Did you know, that we have changed the earth's freshwater system so much that we've actually redistributed the weight of the earth so that it spins on a different axis? 

Creating dams and reservoirs from rivers all around the world has, redirected the water destined for the oceans into the land for irrigation and other human use. 60 % of rivers globally have been changed like this, and the water channelled into the land so that the masses on the earth's surface have been rearranged, changing the torque of the whole planet. This is measured by the length of a day or something, and has been found to be significantly altered. 

I don't know about you, but to me, if a single species on earth can change the movement of a planet without even meaning to, it could be unknowingly capable of so much more destruction.