Imagine that there are many universes, not just the one we live in, and that they can reproduce; that one universe can have many children. If there is some mechanism that universes can use to pass on their “genes,” we would expect universes to evolve.
Think of it this way. Say we start with two universes, one who births four universes and one who births twelve. These universes would in turn reproduce, passing on some of their “genes.” The very fertile universes would in turn produce many fertile children who would produce many fertile children and so on, until most of the universes are very fertile universe.
Or, to put it in terms of humans, imagine a world where stupid people have many more children than smart people and that stupid people tend to have stupid children. Given that this is the case, the earth will soon come to be populated by stupid people.
This idea was proposed in 1992 by Lee Smolin, who speculates that universes reproduce via black hole formation; each black hole contains the seed of a new universe. If this is the case, we would expect that most of the universes in the multiverse are fertile ones, ones selected for black hole formation. Thus this theory is pseudo-testable. If it’s true, we would expect our universe to be tuned for black hole formation.
This speculative theory leads to the intriguing hypothesis that intelligence is selected for because it somehow aids black hole formation. Maybe the reason that we look up into the night sky and fail to observe alien life monopolizing the universe’s resources is that they’re busy producing black holes.
You can read more about it here. There’s also a book on the theory called The Life of the Cosmos.