Sex is a spectrum

Agustín Fuentes has published a new book, Sex is a Spectrum: The Biological Limits of the Binary. I just started reading it last night — and it’s very good so far — so don’t expect a full review just yet, but El Pais has published an interview with Fuentes in which he discusses the main themes. As you might guess from the title, he’s rejecting the idea that sex is a binary, and further, that the general implications of sex are not reducible. He’s an anti-Coyne. He’s also strongly advocating for a view of organisms that incorporates environmental factors beyond naked genetics.

Q. You assert that sex is a biocultural issue… but many of the people reading this interview will think that sex is about biology, not culture.

A. That depends on how you define “sex.” If you’re speaking only about gametes, everyone understands that [an] egg isn’t a woman and [a] sperm isn’t a man. We have to rethink a little about what we’re talking about. Just think about our feet, which are biological traits. But at the same time, look at your foot and look at the foot of a person who has never worn shoes. The two are almost distinct: the structure of the bones, the muscles and the skin changes. When I discuss sociocultural contexts, we’re talking not only about the embodiment of culture, but the mutual exchanges between experience, perception, bones, muscles, digestive systems, vascular systems… there’s a lot of interconnection between our physical body and the world and the experiences we have. There’s always more intermingling and a bit more complexity.

One of the unfortunate consequences of the Mendelian revelation is that we’ve swung way too far the other way, treating the individual as nothing more than the combinatorial action of a set of genes. Development is a critical and complicated input in generating the information that makes up the individual!

Then he gets into a point I’ve made multiple times before: there are so many distinct criteria that are used to identify a human’s sex, so just the fact that there are multiple independent measures refutes the claim that there is one pure definitive definition.

Q. You write about how the concept of “sex at birth” isn’t very rigorous, because it can mean many different things. You talk about the “three Gs.”

A. In the biological context, we’re talking about typical categorizations based on three factors: genes, gonads and genitals: the three Gs. A 3G woman would be one who has ovaries, clitoris/vagina/labia, and XX chromosomes. And a 3G man would be one who has testicles, penis/scrotum and XY chromosomes.

The importance of using 3G is the range of variation: it’s a spectrum that has standard groupings. We assume that, by looking at the genitals, you’re sure to have the other two Gs. And it’s true that they’re highly correlated, but not absolutely correlated, not 100%. We must understand, biologically, that these categories don’t contain all the variation in human beings; there’s variation beyond that. And, among the 3Gs, there are people – more than we think – in whom one of those Gs is a little different. If we use only the genitals at birth, or the chromosomes or the genes, we’re leaving out a lot of extremely relevant information.

I agree, except I’d suggest that there are more than three factors used. Some people claim that behavior is a factor in defining sex — true women, as we all know, are submissive, while men are dominant and aggressive. We can pile up all sorts of stereotypes and associations and none of them are going to be universal.

Q. This 3G explanation doesn’t reflect the biological reality of 1% of humanity, as you state in the book, which is at least 80 million people. But if it reflects that of the 99%, so isn’t it natural for many people to say, “Well, 99% is almost binary, isn’t it?”

A. But what is binary? I’m not saying there aren’t things that are binary in human beings. Gametes are binary: sperm and eggs. But saying that human beings are binary is a failure. It limits us too much when we’re thinking about the full range of variation between human beings. A binary relationship is that of one and zero. They’re completely distinct. This concept is used in computer science, because there’s no overlap in any element: either you have a one, or you have a zero. But human beings – our bodies, our ways of being – aren’t like that. There’s nothing between men and women that makes them totally different, like one and zero, because they come from biological materials that overlap on that spectrum of variation in our bodies.

To say that we’re binary is philosophy. It’s not biology. It’s declaring oneself essentialist: there are [men and women], two types of humans. But our biology doesn’t validate that position. Yes, there are binary things in our biology, but to say that human beings come in two different types is false. And we can prove it. Genitals, hormones, brains, organs… when you understand the range of variation between our bodies, it becomes very clear that human beings don’t come in binary, but in typical sets.

“Almost binary” — how can anyone say that with a straight face? The word “almost” refutes the claim.

