Preparing for survival mode on a hike across the Silk Road

Three years ago, Pulitzer-winning journalist Paul Salopek embarked on a decade-long walk around the world, charting the path of the original human emigrants who left their birthplace in eastern Africa to spread across the globe. As he prepares to follow the Silk Road from Central Asia into China, Salopek checks in with Hari Sreenivasan to reflect on his journey thus far and what lies ahead.