It is a constant uphill battle for biologists to keep defending the truth that animals have but two sexes, defined by whether they have the reproductive apparatus to produce small, mobile gametes (the males) or large immobile gametes (the females). I’m not going to go into this again as you can read my explanation here. I have a longer and more popular explanation coming out in a big paper in June (stay tuned).
There are just two sexes in animals (and in nearly all vascular plants): male and female. Clownfish are not a third sex (they change from male to female.) Seahorse males are not a third sex (they are males who produce sperm and carry the fertilized eggs of females around in a pouch). Hermaphrodites are not a third sex (they combine aspects of male and female sex), and I’m aware of only one case in which a human hermaphrodite, whose male parts produced sperm, fathered an offspring. Hermaphroditic plants are not a third sex; they are simply hermaphrodites that contain male tissue and female tissue (producing small sperm and big eggs, respectively). There is no individual in animals or vascular plants that produce a third type of gamete. Ergo, sex is binary.
This assertion, accepted for decades by biologists, is offensive to ideological Pecksniffs because they want sex to be a spectrum, as gender is. (Gender and sex are different, and gender really isn’t a spectrum, but bimodal, with the distribution looking like the back of a two-humped camel, with one hump being those identifying as the male gender and the other identifying as the female.)
Under woke ideology, what you think is good in society must be seen as true in nature, an inversion of the “appeal to nature” that argues that something that’s natural is perceived to be good. In this new fallacy, which is still a fallacy, something that’s good is perceived to be natural.
Another example of this fallacy comes from the idea that men and women are behaviorally identical, with any behavioral differences due to socialization. This is of course wrong to anybody with the merest acquaintance of data from evolutionary psychology, hormone differences, parallels from nature, and so on. But if you hold this fallacious idea, then you are not allowed to perceive inborn average biological differences between men and women in their behavior, preferences, or mentaion. And Ceiling Cat forbid the notion that those differences might be partly due to evolution, one result of the much despiséd
field practicum evolutionary psychology.
All of this, and more, is discussed in our forthcoming paper, a masterpiece defending the bastion of known biology against the onslaughts of distortionist ideology. Do I presage this paper to get you interested? Of course, for we had a lot of trouble getting it published since it defends biological truth instead of woke ideology.
But I digress a a bit. Colin Wright, who spends much of his career ably defending the two-sex paradigm against the onslaught of The Elect, has just fought off yet another attempt to argue that sex in humans (and presumably other animals) is a spectrum. Click on the screenshot below to read his piece from the City Journal.
I like the “no” answer, though it should have been larger. In his short article, Wright handily demolishes a deeply misguided preprint (not yet accepted for publication) which maintains that biological sex is “multimodal.” You can find the preprint at the second link below.
Because the sex binary has been so thoroughly stigmatized as inherently “oppressive” and invalidating of transgender and “non-binary” identities and experiences—cardinal sins of our age—this effort has started an arms race among activist scientists to create the least binary model of sex imaginable.
In pursuit of this goal, a “Multimodal Sex literature survey team” composed of researchers from UC–Berkeley and Loyola University Chicago has been assembled to “re-imagine a more inclusive framework for biological sex.” On January 27, 2023, the team produced their first pre-print paper, titled “Multimodal models of animal sex: breaking binaries leads to a better understanding of ecology and evolution.” The paper argues that sex is best viewed as “a constructed category operating at multiple biological levels” rather than bimodal or binary.
In saner times, such a paper would perhaps bring a small chuckle from a journal editor before issuing a swift rejection. But current times are far from sane, and the quick ascendance of fashionable pseudoscience in academia on the biology of sex is ample reason to worry that this paper will not receive the withering review it deserves.
The paper is actually quite amusing when it gives three examples supposedly showing sex in animals is multimodal. Wright dismisses them all handily, handing out the withering review that the paper really does deserve. All three examples actually presume the existence of a sex binary. In a just world, the paper would find a home only in The Journal of Biological Speculations That We Want to be True but Aren’t. But many journals seem to be more interested in what’s politically expedient than what’s true
Colin first re-explains the binary nature of sex When will people ever grasp this? They can’t, just as someone infected with the virus of religious ideology can’t grasp that there’s no empirical evidence for a god, and even if there is a god, he’s either malicious, indolent, or both.