Q. Is this an attempt to invoke science to justify a model for people? A model for society and a model for women?

A. Trump isn’t using science; all of his executive orders are a total scientific failure. Science – by pointing out the range of biological variation in human beings – shows us that there are indeed several ways to be human. And that’s the important thing. In any country, in any culture, there’s a range in bodies and sexualities, but our cultures, our governments, diminish the possibilities of expressing [ourselves] and living within that range. We’re always on an average; we’re bits and pieces of the full range of human beings. And the main thing is to at least know what the possibilities of that range are… to understand that this is what being human is all about: variation, not a standard.

Our culture is always controlling where we can express ourselves. We’re biocultural organisms: there’s always a greater range of variation than what’s culturally accepted. And that’s the difficult part. Because many people are certain that “this is a woman and this is a man.” But if they start thinking, “My cousin has a slightly different body,” they then realize that there’s greater variation. We all know people who are outside the typical categorization, be it behaviorally or biologically, of what we think women and men are.

Wait — he didn’t answer the question! Should we have a different model for society, men, and women? I’d say yes, and I can see how Fuentes is addressing an implied point, by bringing up Trump’s anti-scientific attempts to impose a rigid binary structure on America. It is the scientist’s role to explain how our preconceptions about the universe are contradicted by nature, and the narrow perspective of conservatives is flatly wrong, and therefore is a bad foundation for building social policy.

Fuentes for president! He’s American-born, so he qualifies, but he “wants to regain Spanish citizenship for fear of the political degradation in the United States,” so I’d worry that he’s going to be part of the flight of intellectuals from the US.

I expect I’ll see her at CPAC next

I wasn’t mad at Sydney Sweeney before — she was just a dumbass ignorant of genetics and making a commercial for money — but now she has lost all benefit of the doubt. She is a registered Republican.

Richard Hanania, who wrote for white supremacist news outlets under a pseudonym before becoming an above-board conservative columnist, took credit for Sweeney’s affiliation.

“It’s been revealed that Sydney Sweeney has been a registered Republican since June 2024, just a few months after I set off the discourse about her being the end of woke,” he wrote on X. “It looks like I memed into reality the biggest Republican celebrity recruit in years.”

I can’t say she was much of a draw for me before, but now I’ll be even more unenthused about her work. I’ll just visualize Jon Voight in her roles.

Three boys

Don and me as toddlers, from this video

By luck, my mother and my aunts gave birth to three boys of roughly the same age: me and my cousins, Kelly and Don. Furthermore, they had second children who were all boys, my brother Jim to run with me, Matt to go with Kelly, and Tim with Don. When we got together as a family, that meant we had a built-in gang of 6 boys, and the adults could get us out of their hair by telling us to run off and do boy things. Catch garter snakes and frogs. Curl up and read a ragged box full of comic books. Go for a hike. Gather sticks to use as swords. Climb trees. Boys are predictable and controllable, to a point, and we were happy to run wild.

We weren’t all the same, though. I was the weakest of the bunch, a nerd who preferred the comic book option. Kelly was the wild child, the one who always had a pocket knife, who wanted to set things on fire, who sneered at the wimpy egghead, and who’d usually end up wrestling me to the ground to prove that he was the most macho. He was a piece of barbed wire with a leather handle. Don, on the other hand, was the actual big guy among us — Kelly didn’t pick fights with him — and was solid, secure, and reliably peaceable, an oak tree supporting his friends and family.

An anecdote told to me by my Uncle Ed:

Ed: “One of the cousins carved your name into the furniture in my room.”

Me: “It wasn’t me!”

Ed: “I know. You aren’t dumb enough to sign your vandalism, and Don would never try to get someone in trouble that way, so I know exactly who was responsible.”

Later, when I actually saw the carving, I discovered that they had misspelled my first name. It’s only four letters long!

Only ten years old, and we already had the personalities that would shape the rest of our lives. As you know, I grew up to be a teacher and biologist. Sadly, Kelly became even more of a trouble-maker, had a few run-ins with the law, and ended up dying of a heart attack, alone in an isolated house in Eastern Washington. Don became a Mormon, married a good Mormon woman, raised a family on a farm in Oregon, and was a pillar of his church and his community. He retired to Arizona, and lately was working to move his elderly mother to live near him so he could better take care of her. All of that was typical Don.

