Language is driven by culture, not biology

Language in humans has evolved culturally rather than genetically, according to a study by Professor Nick Chater (UCL Cognitive, Perceptual and Brain Sciences) and US colleagues published today in the 'Proceedings of the National Academy of Sciences' (PNAS). By modelling the ways in which genes for language might have evolved alongside language itself, the study showed that genetic adaptation to language would be highly unlikely, as cultural conventions change much more rapidly than genes. Thus, the biological machinery upon which human language is built appears to predate the emergence of language. According to a phenomenon known as the Baldwin effect, characteristics that are learned or developed over a lifespan may become gradually encoded in the genome over many generations, because organisms with a stronger predisposition to acquire a trait have a selective advantage. Over generations, the amount of environmental exposure required to develop the trait decreases, and eventually no environmental exposure may be needed - the trait is genetically encoded. Professor Nick Chater, UCL Cognitive, Perceptual and Brain Sciences, said: 'Language is uniquely human. But does this uniqueness stem from biology or culture? This question is central to our understanding of what it is to be human, and has fundamental implications for the relationship between genes and culture.