There are no good reasons to doubt that sex is, in fact, binary.
Thank you for this. This is the clearest, most articulate expression I've seen yet of something that we all understand intuitively, but about which many of us find ourselves sputtering when confronted with obviously insane arguments to the contrary (e.g., "Oh, so when you say, 'females can have babies,' you must be saying barren and menopausal women aren't really women because they can't have babies!" and so on).
It must get so tedious to have to keep explaining something. Is their taking apart of the language in service to their ideology or I’m not sure why they choose to change the meanings of words. Puzzling.
Love your papers! Keep up the good work!
Just to add to possibilities for sexual reproduction, Iain M Banks created a species (the Azad) in "Player of Games" with three sexes - males (producing one set of gametes), spices (producing another type) and females (gestate the foetus). If I were to rack my brain, I could probably think of other fascinating thought-experiments scifi authors have come up with!
This is great, however, it seems to have a loophole that my annoying woke friends would exploit.
This is likely going to make you tear your hair out.
> If there’s no disorder... [a male body will produce sperm]. That’s the plan, so to speak. And similarly for females, with regard to ova. That’s all it is to be male or to be female. Simple.
My annoying friends would argue: "Ah, but a transman *would* produce sperm if only his body did not have the tragic dysfunction of female genes and phenotype. Similar argument applies to transwomen and ova. Transwomen are indeed particularly tragic, because it's perfectly possible to be born with XY chromosomes and develop into a fertile woman - alas in their case their bodies did not develop correctly."
(And then there's the mote and bailey: "Nobody's arguing that sex doesn't exist. We just think it's not relevant to gender and gender based sporting categories, like (checks notes) Women's Cage Fighting.)
Love the perspective and the analogy!
This is so great, thank you. Regarding this: "And we’ve also seen that some say things like “sex is not a binary variable,” since there are really four things that can be going on in an organism when it comes to sex: male, female, both, or neither." I have never heard the "sex is not a binary variable" argument, I guess that is connected to what I think of as the Clownfish Argument. Are these people saying that because other individual organisms in nature can be "male, female, both or neither" that an individual human can potentially have that variety of sexual/non-sexual expression? Have real scientists with advanced degrees expressed this? It doesn't make sense to me at all, if you are using the term "sex" to actually mean something.
I don't think it's even theoretically possible for humans to be simultaneous hermaphrodites. Classifying sex as producing one or the other means in humans producing sperm is antithetical to producing eggs and vice versa. The #1 known cause (not STI related) of primary infertility in women is PCOS, which is essentially the ovaries churning out androgens at high levels. This inhibits ovulation or even full maturation of an egg let alone release. The free testosterone level isn't in the same magnitude of male levels unless those males have cancer yet it's still too high to successfully produce eggs. High estrogen in males does the same thing, inhibits sperm production. In the case of ovotestis, if any gamete is produced it's almost always ova, including leading to successful pregnancy, and there are no known cases of both.
I think it would be a stretch to say simultaneous hermaphroditism is even theoretically possible in humans knowing how complex the hormones have to be just for a successful regular production and how those are at complete odds with the other sex's hormones. It's reaching into the bounds of science fiction. Somehow we would have to have two cell types in the same person that are capable of full maturity and then exclude the gonads from the circulating hormones of the person in whose body they reside for the entirety of puberty while at the same time allowing the rest of the body to access the hormones produced by those gonads to complete puberty in order to allow for sexual maturity and development of said gonads.
Isaac Asimov's 1972 novel "The God's Themselves" had an intelligent species in a parallel universe who had three sexes. I haven't read it since it came out, and have forgotten most of the details, but the wikipedia article has a good summary. Asimov well understood that sex denotes a functional role in the act of reproduction and took a lot of care in working out the social consequences of the sex structure, but I don't recall that he had an evolutionary reason for there to be three sexes. What I do recall was that the triple in the story were having a hard time conceiving, and had performance anxiety when they tried to mate. :-)
Not just yeasts...
But as you point out I can be male and female. Which means they are not binary but endpoints on a scale.
Fascinating article, particularly on the history of sexual reproduction and the Placozoa.
However, while there's much that I agree with, notably your emphasis of the centrality of function, I kinda think you've snatched defeat from the jaws of victory by then asserting function really isn't all that essential. Something of a hail-Mary pass that seems characteristic of philosophers writing about the topic.
For instance, see an article by feminist philosopher Holly Lawford-Smith, writing on Medium - from which she was defenestrated for running afoul of the Tranish Inquisition, where she says:
"It’s not as though every male person is such that he actually produces sperm. The best way to understand the ‘sperm or ova’ binary is that it’s true all going well. Of course an individual man could end up with testicular cancer and have to have his testicles removed. Does that mean he’s no longer male? Of course not. He’s the kind of individual who, all going well, produces sperm."
"all going well" 🙄
It's "nice" that she had also argued earlier in her piece that "produces gametes" is the "single necessary condition" for sex category membership. However, she then, in effect, argues that there is some wooish, je ne sais quoi element that leaps into the fray, a philosophical "Deus ex machina", that miraculously rescues such sadly “de-nutted” individuals from the shame and ignominy of no longer qualifying as members of that other exalted category, “males”.
Bit of a murky topic which I certainly haven't "plumbed the depths" of. But I kind of get the impression that function - present, right now, not some time down the road or in the distance past - is often the necessary and sufficient condition for category membership. You might note the definition for sex itself:
"sex (noun): 2) Either of the two main categories (male and female) into which humans and most other living things are divided on the basis of their reproductive functions."
"reproductive functions" - diddly-squat about any "past-present-or-future functionality".
Clocks tell time; that is their essential function, their sine qua non. Rather risible to try arguing that a mechanical "clock" that has had it's mainspring removed, or that has been pounded down into rubble can really still qualify as one. It may LOOK like a clock, may have a passing resemblance to one, and we might say that it WAS a clock, or is one nominally speaking or for reference purposes only. But it no longer exhibits or manifests its essential and defining property.
Kind of think any efforts to disconnect the biological definitions for the sexes from their functional roots is little short of outright Lysenkoism: "the deliberate distortion of scientific facts or theories for purposes that are deemed politically, religiously or socially desirable."
Think you and Colin are basically following in the footsteps of such Lysenkoists, are going down a blind alley by endorsing and promoting what Marco Del Giudice, of the University of New Mexico, called the "patchwork definitions of the [so-called] social sciences":
"On a deeper level, the ‘patchwork’ definition of sex used in the social sciences is purely descriptive and lacks a functional rationale. This contrasts sharply with how the sexes are defined in biology. From a biological standpoint, what distinguishes the males and females of a species is the size of their gametes: males produce [present tense indefinite] small gametes (e.g., sperm), females produce [present tense indefinite] large gametes (e.g., eggs; Kodric-Brown & Brown, 1987)"
No gametes, no reproductive function, no sex.