The second week of the Olympics is almost upon us, bringing on the athletics competition. Caster Semenya, a talented middle-distance runner, carried the South African flag at the Opening Ceremony of the 2012 London Olympics. The road she travelled to get to this Olympics was a particularly challenging one as not only did she have to qualify, she also had to prove that she was a woman. I've learned two things about gender testing and sport that I found interesting. First, there is no definitive gender test. And second, only women's sport worries about gender testing.