I don't really get to term myself an environmentalist at all, because I'm absolutely in favor of a "stewardship" model of using the earth's resources- meaning,

I don't really get to term myself an environmentalist at all, because I'm absolutely in favor of a "stewardship" model of using the earth's resources- meaning, in this case, that if we see fit to set the equilibrium point to some other level, then we should do so guiltlessly- however, my major concern is that we haven't successfully managed to create long-term viable ecologies via planning yet. We don't understand the many complexities associated with organisms yet -we understand a LOT, but there is a LOT MORE to understand before we can replicate nature through artifice! Under that view, things like biodiversity are valuable because they contribute to systemic stability - we can exterminate a species if we need to, nobody has to give us any further 'right' to do so (as in a typical attidue, "What gives you the right to play God with Nature?!")- but it is wise to take a preservationist attitude until we have a proven track record of creating long-term, moderately stable ecological systems - until we can replicate our 'Starship Earth,' we'd do well to keep from destroying it! In other words, at least for me, the currently preferred equilibrium point is one that maintains a semblance of the historical ecology's relative balance, because that's the kind of point where I and my descendants get to not go extinct, and once we can reliably replicate and control such ecologies, it won't matter much anymore, we'll be in a position to choose what happens to which things - right now is the tender point where can destroy naturally developed situations, but cannot reliably replicate them.