How did feathers evolve and why are they so fascinating and valuable to humans?

Hour 2: How did feathers evolve and why are they so fascinating and valuable to humans? We’ll talk this hour with conservation biologist Thor Hanson, author of “Feathers: The Evolution of a Natural Miracle” (Basic Books, 2011). http://podcastdownload.npr.org/anon.npr-podcasts/podcast/77/510036/137350808/KERA_137350808.mp3[Download MP3]