Lessons from clownfish school: animals can switch sexes, only humans can be transgender
From frogs to cardinals, sex in the natural world is malleable. But ‘transgender’ is a uniquely human label for a uniquely human experience of autonomy and personal choice
Mel Woods is the senior editor, audience engagement at Xtra Magazine
Feb. 24, 2025 8 min. read
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Despite what some politicians in Canada and the U.S. say, the "biological facts" of sex and gender don't fit into an uncomplicated binary.
Illustration: Beatrice Hayward / The Narwhal
Picture this: you’re a male clownfish moving on up within clownfish society. The local anemone is bustling, and for society to function, each fish, including you, fills a specific role in the pecking order. Over time, you swim your way up the ranks and eventually make it to be second in command — vice-clownfish, if you will.
One day, the alpha clownfish dies, leaving a gaping leadership void.
In this fish version of Succession, there aren’t terrible adult children all vying to become top dog. There’s no actually-not-the-eldest boy Kendall Roy primed to step in, Roman Roy having a meltdown, or Tom Wambsgams scheming to ultimately take it all. No, it’s meant to be you and only you! But to do that, one big thing about you has to change — because in clownfish society, a female is always in charge.
So you, the clownfish heir-apparent, do the obvious thing: you become a female.
Seems simple enough right? Something triggers genetically, and your little clownfish body changes to suit your new role. Research has shown again and again and again that in the clownfish world, that’s how you get ahead. Those are, to borrow a phrase from U.S. President Donald Trump, the “biological facts.”
When it comes to transgender and non-binary human beings, some intolerant politicians seem endlessly fixated on trying to prove biology wrong and declare that a rigid gender binary is the only truth there is.
But they couldn’t be further from the truth.
Green frogs sometimes spontaneously transition from male to female. Photo: Universal Images Group / The Canadian Press
Evolutionary expressions of variability in sex are also present in humans. It’s one of the reasons a number of politicians — in Canada, too — have such a hard time actually defining “biological sex,” because there will always be exceptions.
Sure, people who transition aren’t triggered by some environmental cue in the exact same way that sex-changing clownfish is. But it’s still biological. It’s still evolutionary. And it’s still natural — just with the added sentience and agency that makes us human.
Name a gender, any gender!
In a recent interview for CP24, Conservative Party of Canada leader Pierre Poilievre claimed there are only two genders. It was a comment delivered with a smirk and a challenge, simultaneously an anti-transgender declaration and a trap, inviting opponents to resist his declared “reality” and wade into a fraught debate where human rights, science, culture and opinion churn together into zero-sum muck.
Poilievre likely felt empowered to say such a thing thanks to the freshly inaugurated Trump, who used the first hours of his presidency to sign an executive order declaring there are “only two genders.” His administration has since targeted everything from gender-affirming care for young people to trans youth in school sports to restricting — even reportedly confiscating — trans peoples’ passports in an all-out attack on transgender rights.
Then again, a wave of legislation limiting the rights of trans children and their parents in New Brunswick, Alberta and Saskatchewan in recent years shows Poilievre’s comments are not the first attack levied against trans youth by Canadian politicians.
Former New Brunswick Progressive Conservative premier Blaine Higgs called gender dysmorphia “trendy” — a particularly hurtful statement given how at-risk transgender youth are — while rolling back protections for trans and non-binary students (which current Premier Susan Holt has thankfully reversed). Alberta’s United Conservative Party Premier Danielle Smith’s slate of policies are the most restrictive anti-trans legislation in Canada yet, framing trans kids as confused and misguided and trans girls as a “threat” to women’s sport (neither of which is true).
In 2018, a lioness named Bridget at the Oklahoma City Zoo sprouted what the zoo called a “mini-mane” on Instagram.
But Trump has the biggest stage, and Poilievre has indicated he might lean into many of the American’s policies on this front. And his government’s statements continuously reiterate an idea of “biological reality” or “biological truth” to sex (which relates to physical characteristics you’re born with, usually) and gender (a socially-constructed category of actions, dress and manner, often assumed based on sex).
They suggest that gender — or sex, for that matter — is unchangeable, and the existence of trans and non-binary people is merely performance or resistance.
Nevermind the fact humans are constantly “resisting” biological reality. If this is your argument against hormone replacement therapy or gender-affirming surgery, you should also take issue with chemotherapy, laser eye surgery and Viagra, because those are equally “unnatural.”
Most earthbound slugs and snails have both sex characteristics, and they can self-reproduce if necessary. Photo: Uytae Lee / The Narwhal
Every day, surgeries are performed to force people’s vastly unique bodies to conform to traditional gender expressions. The obsession with gender-affirming surgery for young trans people is particularly misinformed. Just look at the numbers: a 2019 study by the Harvard University school of public health found that, for every one trans kid getting top surgery in the U.S., there were 32 cisgender boys getting surgical chest reductions. Those procedures, of course, aren’t deemed unnatural.
