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.

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.

There's this idea of shifting baselines. It was coined by a guy named Jeremy Jackson. It's the idea that every generation takes what it sees, and says, "Okay, well, that's the norm."

[On the birther movement:] Here we are, quadrillions of bytes deep into the Information Age. And yet information, it seems, has never mattered less.

Most of us live in parts of the world where we don't expect to see much, and we wouldn't necessarily notice things that are crashing.

Somewhere in our DNA must lie the key mutation (or, more probably, mutations) that set us apart—the mutations that make us the sort of creature that could wipe out its nearest relative, then dig up its bones and reassemble its genome.

I don't think there are too many places left that humans haven't pretty thoroughly explored.