Peterson said some of it can actually be traced to before the dawn of mankind, where certain members of groups were designated "high status primates." "The people at the top of the dominant hierarchies kind of stand for the whole hierarchy. So when the hierarchy loses its head, the entire structure is threatened," he said. "We saw that with Kennedy's death because people just fell apart. They were acting like their whole tribe was destroyed. ...It's as old as humanity. You can see going back in history — the death of a king was always a major event."