Reading Ferdinand de Saussure s Course in General Linguistics one is struck by the extent to which his synchronic theory of language reflects a view of linguistic evolution as analogous to biological evolution. That seems particularly interesting for two reasons. First, linguists and biologists have enjoyed continuing empirical success, since the late twentieth century, in exploiting this analogy. Second, Saussure is usually identified with a view of language as something essentially arbitrary and conventional something distinctively human. By that account linguistic systems would seem to...