Across the U.S., legislators are debating how and when sex and gender should be discussed in the classroom and beyond. Specifically, these bills are considering whether anything beyond male or female can be included in library books and lesson plans. These bills are part of a larger debate on how to define and regulate sex and gender, and there are no immediate answers that satisfy everyone.
Many of the bills draw on science to make claims about sex and gender. For example, Florida House Bill 1069, which legislates pronoun use in schools, assumes that all of a person’s sex markers – listed as sex chromosomes, “naturally occurring” sex hormones and internal and external genitalia at birth – will align as female or male “based on the organization of the body … for a specific reproductive role.” The bill claims that “a person’s sex is an immutable biological trait and that it is false to ascribe to a person a pronoun that does not correspond to such person’s sex.”
Invoking biology is a way to sound objective, but it’s not so simple. Science itself is still grappling with the nature of sex and gender.
My co-author Sam Long and I are high school and college science educators who research how to increase student motivation, interest and retention in biology. Our work and that of our colleagues show that teaching sex and gender more accurately in classrooms benefits not only gender-diverse students but all students and the field of science.
Science of sex and gender
Bills like Florida’s define sex as a binary set of biological traits. But scientists know that sex is far more complicated.
In nature, there is a huge diversity in how sexes are arranged within bodies. For example, the sex of some organisms is classified by the size of their gametes, or sperm and eggs. Some species produce both gametes in one body. Some change whether they produce sperm or eggs over their lifetime. Others technically don’t have a sex at all.
Sex in humans is actually an amalgamation of many traits, which include the type of gametes a person produces as well as their reproductive tract anatomy, hormone levels and secondary sex characteristics like hair growth and chest shape. These traits are determined not just by a few genes on the X and Y chromosomes but also by a myriad of genes on other chromosomes as well as the developmental environment. When many genes contribute to a trait, it appears as a continuum.
The continuum of human sex is illustrated by the experiences of intersex individuals. For nearly two out of every 100 people, a binary definition of sex would not work. People who are intersex don’t have chromosomes, hormones or internal and external genitalia that completely match cultural expectations of what males and females should look like. Under these bills, what pronouns would they be allowed to use? There is no universal scientific rule for pronoun…
