I read this paper:
Bachtrog D, Mank JE, Peichel CL, Kirkpatrick M, Otto SP, Ashman TL, Hahn MW, Kitano J, Mayrose I, Ming R, Perrin N, Ross L, Valenzuela N, Vamosi JC (2014) Sex determination: why so many ways of doing it? PLoS Biol. 12(7):e1001899.
And now I give you a quick summary of a couple of figures that I know you’ll find useful if you’re teaching genetics.