This is a sad story: sad for biology, sad for science communication, and perhaps saddest for Laura Helmuth, editor-in-chief of Scientific American. Over the past few years, Helmuth has injected a hefty dose of authoritarian progressive ideology into her magazine (see here for some of my posts on the issue). It’s gotten worse and worse, even though the readers, and her followers on Twitter, have repeatedly urged her to back off the ideology and restore the magazine to its former glory as the nation’s premier venue for popular science. But Helmuth is woke, and, being religious in that sense, simply can’t keep the ideology out of the science, just as an evangelist can’t help asking you if you’ve heard the good news about Jesus.
The tweet Helmuth put up this week (shown below) is a prime example, and it’s pretty dire because it distorts biology—in particular the work of scientists who spent years studying the genetics and mating behavior of white-throated sparrows (Zonotrichia albicollis). This is an interesting bird because both males and females show two forms (this is a “polymorphism”), with one form having a tan crown stripe and the other a white crown stripe. Here is a picture of the two forms from a PNAS paper.
The forms also differ in their parental behavior and courtship. I think you can get the differences by looking at the abstract of a paper by Elaina Tuttle, given below. Tuttle was an accomplished ornithological behaviorist who did part of her postdoc in Steve Pruett-Jones’s lab upstairs from me. It was her work that called attention to the involvement of inversions in the mating system of white-throated sparrows. Sadly, Tuttle died at only 52 of breast cancer.
Here’s a 2003 paper by Elaina on the species (found in North America) and its mating system (click to go to screenshot, and you can find the pdf here).
Her summary is below, showing that the two forms (“morphs’) mate disassortatively—that is, tan males prefer to mate with white females and vice versa. There is also a difference in their behavior, with white males and females being more aggressive during the mating and breeding season:
Organisms exhibiting genetic polymorphism often also exhibit true alternative life-history strategies in which behavioral tactics are genetically fixed. Such systems are ideal for the study of the evolution of life histories because the consequences of selective episodes can be more easily identified. Here I report an interesting and classic example of a species exhibiting true alternative strategies. Due to a chromosomal inversion, male and female white-throated sparrows (Zonotrichia albicollis) occur as two distinct morphs, tan or white. Tan and white morphs mate disassortatively, and this mating pattern maintains the polymorphism in relatively equal proportions within the population. In comparison with tan males, white males are more aggressive, frequently intrude into neighboring territories, spend less time guarding their mates, occasionally attempt polygyny, and provide less parental care. White females are also more aggressive and solicit copulation from their mates twice as often as tan females.
Note that they mention just two sexes: males and females, each characterized by their color. Just two sexes! The genetics of this system is complicated because, the genes causing the different colors and behaviors almost surely reside within a chromosomal inversion (a part of the chromosome that gets broken, turned around, and then reattached). This makes it hard to do genetic analysis. Tuttle explains this:
. . . . . almost all white birds are heterozygous for the inversion (i.e., 2m/2, where 2m represents the inverted chromosome and 2 represents the noninverted form), whereas tan birds are homozygous noncarriers (i.e., 2/2). . .
The disassortative mating and different behavioral strategies have combined to make this variation remain fairly stable in the population, though I’m not sure there’s a population-genetic model showing how this actually. works. (That would be hard, as it would require knowing a number of parameters that are difficult to estimate but are required for a good model.)
Further, the tan and white morphs occasionally mate with their own color (about 4% of the time, probably an underestimate because of sneaky mating). This kind of mating is called assortative—like mates with like. Because of this, the two forms are not reproductively isolated. That’s why they’re not called different species.
Note that there are just two sexes here, as virtually all scientific papers describing this phenomenon realize: males make sperm; females make eggs. Here are two quotes from the Tuttle paper:
This species is polymorphic, and both sexes can be separated into tan and white morphs based on the color of the median crown stripe (Lowther, 1961).
White-throated sparrows may be an exception to this rule because, regardless of fitness effects, the genetic alternatives are present in both sexes, there is likely to be evolutionary mechanisms maintaining multiple strategies. . .
Just two sexes, and every ornithologist knows this. Even if each morph mated only with its own kind, so that there was total reproductive isolation between the forms and they would, in effect, be two species, there would still be just two species, with each having two sexes.
Now the popular press has mistaken this system for the phenomenon of “four sexes”, which is just flat wrong. The biological definition of sex involves what kind of gamete you make, and here there are only two. Females make and lay eggs, males make sperm. For descriptions of this system showing “four sexes”, see here (Nature!), here, and here, among others.
That’s a distortion of the truth, and a misleading one that gender activists co-opt to say that “yes, animal sex is not binary”. They are wrong. But in fact Laura Helmuth did just that in her tweet, citing a paper from Ken Kaufman’s Notebook in the Audubon News. Kaufman says this (see more later):
It’s almost as if the White-throated Sparrow has four sexes. That may sound like a joke, but it’s actually a good description of what’s going on.
. . . Many different genes here are tightly linked to form a “supergene,” so that birds of one color morph also inherit a whole range of behaviors. The resulting effect is that the White-throat really does operate as a bird with four sexes. For anyone curious about the scientific background, you can read all the technical details here.
The Current Biology paper that the last link goes to does indeed say that the bird “operates as if it has four sexes”. And I found a 2020 paper by Maney et al. in Hormones and Behavior called “Inside the supergene of the bird with four sexes.” But while the paper uses “four sexes” in the title, it also notes that that is merely a “nickname” for the species. Maney et al. then correctly refer to “both sexes” throughout.
