This image quote shows how humans are seen as merely a virus/parasite to the Earth. As a human species, we have spread ourselves throughout the world via cities, destroying nature and using up resources. We are like a case of the fleas to the Earth, and the Earth will eventually shake us off and move on.
I originally got this idea from the Joe Rogan podcast; he talks about these kinds of things often. Also, George Carlin spoke about how we are insignificant to the Earth (and will eventually be ridden of) in one of his stand-up performances.