Figure 1.

The link between genes and the universal properties of language is mediated by development and cultural transmission. The extent to which these two processes have non-trivial dynamics is an important consideration when proposing evolutionary accounts of language. Fitness does not depend directly on the genes underpinning the language faculty, but rather the linguistic phenotype (i.e., languages). This opens up the possibility for development and cultural transmission to shield genetic variation from the view of natural selection (Figure adapted from Kirby et al., 2007). © 2007 by The National Academy of Sciences of the USA.