 The last decade has seen two kinds of innovations related to studying changes in particular languages. One, which we will call ‘linguistic phylogeny’, concerns the application of stochastic phylogenetic methods to investigate prehistoric population and language dispersion (Gray and Jordan 2000, Gray 2005, Atkinson and Gray 2006, Gray et al. 2009). These methods answer questions about how members of a family of languages are related to each other and dispersed throughout a geographic area. The second, which we will call the effects of transmission, examines how interpreted artificial languages (sets of signifier/signified pairs) change under a range of transmission conditions (Kirby et al. 2008, Kirby 2001, Hurford 2000), thus providing evidence about how the process of transmission affects the characteristics, especially the structure, of the transmitted interpreted system.