Human Evolution
Whether or not recursion holds the key to the human mind, the question remains how we came to be the way we are—at once so dominant over the other apes in terms of behavior and yet so similar in genetic terms. In chapter 10, I set the problem in terms of the classic debate between Cartesian discontinuity and Darwinian continuity, and then consider some of the steps that made us the way we are. In modern-day science, it is difficult to avoid the conclusion that the human mind evolved through natural selection, although as we have seen, some recent authors, including Chomsky, still appeal to events that smack of the miraculous—a mutation, perhaps, that suddenly created the capacity for grammatical language. This is the “big bang” theory of language evolution, referred to in chapter 4. But of course we do have to deal with the seemingly vast psychological distance between ourselves and our closest relatives, the chimpanzees and bonobos.
In chapter 11 I consider the possible steps by which we became human. The most critical period was probably the Pleistocene, dating from some 2.6 million years ago until around 12,000 years ago. Evolutionary psychologists have supposed that this was the epoch during which the human mind took shape, largely as a consequence of the shift from an arboreal existence to a more terrestrial existence as hunter-gatherers. But as I explain, we were lucky to make it through, since of the 20 or so hominin species so far identified through fossil remains, only one remains.
That species is Homo sapiens, who emerged in Africa late in the Pleistocene, some time within the past 200,000 years. That species seems to have been endowed with sufficient qualities to ensure survival, and this is the topic of chapter 12. Some have argued that it was language that made all the difference, as though we talked the Neandertals out of existence, but this view is not in keeping with the Darwinian assumptions of this book. In chapter 12 I suggest that it was not language itself that made the difference. Now read on.