On February 6 of this year, the Presidents of three evolution/ecology societies (the Society for the Study of Evolution [SSE], the American Society of Naturalists [ASN], and the Society of Systematic Biologists [SSB]) put a letter on the SSE website. It was a reaction to a Trump executive order about the definition of sex, and the “tri-societies” statement asserted that sex is not binary (in ANY species), but was a multidimensional multifactoral “biological construct”. I archived the letter here because I had a feeling that it would cause trouble.
It did. But first, read it below. It was written, of course, as a kind of virtue-flaunting exercise to placate those who don’t feel that they are either “male” or “female” (“nonbinary” people). But in so doing, the three Societies promulgated a gross distortion of what many (I won’t say “most”, since I don’t know) biologists conceive of as the definition of sex, which is based on gamete size and is close to being binary as it comes. I’ve bolded bits of it below, bits that conflate sex and gender, throw in “lived experience” to add to the confusion, and claim that the nonbimodality of sex “is a hallmark of biological species,” implying that in all animals and plants the definition of sex is far more than bimodal.
Note that the members of these three societies were not polled about the so-called “scientific consensus” they assert; this is a diktat from the Presidents. Voilà: the original “tri-societies” letter:
President Donald J Trump
Washington, DCMembers of the US Congress Washington, DCFebruary 5, 2025RE: Scientific Understanding of Sex and GenderDear President Trump and Members of the US Congress,
As scientists, we write to express our concerns about the Executive Order “Defending Women From Gender Ideology Extremism And Restoring Biological Truth To The Federal Government”. That Order states first, that “there are two sexes…[which] are not changeable”. The Order goes on to state that sex is determined at conception and is based on the size of the gamete that the resulting individual will produce. These statements are contradicted by extensive scientific evidence.
Scientific consensus defines sex in humans as a biological construct that relies on a combination of chromosomes, hormonal balances, and the resulting expression of gonads, external genitalia and secondary sex characteristics. There is variation in all these biological attributes that make up sex. Accordingly, sex (and gendered expression) is not a binary trait. While some aspects of sex are bimodal, variation along the continuum of male to female is well documented in humans through hundreds of scientific articles. Such variation is observed at both the genetic level and at the individual level (including hormone levels, secondary sexual characteristics, as well as genital morphology). Beyond the incorrect claim that science backs up a simple binary definition of sex, the lived experience of people clearly demonstrates that the genetic composition at conception does not define one’s identity. Rather, sex and gender result from the interplay of genetics and environment. Such diversity is a hallmark of biological species, including humans.
We note that you state that “Basing Federal policy on truth is critical to scientific inquiry, public safety, morale and trust in the government itself”. We agree with this statement. However, the claim that the definition of sex and the exclusion of gender identity is based on the best available science is false. Our three scientific societies represent over 3500 scientists, many of whom are experts on the variability that is found in sexual expression throughout the plant and animal kingdoms. More information explaining why sex lies along a continuum can be found here. If you wish to speak to one of our scientists, please contact any of the societies listed below.
Carol Boggs, PhD
President
Society for the Study of Evolution
president@evolutionsociety.orgDaniel Bolnick, PhD
President
American Society of NaturalistsJessica Ware, PhD
President
Society of Systematic Biologists
president@systematicbiologists.org
You can see all my posts about the resulting kerfuffle here. In short, intiially about twenty of us wrote to the three societies objecting to the letter’s scientific contentions. Eventually 125 people connected with evolution appended their names to the letter and were willing to make their objections public (see here). Richard Dawkins also got into the fray, and both he and I discovered independently that the three Presidents who signed the letter actually act as if sex were binary in their own published research. Further, two former Presidents of the SSE also publicly disagreed with the characterization of biological sex given above.
Finally, our letter signed by 125 people asked for an answer, and although we got one from the societies, we were also told we couldn’t make it public. So be it, but I did characterize the answer here, and the societies largely conceded our points. As I wrote:
. . . . this time we asked for a response and got one, signed by all three Presidents. I can’t reprint it because we didn’t ask for permission [we later did but were refused], but some of its gist is in the response below from Luana [Maroja]. I will say that they admitted that they think they’re in close agreement with us (I am not so sure!), that their letter wasn’t properly phrased, that some of our differences come from different semantic interpretations of words like “binary” and “continuum”(nope), and that they didn’t send the letter anyway because a federal judge changed the Executive Order on sex (this didn’t affect our criticisms). At any rate, the tri-societies letter is on hold because the organizations are now concerned with more serious threats from the Trump Administration, like science funding.
