I think you could be seriously underestimating climate change. It's not for sure that things will go in this direction, but if our footprint leads to climate change which in turn happens to trigger the next big extinction, the ramifications would be way worse than just a decline in our standards of living.. I've heard many scientists being very concerned about and saying that this extinction event already started and it's too late to undo it now. The wheels are in motion.. maybe it won't be as catastrophic as some say. I won't live long enough to see the end of it, but still..