 And in doing so, they base their beliefs on biological determinism. This is a belief that certain traits are innate and natural to men and women based on their sex assigned at birth. It really advances this narrow idea of gender, doesn't recognize any other gender identity or expression outside of the male-female binary, and it really underlies so much of the sex discrimination that we're fighting today. And today, extremists are relying on that same biological determinism in the context of sports to exclude trans women and girls.