Two hundred years we knew nothing about the past history of humankind. Each culture had its own version of some myth of creation. But in all of them, human beings were the end-all and be-all of all creation. We were at the top of the tree of life. We were sui generis and proud of our uniqueness. But things changed.
Chapter 14 of Yuval Harari’s recent book Sapiens is called “The Discovery of Ignorance.” Sapiens is a lively, enchanting and sometimes provocative example of Deep History, the history of our biological origins. He states that we must be willing to admit ignorance before we can decipher our past.
Western scholars experienced a cultural and intellectual shock with the appearance of that odd Neanderthal skeleton. That was only a century and a half ago. That was the first moment that we acknowledged that the tree actually might have had a lower branch. We began to see that we were ignorant about our biological past.
We had realized that we were totally ignorant about plants and animals when we encountered a tomato, a potato, a llama in the New World. We were thus intellectually prepared to acknowledge our ignorance about the Old World and the role of mankind in creation.
But what evidence did we have? A skeleton here, a piece of a jaw? Only for the last fifty years did we really know where to look. The oldest part of the Old World is a giant rift in East Africa, the Olduvai Gorge which yielded our first trove of ancestor species. Surely Lucy, the australopithecine, is now known us all: close to 2 million years old. Now we are looking further south, deep in caves in South Africa.
The old predilection of looking for a tree-of-live, however, remained obvious. We were looking for branches in a robust single line of descent. Now that we can point to more and more early species, tree is no longer such a convenient metaphor. Fragments, a femur here, a hip bone there, a rare skull or tooth—it was all adding up to a wide and diverse field. Where was the line of ancestors?
There is no longer the sense that some inevitable lineage inexorably led to Homo sapiens sapiens. Homo naledi is another piece of the puzzle of evolution of us. And this time, astonishingly and wonderfully, there are 15 entire individuals, over a thousand bones recovered and more to go. The evidence that all kinds of variations appeared in the ancestry of man is now overwhelming. Small hominids, tall ones, robust ones, fragile ones, flat hands or curved ones, running specialists and climbing specialists.
So which little twig on this complicated bush is the only twig that made it to the present? Of all of the variations that developed over hundreds of thousands of years and the many versions of the hominid family, that group which experienced the mutation that allowed for the development of language prevailed. Speech is linked to a genetic change. The advantage that language provided is the advantage of culture. Homo sapiens sapiens could have been many things, but it finally is the ape that speaks.