While ants exist in just the right numbers for the rest of the living world, humans have become too numerous. If we were to vanish today, the land environment would return to the fertile balance that existed before the human population explosion. Only a dozen or so species, among which are the crab louse and a mite that lives in the oil glands of our foreheads, depend on us entirely. But if ants were to disappear, tens of thousands of other plants and animal species would perish also, simplifying and weakening land ecosystems almost everywhere.

It's obvious that the key problem facing humanity in the coming century is how to bring a better quality of life - for 8 billion or more people - without wrecking the environment entirely in the attempt.

I see no way out of the problems that organized religion and tribalism create other than humans just becoming more honest and fully aware of themselves.

In fact, nothing in science as a whole has been more firmly established by interwoven factual information, or more illuminating than the universal occurrence of biological evolution. Further, few natural processes have been more convincingly explained than evolution by the theory of natural selection, or as it has been popularly called, Darwinism.

There can be no purpose more enspiriting than to begin the age of restoration, reweaving the wondrous diversity of life that still surrounds us.

No species ... possesses a purpose beyond the imperatives created by genetic history ... The human mind is a device for survival and reproduction, and reason is just one of its various techniques.

The worst thing that will probably happen-in fact is already well underway-is not energy depletion, economic collapse, conventional war, or the expansion of totalitarian governments. As terrible as these catastrophes would be for us, they can be repaired in a few generations. The one process now going on that will take millions of years to correct is loss of genetic and species diversity by the destruction of natural habitats. This is the folly our descendants are least likely to forgive us.