What is Meat? Changing the Answer Might Change the Planet.

Industrial agriculture and livestock are big contributors to greenhouse gasses. Making one hamburger requires hundreds of gallons of water. As more studies highlight the environmental impact of meat, some scientists and entrepreneurs are rethinking meat as we know it. For today's Please Explain, we'll talk to a few of them.  Professor Mark Post is a faculty member at Maastricht University, and a leader in making Cultured Beef. He is working on a process that makes a beef hamburger using stem cells. Ethan Brown is the CEO of Beyond Meat. The company makes plant-based meat substitutes that replicate beef and chicken, attempting to make plant proteins behave nearly identically replicate meat proteins. Ethan Brown, CEO of Beyond Meat (Courtesy of MBooth) A burger made from Cultured Beef, which has been developed by Professor Mark Post of Maastricht University in the Netherlands. (David Parry/PA)