It’s still on hold, but now they’ve taken it down (see below).
I closed my post this way:
I end by saying that scientific societies need not be “institutionally neutral” when they are dealing with issues that affect the mission of the societies, as the definition of sex surely does. But what’s not okay is for the societies to distort “scientific consensus” in the interest of ideology. I have no idea if the Presidents of these societies really believe what they said (as Dawkins has pointed out, all three Presidents use a binary notion of sex in their own biological work), but something is deeply wrong when you use one notion of sex in your own science and yet deny that notion when you’re telling politicians what scientists “really believe.”
It’s just wrong when three evolution societies give the public a distorted view of how biologists define “sex”, and even more wrong when they do so because they are motivated not by the search for truth but to cater to a certain ideology.
As this sad drama draws to an end, I was just informed that, after several months, the three societies have taken down their misguided diktat. Go to this SSE website and you’ll see this note:
As they say, “a revised version is in progress and will be posted shortly.” I look forward to the revised definition of sex! I also note that, as far as I know, no members of the three Societies have been informed that the letter was removed (they were told that the letter was posted, but only several weeks after it went up).
I’m posting this simply as a public service, to inform members of the Societies, and others following kerfuffles about the definition of sex, that the letter was finally taken down and will be replaced. The silver lining is that although I found the original letter embarrassing to science–and just another reason for people not to trust science–the Societies are rethinking what they say about sex. However, I doubt that the replacement letter is going to emphasize the bimodality of sex as it is defined by many biologists. After all, the Societies have to be ideologically correct, don’t they?
h/t: Luana Maroja (who did nearly all the heavy lifting of writing responses, gathering signatures, and so on.
If I had to guess I’d say the new version of the letter will struggle mightily to both admit that sex is binary but make room for trans activists to claim that “the science is on our side.” I’d expect equal parts of nature-is-varied, nature-isn’t-sharply-divided, and science-doesn’t-come-into-conflict-with-new-cultural-ways-of-categorizing-sexandgender.
Yeah, that’s pretty much what I expected, too. But I expect even more that they are simply not going to replace the letter with anything. Not doing so is the safest way to avoid ridicule!
Yup. If you dislike being thought of as a clown, stop throwing pies.
It would be simplest if people would simply use the word “sex” in it’s original biological meaning and stop using “gender” as a synonym.
I agree 100% with you on this.
Thank you for keeping us updated. How ridiculous! How craven these societal heads are.
I very much dislike this whole thing.
I dislike that statements from the medical field and from some scientific societies are that evolved biological sex is a social construct that lies on a continuum. All motivated by a well meaning but incorrect ideology.
I dislike that it takes a dangerous and decidedly anti-science administration to persuade these spokespersons to start walking back their ill-considered claims. I think this removal of the letter is motivated by a concern about the current political climate. Ideology versus ideology.
I dislike that the course correction from the Tri-societies is not because they realize their errors in facts. No, they withdrew the letter because their ideology isn’t as dangerous as that other ideology.
Mark I agree with you. My only quibble is that, while I expect Boggs, Bolnick, and Ware are themselves well-meaning as individuals, I think the ideology itself is anything but.
Completely agree. And the battle of ideological bullies is currently not going their way.
Not “well-meaning” in either case.
Congratulations on your success. At least the Supreme Court here on the UK didn’t balk at this. The fact that the verdict was unanminous was quite telling.
All credit to the UK Supremes, but their decision had zero to do with the facts about sex etc. and everything to do with the intent of the parliament that passed the Human Rights Act. Nothing prevents the current parliament from passing an amended Act defining “sex” away from biological sex and towards metaphysical gender; which the Court would then use for subsequent decisions. IANAL.
Sex characteristics are on a spectrum, biological sex isn’t.
My school level biology and subsequent reading tells me that gonads, external genitalia and secondary sex characteristics do not determine your sex. A man who has his penis cut off in a combine harvester accident is still a man. A woman born with no ovaries is still a woman.
We can identify the sex of a foetus when it is only a few cells. Before it grows gonads.
We also know that even when sexual development goes awry, we STILL only end up with a binary, either a male OR a female. Many DSDs are sex specific.
These, supposedly intelligent, people are trying to conflate sex and gender. They are very different things. Sex is based on fact, and is immutable and gender is based on feelings and can be fluid.