Then Wright dismantles three examples of so-called “multimodal sex”. Here are the first and the third:
The authors then present three “case studies” that they claim demonstrate how the multiple “independent levels of sex” surveyed in the previous sections can be integrated “in a multimodal framework.” Every example intended to undermine the binarity of sex actually reinforces it. For instance, the first case study looks at several “sex role reversed” species that “defy ‘traditional’ expectations of social sex roles,” such as “male competition and female parental care.” But the simple fact that the authors are capable of identifying a system where females and males behave in ways that are not “traditional” demonstrates that being male or female is something entirely separate from possessing behavioral traits like competition or parental care.
Clownfish, like Nemo, not only change their sex roles, but their sexes themselves: when an alpha female dies, one of the males transforms into a biological female, changing its development so that it produces eggs but no longer sperm. It’s not a third sex, but a change of sex. I tell you, I am bloody sick of clownfish and seahorses being touted by the ideological zombies as having a “third sex.” You’ll remember what substance the zombies longed so much for.
Here’s Colin’s third example:
The third and final case study looks at “intrasexual polymorphisms,” which describe differences observed within a sex. “Not all members of the same sex look and behave the same way,” the authors claim, as though this were a novel insight. However, they go on to claim, “Collapsing intrasexual polymorphisms into a female-male binary erases extensive multivariate phenotypic variation.” The very act of referring to these polymorphisms as “intrasexual” means that the sex binary remains.
Not only that, but the sex binary certainly does NOT erase variation in appearance among individuals.
Unfortunately for these ideologues, retaining the real sex binary in animals is what helps make sense of many biological phenomena, like sexual selection and, ultimately, differences in parental roles and behaviors between the sexes. Saying that sex is not binary completely eliminates the value of explaining why, for example, male peacocks are colorful and have long tails, while females are drab and have short tails. (It’s sexual selection, Jake, ultimately based on differences in gamete size.)
Colin wrote a longer version of this critique on his Substack site, Reality’s Last Stand, but you’ll have to be a paying subscriber to read it. It will, however, be released from its paywalled staus in a couple of weeks.
58 thoughts on “The sex binary in animals: a defense by Colin Wright”
Excellent piece of writing – good to know about the longer piece – Oliver S. (I think) put this in an old post and I’m very glad.
The concept on display here, or for the reader to use in interpretation, I think, is parsimony – Occam’s Razor. Wright shows how clarifying this concept is, and how valuable it is.
I am really looking forward to the Promised Paper!
In that preprint the authors do admit there is a gametic definition of sex, and that there are only two gamete types, but they wave this away by pointing to the large number of molecular mating types in fungi and bacteria. They overlook that animal gametes also have diverse molecular mating types that differ in their compatibility with the various mating types of the other sex. Then the authors just pivot to animals, and focus only on non-gamete traits of animal sexes, as if the existence of fungal mating types somehow makes animal gametes irrelevant to the binary nature of the sexes. QEDI, as Jerry says.
The authors also ignore all of the theoretical work by Geoff Parker & others that accounts for the evolution of two gamete types in animals and plants, and can explain why having exactly two gamete types and two sexes might be evolutionarily stable.
Nominated for least justified claim by a scientist: “Nature is a rich tapestry of diversity that affirms, rather than invalidates, human experience.” Nature is no such thing. Just ask Thag.
Yes, that “rich tapestry” includes murder and infanticide (lions and chimps), incest, necrophilia, theft, and just about every one of the seven deadly sins save prostitution.
I’m pretty sure female bonobos practice prostitution.
And I’m pretty sure that prostitution is not, strictly speaking, among the seven deadly sins. It can probably be construed as a subset of “luxuria” – [sexual] lust, which is definitely found in nature.
(On a side note, I am not religious, and I was never Catholic, but the list of the seven deadly sins is not the worst source of inspirations for thinking about morality.)
