Form from form: The case for exaptation in rhetorical genre evolution

Since its beginnings in the 1970s, modern rhetorical genre studies has used classical Darwinian adaptation as a key analogy, if not a model, in the study of genre evolution. While the adaptation analogy has obvious strengths, it also produces blind spots. As the studies of rapidly evolving social media genres presented in this article suggest, not all of a genre’s formal features are the result of a purposeful adaptation to an existing rhetorical exigence. Some features repeat and intensify because they are part of the genre’s aesthetic landscape, becoming available to be coopted for a rhetorical purpose later on. This suggests that along with adaptation, exaptation should also be considered as a crucial force in genre evolution. Moreover, the inclusion of exaptation in our model of genre evolution also means that rhetorical genre scholars will need to rediscover the language of aesthetics and form even as genre continues to be studied as social action.