What is behind the term ‘model’ organisms?

Model organisms play a central role in biological research, yet the conceptual questions they raise continue to provoke debate among philosophers. This article examines one such question: What are the distinctive features that qualify model organisms as scientific models? Building on and extending previous work, we propose a refined conceptual framework for understanding model organisms in the context of contemporary scientific practice. Our framework highlights six key features that, collectively, uniquely characterize model organisms. We argue that model organisms should not be viewed merely as components within experimental systems but rather as autonomous experimental systems in their own right.