Recent work on epistemic integration in the life sciences has emphasized the importance of integration in thinking about explanatory practice in science, particularly for articulating a robust alternative to reductionism and anti-reductionism. This paper analyzes the role of models in balancing the relative contributions of lower- and higher-level epistemic resources involved in this process. Integration between multiple disciplines proceeds by constructing a problem agenda (Love 2008), a set of interrelated problems that structures the problem space of a complex phenomenon that (...) is investigated by many disciplines. The usage of models, it is argued, mark changes in a phenomenon’s problem agenda depending on the task that is expected of it. Particularly, it emphasizes the sensitivity of a problem agenda to changing attitudes in the solutions to the conceptual and empirical items constituting that agenda. The analysis will proceed by means of a case study, the Reichardt motion detector, a model that has been vital to the methodological and conceptual development of research on motion detection, especially in invertebrates. As will be seen, the history of the Reichardt model will exemplify the dynamic changes that occur in the interdisciplinary negotiations that comprise the active efforts of various sciences working to integrate their resources. (shrink)