Humans: The 70,000 Year History

A photographer taking pictures of the Neanderthal man ancestor's reconstruction, displayed in a show of the Prehistoric Museum in Halle, eastern Germany.

Yuval Noah Harari discusses his new book, Sapiens: A Brief History of Humankind, which explores the ways in which biology and history have defined us and enhanced our understanding of what it means to be human. One hundred thousand years ago, at least six different species of humans inhabited Earth. Yet today there is only one—homo sapiens. What happened to the others? And what may happen to us?