Simplifying the Complicated Science of Sex & Gender
Between new developments, political lobbying, and real-world consequences, navigating the worlds of sex and gender can be a minefield. Here’s a quick overview to simplify complicated biology.
Much ado has been made about sex and gender over the last decade, as the rise of the Internet has brought together people from all walks of life, packing them into the same digital spaces online and telling them to play nice.
Humans, unfortunately, have a very hard time playing nice.
Fights have erupted over the natures of sex and gender. These online fights eventually flowed over into the real world, where we now have legislative fights over what it means when we discuss biological sex.
There are biological sex fundamentalists who think that biological sex is a binary—you’re either one or the other. They tend to think gender is “all made up” in our own heads. They’ll tell you sex is simple, you’re either male or female, and that’s that.
Then there are the more progressive people who think biological sex is a spectrum corresponding to the vastness of human diversity. Gender is how we conceptualize our sex in a social framework.
Both groups appeal to “science” when they argue.
But whose science?
Science is far from a massive monolith with absolute agreement on everything, which I think is a great place to start. If you’ve been wondering what’s the deal with all this sex and gender talk, I’ll try to simplify it for you the best I can.
Whose Biological Sex, Anyway?
The animals of the animal kingdom are unambiguously honest about their conceptions of sex and gender. They’re so honest, it sometimes shocks us.
The 20th-century essayist Ellen Maloy wrote about her years living among a group of desert bighorn rams she called The Blue Door Band. Far removed from civilization, she observed these animals through binoculars and watched them live out their lives.
She eloquently describes the sexual experience of animals in nature for us:
“Homo sapiens have left themselves few places and scant ways to witness other species in their own world, an estrangement that leaves us hungry and lonely. In this famished state, it is no wonder that when we do finally encounter wild animals, we are quite surprised by the sheer truth of them. Nothing speaks the truth quite like a 220-pound desert bighorn ram mounted atop a standing female, thrusting his heavy pelvis back and forth like there was no tomorrow. It was the rut.
Males, usually solo or in bachelor bands, had joined the females, which for the rest of the year lived separately with random groups of juveniles. The rams were glossy, fat, spirited. Their thick, curled horns and heavy testicles carried a few million years of evolutionary momentum. Here in the canyon, not much else mattered but the bone and muscle needed to transport these body parts. On four hooves rode massive sperm factories.”
This is the nature of sex and biology. On the one hand, our sex cells are how we reproduce; on the other, our bodies are mere vessels to help us replicate our genes.
Ellen Maloy was a writer and environmentalist. She was more of a naturalist philosopher than a scientific disciplinarian. It gave her a keener eye as she observed animals doing what animals do. Science, on the other hand, can sometimes run into problems thanks to specialization.
The Specialization Problem
Part of our public confusion about sex and gender stems from specialization itself.
If you were to ask various scientists in different specialized fields what biological sex is, you’d get radically different answers from each of them.
If you asked a biologist, they would give you an answer resembling the fundamentalist view of biological sex. It would go something like this:
The strict biological definition of sex has everything to do with gametes. Gametes are sex cells. Most animals are asexual. The rest are sexed. All sexed animals have two sexes. The sexes depend on the size of the gametes (the sex cells). The sex with the larger sex cells (eggs) is female. The sex with the smaller sex cells (sperm) is male. There are some hermaphroditic animals capable of being both sexes or changing their sex.
There it is.
A cold, hard binary.
This is the classic textbook definition, and every bit of it is true.
You either have large sex cells or small ones, and nothing else—not even your genitalia—matters.
The problem is biologists focus strictly on biological sex as a means of reproduction. The two driving forces of Darwinian evolution are survival and reproduction. To a biologist, an organism has two goals—to reproduce and create more copies of its genes and to survive long enough to do so.
But this view is rather limited by scientific specialization, just as the others are.
Consider what would happen if we asked an endocrinologist what biological sex is.
We might get an answer like:
Sex is a group of traits that develop thanks to the endocrine system—your hormones—which develop as a result of your chromosomes. Every person is born with either XX or XY chromosomes.
People born with XX chromosomes are female, and they grow breasts and a vagina.
People born with XY chromosomes are male, and they grow penises, markedly more facial hair, testicles, and so forth.
There are people born with chromosomal disorders that make them somewhere in between.
This answer is also correct. It’s both medically and scientifically accurate.
But it’s not a binary.
If you asked a psychologist what sex is, they’d tell you something like:
[Sex is] a person's self-image and mental status as male, female or uncertain. Depending on the circumstances, this determination may be based on the appearance of the external genitalia or on karyotyping.
