When you are walking around in the forest, the park, or even the city, do you ever listen to the songs of birds? Really tune in, and listen? What are they telling each other? Scientist Erich Jarvis says bird whistles can teach us a lot about the ability to learn language. He studies how the brain controls spoken language. He joins us for this bonus episode with a discussion on animals that can learn language, animals that can’t, and much more.