Which ones have to go, and how do we make that happen?

Given the fact that reality cannot be fooled or evaded, it will at some future point take these decisions out of our hands and simply make it happen whether we like it or not.

We may happen to be better equipped than any other species to exploit natural resources for our own exclusive use, but we live on a finite planet with finite resources which is being rapidly thrown into disequilibrium by our ability to monopolize the best habitat and to mine aquifers, forests, metals, oil, gas & coal. There used to be a term, "a fool's paradise" and that is where we are living today.