This is more akin to gender, but it’s also medically and scientifically accurate. I took the quote straight from a medical dictionary.
If you asked an evolutionary biologist, they’ll explain The Red Queen theory to you, telling you that biological sex is how we mix genes to prevent diseases from getting a foothold on us, wiping us out. Genetic variation protects organisms against pathogens.
This is also true. I’ve covered it extensively here.
Now, you’re probably thinking, “Joe, I thought you were going to simplify sex and gender, not make it more complex. What is all this stuff? Do you really expect me to remember all this?”
Of course not.
The big takeaway here is that when people discuss sex and gender and they appeal to science, different scientific disciplines have different conceptions of sex.
Remember that.
Specialized or Vague?
People have spent hours arguing about whether sex is binary. But what’s our definition of sex?
Which discipline and set of guidelines are we using to define our criteria?
When I see people arguing about biological sex and whether or not it’s a binary, I usually see the fundamentalists sticking with the classic biological definition of sex cells as defining factors and progressive people talking about the XX and XY chromosomes, even though both are technically accurate. They just aren’t the whole story.
Even if we put them all together and said:
Biological sex is a series of bodily differences related to how people reproduce. Each organism has either sperm or egg, smaller or larger sex cells. Each person also has either XX or XY chromosomes. Everyone starts off female (eggs)
The problem when we do this is that biological sex becomes the opposite of a “simple” binary. It becomes a complex cloud of overlapping themes, themes painted with the colors of various disciplines, each with its own baggage, that was eventually stitched together by us to construct a vague notion of biological sex.
In short, there is no simple, broad answer to the question because so many different factors go into male-female designations. That doesn’t mean that biological sex doesn’t exist—it surely does—it just means that it’s got a range of traits.
It’s a spectrum.
Non/Binary?
When asking whether or not sex is binary, not only do we need to define what sex is, but we need to define what binary is (apparently). I’m going to borrow an analogy from a book by Melvin Konner, M.D., called Women After All: Sex, Evolution, and the End of Male Supremacy.
If you think that sounds like an angry feminist rant, relax, it’s not. It’s a scientific discourse on the nature of sex and gender in humans and animals.
It’s going to help us visualize sex and gender in a new way that hopefully everyone can understand and agree with. Plus, I made some handy graphics for the visual learners out there.
Stop and imagine we had a long glass tube filled with liquid. On the far end of each side of the tube, we’re going to insert two different colors of dye at the exact same time.
The color red represents the typical “male,” and the color yellow represents the typical “female.”
If we were to put a solid plastic divider in the center of the tube, one that prevents any of the liquid from either side from getting into the other side, and then I put the dyes in, we’d get a binary. The divider would stop any mixing from happening.
This is what a binary looks like. There is one division and two completely different sections. There’s no overlap.
People who adopt the fundamentalist view of biological sex think it looks like this.
They’ve told us for years that sex is a spectrum. But what exactly does that mean?
I think for most people, especially most skeptics of non-binary conceptions of sex and gender, a spectrum looks something like this.
This is what would happen if we removed the center divider and added the dyes on either end, letting the tube sit for about 5 minutes.
Deep red on one end, power-color yellow on the other end, and a slow transition into orange from one to the other. For the skeptics of the gender spectrum, this is hard to believe. Most of the people they encounter are either male or female, and they present as such.
Simply put, we don’t see this much diversity in the sex and gender spectrums in our everyday lives. I think this turns a lot of people off to the idea that sex is a spectrum. It conflicts with our everyday reality.
But what if we tried something else…
Say we took another tube without a divider and repeated this process. Only this time, before we put the dyes in, we pinched the tube in the center. After we put the dyes in, we froze the tube solid so none of the liquid inside could move. We’d get a snapshot of a spectrum that looks something like this.
As we pinched the tube at the center, the two colors would rush to the middle and start to mix. But when we froze it, they wouldn’t have the time to mix completely.
What you’d end up with is two very clear colors, red and yellow, each making up the majority of either side of the tube. But in the middle, you’d have a small minority of liquid that’s a variety of different orange hues, from redder to yellower.
This is an extremely accurate appraisal of the sexual spectrum. It’s not that sex is a binary, nor is it a perfectly blended transition from two polar sides where every conceivable type of sexual expression is equally represented.
Over 90% of the people fit into the categories of male and female, but a small minority will be all sorts of different shades in between, not fitting neatly into either category.
This goes well beyond their mental conceptions of gender. Take androgen insensitivity, for instance. It’s a condition where someone has the XY chromosome pair, but their bodies are incapable of utilizing male sex hormones (androgens) like testosterone.