Speaking of Parker and the distinction between sexes and mating types:
“It is generally assumed (e.g. Maynard Smith 1978, 1982) that ancestrally, gametes were small and isogamous (monomorphic). The evolution of anisogamy (gamete dimorphism) is a crucial transition in evolution (Maynard Smith and Szathmáry, 1995): it represents the evolution of the two sexes, males and females. Following Parker et al. (1972), I favor defining a sex in relation to the type of gamete a sexual phenotype carries. A sex is thus an adult phenotype defined in terms of the size of (haploid) gamete it produces: in an anisogamous population, males produce microgametes and females produce macrogametes. A simultaneous hermaphrodite is thus both male and female simultaneously, and a sequential hermaphrodite transforms sequentially from male to female (or vice versa). This definition of a sex differs from one that defines a sex in terms of gamete mating types (e.g. Wiese, 1981; Hoekstra, 1990). Under the Parker et al. definition of a sex in terms of gamete size, a mating type is not considered to be a sex, but simply a gametic type (that may or may not be related to gamete size) that shows a preference for fusion with certain other gamete types. In isogamous populations, there is thus one sex (though there may be several mating types). Retaining the definition of a sex for an adult phenotype that produces a given gamete size, and a mating type for a gamete phenotype that has a given characteristic for selective fusion may serve to remove some of the confusions that have arisen in the literature.”
(Parker, Geoff A. “The Origin and Maintenance of Two Sexes (Anisogamy), and Their Gamete Sizes by Gamete Competition.” In /The Evolution of Anisogamy: A Fundamental Phenomenon Underlying Sexual Selection/, edited by Tatsuya Togashi and Paul Alan Cox, 17-74. Cambridge: Cambridge University Press, 2011. p. 17)
Do we have any evidence to support the assumption that the first sexual species were isogamous? That assumption might make sense under the assumption that sexual reproduction (meiosis plus syngamy) arose because of the benefits of chromosomal recombination, but relaxing it might make room for other explanations for the origin of sexual reproduction.
My understanding is that the molecular biology of meiosis is shared in common among isogamous and anisogamous eukaryotes, so meiosis is inferred to have evolved first (once). Maybe that’s not correct?
In Parker’s models, anisogamy evolves from isogamy in a species that is already sexual, and is favoured as a solution to the tradeoff between gamete size (and offspring provisioning) vs. gamete number (and opportunities for syngamy under competition with other genotypes).
But I could have misunderstood one or both parts of that argument for why meiosis & sex evolved first in a lineage that was isogamous, followed by the evolution of anisogamy.
I am not able to rattle off references from the literature on this. But I expect the assertion that early sexual species were isogamous rests on the finding that simpler sexual species today are isogamous (small colonial algae, etc). Once you look at slightly more complex multicellular species (like larger colonial protists like Volvox), then *wham* you see eggs and sperm.
Thag’s human experience was invalidated by the spikes on the end of a Stegosaurus tail. I gather that, at least some palaeontologists are quite cross about the thagomiser nomenclature.
I’ve been trying to write a stand-up comedy routine:
“I don’t think I understand this self-identifying gender concept. So if I decide to dress and act in a certain way, I can self-identify as that gender? Is that correct?”
“Now you might be aware that we have a thing in North America called Hallowe’en…”
“So whenever I see one of those ‘What gender do you identify as?’ questions I’m very tempted to put wizard or vampire.”
Call it cynical, but I find “breaking binaries” pure physics envy.
It’s pseudoscience, at least – that isn’t a cynical view…
Actually how the heck can I break anything binary that doesn’t involve a trip to the store to get a new computer?
And “breaking binaries” isn’t the only sign of physics envy. All the emphasis on Theory (in its Critical Race, Gender, Queer, and similar forms) reveals transparent envy of the big unifying concepts in natural science, like the atomic theory, the cell theory, the kinetic theory of gases, the germ theory of disease, etc. etc. Woke verbiage evidently grew out of the intellectual impostures that Sokal and Bricmont demolished a generation ago.
Though “intersectional” might be more mathematics envy.
Or a weird new sort of sofa.
The postreligious intellectual community is becoming quite the rational paradise.
From denial of the sex binary to the drive for an inclusive liturgical language in ecology and evolution, posts like the ones today suggest that we might always have with us those who like their mysticism and meaning, preferably with a heavy helping of power and hierarchy. Inclusively speaking, that is.
