@Perchik regarding self destruction of our species, once were are dead, done by our own way of life, darwin definately had his say. Environental suicide IS natural selection.
If we act in a way that will likely kill us off, and we are killed off – then nature says “be gone with you” – eventually sentient life may arise to wonder what all the ruins are from, where the owners went, and what killed the owners off.
I love this topic, so’ll meander a little here while pondering my avatar.
Do you ever stop and wonder if dinosaurs had achieved sentience before the time of the comet? – 65 million years, not even a pyramid would last that long IMHO.
There is a parallel in viral evolution. Viruses that kill the host too quickly don’t get spread and die off. Viruses that use you and leave you feeling molested but alive, live to find another living host. Natural selection by destruction of environment, host, food source is a constant and common selective pressure.
I really don’t think there is much we can do.