Writer David Quammen's working life bounces back and forth between topics such as grizzly bear conservation in the Greater Yellowstone Ecosystem, close to home, and the study of lethal viruses that emerge from bats and chimpanzees and rodents in places like the Congo. Quammen will present on Yellowstone National Park, the first national park in the world, at this year's Shift Festival in Jackson Wyoming. He joins us on Access Utah today.