To dismiss the current extinction wave on the grounds that extinctions are normal events is like ignoring a genocidal massacre on the grounds that every human is bound to die at some time anyway.

Today Charles Darwin is best known for establishing the fact of evolution and for recognizing the major role of natural selection in driving it.

I decided that now is the time to start doing the things that really interest me and I find important. It was in the 10 years of the MacArthur grant that I began working on my first book... and I began putting more work into environmental history.

The southward advance of native African farmers with Central African crops halted in Natal, beyond which Central African crops couldn't grow - with enormous consequences for the recent history of South Africa.

The metaphor is so obvious. Easter Island isolated in the Pacific Ocean — once the island got into trouble, there was no way they could get free. There was no other people from whom they could get help. In the same way that we on Planet Earth, if we ruin our own [world], we won't be able to get help.

The United States has long thought of itself as the land of infinite plenty, and historically we did have abundant resources. But now we are gradually exhausting our fisheries, our topsoil, our water. On top of that, we're coming to the end of world resources.

[T]he values to which people cling most stubbornly under inappropriate conditions are those values that were previously the source of their greatest triumphs.