Here's a thought: Maybe the reason homo sapiens hates and fears homo superior is because they're always messing the spacetime continuum. Because, man, the X-Men sure do a whole lot of alternate reality time travel. How much? Take a look.
Just in time for this weekend's premiere of X-Men: Days of Future Past, Derrick Sanskrit over at The A.V. Club digs deep into the longboxes and plots out the bigger storylines where Marvel's merry mutants have bounced back and forth in time.