We've all descended from a common ancestor, but, as Homo sapiens, we no longer brachiate through trees and have long abandoned our stone tools for iPods. Evolution has shaped us into the big-brained, bipedal, text-messaging specimens we are today. But it didn't happened without a lot of pressure. We'll look at some of the forces that have driven human evolution - from the snake-phobia that sharpened our eyesight, to the anger-management that was a prerequisite for civilization.Also, how your Blackberry may be changing the brains of future generations. And, are we engineering our own successors through robotics?Guests: Lynne Isbell - anthropologist, University of California, Davis Timothy Taylor - archeologist, the University of Bradford in the U.K. Nicholas Wade - science writer, New York Times, author of Before the Dawn: Recovering the Lost History of Our Ancestors Lee Gutkind - author of Almost Human: Making Robots Think Less