Over the last half a billion years, there have been five mass extinctions—times when the diversity of life on earth suddenly and dramatically contracted. Scientists around the world are currently monitoring the sixth extinction, predicted to be the most devastating extinction event since the asteroid impact that wiped out large dinosaurs. And this time, the cataclysm is us.

In this podcast, join Elizabeth Kolbert, staff writer for the The New Yorker magazine and author of the new book The Sixth Extinction: An Unnatural History, and Michael Novacek, senior vice president and provost of science at the American Museum of Natural History, as they discuss the process of extinction—and the role humanity plays in it. The event was moderated by science writer and video journalist Flora Lichtman. This event took place at the Museum on February 27, 2014.