But if there are four sexes, what are those sexes? All you could say is “tan male”, :”white male”, “tan female,” and “white female.” But those are not sexes, as they don’t produce four different kinds of gametes. Nor is reproductive isolation between the tan and white morphs complete, so it’s not as if a “white male cannot mate with a white female”, which would be the case if these were four sexes. As I said, assortative (like-type) matings occur at least 4% of the time. Further, the offspring of some of those matings must, by virtue of the chromosomally-based system of mating, be fertile (i.e., if tan birds mate assortatively with tan birds, their offspring will be equivalent to the normal “tan” morph in behavior, appearance, and mating propensity).
If you’re a sane biologist and use the biological definition of sex, we have a species with two sexes, with each sex having two morphs. And the morphs mate disassortatively, but not completely so. It’s surely an interesting system, but deeply misleading to use it as an exception to the sex binary. It makes me angry when people like Helmuth do this, for on some level they must know they’re wrong.
Nevertheless, Helmuth wants to go with the popular press and with woke ideology rather than with science, and declares in the tweet below that the species has “four chromosomally distinct sexes.” (Even that isn’t true, as each morph has the same inversion type.) She underlines her ideology by adding her P.P.S.: “Sex is not binary,” as if this example disproves it. My P.P.S. is “Yes, sex is binary and you know it.”
Two points here: Helmuth is dead wrong, as biologists working on this system realize. There are not four sexes.
Second, she is being deliberately obtuse because she wants to buttress her view, expressed elsewhere, that “sex is a spectrum.” This, of course, is a trope meant to go along with the view that gender is a spectrum, which gender activists somehow want to read into nature itself, seeing the same spectrum in nature that they see in society. But as Richard Feynman said, “Mother Nature can’t be fooled,” and all animals and vascular plants obstinately show just two sexes.
What is amusing about Helmuth’s tweet is that she was SO wrong that the deluge of critical comments eventually prompted Twitter’s “community notes” program to correct what she said (remember, this is the Editor-in-Chief of Scientific American), and append an “added context” note saying she’s wrong—with the “context” noting that there just two sexes, and each sex comes in two colors.
I don’t know about other scientists or science editors, but if I was publicly spanked on Twitter like Helmuth was below, I’d be hideously embarrassed, and either correct myself (she won’t), or delete the tweet, which conveys scientific misinformation. (Update: She’s cut off the comments on her post, clearly perturbed that there were so many, with the vast majority being critical._
This is what started the Twitter fracas. Note the “added context”, which readers can upvote.
— Laura Helmuth (@laurahelmuth) May 17, 2023
And here’s what they call the “ratio” of comments to “likes” on her Tweet. This reflects the fact that the vast majority of people commenting on her tweet were critical. She has been, as the kids say, “ratioed”:
Scientists and informed laypeople immediately began going after this tweet, some polite and correcting it, others calling for Helmuth’s firing (I can understand that sentiment but I would never argue that anyone should be fired). One of the scientists, who had already debunked the sparrows as a violation of the sex binary, was Colin Wright, who wrote this on his website:
The second case study claims to investigate “the evolutionary consequences of more than two sexes.” Perhaps here we will finally be told what these new sexes are! But the first sentence moves the goalpost from “sexes” to “operative sexes,” which they never define.
The example they give of a species “with more than two sexes” is the white-throated sparrow (Zonotrichia albicollis). This species has two color morphs, males and females with either white or tan stripes. The more aggressive white stripe morph has a large inversion on chromosome 2, and the species mates disassortatively by color morph, meaning that white stripe morphs tend to mate with tan striped morphs. This chromosome inversion coupled with the disassortative mating by morph has led to a situation where chromosome 2 “behaves like” another sex chromosome.
He adds to that that in a tweet below issued as a comment on Helmuth’s tweet:
From the article:
"It's almost as if the White-throated Sparrow has four sexes."
"Almost as if" means that it's not even "as if," meaning that they in fact do not have four sexes, but rather just two. pic.twitter.com/lG9qEoAR1M
— Colin Wright (@SwipeWright) May 17, 2023
What happened? Helmuth blocked Wright (that’s what it means in the red rectangle below):
Wright then clarifies the story and calls attention to his being blocked. He’s right: Helmuth couldn’t abide the truth:
— Colin Wright (@SwipeWright) May 17, 2023
Emma Hilton also replied to Helmuth:
And Emma got blocked, too:
However, Carole Hooven, another critic of the “non-binary” view of sex, doesn’t seem to have been blocked. Perhaps I’ll be too, but I haven’t been yet.
What’s sad about this is that the reproductive biology here really is unusual and fascinating, but the emphasis is misplaced on support of a particular ideology.
— Carole Hooven (@hoovlet) May 18, 2023
Finally, Agustín Fuentes, the cultural anthropologist from Princeton whom we’ve met before, retweeted Helmuth’s post, for he’s denied the sex binary too, and in Scientific American!). But being thin-skinned, he puts in an addendum saying that the quote he gives is not his own. But he still apparently embraces the idea that there is no sex binary in humans.
to head off all the snarky comments…this is NOT MY QUOTE..it is directly for the author of the essay and in the actual paper referred to. Click the links, do the reading.
— Agustin Fuentes (@Anthrofuentes) May 17, 2023
To sum up, Helmuth is tweeting wrong things about biology in the service of her ideology, an ideology that she doesn’t just embrace, but has infused into the magazine she runs. Perhaps Scientific American wants to become Ideological American, but I’m hoping things will turn around. They would if Helmuth could simply adopt the idea that she shouldn’t use the magazine as a mouthpiece for her politics, but she won’t do that. Also, she refuses to engage with scientific criticism, not a good look for an editor. This exchange exemplifies that:
@laurahelmuth why do you block people for pointing out inaccuracies with your claims?
Surely the more intelligent & mature thing to do would be to acknowledge, understand & retract or correct your statement?
— 1122100202100 (@TheyGoneYet) May 18, 2023
And if I were friends with Helmuth, I’d tell her this.
h/t: Steve, Colin