ABSTRACT
In Chapter 1 I pointed out the crucial importance of our peculiar vocal tract in allowing us to speak. But, along with that vocal tract, our ancestors also evolved something else that appears to be essential for using language: our large brain. For millions of years, even after they had learned to walk upright, our ancestors made do with small ape-like brains-then suddenly, almost overnight in evolutionary terms, our brains quadrupled in size. No one knows just why this happened, but there is no shortage of speculationsand the favourite speculation is that our brains were developing specifically to allow us to use language.
