Humans are a force radically reshaping the Earth’s surface – but what forces are shaping homo sapiens? Today on the show, we feature two stories. First we look at ongoing human evolution and genetic mutations (btw, we are still evolving). Our second piece is about a human and animal instinct that we rarely think about – the impulse to play. More on Stuart Brown and the National Institute for Play: http://www.nifplay.org/ Creative commons music by Johnny_Ripper, Podington Bear, and Myriadar