applying the word "gender" in humans to the same concept we use for animals
I'm not aware of the word "gender" being commonly applied to non-human animals for any concept, other than grammatical gender. You might be thinking of the concept usually referred to as "sex".
If you want to follow that distinction, then I agree that "gender" doesn't point to anything real aside from what is commonly pointed to by the word "sex". Heck when "gender" first became used in its non-grammatical meaning, it was a euphemism for "sex" since the latter had acquired a meaning (as [Edit: an act]) that made it not necessarily SFW.
This thread is for asking any questions that might seem obvious, tangential, silly or what-have-you. Don't be shy, everyone has holes in their knowledge, though the fewer and the smaller we can make them, the better.
Please be respectful of other people's admitting ignorance and don't mock them for it, as they're doing a noble thing.
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