Are organisms models? Are models experiments? Some thoughts

Philosophy of modelling usually distinguishes three modelling media: equations, algorithms, and materials. The third category includes things such as metal rods, wooden blocks, and lego (for example). But it also includes model organisms and experimental systems that are made of organisms and parts of organisms. These materials might give us pause for thought. How can a complex organism ‘model’ biological phenomena, when the organism is that very phenomenon? And surely everyone expects experimental systems to be empirical tests for hypotheses, and not a surrogate or representation of any sort, don’t they? I will discuss these and other objections, with special attention to how organismal and experimental model systems can interact with mathematical models. These interactions give indications of the special modelling properties organisms and experiments are meant to have. These properties might mean we need to supplement our views of what models are.