Yesterday I got a phone call to let me know that Don had abruptly died of a heart attack.

Now I don’t know what his mother, my Aunt Sally, is going to do. The reliable anchor of his family is no more. I’m waiting for a phone call with more news.

The gang of 6 boys is over (two of our brothers have also died), not that we were getting together regularly to cause trouble. It was reassuring to know that Don was was still solid and reliable, and now that is gone.

An almost day

I hobbled into the lab this morning, anticipating a lot of spiderlings that would need to be sorted out. I’ve got several egg sacs dancing on the edge of maturity, and I’d noticed on Friday that one of the Steatoda borealis sacs was really close — maturing spiders were darkening and moving about just below the surface of the sac, so I expected to come in today and find an explosion of spiderlings scurrying about looking for something to kill.

I was disappointed. They haven’t quite emerged.

See the dark mottled blob on the top left? The dark things are spiderlings clinging together in a ball, with the bounds of the disintegrating sphere of the sac. The white things are the final molt, that leaves behind a crumpled bit of cuticle. But they aren’t out yet!

Also in view is a second egg sac which isn’t quite as far along. I can tell by the somewhat granular appearance of the contents that the embryos are developing just fine, maybe a week or two behind their older siblings.

Mom is also there, a bit out of focus. These spiders are very good mothers, hovering over the egg sac and fighting anything that comes along to disturb her babies. Also, they do the greatest kindest action — they do not eat their own children when they emerge, no matter how juicy and tasty they look. I expect there has to be a swarm either tomorrow or Tuesday.

Also I got a little treat: my tarantula, Blue, usually hunkers down in her hidey hole, but every once in a while she emerges to explore her big cage. Here she is, just before I rewarded her with a mealworm.

I can do arachnomancy, too

Everybody and their mother has been sending me links to this story, Spider divination. In Cameroon, they have a practice of cluttering up a spider’s burrow with leaves and sticks and stones, and then interpreting the future from how it tidies up the garbage.

Questioning a spider involves first clearing the area around its burrow. Then a large, open pot that has had its base removed is placed over the hole, with a piece of tin used as a lid. The pot and tin keep the spider in a contained space. A stick and stone are left inside, with special marked leaves (which I think of as ‘cards’) placed over the hole. The diviner then asks a question in a yes/no (or either/or) format – with each response corresponding to either the stick or stone – while tapping the enclosure to encourage the spider to emerge from their hole. The stick and stone represent possible answers, while the leaf cards offer the possibility of further clarification.

My tarantula, Blue, likes to hide in a silk covered tent she has constructed — when I look in, all I usually see is a dark hole with maybe a couple of legs visible in the shadows. I leave her meals in a space in front of the opening, and she will dart out and the prey disappears. She is very tidy, keeping her silk-lined floor clean, so could see using standard spider behavior as an indicator of the state of the universe.

Blue is back in the lab, but I have an oracle right here in my home. She lives in the corner by our internet router, and has strung silk around all the various cables. I trust that she has far more access to information than a spider in a hole in a remote Cameroon village. Here she is:

She is very pretty, so you know you can trust her. I asked her whether these spiders are a good source of information.

“Of course,” she told me, “this is a historic, traditional mode for getting input from spiders, a variation of the technique you are using to communicate with me — I’m just a bit more articulate. However, you have to read deeper into the article to see the truth. Read this paragraph.”

In many forms of divination, randomness is important. Examples include bibliomancy (opening a holy text and picking a verse at random), tarot and other sorts of cartomancy (shuffling the cards and picking some at random), Yijing and Ifá (throwing coins or chains; picking up odd or even numbers of sticks or nuts), or African basket divination in which objects placed in a basket are repeatedly tossed in the air (those that settle on top are then interpreted to answer a question). The point of this randomness is that the diviner cannot influence the result, so the message from beyond can be heard without the risk of human manipulation and interference.

She continued, “They are using the spider as a random pattern generator. The author fails to understand the key to the author’s misunderstanding, though, is that final sentence, ‘The point of this randomness is that the diviner cannot influence the result,’ which is false, and gives the game away. The diviner has all the power here as the interpreter of the pattern. The spider can be howling that the answer is X, but the interpreter can then declare that the answer is Y. The author is an unreliable source if they are able to ignore the power of the human manipulator of information.”

