[CamperBob2]

gender being a social construct, mice don't have it.

You have to be careful there. Plenty of individual animals in the wild exhibit social behaviors that we would associate with unconventional gender roles if they were humans. There are known evolution-based rationales for many if not most of these behaviors, and it's safe to say there are unknown evolution-based rationales for the rest.

We're not special.

[krapp]

Homosexuality is not transgenderism. A homosexual man can still identify as a man and be attracted to men. Being attracted to a man doesn't make them equivalent to a transwoman.

Also conventional gender roles change over time, and vary by culture, because gender is performance. It used to be conventional for men to wear high heels and makeup and kiss each other on the mouth, and sexual relationships between men weren't always considered transgressive of masculine norms.

[CamperBob2]

Yep, all very true.

I spent most of my childhood believing that homosexuality was unnatural, inherently sinful, and entirely unique to humans, because that's the spiel that the local Southern Baptist preachers were selling. The same is true for things we call "gender roles." Some male animals act in ways we once reflexively associated with females of their species, and vice versa.

I'll edit the comment to remove the reference to homosexuality, though, because that point wasn't especially clear or useful.