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Emma Hilton Profile picture
Emma Hilton
@FondOfBeetles
Developmental biologist. All views are my own. Manchester. Peri-clownfish. Sex Matters.
dniklasd Profile picture Steve Ellwood 🏴󠁧󠁢󠁳󠁣󠁴󠁿🟥 🕸️ Profile picture kiddphunk Profile picture A. S. Profile picture Jeni040866 Profile picture 52 subscribed
Apr 8 • 21 tweets • 8 min read
Let’s examine this list of “tranimals”.

Trigger warning: includes clownfish.
Image Clownfish. Some dominant males can change their biological sex to female. We know they have switched sex because they change their gonad tissue, stop making sperm and start making eggs.

Two sexes? Yes.
Sex change? Yes.
Trans Nemo? He’s way down the pecking order of “dominant male”. Doubtful clownfish have gender identities.Image
Mar 21 • 6 tweets • 1 min read
Here, we argue:

1. We disagree with the assertion that the IOC framework [fairness, inclusion, and nondiscrimination on the basis of gender identity and sex variations] is consistent with existing scientific/medical evidence and question its recommendations for implementation. 2. Testosterone exposure in male development:
--> physical differences between male and female bodies
--> male athletic advantage in muscle mass, strength and power, and endurance and aerobic capacity.

The IOC's “no presumption of advantage” principle disregards this reality.
Feb 21 • 14 tweets • 3 min read
You know that story about breast milk from a man being as good - BETTER - than that from a woman?

telegraph.co.uk/news/2024/02/1… You know it, the one informing policy in at least one NHS trust?

thetimes.co.uk/article/transg…
Jul 31, 2023 • 5 tweets • 1 min read
Yo @neiltyson

What does “feeling 80% female” actually feel like?

Is it only 80% of your clitoris being sliced off in childhood? Maybe 80% probability of being kidnapped to warlords? You bleed through your knickers 4/5 periods? Only 80% of men try to control your fertility? Female people - women - are real human beings, my friend.

We aren’t a feeling, whether 100%, 80% or 0.01% of the time.

We are not 80% of a skirt, or 80% nurturing, or 80% good at fucking handwriting.
Jul 11, 2023 • 9 tweets • 2 min read
Semenya does not have unusually high amounts of testosterone. Semenya has amounts of testosterone entirely congruent with being male. ⁦⁦

@SkyNews⁩ ⁦@SkySportsNews⁩
news.sky.com/story/olympic-… Here @SkyNews repeat one of the most pervasive lies in sport, and one that has held back honest (and admittedly often uncomfortable) discussion about male bodies with male advantage in female sport.
Jun 13, 2023 • 23 tweets • 4 min read
The argument that because males suppressing testosterone often have very low testosterone levels (duh, the drugs typically work), it must therefore be fair or just for those males to compete in female sports is painfully misguided.

Here’s why. Let’s take a thought experiment, starting with the current male 100m Olympic champion, Lamont Marcell Jacobs. He won gold in Tokyo in 9.8s. He’s not Usain Bolt speed, but Bolt is retired and probably eating chicken poppers on a beach right now. Image
Jun 5, 2023 • 9 tweets • 2 min read
Women have, for time immemorial, sought abortions. If abortions are safe and legal, women seek safe and legal abortions. If abortions are not safe and legal, women seek unsafe and illegal abortions. For thousands of years, women have sought abortions. They have done so with an arsenal of ingested or inserted toxins, with the forceful wielding of sharp tools, with the blunt trauma of heavy tools, with dodgy internet pills.
May 4, 2023 • 10 tweets • 3 min read
Revisiting a previous thread of mine on sexual dimorphism.

Sexual dimorphism: Systematic differences between the two sexes of a gonochoristic species of a physical characteristic (or set thereof), not including reproductive anatomy. Some sexually dimorphic characteristics are non-overlapping (e.g. green duck heads) while some are very overlapping (e.g. human height). The extent of overlapping observation/measurement is irrelevant. The only requirement is a robustly-detectable difference between sexes. Image
May 2, 2023 • 24 tweets • 4 min read
Like others, I have been eagerly awaiting the publication of Professor Fuentes’ much promised piece on sex and binaries.

However, @hoovlet appears to have linked to an article that is no more than five year old, Facebook-level attempts at gotchas.

I’m a bit confused. Fuentes: “There are those, politicians, pundits and even a few scientists, who maintain that whether our bodies make ova or sperm are all we need to know about sex.”

