Do sharks sleep, can endangered species be saved, is Sharknado the best shark movie of all time? Marine Conservation Biologist and Shark Researcher Dr. David Shiffman answers your questions in this episode. We talk sharks, saving the oceans and the importance of fish pee. Then, we countdown the Top 5 Kinds of Shirt.Contact the ShowT-ShirtsInstagram Dr. David Shiffman Twitter Dr. David Shiffman Instagram    Learn more about your ad choices. Visit megaphone.fm/adchoices