Humans are the only species known to use fully symbolic language: a system capable of expressing abstract ideas, imaginary worlds and endless combinations of meaning. But how did we get there?

The origins of language have fascinated philosophers, scientists and storytellers for thousands of years. Despite all our advances in linguistics, archaeology and cognitive science, we still don't know exactly how language began.

That uncertainty hasn't stopped people from trying to solve the mystery. In fact, some of the earliest theories of language's origins are among the strangest and most entertaining ideas in the history of science.