Now I'm not going to claim this as the truth because I honestly have no clue but my theory is that it's easier on four legged জন্তু জানোয়ার that way just because of the way their bodies are structured. So maybe জন্তু জানোয়ার like gorillas and monkeys can have females topping to.
I've never seen female জন্তু জানোয়ার topping. I think primarily because missionary and doggystyle makes it easier for the sperm to find the egg generally. People have ব্যক্ত that in referenced to human sex so ya as far I am aware of we are the only জন্তু জানোয়ার that it is optional for the female to top.