How Language Began: The Story of Humanity's Greatest Invention

by Daniel L. Everett

The manufacture of tools requires planning, imagination (having an image of what the final tools should look like) and, at least eventually, communication of some sort for instructing others in how to make tools. The sequential operations call upon the prefrontal cortex and produce cultural selectional pressure for more cortical horsepower, more smarts. However, this pressure might have worked, the larger prefrontal cortex of earlier Homo toolmakers, relative to australopithecines, may be a response to it. Not surprisingly, therefore, about 1.76 million years ago, roughly 300,000 years after the rise of Homo erectus, Olduwan tools were joined by other erectus-manufactured tools, in particular a new type called the Acheulean (Figure 14). Many people suggest that this long, mysterious period without innovation, longer by far than (yet still reminiscent of) the Dark Ages of Europe, is due to ‘low fidelity social transmission’. In other words, because erectus lacked language. But this is not a necessary inference. Cultural conservatism is a powerful and common force. It is always easier to imitate than to innovate, especially if a culture discourages innovation, as is still common throughout the world.