What if it's just plain old XX vs XY chromosomes?

So rats have a built in gene sequencer and detect the base pairs directly?

Your friend's eye color is defined by some genes. You don't need a gene sequencer to see what they are.

(S)he can be wearing contact lens, though.

And the researchers can be taking drugs changing their smell, possibly changing the mice behaviour.

Right, but wehat you detect is the eye colour, not the genes that cause it. Similarly with the rats they detect the pheromones in a male's smell, not the XY chromosomes. So suggesting they detect the XY chromosomes isn't helpful.

To see the color you mean?

No, the color of irides.

Probably not, but why is that so far fetched? They'd just need to be dissolving it with chemicals, backed up by a neural network to identify the sequence (rat's brain, anyone?). That's kind of how smell works in general to begin with.

As for why rats may develop the ability to sequence XX vs XY - if rats with the ability to do so were killed far less than those without, then rats would quickly evolve the ability to do so. This could happen if males were the ones killing rats and not females. Actually, skip the 'probably not' I began with - it's a perfectly likely explanation that may or may not be true based on further study.

Or there could be a signaling molecule specific to sex that directly interacts with some receptive system in the animal. Maybe it's nose? DNA sequencing would be an awfully slow signal given the technology available to the organism...

You appear to be conflating several identifiably distinct things (e.g. identity, sexual orientation, role in society) under the label of "gender" and then wondering why people seem to treat them differently even though you've applied the same label to all of them. The contradiction is an artifact of your measurement technique.

It's still a developing field of study, but AFAIK the current thinking based on the evidence is that gender roles are largely social constructs while gender identity is at least partly based in biology (that is, the brain has some innate conception of gender even if many of the implications of those genders are filled in by society). And sexual orientation is yet another separate thing.

>If you believe gender is a complete social construct

IIRC the nature-nurture studies show that nature is atleast 50% of the cognitive result on growing up. Atleast since the studies also binned a lot of stuff into "nurture" without much consideration as long as it's not nature. It might be more.

Thinking that gender is a purely social construct is just backwards to everything we've discovered in modern science. People can be gay because of their upbringing but most of the time that is just how they are. Same with transsexuality, it's mostly how people are not how they want to grow up, which should receive utmost respect. (though on the other hand, if CRISPR advances more we might have a "gay cure" and a "trans cure". Especially the ethical debate of a "trans cure" would be interesting)

> Some of this feminist/transhuman thinking, [...] are not rooted in reality

Luckily not all feminists. My sister has been one of those hardcore feminists but after having a situation in which she had to decide between getting a good grade and fighting for injustice against women, she changed her attitude that she should not fight against injustice like that if she can't uphold her principles in all situations.

Her reaction to this study now, relaxed, would probably have been different a year ago. I think a lot of people might react badly to the study and I'll keep an eye on it.

Reactions to studies are a study of humans in of itself already, observing the acceptance of data by a specific group can tell a lot about a group. Like pheromones can tell a rat a lot about a person.

Sorry what I really meant was that "I think we're probably still figuring out the actual cause of why the rats behave the way they do"

In general I don't think it's as simple as being one way or the other, some people certainly seem to innately feel they were born into the wrong gender, and just want that set right, while there seem to be other people for whom it seems to be fluid, that want to be able to choose and change. I don't see it's much of any of the rest of our business other than we should make them welcome in society just like anyone else.

As far as it being a 'social construct' I think the whole thing that "people with XX chromosomes must be women and people with XY must be men, or alternatively people born with penises ...." is obviously a social thing - likely tied to rigorous western sex roles and trying to force people into them - other cultures have provided places for people with differing genders - Fa'afafine, Hijra etc and traditionally treated them differently than in the west ... so yes definitely a 'social construct'

This last point was recently covered on wrongthink blog Status 451:

https://status451.com/2017/11/05/i-see-trad-people/

When people think of each other as blank slates and make progressivism the only acceptable viewpoint, maybe those inclined towards social conservatism just come out doing this "progressive in name only" thing, LARPing the themes of the last century in lieu of a consistent set of values.

There’s definitely a schism along the fault lines you describe. If you’re not familiar with the concept of a “TERF”, look it up.