Trees have long been imagined as the earth’s lungs inhaling carbon dioxide and exhaling the oxygen needed to support life. That life, too, is important for sustaining the earth. One scholar suggests that the animals that fill the planet’s landscapes serve as earth’s heart and arteries without them, the earth would be little more than a barren rock. The way that animals make our world is the focus of this episode of Stats and Stories, Joe Roman is a conservation biologist, marine ecologist, and editor ’n’ chief of Eat The Invaders. Winner of the 2012 Rachel Carson Environment Book Award for Listed: Dispatches from America’s Endangered Species Act, Roman has written for the New York Times, Science, Audubon, New Scientist, Slate, and other publications. Like many of the animals he studies, Roman is a free-range biologist. He has worked at Harvard University, Duke University Marine Lab, University of Iceland, University of Havana, the U.S. Environmental Protection Agency, and the University of Vermont, where he is a fellow and writer in residence at the Gund Institute for Environment.