This week we're joined by Joel Berger, a professor at Colorado State University and a senior scientist with the New York-based Wildlife Conservation Society, who recently wrote a commentary for Mongabay arguing that there are too many large mammals like yaks and Saiga antelope living in remote regions (so-called "edge species") that are wrongfully overlooked by conservation initiatives. Then from Peru, Dr. Andrew Whitworth, a conservation and biodiversity scientist with the University of Glasgow, shares rare recordings he recently made in the field of a critically endangered bird called the Sira Curassow.