Funny how some animals changed sex DUE to lack of numbers in one population, rite? :P
I'm sure that is just too much of a science mindfuck for you.
Let me assure you tho, If there were only gay people left on earth, Humanity would not die out, because some people have this scope and reason and would opt to re populate anyhow.
It's not about who you are fucking man, but who you love. Idk why that's so hard.