Well, it's hard to say.
If the theories like the strig theory or the M theory are correct, then parallel universes should indeed have humans.
Also, if the theory that the universe is infinite is true, then that would mean that the possibilites of anything to happen are infinite therefore somewhere there must be more humans.
When speaking in terms of evolution, humans are humans because it's what's best in the world that we live in.
In a very similar world, which is likley even if the universe isn't infinite, there may be a species simliar to humans, but there may not be.