God said "Let there be black rights across all the corners of the world!" And then He made the Earth round.
What do you imply with your joke? That blacks shouldn't have rights?
It's a joke about the dumb shape of the earth. You see, people without an education or who didn't pay attention in school don't get it.
I get that what you are saying about black people not having any rights is just a joke, but it is a very distasteful one and I seriously recommend you stop uttering that to other people. What you can do instead is to try and be educated with black rights and how it is important that we still have a lot of work to do to help them succeed.