Three ecology and evolution societies finally remove their “sex definition statement” from the web

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.org

Daniel Bolnick, PhD
President
American Society of Naturalists

Jessica 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.