Increasingly developing countries are asking for aid to help deal with the consequences of climate change, which we don't want to give.

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.

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

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."

As best as can be determined, the world is now warmer than it has been at any point in the last two millennia, and, if current trends continue, by the end of the century it will likely be hotter than at any point in the last two million years.

It seems that the Neanderthal DNA that modern Europeans and Asians (and also Native Americans and basically all non-African people) are carrying around is random. This means there are different bits and pieces in different populations, but it doesn't seem to amount to much that's significant.

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.