methinks on this that we primarily consume, and we generate waste from that consumption. it is our waste products that i see as causing dramatic change in a variety of ecosystems ... change at a rate that likely has and will continue to result in mass extinction.
on global warming and change and so on, i subscribe to the notion that the world is always changing, indeed, the orbit of the moon around the earth is a little bit further every month (the effects of this are near catastrophic in the long run, loss of tidal action etc) just as when the moon was much closer its tidal forces were massive giving rise to great rapid change) .... but I digress , the world is always changing, and on rare occasions change is rapid, when change is rapid we typically observe mass extinctions.
Mass extinctions, when they get larger than average, generally get rid of everything above a certain size, i.e. things like us generally fair poorly in such circumstances.
this time around I am inclined to think much of our creativity and durability, but I certainly can see a path towards a collapse in civilization, a collapse in human numbers, a collapse in more complicated technologies and the rise of a dark tribal period with shortened harder lives, less art and time for leisurely exploits sharply curtailed.
I just dont know if the neocons give a hoot, and so they deny. I see evidence for a sort of rapture lust which I find a rather sad way to find value.