XY females:Direct me to one verifiable source that supports what your saying.
So far you've come up with NOTHING except: "uuhh... some people on the internet think so..."
http://en.wikipedia.org/wiki/XY_gonadal_dysgenesis
Do you remember the egg hatching scene from Jurassic Park where they say they make sure all of the dinosaurs are female?
Read the "Pathogenesis" section of the above article. This is what they based this scene from Jurassic Park on.