 Experimental methodology has traditionally been mainly concerned with inferring causal dependencies. However, recent research suggests that we need to broaden its scope. A considerable body of scholarship documents that much biological research is best described in terms of the search for mechanisms, which may be understood as collections of entities and activities that produce a phenomenon that biologists want to understand (e.g., Wimsatt 1974, Machamer, Darden and Craver 2000, Glennan 2005, Bechtel 2006, Craver 2007a). Mechanisms are both what biological science is aiming at and a means to this end, for sketches or schemes of mechanisms can guide scientists in the discovery of missing parts (Darden and Craver 2002, Scholl and Nickelsen 2015).