There was an 800-meter women’s race today in Berlin that has people talking. The question: Is the winner Caster Semenya male or female? Here’s the race, which starts at the 3:00 point if you want to skip the preliminaries:

Here’s a discussion with Michael Johnson after the race:

As he points out, there is no cheering after the race.

So how do officials decide if Caster Semenya is male or female? As this article points out, it is a lot more involved than having Caster drop her pants:

IAAF asks South Africa to conduct gender verification test on rising track star Caster Semenya

scientists are likely working on a sample of cellular matter donated by the athlete through a cheek swab, and are looking at chromosomal and hormonal patterns. According to sport bylaws, reports are drawn up by a panel that includes an endocrinologist, a psychologist, and others.

Here is a description of the X and Y sex chromosomes:

But it is somewhat more complicated than that, as explained in the following documentary:

Are we on the cusp of discovering what determines gender? The old mantra – all girls have XX chromosomes and all boys have XY – is no longer reliable. Scientists are now looking beyond chromosomes to “brain sex” and the role of newly discovered genes. By studying transsexuals and people on the gender extremes, they believe they can unlock the gender puzzle. This high-quality documentary looks at the new and challenging science of gender.

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