Which sex is the default?

This small topic has taken up a surprising amount of my mental energy over the past few months. It all started when I sat in on a history class called “Women in Sickness and in Health,” which focuses on gender perceptions throughout western history. The first day of class covered the topic of a “default sex.”

In humans, science suggests, it is default to be female. Add testosterone to a person and they begin to show male secondary sex characteristics (deeper voices, facial hair, extra muscles, etc.). Add a Y chromosome to an embryo and you get a male. Though the norm is two, females can have any number of X chromosomes (see “trisomy X”) without ever showing any sign of being male. But so long as someone has a Y chromosome, that person is transformed into something different. 

As a biology major, I was well familiar with these facts. But I wasn’t aware that some people interpreted these results as being sexist. The history class asked, “Can’t we also say that being male is a lack of having two X chromosomes? Or a lack of estrogen? Why are women the ones who are ‘missing’ something? Missing a penis, missing testosterone, missing a Y chromosome, always ‘missing,’ always ‘lesser.'” 

As I mention in the last section, this answer is complicated but mostly “no.” But that’s not what I’m here to talk about. I’m here to talk about “defaults.” Why does equating “female” with “default” mean that they are inferior? In fact, I’m used to the exact opposite: … More Which sex is the default?