I don't even care about the rest of the discussion honestly, but intersex/hermaphrodites prove that humanity does have more than 2 rigorously defined genders, let alone sexes.
I'm just saying, the whole, "there are only 2 genders" is scientifically incorrect. You have to deny that intersex (non-males and non-females) even exist to hold that viewpoint of there being only 2 genders. To admit that there is some third option (non-male/non-female) means that humanity isn't just limited to male/female options.
This post has nothing to do with transsexuals BTW, I'm talking about people who are born without being either male or female. These people make up about 0.05-0.1% of the population so it's not just like it's 1 or 2 outlier people worldwide. This is a real condition that humans are born with (where they are neither wholly male nor wholly female)
Intersex people don't fall into the standard male/female genders and hence humans have more than just the 2 genders (even without getting into transsexual discussions). Anyone who says otherwise simply isn't being scientific/factual.
Everyone interested in the actual science, complete with the names of genes and citations of peer reviewed studies should watch this: