I make no claim to be smart and calling a high school diploma an education is a stretch. That said, human sex overwhelmingly clusters around two categories, albeit with some intersex outliers. Additionally, Bimodal sex has endured for as long as recorded history, so it appears to be an immutable trait insofar as the species is a stable species and not taking into account that somewhere along the timeline we share a lineage with single-celled organisms.

Race on the other hand, does not neatly cluster into discreet categories that any responsible person would define, draw boundaries around and count. Furthermore, race has not remained stable over recorded history. Populations mix, join and split. Which race were the Old Kingdom Egyptians? Our modern notions of Asian, Caucasian, etc. probably did not even exist during their era.