One good way to learn about the human spark is to investigate a closely related species that lacked it. Alan Alda traveled to a French cave called Roc de Marsal, where Neanderthals sheltered intermittently for tens of thousands of years. The archaeologists who excavate here are becoming experts on Neanderthal life. In this video, Alan quizzes them on what they believe the big differences were between Neanderthals and early modern humans. Harold Dibble, Shannon McPherron, and Dennis Sandgathe explain what they think differentiates Neanderthals from us… and why the human spark might actually have been more of a human smolder.