Hungry for Knowledge: Oliver Smithies is a toolmaker. He shared the Nobel prize for discoveries that led to the development of knockout mice. Diego Bohorquez uses mouse models to understand how our gut regulates appetite. He has wanted to meet Smithies ever since he moved from his native Ecuador to Duke University in the United States. When the two meet in Lindau they have an instant rapport and soon they're sharing ideas about their research projects and talking about what makes a successful scientific collaboration.