For decades, feminist biologists have insisted that biological sex is a much more complicated matter than a simple distinction between male and female bodies. At the very least, there plenty of people whose bodies fall somewhere in between the strict categories of male and female. At one time, bodies that were neither male nor female were described as hermaphrodites, though that term is derogated within WGS and generally replaced with the term intersex. Intersex is a term used to describe a wide variety of biological situations, but as the video from the Sci Show points out, the term intersex has also been displaced by DSD – Disorders of Sexual Development. The language that we use matters; of special note for this lesson, however, is that the commonly held belief that sex is a naturally occurring binary system is simply not supported by biological observation and current research on sex.
We begin this lesson with a 13 minute video from Sci Show. The host, Hank Green, is not a biologist, but he offers a really great introduction to contemporary scientific views on sexual variance. Although there are some key concepts and terms that you should draw from this resource, the main point to take home is that biological sex is not straightforward; scientists still have a lot to learn about the development of sex—and gender—over time.
As you watch the video lecture, pay attention to the distinctions that Green makes between chromosomal, genetic, and hormonal Differences of Sexual Development, or DSDs. You can test yourself with a short quiz on DSDs in the summary section of this module.

There are More than Two Human Sexes
View Time: 13:40 Minutes
BIG IDEA: Heterosexual Matrix
The heterosexual matrix is an interpretive system that ties together sex, gender, and sexuality. The term is derived from the scholarly work of Adrienne Rich and Judith Butler. We’ll begin with a short podcast.

The Heterosexual Matrix
Listening Time: 8:12 Minutes
The heterosexual matrix looks a bit like this:
The heterosexual matrix does not make room for transgender folks, or masculine women, or feminine men, or folks with DSDs, or non-heterosexual people, or asexual people, or gender fluid people, and the list could go on. What would you add to the list of folks who are not represented by the heterosexual matrix?
Given the matrix’s inability to describe our bodies, identities, and desires in a way that is inclusive of the wide variety of human experience, we need to recognize that it is not a descriptive tool, but a prescriptive one. It provides a simple system into which we are compelled to fit our complex selves. Most notably, the naturalizes normative gender identities and heterosexuality. The term “naturalizes” here means that the matrix functions to make gender identities and heterosexual patterns of sexual desire seem as though they are, they have been, and they will always be, determined by our biological nature.
The heterosexual matrix presumes that the determining factor of our desire and identity is our biology. In this way, it is fundamentally a biological determinist model. What would a social constructionist matrix look like? Something like this:
Instead of emphasizing biology/bodies/sex at the determining factor in identity/gender and desire/sexuality, a social constructionist would look to the other side of the matrix. Adrienne Rich suggests that heterosexuality is not a natural expression tied to our sexed bodies; it is a social system that enables the construction of patriarchal kinship systems. For Rich, the heterosexual matrix is a cultural apparatus that maintains compulsory heterosexuality. Compulsory heterosexuality refers to to the ways that opposite-sex sexual activity and attraction is promoted, encouraged, and enforced.
Whether we imagine the matrix as a system that describes gender and sexuality as natural expressions of our sexed bodies, or we understand that matrix as a cultural system that justifies heterosexuality by making it seem to have biological rather than social origins, the matrix tells a story about how sex, gender, and sexuality, or bodies, identities, and desires are connected to one another. How would you represent the connections between bodies, identities, and desires? How would you represent the connections between your body, your identity, and your desires? Folks like Leslie Feinberg, for whom neither version of the heterosexual matrix makes much sense, promotes a model of gender freedom that looks a bit like this:
Note that in this model, the directional arrows, which represent determinism (or cause and effect relationships) no longer have a function. Instead of having bodies that determine our identities and our desires, in a gender freedom model, we have bodies, we have identities, and we have desires, but the relationship between these things is fluid, open-ended, and never determined in advance.