“By the way, PZ, I expect you to report my explanation accurately and completely, or my children will build nests in all of your orifices while you sleep.”

She really didn’t have to threaten me — of course I would avoid manipulating or interfering with her truth — but I could tell that she was annoyed by this story about humans stealing the authority of spider-kind for their own selfish ends.

Kent-Meridian High School Class of 1975 50th Reunion!

One of the lesser phenomena of the summer is the blossoming of high school reunions. Remember high school? Or are you trying to forget it? I’ve been contacted by one of these companies that hosts online sentimentality about being 18 years old, and tries to organize these events where old classmates get together awkwardly to shuffle their feet and try to have conversation with people they used to be forced to share a room with lots of desks with, and try to reconnect and figure out what the heck everyone is up to now. That could be fun, I’m sure my peers have gone off in all kinds of interesting directions and I wouldn’t mind catching up.

The pressure is particularly high this year because it’s been 50 years. I graduated from Kent-Meridian High School, out there in western Washington state, in 1975, and that’s a nice round number, so of course we have to have a party. Unfortunately, I’m not motivated enough to fly 1500 miles to meet with people I’ve grown away from for so long. Why are we even doing in-person meetings for this purpose when we have technology that would allow us to have those conversations online?

Then I saw that there are two separate reunion events for my class this week. I realized that there are no central organizing principles behind these events — it’s just people stepping forward to host little parties called “reunions”. Hey! I can do that! So I’m creating an online event (like they ought to be) to talk about high school. Everyone is invited!

There are a few obstacles to doing this. I live 1500 miles away from my old high school, and I have no ongoing connections to my former peers. Also, to be fair, I was never one of the popular kids, and I suspect that most of my ex-classmates would say “who?” if my name were mentioned to them. It’s rather bold for one of the uncool, most forgettable students in the class of ’75 to have the affrontery to host a reunion event. I’m doing it anyway. I’m opening the virtual door to anyone who wants to show up and say, “you haven’t changed a bit, man” to some old guy and tell him about your used car lot/insurance business and hand out business cards.

I don’t care if you are a Kent-Meridian alumnus, or when you graduated, or even if you graduated at all. We can have a conversation about standards of public education, or popular ’70s music (we can be sad together about Ozzie Osbourne), or reminisce about antiquity, or whatever. Pester me about anything.

I don’t expect anyone from my high school to show up, and that’s OK.

(It’s really an excuse for a live stream.)

I’m not mad at Sydney Sweeney. I’m just disappointed that this is the only genetics education most people will get

Sydney Sweeney has an ad for American Eagle, in which she simply buttons up a pair of genes in, I guess, a sultry way, while delivering a genetics lesson. It’s kind of a half-assed lesson.

Genes are passed down from parents to offspring, often determining traits like hair color, personality and even eye color.

OK, but it implies a simplistic pattern of inheritance, and worse, uses the word “determining”. “Affects,” or “modulates,” or “contributes to” would be better — there are at least 16 critical genes behind eye color, with maybe 150 genes that can effect the expression of color. Eugenicists a century ago tried to claim that that it was regulated by a simple Mendelian dominant/recessive relationship of a few alleles, but that idea fell apart pretty fast. All you have to do is look at the range of colors in the human population to see it can’t be that simple. Anyone who has a basic understanding of genetics is going to see the flaws in that line.

I’m not going to try to guess how many genes are involved in “personality.” All of them? With a huge contribution from environment and experience.

But then the ad company makes it even worse.

“My jeans are blue,” Sweeney concludes, with the ad delivering the now-infamous line, “Sydney Sweeney has ‘good jeans.’”

Oh god, are they like 12? Conflating ‘jeans’ with ‘genes’ is one of the oldest ‘jokes’ around — I teach genetics, and that word game is so tired and weak, especially since there aren’t even any good jokes built around it (if you know of any, tell me in the comments and I’ll judge the quality of your humor.) I groaned when I heard it. It doesn’t even rise to the level of a dad joke.

This, I thought, is the level of understanding the American public has of genetics.

I guess when I teach genetics this Spring I’m going to have to flop down on the floor with my shirt unbuttoned and slowly fasten up my pants. That’ll get their attention.