Just two hours from London, in a stone quarry, archaeologists found one of the biggest ice-age discoveries in recent years. A mammoth graveyard from 200,000 years ago. They also found tools likely used by Neanderthals. The findings are the focus of a new BBC documentary, “Attenborough and the Mammoth Graveyard,” which premieres on Thursday. Lisa Westcott Wilkins is an archaeologist with DigVentures, the team that led the excavation. She joins The World’s host Marco Werman to discuss.