Evolutionary psychology (EP) proposes that brain and cognitive structure, like physiological structure, has been designed by natural selection to serve survival and reproduction.
Sex and gender minorities pose a special dilemma for evolutionary psychology: we muddle what they see as clear formulas regarding reproduction and sex differentiation.
If you think about gender variance as a value that eludes full human understanding within a scientific language, like pi in mathematics, gender diversity exposes the limitations in EP’s system of representation. Rather than appreciating and understanding the elegance and intricacy of this mysterious value of gender variance, an evolutionary psychologist named J. Michael Bailey has suggested we essentially round pi to a nice easy-to-understand integer by saying there are two sexes and rounding off the little fractions of sex and gender minorities to make the other equations easier.
He does this by claiming there are two, and only two “types” of trans women: extremely gay men and straight men with a fetish.
This simplistic definition allows for an easy answer to the problem we pose for EP. Of course, this model is worthless given existing and upcoming reproductive technologies that bypass natural selection.
Nonetheless, Bailey insists his model is correct, since conceding it isn’t opens up a huge flaw in his worldview and his hypothesis. In his world, it is very important that gay/straight and male/female binaries be defended and justified.
This of course leads to fundamentally flawed results from calculations with this rounded number, but that hasn’t stopped him from a vigorous defense of his decision to simplify humanity to a Mendelian quadrant of XX/XY.
In the EP worldview, transsexuals are”evolutionary mistakes” (as J. Michael Bailey calls it), or perhaps more generously an evolutionary paradox: why does a trait that leads to fewer offspring persist?
I’ll have much more to say on this matter in the future, but evolutionary psychology is a very attractive field of inquiry to eugenicists and others who believe that all humans are not equal, and that many are in fact unfit or maladaptive. These people who measure human worth by intelligence or reproductive capacity are the leading edge of the upcoming bioethical battle regarding variance of all sorts, from genetics to gender.
Other resources:
Wikipedia entry on evolutionary psychology
Other evolutionary psychologists connected to the Bailey debate: