It's anthropically necessary that the ontology of our universe permits consciousness, but selection just operates on state machines, and I would guess that self-consciousness is adaptive because of its functional implications. So this is like looking for an evolutionary explanation of why magnetite can become magnetized. Magnetite may be in the brain of birds because it helps them to navigate, and it helps them to navigate because it can be magnetized; but the reason that this substance can be magnetized has to do with physics, not evolution. Similarly, the alleged quantum locus may be there because it has a state-machine structure permitting reflective cognition, and it has that state-machine structure because it's conscious; but it's conscious because of some anthropically necessitated ontological traits of our universe, not because of its useful functions. Evolution elsewhere may have produced unconscious intelligences with brains that only perform classical computations.