From my comments elsewhere:
You could have a really good debate about whether today’s ‘progressives’ favour the Enlightenment or not. I suspect that if the Classic Liberals (in the UK) supported the Enlightenment ideas then the Progressives are a resurgence of contra Enlightenment dark Romanticism.
Wikipedia: “Romanticism was characterized by its emphasis on emotion and individualism, clandestine literature, paganism, idealization of nature, suspicion of science and industrialization, as well as glorification of the past with a strong preference for the medieval rather than the classical. It was partly a reaction to the Industrial Revolution, the social and political norms of the Age of Enlightenment, but also the scientific rationalization of nature.”
I am more inclined to think that the reason why progressives in the 21st century fell into wokeism madness is that the Enlightenment’s views on human nature are seriously inconsistent with the results of biological research, so there are only two results left, the first supports biology And embracing conservatism, the second treats biology as a pseudoscience and actively dismantles social characteristics that conform to the description of evolutionary biology, with the purpose of proving that evolutionary biology is “invalid”, which is the necessity of scientific materialism to kill the value of enlightenment result.
Ideologies that don’t fit the facts have only one path to being eliminated, if most women can only be happy in a conservative environment (dualism, even encouragement of traditional gender roles), then the twentieth century educates women to have late children mocking traditional women’s academics The system is immoral because it makes high IQ women infertile (obviously lowering the potential intelligence of society), men with higher IQs are unable to develop their talents, and it makes people violate their biological behavior sometimes lead to their unhappiness.
The irony is that the conservative social value system of the nineteenth century is more in line with what normal and well-functioning human societies should be like in evolutionary biology. This is why biologists on the left tend to “let wokeism destroy us”, because for them a universe where most women will spontaneously abandon the pursuit of feminist values in favor of conservative gender roles is “evil”, the study On the premise that this universe will only add more misery to life, evolutionary biology is not only evil (because the system designed by evolutionary biology to make most people happy will only tend to be traditional and conservative) but also incompetent (for increase the benefits of society).
Of course, if you can abandon the appeals of Enlightenment and progressivism, and only keep the appeals related to conservatism (excluding the denial of evolution theory in some North American communities), then your thinking will be much smoother.
That won’t fly because conservatives are anti-science regarding creationism and so on. Also, (real) anti-racism made progress because biology showed that most differences between human races are literally only skin deep. And most real scientists are classical liberals.
What I think happened is that in the old days there was so much real suppression of various groups, both those genetically different as well as those who chose an alternate lifestyle, that the default leftist position became to support those groups no matter what. That was capered by people who only claim to be oppressed and once it became clear that they had the support of the woke, the bandwagon started and many jumped on it.
> Under woke ideology, what you think is good in society must be seen as true in nature, an inversion of the “appeal to nature” that argues that something that’s natural is perceived to be good. In this new fallacy, which is still a fallacy, something that’s good is perceived to be natural.
The fallacy you’re looking for here that’s the opposite of the naturalistic fallacy is essentially the moralistic fallacy, which is “when one concludes that something is a particular way because it should be that way” or “when one concludes that something cannot be a particular way because it should not be that way” (definition from https://onlinelibrary.wiley.com/doi/abs/10.1002/9781119165811.ch90).
Well, it’s pretty much the same except that I wanted to refer specifically to things that we see IN NATURE (not including human behavior) only because our ideology prefers those things. Perhaps I should coin a new name for this fallacy.
Ironically, skepticism involving the dangers of transitioning are accused of being the Naturalistic Fallacy. If you think it is better for individuals, including children and teens, to resolve their Gender Dysphoria by becoming comfortable with their sex and accepting of their body — thus avoiding drastic, invasive medical procedures which turn the individual into a patient for life — then you have a magical, unwarranted view that “whatever is natural is inherently good.”
No, you just have a view that performing “drastic, invasive medical procedures which turn the individual into a patient for life” is not always a net good. Which sounds like a very reasonable position to me.