It’s as biological as diabetes or a broken back.
From MedlinePlus:
Androgen insensitivity syndrome is a condition that affects sexual development before birth and during puberty. People with this condition are genetically male, with one X chromosome and one Y chromosome in each cell. Because their bodies are unable to respond to certain male sex hormones (called androgens), they may have mostly female external sex characteristics or signs of both male and female sexual development.
Complete androgen insensitivity syndrome occurs when the body cannot use androgens at all. People with this form of the condition have the external sex characteristics of females, but do not have a uterus and therefore do not menstruate and are unable to conceive a child (infertile). They are typically raised as females and have a female gender identity. Affected individuals have male internal sex organs (testes) that are undescended, which means they are abnormally located in the pelvis or abdomen. Undescended testes have a small chance of becoming cancerous later in life if they are not surgically removed. People with complete androgen insensitivity syndrome also have sparse or absent hair in the pubic area and under the arms.
Meeting in the Middle
Personally, I’ve seen overzealous activists with political agendas on both sides of this discussion. It’s time we meet in the middle, and we should ignore the loudest voices who seem the least flexible.
Speaking of the middle, what about the people in the center of the tube? Are they just a bunch of purple-haired liberals who secretly believe they’re the opposite sex?
Not quite. The definition of biological sex has shifted significantly since I was a kid.
If all of this sounds crazy, like it contradicts what you’ve learned in school, that’s because, for most people, science’s understanding of sex and gender has advanced since we were in school.
Think about it…
When I was in school, the genome wasn’t even fully sequenced.
We have such a greater depth of genetic understanding now, it’s not even funny.
Here’s a chart from Scientific American that shows all of the various ways biological sex—not gender—can express itself.
It turns out my overview was brief, neglecting many of the nuanced intricacies of sex and gender that we’ve only now come to understand in the past 20 years.
This was intentional. I wanted to offer up a simplified explanation of a complex subject. Hopefully, it did its job of simplifying things for you and explaining the complexity in an easily-digestible way.
One last thing…
We should be cautious about letting science define everything for us. This is especially true with the cold, hard objectivity of biology. Ellen Maloy’s rams have no conception of sex and gender beyond instinct. But they also don’t have sex for pleasure, they don’t write symphonies, and they don’t do a whole lot of other things that humans don’t.
It would make sense that a species that’s flown artificial rockets to outer space might have a much more complex conception and experience of sex than the rest of the species out there.
Sex is more than the body. For humans, sex is meaningful in many more ways than just as an act of reproduction. How many of us are thinking strictly of spreading out our genes when we have sex with someone?
I’m tempted to say no one.
For those who would like the complex version, look no further than these Scientific American articles here and here, which cover different but similar subjects as this article.
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Simplifying complicated things can be helpful. And a lot of your article did that. But too much of it was just simplistic. And that is unhelpful. The science of sex is still in its infancy - in large part because science is never conducted in a vacuum: scientists are raised, and must operate in a world that is filled with religious and cultural taboos about sex. The questions are many and they are important. The answers science has been able to provide so far are interesting, but incomplete. And that is how it should be in any science. It is true in physics where things are more measurable, but even more so in biology, sociology, and anthropology. To draw a parallel: books have been written about how the art of Van Gogh, Gaugin, Lautrec, and some of their contemporaries was influenced by the symptoms they experienced from syphilis (and/or from drinking Absinthe). These are interesting topics to explore. The questions are valid, and the answers may help us gain a better understanding of certain aspects of pathophysiology. They may broaden or deepen our appreciation of these artists and their work. This new knowledge can also lead us to ask more questions. But it can not "explain" their art. Art can be studied, but it can not be explained. The same is true for sex.
Gender, biological sex, sexual drive, reproductive abilities (and evolutionary benefits/challenges), and sexual pleasure and fulfillment, as well as the cultural and societal factors that influence human sexuality are all incredibly interesting. And also incredibly complicated.
I grew up in the Netherlands and lived in red light districts in Arnhem and Amsterdam. I did sex work with men to supplement my income during my college days in the 1980s and 1990s, and then worked as a clinician in HIV, STD, and Infectious Disease for the remainder of my career (I retired last month). Working in poor inner city neighborhoods, rural areas, prisons and jails, and later also in various countries in Africa has taught me lot about human sexuality. Sometimes I felt that Oscar Wilde was right when he said: "Everything in the world is about sex except sex. Sex is about power." But even that is too simplistic.
Everything about sex is complicated. And fascinating. I know you share that view and I look forward to reading your next piece!