Should transgender individuals play sports according to their biological gender or the gender with which they identify? That's a devilishly difficult question.
There are many potential causes of gender dysphoria, the state of not being psychologically in sync with your biological body. Some of them are due to genetic conditions. Typically, people are born with two sex chromosomes (males are XY and females are XX), but some individuals are born with three. In Klinefelter syndrome -- which may occur in as many as 150 male newborns per 100,000 -- a male is born XXY, and the man will have lower levels of testosterone and other physical and mental abnormalities. Gender dysphoria has also been documented.
In Swyer syndrome, a person has the XY genotype, but the Y chromosome is damaged. (Specifically, there is a mutation in a gene called SRY.) Though the person is genetically male, he develops as a biological female, and the person will actually possess (nonfunctioning) female reproductive organs. Human hermaphrodites also exist, who possess both male and female sex tissues at birth.
These represent just a handful of potential causes of gender dysphoria. Regardless of the precise etiology, inevitably, some people with these or similar conditions will want to become athletes. So who should they compete with, men or women?
The Case of Rachel McKinnon
Rachel McKinnon is a philosophy professor at the College of Charleston. She was born as a biological male and considers herself a trans woman. She also considers herself a world champion in women's cycling -- and likes to brag about it on Twitter. A lot. This did not go over well with many people, particularly female athletes. The 3rd place finisher called the whole thing "NOT fair."
She has a point. While we are not privy to the underlying nature of Dr. McKinnon's transgenderism, a cursory glance at her physique reveals that she is built like a biological male. Regardless of what postmodernists say, there are real, objective, measurable biological differences between men and women. That is why sports are segregated by sex.
But Dr. McKinnon rejects that basic biology. On Twitter, the professor wrote:
(Note: The text was censored for language.)
We have no idea why men outperform women in sports? Wrong. Men are bigger than women. Period. Additionally, men have more muscle mass: Skeletal muscle constitutes about 42% of a man's body mass but only 36% of a woman's body mass. This is literally textbook anatomy & physiology.
Likewise, Dr. McKinnon's claim that the performance gap between men and women in sports being due to sociological differences rather than biological ones is pure rubbish. The reason that the world's fastest male 100-meter sprinter (Usain Bolt) is nearly one full second faster than the world's fastest female sprinter (Florence Griffith-Joyner) is because of biology, not the male patriarchy.
Dr. Kathleen Stock, who identifies as "lesbian not queer" and is also a philosophy professor, didn't take kindly to Dr. McKinnon's boasting. She quite rightly played the science card:
Dr. McKinnon responded by calling Dr. Stock a "transphobic bigot."
Where Do We Go From Here?
As Evita might ask, "Where do we go from here?" It's not practical to create sports leagues just for transgender individuals. Additionally, any one particular biomarker, such as testosterone, is unlikely to be adequate to determine if an athlete should compete with men or women. Instead, a panel of biomarkers -- hormone levels, muscle mass, genetics, etc. -- could be used.
One thing is for certain: Controversies such as this will only proliferate in coming years.