Derek Denis (faculty), Matt Hunt Gardner (Ph.D. 2017, now at St. Mary's University), Marisa Brook (faculty), and Sali A. Tagliamonte (faculty) have a new paper out in Language Variation and Change, 31(1): "Peaks and arrowheads of vernacular reorganization."
A key component of Labov's (2001:411) socially motivated projection model of language change is the hypothesis that adolescents and preadolescents undergo a process of vernacular reorganization, which leads to a "seamless" progression of changes in progress. Between the ages of approximately five and 17, children and adolescents increase the "frequency, extent, scope, or specificity" of changes in progress along the community trajectory (Labov 2007:346). Evidence of advancement via vernacular reorganization during this life stage has come from peaks in the apparent-time trajectory of a change around the age of 17 (e.g., Labov 2001, Tagliamonte and D'Arcy 2009). However, such peaks do not rule out the alternative explanations of retrograde change or age-grading. This paper presents both apparent time and real-time evidence for vernacular reorganization. We observe the arrowhead formation – a counterpart of the adolescent peak – for quotative be like in a trend study of adolescents and young adults in Toronto, Canada. Our results rule out the alternative explanations for previously observed adolescent peaks.