Such weaponization, unsurprisingly, disproportionately affects people marginalized in other ways, such as the spectacle of targeting non-white female athletes like Castor Semenya,Dutee Chand, Imane Kheif and Lin Yu-Ting for “gender testing” in competition.
The evolutionary advantage of switching sexes — or being more than one
From clownfish to cardinals, sex in the natural world is malleable — in fact, that malleability is a key part of evolutionary advantage. The real biological reality is constant change.
Hawkfish typically start off as females, before transitioning to males, thanks to environmental cues. And they can change back if the environment calls for it, such as if their social group loses too many females or if a larger male challenges them.
Butterflies have been observed with intersex traits — that is, multiple sex characteristics — including wing patterns typical of both male and female insects. Thanks to coloration, intersex traits are easy to spot in birds such as cardinals, which have been observed showing an even split down the middle of bright male colouring and brown female colouring.
Environmentalist drag queen Pattiegonia with makeup evoking a cardinal with both male and female sex characteristics, known as a bilateral gynandromorph.
Most earthbound slugs and snails are born hermaphrodites: they always have both sex characteristics, and can self-reproduce if necessary.
Female lions have been spotted growing manes and exhibiting “male-like” behaviour such as mounting other females (we love a butch top).
Frogs who spontaneously transition from male to female were thought to do so because of exposure to estrogen from human pollution — but new research shows that happens naturally in the wild too.
None of these discoveries are particularly new. Research on the malleability of sex in the natural world has been conducted for decades. It’s not trendy — and it’s not being done to try to justify trans humans’ existence.
Being trans is an expression of humanity and the power of personal choice
While science — and biological facts — overwhelmingly support a variety of creatures transitioning, I’m not here to tell you that animals can be transgender. As much as I love the idea of a transsexual creature of any kind, I actually don’t think being trans is something animals outside of humans can be.
Clownfish can change their sex when it is evolutionarily necessary. Birds and butterflies can be multiple sexes at once. Slugs can reproduce asexually. Female lions can grow manes.
But gender, and specifically the idea of two genders, is a uniquely human construction. A non-human animal can’t be transgender, just as it can’t be a man or a woman. These fish don’t know they’re changing from “boy” to “girl.” They’re just doing what they have to do to survive. For so many animals, the biological reality is that sex is meant to change.
Demonstrators advocating for the human rights of transgender people march in downtown Halifax in 2023. Photo: Darren Calabrese / The Canadian Press
But being transgender is a uniquely human label for a uniquely human experience — in a good way. What separates humans from animals is our sentience, our big brains full of thought and consideration and choice and identity. We can choose to change our reality for the better, and modern medicine exists to support that.
The clownfish doesn’t have any say in its sex change. Nor does the bird, or the frog. But people are able to examine our reality and choose something better for ourselves. Transitioning is the ultimate act of human biological and philosophical reality, the same as choosing to save a life by cutting out a malignant tumour, or choosing to put a cast on a broken bone to help it heal.
Non-binary writer Sabrina Imbler’s 2022 memoir, How Far The Light Reaches, is a luminescent book that looks at aspects of their life through the science of 10 sea creatures. In an interview following its release, Imbler frames transness in the natural world as a distinctly human projection.
“Our understanding of being transgender is very specific to our own experience as a species. I tried to understand the limits of the metaphor and not equate one thing to another, and I tried to celebrate all of these different ways of having a body and being with another body that exists in the ocean,” they said.
The only real biological reality is change, and that’s what trans people represent.
We’re the living embodiment of one of humanity’s deepest traits — personhood and autonomy. When a male clownfish becomes a female clownfish, it’s doing it to survive. When a person transitions, we’re also doing it to survive.
But unlike the clownfish, at least consciously, we’re also choosing to do it, and choosing to survive. The independence, intellect and autonomy to choose one’s own path is one of the most human things I can imagine. It’s what separates us from animals.
And that’s what politicians like Poilievre and Trump are most afraid of — the choice, possibility and hope for a better, more human life that being trans represents.
Another year of keeping a close watch
Here at The Narwhal, we don’t use profit, awards or pageviews to measure success. The thing that matters most is real-world impact — evidence that our reporting influenced citizens to hold power to account and pushed policymakers to do better.
And in 2024, our stories were raised in parliaments across the country and cited by citizens in their petitions and letters to politicians.
In Alberta, our reporting revealed Premier Danielle Smith made false statements about the controversial renewables pause. In Manitoba, we proved that officials failed to formally inspect a leaky pipeline for years. And our investigations on a leaked recording of TC Energy executives were called “the most important Canadian political story of the year.”
Here at The Narwhal, we don’t use profit, awards or pageviews to measure success. The thing that matters most is real-world impact — evidence that our reporting influenced citizens to hold power to account and pushed policymakers to do better.
And in 2024, our stories were raised in parliaments across the country and cited by citizens in their petitions and letters to politicians.
In Alberta, our reporting revealed Premier Danielle Smith made false statements about the controversial renewables pause. In Manitoba, we proved that officials failed to formally inspect a leaky pipeline for years. And our investigations on a leaked recording of TC Energy executives were called “the most important Canadian political story of the year.”
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