On this edition of Conversations, James Nestor talks with host Dan Skinner about “Breath: The New Science of a Lost Art.” Nestor has written for “Outside,” “Scientific American,” “The New York Times,” and many other publications. His book “Deep: Freediving, Renegade Science, and What the Ocean Tells Us About Ourselves” was a finalist for the 2015 PEN/ESPN Award for Literary Sports Writing.