Evolutionary linguistics is a delicious blend of scientific disciplines and methods. It’s an attempt to answer the question of why humans, alone of all the animals on our planet, have this wild and wonderful communication system. Language is a truly mind-bogglingly complex and efficient phenomenon, allowing us to combine sounds into words and words into sentences that can communicate an infinite range of ideas. How did this phenomenon get here?
Language leaves no fossils, and written language has only been around for a tiny portion of our species’ history. So, evolutionary linguists draw on data from many different sources. We can infer things from the fossil record about the behaviour of ancient humans, and what physical speech apparatus they might have had. We can look at historical evidence of how languages have changed over time, and extrapolate those findings to a longer timescale. Other animals are a great source of evidence: we can study species with communicative systems that share some of the features of language, and try to work out what humans have in common with those animals in terms of social behaviour and ecology.
Some of the best clues come from present-day language: there are clues in how children learn language, and also in how new languages, like Nicaraguan Sign Language, behave as they emerge. If we look across all the languages in the world around us today, that snapshot can give insights into what features are rare or common, and how language works as a system.
And sometimes, artificial contexts are the best way to probe questions about how language evolved. Lab studies that get people to learn and use novel communication systems can teach us what happens to those systems when they pass through human minds. Computer simulations allow us to see what happens to communication systems as they’re passed through multiple generations of learners, and what kinds of learners do best with different kinds of communication systems.
Evolutionary linguistics makes up only a small part of the science I cover, but it’s given me a neat window into a huge array of disciplines and different ways of gathering evidence. And I still think it’s one of the most intriguing and exciting questions we can ask about our species.