I'm addressing the necessity of sexual reproduction for the propagation of species. The only reason you or I exist is via sexual reproduction. I'm not looking at indivudual choices, preferences, or even society; rather, the species and its survival.
I
am looking at sex as a merely reproductive biological task here, and I am not differentiating humans from monkeys or pigs here, either. If we're looking at things from a current or societal standpoint, then my posts are moot.