In his new study, Burridge presents a deliberately minimal model of language change, which focuses on explaining dialect distribution solely in terms of topographical features and speaker interaction. The model assumes the existence of multiple linguistic variants for multiple linguistic variables, which effectively define different dialects. In determining whether a given speaker adopts a specific variant, the model does not consider “social value” factors. Instead, it assumes that speakers interact predominantly with people living in their local environment (defined by some radius around their home), and that they will conform to the speech patterns of the majority of people in that geographic vicinity. Such local linguistic alignment favors the emergence of distinct dialect areas, with dialect boundaries tending to shorten in length in a way that mimics how surface tension minimizes the surface area of a water droplet (see Fig. 1). In a region with uniform population density, this language-based surface tension will cause the boundary between two dialects to form straight lines. Densely populated areas, however, interfere with boundary straightening by repelling boundaries and effectively creating new dialect areas around themselves. Furthermore, topography can have an imprint on dialect spatial distributions. In systems with irregular perimeters, Burridge shows that boundary lines tend to migrate to places where they emerge perpendicular from the edge of the system, such as indentations in coastlines.Original research HERE (PDF).