Natural History magazine: Agustín Fuentes rejects the sex binary on ideological grounds, but pretends otherwise

It looks like Natural History magazine has given an implicit endorsement—or at least a platform—to Princeton anthropology professor Agustín Fuentes.  We’ve met him before, and not under pleasant circumstances, as the man is wont to distort science and mislead his readers in the cause of progressive ideology. To see all the pieces I’ve written about him, go here (and especially these pieces here, here, and here.  And for critiques of Fuentes’s misguided accusations that Darwin was a racist who justified and promoted genocide, go here and here, and also see here for one I published in Science with a bunch of evolutionists. Some of these articles show Fuentes deliberately purveying misleading statements to buttress an ideological position. For that seems to be his modus operandi.

Now Fuentes has put his view that sex is not a binary into a new book, an excerpt of which was published in the latest Natural History, a magazine I always liked. This single bad article won’t change my mind about it (as the multiple bad articles in Scientific American did about that rag), but it makes me question the editors’ judgement. Do they know ANY biology? The reason I ask is that the excerpt is so tedious, dreadful, tendentious, misleading, and convoluted that it wouldn’t pass muster in a real scientific journal, and even a scientifically ignorant editor could see the problem with the arguments (and also correct the bad writing).

You can’t go to the article by clicking on the headline; and I don’t have a link, either. I was sent a pdf by a disaffected reader, and that’s what I’ll quote from. Perhaps you can find a copy if you dig around.

The overweening problem with this article is that it doesn’t show that the binary view is wrong, or that biological sex is really a spectrum. What Fuentes does (and he doesn’t really define biological sex) is to show that within the two constructs he take to represent sex, there is a lot of variation in various traits.  Men don’t all behave in a way that differs from the way all women behave, development of sex is complicated, people of different sex have different “lived experiences” (yes, he says that), the structure of families vary among cultures, and so on.

But of course all of this variation, and the multidimensional definition of sex, neglects the big problem: is biological sex binary?  Yes it is: males have reproductive systems that evolved to produce small mobile gametes (sperm) and females have systems evolved to produce larger immobile gametes (eggs). There are only two types of gametes–no more. Biologists have arrived at this definition for two reasons: it’s universal in all animals and plants, and also because of its utility: the different investment in gametes usually leads to differential investment in offspring,  which explains not only sex differences in behavior, but sexual selection itself, which produces sexual dimorphism in appearance and sexual behavior. The exceptions to a strict binary defined (really “recognized”) this way range from about 1/5600 individuals to 1/20,000, and that’s as close to a binary you can get in biology.

What Fuentes does is throw a lot of sand in the reader’s eyes, showing variation within sexes and across cultures, hoping that at the end the reader will say, “Hey, maybe sex isn’t a binary after all.” But that variation does not touch the thesis he’s trying to depose. The man doesn’t know how to debate, so, like a true ideologue, he changes the ground of argumentation.

First (probably in the nonquoted parts of his book), he defines the sexes in an introductory note as “3Gfemales” and “3Gmales”, referring to “typical biological patterns of association between genetics-gonads-genitals in human bodies.” I presume he means that members of each have has the typical chromosomal constitutions of its type (e.g. XX in females) as well as gonads (that presumably means testes vs. ovaries) and genital morphology. Fuentes adds that “while useful as general categories, not all people fit into the 3G classifications.” So that is his definition, and of course since it involves more than gametes, will naturally be less binary than the biological definition. A male with a tiny penis, for example, perhaps because of a disorder of sex determination, would be called a biological male if he has testes, but is something else according to Fuentes. But Fuentes doesn’t say what such an individual is. How many sexes are there? An infinite number? And is that true of raccoons, Drosophila, and robins?

Okay, here comes the sand, so cover your eyes. I’ll have to use screenshots since I can’t copy and paste from this pdf:

Variation in sexual behavior:

But is not “human sexuality” that is the binary, but the definition of sex.  Surely Fuentes recognizes that he is deviating from the main issue his book (and this article) is about: the binary nature of defined sex, as seen in every species of animal and plant. That doesn’t mean that sexuality and its expression is binary.  I’m not sure whether there’s a name for this kind of argumentation, but what he’s doing is clear.

