Research on areal typology reflects the effects of structural convergence as it is induced by situations of contact between speakers of different languages with various genetic affiliations. Long periods of contact across languages spoken within a larger geographic space often result in areal clusterings of grammatical properties which are discussed in terms of linguistic areas since Trubetzkoy (1930) introduced this notion under the German term of Sprachbund. Linguistic areas are characterized by structural similarities across a set of geographically adjacent…