Additionally, ” The moralistic fallacy is often described as the reverse of the is/ought fallacy, wherein one reasons fallaciously that because things are a particular way, they ought to be that way. “
“In this new fallacy, which is still a fallacy, something that’s good is perceived to be natural.”
Can we get an example of that?
The vast majority of crops bear little to no resemblance to their ancestors found in nature.
But if eaten unprocessed and grown without “chemicals”, seem to be considered “natural”.
Yes the definitions are fuzzy (thanks Wholefoods) but only example I could think of.
isn’t that simply the “appeal to nature” – exemplified by the word “Natural” being emblazoned on numerous foodstuff packaging?
where is the [John C above]: “inverse of the “appeal to nature” “?
good -> natural
… that’d be me thinking it is “good” to eat X, so eating X must be “natural”?… sounds weird… especially if it is pineapple on pizza.
[ runs, ducks ]
Thank you, Prof. Coyne and Dr. Wright, for fighting the good fight! Unfortunately, foolishness is cheap and plentyful…
When I see people claiming that there are more than two biological sexes in discussion forums, I often ask what those other sexes are and what role they play in procreation. I have, for some reason, never received an answer…
The motivation to find scientific arguments against the sex binary is, as Wright suggests, a political one — “ to protect or affirm the identities of ‘marginalized communities.’ It’s also a legal one. As it is now, in order to overturn sex-based divisions and protections in law and allow people to use the bathrooms, changing rooms, sports teams etc that match their “gender identity,” two things need to happen.
First, gender identity should be established as an immutable condition present at birth and out of the individual’s control — like race or sexual orientation. And second, the ability to classify people according to sex needs to be put in doubt. After all, feelings about whether one is male or female can only trump the biological condition of actually being male or female if our confidence in this binary is undermined.
Bring in the spectrum. Emphasize intersex. A public school deciding which children use the Boy’s Room or the Girl’s Room based on sex is now unworkable. Asking children which one they are is supposed to look like the more solid alternative.
Would any of these presumably scientific arguments about a sex spectrum in humans have been made absent people identifying as transgender? If the arguments were sound, it seems to me that they would have occurred anyway. I doubt they would have.
At any rate, this essay from Leor Sapir goes into the science-and-law connection much more thoroughly if anyone is interested:
The Lionel Shriver essay someone posted a week ago is very clear on this to.
What’s baffling (and infuriating) is how this ideology became attached to the movement for gay and lesbian rights, where binary sex is very important.
I tell you, I am bloody sick of clownfish and seahorses being touted by the ideological zombies as having a “third sex.” You’ll remember what substance the zombies longed so much for. Brilliant! 😂
Missed that one – nice!
You know I feel patheticly dumb when I ask myself, how do the “ideology zombie” procreate?
By using their heads?
Recruitment agencies like universities?
I kinda feel better now.
I’ll read the paper later for amusement. But from a first skim it looks as though the authors are conflating different processes of biology.
I see references to male ruffs and multiple reproductive morphs but that only reflects diversity in reproductive strategy, not in the nature of biological sex itself. After all, both these examples are displayed by males to “attract” females… (they are both quite fascinating!)
There is indeed an idea of a continuum in the quantitative genetics of sex determination, but that is only related with the shifting of thresholds whether the genetic pathway determines the maleness or femaleness of the individual. Once that threshold is crossed, the individual either develops as male or female or hermaphrodite (there is no third sex). It is a continuum of sex determination mechanisms not a continuum of biological sexes.
Yes! The authors are also conflating what things exists (females or males, which are discrete & binary) with how we can identify and distinguish those things from each other (feminine or masculine traits, which show continuous variation, lots of overlap between sexes, some ambiguous trait values that are consistent with neither sex, and imperfect correlations among different traits).
This is something of a metaphysical question related to why we observe (and therefore distinguish) gametes as large and sessile or small and motile. Could it be because a large gamete contributes its cytoplasm to the new creature, including the genetically precious mitochondria (and chloroplasts in green plants) while the small gamete contributes only its chromosomes? In spermatozoa, the mitochondria that power the flagellum are clustered around its root and are discarded to degenerate as the head of the sperm works its way into the nucleus of the ovum. And all the machinery for protein synthesis and energy generation is provided by the cytoplasm of the large gamete.
