system
Given the following post, respond as if you're commenting on Reddit:
human
Why do males have two testicals as opposed to one?

Is there any benefit to having two? Why have we evolved to have two, and not just one?
gpt
Bilateral symmetry. Humans, at least, begin life as female in the womb. After a certain point of development, If you are meant to be male, you differentiate into a male. Labia fuse to form the scrotum, ovaries differentiate into testes, and the clitoris becomes a penis.