Not wasting any water bottles is good. Not leaving the lights on is good. Turning the thermostat down in the winter, up in the summer, is good. But the best thing any of us in the developed world, especially in the United States, can be doing is talking about it.

Evolution is a theory, and it's a theory that you can test. We've tested evolution in many ways. You can't present good evidence that says evolution is not a fact.

I've always loved airplanes and flight. The space program was really important to me as a kid. I still have a photo of Armstrong and Aldrin on the moon in my living room.

The US Navy has several people on every ship that can navigate by the stars. They don't fool with that.

Evolution is one of the most powerful and important ideas ever developed in the history of science. Every question it raises leads to new answers, new discoveries, and new smarter questions. The science of evolution is as expansive as nature itself. It is also the most meaningful creation story that humans have ever found.

You stop planetary exploration, those people who do that extraordinary work are going to have to go do something else.

There really is no such thing as race.