I have encountered exasperation at the “reductionist” (a pejorative always being thrown at science) idea that sex should be determined by the size of gametes and not by what the “whole person chooses to be.” To me it makes sense considering what extras, genetic and other, only the large gamete brings to the table.
Most of the definitions of sex I’ve encountered say it’s phenotype — whether the body is organized for the production of large or small gametes. This would mean that an XY individual that couldn’t react to androgen & therefore developed a (nonfunctional) uterus & other female features would be a female.
Depends on whether that XY individual with androgen insensitivity also developed ovaries and ovulated eggs; if not then that person would not be either sex. At least by Parker’s definition (which I share).
That opening list of supposed examples of species that lie outside a sex binary seems particularly useful and called for these years.
“Under woke ideology, what you think is good in society must be seen as true in nature, an inversion of the “appeal to nature” that argues that something that’s natural is perceived to be good. In this new fallacy, which is still a fallacy, something that’s good is perceived to be natural.”
OMG, you’ve distilled it!
I don’t know if we will ever win this in the sense that the opponents will ever concede an inch of ground. This is bc they are ideologues that are immune to facts. But I do like idea of pointing out early and often that their arguments rest on fallacies.
That one’s sex, biology, hormones etc. affect one’s behaviour is certainly true. Do you think you could, however, establish some minimum behaviour patterns that truly characterises the vast majority of males and females? I cannot, and this is why I destroy gender. But you, being an evolutionary biologist, might be able to.
I look forward to your reply. I’m interested what your take might be.
Have a good day.
I am not sure what you’re asking. There are many average behavioral differences between the sexes, some with considerable overlap. Those include aggression, sexual behavior, attentiveness towards infants, and so on. I list many of them in our paper to be published in June. Also, I don’t know what you mean by “minimum behavior patterns”.
But your question is ambiguous: are you looking for IDENTICAL behaviors or differences. For behaviors that both males and females do with equal frequency, try eating, sleeping, and so on.
I think he means some minimum number of behaviour patterns which are significantly different so that one can guess the sex with high certainty. So not just looking at 100 charactertistics and saying “probably male, but not really sure”. The answer is yes. The experiment has been done. An attractive woman approaches a man she knows to be unwatched, says she’s been admiring him, has a van parked outside, and invites him for sex. Same thing with the roles reversed.
I made a second comment explaining what I meant in my original one. (Jerry maybe you can have a look and see if it went unnoticed – feel free to delete the comment I’m making now if that’s the case).
In any case, what I’m basically asking is if there are some minimum behavioural characteristics which are unique to each sex and at the same time very prevalent like the sex characteristics are, which would allow us to use the concept of gender and categorise males and females according to their corresponding gender. I think there are not, which is why I think there are as many genders as there are human beings. But I might have missed something and so I’m wondering if someone else has some data of which I’m not aware of that would support such a classification.
Certainly gender defined via behaviour does differ statistically between men and women but is not nearly as robust as biological characteristics. The experiment mentioned above is an exception, but not a way to classify people in practice. Saying that there are as many genders as there are people makes sense the way you phrase it, but since the term is already used otherwise, it would make more sense to say that it is not a useful concept or perhaps not a useful concept regarding laws or whatever.
I can’t find any other comments you made.
Even if they did have a third sex, clownfish and seahorses are not human. The ability of a clownfish to change sex is no more relevant to human biology than the ability of a clownfish to live under water indefinitely.
There is a term for the insistence that nature reflect the values of one’s social agenda: Lysenkoism. That’s what we should call this.
No, because Lysenkoism refers specifically to agronomy and genetics.
“I favor defining a sex in relation to the type of gamete a sexual phenotype carries. A sex is thus an adult phenotype defined in terms of the size of (haploid) gamete it produces: in an anisogamous population, males produce microgametes and females produce macrogametes.”