I really thought that the UK Supreme Court decision and Trump’s order would see the end of all this nonsense. But it seems like the narcissists won’t give up without a fight.
I see these organisations don’t provide any papers that prove this fictional ‘sientific consensus’. If sex is on a spectrum, then they should easily be able to produce someone who is 90% male and 10% female and vice versa.
In the current War of Narcissists, Trump and his team appear to in the ascendent.
I’m no expert here, but I don’t think that “sex characteristics are on a spectrum.” Depending on which sex characteristic one is observing, they are more or less sharply defined camel’s humps on the graph, not a spectrum. Some/Many are so sharply defined as to be quite nearly binary (or bimodal), others are somewhat more gradual and may have some overlap.
Although the UK now officially says there’s two sexes, trans nonsense continues:
https://www.dailymail.co.uk/news/article-14651559/amp/British-Olympic-swimming-heroine-Sharron-Davies-blasts-London-Marathon-organisers-anti-women-allowing-trans-females-compete-Sundays-main-race.html
Several groups have said they will be ignoring the UK ruling. Lloyds Bank and a few other employers, have said that they will continue to let men use whichever bathroom they want. They really can’t read the room and see how people feel.
At least now that we have the judgment it should be easier to take them to court for sex discrimination.
The NHS is in the middle of two tribunals over disciplinary actions against female nurses who have complained about men using their changing rooms. They say they are reviewing the ruling, and I hope the action against the nurses is withdrawn. It’s a disgrace that the cases were even brought.
These people don’t care about women’s rights at all. It’s like we have to start over.
Like many women of my age, I fought for my rights in the 70s. I had no idea I would i have to start the same fight all over again in retirement. 😡😪
My aunt was one of the Dagenham Ford machinists who went on strike for equal pay in the 1960s. She and her colleagues will be rolling in their graves.
The cabal of junior doctors in the British Medical Association (the group that wanted the Cass Review rejected) are also now fighting the Supreme Court decision and will make trouble if they can.
They are wasting their time. A decision by the UK Supreme Court cannot be reversed. It is the highest court, and their decisions cannot be overturned by any other court.
It is possible, however, for an act of parliament to legislate that men can become women, thereby overturning the court decision, but I don’t think any parliament would dare do that, especially as the Supreme Court decision was unanimous.
Oops. This was supposed to tag joolz’s previous comment.
“… disciplinary actions against female nurses who have complained about men using their changing rooms.”
Reading that makes me crazy mad. What a world.
The two cases.
The guy in the first one sounds like a creep. He asks the women when they are going to change. He has a girlfriend, so he obviously has a sexual interest in women, that must make the women even more uncomfortable.
https://news.sky.com/story/nurses-suing-their-employer-for-allowing-trans-women-to-use-their-changing-rooms-13160104
https://www.nursingtimes.net/policies-and-guidance/watchdog-sends-warning-to-nhs-fife-over-changing-room-dispute-04-04-2025/
Re the UK — and sex matters in general — every day I check via Google for JK Rowling’s latest post on X. I’m allowed that, at least. Never joined Twitter or BlueSky & can’t see going to X now because Elon, but if I were to do any of those, it would be to join X to see JKR’s full set of tweets. She’s devastatingly sharp.
I’m reminded, when I see her commentary & response to gender cranks, of the old joke:
He: It was a battle of wits!
She: How brave of you to go unarmed.
She’s amazing. Despite all the death threats, including a written threat of a pipe bomb, she has remained incredibly steadfast. She has a great sense of humour and I think it frustrates trans extremists that they can’t rattle her. She rises above their abuse.
Some sent her a photograph of themselves burning her books and videos, and toasting marshmallows over the flames. She replied that was ok because she already had their money, and warned them that burning the plastic containers may give off toxic smoke so she didn’t recommend eating the marshmallows. 😂
India Willoughby hates her as he can’t get her to stoop to his level. Exchanges between them are hilarious.
The mirroring site Nitter allows you to see posts and threads from X/Twitter without having to sign up to Elon’s site: https://en.m.wikipedia.org/wiki/Nitter
Amazing how these same people can take a complicated mammal like a whale from the fossil records and absolutely identify it as a whale on nothing more than an ear bone that definitively makes it an ancestral whale and therefore can be nothing else I tell you but a whale, because that ear bone. The word woman on the other hand…