![Drilling 139 meters down to volcanic rock provided scientists with a million-year environmental record.](https://cdn.mos.cms.futurecdn.net/5Pr7EdXCAuRPXAnzoQvNt3-320-80.jpeg)
Turbulent environment set the stage for leaps in human evolution 320,000 years ago
People thrive all across the globe, at every temperature, altitude and landscape. How did human beings become so successful at adapting to whatever environment we wind up in?