Do you really think so? I look at pictures of the globe in a flat format of the earth, and mentally "fit the puzzle" together of where this and that country USED to be. Look at it, everybody.
You can see, for example, how South America used to actually tuck in with Africa. Do you see how North America might actually have been side by side with South America? That happened long before man was screwing around.
I don't believe we should be polluting, but neither do I believe that we really have any sort of impact, I believe that is FAR beyond OUR capabilities.