These single-celled organisms are extremely sensitive to environmental changes.

Asteroids may be less dangerous than they've been made out to be.

We're quite confident we're on the right track.

Dinosaurs are very popular, and the asteroid theory is sexy, it's a perfect story, and in the past few years it's all you've read in the popular press.

I am here to give the American people some straight talk about higher education. Some have said we might have cut financial aid for college students. The truth is we have expanded access to college for our neediest students through the record growth of the Pell grant program.

But once in a while you might see me at In and Out Burger; they make the best fast food hamburgers around.