Re:Observable Universe contains 10x more galaxies than previ...
by Retric on Thursday January 04, 2018 @03:27PM
(#16073753)
Why not both. We could also be descendants of an invasive alien species that killed off all of Earth's native lifeforms.
It's good practice to assume the simplest possible solution. However, the full range of the full range of what might have happened is ridiculously large.
It's also possible it evolved elsewhere and rode here on a meteor - or was brought here by some other lifeform several orders of magnitude more advanced than us, using earth as their own cosmic terrarium.