We report on a case study of the re-situation of scientific knowledge from an originating project to a challenge project to a response project spanning three years in an exchange of views in the published literature of human population genomics ancestry studies. The case study begins with the well-known paper by Rosenberg et al. (2002): “Genetic structure of human populations.” We show that this exchange or “skirmish” is a fruitful unit of analysis expanding and enriching the growing literature on how (and how well) scientific knowledge travels from local to local contexts. We develop an analysis of science in practice in terms of the local workflows implemented to produce knowledge and the challenges created by the re-situation of models, datasets, software, and findings into contexts challenging the value and role of these “objects of knowledge.”