Talk politics.

Eh, I think humans aren't alone in this, necessarily, we're just the species that does it most thoroughly. Elephants literally deforest entire regions, and there are areas where life went extinct from overstretching the ecosystem without human action. I think it's not even the omnipresent nature of human influence so much as that unlike say, ants, humans are large primates which leads to an influence that belies anything one would necessarily expect. I wonder how much influence archaic hominins like Neanderthal man had on the environment, come to think of it?