Female professional athletes are already gender non-conforming. Male ones are still worshiped as exemplars of traditional masculinity. Extremely sporty women have to fight stereotyping that they are lesbians and ignore all manner of unkind commentary about how they are mannish, while sporty men are seen as participating in a form of the masculine ideal.

This is the backdrop to why N.B.A. center Jason Collins' revelations in a Sports Illustrated piece today that he is gay are such a big deal -- and why it is that similar recent revelations from the this year's W.N.B.A. Number 1 draft pick Brittney Griner were greeted in mid-April with a collective yawn.

Women who play professional sports are grown-up versions of what we still to this day call "tomboys," a linguistic relic of our cognitive inability to see outdoorsy, competitive, rough-and-tumble behavior as inherently and naturally female, as well as male. Remember when people were speculating that then Supreme Court-nominee Elena Kagan was a lesbian just because she played on a softball team? "Sorry, softball=lesbian," wrote Brian Moylan in Gawker. (Yeah, that still happens.) Team sports have about them something martial or manly, which means that female team sports are often seen as butch activities. Meanwhile, men who participate in activities like gymnastics or ice skating are often stereotyped as gay; even though they are athletes, they are taking part in something more feminine. As King Kaufman observed in Salon in 2002: "The average American sports fan, watching the Olympic men's figure skating competition, probably figured that most of the contestants were gay." He then went on to debunk this assumption in a conversation with U.S. Olympic medalist Rudy Galindo, "the first actively competing figure skater who was out as being gay."