(Parker, Geoff A. “The Origin and Maintenance of Two Sexes (Anisogamy), and Their Gamete Sizes by Gamete Competition.” In /The Evolution of Anisogamy: A Fundamental Phenomenon Underlying Sexual Selection/, edited by Tatsuya Togashi and Paul Alan Cox, 17-74. Cambridge: Cambridge University Press, 2011. p. 17)
So far, so good; but the biological situation is actually more complicated when it comes to attributing a sex to individuals that do not yet, no longer, or never produce (and store) microgametes (spermia) or macrogametes (ova) for some reason or other. For example, is a castrated tomcat still male? Is a transsexual woman who has undergone oophorectomy still female? If yes, why?
“[F]emales are equipped to use eggs reproductively and males are equipped to use sperm reproductively.
What if the equipment has been modified or isn’t working well? Is a gelding a male horse? What about men with low sperm counts or beta-males in a wolf pack who will always be prevented from using their sperm reproductively? Which individuals are anomalous or altered or subverted males or females, and which are “other”? Can an individual undergo a change of sex? A durable definition of “male” and “female” will need a little more work before it can yield a clear verdict on every single case. Should the definition allude to the way an organism could function, or is supposed to function, or stick to its actual (past, present, and future) functioning? Whatever we say, the hard cases needn’t threaten the basic idea that, as a matter of plain biology, there are two major sex categories. They don’t threaten the reality of the male-female distinction, any more than teenagers threaten the distinction between children and adults.”
(Kazez, Jean. /The Philosophical Parent: Asking the Hard Questions about Having and Raising Children./ New York: Oxford University Press, 2017. pp. 193-4)
Correspondingly, Paul Griffiths points out that…
“Assigning sexes to pre-reproductive life-history stages involves ‘prospective narration’ – classifying the present in terms of its anticipated future. Assigning sexes to adult stages of non-reproductive castes or non-reproductive individuals is a complex matter whose biological meaning differs from case to case.”
(Griffiths, Paul E. “What are Biological Sexes?” Preprint, 2021.)
Can an individual undergo a change of sex?
No. Not mammals, anyway.
. . .is a castrated tomcat still male? Is a transsexual woman who has undergone oophorectomy still female? If yes, why?
Since you ask, Yes.
There are only two sexes and every mammalian individual is irreversibly one and not the other.* The tomcat started out life as male (having the body plan that makes microgametes) and the woman started out as female (having the body plan that makes macrogametes.) The surgical misfortunes that each underwent did not change them into the other sex. Ergo, the tomcat is still male and the woman is still female no matter than the gonads are gone.
*I’ll exclude individuals with ovotestis (formerly called hermaphroditism) because you didn’t include them in your question.
“There are only two sexes and every mammalian individual is irreversibly one and not the other.” – Leslie MacMillan
Yes, “there are only two sexes”; but, as Paul Griffiths points out (in “What are Biological Sexes?”), “the fact that a species has only two biological sexes does not imply that every member of the species is either male, female or hermaphroditic, or that the sex of every individual organism is clear and determinate.” So despite the nonexistence of a third or fourth kind of biological sex, an individual can be male, female, both, or *neither* (i.e. sexless/asexual).
I’m not saying a castrated tomcat is now female—it isn’t. There is no sex change here, but maybe a *sex loss*. For given the fact that it no longer satisfies the gametic definition of maleness by having lost the ability to make sperm and to use it reproductively, it is anything but “pure pecksniffery” or “petulance” to ask how it can still be justifiably regarded as male rather than as sexless.
I already dealt with this by saying that sexes are defined by the biological equipment they have to produce large mobile or small immobile gametes. To say that a castrated male is no longer a male because his testicles has been removed is pure pecksniffery: a way to either be petulant or to somehow maintain the idea that such a male loses his maleness. Same with women whose ovaries have been removed. I just explained to you, using the definition I have, why such individuals can still be classified as to sex. The biological situation is not complicated at all.
A shame that the actual scientific reasoning you have put forth does not agree with the modern terminology used to shut down reasoned thought, debate, and the Scientific Method of doubt through experimentation.
When Science does not co-oberate “The Science.”
Lets hope the Woke Left does not cancel you too harshly (though we all know they will try).
For those interested, here’s an online lecture by Paul Griffiths on biological sex, in which he also talks about the problem of ascribing a sex to pre-, post-, or non-reproductive individuals (given the gametic definition of sex):