Correction: whether our bodies make ova or sperm are all we need to know to identify which sex we are.
Apr 1, 2023 • 7 tweets • 2 min read
Denying that there are two sexes is the equivalent of flat earthing. It’s so laughably nonsense that we need to look deeper into the why. Why are apparently sensible people (not Monty) saying that sex is: not noticeable, not relevant, not real?
Mar 23, 2023 • 4 tweets • 1 min read
I am getting a lot of love right now (and that’s lovely). There is no single person who Hadoukened this. It took a lot of work from many people, and it’s great news.

But let me tell you about Cathy, @cathydevine56, whose work with female athletes has become so important. Cathy has tirelessly sought and surveyed female athletes, diligently collated data and published them in rocking journals.
Jan 27, 2023 • 10 tweets • 2 min read
The line:

Males who have, via male development, got longer bones, bigger muscles, a larger lung surface and sharper hand-eye coordination *than would have been acquired in the absence of male development* should not be in female sports. The location of male advantage is at the level of the individual.

A female clone of Michael Phelps would have all the “swim genes” in the absence of male development.

So she’d be shorter (still tall), weaker (still strong), smaller shoulders (still big).
Jan 15, 2023 • 8 tweets • 2 min read
On a more broad point here.

The existence of uncertainty in scientific study is, for some, the gap into which they wedge their ideology. In the example below, the premise is that if you cannot be certain all of the time, you cannot approach certainty any of the time. Scientists have various amount of uncertainty associated with their data, typically linked to the complexity of their system and the cumulative effect of possible variation in multiple components.

Developmental biologists deal with greater uncertainty than particle physicists.
Jan 3, 2023 • 8 tweets • 1 min read
On “binary”.

Binary. Two in number.

Like the number of sexes. Like many words, “binary” (“two in number”) can be linked with other words to make new concepts.

A binary star is star system composed of two stars. A binary compound is a substance composed of two elements. Binary fission is the splitting of one mother cell into two daughters.
Dec 31, 2022 • 4 tweets • 1 min read
It’s awful when any female loses places or records to a male. But this is particularly personal.

I’m a 46-year old woman with a couple of marathons (run in my early 40s) under my belt. We know that female athletes lose performance between the ages of 45-55. We know that this is the effect of peri/menopause.

I know how hard it can be to try and manage tiredness, erratic biology, anxiety, soreness. To have to battle with the weights to protect your bones.
Dec 30, 2022 • 7 tweets • 2 min read
There are plenty of sensible objections to C’s suggestion - males and females of the same weight and height do not have the same strength etc.

Let me tell about a tiny thing…. Put men and women in front of a screen and a trackpad, and tell them to watch the wiggly line on the screen while tracing the shape with their hand…
Dec 29, 2022 • 12 tweets • 5 min read
The US hasn’t woken up yet…come on, TERF island… Here is my shameless pitch.

This year, Hilton and Lundberg (transwomen in sports) entered the Top 1000 for public engagement with academic papers (of >22 million records).

link.springer.com/article/10.100…
Dec 24, 2022 • 4 tweets • 1 min read
OK. What can I practically do to prep for cooking dinner tomorrow? Is it only peeling sprouts? Right.
1. Potatoes, carrots and parsnips are parboiled and in water in fridge. Coating for potatoes and parsnips rubbed.
2. Sprouts are ready to go. Pancetta and chestnuts chopped.
3. Cabbage and red onion sliced. Apple I think I’ll leave until tomorrow :)
Dec 17, 2022 • 7 tweets • 2 min read
I’ve just watched Colin @SwipeWright and Alice @AliceDreger on @heterodorx

I need to process. First, if that was typical of @heterodorx I’m unimpressed.

Second, Alice fails repeatedly to understand the opposition argument. She doesn’t have to agree that it is an appropriate framework blah blah. But literally no understanding.
Dec 16, 2022 • 13 tweets • 21 min read
@zekouse @ForrestValkai @Phildidgee @DrFletchington @Redsabr @CallMeSibby @GodlessKafir If you think that, you haven’t read anything I’ve written.

Sex is an evolved function. There are two, organised in various patterns and in varying body types across almost all complex life. @zekouse @ForrestValkai @Phildidgee @DrFletchington @Redsabr @CallMeSibby @GodlessKafir Humans are gonochorists. We have a class of individuals who contribute sperm to the next generation, and a class of individuals who contribute eggs to the next generation.

Like almost all animals.

A system described as “almost inevitable” in evo bio.
Dec 15, 2022 • 14 tweets • 5 min read
This is nice. New research for @SexMattersOrg by @matildagosling strongly suggests that puberty blockers and hormone treatment are no better for teenagers’ mental health than taking a placebo.

sex-matters.org/posts/publicat… @SexMattersOrg @matildagosling Some thoughts/explanations.

Those running experiments on gender dysphoric children have long-argued that running a placebo control (children who don’t receive the experimental intervention, in this case, blockers and hormones) would be unethical.