You have a lot to thank sheep for. Yes, sheep. More than just wool and meat — sheep have played a part in the development of contraception and reproduction in humans. It's not as dodgy as it sounds, but it is absolutely surprising. Listening to this show will have you thanking every sheep you see from here on out. Featuring: Tara Farms, YouTuber, and sheep farmer. Sally Coulthard, historian, smallholder, and author of A Short History of the World according to Sheep. Dr Charles Roselli, Oregon Health and Science University, Portland. Professor Emeritus Gareth Evans, University of Sydney. Dr Stephan Leu, The University of Adelaide. Production: Ann Jones, Presenter/Producer. Petria Ladgrove, Producer. Additional mastering: Nathan Turnbull. This episode of What the Duck?! was produced on the land of the Wadawarrung and Kaurna people.