He drags in variation in family structure, too:

Again, all this does is refute a binary of families, not of sexes. Why is it in there? What is the sweating professor trying to say?

Fuentes dwells at length on how sex is basically irrelevant in medicine because sexes show variation in their responses to drugs and get diseases at different rates, implying that the binary is all but useless for doctors. I read my doctor several paragraphs of Fuentes’s screed, and I won’t give his reaction save to say that it was “not positive.” For example, can you even understand this?:

Stable? “Perceived instability”? What is he banging on about? He doesn’t say.

And females are too complicated to deal with in biology, medicine, and health? What is he talking about?  When a patient goes to see a doctor, it’s essential for the doctor to know the patient’s biological sex. Not only are some diseases specific to sexes (prostate cancer, breast cancer) as are some conditions (menopause), but a good doctor will realize that heart disease (and other diseases) can present differently in the sexes, and will investigate further based on that. Females with heart disease, for example, present more often with indigestion-like symptoms than do males. Now of course there are factors other than sex involved in treating a patient (do they drink, smoke, or eat too much?), but saying that sex is pretty much useless when treating patients is simply dumb. It can even be harmful (though he doesn’t say how):

Again, does any doctor pay attention only to sex? I don’t know of one. To be sure, Fuentes grudgingly admits that there are “two sets of reproductive physiologies” that are relevant to medicine, but minimizes the importance of sex. And to be sure, some diseases are recognized and treated identically in males and females, but to ignore biological sex as a doctor is sheer incompetence.

In another example, Fuentes notes that Ambien doesn’t work the way you’d predict in women if you just reduces the male dosage based on a smaller weight of females.  Why doesn’t this work? Because the drug clears from women “3G females” (did the doctors check all the “G”s?) more slowly than from “3G males.”   He uses this difference to attack the sex binary, by saying that we don’t understand why this average difference occurs, saying “asking about the actual physiological response, rather than assuming 3G males and 3G females are different kinds of humans, is a better approach.”

But again, this is irrelevant to the sex binary; it is about the mechanism of a difference between (Fuentes’s) biologicla sexes.  And, interestingly, one of the mechanisms he suggests is “attention should be focused on the varying levels of acting testosterone in attenuating the effectiveness of [Ambien].”

Testosterone! Well at least that has some connection with biological sex, no? Fuentes then tries to efface the difference in hormone levels by saying this:  “Testosterone is not characterizable as a male or female hormone, but rather by variation in circulating levels among humans, with 3G males usually having much higher levels than 3G males.”

In reality, we’ve long known that both testes and ovaries produce testosterone, but the distribution of salivary testosterone in the sexes is indeed variable in each sex, and there is hardly any overlap between the sexes: Since testosterone prompts the development of secondary sex traits, including behavior, it’s the binary nature of sex that produce an almost nonoverlapping distribution of hormones. But one should not imply, as Fuentes does, that variation of hormone levels in each sex means that the sexes themselves are non-binary.

I don’t want to go on much longer, but I’ll add that Fuentes conflates sex and gender several times, and uses familiar tropes to dispel the binary, like the existence of hermaphroditic earthworms, which of course produce only two types of gametes, but in one body. He even shows a photo of a bluehead wrasse, which, like the clownfish (but in the other direction), changes sex in social groups (the head of a group of females is male, but if he dies a female changes sex and becomes the alpha-fish).  And like the clownfish, this doesn’t dispel the sex binary because again, there are only two forms, one producing sperm and one producing eggs. Nobody ever claimed that a biological female can gametically transform into a biological male or vice versa. As always, there are only two reproductive systems, classified by their type of gamete. Neither of these animals produces a third type of gamete.

At the end, Fuentes reprises his error of saying that variation within sexes dispels any notion of a sex binary, and even lapses into philosophisizing:

I love the “why and how humans are in the world.” It’s totally meaningless!  But wait! There’s more: