If in your lifetime you watch a species go extinct, or plummet almost to the point of extinction, that is a sign that something really serious is going on.

Several decades ago, a detachment of the American right cut itself loose from reason, and it has been drifting along happily ever since. If the birthers are more evidently kooky than the global-warming "skeptics" or the death-panellers or the supply-siders or the Swift Boat Veterans for Truth, they are, in their fundamental disregard for the facts, actually mainstream.

Though it might be nice to imagine there once was a time when man lived in harmony with nature, it’s not clear that he ever really did.

If you're a conservation biologist in many fields, you're seeing your study subject disappear. People are in the position where they're chronicling radical decline, and that is not a position that conservation biologists want to be in.

We're talking really huge global-scale change, and I did not feel that I had the prescription for that kind of action, so I'm going to leave it to the reader.

When you drive to the grocery store, your intention is not to change the world, it just happens to have that impact. So we've done a lot of things without even realizing it, and yes, just being unusual, as you say, does not put you above, in a sense, any of the other organisms with whom we share this planet.

Neanderthals were pretty smart, and if we actively killed them off, then probably we did so in the same way that humans kill each other.