecture in my own head, period...
I think it's entirely possible that it actually requires a GALAXY in order to form all the necessary elements, via supernovae, degenerate star collisions, etc, over immense timescales, to even make it possible at all...
I also think it's entirely possible that even if a galaxy manages to produce the right elements not all of them will result in the "creation or emergence" of life...
To those who want to throw a "God" angle into this - what's to say said "God" isn't playing by his own physical laws HE created for THIS UNIVERSE, that HE created?
After all, HE would be ABOVE this universe - and could have many of them, playing by the rules of each one, that HE CREATED......