What the Origins of Humanity Can and Can’t Tell Us

Since the Neanderthal discovery, the start date for human prehistory has been pushed farther and farther back. The bones of Java Man, found in the eighteen-nineties, and of Peking Man, found in the nineteen-twenties, suggested that humans emerged out of Asia between seven hundred thousand and 1.5 million years ago. Twentieth-century excavations of the genus Australopithecus in South Africa, Tanzania, and Ethiopia—where forty per cent of an australopithecine skeleton dubbed Lucy was retrieved, in 1974—shifted hominin origins to some 3.2 million years ago and informed the “out of Africa” theory that remains widespread today.