@Coffeeandaworry
My female cat 'phantom sprays', where she appears to be spraying like a male cat but with no urine. I've never seen it before but it's known to happen.
We had a queen and four (neutered) toms. The queen used to 'phantom spray' too - our vet said it was a sign of dominance/marking her turf, because even though no spray came out... her scent was still there. In fairness, she was "top cat" as the toms (and our dog) were all slightly terrified of her!
Also, chickens change genders - again rare, I think 1 in 100,000 if I'm remembering the statistics correctly - but it happens. We had a hen, whom we'd seen lay eggs (put my son off eggs for life...), become a rooster. Grew more wattle, started to crow, even had little stubby talons at the back of the feet start to form. We already had a rooster, but he preferred to spend his time perched on me, so one of our hens instinctively seems to have decided they needed to step up and protect our little flock. Again, to do with dominance. Of course our little hen-to-rooster couldn't fertilise any of the eggs - although they did mount one of our hens, so they gave it a fair go! - and according to our vet, would have had an injury to one of the ovums, or perhaps even a tumour, causing them to produce more testosterone than normal, thus changing them from female to male. Knowing how much of a Mama's Boy our actual rooster was, though, I'm more inclined to go with our family's theory than our "miracle hen" simply went "oh, fucking hell... someone's got to sort things out!" and physically altered their biological sex.
So it's not entirely beyond the realms of possibility, but... as mad as our world has become, I find the above anecdote implausible. Unless you were there, taking notes, for example, FindtheTruth (ironic name, if ever I've heard one on here!)?